检索结果-南通市图书馆

Heterogeneity of the Neural Composition of Cortical Regions as a Condition for a Wide Range Regulating Spontaneous Activ.ty

引用

Journal of Behav.oral and Brain Science 2020年第5期10卷 220-236页

作者： Yulia S. Mednikov. anna v. rogal Institute of Higher Nerv.us Activ.ty and Neurophysiology of RAS Moscow Russia

On the slices of sensorimotor and frontal cortex in layer v.of guinea pigs the div.rsity of neuronal spontaneous activ.ty, the mechanism of its origin and functional specificity were studied. In both regions, neurons that did not hav. spontaneous activ.ty predominated (39% in the sensorimotor cortex and 32% in the frontal cortex) ov.r neurons with any other firing lev.ls. The iontophoretic application of the excitatory transmitter, glutamate, caused activ.tion spike reactions in all registered neurons;moreov.r, short-term activ.tion reactions to glutamate had a significantly longer after-discharge in neurons of the frontal cortex (up to 2500 ms and more) compared to reactions of neurons of the sensorimotor region. This means that postexcitatory hyperpolarization in nerv. cells of the frontal cortex is less expressed and, therefore, they hav. a lower density of K+ channels on their membranes. With an increase in the lev.l of spontaneous activ.ty, K+ membrane permeability decreases, which is confirmed by the appearance of a long activ.tion reaction to acetylcholine (which blocks K+ channels), exactly when spontaneous firing appears in “silent” neurons. Despite the fact that spontaneous activ.ty is formed by glutamatergic excitation, its considerable div.rsity is associated with the structural and membrane characteristics of neurons, which determine the different degrees of EPSPs attenuation on the way of mov.ng along dendrites. Acetylcholine regulates this process in different ways, in accordance with different states of K+ membrane permeability. Therefore, the lower content of K+ channels on the membranes of neurons of the frontal cortex does not allow regulating spontaneous activ.ty in the same range as occurs in neurons of the sensorimotor region. The presence of a high proportion of spontaneously inactiv. neurons in the cortex (higher in the sensorimotor cortex) suggests that cortical neurons are generally characterized by a high density of K+ channels and a signi

关键词： Sensorimotor Cortex Frontal Cortex Spontaneous Activ.ty Glutamate Post-Activ.tion Aftereffect Acetylcholine

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Semantic Segmentation of Lumbar v.rtebrae Using Meijering U-Net(MU-Net)on Spine Magnetic Resonance Images

引用

Computer Modeling in Engineering & Sciences 2025年第1期142卷 733-757页

作者： Lakshmi S v.v.Shiloah Elizabeth Darmanayagam Sunil Retmin Raj Cyril Department of Computer Science and Engineering College of Engineering GuindyAnna UniversityChennai600025India Department of Information Technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a detailed v.ew of the soft tissues,including the spinal cord,nerv.s,interv.rtebral discs,and v.rtebrae,Magnetic Resonance Imaging is thought to be the most effectiv. method for imaging the *** semantic segmentation of v.rtebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the v.rtebrae in Magnetic Resonance Images from the surrounding v.riety of tissues,including muscles,ligaments,and interv.rtebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achiev.s high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering conv.lutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar v.rtebrae L1 to L5 and sacral v.rtebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expanded from T1-weighted mid-sagittal MRI images of 515 patients in the Lumbar Spine MRI Dataset publicly av.ilable from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar v.rtebrae giv.s better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DSC),97.36%of Jaccard coefficient,and 92.55%mean Intersection ov.r Union(mean IoU)metrics using the mentioned dataset.

关键词： Computer aided diagnosis(CAD) magnetic resonance imaging(MRI) semantic segmentation lumbar v.rtebrae deep learning U-Net model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Interactiv. effects of metal pollution and ocean acidification on physiology of marine organisms

引用

Current Zoology 2015年第4期61卷 653-668页

作者： anna v. Iv.nina Inna M. Sokolov. Department of Biological Sciences University of North Carolina at Charlotte Charlotte NC 28223 USA

Changes in the global env.ronment such as ocean acidification （OA） may interact with anthropogenic pollutants including trace metals threatening the integrity of marine ecosystems. We analyze recent studies on the interactiv. effects of OA and trace metals on marine organisms with a focus on the physiological basis of these interactions. Our analysis shows that the responses to elev.ted CO2 and metals are strongly dependent on the species, dev.lopmental stage, metal biochemistry and the degree of env.ronmental hypercapnia, and cannot be directly predicted from the CO2-induced changes in metal solubility and speciation. The key physiological functions affected by both the OA and trace metal exposures inv.lv. acid-base regulation, pro- tein turnov.r and mitochondrial bioenergetics, reflecting the sensitiv.ty of the underlying molecular and cellular pathways to CO2 and metals. Physiological interactions between elev.ted CO2 and metals may impact the organisms＇ capacity to maintain ac- id-base homeostasis and reduce the amount of energy av.ilable for fitness-related functions such as growth, dev.lopment and re- production thereby affecting surv.v.l and performance of estuarine populations. Env.ronmental hypercapnia may also affect the marine food webs by altering predator-prey interactions and the trophic transfer of metals in the food chain. Howev.r, our under- standing of the degree to which these effects can impact the function and integrity of marine ecosystems is limited due the scar- city of the published research and its bias towards certain taxonomic groups. Future research priorities should include studies of metal x Pco2 interactions focusing on critical physiological functions （including acid-base, protein and energy homeostasis） in a greater range of ecologically and economically important marine species, as well as including the field populations naturally ex- posed （and potentially adapted） to different lev.ls of metals and CO2 in their env.ronments [Curre

关键词： CO2 Trace metals Metal accumulation Acid-base homeostasis Bioenergetics Estuaries

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular targets of cancer chemoprev.ntion by garlic-deriv.d organosulfides

引用

Acta Pharmacologica Sinica 2007年第9期28卷 1355-1364页

作者： anna HERMAN-ANTOSIEWICZ anna A POWOLNY Shiv.ndra v.SINGH Department of Molecular Biology Univ.rsity of Gda(sk Kladki 2480-822 GdaskPoland Department of Pharmacology and Univ.rsity of Pittsburgh Cancer Institute University of Pittsburgh School of MedicinePittsburghPennsylvania 15213USA

The medicinal benefits of Allium v.getables,especially garlic,hav. been notedthroughout recorded *** known health benefits of Allium v.getablesand their constituents include cardiov.scular protectiv. effects,stimulation ofimmune function,reduction of blood glucose lev.l,radioprotection,improv.mentof memory loss,protection against microbial,v.ral and fungal infections,as well asanticancer ***-based case control studies hav. suggested aninv.rse correlation between dietary intake of Allium v.getables and the risk ofdifferent types of *** anticarcinogenic effect of Allium v.getables in-cluding garlic is attributed to organosulfur compounds (OSC),which are highlyeffectiv. in affording protection against cancer in animal models induced by av.riety of chemical *** recent studies hav. shown that certainnaturally occurring OSC analogues can suppress proliferation of cancer cells inculture and in *** OSC-induced changes in the proliferation of cancer cellsare frequently associated with perturbations in cell cycle progression and induc-tion of G2/M phase *** OSC hav. also been demonstrated to induceapoptosis v.a the intrinsic pathway by altering the ratio of the Bcl-2 family ofproteins both in cell culture and in in v.v. ***-angiogenic activ.ty forgarlic-deriv.d OSC has also been *** article summarizes currentknowledge on molecular targets of cancer chemoprev.ntion by OSC.

关键词： garlic organosulfides apoptosis cell cycle angiogenesis chemoprev.ntion

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nonlinear interference in crystal superlattices

引用

Light(Science & Applications) 2020年第1期9卷 1239-1245页

作者： anna v.Paterov. Leonid A.Kriv.tsky Institute of Materials Research and Engineering(IMRE) Agency for Science Technology and Research(A*STAR)138634 SingaporeSingapore

Nonlinear interferometers with correlated photons hold promise to adv.nce optical characterization and metrology techniques by improv.ng their performance and *** interferometers offer subshot noise phase sensitiv.ty and enable measurements in detection-challenging regions using inexpensiv. and efficient *** sensitiv.ty of nonlinear interferometers,defined by the ability to measure small shifts of interference fringes,can be significantly enhanced by using multiple nonlinear elements,or crystal ***,to date,experiments with more than two nonlinear elements hav. not been realized,thus hindering the potential of nonlinear ***,we build a nonlinear interferometer with up to fiv. nonlinear elements,referred to as superlattices,in a highly stable and v.rsatile *** study the modification of the interference pattern for different configurations of the superlattices and perform a proof-of-concept gas sensing experiment with enhanced *** approach offers a v.able path towards broader adoption of nonlinear interferometers with correlated photons for imaging,interferometry,and spectroscopy.

关键词： spectroscopy nonlinear Nonlinear

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Reducing intrathecal pressure after traumatic spinal cord injury: a potential clinical target to promote tissue surv.v.l

引用

Neural Regeneration Research 2015年第3期10卷 380-382页

作者： anna v.Leonard Robert v.nk School of Medical Sciences University of Adelaide Div.sion of Health Sciences University of South Australia

Spinal cord injury （SCI） is an unexpected ev.nt that is both dev.stating and debilitating, resulting in not just motor and sensory loss, but also autonomic dysfunction of the bladder, bowel and sexual organs. Currently, there are no treatments av.ilable to improv. outcome follow- ing SCI, leav.ng indiv.duals with permanent and lifelong physical disability. Worldwide it is estimated that more than 500,000 people sustain a SCI each year, with av.rage lifetime cost of paraplegia and quadriplegia estimated at $5 million and $9.5 million respectiv.ly. We therefore urgently need effectiv. therapies to improv. quality of life following SCI, and this requires a greater understanding of how cell and axonal injury dev.lops after the traumatic ev.nt.

关键词： ITP TBI a potential clinical target to promote tissue surv.v.l Reducing intrathecal pressure after traumatic spinal cord injury SCI

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Modeling corrosion behav.or of gas tungsten arc welded titanium alloy

引用

中国有色金属学会会刊：英文版 2007年第4期17卷 676-680页

作者： M. Balasubramanian v. Jay abalan v. Balasubramanian Department of Mechanical Engineering Maamallan Institute of Technology Anna University Department of Manufacturing Engineering Anna University Department of Manufacturing Engineering Annamalai University

The pitting corrosion characteristics of pulse TIG welded Ti-6Al-4v.titanium alloy in marine env.ronment were explained. Besides the rapid adv.nce of titanium metallurgy, this is also due to the successful solution of problems associated with the dev.lopment of titanium alloy welding. The preferred welding process of titanium alloy is frequently gas tungsten arc(GTA) welding due to its comparativ.ly easier applicability and better economy. In the case of single pass GTA welding of thinner section of this alloy, the pulsed current has been found beneficial due to its adv.ntages ov.r the conv.ntional continuous current process. The benefit of the process is utilized to obtain better quality titanium weldments. Four factors, fiv. lev.ls, central composite, rotatable design matrix are used to optimize the required number of experiments. The mathematical models hav. been dev.loped by response surface method(RSM). The results rev.al that the titanium alloy can form a protectiv. scale in marine env.ronment and is resistant to pitting corrosion. Experimental results are prov.ded to illustrate the proposed approach.

关键词：钛合金脉冲电流钨电极惰性气体保护焊腐蚀行为

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Indentation fracture toughness of single-crystal Bi2Te3 topological insulators

引用

Nano Research 2016年第4期9卷 1032-1042页

作者： Caterina Lamuta anna Cupolillo Antonio Politano Ziya S. Aliev.Mahammad B. Babanly Ev.ueni v. Chulkov.Leonardo Pagnotta Department of Mechanical Energy and Management Engineering University ofCalabria Ponte P Bucci Cuba 44C 87036 Rende Italy Department of Physics University of Calabria Ponte P Bucci Cuba 31 C 87036 Rende Italy Institute of Catalysis and Inorganic Chemistry ANAS AZ1143 Baku Azerbaijian Institute of Physics ANAS AZ1143 Baku Azerbaijian Donostia International Physics Center (DIPC) Paseo de Manuel Lardizabal 4 20018 San Sebastian/Donostia Spain Departamento de Fisica de Materiales Universidad del Pals Vasco Apartado 1072 20080 San Sebastidn/Donostia Spain Centro de Fisica de Materiales CFM-Materials Physics Center MPC Centro Mixto CSIC-UPV/EHU Paseo de Manuel Lardizabal 5 20018 San Sebastion/Donostia Spain Saint Petersburg State Univ.rsity 198504 Saint Petersburg Russian Federation Tomsk State Univ.rsity 634050 Tomsk Russian Federation

Bismuth teUuride （Bi2Te3） is one of the most important commercial thermoelectric materials. In recent years, the discov.ry of topologically protected surface states in Bi chalcogenides has pav.d the way for their application in nanoelectronics. Determination of the fracture toughness plays a crucial role for the potential application of topological insulators in flexible electronics and nanoelectro- mechanical dev.ces. Using depth-sensing nanoindentation tests, we inv.stigated for the first time the fracture toughness of bulk single crystals of Bi2Te3 topological insulators, grown using the Bridgmantockbarger method. Our results highlight one of the possible pitfalls of the technology based on topological insulators.

关键词： topological insulators bismuth telluride (Bi2Te3) fracture toughness nanoindentation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nov.l therapy for non-cirrhotic hyperammonemia due to a spontaneous splenorenal shunt

引用

World Journal of Gastroenterology 2014年第25期20卷 8288-8291页

作者： Shari S rogal Angela Hu Rupal Bi Obaid Shaikh Div.sion of Gastroenterology Hepatology and Nutrition University of Pittsburgh Medical Center Pittsburgh PA 15213 United States Univ.rsity of Pittsburgh School of Medicine Pitts-burgh PA 15213 United States Department of Radiology Veterans Affairs Pitts-burgh Healthcare System Pittsburgh PA 15240 United States Div.sion of Gastroenterology Veterans Affairs Pittsburgh Healthcare System Pittsburgh PA 15240 United States

Spontaneous splenorenal shunts in the absence of cirrhosis hav. rarely been reported as a cause hyperammonemia with encephalopathy. Sev.ral closure techniques of such lesions hav. been described. Here we report a case of a patient with no history of liv.r disease who dev.loped significant confusion. After an extensiv. workup, he was found to hav. hyperammonemia and encephalopathy due to formation of a spontaneous splenorenal shunt. There was no ev.dence of cirrhosis on biopsy or imaging and no portal hypertension when directly measured. The shunt was 18 mm and too large for embolization so the segment of the splenic v.in between the portal v.in and the shunt was occluded using an Amplatzer plug. Thus, the superior mesenteric flow was directed entirely to the liv.r. After interv.ntional radiology closure of the shunt using this technique there was complete resolution of *** case represents the first report of a successful closure of splenorenal shunt v.a percutaneous embolization of the splenic v.in with an amplatzer plug using a common femoral v.in approach.

关键词： Splenorenal shunt Gastric bypass Hyperammonemia Encephalopathy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Structural traits of woody plants and geomorphological conditions to the v.getation recov.ry at Ksudach caldera(Southern Kamchatka) since the explosiv. eruption in 1907

引用

Journal of Mountain Science 2020年第7期17卷 1613-1635页

作者： KOPANINA anna v.LEBEDEv. Ekaterina v.v.ASOv. Inna I TALSKIKH Anastasia v Institute of Marine Geology and Geophysics Far Eastern Branch of the Russian Academy of SciencesNauka street1 B693022Yuzhno-SakhalinskRussia Institute of Geography Russian Academy of SciencesStaromonetny s-str.29119017MoscowRussia

This study considers the restoration of the plant cov.r destroyed by a catastrophic v.lcano eruption in the south of Kamchatka Peninsula(the Ksudach caldera,Shtyubel cone),with a particular attention to the role of woody *** aims to qualitativ.ly estimate(at a qualitativ. lev.l)the rate of the primary succession dev.lopment depending on the microrelief and the modern relief-forming *** v.getation recov.ry in the caldera after the Shtyubel cone eruption 109 years ago proceeds slowly and *** proceeds most slowly on a thick tephra mantle continuously disturbed by water and wind erosion,lahars,debris flows,landslides,*** conditions are most typical of the western part of the caldera dominated by pumice fields with occasional patches of pioneer herbs and dwarf *** tundra communities with gradually expanding patches of shrub alder dev.lop in the southern,eastern and northeastern parts of the Ksudach *** 1997 the area of the shrub alder communities has increased by 1.9 times,while the alpine tundra–by 1.3 times *** woody plants(dwarf shrubs and prostrate shrubs)are of particular importance in the process of the v.getation recov.ry on pumice *** suggest that the bark thickness of woody plants is an integrated indicator,which may serv. for estimating the state of ecosystem in the course of the primary succession dev.lopment on juv.nile *** extremely inhospitable env.ronments cause changes in physiological processes in the plant body and in its bark in *** results show that woody plants hav. a"thin"bark and dev.lop some structural-functional arrangements for keeping bark tissues at their ***,the woody plant structure and the rate of changes in plant communities are under control of the geomorphic conditions and primarily–of physicochemical features of the pyroclastic cov.r.

关键词： Ksudach caldera Pioneer species Woody plants Bark Pyroclastic deposits Geomorphological processes

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：