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1.
Artigo em Inglês | MEDLINE | ID: mdl-38684017

RESUMO

High-Ni layered oxide cathodes are promising candidates for lithium-ion batteries due to their high energy density. However, their cycle stability is compromised by the poor mechanical durability of the particle microstructure. In this study, we investigate the impact of the calcination temperature on microstructural changes, including primary particle growth and pore evolution, using LiNi0.88Mn0.08Co0.04O2 (N884), with an emphasis on the critical calcination temperature for polycrystalline and single-crystal designs in high-Ni cathodes. As the calcination temperature increases, the primary particles undergo a rectangular growth pattern while the pore population decreases. Beyond a certain critical temperature (in this case, 850 °C), a sudden increase in primary particle size and a simultaneous rapid reduction in the pore population are observed. This sudden microstructure evolution leads to poor cycle retention in N884. In contrast, single-crystal particles, free of grain boundaries, synthesized at this critical temperature exhibit superior cycle retention, underscoring the significance of microstructural design over crystalline quality for achieving long-term cyclability. Our study sheds light on the interplay between calcination temperature and microstructural evolution, proposing the critical temperature as a key criterion for single-crystal synthesis.

2.
J Neurosurg ; 135(4): 1164-1172, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482646

RESUMO

OBJECTIVE: The insula is a complex anatomical structure. Accessing tumors in the insula remains a challenge due to its anatomical complexity and the high chance of morbidity. The goal of this study was to evaluate the feasibility of an endoscopic transorbital approach (ETOA) to the insular region based on a cadaveric study. METHODS: One cadaveric head was used to study the anatomy of the insula and surrounding vessels. Then, anatomical dissection was performed in 4 human cadaveric heads using a dedicated endoscopic system with the aid of neuronavigation guidance. To assess the extent of resection, CT scanning was performed before and after dissection. The insular region was directly exposed by a classic transcranial approach to check the extent of resection from the side with a classic transcranial approach. RESULTS: The entire procedure consisted of two phases: an extradural orbital phase and an intradural sylvian phase. After eyelid incision, the sphenoid bone and orbital roof were extensively drilled out with exposure of the frontal and temporal dural layers. After making a dural window, the anterior ramus of the sylvian fissure was opened and dissected. The M2 segment of the middle cerebral artery (MCA) was identified and traced posterolaterally. A small corticectomy was performed on the posterior orbital gyrus. Through the window between the lateral lenticulostriate arteries and M2, the cortex and medulla of the insula were resected in an anteroposterior direction without violation of the M2 segment of the MCA or its major branches. When confirmed by pterional craniotomy, the sylvian fissure and the MCA were found to be anatomically preserved. After validation of the feasibility and safety based on a cadaveric study, the ETOA was successfully performed in a patient with a high-grade glioma (WHO grade III) in the right insula. CONCLUSIONS: The transorbital route can be considered a potential option to access tumors located in the insula. Using an ETOA, the MCA and its major branches were identified and preserved while removal was performed along the long axis of the insula. In particular, lesions in the anterior part of the insula are most benefited by this approach. Because this approach was implemented in only one patient, additional discussion and further verification is required.

3.
Genomics Inform ; 19(4): e39, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35172472

RESUMO

Tamoxifen (TAM) is an anticancer drug used to treat estrogen receptor (ER)‒positive breast cancer. However, its ER-independent cytotoxic and antifungal activities have prompted debates on its mechanism of action. To achieve a better understanding of the ER-independent antifungal action mechanisms of TAM, we systematically identified TAM-sensitive genes through microarray screening of the heterozygous gene deletion library in fission yeast (Schizosaccharomyces pombe). Secondary confirmation was followed by a spotting assay, finally yielding 13 TAM-sensitive genes under the drug-induced haploinsufficient condition. For these 13 TAM-sensitive genes, we conducted a comparative analysis of their Gene Ontology (GO) 'biological process' terms identified from other genome-wide screenings of the budding yeast deletion library and the MCF7 breast cancer cell line. Several TAM-sensitive genes overlapped between the yeast strains and MCF7 in GO terms including 'cell cycle' (cdc2, rik1, pas1, and leo1), 'signaling' (sck2, oga1, and cki3), and 'vesicle-mediated transport' (SPCC126.08c, vps54, sec72, and tvp15), suggesting their roles in the ER-independent cytotoxic effects of TAM. We recently reported that the cki3 gene with the 'signaling' GO term was related to the ER-independent antifungal action mechanisms of TAM in yeast. In this study, we report that haploinsufficiency of the essential vps54 gene, which encodes the GARP complex subunit, significantly aggravated TAM sensitivity and led to an enlarged vesicle structure in comparison with the SP286 control strain. These results strongly suggest that the vesicle-mediated transport process might be another action mechanism of the ER-independent antifungal or cytotoxic effects of TAM.

4.
Mol Cells ; 43(10): 880-888, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33115980

RESUMO

Inherited peripheral neuropathy is a heterogeneous group of peripheral neurodegenerative disorders including Charcot-Marie-Tooth disease. Many peripheral neuropathies often accompany impaired axonal construction and function. To study the molecular and cellular basis of axon-defective peripheral neuropathy, we explore the possibility of using Caenorhabditis elegans, a powerful nematode model equipped with a variety of genetics and imaging tools. In search of potential candidates of C. elegans peripheral neuropathy models, we monitored the movement and the body posture patterns of 26 C. elegans strains with disruption of genes associated with various peripheral neuropathies and compiled a database of their phenotypes. Our assay showed that movement features of the worms with mutations in HSPB1, MFN2, DYNC1H1, and KIF1B human homologues are significantly different from the control strain, suggesting they are viable candidates for C. elegans peripheral neuropathy models.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Mutação , Doenças do Sistema Nervoso Periférico/patologia , Animais , Caenorhabditis elegans/genética , Bases de Dados Factuais , Modelos Animais de Doenças , Dineínas/genética , GTP Fosfo-Hidrolases/genética , Proteínas de Choque Térmico/genética , Humanos , Cinesinas/genética , Locomoção , Doenças do Sistema Nervoso Periférico/genética , Doenças do Sistema Nervoso Periférico/fisiopatologia , Fenótipo , Postura
5.
J Otolaryngol Head Neck Surg ; 49(1): 67, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958073

RESUMO

BACKGROUND: Pedicled nasoseptal flap (PNSF) has significantly improved the surgical outcomes of endoscopic endonasal approach (EEAs) by reducing cerebrospinal fluid (CSF) leakage. The purpose of this study is to assess the feasibility of using a PNSF for anterior skull base (ASB) reconstruction and to describe a method to compensate for a short flap based on our results. METHODS: In this cadaveric study, ASB dissection without sphenoidotomy was performed using 10 formalin-fixed and 5 fresh adult cadaver specimens, and the sufficiency of the PNSF to cover the ASB was assessed. After the sphenoidotomy, the length by which the PNSF fell short in providing coverage at the posterior wall of the frontal sinus (CPFS), and the extent of the anterior coverage from the limbus (CL) of the sphenoid bone was measured. RESULTS: Without sphenoidotomy, the mean length of the remaining PNSF after the coverage of the posterior wall of the frontal sinus was 0.67 cm. After sphenoidotomy, the PNSF fell short by a mean length of 2.10 cm, in providing CPFS. The CL was 1.86 cm. Based on these findings, defects resulting from an endoscopic resection of ASB tumors were reconstructed using PNSF without total sphenoidotomy in 3 patients. There were no postoperative CSF leaks or complications. CONCLUSIONS: The use of PNSF for ASB reconstruction may be insufficient to cover the entire ASB defect after removal of large lesions which need total sphenoidotomy. When possible, by leaving some portion of the anterior sphenoid wall for supporting the PNSF, successful ASB reconstruction could be achieved in endoscopic resection of ASB tumors. Additional methods might be needed in some cases of large ASB lesions wherein the anterior sphenoid wall should be removed totally and the ASB defect is too large.


Assuntos
Procedimentos de Cirurgia Plástica/métodos , Neoplasias da Base do Crânio/cirurgia , Base do Crânio/cirurgia , Retalhos Cirúrgicos , Adulto , Cadáver , Vazamento de Líquido Cefalorraquidiano/prevenção & controle , Dissecação , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Pessoa de Meia-Idade , Septo Nasal/transplante , Neuroblastoma/diagnóstico por imagem , Neuroblastoma/cirurgia , Neoplasias Nasais/diagnóstico por imagem , Neoplasias Nasais/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Osso Esfenoide/cirurgia
6.
Acta Neurochir (Wien) ; 162(9): 2119-2128, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32440923

RESUMO

BACKGROUND: We devised a biportal endoscopic transorbital approach (BiETOA) to gain surgical freedom by making a port for the endoscope and investigated the benefits and limitations of BiETOA. METHODS: A cylindrical port was designed and 3-D printed using biocompatible material. The port was inserted through a keyhole between the superolateral side of the orbital rim and the temporal muscle. An endoscope was inserted through the port, and other instruments were inserted through the conventional transorbital route. BiETOA was used to dissect eight cadaveric heads, and the angle of attack and surgical freedom were assessed. RESULTS: The mean maximal angle of attack was significantly different in BiETOA and endoscopic transorbital approach (ETOA) (P < 0.01) but not in BiETOA and ETOA lateral orbital rim (LOR) osteotomy (P = 0.207, P = 0.21). The mean surgical freedom was significantly different in BiETOA and ETOA (P < 0.01) and in BiETOA and ETOA LOR osteotomy (P < 0.01). In the clinical cases, tumors were removed successfully without any complications. CONCLUSIONS: BiETOA provided increased surgical freedom and better visibility of deep target lesion and resulted in good surgical and cosmetic outcomes.


Assuntos
Cirurgia Endoscópica por Orifício Natural/métodos , Órbita/cirurgia , Cadáver , Endoscópios , Humanos , Cirurgia Endoscópica por Orifício Natural/efeitos adversos , Cirurgia Endoscópica por Orifício Natural/instrumentação , Órbita/anatomia & histologia , Complicações Pós-Operatórias/prevenção & controle , Impressão Tridimensional
7.
Acta Neuropathol ; 138(6): 901-912, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31377847

RESUMO

Low-level somatic mutations have been shown to be the major genetic etiology of intractable epilepsy. The extents thereof, however, have yet to be systematically and accurately explored in a large cohort of resected epilepsy brain tissues. Moreover, clinically useful and precise analysis tools for detecting low-level somatic mutations from unmatched formalin-fixed paraffin-embedded (FFPE) brain samples, the most clinically relevant samples, are still lacking. In total, 446 tissues samples from 232 intractable epilepsy patients with various brain pathologies were analyzed using deep sequencing (average read depth, 1112x) of known epilepsy-related genes (up to 28 genes) followed by confirmatory site-specific amplicon sequencing. Pathogenic mutations were discovered in 31.9% (74 of 232) of the resected epilepsy brain tissues and were recurrently found in only eight major focal epilepsy genes, including AKT3, DEPDC5, MTOR, PIK3CA, TSC1, TSC2, SCL35A2, and BRAF. Somatic mutations, two-hit mutations, and germline mutations accounted for 22.0% (51), 0.9% (2), and 9.1% (21) of the patients with intractable epilepsy, respectively. The majority of pathogenic somatic mutations (62.3%, 33 of 53) had a low variant allelic frequency of less than 5%. The use of deep sequencing replicates in the eight major focal epilepsy genes robustly increased PPVs to 50-100% and sensitivities to 71-100%. In an independent FCDII cohort of only unmatched FFPE brain tissues, deep sequencing replicates in the eight major focal epilepsy genes identified pathogenic somatic mutations in 33.3% (5 of 15) of FCDII individuals (similar to the genetic detecting rate in the entire FCDII cohort) without any false-positive calls. Deep sequencing replicates of major focal epilepsy genes in unmatched FFPE brain tissues can be used to accurately and efficiently detect low-level somatic mutations, thereby improving overall patient care by enriching genetic counseling and informing treatment decisions.


Assuntos
Encéfalo , Epilepsia Resistente a Medicamentos/genética , Mutação , Análise de Sequência/métodos , Adolescente , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/cirurgia , Criança , Pré-Escolar , Estudos de Coortes , Epilepsia Resistente a Medicamentos/metabolismo , Epilepsia Resistente a Medicamentos/patologia , Epilepsia Resistente a Medicamentos/cirurgia , Feminino , Humanos , Lactente , Masculino , Adulto Jovem
8.
Adv Sci (Weinh) ; 5(12): 1801632, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30581721

RESUMO

The development of high-performance oxygen evolution reaction (OER) catalysts is crucial to achieve the clean production of hydrogen via water splitting. Recently, Co-based oxides have been intensively investigated as some of the most efficient and cost-effective OER catalysts. In particular, compositional tuning of Co-based oxides via doping or substitution is shown to significantly affect their catalytic activity. Nevertheless, the origin of this enhanced catalytic activity and the reaction mechanism occurring at catalytic active sites remain controversial. Theoretical investigations are performed on the electrocatalytic properties of pristine and transition metal (Fe, Ni, and Mn)-substituted Co oxides using first-principle calculations. A comprehensive evaluation of the doping effects is conducted by considering various oxygen local environments in the crystal structure, which helps elucidate the mechanism behind the doping-induced enhancement of Co-based catalysts. It is demonstrated that the local distortion induced by dopant cations remarkably facilitates the catalysis at a specific site by modulating the hydrogen bonding. In particular, the presence of Jahn-Teller-active Fe(IV) is shown to result in a substantial reduction in the overpotential at the initially inactive catalysis site without compromising the activity of the pristine active sites, supporting previous experimental observations of exceptional OER performance for Fe-containing Co oxides.

9.
J Epilepsy Res ; 8(1): 1-5, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30090755

RESUMO

Hemispherectomy constitutes an established surgical method in the management of patients with medically intractable epilepsy secondary to severe unilateral hemisphere damage. As opposed to focal resections, in hemispherotomies, the entire hemisphere is disconnected from the remaining nervous system, including the functional regions and fibers. Despite this, hemispherotomy is recommended for certain indications, and has good functional and epilepsy outcomes. Here we describe the indications, epilepsy outcomes, and surgical techniques for several hemispheric surgeries.

10.
Materials (Basel) ; 11(7)2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29976901

RESUMO

In bulk heterojunction polymer solar cells (BHJ-PSCs), poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate) (PEDOT:PSS) is the most commonly used hole selective interlayer (HSIL). However, its acidity, hygroscopic nature, and the use of indium tin oxide (ITO) etching can degrade the overall photovoltaic performance and the air-stability of BHJ-PSCs. Solvent engineering is considered as a facile approach to overcome these issues. In this work, we engineered the HSIL using ethanol (ET) treated PEDOT:PSS to simultaneously enhance the photovoltaic performance properties and air-stability of the fabricated devices. We systematically investigated the influence of ET on the microstructural, morphological, interfacial characteristics of modified HSIL and photovoltaic characteristics of BHJ-PSCs. Compared with the BHJ-PSC with pristine PEDOT:PSS, a significant enhancement of power conversion efficiency (~17%) was witnessed for the BHJ-PSC with PEDOT:PSS-ET (v/v, 1:0.5). Consequently, the BHJ-PSC with PEDOT:PSS-ET (v/v, 1:0.5) as HSIL exhibited remarkably improved air-stability.

11.
Childs Nerv Syst ; 34(6): 1199-1206, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29679197

RESUMO

PURPOSE: Moyamoya disease (MMD) commonly leads to neurocognitive impairment. This study was carried out to show that temporal encephaloduroarteriosynangiosis (EDAS) has a positive neuropsychological impact on pediatric MMD patients. METHODS: Fifty-five participants diagnosed with MMD from 2008 to 2014 were included in this retrospective study. The mean age at the preoperative evaluation was 9.5 years and the mean age at postoperative evaluation was 10.4. The average interval of initial and follow-up test was 10 months. K-WISC-III, Rey-Kim memory test, Children's Color Trails test (CCTT), Wisconsin Card Sorting Test (WCST), and Advanced Test of Attention (ATA) were used to evaluate patient's neurocognitive profile. RESULTS: In this study, preoperative and postoperative neuropsychological fields were compared. Prior operation, pediatric MMD patients showed 54.2% deficit of inattention but only around 2.5% deficit in verbal memory recall function. There was a significant increase of performance IQ and PO score component of PIQ improved almost 10 scores after surgery. For memorial function, there was an improvement of approximately 10 scores in MQ after the surgery. This study also showed parietal activation following surgical treatment which enhanced the ability to interpret visual materials, to register and to retrieve visual information. Interestingly, despite the parietal cover surgery, there was a significant improvement of performance on WCST and CCTT measuring the prefrontal executive function. Concerning failure to maintain set, no significant postoperative improvements were made. However, simple and selective visual attention on ATA was significantly improved postoperatively. CONCLUSIONS: The results from neuropsychological field comparison testifies the effectiveness of temporal EDAS in pediatric MMD patients. The surgery not only enhances the blood flow in operative regions, but it also improves the broad cerebral function including frontoparietal domains. Such alteration leads to overall advancement in cognitive function which are impaired due to MMD.


Assuntos
Revascularização Cerebral/métodos , Doença de Moyamoya/psicologia , Doença de Moyamoya/cirurgia , Adolescente , Criança , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estudos Retrospectivos , Resultado do Tratamento
12.
Neurol Neurochir Pol ; 52(1): 29-34, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29103634

RESUMO

Normal pressure hydrocephalus (NPH) is a chronic disorder caused by interrupted CSF absorption or flow. Generally, shunt placement is first option for NPH treatment. Due to complications of ventriculo-peritoneal (VP) shunt placement, endoscopic third ventriculostomy (ETV) can be considered as an alternative treatment option. Here we report the efficacy of ETV especially in old aged patients with normal pressure hydrocephalus. Total 21 old aged patients with communicating hydrocephalus with opening pressure, measured via lumbar puncture, less than 20cm H2O underwent ETV. 15 patients had primary/idiopathic NPH and 6 patients had secondary NPH. All patients were studied with a MRI to observe the flow void at aqueduct and the fourth ventricle outflow. And all of them underwent ETV. In a group with peak velocity was higher than 5cm/s, nine patients (75%) were evaluated was 'favorable' and three of them (25%) was scored 'poor'. In another group with peak velocity less than 5cm/s, three of them were scored 'poor' and two of them were scored 'stable'. None of them was evaluated as 'favorable'. We also evaluated the outcomes according to etiology: 12 patients (80% of the patients with primary NPH) were evaluated with 'favorable' after ETV treatment. Two patients (13.3%) were as 'stable'. And one patient was as 'poor' evaluated. Five patients (83.3%) among patients with secondary NPH were as 'poor' evaluated and one of them was stable and no patient was as 'favorable' evaluated. 4 patients, which was as 'poor' evaluated in the group with the secondary NPH, underwent additional VP shunt implantation. Overall, the outcomes of the group with the idiopathic NPH after ETV treatment were more favorable than of the group with the secondary NPH. Our study suggest that ETV can be effective for selected elderly patients with primary/idiopathic NPH, when they satisfy criteria including positive aqueduct flow void on T2 Sagittal MRI and the aqueductal peak velocity, which is greater than 5cm/s on cine MRI.


Assuntos
Hidrocefalia de Pressão Normal , Hidrocefalia , Neuroendoscopia , Terceiro Ventrículo , Ventrículos Cerebrais , Humanos , Resultado do Tratamento , Derivação Ventriculoperitoneal , Ventriculostomia
13.
J Neurosurg ; 129(2): 480-489, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29076784

RESUMO

OBJECTIVE For patients with moyamoya disease (MMD), surgical intervention is usually required because of progressive occlusion of the internal carotid artery. The indirect bypass method has been widely accepted as the treatment of choice in pediatric patients. However, in adult patients with MMD, the most effective treatment method remains a matter of debate. Here, the authors compared the clinical outcomes from MMD patients treated with either extracranial-intracranial arterial bypass (EIAB; 43 hemispheres) or modified encephaloduroarteriosynangiosis (mEDAS; 75 hemispheres) to investigate whether mEDAS is an effective surgical method for treating adults with symptomatic MMD. METHODS A comparative analysis was performed in patients treated using either mEDAS or EIAB. Collateral grading, collateral vein counting, and symptom analysis were used to assess the outcome of surgery. RESULTS Seventy-seven percent (58/75) of mEDAS cases and 83.7% (36/43) of EIAB cases in the analysis experienced improvement in their symptoms after surgery. Furthermore, patients in 98.7% (74/75) of mEDAS cases and those in 95.3% (41/43) of EIAB cases exhibited improved collateral grades. Increases in regions of perfusion were seen after both procedures. CONCLUSIONS Modified EDAS and EIAB both result in positive outcomes for symptomatic adults with MMD. However, when considering the benefit of both surgeries, the authors propose mEDAS, a simpler and less strenuous surgery with a lower risk of complications, as a sufficient and safe treatment option for symptomatic adults with MMD.


Assuntos
Revascularização Cerebral/métodos , Doença de Moyamoya/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
14.
ChemSusChem ; 10(12): 2660-2667, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28489333

RESUMO

Given that the highest certified conversion efficiency of the organic-inorganic perovskite solar cell (PSC) already exceeds 22 %, which is even higher than that of the polycrystalline silicon solar cell, the significance of new scalable processes that can be utilized for preparing large-area devices and their commercialization is rapidly increasing. From this perspective, the electrodeposition method is one of the most suitable processes for preparing large-area devices because it is an already commercialized process with proven controllability and scalability. Here, a highly uniform NiOx layer prepared by electrochemical deposition is reported as an efficient hole-extraction layer of a p-i-n-type planar PSC with a large active area of >1 cm2 . It is demonstrated that the increased surface roughness of the NiOx layer, achieved by controlling the deposition current density, facilitates the hole extraction at the interface between perovskite and NiOx , and thus increases the fill factor and the conversion efficiency. The electrochemically deposited NiOx layer also exhibits extremely uniform thickness and morphology, leading to highly efficient and uniform large-area PSCs. As a result, the p-i-n-type planar PSC with an area of 1.084 cm2 exhibits a stable conversion efficiency of 17.0 % (19.2 % for 0.1 cm2 ) without showing hysteresis effects.


Assuntos
Compostos de Cálcio/química , Fontes de Energia Elétrica , Níquel/química , Óxidos/química , Energia Solar , Titânio/química , Eletroquímica
16.
Adv Mater ; 29(21)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28370464

RESUMO

The development of a high-performance oxygen evolution reaction (OER) catalyst is pivotal for the practical realization of a water-splitting system. Although an extensive search for OER catalysts has been performed in the past decades, cost-effective catalysts remain elusive. Herein, an amorphous cobalt phyllosilicate (ACP) with layered crystalline motif prepared by a room-temperature precipitation is introduced as a new OER catalyst; this material exhibits a remarkably low overpotential (η ≈ 367 mV for a current density of 10 mA cm-2 ). A structural investigation using X-ray absorption spectroscopy reveals that the amorphous structure contains layered motifs similar to the structure of CoOOH, which is demonstrated to be responsible for the OER catalysis based on density functional theory calculations. However, the calculations also reveal that the local environment of the active site in the layered crystalline motif in the ACP is significantly modulated by the silicate, leading to a substantial reduction of η of the OER compared with that of CoOOH. This work proposes amorphous phyllosilicates as a new group of efficient OER catalysts and suggests that tuning of the catalytic activity by introducing redox-inert groups may be a new unexplored avenue for the design of novel high-performance catalysts.

17.
Sensors (Basel) ; 17(4)2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-28406469

RESUMO

In this study, we developed a pore size/pore area-controlled optical biosensor-based anodic aluminum oxide (AAO) nanostructure. As the pore size of AAO increases, the unit cell of AAO increases, which also increases the non-pore area to which the antibody binds. The increase in the number of antibodies immobilized on the surface of the AAO enables effective detection of trace amounts of antigen, because increased antigen-antibody bonding results in a larger surface refractive index change. High sensitivity was thus achieved through amplification of the interference wave of two vertically-incident reflected waves through the localized surface plasmon resonance phenomenon. The sensitivity of the fabricated sensor was evaluated by measuring the change in wavelength with the change in the refractive index of the device surface, and sensitivity was increased with increasing pore-size and non-pore area. The sensitivity of the fabricated sensor was improved and up to 11.8 ag/mL serum amyloid A1 antigen was detected. In addition, the selectivity of the fabricated sensor was confirmed through a reaction with a heterogeneous substance, C-reactive protein antigen. By using hard anodization during fabrication of the AAO, the fabrication time of the device was reduced and the AAO chip was fabricated quickly and easily.


Assuntos
Nanoestruturas , Óxido de Alumínio , Proteína C-Reativa , Eletrodos , Ressonância de Plasmônio de Superfície
18.
Childs Nerv Syst ; 33(5): 767-775, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28332154

RESUMO

INTRODUCTION: The object of this study is to understand abnormal dynamic of cerebrospinal fluid (CSF) in patients with neurofibromatosis type 1 (NF1), which may cause temporal lobe herniation and bulging of temporal fossa. METHODS: Four patients, three females and one male, with NF1 were studied retrospectively. They presented with a similar craniofacial deformity, which consisted of pulsatile exophthalmos, an enlarged bony orbit, dysplasia of the sphenoid wing with the presence of a herniation of the temporal lobe into the orbit, and a bulging temporal fossa. RESULTS AND DISCUSSION: Surgical exploration demonstrated abnormally thickened arachnoid membrane in one case. Protruding temporal lobe, which was one of the main symptoms in NF1 patients, could be stopped by control of intracranial pressure (ICP) via programmable ventriculoperitoneal shunt (VPS) or extra ventricle drainage implantation. The dense fibrosis of the arachnoid membrane and consequent altered hemispheric CSF dynamics may cause symptoms including pulsatile exophthalmos and consequent worsening of vision, prolapse of the temporal lobe, and enlargement of the temporal fossa. This finding may not present with general features of hydrocephalus, so that delays in diagnosis often result. CONCLUSION: For the NF1 patients with cranio-orbito-temporal deformities, prior to any surgical reconstruction, control of increased ICP (IICP) should be primarily considered.


Assuntos
Aracnoide-Máter/diagnóstico por imagem , Pressão do Líquido Cefalorraquidiano/fisiologia , Hidrodinâmica , Neurofibromatose 1/diagnóstico por imagem , Índice de Gravidade de Doença , Lobo Temporal/diagnóstico por imagem , Adolescente , Adulto , Aracnoide-Máter/cirurgia , Criança , Feminino , Humanos , Masculino , Neurofibromatose 1/complicações , Neurofibromatose 1/cirurgia , Estudos Retrospectivos , Lobo Temporal/cirurgia
19.
Sci Rep ; 7: 45079, 2017 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-28338088

RESUMO

Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is most commonly used as an anode buffer layer in bulk-heterojunction (BHJ) polymer solar cells (PSCs). However, its hygroscopic and acidic nature contributes to the insufficient electrical conductivity, air stability and restricted photovoltaic (PV) performance for the fabricated PSCs. In this study, a new multifunctional additive, 2,3-dihydroxypyridine (DOH), has been used in the PEDOT: PSS buffer layer to obtain modified properties for PEDOT: PSS@DOH and achieve high PV performances. The electrical conductivity of PEDOT:PSS@DOH films was markedly improved compared with that of PEDOT:PSS. The PEDOT:PSS@DOH film exhibited excellent optical characteristics, appropriate work function alignment, and good surface properties in BHJ-PSCs. When a poly(3-hexylthiohpene):[6,6]-phenyl C61-butyric acid methyl ester blend system was applied as the photoactive layer, the power conversion efficiency of the resulting PSCs with PEDOT:PSS@DOH(1.0%) reached 3.49%, outperforming pristine PEDOT:PSS, exhibiting a power conversion enhancement of 20%. The device fabricated using PEDOT:PSS@DOH (1.0 wt%) also exhibited improved thermal and air stability. Our results also confirm that DOH, a basic pyridine derivative, facilitates adequate hydrogen bonding interactions with the sulfonic acid groups of PSS, induces the conformational transformation of PEDOT chains and contributes to the phase separation between PEDOT and PSS chains.

20.
J Cerebrovasc Endovasc Neurosurg ; 18(3): 286-290, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27847776

RESUMO

The incidence of intracerebral hemorrhage in those aged 45-84 years is 0.3-0.5%. In people over 80 years of age, this incidence increases 25-fold compared with that of the total population. The most common causes of spontaneous intracerebral hemorrhage in the younger population are vascular malformation, aneurysm, and overuse of drugs. In contrast, common causes in the elderly include hypertension, tumors, and coagulation disorders. Here, we present a case involving a 72-year-old male patient who, without any of these predisposing conditions, was admitted to the hospital with spontaneous intracerebral hemorrhage and showed signs of multifocal intracerebral hemorrhage during his stay. We conclude that spontaneous intracerebral hemorrhage can occur without any predisposing factors, and can lead to a patient's death. Therefore, the possibility of recurrent spontaneous intracerebral hemorrhage must be considered in patients with primary spontaneous intracerebral hemorrhage.

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