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Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silvera-simón Manel M.santafé Maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

FORGING AsIA′s GLOBAL TRANsPARK IN THE PEARL RIVER DELTA AT ZHUHAI

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Chinese Geographical science 2003年第4期13卷 300-309页

作者： victor F s sIT .

The main purpose of the paper is to introduce the concept of the Global TransPark (GTP). It is a critical time to develop air logistics infrastructure in the New Economy. The paper also presents a brief review of the air cargo industry in the Asian-Pacific region and China,in particular China’s development in the industry as its economy has grown rapidly and globalized in the past two decades. The paper argues that China needs to develop a GTP to support its future growth,and explains why the Pearl River Delta-Hong Kong-Macao city-region or Extended Metropolitan Region (EMR) is the best location. Finally,it proposes that Zhuhai Airport,one of the five airports in the EMR,is the best site for the GTP. New policies from Chinese government as well as close cooperation between local governments of Guangdong and the two special Administrative Regions of Hong Kong and Macao will be needed to make the establishment of the GTP possible.

关键词： Global TransPark airport air cargo transport Hong Kong Extended Metropolitan Region the Pearl River Delta New Economy

TiO_(2)/WO_(3)heterogeneous structures prepared by electrospinning and sintering steps:Characterization and analysis of the impedance variation to humidity

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Journal of Advanced Ceramics 2019年第2期8卷 238-246页

作者： Evando s.ARAuJO victor N.s.LEAO Research Group on Electrospinning and Nanotechnology Applications(GPEA-Nano) Department of Materials ScienceUniversidade Federal do Vale do Sao Francisco

Relative humidity(RH) is a critical environmental variable for transportation and storage of products and for the quality guarantee of several other production processes and services. Heterogeneous structures prepared from the selective semiconductor oxides may improve the sensitivity to humidity due to the better electronic and surface properties, when compared to pristine oxides. This work shows an alternative fabrication route for producing titanium dioxide/tungsten trioxide(TiO2/WO3) heterogeneous structures(by electrospinning and sintering) for potential application on the RH detection. The microstructural properties of the materials were analyzed by scanning electron microscopy(sEM), energy dispersive X-ray analysis(EDs), X-ray diffraction, and Raman spectroscopy. The electrical characterization of the structures was performed by electrical impedance spectroscopy in RH range of 10%–100%. Results indicated a p-to n-type conduction transition at around 30%–40% RH for all tested settings. The analysis of the impedance signature to humidity showed that the amount of fiber layers on the electrode and working temperature are important parameters to improve the humidity sensing of the TiO2/WO3 systems.

关键词： electrospinning heterogeneous structures preparation relative humidity semiconductors

Network coding-aware cache replacement policy in on-demand broadcast environments

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Journal of Harbin Institute of Technology(New series) 2012年第5期19卷 92-100页

作者：陈君 LEE victor C s CHAN Edward school of Information Management Wuhan UniversityWuhan 430072China Dept.of Computer science City University of Hong KongHong KongChina

Network coding has been proved to be an effective technique in improving the performance of data broadcast systems because clients requesting different data items can be served simultaneously in one broadcast. Previous studies showed that its efficiency is highly related to the content of clients' cache. However, existing data broadcast systems do not take network coding information into account when making cache replacement decisions. In this paper, we propose two networks coding-aware cache replacement policies called DLRU and DLRU-CP to supplement network coding assisted data broadcast in on-demand broadcast environments. In DLRU, both data access and decoding contribution are taken into account to make replacement decisions. DLRU-CP is based on DLRU but allows clients to retrieve decodable data items that have not been requested yet. The performance gain of our proposed cache replacement policies over traditional cache replacement policy is shown in the simulation results, which demonstrate conclusively that the proposed policies can effectively reduce the overall response time.

关键词： Network coding cache replacement on-demand broadcast mobile computing

Multi-label Image Classification via Coarse-to-Fine Attention

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Chinese Journal of Electronics 2019年第6期28卷 1118-1126页

作者： LYU Fan LI Linyan victor s.sheng FU Qiming HU Fuyuan school of Electronic and Information Engineering Suzhou University of Science and Technology College of Intelligence and Computing Tianjin University suzhou Institute of Trade and Commerce Department of Computer science Texas Tech University

Great efforts have been made by using deep neural networks to recognize multi-label *** multi-label image classification is very complicated,many studies seek to use the attention mechanism as a kind of guidance. Conventional attention-based methods always analyzed images directly and aggressively, which is difficult to well understand complicated scenes. We propose a global/local attention method that can recognize a multi-label image from coarse to fine by mimicking how human-beings observe images. Our global/local attention method first concentrates on the whole image, and then focuses on its local specific objects. We also propose a joint max-margin objective function, which enforces that the minimum score of positive labels should be larger than the maximum score of negative labels horizontally and vertically. This function further improve our multi-label image classification method. We evaluate the effectiveness of our method on two popular multi-label image datasets(i.e., Pascal VOC and Ms-COCO). Our experimental results show that our method outperforms state-of-the-art methods.

关键词： Multi-label classification Convolutional neural network Recurrent neural network Attention

“What is a sociologist Doing Here?”An Unconventional People-Centered Approach to Improve Warning Implementation in the sendai Framework for Disaster Risk Reduction

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International Journal of Disaster Risk science 2020年第2期11卷 218-229页

作者： victor Marchezini Cemaden–National Early Warning and Monitoring Center of Natural Disasters Distrito de Eug8nio de Melo 12.247-016Sao Jose dos CamposSPBrazil Doctorate Program on Earth system science National Institute for Space ResearchSao Jose dos CamposBrazil Programa de Pós-Gradua??o em Desastres Naturais ICT/Unesp-CemadenSao Jose dos Campos.Brazil

The sendai Framework for Disaster Risk Reduction 2015–2030 recommends several actions for early warning systems(EWss). However, there is a lack of information about their means of implementation. This article used institutional ethnography to analyze the 2012–2018 implementation of a national warning system in Brazil. The challenges related to daily activities, and the interdisciplinary works in the four axes of EWss towards multi-hazard and people-centered approaches are discussed. This national experience is then discussed in the light of the global challenges of EWss considering two main issues:(1) experiences of implementation and barriers related to people-centered warning systems;and(2)types of national/regional warning systems and hazards/threats that are being monitored as an important input for multi-hazard approaches. There are few multi-hazard warning systems in place and EWss are focused on hydrometeorological hazards, mainly related to floods. The sendai Framework needs to improve access to data and information, identify views from the frontline, consider political threats and vulnerabilities, and find ways to talk about disaster risk creation processes at a larger scale.

关键词： Risk governance Interdisciplinary research People-centered warning systems

Cryotic climate conditions and their eventual implication in the high-mountain surface of the Nevado de Toluca volcano, Mexico

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Journal of Mountain science 2021年第9期18卷 2273-2286页

作者： sOTO victor Facultad de Ciencias Biológicas y Agropecuarias Universidad VeracruzanaPoza Rica-Tuxpan 92870México

The state of the cryosphere in tropical regions is of great importance because the temperature around the glaciers, permafrost and snow cover always fluctuates near the melting point. These thermal conditions and their high sensitivity to climate change cause the accelerated disappearance of these elements;therefore, it is important to know the climatic factors that regulate them, as well as the physical characteristics of each cryospheric element. Unlike glaciers, permafrost and snow cover have not been widely studied. In recent decades, the study of the glacial and periglacial environment has been carried out in intertropical mountains. However, despite the altitude of their relief and the frequent occurrence of snowfall in tropical high mountains, the conditions that determine such events have been barely analyzed;and in the case of Mexico, the volume of snowfall and its thickness have not been quantified either, as well as their corresponding duration. Consequently, this work is aimed to analyze the temperature and precipitation conditions that determine the snowfall at the higher part of the Nevado de Toluca volcano;at the same time, the conditions of the cryotic climate and their possible implication on the surface are studied. The analysis of data from 1965 to 2016, using frequency statistics, allowed to realize that snowfall occurs with low intensity, its accumulation being less than 10 cm thick and 10 mm of snow water equivalent, which causes the snowpack to stay only a few weeks on average. At the same time, it was determined that there is a significant increase in the number of freeze-thaw cycles. Therefore, due to the climate conditions and their influence on the mountain surface, it is probable that the bedrock is subject to a greater gelifraction dynamics, and the unconsolidated soil surface increases;the combination of the above could cause a greater geomorphological dynamic over time, particularly due to debris flows, and by water and wind erosion of

关键词： Air temperature Cryotic conditions High-mountain climatology Periglacial geomorphology snow precipitation

Analyses on the Tied-Arch Action of Loaded Reinforced-Concrete Beams with Corroded steel Reinforcement

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Tsinghua science and Technology 2004年第2期9卷 148-152页

作者： victor s. Kamara 刘西拉 Department of Civil Engineering Tsinghua University Beijing 100084 China Department of Civil Engineering Shanghai Jiao Tong University Shanghai 200030 China

The tied-arch action was analyzed by considering 27 reinforced-concrete beams without web reinforcements that were dismantled from a wide range of deteriorated coastal and marine structures and with varying degrees of reinforcement corrosion. Under 2-point loading and changing shear span ratio, changes in loading capacity for beams of the same corrosion degree were studied. Formulas relating ultimate moment of reinforcements with the same corrosion level at increasing a/d ratio were then developed. Load-carrying capacity profile for beams with reinforcement corrosion of 1% and the same cross section was described. The minimum ultimate moment occurs at a/d = 2.5 and at 52% of the full flexural moment, suggesting that the difference in ultimate moment between theoretical and experimental results at the minimum point equals 11%. The results show that the developed theoretical relations compared well with experimental values.

关键词： reinforcement corrosion ultimate moment loading capacity arch action

Utilization of low quality water of mountain reservoirs: a case study from Al Jabal Al Akhdar, Oman

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Journal of Mountain science 2016年第8期13卷 1423-1430页

作者： Mushtaque AHMED Reginald victor Mohammed JAsHOUL B.s. CHOUDRI Department of soils Water and Agricultural Engineering College of Agricultural and Marine SciencesSultan Qaboos University Department of Biology College of ScienceSultan Qaboos University salalah Free Zone Sultanate of Oman Center for Environmental studies and Research Sultan Qaboos University

Al Jabal al Akhdar(Green Mountain) in arid northern Oman has freshwater resources that had supported small communities for hundreds of years. Jabal Akhdar receives more rainfall(300-400 mm) when compared to the desert plains. In the last few years, this region had undergone enormous changes due to rapid development. The resident and transient populations have increased and their activities exert severe stress on the water resources. There are 24 retention reservoirs in the area, but most are eutrophic and the nutrient loading is due to input of animal fecal matter via surface run-off. As expected, these waters contaminated with coliform bacteria and some have pathogenic Escherichia coli. Drinking water needs of all the villages met by groundwater extraction. Because of poor quality, the surface water in the reservoirs is under-utilized. A low-cost lowmaintenance treatment system designed, constructed and operated in one village to clean the reservoir water for non-drinking human use. The treatment unit improved the water quality parameters. A survey among the adult male population of the village showed their eagerness to adopt this system and use the treated reservoir water for uses other than agriculture. Establishment of these treatment units in other villages should reduce the pressures on groundwater extraction.

关键词： Jabal Akhdar Oman Reservoir Eutrophication Treatment society