Patient and aneurysm characteristics
\r\n\tThe discussion will include between others topics: biodegradation processes of by-products coming from food-processing industries, tertiary treatment of wastewaters with microalgae coupled with the generation of potentially commercial interest compounds, biotechnological processes to improve lignocellulosic waste treatment or potential use of fungi in the degradation of environmental pollutants.
\r\n\tThis book intends to provide the reader with a comprehensive overview of the current state-of-the-art in biodegradation processes that contribute to a sustainable and circular bioeconomy giving added value compounds from waste and by-products, up to now hidden, and reducing waste generation at the same time.
Endovascular treatment of intracranial aneurysm has been increasingly performed worldwide. The recent publication of a multiple center randomized trial showing improved safety and clinical outcome of patients treated with endovascular methods as compared with open clipping is encouraging to endovascular neurosurgeons and accelerates this trend. [1] Stent-assisted coil embolization, which is earliest reported by Higashida in 1997 [2] and now widely accepted, has expanded the treatment possibilities. It allows for adequate coil placement, prevents coil protrusion into the parent vessel, and also helps prevent aneurysm recanalization. In the last decade, the development of intracranial stents has increased the options for the treatment of wide-necked aneurysms. Successful experiences of the stent-assisted coiling have been reported by many teams in endovascular neurosurgery centers throughout the world. However, most of the reported complications involved a limited number of patients and varied among reports.[3,4] There has been no systematic report of a relatively larger number of patients treated at a single institution, to provide an overview of these complications. The purposes of this article are to systematically document and analyze the periprocedural and follow-up complications of stent-assisted coiling of cerebral aneurysms at our institution and to tentatively answer the following question: is the incidence of complications with stent-assisted coiling acceptable, compared with the benefits?
Between Jul 2003 and Dec 2009, 232 consecutive patients with 239 wide-neck aneurysms underwent stent-assisted coil embolization at our institution. Therapeutic alternatives were discussed between neurosurgical and neurointerventional teams. Informed consent from the patients and institutional review board approval was obtained. The medical records, radiographic studies and endovascular procedure reports were reviewed. Patient and aneurysm characteristics are summarized in table 1.
No. of patients | 232 |
Age (y) | |
Mean | 55.1 |
Range | 18-81 |
Gender | |
Female | 142 |
Male | 90 |
Ruptured aneurysms (%) | 129 (54.0) |
Hunt and Hess grade | |
I | 39 |
II | 46 |
III | 34 |
IV | 7 |
V | 3 |
Unruptured aneurysms (%) | 110 (46.0) |
Headache | 35 |
Previous SAH | 29 |
Incidental | 22 |
CN paisy | 13 |
TIA | 11 |
Aneurysm location (%) | |
Anterior Circulation | 195 (81.6) |
PcomA | 49 |
AcomA | 12 |
Paraclinoid ICA | 41 |
Cavernous ICA | 20 |
Ophthalmic | 37 |
ICA bifurcation | 14 |
AchoA | 17 |
A1 segment of ACA | 5 |
Posterior Circulation | 44 (18.4) |
BA | 18 |
VA | 12 |
VB junction | 9 |
PICA | 5 |
Aneurysm size (%) | |
Small | 164(68.6) |
Large | 43(18.0) |
Giant | 32(13.4) |
Neck size (mm) | |
Mean | 5.9 |
Range | 2-24 |
Patient and aneurysm characteristics
All procedures were performed under general anesthesia. Patients having unruptured aneurysms were premedicated with antiplatelet therapy consisting of aspirin 300 mg and clopidogrel 75 mg for 3 days before the procedure. Patients with SAH were loaded with aspirin 300 mg and clopidogrel 225 mg via nasogastric tube after general anesthesia. All patients received systemic heparinization to raise the activated clotting time (ACT) at about 300 seconds and continuous intravenous infusion of Nimodipine, 2mg/hour to prevent vasospasm during the procedure. In patients with ruptured aneurysms, heparinization started before puncture, and in patients who presented with acute SAH, heparinization started after aneurysm catheterization. A full three- or four-vessel cerebral angiogram was performed to permit a complete evaluation of the aneurysm, measure the aneurysm neck, width, and height, and measure the parent artery proximal and distal to the aneurysm. A 6F or 8F sheath was introduced in the right femoral artery following a standard Seldinger puncture. A 6F or 8F Envoy guiding catheter (Johnson & Johnson) was then guided into either the cervical internal carotid or vertebral artery, depending on the location of the aneurysm. The microcatheters were Prowler series (Johnson & Johnson), Excelsior SL-10, or Excelsior 1018 (Boston Scientific/Target Therapeutics). In all cases, embolization was completed by packing the aneurysm sac with a variety of commercially available coils. After the procedure, the patient was moved to the neurosurgery intensive care unit for monitoring and received low-molecular weight heparin calcium 4000IU/12h for the next 48 hours. Clopidogrel 75 mg each day was orally taken for an additional 30 days, and aspirin 100 mg for 6 months.
Stent deployment was successful in 237 of 239 aneurysms, and failed in two aneurysms. Strategies used regarding the sequence of stenting and coiling in 237 treated aneurysms were the following:
Stents were delivered before coiling in 205 of 237 aneurysms (86.5%).
Stenting before coiling in the same session in 191 aneurysms (80.6%). In 67 of 191 aneurysms, the sequential technique was used, by which the microcatheter was introduced into the sac through the struts of the stent. In 93 of 191 aneurysms, the jailing technique was used, by which the coiling catheter was “jailed” between the vessel wall and the stent. Other 31 of 191 aneurysms were treated using the semi-deployment technique. It consisted of the delivery microcatheter into the aneurysm sac and navigating a self-expandable stent into the parent vessel, and subsequently partially deploying (approximate 50%-60% of its opening) the stent, which covered the distal part of the aneurysm to narrow the neck and leaves room to modify the coil delivery microcatheter position during embolization. After a homogeneous coil framing or complete embolization is achieved, the stent was fully deployed. If necessary, coiling could be continued using traditional jailing technique to obtain circulatory exclusion of the lesion. A illustrated case of the whole semi-deployment technique is shown in Figure 1.
Three dimensional reconstruction (A) of the right ICA in anteroposterior view demonstrated a posterior communicating artery aneurysm. The Neuroform stent delivery system was brought up over the exchange microguidewire to cross the aneurysm neck. The stent was partly deployed to narrow the aneurysm neck after aneurysm catheterization (B). Homogeneous coil framing was achieved without coil prolapse by the limitation of the partially-deployed stent. (C). After several coils were placed, the stent was fully deployed and coiling continued using traditional jailing technique (D). Postprocedure angiogram (E) revealed complete occlusion. 13 months follow-up right common carotd artery angiogram (F) revealed high-grade stenosis within the stented segments of right ICA. Collateralisation was seen over the anterior communicating artery from the left side (G). Superselective angiogram (H) demonstrated that right ICA was not completely occluded. Then, balloon angioplasty of the right ICA was performed (I). Postangioplasty control angiography demonstrated substantial improvement in the caliber, but flow to right cerebral anterior artery was still delayed (J).
Stenting before coiling in a second session in 14 aneurysms (5.9%). The main reason for using this option was the difficulties of accessing the aneurysm for coiling after initial stent placement, especially when the parent artery was tortuous, or the aneurysm was small. The coiling procedure was usually performed from 1 to 2 months after the stenting procedure.
Stents were delivered after coiling in 31 of 237 aneurysms (13.1%).
Stenting after coiling with balloon remodeling technique in 24 aneurysms. The choice of this option was to decrease the risk of thromboembolism complications in some partially thrombosed aneurysms.
Bail-out stenting in 7 aneurysms. In these cases, the deployment of the stent was not planned in advance. Trapping of an extruded coil or coil mass by means of stent placement could prevent parent vessel closure and obviate the need for coil removal.
Stent was delivered alone in one aneurysm (0.4%). A 38-year-old woman with a basilar aneurysm was planned to treat with sequential technique. Because trans-stent aneurysm catheterization was difficult and caused stent movement, coil embolization was postponed to a second session. Fortunately, intraaneurysmal spontaneous thrombosis was noted by angiography 3 months later, and coiling was no more an option for her. Complete occlusion was observed at 1-year follow-up angiography (Figure 2).
Angiography demonstrated a basilar trunk aneurysm in a 38-year-old woman with SAH (A B). A Neuroform stent (4.5 × 20 mm) was deployed across the aneurysm neck, and coil embolization was postponed to a second session due to difficulty in trans-stent aneurysm catheterization (C). One-year follow-up angiography demonstrated complete occlusion (D E).
All patients underwent CT scanning within 6 hours after the procedure. During the hospital stays, physicians performed neurological examinations of the patients once each day. After discharge, clinical follow-up data were collected by clinic visitation, follow-up angiography, or telephone interview. Clinical outcome was graded according to modified Rankin score (mRS), as follows: excellent (mRS 0-1), good (mRS 2), poor (mRS 3-4) and death (mRS 5). For each patient, 6 months, 1 year, 3 year and 5 year follow-up angiogram were recommended. The pre-embolization, post-embolization and follow-up (if possible) angiograms were reviewed and compared by 2 senior endovascular neurosurgeons not involved in the procedure for initial and follow-up occlusion grade, which was classified as class 1: complete occlusion (no contrast filling the aneurysmal sac); class 2: neck remnant (residual contrast filling the aneurysmal neck); class 3: residual flow (residual contrast filling the aneurysmal body). [5] Recanalization was defined as more than 10 % increase in contrast filling of the aneurysm; less than 10 % increased filling was defined as unchanged. [6]
Angiographic results and clinical outcome were evaluated. Cases with complications were analyzed, including radiological findings, clinical presentations, management experience and clinical sequelae.
SPSS 11.0 software (SPSS, Inc, Chicago, IL) was used for statistical analysis. A chi-square test was used to compare the incidences of intraprocedural rupture and thromboembolic complications between ruptured unruptured aneurysms and to compare the incidences of complete occlusion rate between different stenting strategies.
Immediate angiographic results of the 236 aneurysms treated with stent-assited coiling are summarized in Table 2.
class 1 | class 2 | class 3 | ||
Overall | 236 | 162 | 45 | 29 |
Small | 162 | 128 | 21 | 13 |
Large | 41 | 22 | 11 | 8 |
Giant | 33 | 12 | 13 | 8 |
Ruptured | 128 | 82 | 26 | 18 |
Unruptured | 108 | 80 | 19 | 11 |
Overall (%) | 236 | 162(68.6) | 45(19.1) | 29(12.3) |
Immediate angiographic occlusion classification
Aneurysm occlusion rate was analyzed in relation to different stenting techniques, bail-out stenting cases excluded. Stenting before coiling was performed in 205 aneurysms and angiographic results showed class 1 occlusion in 142 (69.3%) aneurysms, class 2 in 39 (19.0%) aneurysms, and class 3 in 24 (11.7%) aneurysms. Stenting after balloon-assisted coiling was performed in 24 aneurysms and angiographic results showed class 1 occlusion in 19 (79.2%) aneurysms, class 2 in 3 (12.5%) aneurysms, and class 3 in 2 (8.3%) aneurysms. On comparative analysis of stenting before coiling versus stenting after balloon-assisted coiling, the complete occlusion rate did not show statistical difference ( P=0.315, Χ[2] test ).
Of the total of 239 procedures for 232 patients, 34 procedural complications occurred, of which 26 were in the anterior circulation and 8 in the posterior circulation. Table 3 summarizes the procedural complications. Procedure-related morbidity and mortality were 4.2% and 1.3%, respectively.
Complication | No sequela | Morbidity | Mortality | Total | Incidence(%) |
Thomboembolism | 8 | 4 | 1 | 13 | 5.4 |
Intraprocedural rupture | 3 | 3 | 2 | 8 | 3.3 |
Coil protrusion | 5 | 0 | 0 | 5 | 2.1 |
New mass effect | 1 | 2 | 0 | 3 | 1.3 |
Vessel injury | 2 | 1 | 0 | 3 | 1.3 |
Stent dislodgement | 2 | 0 | 0 | 2 | 0.8 |
Total | 21 | 10 | 3 | 34 | 14.2 |
Procedure-related complications in aneurysms
Thirteen periprocedual thromboembolic events occurred; 9 were in ruptured aneurysms and 4 in unruptured ones. Nine thromboembolic complications were evident during the procedure, and four were clinically and angiographically noted after the procedure. Complete or partial recanalization was achieved in 9 cases by local or systemic administration of abciximab or urokinase and mechanical disruption of clot with microwire immediately. On last follow-up, eight patients completely recovered, two patients developed residual mild neurological deficit and independent daily activity, and two patients developed hemiplegia and became dependent. A 68-year-old woman with ruptured PcomA aneurysm (Hunt-Hess gradeⅠ) developed right hemiparesis six hours after the procedure. A thrombus in the distal stent segment of right ICA was confirmed by angiography and the left cerebral hemisphere infarction was noted by MRI. She developed severe brain herniation eventually, and decompressive craniotomy failed to save her life.
Intraprocedural aneurysmal rupture occurred in eight aneurysms due to coil extrusion (n=2), microcatheter protrusion (n=5), or inflation of the balloon (n=1): three in the PcomA, two in the ophthalmic artery, one in the AComA, one in the AchoA, and one in the basilar tip. All eight ruptures occurred during embolization of acutely ruptured small aneurysms, four of which occurred when coiling microcatheter accessed the aneurysm through the struts of the stent. All intraprocedural ruptures were managed with a protamine injection for heparin reversal and further coil embolization. External ventricular drainage (EVD) surgery was preformed in four cases with postprocedural Fisher grades of III or IV. Five of these ruptures resulted in adverse outcome (3 neurological sequelae, 2 death).
Coil protrusion occurred in five procedures, in four of which the last several loops of a small coil (diameter 2 mm) in part protruded through the interstice after detachment, and in one of which the coil was unraveled when a second stent-assisted coiling was performed on a 71-year-old female with bilateral PComA aneurysms. During positioning of the third coil (3 mm × 6 cm), the microcatheter was repelled from the aneurysm from the aneurysm into the parent vessel, and it was noted that the trailing end of the coil was unraveled, with several loops in the parent vessel, which affected the blood flow. After attempts to pull back the coil or to replace the coil failed, a balloon catheter was introduced into the guiding catheter, and the trailing end of the coil was caged in the guiding catheter by inflation of the balloon. Then the coil was stretched into the aorta. Fortunately, none of these patients had sequela.
Cranial nerve III palsy occurred in three large PComA aneurysms, which thought to be the result of the compressive effect of a coiled aneurysm. Only one patient recovered under steroid therapy.
Vessel injury occurred in three procedures. Two cases of small vessel dissections developed during balloon manipulations. Each involved the carotid siphon. Both dissections spontaneous healed on angiographic follow-up, with no clinical consequence. One case of intracranial hematoma was noted in a 67-year-old woman with a ruptured right PcomA aneurysm (Hunt-Hess grade II). She developed conscious disturbance about one hour after treatment. Intracranial CT showed 30 ml hematoma in the right ipsilateral fissure, most probably due to MCA injury with the microguidewire used for stent introducement. Surgical evacuation was performed and she discharged with mild hemiparesis.
Stent dislodgement during treatment occurred in two procedures: one caused by aneurysm catheterization through the stent struts and the other caused by retrieving the coiling catheter jailed between the stent and vessel wall. In the former case, the stent still covered the aneurysm neck and embolization was completed successfully. In the latter case, the coil mass partially herniated to the parent artery, which blocked the blood flow, during treatment for a left paraclinoid ICA aneurysm. Fortunately, we did not pull back the exchange microwire over which the stent delivery system was brought up. Another Neuroform stent (4.5 × 30 mm) was advanced through that exchange microwire and successfully deployed across the aneurysm neck. The herniated coil mass was pushed back against the vessel wall, and complete flow recanalization was achieved, with no clinical consequence (Figure 3).
Angiography showed a left paraclinoid ICA aneurysm in a 62-year-female (A). Retrieving the coiling catheter jailed between the stent and vessel wall caused Enterprise stent dislodgement and the coil mass partially herniated to the parent artery, which blocked the blood flow (B). A Neuroform stent (4.5 × 30 mm) was advanced through the exchange microwire and successfully deployed across the aneurysm neck to push back the coil mass against the vessel wall (C). Frontal and lateral angiogram (D E) showed complete flow recanalization of the parent artery and class2 occlusion of the aneurysm.
Though all 129 patients with SAH were managed with systemic administration of Nimodipine and/or lumbar drainage of cerebrospinal fluid, twenty-four (18.6%) had systematic vasospasm, resulting in five cases of parent artery occlusion during the procedure. one aneurysm was located at AComA, Two at PcomA, and two at basilar tip. They were managed with local administration of Nimodipine 3mg and narceine 30mg immediately. Three patients resolved well after administration and had no deficit. In a 58-year-old woman with ruptured basilar tip aneurysm (Hunt-Hess grade Ⅲ), after a successful stent deployment vasospasm was noted in the basilar trunk. After immediate management, angiogram showed vasospasm completely resolved. However, she did not recover from the transient ischemia. Fellow-up MR showed infarct in the pons. Eventually, she discharged to a skilled nursing facility, not cognitively able to participate in her care. In a 70-year-old man with ruptured left paraclinoid ICA aneurysm (Hunt-Hess grade Ⅲ), vasospasm was noted in the left supraclinoid ICA during post-procedure angiography. After immediate management, angiogram showed vasospasm completely resolved. However, decreased level of consciousness occurred 24 hours later after the treatment. CT scan showed left cerebral hemisphere infarction. Cerebral angiography revealed diffuse severe bilateral anterior and posterior circulation vasospasm. An emergent decompressive craniotomy was performed. This patient had a long recovery with right hemiplegia and expressive aphasia, and then discharged to a skilled nursing facility.
Of the 129 patients with SAH, nine (6.9%) had shunt-dependent hydrocephalus. All these nine patents received EVD only. One poor-grade patient died of the initial effect of SAH, and other patients recovered gradually. no patients developed chronic hydrocephalus at clinical follow-up.
Three patients died of procedure-related complications, and eight patients with acute SAH (high Hunt-Hess grade) died because of the severity of their initial hemorrhage during hospitalization. All other 221 patients were clinically evaluated. Clinical follow-up was obtained from < 1 month to 81 months with a mean of 57.7 months. The mRS score was excellent in 167 patients, good in 38 patients, and poor in 11 patients at last follow-up. Five died of other diseases. No rehemorrhage of treated aneurysm occurred.
Follow-up angiography was obtained using DSA or MRA in 155 patients with 159 treated aneurysms. Angiographic follow-up was obtained from 3 to 62 months, with a mean of 39.2 months. 131 of the 155 patients (84.5 %) had >1 year follow-up. The main reasons that patients were lost to follow-up were the patients’ refusal to return, economical problem and travel distance. In these 159 angiographic followed aneurysms, the follow-up angiograms of 23 aneurysms (14.5 % of the follow-up angiograms) demonstrated recanalization (Table 4). Of note, 8/22 (36.4 %) class 2 and class 3 aneurysms converted to class 1 on last follow-up. Seventeen of these aneurysms underwent successful re-embolization. The other six patients’ angiogram showed an increasing remnant neck on the first follow-up examination, but the subsequent follow-up angiogram showed a stable appearance. Therefore, re-embolization was not a treatment option for them. No symptomatic procedural complications were seen in the retreatment.
Aneurysm size | Recanalized |
Small | 9/102 |
Large | 6/31 |
Giant | 8/26 |
Overall | 23/159(14.5) |
Immediate aneurysm result | Recanalized (%) |
Class 1 | 9 /108 |
Class 2 | 9/32 |
Class 3 | 5 /19 |
Overall | 23/159 (14.5) |
Recanalization rates
In-stent stenosis was confirmed in two patients by follow-up angiography. In a 45-year-old man, after stent-assisted coiling of a VB aneurysm, delayed in-stent stenosis was seen at 3-month follow-up but had resolved spontaneously at 12-month follow-up. Fortunately, he patient had no symptom. In a 65-year-old man, a 4.5 mm ×15 mm Neuroform stent was deployed in the paraclinoid and communicating segments of right ICA to treat a PcomA aneurysm. High-grade stenosis within the stented segments of right ICA was present 13 months after the procedure. He suffered from a mild left hemiparesis. In view of the severity of the stenosis and symptoms while on aspirin, balloon angioplasty of the right ICA was performed. Postangioplasty control angiography demonstrated substantial improvement in the caliber and the patient recovered fully (Figure 1).
One patient developed ophthalmic artery occlusion 6 months after the procedure in whom the ophthalmic artery origin was bridged with the stent. Fortunately no clinical problem occurred because of the reconstruction of the ophthalmic artery via external carotid artery collaterals.
A case of Déjérine syndrome occurred in a 52-year-old woman with a VB junction aneurysm treated by stent-assisted coiling eight month after the procedure. She suffered from vertigo, bilateral deep sensory disturbance and right mild hemiparasis. Diffusion-weighted MRI demonstrated increased signal in the medial medulla. The mechanism was suggested that unusually aggressive neointimal response to the stent resulted in occlusion of a small penetrating artery from the stented segment of the vertebral artery, though direct evidence was not found by angiography. (Figure 4)
Frontal and lateral angiogram (A B) showed VB junction aneurysm in a 52-year-old woman. Complete occlusion was achieved by stent-assisted coiling (Neuroform 4.5mm ×30mm) (C). Diffusion-weighted MRI demonstrated increased signal in the medial medulla eight month after the procedure (D). Fowllow-up angiogram demonstrated that the stented segment of the parent artery appeared intact, with no evidence of dissection or in-stent stenosis (E F).
No rehemorrhage of treated aneurysm occurred. One 73-year-old male died of contralateral putaminal hemorrhage 7 months after discharge. Though he had a history of hypertension for nearly 20 years, posttreatment antiplatelet might be a precipitating factor.
All 8 intraprocedual ruptures, and 9 of 13 thromboembolic events were in the SAH group. The incidence of intraprocedural rupture and thromboembolism were 6.2% and 6.9%, respectively, in the ruptured group and 0% and 3.6%, respectively, in the unruptured group. There was a statistically significant difference in the incidence of intraprocedural rupture between two groups (P =0.008). The incidence comparison for thromboembolism between these groups, however, gave a P value of 0.256.
Endovascular and surgical treatment of wide-neck and fusiform intracranial aneurysms has remained technically challenging. Stent-assisted aneurysm embolization is a new tool in the treatment of intracranial aneurysms and maybe particularly useful in the case of wide-necked or dissecting aneurysm. The earliest clinical report of stent-assisted coiling of an intracranial ruptured cerebral aneurysm is by Higashida et al, in 1997[2]. From then on, with improvements in microstent technology, more reports from various centers describing the experimental and clinical use of different stents for embolization assistance has reported good results in the literature.[7-13] Up till now, several literatures have demonstrated the technical feasibility, efficacy of treating complicated intracranial aneurysms. [14-17] The stent can provide a permanent scaffold across the aneurysm neck, which may prevent coil prolapse into the parent artery and allow for safer packing of the aneurysm with a denser coil mesh. In addition, the stent may help prevent recanalization by hemodynamic changes and stent endothelialization. [17]However, as a new device, there is limited knowledge about the complications and the long-term effects of the stent on the cerebrovasculature.
We have found that the overall procedure-related complication, morbidity and mortality were 14.2 %, 4.2 % and 1.3 %, respectively, and that a cumulative excellent or good clinical outcome rate is 88.3 %, which reflect better outcome than open surgical series. Most of our complication cases were treated during the first half of our experience period.
Ischemic event is a significant problem in periprocedural period. Usually, thromboembolism is the main cause of ischemic event. [18] Park observed nine thromboembolic events among 27 complications during coiling of 118 ruptured aneurysms.[19] The acute or subacute thrombogenicity of endovascular stents also represents an important limitation with respect to the treatment of aneurysms and appears to be the main drawback of stent-assisted coil embolization. [20-24] According to these literatures, incidence of thromboembolic event ranged from 4.2 to 17.1%. In our series, we observed a relatively low rate of thromboembolic events (5.4%), with 1.6% morbidity and 0.4% mortality. Our findings suggest stent-assisted coiling does not increase the risk of thromboemblism with proper management, which is similar to those of some reports. [18]This low rate of thromboembolic events has been achieved with enough heparinisation, dual pre- and postoperative antiplatelet therapy, shorten duration of endovascular manipulation, and sufficient prevention from injection of embolus into circulation. Additionally, the use of bioactive coils (e.g. Matrix coil) in conjunction with the stent should be avoided. Partially thrombosed aneurysms can be coiled using the balloon remodeling technique, and then the stent is delivered across the aneurysm neck at the end of the procedure. Once thromboembolism is noted, local intra-artery administration of abciximab or urokinase and mechanical disruption of clot with microwire are necessary. Sometimes mechanical dilation with balloon angioplasty can be performed.
Delayed in-stent stenosis is likely a rare event. Biondi et al [16] reported one (2.4%) asymptomatic stenosis of the parent artery at the proximal end of the stent, which was observed on follow-up angiography and successfully treated by angioplasty. Fiorella et al [25] reported a 5.8% rate (9 of 156 patients) of delayed moderate to severe (>50%) in-stent stenosis after 2 to 9 months, of which two patients needed retreatments to control ischemic symptoms. In our series, in-stent stenosis was confirmed in two patients, one of whom underwent angioplasty. The Wingspan study[26], reported a rate of in-stent stenosis of 29.7% and an additionally 4.8% of in-stent thrombosis after an average of 5.9 months on the treatment for symptomatic intracranial atheromatous disease. Endothelian disruption and denudation of the vascular wall during stenting in the absence of functional endothelium in an atheromatous vessel resulting in neointimal tissue formation may play an important role. This action is mediated by proliferation and activation of regional smooth muscle cells. It is unclear whether similar reaction is also responsible for delayed in-stent stenosis after the stent placement, which has much lower radial force, as an aneurysm neck bridging device covering the normal vessel wall. Additional follow-up will be critical to delineate the incidence of this phenomenon.
Delayed ischemic neurological deficit associated with vasospasm is a major cause of morbidity and mortality in patients with SAH. Symptomatic vasospasm is reported in 22–40% of patients with SAH, resulting in 34% morbidity and 30% mortality rates. [27-31] Murayama et al [32] reported a 23% incidence of symptomatic vasospasm after endovascular coil occlusion of acutely ruptured; this rate compares favorably with that found in conventional surgical series. Gruber et al[33], however, noted an increased incidence of vasospasm-related infarctions in patients treated endovascularly (37.7% vs. 21.6% with surgery). However, when patients with Fisher grade 4 and Hunt and Hess grade V lesions were excluded, the difference between the treatment groups was no longer significant. Other authors [19,34,35] have not found an increased risk of vasospasm with endovascular therapy as well. They concluded that the type of treatment was not associated with an increased risk of cerebral vasospasm. Rabinstein et al [36] studied 415 consecutive patients with aneurysmal SAH. Symptomatic vasospasm occurred in 39% treated with surgical clip placement and 30% treated with endovascular coil occlusion. In a univariate analysis, the incidence of vasospasm did not differ between the groups. In our study, the incidence of symptomatic vasospasm among 129 patients with SAH was 18.6%. It seems that the stent-assisted coiling does not increase the risk of symptomatic vasospasm, compared with open clipping and other endovascular techniques.
Different stategies regarding the timing of stent deployment in relation to coiling are practiced. In majority of reports, stenting was performed before coiling in the same session, including the sequential technique and the jailing technique.[9, 20-22] The strategy of stenting after balloon-assisted coiling is less frequently reported. [21, 16] In our series, several main options were practiced and the strategy of stenting before coiling was predominantly used. On comparative analysis of stenting before coiling versus stenting after balloon-assisted coiling, the complete occlusion rate did not show significant difference ( P>0.05, Χ[2] test ). However, balloon remodeling technique have some drawbacks according to our experience (maybe bias). Coil mass herniation is sometimes a limitation of balloon-assisted coiling once the balloon is deflated or removed. Repeated inflation and deflation of the balloon may cause intimal damage[37], which has occurred in our series. Furthermore, balloon inflation, which results in complete blood flow arrest in the parent artery, can increases the risk of thromboembolic events[38, 39], although this is still controversial. In our series, a novel stent-assisted coiling technique, the semi-deployment technique, was used in 31 aneurysms. Compared to the conventional techniques, this technique has several advantages. First, it increases maneuverability of the coiling catheter, allowing more controlled coil positioning. Second, the coil basket can be optimized and there is less likelihood for coil migration when the aneurysm neck is narrowed by the partially deployed stent. Last, it decreases the risk of the stent herniating into the aneurysm in treatment of large or giant aneurysm. Nevertheless, further experience is necessary to determine complication rate and suitable selection of patients to different strategies.
There are controversial reports about benefit of the dual antiplatelet therapy. [40, 41] The optimal regimen has not yet been defined. It is intuitive that the aneurysms are fragile and parent vessels are less healthy in patients in the acute phase of SAH. A meta-analysis of published reports, from retrospective data has also suggested the risk of intraprocedure rupture is significantly higher in patients with ruptured aneurysms. Our data suggest that the incidence of intraprocedual rupture is significantly higher in patients with ruptured aneurysm (P<0.01), and the incidence of thromboembolism between those with and without ruptured aneurysms is not statistically significant. This finding may advocate for a more cautious preprocedural antiplatelet treatment for patients with ruptured aneurysms. Katsaridis V has reported a very low thromboembolic complication rate (1.8%) in the Neuroform2 stent-assisted embolization of 54 aneurysms without antiplatelet pretreatment.[40] In our practice, it is after general anesthesia that dual antiplatelet treatment (aspirin 300 mg and clopidogrel 225 mg via nasogastric tube) initiates for accurately ruptured aneurysms.
Because of a prolonged posttreatment antiplatelet regimen, if there is any evidence that the patient will need EVD surgery due to SAH, this should be done before interventional therapy. On the basis of our experience, this might not only prevent fatal increase of intracranial pressure, but might also reduce subsequent bleeding complications if the patient is on a strong anticoagulation and antiplatelet regimen. However, in our series, a total of seven patients underwent additional emergent surgical treatment after interventional therapy. Five patients received EVD and two patients underwent decompressive craniotomy. Protamine chloride and minirin were used to reverse the anticoagulation and antiplatelet drugs before surgery. Fortunately, there were no surgical complications or special difficulties due to abnormal intraoperative bleeding during the operation. Taking into account relatively more ischemic events, a more aggressive anticoagulation and antiplatelet therapy should be used after the procedure.
In our opinion, the risk of periprocedual antiplatelet therapy should be weighed against the potential benefit and that antiplatelet and anticoagulation therapy should be tailored according to the results of ongoing researches.
The goal of aneurysm treatment should be permanent exclusion of the aneurysm from the circulatory system to prevent rupture or rerupture. Aneurysm recanalization must be acknowledged as a failure to achieve this goal. However, not a single one of treated aneurysms experienced rehemorrhage during the follow-up time, in our series, despite incomplete occlusion and recanalization. Lylyk et al reported that follow-up was obtained in 63% of their patients and stressed that there were no cases of repeated hemorrhage.[21] Biondi et al [16] also reported that no aneurysm bled after stent-assisted coiling during the follow-up period, though complete or subtotal aneurysm occlusion was not always obtained. Based on these results, we therefore conclude that the risk of rupture after occlusion of aneurysms may be substantially reduced. Aneurysm follow-up angiography and reembolization, if necessary, still should be done, though. Fiorella et al [22] reported initial (3-6 mo) angiographic follow-up in 58% of aneurysms treated with Stent-assisted coiling showing progressive thrombosis in 52% of patients, recanalization in 23%, and no change in 25%. In the series of Biondi et al [16], recanalization was observed in 13% of wide-neck aneurysms treated with stent-assisted coiling. We observed 23 cases (14.5%) of aneurysm recanalization on follow-up angiograms, which was acceptable compared with most publications. In our experience, the recanalization rate of none-stented wide-neck aneurysms is high. Murayama et al reported that the overall recanalization rate of coiling without stenting was 20.9%.[6] A stent placed across the aneurysm neck may prevent recanalization because of the hemodynamic changes and stent endothelialization. The stent is used not only to assist in coil delivery, but also to prevent recanalization. In our series 60.9% (14/23) of the recanalized aneurysms were not initially completely occluded (class2 or class3) and no recanalization occurred in small aneurysms which was completely occluded. Therefore, sequential follow-up angiograms are mandatory, especially for those aneurysms showing incomplete occlusion. In our series, no adverse events were shown on follow-up angiograms or occurred during retreatment with detachable coils. Recently, Renowden et al [42] and Henkes et al [43] reported complication rates of 2% to 3% in their large series of retreatment of previously embolized aneurysms. Follow-up procedures can be done safely, and the risk from retreatment with detachable coils does not negate the advantages of initial use of coil embolization. During initial treatment discussions, patients should aware that wide-neck aneurysms, especially large and giant ones, may require multiple treatment and will certainly require a significant course of long-term follow-up.
Our study indicates that stent-assisted coil embolization of intracranial aneurysm is a safe technique with low morbidity and mortality rates. Our results are consistent with those reported in the literature (Table 5). The main cause of morbidity and mortality is thromboembolism (38.2% of all procedure-related complications are thromboembolic in our study). In our hand, this technique does not increase the risk of symptomatic vasospasm, compared with open clipping and other endovascular techniques. The recanalization rate is relatively low. The delayed in-stent stenosis seems a rare complication, compared to stent deployment in atherosclerotic lesions. Nevertheless, additional, large series with long-term follow-up are necessary to determine the durability of these promising results.
Series (ref no) | No of patients (aneurysms) | Rate |
Fiorella et al. 2004 (15) | 19 (22) | 10.5% thromboembolism rate (10.5% thromboembolic morbidity) |
dos Santos et al. 2005(17) | 18 (17) | 23.5% technical complication rate (5.8% morbidity) |
Lee et al. 2005(23) | 22 (23) | 9.1% procedure-related complication rate |
Akpek et al. 2005(20) | 32 (35) | 25% adverse event rate, 9.3% morbidity, 3.1% mortality |
Lylyk et al. 2005(21) | 50 (50) | 8.6% morbidity, 2.1% mortality |
Katsaridis et al. 2006(38) | 44 (54) | 4% stent-related complication rate |
Biondi et al. 2007(16) | 42 (46) | 4.3% procedural morbidity, 2.2% procedural mortality |
Yahia et al. 2008 (3) | 67(67) | 7.4% procedure-related complication rate |
Mordasini et al. 2008 (44) | 18(18) | 22.2% thromboembolism rate( no morbidity and mortality) |
Wajnberg et al. 2009 (24) | 24 (24) | 4.2% procedure-related thromboembolism rate |
Seadt J et al. 2009 (45) | 42(42) | 2.4% procedural morbidity |
Published complication rates for Neuroform stent-assisted coiling of intracranial aneurysms
Redox flow batteries (RFB) are electrochemical reactors suitable for storing electrical energy by chemical reactions. [1] Depending on the technology used, this reaction can take place at elevated temperatures and/or in aggressive media, with an electrochemical potential superimposed. In recent years, the technical requirements on materials and components of the reactor of the Redox flow battery have therefore become more and more demanding. The battery unit consists of many stacked cells which are connected in series to a Flow battery stack. Each cell in turn consists of various components such as the proton exchange membrane, seals, frames and the conductive bipolar plate which provides the connection from cell to cell up to the end of the stack where the generated current is collected.
RFBs, in particular vanadium redox flow batteries (VRFBs), have now reached a considerable degree of technical maturity and the systems are available on the market through many suppliers. However, due to a high remaining cost structure - partly due to a lack of economies of scale - the profitable market introduction of flow batteries still suffers from a high market acceptance.
On the one hand the membrane is considered the heart of a redox flow battery. On the other hand, the bipolar plate is one of the key components of an RFB. However, the Bipolar plate is important, since the plate has an impact on the complete systems, as far as total dimensions, total weight, thermal and electrical properties of the stack and thus of the system is determined by the bipolar plate technology. [2]
As already mentioned, the chemical conditions for the materials used in redox flow batteries are challenging. [3] Most systems are operated between 40°C and 60°C in a liquid of dissolved vanadium salts in sulfuric acid. Besides the Vanadium-technology, there also some other technologies (metallobased or organic RFBs), which will not be further considered.
Due to these harsh conditions, superimposed by an electrochemical potential, graphite-based bipolar plates with polymeric binders are used in almost all applications in these battery stacks. The graphite composite plates are an unbeatable material in terms of stability under the above-mentioned corrosive conditions, and the cost-intensive coated metal plates have no chance.
They have been operated very adequately several times over the years. However, due to an intrinsic fragility caused by a high filling load with graphite, graphite composite plates require a greater thickness than metal plates, resulting in more weight and volume of the stack. From a cost point of view, the membrane is certainly considered the dominant part of the redox flow battery stack. However, the bipolar plates tend to be underestimated both in terms of their technical requirements and, in particular, their contribution to the cost structure.
Graphite composite based bipolar plates are manufactured using highly filled compounds [2]. They contain fillers like graphite and/or other electrically conductive carbons incorporated in polymers performing as a gluing binding matrix. The key challenge is the competing interaction between electrical conductivity - achieved by the carbon component - and mechanical stability as well as liquid tightness which is provided by the binding polymer.
The compounding process is the first step to produce highly filled, electrically and thermally conductive pellets for the subsequently following step of forming bipolar plates.
Both compounding and molding processes, which can be injection molding, compression molding or continuously extrusion, are very sensitive to process parameters and need to be carefully controlled. The objective is to manufacture bipolar plates in large volumes and high quality more or less like standard plastic parts. Only by using price cost attractive materials and the consequent focus on process automation by higher volume, the bipolar plate can contribute significantly to a better market acceptance of RFB.
Besides the bipolar plate, the gasket is a very important component of the battery stack and tends to be heavily underestimated. It plays a key role in the mechanical properties of the stack. Inappropriately selected gasket materials may cause cracks in the bipolar plates or may affect the membrane-structure negatively. Despite the fact that the gasket has to seal the stack, the cooperation with other stack components and their cumulative tolerance effects have to be on focus for the stack design and for the operation of its.
The same which is evident for each component is also obviously for the gasket; they have to be cost attractive. Therefore, in some research projects, it is the objective is to suspend gaskets completely and use welding or bonding processes instead.
Technically, the bipolar plate of a RFB stack has to accomplish the following functions [3, 4]:
conduct electrical current,
conduct heat and distribute coolant in a eventually incorporated cooling flow field,
provide mechanical stability of the stack,
prevent permeation and leakage
However, the functions of the gasket are completely different. The main functions of gaskets in a RFB stack are [5, 6]:
sealing and leakage prevention of anode and cathode area,
sealing and leakage prevention of cooling plates,
compensate tolerances and dimensional changes during stack-assembling caused by interaction with all stack components.
Based on the technical functions described above, a comparison to other technologies is necessary: The Fuel Cells: The US department of energy (DoE) suggested development targets for fuel cell components as shown in the Table 1 for bipolar plates [8]. Although these data are based on communication and data from conventional low temperature PEM fuel cell developers, most of the targeted values can be directly transferred to Redox-Flow technology.
Technical property | Units | Targeted value |
---|---|---|
Plate weight | < | |
Electrical conductivity Depending on type | > | |
Thermal conductivity | > | |
Flexural strength | > | |
Shore D hardness | > | |
Temperature resistance Thermo-mechanical test | > | |
Acid uptake Depends on application or technology | low |
Benchmarks for bipolar plates in redox-flow applications defined by DoE [7] and experiences from customer requirements from Eisenhuth GmbH & Co. KG.
Additionally, the chemical resistance of the bipolar plate can be characterized by measuring the corrosion current under a potential typical for RFB and using sulfuric acid or something suitable (depending on application as an electrolyte). The detailed parameters and development objectives of this corrosion test are still subject to technical discussions and depend on the anticipated application of the plate. A similar table of functional requirements can be set-up also for gasket materials in RFB.
The gasket material has to be resistant against the selected electrolyte and environment under operating conditions. This is qualified for example by comparison the mechanical properties of recently produced and altered samples. It has to be noted that the values mentioned in Table 2 are for orientation and refer to standard elastomer materials available on the market. Based on these technical requirements, an appropriate feedstock respectively materials for both bipolar plates and gaskets have to be selected.
Technical property | Units | Targeted value |
---|---|---|
Density | ||
Electrical conductivity Depending on type | < | |
Shore D hardness | < | |
Compression set | < | |
Temperature resistance Thermo-mechanical test | > | |
Chemical stability Depends on RFB-type | Resistant against the used chemical environment; no or low changes in properties (typically mechanical) |
Proposed benchmarks for gaskets in RFB based on fuel cell requirements [9] and experiences from customer requirements from Eisenhuth GmbH & Co. KG.
As mentioned above, composite bipolar plates consist of a binder polymer, which is highly filled with a conductive carbon component. Typical compositions are >80 wt.% conductive filler and < 20 wt.% binder polymer. Compounding, processing and manufacturing is substantially different from conventional polymers due to the high content of filler material in the compound [10]. The function of the carbon filler is to provide electrical and thermal conductivity.
Therefore, a three-dimensional percolating carbon structure is required. Usually, the main carbon component of the plate is synthetic graphite and the second material is carbon black. For producing plates, several options are possible:
Compression molding
Injection molding
Plate Extrusion
Foil Extrusion
In all methods, after removal from the process certain after treatment procedures may be necessary. Either to remove the ‘skin’ of the mold release agent from the surface of the plate or as noted in Derieth et al. [9, 10] to remove an accumulation of polymer from the injection. Or compression molding skin.
In general, two different concepts of polymer binders can be applied in bipolar plates. First, the binder material can be polymerized or cross-linked in-situ in the composite during molding of the plate (resin method). The used polymer is thermosetting, which provides good mechanical properties at elevated temperatures and often a relatively easy processing. [11]
Second, a thermoplastic polymer material can be used in the compounding process (thermoplast method). Since the most materials in RFB are thermoplastic materials, in the following the focus will be also in this consideration. The polymer has to be selected with sufficient chemical, mechanical and thermal stability (e.g. data from [11]). Several material candidates are available on the market in high quality and well-defined configurations for different processing methods and applications due to the usage of additives like waxes, minerals or fibers.
Figure 1 shows the well know pyramidal classification for more than a handful of popular plastics.
The plastics pyramid preferred materials for RFB applications are semi-crystalline materials such as PP, PE and PVDF [9].
While graphite is generally the major filler for bipolar plates to achieve a sufficient conductivity, several other carbon additives can be employed in order to boost conductivity properties of the composite material. Examples for such additives are highly conductive carbon nano tubes (CNT), high surface carbon blacks (CB) or multi-layer graphene nanoplatelets. [7]
Due to its crystalline layer structure graphite is inherently anisotropic in its physical properties e.g. electrical conductivity or its mechanical behavior. Electrical conductivity is being provided by the mobility of electrons within the graphite layers of each platelet. Contrary to the conductivity along the layers, graphite is perpendicular to these layers an electrical insulator. Thus, the bipolar plate manufacturing process should ‘promote’ different orientations of the platelets forming isotropic physical properties of the macroscopic plate material. Some additives such as carbon blacks are helpful to increase the number of conductive paths in the carbon-polymer-system. The nano-sized carbon blacks do function as a ‘gap-filler’ in the insulating polymeric matrix between the micro-sized graphite particles and this in consequence increases the overall material conductivity significantly. [7]
The overall conductivity in a bipolar plate is generated by a three-dimensional percolating network which consists of conductive particles. The carbon-binder system is always inhomogeneous and can be considered as a two-phase system of conductive carbon paths bonded in a polymer matrix as shown in Figure 2. The structure of the material highly depends on the chemical composition and not less important on the kind of the chosen processing-approach (compounding, molding, extruding…) and the therefore used parameters. The complete processing chain – from the raw material to the molded plate – has to be carefully controlled to ensure consistency and reproducibility of the bipolar plates.
Polarization microscopy of polished surface from bipolar plate with 80 wt.% graphite content. Particles (black) are locatable in polymer matrix (white).
Carbon blacks can be formed in the gas phase by thermal decomposition of hydrocarbons under different conditions [11] and this results in a broad variety of materials with differences in surface area, hydrophobicity and conductivity. The different carbon black grades are then available for the adequate application and function.
Keeping this in mind it has to be considered that high surface carbons are more disposed to (undesired) carbon corrosion effects than graphite-based materials, thus their positive conductivity effect has to be balanced against long term stability requirements.
Another important aspect of carbon materials is purity. Since most fuel cell membranes and catalysts are highly sensitive against contamination with Iron-ions and other metal residuals, the raw materials for bipolar plates have to be carefully characterized with respect to their contamination level. The carbon or graphite type also mainly determines bipolar plate’s properties like porosity, phosphoric acid uptake or corrosion and hydrophobicity, both regarding the surface and the bulk. [11, 12]
At status quo, the amount of waste caused by the production of bipolar plates – an inhomogeneous system consisting of plastic and carbon –is significantly higher when compared to a fully implemented commodity plastic production process. [13] The waste accrues in form of rejects from production, which can be lowered by optimization processes, but also in form of gates, which are necessary for production and dimensioned by material properties. In addition, the systems in which the material is used have a limited lifespan, so the demand of reusage of the parts made of graphite compound or the compound itself is conceivable.
On the other hand, there is the possibility to use secondary materials as feedstock of the graphite compounds to substitute fully or partially the conventional fillers. Conductive fillers like synthetic graphite are valuable resources being produced via different thermal processes, which are similar to other thermal processes e.g. some recycling processes for various other wastes. Some of these processes generate in some degree useful carbon materials. [13]
These circumstances and opportunities result in an increasing development of recycling methods with the consequence of a property upgrade of the carbon by combining lower general production costs. In the best case these carbons are suitable for bipolar plates. In Figure 3 the principle of the different recycling opportunities are being described.
Scratch of flow diagram for resources from recycling and secondary sources. The primal structure is from plastic treatment [14, 15, 16]. The obvious barriers are the contaminations and changes in material properties caused by multiplied processing.
Certainly, the final criteria of success for any bipolar plate is the in-situ control of performance and stability under real RFB conditions. However, RFB are highly complex systems with numerous sources of inconsistency. Thus, standardized ex-situ bipolar plate characterization is required for material development and quality control. Several test methods are well established for bipolar plates and some are presented below. The list of test methods is not considered to be complete.
Clearly, electrical conductivity both in-plane and through-plane is one of the most important properties of the bipolar plate. Despite most fuel cell (component) and battery laboratories have access to electrical conductivity testing equipment, by now there is no generally standardized test method for bipolar plates for RFB, and comparing results from different sources can show significant differences, even though the same samples are tested. One of the main reasons may be surface effects and pre-treatment of the sample. As shown in the Figure 4, Eisenhuth has implemented a testing system for this application, which is suited for local in-plane conductivity testing with the option to measure several times at different locations on the plate.
Testing device and method for electrical conductivity measurement at Eisenhuth GmbH & Co. KG.
The in-plane conductivity device allows for a conductivity mapping over a sample area of 750x300 mm. Thus, the characterizing of the plates with respect to the degree of homogeneity during production is possible. Conductivity mapping is an important tool both for quality control as well as and furthermore for the material and process development.
For graphite composite plates it is well known that compounding and molding are highly sensitive to process details and may generate inhomogeneous structures on the surface and/or in the inner core of the material. Certainly, the development target is a homogeneous distribution of conductivity with only minimal deviations between different points on the bipolar plate.
For PPG86 and BMA5 or BMA6 plates the compounding and manufacturing process in hot pressing are established and well controlled, and the conductivity mapping shows an even distribution. Irregularities in the conductivity are in some processes unavoidable because of the process-depending-orientation of the particles through different processing influences. For example, in injection molding the filler particles orientate differently from the core to the surface of the produced parts, which results in different conductivities measured In-plane or through-plane. In addition, the regions which will be filled lastly in injection molding show a higher average conductivity compared to the gate region.
A conductivity mapping of a second process example for a PPG86 based plate is shown in Figure 5. This specific plate is produced by plate extrusion. The border area of the plate parallel to the flow direction during the extrusion process seem less conductive.
In-plane conductivity mapping of a PPG86 based bipolar plate made by extrusion by another company who is also active in the field of redox flow batteries. The material shows a higher resistivity at the outside areas caused by the manufacturing-process. The results are corrected with finite size corrections for 4-point probe measurements. [17].
In terms of hot pressing – a process with a certainly low flow – these described irregularities are more dependent from the overall process stability and experience of the manufacturer. Development in the field of hot pressing by Eisenhuth GmbH & Co. KG in the last years are focused mainly in material research with the aim of reaching higher conductivity, larger plate designs and simultaneously easier production.
In Table 3 technical properties for bipolar plates made by hot pressing are shown. The data is measured with the shown in-plane conductivity measurement device and specimen according DIN EN ISO 527 tested on a universal testing device and a microbalance.
Technical property values | 2018 | 2020 | ||
---|---|---|---|---|
PPG86 | BMA6 | PPG86 | BMA6 | |
Density ( | 1.8 | 2.1 | 1.8 | 2.0 |
Electrical conductivity ( Depending on type | 96.2 | 192.3 | 185.2 | 312.5 |
Flexural strength ( | 21.1 | 31.8 | 22.4 | 31.7 |
Technical properties from databases from Eisenhuth GmbH & Co. KG.
The comparison between the results shows that the improvement of the standard products from Eisenhuth GmbH & Co. KG has led to an increase of the electrical conductivity from around 75%. But the mechanical behavior seems similar. This is due to optimizing process parameters and periodic testing of new raw materials.
As described above the material used for the bipolar plates in RFB applications is made out of plastics and conductive fillers like graphite. During RFB operation the bipolar plates are exposed to normal temperatures, such as 40°C. Consequently, all raw materials used for plate manufacturing have to resist approximately 40°C.
Parallel to the shortage of the raw materials, the Vanadium-RFB technology has to compete regarding cost- and technology-aspects to other technologies, in particular with the lithium ion storage technology. Knowing this background, it is more than advisably to look out for alternative materials. Thus, the Eisenhuth GmbH & Co. KG is investigating together with a consortium alternative material sources, in particular from the recycling sector. Two potential processes which produces carbon materials are shown in Figure 6.
Principle of producing carbon black and graphite from used tires (A) and in a hydrogen production in a methane cracking process (B). [13, 16, 18].
Both processes separate carbon in form of agglomerated particles. Tyres consists of rubber filled with carbon pigments to strengthen the material. By the oxygen-less combustion of tyres the carbon will be released and during the pyrolysis process it is being formed to agglomerates.
During methane cracking – a process to produce hydrogen - carbon can agglomerate on particles, which function as. The particles consist of contaminations of the used feed gas or are part of the used catalyst. [17]
The samples are called CB-RC for the tyre recycling carbon black and CB-MC for the methane cracking carbon black. Resulting curves of the mass loss over the temperature of TGA from different carbon blacks are shown in Figure 7. Samples of conventional carbon blacks are called CB-C.
TGA data from different carbon blacks. Conventional CB (CB-C) and CB from secondary sources (CB-MC and CB-RC) are compared. The differences in combustion temperatures and contents of ash are significant.
The thermogravimetric analysis (TGA) can be used in order to determine the combustion and vaporization temperatures of the materials and allows to quantify the contents of different materials in the compound. [19]
During TGA a sample is heated under defined conditions such as gas environment and heating rate. The weight loss as well as the temperature (in correlation to the weight loss) of the sample in the oven is being determined. The TGA is used at Eisenhuth as an instrument of permanent quality control of the process. It also can be used, to get more information about the compound material.
The TGA curves show that the secondary materials contain a high content of ash. The influence of the ash is at that point unknown. At best it does not influence or at least it has a minor influence on the properties of the compound respectively the plates. In the worst case some critical contaminations are soluble or volatile and will damage the system, in which the material is used. The details are shown in Table 4. The average combustion temperature is extracted from the curves at the point at which 50% of the weight of the combustible mass is lost.
Carbon black type | Average combustion temperature / | Rest mass (Ash) / |
---|---|---|
CB-C-I | 784.4 | 0.13 |
CB-C-II | 691.4 | −0.29 |
CB-MC-I | 684.7 | 8.66 |
CB-MC-II | 666.4 | 14.86 |
CB-MC-III | 695.8 | 10.18 |
CB-RC-I | 558.4 | 19.52 |
CB-RC-II | 541.4 | 12.45 |
Results of TGA from different CB-types. The CB tested are conventional (CB-C), products from methane cracking (CB-MC) and products from Tyre recycling (CB-RC). The average combustion temperature is at the point of 50% weight loss of the combustible mass.
The second that stand out is the difference of the combustion temperatures of the tested CB. A lower combustion temperature under the assumption that the tested materials consists of similar carbon structures is an indication for a higher surface area [20]. It is described that the surface area – normally measured for CB according ASTM D 2414 with dibutyl phthalate (DBP) – has an influence in the percolation threshold and the resulting conductivity of the corresponding compound. The percolation threshold is the small zone in which the compound receives a mayor increase in its electrical conductivity by only adding a very less of filler content. [21]
In order to characterize the influence of the different CB types on the conductivity, the secondary CB are integrated and evaluated in various testing and production series to compare the new materials with the current neat carbon black. The Table 5 shows the results of conductivity measurements like described above from different compounds, in which the CB types are used. For comparison individual references from the mentioned testing and production series are listed in the same table. The compounds are made by combining different polymers mostly PP with graphite. Some of the graphite is replaced with the different CB to keep the recorded filler content at the same level for all.
CB used in compound | Filler content / | Compound conductivity / | Reference conductivity / | CB used in Ref. |
---|---|---|---|---|
CB-C-I | 78 | 28.3 ± 2.0 | 13.2 ± 2.5 | None |
CB-C-II | 75 | 12.9 ± 0.9 | < 1 | CB-C-I |
CB-MC-I | 80 | 11.3 ± 1.2 | < 1 | None |
CB-MC-II | 80 | 10.6 ± 2.5 | < 1 | None |
CB-MC-III | 80 | 12.0 ± 1.5 | < 1 | None |
CB-RC-I | 75 | 8.9 ± 0.7 | 18.7 ± 0.6 | CB-C-I |
CB-RC-II | 75 | 9.0 ± 0.8 | 18.7 ± 0.6 | CB-C-I |
Results of conductivity measurements from different compounds. Partially consisting of the described CB types from conventional and secondary sources compared to individual references produced parallel the tested compound mixtures.
It can be observed that the impact of the secondary CB on the electrical conductivity is noticeable, but far less for CB-MC and CB-RC-types than the qualification by the TGA suggests. The compounds consisting the CB-MC types have a relatively low conductivity compared to standard materials but the reference compound with the same filler content has no measurable conductivity, therefore the CB-MC types seem to reduce the percolation threshold for the filler in the compound. The CB-RC types have compared to conventional CB a smaller impact on the conductivity because half the value of the CB-C-I consisting reference compound with the filler content of 75 wt.% has been measured.
The qualification by the TGA was fitting for the conventional types. Whereas the high differences between the prognosis and the measurement results for the secondary CB types are unexpected and a high level of uncertainty remains. The reason of these differences can be the high content of probably non-conductive contamination or different carbon structures of the particles. Both reasons are possibly responsible for a way lesser combustion temperature during TGA-measurements. The higher the lever of amorphous carbon and impurities so lower the combustion temperature and the achievable level of conductivity.
Since many years the fuel cell developers invested tremendous efforts in improvement and technological readiness of the core components, such as membranes and electrodes configuration. However, within the last years the gasket material was recognized more and more as an underestimated component. Despite the gasket does not directly contribute to the electrochemical processes, inappropriate gaskets can cause leakages. [6]
The increased use and establishment of the systems on the market, primarily among consumers, has resulted in a focus on safety issues during consumption and error sources during mass production.
Common hard gaskets support well defined gaps, however may be compromised in their sealing properties, do not compensate tolerances very well and may put mechanical distortion on the bipolar plates, which can cause cracks or breaking after a long time. On the other hand, with soft gaskets it is more difficult to control the performance of the system cause of limitations in parameters like pressure. These descriptions are analogue to RFB systems.
In general, like the other RFB components the gaskets have to resist temperatures up to 70°C, electrolytes like sulfuric acid or other materials of RFB systems like bromine and contact to electricity. Fluoroelastomers (FKM) and ethylene propylene diene monomer rubber (EPDM) are most likely the materials of choice for several applications.
For certain applications EPDM might be a cost-efficient alternative for systems which can handle the stiffness of this rubbers. The arguments clearly show that gaskets are a highly customized component for each stack manufacturer. For overview, some typical gasket properties for a broad variety of materials are shown in the Table 6.
Description and Unit | TPS | TPV | TPU | TPO | EPDM | SI | FKM | HNBR |
---|---|---|---|---|---|---|---|---|
Hardness Shore A | 2–95 | 20–95 | 2–85 | 65–95 | 25–85 | 25–85 | 50–90 | 40–90 |
Temperature range | −50 / +120 | −40 / +130 | −40 / +85 | −40 / +70 | −50 / +100 | −70 / +200 | −20 / +220 | −30 / +150 |
Steam resistance | — | — | — | — | ++ | ++ | ++ | ++ |
Oil resistance | + | + | — | + | — | + | ++ | ++ |
Acid /bases resistance | ++ | ++ | 0 | ++ | ++ | — | ++ | + |
Gasket material overview with typical physical properties and behavior in system specific conditions used by Eisenhuth GmbH & Co. KG.
Along with the rubber materials like silicone (SI), hydrogenated nitrile butadiene rubber (HNBR), EPDM and FKM thermoplastic elastomers (TPE) in form of styrenic block copolymers (TPS), thermoplastic vulcanizates (TPV), thermoplastic polyurethanes (TPU) and thermoplastic polyolefin elastomers (TPO) are listed. These thermoplastic-elastomers have similar properties to rubber but can be processed like “common” thermoplastics and can be softer if required. This has the advantage of easier manufacturing and recycling of the material as well as a broader range for applications.
In order to supply consistent gaskets with appropriate tolerances the viscoelastic properties of the gasket prepolymers and thermoplastics are an important parameter. A low viscosity is beneficial for processing. For plastic materials usually the mold flow rate or mold flow index are specified by the supplier, supporting the manufacturer for plastic parts with processing-relevant- information and –parameters. However, these data are ‘standard data’ and not always compatible with the molding conditions or equipment at the part manufacturer.
In addition, for rubber materials or their pre-polymers and thermoplastic elastomers these data are not available in most cases, because of their impacting viscoelastic behavior. Therefore, Eisenhuth developed a phenomenological test method to characterize polymer materials with respect to processability. In this test, a melt of the used pre-polymer or thermoplastic is pressed into a spiral-shaped mold with a defined pressure under process-relevant temperatures.
The viscous melt flows into the spiral mold and finally stops, when the applied pressure is equal to the ‘back-pressure’ in the mold. The reason therefore is the higher lever of the progressing polymerization, vulcanization or solidification of the melt. The length of the helix can be correlated to the viscosity and consequently to the processability. The longer the helix the lower the viscosity. This is helpful to find the processing ranges of materials as far as the viscosity is concerned (Figure 8).
Spiral mold for characterization processability by injection molding by Eisenhuth GmbH & Co. KG.
As mentioned, the length of the spiral is an good indicator for the processability. This test has been performed with a variety of potential gasket materials to achieve a data baseline. The values are shown in Figure 9.
Results of injection molding in spiral mold.
The results show that processability depends strongly on the material but different types of the same material have also high differences. Exemplarily shown in the Figure the good processability of some types of thermoplastic elastomer materials cannot be reached by the measured processability of rubber materials.
The processability of the thermoplastic elastomers is convenient but it is necessary to qualify the mechanical and chemical stability of the materials. The called rubbers are commonly used in different applications such as fuel cells and chemical industries, and their long-life behavior is already known.
To ensure the stability of the materials specimen according DIN EN ISO 37 are made and treated in this example in vanadium electrolyte for VRFB applications. The electrolyte is positive charged, so the most aggressive species of vanadium ions is to 1.65 mol/L concentrated in 4 mol/L sulfuric acid. The specimens are treated the same time for around thousand hours and therefore stored in glasses with full surrounding electrolyte. The specimens are tested for tensile strength according DIN EN ISO 37 in a universal testing machine. The resulting Young’s modulus are shown in Figure 10 and are exemplary for the overall changes in mechanical properties of the treated specimens.
Results of tensile strength testing according DIN EN ISO 37. The tested materials are different rubbers and thermoplastic elastomers. The untreated specimens are directly tested after production. The second data is generated after exposure of specimens with aggressive vanadium electrolyte used in VRFB.
It is shown that the stability of the rubbers in the specific environment is good. The modulus is low but there are no major changes measured. In average the thermoplastic elastomers are different to the rubbers. Most of the materials and material types have a higher modulus with low changes. TPU seems not suited for the application, moreover one indication are high changes such as superficial cracks in the surface of the sealing.
In this chapter the basics and advantages of graphite bipolar plates could be presented in connection with current research topics at Eisenhuth regarding the reduction of production costs and the related easier market introduction of RFB. Furthermore the suitability of easy to process thermoplastic elastomers as sealing material in RFB was shown.
It was explained that the proposed targets for material properties are not fully achieved, but that progress in materials research is possible. For example, the electrical conductivity of standard materials for RFB could be optimized by about 75% in recent years.
Options to reduce costs through recycling methods and use of secondary resources were discussed. It could be shown that the substitution of commercial carbon types such as synthetic graphite by secondary materials for composite production is possible.
The differences in the processability of rubber types and thermoplastic elastomers were shown by tests in a correspondingly designed injection mold. The chemical stability of some types of thermoplastic elastomers is tested for VRFB.
The authors acknowledge fruitful collaboration, extensive test work and the positive relationship to Technical University of Clausthal, German Aerospace Center Oldenburg (Institute of Networked Energy Systems) and Research Center of Fuel Cell Technology (ZBT) in Duisburg.
Public funding is gratefully acknowledged from Federal Ministry for Economic Affairs and Energy (Germany) and Ministry of Education and Research (Germany) in cooperation with the project holder Forschungszentrum Jülich in the projects ‘Redox Flow Extrusion’, ‘Re3dox’, ‘Demo-Bio BZ’ and from the State of Lower Saxony in the project “Maleskues” and “Titan Porous Hybrid”.
The authors are part of the company Eisenhuth GmbH & Co. KG, which produces bipolar plates made of graphitic compounds and gaskets for fuel cell, redox-flow battery and heat exchanger purposes.
The shown data are part of the acknowledged public funded projects. The conclusions and statements made are based on the experience of the authors in their specific working fields in the said company.
These Terms and Conditions outline the rules and regulations pertaining to the use of IntechOpen’s website www.intechopen.com and all the subdomains owned by IntechOpen located at 5 Princes Gate Court, London, SW7 2QJ, United Kingdom.
',metaTitle:"Terms and Conditions",metaDescription:"These terms and conditions outline the rules and regulations for the use of IntechOpen Website at https://intechopen.com and all its subdomains owned by Intech Limited located at 7th floor, 10 Lower Thames Street, London, EC3R 6AF, UK.",metaKeywords:null,canonicalURL:"/page/terms-and-conditions",contentRaw:'[{"type":"htmlEditorComponent","content":"By accessing the website at www.intechopen.com you are agreeing to be bound by these Terms of Service, all applicable laws and regulations, and agree that you are responsible for compliance with any applicable local laws. Use and/or access to this site is based on full agreement and compliance of these Terms. All materials contained on this website are protected by applicable copyright and trademark laws.
\\n\\nThe following terminology applies to these Terms and Conditions, Privacy Statement, Disclaimer Notice, and any or all Agreements:
\\n\\n“Client”, “Customer”, “You” and “Your” refers to you, the person accessing this website and accepting the Company’s Terms and Conditions;
\\n\\n“The Company”, “Ourselves”, “We”, “Our” and “Us”, refers to our Company, IntechOpen;
\\n\\n“Party”, “Parties”, or “Us”, refers to both the Client and ourselves, or either the Client or ourselves.
\\n\\nAll Terms refer to the offer, acceptance, and consideration of payment necessary to provide assistance to the Client in the most appropriate manner, whether by formal meetings of a fixed duration, or by any other agreed means, for the express purpose of meeting the Client’s needs in respect of provision of the Company’s stated services/products, and in accordance with, and subject to, the prevailing laws of the United Kingdom.
\\n\\nAny use of the above terminology, or other words in the singular, plural, capitalization and/or he/she or they, are taken as interchangeable.
\\n\\nUnless otherwise stated, IntechOpen and/or its licensors own the intellectual property rights for all materials on www.intechopen.com. All intellectual property rights are reserved. You may view, download, share, link and print pages from www.intechopen.com for your own personal use, subject to the restrictions set out in these Terms and Conditions.
\\n\\nWe employ the use of cookies. By using the IntechOpen website you consent to the use of cookies in accordance with IntechOpen’s Privacy Policy. Most modern day interactive websites use cookies to enable the retrieval of user details for each visit. On our site, cookies are predominantly used to enable functionality and ease of use for those visiting the site.
\\n\\nIn no circumstances shall IntechOpen or its suppliers be liable for any damages (including, without limitation, damages for loss of data or profit, or due to business interruption) arising out of the use, or inability to use, the materials on IntechOpen's websites, even if IntechOpen or an IntechOpen authorized representative has been notified orally or in writing of the possibility of such damage. Some jurisdictions do not allow limitations on implied warranties, or limitations of liability for consequential or incidental damages; consequently, these limitations may not apply to you.
\\n\\nIntechopen.com website content and services are provided on an "AS IS" and an "AS AVAILABLE" basis. Material appearing on www.intechopen.com could include minor technical, typographical, or photographic errors. IntechOpen may make changes to any material contained on its website at any time without notice.
\\n\\nIntechOpen has no formal affiliation to any external sites that link to www.intechopen.com, unless otherwise specifically stated. As such, it is not responsible for content that appears on any such sites. The inclusion of any link to IntechOpen does not imply endorsement by IntechOpen. Use of any such linked website is done solely at the user's own discretion.
\\n\\nWe reserve the right of ownership over our entire website www.intechopen.com, and all contents. By using our services, you agree to remove all links to our website immediately upon request. We also reserve the right to amend these Terms and Conditions and our linking policy at any time. By continuing to link to our website, you agree to be bound to, and abide by, these linking Terms and Conditions.
\\n\\nIf you find any link on our website, or any linked website, objectionable for any reason, please Contact Us. We will consider all requests to remove links but will have no obligation to do so.
\\n\\nWithout prior approval and express written permission, you may not create frames around our web pages or use other techniques that alter in any way the visual presentation or appearance of our website.
\\n\\nIntechOpen may revise its Terms of Service for its website at any time without notice. By using this website, you are agreeing to be bound by the current version of all Terms at the time of use.
\\n\\nThese Terms and Conditions are governed by and construed in accordance with the laws of the United Kingdom and you irrevocably submit to the exclusive jurisdiction of the courts in London, United Kingdom.
\\n\\nCroatian version of Terms and Conditions available here
\\n"}]'},components:[{type:"htmlEditorComponent",content:'By accessing the website at www.intechopen.com you are agreeing to be bound by these Terms of Service, all applicable laws and regulations, and agree that you are responsible for compliance with any applicable local laws. Use and/or access to this site is based on full agreement and compliance of these Terms. All materials contained on this website are protected by applicable copyright and trademark laws.
\n\nThe following terminology applies to these Terms and Conditions, Privacy Statement, Disclaimer Notice, and any or all Agreements:
\n\n“Client”, “Customer”, “You” and “Your” refers to you, the person accessing this website and accepting the Company’s Terms and Conditions;
\n\n“The Company”, “Ourselves”, “We”, “Our” and “Us”, refers to our Company, IntechOpen;
\n\n“Party”, “Parties”, or “Us”, refers to both the Client and ourselves, or either the Client or ourselves.
\n\nAll Terms refer to the offer, acceptance, and consideration of payment necessary to provide assistance to the Client in the most appropriate manner, whether by formal meetings of a fixed duration, or by any other agreed means, for the express purpose of meeting the Client’s needs in respect of provision of the Company’s stated services/products, and in accordance with, and subject to, the prevailing laws of the United Kingdom.
\n\nAny use of the above terminology, or other words in the singular, plural, capitalization and/or he/she or they, are taken as interchangeable.
\n\nUnless otherwise stated, IntechOpen and/or its licensors own the intellectual property rights for all materials on www.intechopen.com. All intellectual property rights are reserved. You may view, download, share, link and print pages from www.intechopen.com for your own personal use, subject to the restrictions set out in these Terms and Conditions.
\n\nWe employ the use of cookies. By using the IntechOpen website you consent to the use of cookies in accordance with IntechOpen’s Privacy Policy. Most modern day interactive websites use cookies to enable the retrieval of user details for each visit. On our site, cookies are predominantly used to enable functionality and ease of use for those visiting the site.
\n\nIn no circumstances shall IntechOpen or its suppliers be liable for any damages (including, without limitation, damages for loss of data or profit, or due to business interruption) arising out of the use, or inability to use, the materials on IntechOpen's websites, even if IntechOpen or an IntechOpen authorized representative has been notified orally or in writing of the possibility of such damage. Some jurisdictions do not allow limitations on implied warranties, or limitations of liability for consequential or incidental damages; consequently, these limitations may not apply to you.
\n\nIntechopen.com website content and services are provided on an "AS IS" and an "AS AVAILABLE" basis. Material appearing on www.intechopen.com could include minor technical, typographical, or photographic errors. IntechOpen may make changes to any material contained on its website at any time without notice.
\n\nIntechOpen has no formal affiliation to any external sites that link to www.intechopen.com, unless otherwise specifically stated. As such, it is not responsible for content that appears on any such sites. The inclusion of any link to IntechOpen does not imply endorsement by IntechOpen. Use of any such linked website is done solely at the user's own discretion.
\n\nWe reserve the right of ownership over our entire website www.intechopen.com, and all contents. By using our services, you agree to remove all links to our website immediately upon request. We also reserve the right to amend these Terms and Conditions and our linking policy at any time. By continuing to link to our website, you agree to be bound to, and abide by, these linking Terms and Conditions.
\n\nIf you find any link on our website, or any linked website, objectionable for any reason, please Contact Us. We will consider all requests to remove links but will have no obligation to do so.
\n\nWithout prior approval and express written permission, you may not create frames around our web pages or use other techniques that alter in any way the visual presentation or appearance of our website.
\n\nIntechOpen may revise its Terms of Service for its website at any time without notice. By using this website, you are agreeing to be bound by the current version of all Terms at the time of use.
\n\nThese Terms and Conditions are governed by and construed in accordance with the laws of the United Kingdom and you irrevocably submit to the exclusive jurisdiction of the courts in London, United Kingdom.
\n\nCroatian version of Terms and Conditions available here
\n'}]},successStories:{items:[]},authorsAndEditors:{filterParams:{sort:"featured,name"},profiles:[{id:"6700",title:"Dr.",name:"Abbass A.",middleName:null,surname:"Hashim",slug:"abbass-a.-hashim",fullName:"Abbass A. Hashim",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/6700/images/1864_n.jpg",biography:"Currently I am carrying out research in several areas of interest, mainly covering work on chemical and bio-sensors, semiconductor thin film device fabrication and characterisation.\nAt the moment I have very strong interest in radiation environmental pollution and bacteriology treatment. The teams of researchers are working very hard to bring novel results in this field. I am also a member of the team in charge for the supervision of Ph.D. students in the fields of development of silicon based planar waveguide sensor devices, study of inelastic electron tunnelling in planar tunnelling nanostructures for sensing applications and development of organotellurium(IV) compounds for semiconductor applications. I am a specialist in data analysis techniques and nanosurface structure. I have served as the editor for many books, been a member of the editorial board in science journals, have published many papers and hold many patents.",institutionString:null,institution:{name:"Sheffield Hallam University",country:{name:"United Kingdom"}}},{id:"54525",title:"Prof.",name:"Abdul Latif",middleName:null,surname:"Ahmad",slug:"abdul-latif-ahmad",fullName:"Abdul Latif Ahmad",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:null},{id:"20567",title:"Prof.",name:"Ado",middleName:null,surname:"Jorio",slug:"ado-jorio",fullName:"Ado Jorio",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:{name:"Universidade Federal de Minas Gerais",country:{name:"Brazil"}}},{id:"47940",title:"Dr.",name:"Alberto",middleName:null,surname:"Mantovani",slug:"alberto-mantovani",fullName:"Alberto Mantovani",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:null},{id:"12392",title:"Mr.",name:"Alex",middleName:null,surname:"Lazinica",slug:"alex-lazinica",fullName:"Alex Lazinica",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/12392/images/7282_n.png",biography:"Alex Lazinica is the founder and CEO of IntechOpen. After obtaining a Master's degree in Mechanical Engineering, he continued his PhD studies in Robotics at the Vienna University of Technology. Here he worked as a robotic researcher with the university's Intelligent Manufacturing Systems Group as well as a guest researcher at various European universities, including the Swiss Federal Institute of Technology Lausanne (EPFL). During this time he published more than 20 scientific papers, gave presentations, served as a reviewer for major robotic journals and conferences and most importantly he co-founded and built the International Journal of Advanced Robotic Systems- world's first Open Access journal in the field of robotics. Starting this journal was a pivotal point in his career, since it was a pathway to founding IntechOpen - Open Access publisher focused on addressing academic researchers needs. Alex is a personification of IntechOpen key values being trusted, open and entrepreneurial. Today his focus is on defining the growth and development strategy for the company.",institutionString:null,institution:{name:"TU Wien",country:{name:"Austria"}}},{id:"19816",title:"Prof.",name:"Alexander",middleName:null,surname:"Kokorin",slug:"alexander-kokorin",fullName:"Alexander Kokorin",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/19816/images/1607_n.jpg",biography:"Alexander I. Kokorin: born: 1947, Moscow; DSc., PhD; Principal Research Fellow (Research Professor) of Department of Kinetics and Catalysis, N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, Moscow.\r\nArea of research interests: physical chemistry of complex-organized molecular and nanosized systems, including polymer-metal complexes; the surface of doped oxide semiconductors. He is an expert in structural, absorptive, catalytic and photocatalytic properties, in structural organization and dynamic features of ionic liquids, in magnetic interactions between paramagnetic centers. The author or co-author of 3 books, over 200 articles and reviews in scientific journals and books. He is an actual member of the International EPR/ESR Society, European Society on Quantum Solar Energy Conversion, Moscow House of Scientists, of the Board of Moscow Physical Society.",institutionString:null,institution:{name:"Semenov Institute of Chemical Physics",country:{name:"Russia"}}},{id:"62389",title:"PhD.",name:"Ali Demir",middleName:null,surname:"Sezer",slug:"ali-demir-sezer",fullName:"Ali Demir Sezer",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/62389/images/3413_n.jpg",biography:"Dr. Ali Demir Sezer has a Ph.D. from Pharmaceutical Biotechnology at the Faculty of Pharmacy, University of Marmara (Turkey). He is the member of many Pharmaceutical Associations and acts as a reviewer of scientific journals and European projects under different research areas such as: drug delivery systems, nanotechnology and pharmaceutical biotechnology. Dr. Sezer is the author of many scientific publications in peer-reviewed journals and poster communications. Focus of his research activity is drug delivery, physico-chemical characterization and biological evaluation of biopolymers micro and nanoparticles as modified drug delivery system, and colloidal drug carriers (liposomes, nanoparticles etc.).",institutionString:null,institution:{name:"Marmara University",country:{name:"Turkey"}}},{id:"61051",title:"Prof.",name:"Andrea",middleName:null,surname:"Natale",slug:"andrea-natale",fullName:"Andrea Natale",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:null},{id:"100762",title:"Prof.",name:"Andrea",middleName:null,surname:"Natale",slug:"andrea-natale",fullName:"Andrea Natale",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:{name:"St David's Medical Center",country:{name:"United States of America"}}},{id:"107416",title:"Dr.",name:"Andrea",middleName:null,surname:"Natale",slug:"andrea-natale",fullName:"Andrea Natale",position:null,profilePictureURL:"//cdnintech.com/web/frontend/www/assets/author.svg",biography:null,institutionString:null,institution:{name:"Texas Cardiac Arrhythmia",country:{name:"United States of America"}}},{id:"64434",title:"Dr.",name:"Angkoon",middleName:null,surname:"Phinyomark",slug:"angkoon-phinyomark",fullName:"Angkoon Phinyomark",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/64434/images/2619_n.jpg",biography:"My name is Angkoon Phinyomark. I received a B.Eng. degree in Computer Engineering with First Class Honors in 2008 from Prince of Songkla University, Songkhla, Thailand, where I received a Ph.D. degree in Electrical Engineering. My research interests are primarily in the area of biomedical signal processing and classification notably EMG (electromyography signal), EOG (electrooculography signal), and EEG (electroencephalography signal), image analysis notably breast cancer analysis and optical coherence tomography, and rehabilitation engineering. I became a student member of IEEE in 2008. During October 2011-March 2012, I had worked at School of Computer Science and Electronic Engineering, University of Essex, Colchester, Essex, United Kingdom. In addition, during a B.Eng. I had been a visiting research student at Faculty of Computer Science, University of Murcia, Murcia, Spain for three months.\n\nI have published over 40 papers during 5 years in refereed journals, books, and conference proceedings in the areas of electro-physiological signals processing and classification, notably EMG and EOG signals, fractal analysis, wavelet analysis, texture analysis, feature extraction and machine learning algorithms, and assistive and rehabilitative devices. I have several computer programming language certificates, i.e. Sun Certified Programmer for the Java 2 Platform 1.4 (SCJP), Microsoft Certified Professional Developer, Web Developer (MCPD), Microsoft Certified Technology Specialist, .NET Framework 2.0 Web (MCTS). I am a Reviewer for several refereed journals and international conferences, such as IEEE Transactions on Biomedical Engineering, IEEE Transactions on Industrial Electronics, Optic Letters, Measurement Science Review, and also a member of the International Advisory Committee for 2012 IEEE Business Engineering and Industrial Applications and 2012 IEEE Symposium on Business, Engineering and Industrial Applications.",institutionString:null,institution:{name:"Joseph Fourier University",country:{name:"France"}}},{id:"55578",title:"Dr.",name:"Antonio",middleName:null,surname:"Jurado-Navas",slug:"antonio-jurado-navas",fullName:"Antonio Jurado-Navas",position:null,profilePictureURL:"https://mts.intechopen.com/storage/users/55578/images/4574_n.png",biography:"Antonio Jurado-Navas received the M.S. degree (2002) and the Ph.D. degree (2009) in Telecommunication Engineering, both from the University of Málaga (Spain). He first worked as a consultant at Vodafone-Spain. From 2004 to 2011, he was a Research Assistant with the Communications Engineering Department at the University of Málaga. In 2011, he became an Assistant Professor in the same department. From 2012 to 2015, he was with Ericsson Spain, where he was working on geo-location\ntools for third generation mobile networks. Since 2015, he is a Marie-Curie fellow at the Denmark Technical University. His current research interests include the areas of mobile communication systems and channel modeling in addition to atmospheric optical communications, adaptive optics and statistics",institutionString:null,institution:{name:"University of Malaga",country:{name:"Spain"}}}],filtersByRegion:[{group:"region",caption:"North America",value:1,count:5703},{group:"region",caption:"Middle and South America",value:2,count:5174},{group:"region",caption:"Africa",value:3,count:1690},{group:"region",caption:"Asia",value:4,count:10246},{group:"region",caption:"Australia and Oceania",value:5,count:889},{group:"region",caption:"Europe",value:6,count:15653}],offset:12,limit:12,total:117317},chapterEmbeded:{data:{}},editorApplication:{success:null,errors:{}},ofsBooks:{filterParams:{topicId:"17"},books:[],filtersByTopic:[{group:"topic",caption:"Agricultural and Biological Sciences",value:5,count:9},{group:"topic",caption:"Biochemistry, Genetics and Molecular Biology",value:6,count:14},{group:"topic",caption:"Business, Management and Economics",value:7,count:2},{group:"topic",caption:"Chemistry",value:8,count:6},{group:"topic",caption:"Computer and Information Science",value:9,count:10},{group:"topic",caption:"Earth and Planetary Sciences",value:10,count:4},{group:"topic",caption:"Engineering",value:11,count:16},{group:"topic",caption:"Environmental Sciences",value:12,count:2},{group:"topic",caption:"Immunology and Microbiology",value:13,count:4},{group:"topic",caption:"Materials Science",value:14,count:5},{group:"topic",caption:"Mathematics",value:15,count:1},{group:"topic",caption:"Medicine",value:16,count:57},{group:"topic",caption:"Neuroscience",value:18,count:1},{group:"topic",caption:"Pharmacology, Toxicology and Pharmaceutical Science",value:19,count:5},{group:"topic",caption:"Physics",value:20,count:2},{group:"topic",caption:"Psychology",value:21,count:3},{group:"topic",caption:"Robotics",value:22,count:1},{group:"topic",caption:"Social Sciences",value:23,count:3},{group:"topic",caption:"Technology",value:24,count:1},{group:"topic",caption:"Veterinary Medicine and Science",value:25,count:2}],offset:12,limit:12,total:0},popularBooks:{featuredBooks:[{type:"book",id:"7802",title:"Modern Slavery and Human Trafficking",subtitle:null,isOpenForSubmission:!1,hash:"587a0b7fb765f31cc98de33c6c07c2e0",slug:"modern-slavery-and-human-trafficking",bookSignature:"Jane Reeves",coverURL:"https://cdn.intechopen.com/books/images_new/7802.jpg",editors:[{id:"211328",title:"Prof.",name:"Jane",middleName:null,surname:"Reeves",slug:"jane-reeves",fullName:"Jane Reeves"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9961",title:"Data Mining",subtitle:"Methods, Applications and Systems",isOpenForSubmission:!1,hash:"ed79fb6364f2caf464079f94a0387146",slug:"data-mining-methods-applications-and-systems",bookSignature:"Derya Birant",coverURL:"https://cdn.intechopen.com/books/images_new/9961.jpg",editors:[{id:"15609",title:"Dr.",name:"Derya",middleName:null,surname:"Birant",slug:"derya-birant",fullName:"Derya Birant"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8545",title:"Animal Reproduction in Veterinary Medicine",subtitle:null,isOpenForSubmission:!1,hash:"13aaddf5fdbbc78387e77a7da2388bf6",slug:"animal-reproduction-in-veterinary-medicine",bookSignature:"Faruk Aral, Rita Payan-Carreira and Miguel Quaresma",coverURL:"https://cdn.intechopen.com/books/images_new/8545.jpg",editors:[{id:"25600",title:"Prof.",name:"Faruk",middleName:null,surname:"Aral",slug:"faruk-aral",fullName:"Faruk Aral"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9157",title:"Neurodegenerative Diseases",subtitle:"Molecular Mechanisms and Current Therapeutic Approaches",isOpenForSubmission:!1,hash:"bc8be577966ef88735677d7e1e92ed28",slug:"neurodegenerative-diseases-molecular-mechanisms-and-current-therapeutic-approaches",bookSignature:"Nagehan Ersoy Tunalı",coverURL:"https://cdn.intechopen.com/books/images_new/9157.jpg",editors:[{id:"82778",title:"Ph.D.",name:"Nagehan",middleName:null,surname:"Ersoy Tunalı",slug:"nagehan-ersoy-tunali",fullName:"Nagehan Ersoy Tunalı"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8686",title:"Direct Torque Control Strategies of Electrical Machines",subtitle:null,isOpenForSubmission:!1,hash:"b6ad22b14db2b8450228545d3d4f6b1a",slug:"direct-torque-control-strategies-of-electrical-machines",bookSignature:"Fatma Ben Salem",coverURL:"https://cdn.intechopen.com/books/images_new/8686.jpg",editors:[{id:"295623",title:"Associate Prof.",name:"Fatma",middleName:null,surname:"Ben Salem",slug:"fatma-ben-salem",fullName:"Fatma Ben Salem"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"7434",title:"Molecular Biotechnology",subtitle:null,isOpenForSubmission:!1,hash:"eceede809920e1ec7ecadd4691ede2ec",slug:"molecular-biotechnology",bookSignature:"Sergey Sedykh",coverURL:"https://cdn.intechopen.com/books/images_new/7434.jpg",editors:[{id:"178316",title:"Ph.D.",name:"Sergey",middleName:null,surname:"Sedykh",slug:"sergey-sedykh",fullName:"Sergey Sedykh"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9208",title:"Welding",subtitle:"Modern Topics",isOpenForSubmission:!1,hash:"7d6be076ccf3a3f8bd2ca52d86d4506b",slug:"welding-modern-topics",bookSignature:"Sadek Crisóstomo Absi Alfaro, Wojciech Borek and Błażej Tomiczek",coverURL:"https://cdn.intechopen.com/books/images_new/9208.jpg",editors:[{id:"65292",title:"Prof.",name:"Sadek Crisostomo Absi",middleName:"C. Absi",surname:"Alfaro",slug:"sadek-crisostomo-absi-alfaro",fullName:"Sadek Crisostomo Absi Alfaro"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"7831",title:"Sustainability in Urban Planning and Design",subtitle:null,isOpenForSubmission:!1,hash:"c924420492c8c2c9751e178d025f4066",slug:"sustainability-in-urban-planning-and-design",bookSignature:"Amjad Almusaed, Asaad Almssad and Linh Truong - Hong",coverURL:"https://cdn.intechopen.com/books/images_new/7831.jpg",editors:[{id:"110471",title:"Dr.",name:"Amjad",middleName:"Zaki",surname:"Almusaed",slug:"amjad-almusaed",fullName:"Amjad Almusaed"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9343",title:"Trace Metals in the Environment",subtitle:"New Approaches and Recent Advances",isOpenForSubmission:!1,hash:"ae07e345bc2ce1ebbda9f70c5cd12141",slug:"trace-metals-in-the-environment-new-approaches-and-recent-advances",bookSignature:"Mario Alfonso Murillo-Tovar, Hugo Saldarriaga-Noreña and Agnieszka Saeid",coverURL:"https://cdn.intechopen.com/books/images_new/9343.jpg",editors:[{id:"255959",title:"Dr.",name:"Mario Alfonso",middleName:null,surname:"Murillo-Tovar",slug:"mario-alfonso-murillo-tovar",fullName:"Mario Alfonso Murillo-Tovar"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9139",title:"Topics in Primary Care Medicine",subtitle:null,isOpenForSubmission:!1,hash:"ea774a4d4c1179da92a782e0ae9cde92",slug:"topics-in-primary-care-medicine",bookSignature:"Thomas F. Heston",coverURL:"https://cdn.intechopen.com/books/images_new/9139.jpg",editors:[{id:"217926",title:"Dr.",name:"Thomas F.",middleName:null,surname:"Heston",slug:"thomas-f.-heston",fullName:"Thomas F. Heston"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9839",title:"Outdoor Recreation",subtitle:"Physiological and Psychological Effects on Health",isOpenForSubmission:!1,hash:"5f5a0d64267e32567daffa5b0c6a6972",slug:"outdoor-recreation-physiological-and-psychological-effects-on-health",bookSignature:"Hilde G. Nielsen",coverURL:"https://cdn.intechopen.com/books/images_new/9839.jpg",editors:[{id:"158692",title:"Ph.D.",name:"Hilde G.",middleName:null,surname:"Nielsen",slug:"hilde-g.-nielsen",fullName:"Hilde G. Nielsen"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8697",title:"Virtual Reality and Its Application in Education",subtitle:null,isOpenForSubmission:!1,hash:"ee01b5e387ba0062c6b0d1e9227bda05",slug:"virtual-reality-and-its-application-in-education",bookSignature:"Dragan Cvetković",coverURL:"https://cdn.intechopen.com/books/images_new/8697.jpg",editors:[{id:"101330",title:"Dr.",name:"Dragan",middleName:"Mladen",surname:"Cvetković",slug:"dragan-cvetkovic",fullName:"Dragan Cvetković"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}}],offset:12,limit:12,total:5146},hotBookTopics:{hotBooks:[],offset:0,limit:12,total:null},publish:{},publishingProposal:{success:null,errors:{}},books:{featuredBooks:[{type:"book",id:"7802",title:"Modern Slavery and Human Trafficking",subtitle:null,isOpenForSubmission:!1,hash:"587a0b7fb765f31cc98de33c6c07c2e0",slug:"modern-slavery-and-human-trafficking",bookSignature:"Jane Reeves",coverURL:"https://cdn.intechopen.com/books/images_new/7802.jpg",editors:[{id:"211328",title:"Prof.",name:"Jane",middleName:null,surname:"Reeves",slug:"jane-reeves",fullName:"Jane Reeves"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9961",title:"Data Mining",subtitle:"Methods, Applications and Systems",isOpenForSubmission:!1,hash:"ed79fb6364f2caf464079f94a0387146",slug:"data-mining-methods-applications-and-systems",bookSignature:"Derya Birant",coverURL:"https://cdn.intechopen.com/books/images_new/9961.jpg",editors:[{id:"15609",title:"Dr.",name:"Derya",middleName:null,surname:"Birant",slug:"derya-birant",fullName:"Derya Birant"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8545",title:"Animal Reproduction in Veterinary Medicine",subtitle:null,isOpenForSubmission:!1,hash:"13aaddf5fdbbc78387e77a7da2388bf6",slug:"animal-reproduction-in-veterinary-medicine",bookSignature:"Faruk Aral, Rita Payan-Carreira and Miguel Quaresma",coverURL:"https://cdn.intechopen.com/books/images_new/8545.jpg",editors:[{id:"25600",title:"Prof.",name:"Faruk",middleName:null,surname:"Aral",slug:"faruk-aral",fullName:"Faruk Aral"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9157",title:"Neurodegenerative Diseases",subtitle:"Molecular Mechanisms and Current Therapeutic Approaches",isOpenForSubmission:!1,hash:"bc8be577966ef88735677d7e1e92ed28",slug:"neurodegenerative-diseases-molecular-mechanisms-and-current-therapeutic-approaches",bookSignature:"Nagehan Ersoy Tunalı",coverURL:"https://cdn.intechopen.com/books/images_new/9157.jpg",editors:[{id:"82778",title:"Ph.D.",name:"Nagehan",middleName:null,surname:"Ersoy Tunalı",slug:"nagehan-ersoy-tunali",fullName:"Nagehan Ersoy Tunalı"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"8686",title:"Direct Torque Control Strategies of Electrical Machines",subtitle:null,isOpenForSubmission:!1,hash:"b6ad22b14db2b8450228545d3d4f6b1a",slug:"direct-torque-control-strategies-of-electrical-machines",bookSignature:"Fatma Ben Salem",coverURL:"https://cdn.intechopen.com/books/images_new/8686.jpg",editors:[{id:"295623",title:"Associate Prof.",name:"Fatma",middleName:null,surname:"Ben Salem",slug:"fatma-ben-salem",fullName:"Fatma Ben Salem"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"7434",title:"Molecular Biotechnology",subtitle:null,isOpenForSubmission:!1,hash:"eceede809920e1ec7ecadd4691ede2ec",slug:"molecular-biotechnology",bookSignature:"Sergey Sedykh",coverURL:"https://cdn.intechopen.com/books/images_new/7434.jpg",editors:[{id:"178316",title:"Ph.D.",name:"Sergey",middleName:null,surname:"Sedykh",slug:"sergey-sedykh",fullName:"Sergey Sedykh"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9208",title:"Welding",subtitle:"Modern Topics",isOpenForSubmission:!1,hash:"7d6be076ccf3a3f8bd2ca52d86d4506b",slug:"welding-modern-topics",bookSignature:"Sadek Crisóstomo Absi Alfaro, Wojciech Borek and Błażej Tomiczek",coverURL:"https://cdn.intechopen.com/books/images_new/9208.jpg",editors:[{id:"65292",title:"Prof.",name:"Sadek Crisostomo Absi",middleName:"C. Absi",surname:"Alfaro",slug:"sadek-crisostomo-absi-alfaro",fullName:"Sadek Crisostomo Absi Alfaro"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"7831",title:"Sustainability in Urban Planning and Design",subtitle:null,isOpenForSubmission:!1,hash:"c924420492c8c2c9751e178d025f4066",slug:"sustainability-in-urban-planning-and-design",bookSignature:"Amjad Almusaed, Asaad Almssad and Linh Truong - Hong",coverURL:"https://cdn.intechopen.com/books/images_new/7831.jpg",editors:[{id:"110471",title:"Dr.",name:"Amjad",middleName:"Zaki",surname:"Almusaed",slug:"amjad-almusaed",fullName:"Amjad Almusaed"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9343",title:"Trace Metals in the Environment",subtitle:"New Approaches and Recent Advances",isOpenForSubmission:!1,hash:"ae07e345bc2ce1ebbda9f70c5cd12141",slug:"trace-metals-in-the-environment-new-approaches-and-recent-advances",bookSignature:"Mario Alfonso Murillo-Tovar, Hugo Saldarriaga-Noreña and Agnieszka Saeid",coverURL:"https://cdn.intechopen.com/books/images_new/9343.jpg",editors:[{id:"255959",title:"Dr.",name:"Mario Alfonso",middleName:null,surname:"Murillo-Tovar",slug:"mario-alfonso-murillo-tovar",fullName:"Mario Alfonso Murillo-Tovar"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}},{type:"book",id:"9139",title:"Topics in Primary Care Medicine",subtitle:null,isOpenForSubmission:!1,hash:"ea774a4d4c1179da92a782e0ae9cde92",slug:"topics-in-primary-care-medicine",bookSignature:"Thomas F. Heston",coverURL:"https://cdn.intechopen.com/books/images_new/9139.jpg",editors:[{id:"217926",title:"Dr.",name:"Thomas F.",middleName:null,surname:"Heston",slug:"thomas-f.-heston",fullName:"Thomas F. Heston"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}}],latestBooks:[{type:"book",id:"7434",title:"Molecular Biotechnology",subtitle:null,isOpenForSubmission:!1,hash:"eceede809920e1ec7ecadd4691ede2ec",slug:"molecular-biotechnology",bookSignature:"Sergey Sedykh",coverURL:"https://cdn.intechopen.com/books/images_new/7434.jpg",editedByType:"Edited by",editors:[{id:"178316",title:"Ph.D.",name:"Sergey",middleName:null,surname:"Sedykh",slug:"sergey-sedykh",fullName:"Sergey Sedykh"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8545",title:"Animal Reproduction in Veterinary Medicine",subtitle:null,isOpenForSubmission:!1,hash:"13aaddf5fdbbc78387e77a7da2388bf6",slug:"animal-reproduction-in-veterinary-medicine",bookSignature:"Faruk Aral, Rita Payan-Carreira and Miguel Quaresma",coverURL:"https://cdn.intechopen.com/books/images_new/8545.jpg",editedByType:"Edited by",editors:[{id:"25600",title:"Prof.",name:"Faruk",middleName:null,surname:"Aral",slug:"faruk-aral",fullName:"Faruk Aral"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9569",title:"Methods in Molecular Medicine",subtitle:null,isOpenForSubmission:!1,hash:"691d3f3c4ac25a8093414e9b270d2843",slug:"methods-in-molecular-medicine",bookSignature:"Yusuf Tutar",coverURL:"https://cdn.intechopen.com/books/images_new/9569.jpg",editedByType:"Edited by",editors:[{id:"158492",title:"Prof.",name:"Yusuf",middleName:null,surname:"Tutar",slug:"yusuf-tutar",fullName:"Yusuf Tutar"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9839",title:"Outdoor Recreation",subtitle:"Physiological and Psychological Effects on Health",isOpenForSubmission:!1,hash:"5f5a0d64267e32567daffa5b0c6a6972",slug:"outdoor-recreation-physiological-and-psychological-effects-on-health",bookSignature:"Hilde G. Nielsen",coverURL:"https://cdn.intechopen.com/books/images_new/9839.jpg",editedByType:"Edited by",editors:[{id:"158692",title:"Ph.D.",name:"Hilde G.",middleName:null,surname:"Nielsen",slug:"hilde-g.-nielsen",fullName:"Hilde G. Nielsen"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"7802",title:"Modern Slavery and Human Trafficking",subtitle:null,isOpenForSubmission:!1,hash:"587a0b7fb765f31cc98de33c6c07c2e0",slug:"modern-slavery-and-human-trafficking",bookSignature:"Jane Reeves",coverURL:"https://cdn.intechopen.com/books/images_new/7802.jpg",editedByType:"Edited by",editors:[{id:"211328",title:"Prof.",name:"Jane",middleName:null,surname:"Reeves",slug:"jane-reeves",fullName:"Jane Reeves"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8063",title:"Food Security in Africa",subtitle:null,isOpenForSubmission:!1,hash:"8cbf3d662b104d19db2efc9d59249efc",slug:"food-security-in-africa",bookSignature:"Barakat Mahmoud",coverURL:"https://cdn.intechopen.com/books/images_new/8063.jpg",editedByType:"Edited by",editors:[{id:"92016",title:"Dr.",name:"Barakat",middleName:null,surname:"Mahmoud",slug:"barakat-mahmoud",fullName:"Barakat Mahmoud"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"10118",title:"Plant Stress Physiology",subtitle:null,isOpenForSubmission:!1,hash:"c68b09d2d2634fc719ae3b9a64a27839",slug:"plant-stress-physiology",bookSignature:"Akbar Hossain",coverURL:"https://cdn.intechopen.com/books/images_new/10118.jpg",editedByType:"Edited by",editors:[{id:"280755",title:"Dr.",name:"Akbar",middleName:null,surname:"Hossain",slug:"akbar-hossain",fullName:"Akbar Hossain"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9157",title:"Neurodegenerative Diseases",subtitle:"Molecular Mechanisms and Current Therapeutic Approaches",isOpenForSubmission:!1,hash:"bc8be577966ef88735677d7e1e92ed28",slug:"neurodegenerative-diseases-molecular-mechanisms-and-current-therapeutic-approaches",bookSignature:"Nagehan Ersoy Tunalı",coverURL:"https://cdn.intechopen.com/books/images_new/9157.jpg",editedByType:"Edited by",editors:[{id:"82778",title:"Ph.D.",name:"Nagehan",middleName:null,surname:"Ersoy Tunalı",slug:"nagehan-ersoy-tunali",fullName:"Nagehan Ersoy Tunalı"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9961",title:"Data Mining",subtitle:"Methods, Applications and Systems",isOpenForSubmission:!1,hash:"ed79fb6364f2caf464079f94a0387146",slug:"data-mining-methods-applications-and-systems",bookSignature:"Derya Birant",coverURL:"https://cdn.intechopen.com/books/images_new/9961.jpg",editedByType:"Edited by",editors:[{id:"15609",title:"Dr.",name:"Derya",middleName:null,surname:"Birant",slug:"derya-birant",fullName:"Derya Birant"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8686",title:"Direct Torque Control Strategies of Electrical Machines",subtitle:null,isOpenForSubmission:!1,hash:"b6ad22b14db2b8450228545d3d4f6b1a",slug:"direct-torque-control-strategies-of-electrical-machines",bookSignature:"Fatma Ben Salem",coverURL:"https://cdn.intechopen.com/books/images_new/8686.jpg",editedByType:"Edited by",editors:[{id:"295623",title:"Associate Prof.",name:"Fatma",middleName:null,surname:"Ben Salem",slug:"fatma-ben-salem",fullName:"Fatma Ben Salem"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}}]},subject:{topic:{id:"21",title:"Psychology",slug:"psychology",parent:{title:"Social Sciences and Humanities",slug:"social-sciences-and-humanities"},numberOfBooks:23,numberOfAuthorsAndEditors:384,numberOfWosCitations:135,numberOfCrossrefCitations:128,numberOfDimensionsCitations:297,videoUrl:null,fallbackUrl:null,description:null},booksByTopicFilter:{topicSlug:"psychology",sort:"-publishedDate",limit:12,offset:0},booksByTopicCollection:[{type:"book",id:"9050",title:"Hypnotherapy and Hypnosis",subtitle:null,isOpenForSubmission:!1,hash:"f5686a1d5917736fa774b2f46e7da8a5",slug:"hypnotherapy-and-hypnosis",bookSignature:"Cengiz Mordeniz",coverURL:"https://cdn.intechopen.com/books/images_new/9050.jpg",editedByType:"Edited by",editors:[{id:"214664",title:"Associate Prof.",name:"Cengiz",middleName:null,surname:"Mordeniz",slug:"cengiz-mordeniz",fullName:"Cengiz Mordeniz"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"7507",title:"Empathy Study",subtitle:null,isOpenForSubmission:!1,hash:"e8318dbbb1e524384596da018870651f",slug:"empathy-study",bookSignature:"Makiko Kondo and Bala Nikku",coverURL:"https://cdn.intechopen.com/books/images_new/7507.jpg",editedByType:"Edited by",editors:[{id:"188019",title:"Dr.",name:"Makiko",middleName:null,surname:"Kondo",slug:"makiko-kondo",fullName:"Makiko Kondo"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9033",title:"Career Development and Job Satisfaction",subtitle:null,isOpenForSubmission:!1,hash:"8cbf79d466559c37f4ec1bcbe6f908f5",slug:"career-development-and-job-satisfaction",bookSignature:"Josiane Fahed-Sreih",coverURL:"https://cdn.intechopen.com/books/images_new/9033.jpg",editedByType:"Edited by",editors:[{id:"103784",title:"Dr.",name:"Josiane",middleName:null,surname:"Fahed-Sreih",slug:"josiane-fahed-sreih",fullName:"Josiane Fahed-Sreih"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"9136",title:"Counseling and Therapy",subtitle:null,isOpenForSubmission:!1,hash:"499608b1cf8111827e1a271e5555a6a6",slug:"counseling-and-therapy",bookSignature:"Simon George Taukeni",coverURL:"https://cdn.intechopen.com/books/images_new/9136.jpg",editedByType:"Edited by",editors:[{id:"202046",title:"Dr.",name:"Simon George",middleName:null,surname:"Taukeni",slug:"simon-george-taukeni",fullName:"Simon George Taukeni"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"7927",title:"Selected Topics in Child and Adolescent Mental Health",subtitle:null,isOpenForSubmission:!1,hash:"d0afa3f41927509c4a21502c591726b8",slug:"selected-topics-in-child-and-adolescent-mental-health",bookSignature:"Samuel Stones, Jonathan Glazzard and Maria Rosaria Muzio",coverURL:"https://cdn.intechopen.com/books/images_new/7927.jpg",editedByType:"Edited by",editors:[{id:"309587",title:"Mr.",name:"Samuel",middleName:"Oliver James",surname:"Stones",slug:"samuel-stones",fullName:"Samuel Stones"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"7904",title:"Aging",subtitle:"Life Span and Life Expectancy",isOpenForSubmission:!1,hash:"4507619de679dfa85bc6e073d163f3c8",slug:"aging-life-span-and-life-expectancy",bookSignature:"Robert J. Reynolds and Steven M. Day",coverURL:"https://cdn.intechopen.com/books/images_new/7904.jpg",editedByType:"Edited by",editors:[{id:"220737",title:"Dr.",name:"Robert",middleName:null,surname:"J. Reynolds",slug:"robert-j.-reynolds",fullName:"Robert J. Reynolds"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"7311",title:"Cognitive and Intermedial Semiotics",subtitle:null,isOpenForSubmission:!1,hash:"2b7d636f6a78bfa31a39bab658a4b18c",slug:"cognitive-and-intermedial-semiotics",bookSignature:"Marta Silvera-Roig and Asunción López-Varela Azcárate",coverURL:"https://cdn.intechopen.com/books/images_new/7311.jpg",editedByType:"Edited by",editors:[{id:"302728",title:"Dr.",name:"Marta",middleName:null,surname:"Silvera-Roig",slug:"marta-silvera-roig",fullName:"Marta Silvera-Roig"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"8864",title:"Family Therapy",subtitle:"New Intervention Programs and Researches",isOpenForSubmission:!1,hash:"e50bb9cef36aeaef4ba976554b3dd141",slug:"family-therapy-new-intervention-programs-and-researches",bookSignature:"Floriana Irtelli",coverURL:"https://cdn.intechopen.com/books/images_new/8864.jpg",editedByType:"Edited by",editors:[{id:"174641",title:"Dr.",name:"Floriana",middleName:null,surname:"Irtelli",slug:"floriana-irtelli",fullName:"Floriana Irtelli"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"6704",title:"Geriatrics Health",subtitle:null,isOpenForSubmission:!1,hash:"7cac7767e0b34391318cd4a680ca0d68",slug:"geriatrics-health",bookSignature:"Hülya Çakmur",coverURL:"https://cdn.intechopen.com/books/images_new/6704.jpg",editedByType:"Edited by",editors:[{id:"190636",title:"Associate Prof.",name:"Hülya",middleName:null,surname:"Çakmur",slug:"hulya-cakmur",fullName:"Hülya Çakmur"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"6593",title:"Decision Making",subtitle:null,isOpenForSubmission:!1,hash:"88cae11440930f7ba788d5cfedec5979",slug:"decision-making",bookSignature:"Fausto Pedro García Márquez, Alberto Pliego Marugán and Mayorkinos Papaelias",coverURL:"https://cdn.intechopen.com/books/images_new/6593.jpg",editedByType:"Edited by",editors:[{id:"22844",title:"Prof.",name:"Fausto Pedro",middleName:null,surname:"García Márquez",slug:"fausto-pedro-garcia-marquez",fullName:"Fausto Pedro García Márquez"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"6381",title:"Gerontology",subtitle:null,isOpenForSubmission:!1,hash:"bf232563c8fe15ef0848ed6ffb8f832d",slug:"gerontology",bookSignature:"Grazia D’Onofrio, Antonio Greco and Daniele Sancarlo",coverURL:"https://cdn.intechopen.com/books/images_new/6381.jpg",editedByType:"Edited by",editors:[{id:"184080",title:"Dr.",name:"Grazia",middleName:null,surname:"D’Onofrio",slug:"grazia-d'onofrio",fullName:"Grazia D’Onofrio"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}},{type:"book",id:"6494",title:"Behavior Analysis",subtitle:null,isOpenForSubmission:!1,hash:"72a81a7163705b2765f9eb0b21dec70e",slug:"behavior-analysis",bookSignature:"Huei-Tse Hou and Carolyn S. Ryan",coverURL:"https://cdn.intechopen.com/books/images_new/6494.jpg",editedByType:"Edited by",editors:[{id:"96493",title:"Prof.",name:"Huei Tse",middleName:null,surname:"Hou",slug:"huei-tse-hou",fullName:"Huei Tse Hou"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter",authoredCaption:"Edited by"}}],booksByTopicTotal:23,mostCitedChapters:[{id:"40977",doi:"10.5772/53885",title:"The Emergence of Scientific Reasoning",slug:"the-emergence-of-scientific-reasoning",totalDownloads:3832,totalCrossrefCites:4,totalDimensionsCites:40,book:{slug:"current-topics-in-children-s-learning-and-cognition",title:"Current Topics in Children's Learning and Cognition",fullTitle:"Current Topics in Children's Learning and Cognition"},signatures:"Bradley J. Morris, Steve Croker, Amy M. Masnick and Corinne Zimmerman",authors:[{id:"154336",title:"Prof.",name:"Bradley",middleName:null,surname:"Morris",slug:"bradley-morris",fullName:"Bradley Morris"},{id:"154337",title:"Prof.",name:"Steve",middleName:null,surname:"Croker",slug:"steve-croker",fullName:"Steve Croker"},{id:"154338",title:"Prof.",name:"Amy",middleName:null,surname:"Masnick",slug:"amy-masnick",fullName:"Amy Masnick"},{id:"154339",title:"Prof.",name:"Corinne",middleName:null,surname:"Zimmerman",slug:"corinne-zimmerman",fullName:"Corinne Zimmerman"}]},{id:"56330",doi:"10.5772/intechopen.69932",title:"Russian Scientific Trends on Specific Language Impairment in Childhood",slug:"russian-scientific-trends-on-specific-language-impairment-in-childhood",totalDownloads:1259,totalCrossrefCites:0,totalDimensionsCites:21,book:{slug:"advances-in-speech-language-pathology",title:"Advances in Speech-language Pathology",fullTitle:"Advances in Speech-language Pathology"},signatures:"Tatiana Tumanova and Tatiana Filicheva",authors:[{id:"204529",title:"Dr.",name:"Tatiana Volodarovna",middleName:null,surname:"Tumanova",slug:"tatiana-volodarovna-tumanova",fullName:"Tatiana Volodarovna Tumanova"},{id:"208704",title:"Dr.",name:"Tatiana Borisovna",middleName:null,surname:"Filicheva",slug:"tatiana-borisovna-filicheva",fullName:"Tatiana Borisovna Filicheva"}]},{id:"36452",doi:"10.5772/38931",title:"Qualitative Research Methods in Psychology",slug:"qualitative-research-methods-in-psychology",totalDownloads:35051,totalCrossrefCites:10,totalDimensionsCites:17,book:{slug:"psychology-selected-papers",title:"Psychology",fullTitle:"Psychology - Selected Papers"},signatures:"Deborah Biggerstaff",authors:[{id:"123274",title:"Dr.",name:"Deborah",middleName:null,surname:"Biggerstaff",slug:"deborah-biggerstaff",fullName:"Deborah Biggerstaff"}]}],mostDownloadedChaptersLast30Days:[{id:"60564",title:"Ageing Process and Physiological Changes",slug:"ageing-process-and-physiological-changes",totalDownloads:4294,totalCrossrefCites:5,totalDimensionsCites:7,book:{slug:"gerontology",title:"Gerontology",fullTitle:"Gerontology"},signatures:"Shilpa Amarya, Kalyani Singh and Manisha Sabharwal",authors:[{id:"226573",title:"Ph.D.",name:"Shilpa",middleName:null,surname:"Amarya",slug:"shilpa-amarya",fullName:"Shilpa Amarya"},{id:"226593",title:"Dr.",name:"Kalyani",middleName:null,surname:"Singh",slug:"kalyani-singh",fullName:"Kalyani Singh"},{id:"243264",title:"Dr.",name:"Manisha",middleName:null,surname:"Sabharwal",slug:"manisha-sabharwal",fullName:"Manisha Sabharwal"}]},{id:"55388",title:"Beauty, Body Image, and the Media",slug:"beauty-body-image-and-the-media",totalDownloads:5738,totalCrossrefCites:2,totalDimensionsCites:5,book:{slug:"perception-of-beauty",title:"Perception of Beauty",fullTitle:"Perception of Beauty"},signatures:"Jennifer S. Mills, Amy Shannon and Jacqueline Hogue",authors:[{id:"202110",title:"Dr.",name:"Jennifer",middleName:null,surname:"Mills",slug:"jennifer-mills",fullName:"Jennifer Mills"}]},{id:"74542",title:"Rolefulness and Interpersonal Relationships",slug:"rolefulness-and-interpersonal-relationships",totalDownloads:113,totalCrossrefCites:0,totalDimensionsCites:0,book:{slug:null,title:"Interpersonal Relationships",fullTitle:"Interpersonal Relationships"},signatures:"Daiki Kato and Mikie Suzuki",authors:null},{id:"73271",title:"Social Media and Its Effects on Beauty",slug:"social-media-and-its-effects-on-beauty",totalDownloads:343,totalCrossrefCites:0,totalDimensionsCites:0,book:{slug:null,title:"Beauty",fullTitle:"Beauty"},signatures:"Mavis Henriques and Debasis Patnaik",authors:null},{id:"68944",title:"Job Training Satisfaction, Job Satisfaction, and Job Performance",slug:"job-training-satisfaction-job-satisfaction-and-job-performance",totalDownloads:1001,totalCrossrefCites:2,totalDimensionsCites:2,book:{slug:"career-development-and-job-satisfaction",title:"Career Development and Job Satisfaction",fullTitle:"Career Development and Job Satisfaction"},signatures:"Wen-Rou Huang",authors:[{id:"305300",title:"Associate Prof.",name:"Wen-Rou",middleName:null,surname:"Huang",slug:"wen-rou-huang",fullName:"Wen-Rou Huang"}]},{id:"68639",title:"Social Media and Young People’s Mental Health",slug:"social-media-and-young-people-s-mental-health",totalDownloads:876,totalCrossrefCites:0,totalDimensionsCites:0,book:{slug:"selected-topics-in-child-and-adolescent-mental-health",title:"Selected Topics in Child and Adolescent Mental Health",fullTitle:"Selected Topics in Child and Adolescent Mental Health"},signatures:"Jonathan Glazzard and Samuel Stones",authors:[{id:"294281",title:"Prof.",name:"Jonathan",middleName:null,surname:"Glazzard",slug:"jonathan-glazzard",fullName:"Jonathan Glazzard"},{id:"309587",title:"Mr.",name:"Samuel",middleName:"Oliver James",surname:"Stones",slug:"samuel-stones",fullName:"Samuel Stones"}]},{id:"74548",title:"The Significance of Family-of-Origin Dynamics for Adults’ Health and Psychological Wellbeing: The Perspective of Bowen Family System Theory",slug:"the-significance-of-family-of-origin-dynamics-for-adults-health-and-psychological-wellbeing-the-pers",totalDownloads:87,totalCrossrefCites:0,totalDimensionsCites:0,book:{slug:null,title:"Interpersonal Relationships",fullTitle:"Interpersonal Relationships"},signatures:"Viktorija Cepukiene",authors:null},{id:"59913",title:"Decision-Making in Complex Dynamic and Evolutive Systems: The Need for a New Paradigm",slug:"decision-making-in-complex-dynamic-and-evolutive-systems-the-need-for-a-new-paradigm",totalDownloads:686,totalCrossrefCites:0,totalDimensionsCites:0,book:{slug:"decision-making",title:"Decision Making",fullTitle:"Decision Making"},signatures:"Bernard Cadet",authors:[{id:"232726",title:"Emeritus Prof.",name:"Bernard",middleName:null,surname:"Cadet",slug:"bernard-cadet",fullName:"Bernard Cadet"}]},{id:"56581",title:"Reading Disorders and the Role of Speech-Language Pathologists",slug:"reading-disorders-and-the-role-of-speech-language-pathologists",totalDownloads:1420,totalCrossrefCites:0,totalDimensionsCites:1,book:{slug:"advances-in-speech-language-pathology",title:"Advances in Speech-language Pathology",fullTitle:"Advances in Speech-language Pathology"},signatures:"Ana Luiza Navas, Tais Ciboto and Juliana Postigo Amorina Borges",authors:[{id:"203355",title:"Ph.D.",name:"Ana Luiza",middleName:null,surname:"Navas",slug:"ana-luiza-navas",fullName:"Ana Luiza Navas"},{id:"211298",title:"MSc.",name:"Tais",middleName:null,surname:"Ciboto",slug:"tais-ciboto",fullName:"Tais Ciboto"},{id:"211299",title:"MSc.",name:"Juliana",middleName:null,surname:"P.A. Borges",slug:"juliana-p.a.-borges",fullName:"Juliana P.A. Borges"}]},{id:"74709",title:"Visual-Motor Perception and Handwriting Performance of Students with Mixed Subtype Dyslexia",slug:"visual-motor-perception-and-handwriting-performance-of-students-with-mixed-subtype-dyslexia",totalDownloads:72,totalCrossrefCites:0,totalDimensionsCites:0,book:{slug:null,title:"Dyslexia",fullTitle:"Dyslexia"},signatures:"Simone Aparecida Capellini, Larissa Sellin, Ilaria D’Angelo, Noemi Del Bianco, Catia Giaconi and Giseli Donadon Germano",authors:null}],onlineFirstChaptersFilter:{topicSlug:"psychology",limit:3,offset:0},onlineFirstChaptersCollection:[{id:"74685",title:"Awareness, Groundedness, Embodiment: Intrapersonal Elements in Interpersonal Relationships",slug:"awareness-groundedness-embodiment-intrapersonal-elements-in-interpersonal-relationships",totalDownloads:34,totalDimensionsCites:0,doi:"10.5772/intechopen.95484",book:{title:"Interpersonal Relationships"},signatures:"Emmanuel Villoria Hernani"},{id:"74488",title:"The Changing Concept of Self and Identity in Aging Working Women from Shelter Homes: Case Studies on Rebuilding of Interpersonal Relationships",slug:"the-changing-concept-of-self-and-identity-in-aging-working-women-from-shelter-homes-case-studies-on-",totalDownloads:24,totalDimensionsCites:0,doi:"10.5772/intechopen.95317",book:{title:"Interpersonal Relationships"},signatures:"Nivedita Das"},{id:"74709",title:"Visual-Motor Perception and Handwriting Performance of Students with Mixed Subtype Dyslexia",slug:"visual-motor-perception-and-handwriting-performance-of-students-with-mixed-subtype-dyslexia",totalDownloads:80,totalDimensionsCites:0,doi:"10.5772/intechopen.93626",book:{title:"Dyslexia"},signatures:"Simone Aparecida Capellini, Larissa Sellin, Ilaria D’Angelo, Noemi Del Bianco, Catia Giaconi and Giseli Donadon Germano"}],onlineFirstChaptersTotal:28},preDownload:{success:null,errors:{}},aboutIntechopen:{},privacyPolicy:{},peerReviewing:{},howOpenAccessPublishingWithIntechopenWorks:{},sponsorshipBooks:{sponsorshipBooks:[{type:"book",id:"10176",title:"Microgrids and Local Energy Systems",subtitle:null,isOpenForSubmission:!0,hash:"c32b4a5351a88f263074b0d0ca813a9c",slug:null,bookSignature:"Prof. Nick Jenkins",coverURL:"https://cdn.intechopen.com/books/images_new/10176.jpg",editedByType:null,editors:[{id:"55219",title:"Prof.",name:"Nick",middleName:null,surname:"Jenkins",slug:"nick-jenkins",fullName:"Nick Jenkins"}],equalEditorOne:null,equalEditorTwo:null,equalEditorThree:null,productType:{id:"1",chapterContentType:"chapter"}}],offset:8,limit:8,total:1},route:{name:"profile.detail",path:"/profiles/180732/juan-c-suris-regueiro",hash:"",query:{},params:{id:"180732",slug:"juan-c-suris-regueiro"},fullPath:"/profiles/180732/juan-c-suris-regueiro",meta:{},from:{name:null,path:"/",hash:"",query:{},params:{},fullPath:"/",meta:{}}}},function(){var e;(e=document.currentScript||document.scripts[document.scripts.length-1]).parentNode.removeChild(e)}()