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like a G6-nal:transcriptional control of G-protein coupled receptors during oligodendroglial development

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Neural Regeneration Research 2025年第7期20卷 2001-2002页

作者： tim Aberle michael Wegner Institut für Biochemie Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

multilayered control of myelination:Quick,saltatory conduction of action potentials along nerve fibers requires the electrical insulation of axons by myelinating *** the central nervous system,this role is taken up by *** are marked by the expression of the lineage determinants Sox10 and Olig2 and arise from oligodendrocyte precursor cells(OPCs)during embryonal *** the majority of OPCs differentiate into mature oligodendrocytes when nearby axonal segments require myelination,a small subpopulation of OPCs persist as a progenitor ***,the timing of myelination and maintenance of the OPC pool both need to be precisely *** transcription factors either positively or negatively affect oligodendrocyte differentiation and maintenance of the OPC pool as components of a complex gene regulatory network(reviewed in Sock and Wegner,2021).Network activity is additionally influenced by extracellular signaling molecules that bind to receptors on the oligodendroglial cell surface and activate intracellular signaling *** the receptors are linked to the network is poorly understood so far,but pivotal to understanding the overall regulation of central nervous system(CNS)myelination in response to environmental *** insights were recently gained for Gpr37(Schmidt et al.,2024),a G-protein coupled receptor(GPCR)with known relevance in differentiating oligodendrocytes(Yang et al,2016).

关键词： gained insulation conduction

Climate Change modelling and Its Roles to Chinese Crops Yield

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Journal of Integrative Agriculture 2013年第5期12卷 892-902页

作者： JU Hui lIN er-da tim Wheeler Andrew Challinor JIANG Shuai Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Key laboratory of Agro-Environment & Climate Change Ministry of Agriculture Walker Institute for Climate System Research Department of AgricultureUniversity of Reading Institute for Climate and Atmospheric Science School of Earth and EnvironmentThe University of Leeds

Climate has been changing in the last fifty years in China and will continue to change regardless any efforts for mitigation. Agriculture is a climate-dependent activity and highly sensitive to climate changes and climate variability. Understanding the interactions between climate change and agricultural production is essential for society stable development of China. The first mission is to fully understand how to predict future climate and link it with agriculture production system. In this paper, recent studies both domestic and international are reviewed in order to provide an overall image of the progress in climate change researches. The methods for climate change scenarios construction are introduced. The pivotal techniques linking crop model and climate models are systematically assessed and climate change impacts on Chinese crops yield among model results are summarized. The study found that simulated productions of grain crop inherit uncertainty from using different climate models, emission scenarios and the crops simulation models. moreover, studies have different spatial resolutions, and methods for general circulation model （GCm） downscaling which increase the uncertainty for regional impacts assessment. However, the magnitude of change in crop production due to climate change （at 700 ppm CO2 eq correct） appears within ±10% for China in these assessments. In most literatures, the three cereal crop yields showed decline under climate change scenarios and only wheat in some region showed increase. Finally, the paper points out several gaps in current researches which need more studies to shorten the distance for objective recognizing the impacts of climate change on crops. The uncertainty for crop yield projection is associated with climate change scenarios, CO2 fertilization effects and adaptation options. Therefore, more studies on the fields such as free air CO2 enrichment experiment and practical adaptations implemented need to be carried out.

关键词： climate change modelling crop yield impacts China

Analysis of roof and pillar failure associated with weak floor at a limestone mine

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International Journal of mining Science and Technology 2016年第3期26卷 471-476页

作者： murphy michael m. Ellenberger John l. Esterhuizen Gabriel S. m.l.er tim Office of mine Safety and Health Research National Institute of Occupational Safety and Health East Fairfield Company

A limestone mine in Ohio has had instability problems that have led to massive roof falls extending to the surface. This study focuses on the role that weak, moisture-sensitive floor has in the instability *** NIOSH research related to this subject did not include analysis for weak floor or weak bands and recommended that when such issues arise they should be investigated further using a more advanced analysis. Therefore, to further investigate the observed instability occurring on a large scale at the Ohio mine, FlAC3 D numerical models were employed to demonstrate the effect that a weak floor has on roof and pillar stability. This case study will provide important information to limestone mine operators regarding the impact of weak floor causing the potential for roof collapse, pillar failure, and subsequent subsidence of the ground surface.

关键词： Underground limestone Ground control Case study Weak floor Instability

Solvable base change and Rankin-Selberg convolutions

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Science China mathematics 2017年第1期60卷 99-112页

作者： GIllESPIE tim Department of mathematics St. Ambrose University Davenport IA 52803 USA

let π and π′ be unitary automorphic cuspidal representations of Gl_n(A_E) and Gl_m(A_F), and let E and F be solvable Galois extensions of Q of degrees ? and ?′, respectively. Using the fact that the automorphic induction and base change maps exist for E and F, and assuming an invariance condition under the actions of the Galois groups, we attach to the pair(π, π′) a Rankin-Selberg l-function l(s, π×E,Fπ′) for which we prove a prime number theorem. This gives a method for comparing two representations that could be defined over completely different extensions, and the main results give a measure of how many cuspidal components the two representations π and π′ have in common when automorphically induced down to the rational numbers. The proof uses the structure of the Galois group of the composite extension EF and the character groups attached to the fields via class field theory. The second main theorem also gives an indication of when the base change of π up to the composite extension EF remains cuspidal.

关键词： automorphic l-function base change automorphic induction

Antipredator deception in terrestrial vertebrates

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Current Zoology 2014年第1期60卷 16-25页

作者： tim CARO Department of Wildlife Fish and Conservation Biology and Center of Population Biology University of California Davis CA95616 USA

Abstract Deceptive antipredator defense mechanisms fall into three categories： depriving predators of knowledge of prey＇s presence, providing cues that deceive predators about prey handling, and dishonest signaling. Deceptive defenses in terrestrial vertebrates include aspects of crypsis such as background matching and countershading, visual and acoustic Batesian mimicry, active defenses that make animals seem more difficult to handle such as increase in apparent size and threats, feigning injury and death, distractive behaviours, and aspects of flight. After reviewing these defenses, I attempt a preliminary evaluation of which aspects of antipredator deception are most widespread in amphibians, reptiles, mammals and birds

关键词： Amphibians Birds Defenses Dishonesty mammals Prey Reptiles

male circumcision： towards a World Health Organisation normative practice in resource limited settings

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Asian Journal of Andrology 2010年第5期12卷 628-638页

作者： tim Hargreave Senior Fellow School of Clinical Science Edinburgh University Scotland UK Technical Adviser to the WHO RHR -HRP Africa HIV Prevention Male Circumcision Programme

There is now grade 1 evidence that male circumcision （mC） reduces the risk of a man acquiring HIV. modelling studies indicate mC could in the next 10 years save up to 2 million lives in those African countries with high HIV prevalence. Several African countries are now scaling up public health mC programmes. The most effective immediate public health mC programmes in Africa will need to target 18-20 years old men. In the longer term there is a need for infant circumcision programmes. In order to implement more widespread mC there is a need to make the surgical procedures as simple as possible so that safe operations can be performed by paramedical staff. The WHO manual of male Circumcision under local anaesthetic was written with these objectives in mind. Included in the manual are three adult techniques and four paediatric procedures. The adult procedures are the dorsal slit, the for- ceps guided and the sleeve resection methods. Paediatric methods included are the plastibell technique, the mogen and Gomco shield method and a standard surgical dorsal slit procedure. Each method is described in a step by step manner with photographic and line drawing illustrations. In addition to the WHO manual of surgical technique a teaching course has been developed and using this course it has been possible in one week to train a circumcision surgeon who has had no or minimal previous surgical experience. Further scaling will require training of circumcision surgeons, monitoring performance, training the trainer workshops as well as advocacy at national, international and government meetings. In addition to proceeding with standardised methods work is in progress to assess novel techniques in adults such as stay on ring devices and policies are being formulated as to how to assess new devices. Also work is in progress to explore efficiencies in surgical processing by task sharing. Proper informed consent and safety remain paramount and great care has to be taken as programmes in

关键词： Africa HIV male circumcision

Orderly Algorithm to Enumerate Central Groupoids and Their Graphs

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Acta mathematica Sinica,English Series 2007年第2期23卷 249-264页

作者： tim BOYKETT time’s Up Research Department and Department of mathematics Johannes-Kepler University

A graph has the unique path property UPPif there is a unique path of length n betweenany ordered pair of *** paper reiterates Royle and macKay’s technique for constructing orderly *** wishto use this technique to enumerate all UPPgraphs of small orders 3~2 and 4~*** attempt to use thedirect graph formalism and find that the algorithm is *** introduce a generalised problem and derive algebraic and combinatoric structures with appro-priate *** we are able to design an orderly algorithm to determine all UPPgraphs oforder 3~2,which runs fast *** hope to be able to determine the UPPgraphs of order 4~2 in thenear future.

关键词： orderly algorithms paths in directed graphs enumeration

Improving interruption performance of mechanical circuit breakers by controlling pre-current-zero wave shape

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High Voltage 2019年第2期4卷 122-129页

作者： tim Schultz Benjamin Hammerich lorenz Bort Christian m.Franck High Voltage laboratory ETH ZurichPhysikstrasse 38092 ZurichSwitzerland

mechanical circuit breakers(mCBs)are the limiting component for current injection HVDC circuit *** their interruption performance reduces requirements for capacitance and inductance needed in the injection circuit and thus space use and *** performance can be achieved by creating a period of low current gradient before zero crossing in the mCB,*** using a saturable inductor(SI).In this paper,the impact of duration and steepness during the low current-gradient phase is linked to arc parameters of the investigated model gas circuit *** is shown in a scaled experimental setup that an optimum design of the SI can be derived from arc time constant and interruption limits for constant current *** optimisation results in a considerable increase of interruption *** feasibility of implementing an SI in a full-scale HVDC circuit breaker is demonstrated using *** an improved injection scheme,the stresses for the mCB can be reduced ***,the injection circuit components can be scaled down,making the topology more *** reduced interruption requirements might also make it possible to use a single gas interrupter instead of a series connection of vacuum interrupters,reducing the complexity of the mechanical switch.

关键词： performance capacitance wave

Perforated jejunal ulcer associated with gastric mucosa in a jejunal diverticulum

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World Journal of Clinical Cases 2014年第6期2卷 209-210页

作者： John Bunni Helen l Barrett tim A Cook Department of Surgery Gloucester-shire Royal Hospital Department of Pathology Gloucestershire Royal Hospital

Jejunal diverticula are rare and subsequent complications even more so. The usual small bowel diverticulum encountered by general surgeons is a meckel's. These are embryological remnants of the vitello-intestinal duct and are on the anti-mesenteric surface of the terminal ileum. They may contain heterotopic gastric or pancreatic mucosa. Herein we explore the case of a young girl who presented with features of peritonitis secondary to a complication from a jejunal diverticulum. The case, pathology, complications and treatment of jejunal diverticulosis and heterotopic gastric mucosa in the jejunum are explored.

关键词： Jejunum Perforation Heterotopic gastric mucosa meckel’s gastrointestinal diverticulum