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Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： victor V.Chizhikov Igor Y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).while the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

Overview of automotive engine friction and reduction trends-Effects of surface, material, and lubricant-additive technologies

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Friction 2016年第1期4卷 1-28页

作者： victor w.wONG Simon C.TUNG Massachusetts Institute of Technology Cambridge MA 02139 USA Vanderbilt Chemicals LLC Norwalk CT 06856 USA

The increasing global environmental awareness, evidenced by recent worldwide calls for control of climate change and greenhouse emissions, has placed significant new technical mandates for automotives to improve engine efficiency, which is directly related to the production of carbon dioxide, a major greenhouse gas. Reduction of parasitic losses of the vehicle, powertrain and the engine systems is a key component of energy conservation. For engine efficiency improvement, various approaches include improvements in advanced combustion systems, component system design and handling—such as down-sizing, boosting, and electrification—as well as waste heat recovery systems etc. Among these approaches, engine friction reduction is a key and relatively cost-effective approach, which has been receiving significant attention from tribologists and lubricant-lubrication engineers alike. In this paper, the fundamentals of friction specific to the environments of engine components tribology are reviewed, together with discussions on the impact of developing vehicle powertrain technologies, surface and material technologies, as well as lubricant and additive technologies on promises of continuing friction and wear reduction trends. The international accords on climate change require further gains in fuel efficiency and energy sustainability from all industry sectors including those in the automotive and the broader internal combustion engine industries, and the latter encompass off-highway, power generation, marine, and rail industries as well. This paper focsuses on friction reduction in mainly automotive engines, however. The paper starts with a clarification of the common descriptors of mechanical losses and friction in the engine, followed by the topic of lubrication fundamentals such as lubrication regimes. Then the lubrication of the contacting surfaces in each of the major engine subsystems is discussed in turn. These subsystems include the piston assembly: ring-pack/liner,

关键词： powertrain tribology automotive lubricants additive formulation mechanical design surface coatings and textures friction wear

Current endoscopic approach to indeterminate biliary strictures

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world Journal of Gastroenterology 2012年第43期18卷 6197-6205页

作者： David w victor Stuart Sherman Tarkan Karakan Mouen A Khashab Department of Medicine Johns Hopkins Hospital Baltimore MD 21287 United States Department of Medicine Indiana University School of Medicine Indianapolis IN 46202 United States Department of Medicine Gazi University 06710 Ankara Turkey

Biliary strictures are considered indeterminate when basic work-up, including transabdominal imaging and endoscopic retrograde cholangiopancreatography with routine cytologic brushing, are non-diagnostic. Indeterminate biliary strictures can easily be mischaracterized which may dramatically affect patient's outcome. Early and accurate diagnosis of malignancy impacts not only a patient's candidacy for surgery, but also potential timely targeted chemotherapies. A significant portion of patients with indeterminate biliary strictures have benign disease and accurate diagnosis is, thus, paramount to avoid unnecessary surgery. Current sampling strategies have suboptimal accuracy for the diagnosis of malignancy. Emerging data on other diagnostic modalities, such as ancillary cytology techniques, single operator cholangioscopy, and endoscopic ultrasonography-guided fine needle aspiration, revealed promising results with much improved sensitivity.

关键词： Indeterminate stricture Bile duct Single operator cholangioscope Cholangioscopy Endoscopic ultrasound Endoscopic retrograde cholangiopancrea-tography Bile duct stricture Indeterminate biliary stricture Confocal microscopy Transpapillary biopsy Cholangiocarcinoma Primary sclerosing cholangitis Spyglass

“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

Transnational Dialogues on Interdisciplinary Approaches for Advancing People-Centered warning Systems

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International Journal of Disaster Risk Science 2023年第5期14卷 868-872页

作者： victor Marchezini Cemaden–National Early warning and Monitoring Centre of Natural Disasters São Josédos Campos12.247-016Brazil Natural Hazards Center Institute of Behavioral ScienceUniversity of Colorado BoulderBoulderCO80309USA

The United Nations Office for Disaster Risk Reduction and the world Meteorological Organization launched in 2022 the executive plan of the world program "Early warning Systems for All" to be implemented from 2023 to *** program champions an investment of USD 3.1 billion into the four pillars of warning systems and calls for multi-hazard and peoplecentered warning systems(PCwS).However,there is a scientific gap concerning interdisciplinary approaches to promoting *** by the call for action of "Early warning Systems for All" and warning research gaps on the lack of interdisciplinarity,a workshop series "Interdisciplinary Approaches for Advancing People-Centered warning Systems" was held in early *** short article shares the preliminary findings and recommendations of this research,which involved a transnational virtual dialogue between one scientific organization in Brazil and one from the United *** findings and recommendations discussed in three virtual sessions and one collective working paper were centered on three aspects:promoting interdisciplinary integration in research;the need to discuss the characteristics of a PCwS;and promoting problem-and solution-based programs with people to integrate them at all phases of the warning system.

关键词： Capacity building Cooperation Interdisciplinary methods warning implementation warning research

Miscellaneous Rotating Solitary waves to a Coupled Dispersionless System

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Chinese Physics Letters 2009年第9期26卷 61-64页

作者： Kuetche Kamgang victor Ecole Nationale Superieure Polyteehnique University of Yaounde I PO Box 8390 Cameroon Department of Physics Faculty of Science University of Yaounde I PO Box. 812 Cameroon Higher Teacher's Training College of Maroua University of Maroua P.O. Box. 46 Cameroon The A bdus Salam International Centre for Theoretical Physics P.O. Box 586 Strada Costiera II-34014 Trieste Italy

we investigate the soliton structure of a coupled dispersionless system describing a current-conducting string with infinite length within a magnetic field. Thus, following Hirota＇s method, we unwrap three typical localized waves with nonzero angular momentum depending strongly upon their angular velocities. Illustrating the soliton behavior of these waves, we focus our interests on breather-like waves and depict the elastic scattering amongst such waves.

关键词： sea surface nonliear interaction numerical method

Stereodynamics of O（^3P）＋H2 at Scattering Energies of 0.5, 0.75, and 1.0 eV

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Chinese Journal of Chemical Physics 2010年第2期23卷 149-154,I0001页

作者： victor wei-keh wu 国立高雄应用科技大学、化学材料工程系高雄80782 胜利者基础研究实验室、比勒费尔德D-33602 德国

Quasiclassical trajectory calculation of the title reaction O（^3P）＋H2→OH＋H at three different scattering energies of 0.5, 0.75, and 1.0 eV on the lowest electronic potential energy surface 1^3A＂ has been done. Distribution P（θr） of polar angles between the relative velocityk of the reactant and rotational angular momentum vector j＇ of the product, distribution P（φr） of the azimuthal as well as dihedral angles correlating k-k＇-j＇, 3-dimensional distri-bution, and polarization-dependent differential cross sections （PDDCSs）dependent upon the scattering angle of the product molecule OH between the relative velocity k of the reactant and k＇ of the product at different scattering energies of 0.5, 0.75, and 1.0 eV are presented and discussed.

关键词： Quasiclassical trajectory calculation Stereodynamics Alignment Rotational angular momentum Polarization-dependent differential cross section O+H2 reaction

Mathematics of microRNAs: stabilizing gene regulatory networks

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National Science Review 2019年第6期6卷 1189-1190页

作者： victor Ambros Program in Molecular Medicine University of Massachusetts Medical School

Micro RNAs(miRNAs) are fascinating in their versatility. Animal cells express hundreds of distinct micro RNAs, and each micro RNA can regulate hundreds of distinct m RNA ***, in aggregate, the micro RNA compliment of a cell can exert pervasive effects on gene expression. Individual micro RNAs can also be potent determinants of phenotype: The

关键词： RNA stabilizing gene regulatory networks Mathematics of microRNAs