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Vacancy in 6H—Silicon carbide Studied by Slow Positron Beam

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chinese Physics Letters 2003年第7期20卷 1105-1108页

作者：王海云翁惠民杭德生周先意叶邦角范扬眉韩荣典 c.c.ling Y.P.Hui DepartmentofModernPhysics universityofScienceandTechnologyofChinaHefei230027 DepartmentofPhysics NanjingUniversitynanjing210093 DepartmentofPhysics TheuniversityofHongKongHongKong

The defect changes in 6H-Sic after annealing and 10MeV electron irradiation have been studied by using a variable-energy positron beam. It was found that after annealing, the defect concentration in n-type 6H-Sic decreased due to recombination with interstitials. When the sample was annealed at 1400°c for 30min in vacuum, a 20-nm thickness Si layer was found on the top of the Sic substrate, this is a direct proof of the Si atoms diffusing to surface when annealed at high temperature stages. After 10MeV electron irradiation, for n-type 6H-Sic, the S parameter increased from 0.4739 to 0.4822, and the relative positron-trapping rate was about 27.878 times of the origin sample, this shows that there are some defects created in n-type 6H-Sic. For p-type 6H-Sic, it is very unclear, this may be because of the opposite charge of vacancy defects.

关键词： Silicon carbide

Al/GaSb contact with Slow Positron Beam

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chinese Journal of chemical Physics 2006年第2期19卷 169-172页

作者：王海云翁惠民 c.c.ling 叶邦角周先意中国科学技术大学近代物理系合肥230026 香港大学物理系

Annealing study of the Al/GaSb system was performed by using a slow positron beam and the measurement of X-ray diffraction. The S parameter against positron energy data were fitted by a three layer model （Al/interface/GaSb）. It was found there was a ～5 nm interfacial at the region between the Al layer and bulk in the sample of as-deposited. After the 400 ℃ annealing, this interfacial region extends to over 40 nm and S parameter dramatically drops. This is possibly due to a new phase formation induced by the atoms＇inter-diffusion at the interface. The annealing out of the open volume defects in the Al layer was revealed by the decrease of the S parameter and the increase of the effective diffusion length of the Al layer. Annealing behaviors of Sb and Lb of the GaSb bulk showed the annealing out of positron traps at 250 ℃. However,further annealing at 400 ℃ induces formation of positron traps, which are possibly another kind of VGarelated defect and the positron shallow trap GaSb anti-site. The results of the X-ray diffraction experiment verified the conclusion of obtained by using positron technology.

关键词： Positron Defect Trapping Al/GaSb Interface

γ射线诱发大鼠胚胎细胞转化与N－ras的激活

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生物化学与生物物理进展 1994年第3期21卷 228-234页

作者：陈昌虎姚开泰 c.c.ling 湖南医科大学肿瘤研究所 Memorial Sloan-Keitering cancer center New YorkN.YI.USA

以γ射线诱发转化的大鼠胚胎细胞（ＲＥＣ：ｍｙｃ：γ３３）的ＤＮＡ构建粘粒基因库，用总基因库ＤＮＡ转染ＮＩＨ／３Ｔ３细胞，产生转化灶的ＤＮＡ作二轮转染，二轮转化的ＮＩＨ／３Ｔ３细胞内有大鼠ＲＥＣ：ｍｙｃ：γ３３ＤＮＡ中... 详细信息

以γ射线诱发转化的大鼠胚胎细胞（ＲＥＣ：ｍｙｃ：γ３３）的ＤＮＡ构建粘粒基因库，用总基因库ＤＮＡ转染ＮＩＨ／３Ｔ３细胞，产生转化灶的ＤＮＡ作二轮转染，二轮转化的ＮＩＨ／３Ｔ３细胞内有大鼠ＲＥＣ：ｍｙｃ：γ３３ＤＮＡ中具转化活性的Ｎ－ｒａｓ基因，用不对称ＰＣＲ和ＤＮＡ序列分析法证明，ＲＥＣ：ｍｙｃ：γ３３细胞中鼠Ｎ－ｒａｓ的活化是由于第６１位密码子的Ａ→Ｇ点突变。ＮＩＨ／３Ｔ３转化灶中鼠Ｎ－ｒａｓ也有同样点突变，但ＮＩＨ／３Ｔ３细胞的内源性Ｎ－ｒａｓ基因则无此突变。

关键词： γ射线鼠胚胎细胞转化 N-ras基因活化

Status and prospects for symmetric organic redox flow batteries

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Journal of Energy chemistry 2025年第1期100卷 125-143页

作者： Md Al Raihan c.Adam Dyker Department of chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORFBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORFBs involve a single bipolar species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

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Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru c.Guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of Medicine–The University of British columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EMBASE,Ovid MEDLINE,Web of Science core collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P Gc-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong Zhang Zhiying chen Yinyi Xiong Qin Zhou ling-Qiang Zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang clinical Precision Medicine Research center JiujiangJiangxi ProvinceChina center for cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGc-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGc-cGMP pathway synaptic dysfunction vascular dementia

Multiple sclerosis is at a checkpoint: advancing the program

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Neural Regeneration Research 2025年第3期20卷 811-812页

作者： Brandon c.Smith Jessica L.Williams Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Biological Geologicaland Environmental SciencesCleveland State UniversityClevelandOHUSA

Multiple sclerosis(MS) is a chronic inflammatory and demyelinating disease of the central nervous system(cNS). Patients with MS experience sensory and motor function loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping Yu Emily choi Michael QJiang ling Wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the ca^(2+)hypothesis of Alzheimer's disease and recent advances,this ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

Boosting charge extraction and efficiency of inverted perovskite solar cells through coordinating group modification at the buffer layer/cathode interface

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Nano Research 2025年第1期18卷 415-423页

作者： Zhiqing Liang Ziqiu Ren Ziyu Wang Nan Yan ling Li Bo Zhang Yanlin Song college of chemistry Zhengzhou UniversityZhengzhou 450052China Key Laboratory of Applied Surface and colloid chemistry Ministry of Education Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing Engineering Research Center of Nanomaterials for Green Printing TechnologyNational Laboratory for Molecular Sciences(BNLMS)Beijing 100190China

In inverted perovskite solar cells (PScs),effective modification of the interface between the metalcathode and electron transport layer (ETL) is crucial forachieving high performance and stability. Herein, sulfonatedbathocuproine, commonly known as disodium bathocuproinedisulfonate (BcDS), was employed as a cathode buffer layerto address the interfacial issues at the [6,6]-phenyl-c61-butyricacid methyl ester (PcBM)/Ag interface. BcDS possesses theability to form coordinate bonds with Ag electrodes. Theutilization of the BcDS buffer layer enhanced the chargeextraction capability at the cathode interface whilesimultaneously achieving interfacial defect passivation,improving interfacial contact and increasing the built-in electricfield. consequently, a power conversion efficiency (PcE) of25.06% was achieved. Furthermore, owing to the excellent filmforminguniformity of BcDS on PcBM, the stability of thedevice was also improved. After storage in dry air for morethan 2000 h, the device maintained 96% of its initial efficiency. This work underscores the remarkable potential of tailoringcoordination groups to enhance charge extraction efficiency at the ETL-cathode interface, unveiling a promising newfrontier in buffer layer development and performance optimization strategies for PScs.

关键词： perovskite solar cells buffer layer bathocuproine disulfonate coordination group modification electron transport layer(ETL)-cathode interface