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Fine structural description of the compound eye of the Madagascar ＇hissing cockroach＇ Gromphadorhinaportentosa （Dictyoptera： Blaberidae）

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Insect Science 2008年第2期15卷 179-192页

作者： Monalisa Mishra victor Benno Meyer-Rochow Faculty of Engineering and Sciences Jacobs University (formerly known as International University Bremen) Bremen Germany Department of Biology (Elainmuseo) University of Oulu Oulu Finland

The compound eyes of the wingless adults of the Madagascar ＇hissing cockroach＇ Gromphadorhinaportentosa Sachum, 1853 were examined by light and electron microscopy. Each eye contains 2 400-2 500 mostly hexagonal facets. However, irregularities affecting both shape and size of the ommatidia are relatively common, especially towards the margins of the eye. An individual ommatidium of this eucone type of apposition eye contains eight retinula cells, which give rise to a centrally-fused, tiered rhabdom. The distal end of the latter is funnel-shaped and accommodates the proximal end of the cone in its midst, Further below, the rhabdom （then formed by the rhabdomeres of four retinula cells） assumes a squarish profile with microvilli aligned in two directions at right-angle to each other. Cross sections through the proximal regions of the rhabdom display triangular rhabdom outlines and microvilli （belonging to 3-4 retinula cells different from those involved in the squarish more distal rhabdom） that run in three directions inclined to one another by 120°. Overall the organization of the eye conforms to the orthopteroid pattern and particularly closely resembles that of the American cockroach Periplaneta americana. However, since G. portentosa possesses fewer ommatidia, this could be a consequence of its inability to fly. On the other hand, the large size of the facets and the voluminous rhabdoms suggest considerable absolute sensitivity and an ability to detect the plane of linearly polarized light. Based on the pattern of microvillus orientations in combination with the crepuscular lifestyle G. portentosa leads and the habitat it occurs in, the prediction is made that this insect uses its green receptors for e-vector discrimination in the environment of down-welling light that reaches the forest floor.

关键词： apposition blattodea closed rhabdom ommatidium polarization vision

Wrapping up the role of pericytes in Parkinson's disease

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Neural Regeneration Research 2023年第11期18卷 2395-2396页

作者： Taylor John Stevenson Birger victor Dieriks Department of Pharmacology University of AucklandAucklandNew Zealand Centre for Brain Research University of AucklandAucklandNew Zealand Department of Anatomy and Medical Imaging University of AucklandAucklandNew Zealand

Pericytes are classically defined as contra ctile cells within the central nervous system that regulate blood flow and permeability of the blood-brain barrier(BBB).This one-sided view is gradually changing,and pericytes are now considered versatile cells that can switch their function in response to different stimuli(Uemura et al.,2020).In addition to their role as gatekeepers of the BBB and maintaining homeostasis of the brain’s microenvironment through adj usting the vascular intraluminal dia meter,pericytes are both sensors and initiators of inflammation.

关键词： homeostasis pericyte

CD74 in antigen presentation,inflammation,and cancers of the gastrointestinal tract

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World Journal of Gastroenterology 2009年第23期15卷 2855-2861页

作者： Ellen J Beswick victor E Reyes Department of Pediatrics University of Texas Medical Branch Galveston TX 77555 United States Department of Pediatrics and Microbiology and Immunology University of Texas Medical Branch Galveston TX 77555 United States

CD74 is a protein whose initial role in antigen presentation was recognized two decades ago. Recent studies have revealed that it has additional functions as a receptor for macrophage migration inhibitory factor and as a receptor for an important human pathogen, Helicobacter pylori （H pylon）. The role of CD74 as a receptor is important because after binding of migration inhibitory factor or H pylori, NF-κB and Erkl/2 activation occurs, along with the induction of proinflammatory cytokine secretion. This review provides an up-to-date account of the functions of CD74 and how it might be involved in inflammation and cancer within the gastrointestinal tract.

关键词： CD74 Invariant chain Cancer Inflammation Helicobacterpylori Gastrointestinal tract

Stepwise magnetization reversal of geometrically tuned in diameter Ni and FeCo bi-segmented nanowire arrays

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Nano Research 2019年第7期12卷 1547-1553页

作者： Ester M. Palmero Miguel Mendez Silvia Gonzalez Cristina Bran victor Vega Manuel Vazquez victor M. Prida Institute of Materials Science of Madrid (ICMM-CSIC) Madrid 28049Spain Department of Physics University of OviedoFederico Garda Lorca 18Oviedo 33007Spain Division of Permanent Magnets and Applications IMDEA NanoscienceMadrid 28049Spain

Magnetization reversal processes of hexagonal dense arrays of bi-segmented Ni and Fe50Co50 nanowires consisting of two well defined diameters (45 and 80 nm) have been *** nanowires were grown inside of tailored pores of anodic alumina templates by combined anodization,atomic layer deposition (ALD) and electrodeposition *** experiments have allowed to identify their two-step magnetization reversal process ascribed to the respective segments of different *** is concluded from the differential susceptibility observed in the hysteresis loops,contrary to those for nanowires with homogeneous *** results are also confirmed by the first-order reversal curve (FORC) distribution diagrams,where an elongation parallel to the interaction axis around two coercive field values is obtained,which is correlated to the difference in diameter of the two *** well-defined two-step magnetization reversal process through the nanowire diameter design is thought to be very useful for the advanced control of the remagnetization in arrays of magnetic multidomain systems.

关键词： Bi-segmented nanowires nickel iron cobalt alloy stepwise magnetization reversal first-order reversal curve (FORC)

Extending blending proportions of ordinary Portland cement and calcium sulfoaluminate cement blends:Its effects on setting,workability,and strength development

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Frontiers of Structural and Civil Engineering 2021年第5期15卷 1249-1260页

作者： Guangping HUANG Deepak PUDASAINEE Rajender GUPTA Wei victor LIU Department of Civil and Environmental Engineering University of AlbertaEdmonton T6G 1H9Canada Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 1H9Canada

This study extended blending proportion range of ordinary Portland cement(OPC)and calcium sulfoaluminate(CSA)cement blends,and investigated effects of proportions on setting time,workability,and strength development of OPC-CSA blend-based *** analysis(TGA)and X-ray diffraction(XRD)were conducted to help understand the performance of OPC-CSA blend-based *** setting time of the OPC-CSA blends was extended,and the workability was improved with increase of OPC *** the early-age strength decreased with increase of OPC content,the strength development was still very fast when the OPC content was lower than 60%due to the rapid formation and accumulation of *** 2 h,the OPC-CSA blend-based mortars with OPC contents of 0%,20%,40%,and 60%achieved the unconfined compressive strength(UCS)of 17.5,13.9,9.6,and 5.0 MPa,*** OPC content had a negligible influence on long-term *** 90 d,the average UCS of the OPC-CSA blend-based mortars was 39.2±1.7 MPa.

关键词： calcium sulfoaluminate cement cement blends hydration reaction setting workability compressive strength

E-beam generation in discharges initiated by voltage pulses with a rise time of 200 ns at an air pressure of 12.5-100 kPa

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Plasma Science and Technology 2019年第4期21卷 52-60页

作者： victor TARASENKO Dmitry BELOPLOTOV Mikhail LOMAEV Dmitry SOROKIN Institute of High Current Electronics Siberian Bran ch.Russian Academy of Sciences.Tomsk&34055.Russia National Research Tomsk State University.Tomsk 634050 Russia

The effect of air pressure(12.5,25,50,and 100 kPa)on the gen eration of runaway electron beams in a non-uniform electric field when applying voltage pulses(~35 kV)with a rise time of?200 ns has been *** results show that the discharge has various stages:streamer,diffuse,and ***,a wide streamer develops in the gap and a diffuse discharge is formed.A spark is formed u 100 ns after the *** current pulse of a supershort avalanche electron beam(SAEB)was measured with a collector at various pressures of *** show that there are two modes of generation of run away *** an air pressure of 25-100 kPa,a single SAEB current pulse with a full width at half-maximum(FWHM)of 120-140 ps is *** the air pressure of 12.5 kPa,two current pulses of the electron beam are *** of the first and second current pulses are ul40ps and u300 ps,*** current pulse amplitude of the second electron beam is higher than that of the first one,but the electron energy is less.

关键词： diffuse discharge runaway electrons streamer breakdown displacement current

基于深度强化学习的空天地一体化网络信息物理系统垂直切换策略

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通信学报 2024年第8期45卷 180-191页

作者：武艳潘广川姚明旿杨清海梁中明西安电子科技大学空天地一体化综合业务网全国重点实验室陕西西安710071 深圳大学计算机与软件学院物联网研究中心广东深圳518060

针对空天地一体化网络信息物理系统模型复杂、很难获得网络拓扑先验知识和模型化假设的特点,研究其基于深度强化学习的垂直切换策略。首先,综合考虑系统稳定性、切换开销和网络使用成本约束,将垂直切换策略问题建模为约束马尔可夫决策过... 详细信息

针对空天地一体化网络信息物理系统模型复杂、很难获得网络拓扑先验知识和模型化假设的特点,研究其基于深度强化学习的垂直切换策略。首先,综合考虑系统稳定性、切换开销和网络使用成本约束,将垂直切换策略问题建模为约束马尔可夫决策过程(CMDP),并给出保证可行解存在的充分条件;其次,提出约束-近端策略优化(CPPO)算法解决该问题,并在基站侧引入分布式强化学习机制加速训练收敛。相较于基准策略,仿真验证了所提垂直切换策略的优越性和有效性。

关键词：空天地一体化网络信息物理系统深度强化学习垂直切换

Appraising the potential of calcium sulfoaluminate cement-based grouts in simulated permafrost environments

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Frontiers of Structural and Civil Engineering 2023年第5期17卷 722-731页

作者： Jian ZHAO Guangping HUANG Lin LIAO Wei victor LIU Department of Civil and Environmental Engineering University of AlbertaEdmonton T6G 1H9Canada College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China

The aim of this study is to appraise the potential of calcium sulfoaluminate(CSA)cement-based grouts in simulated permafrost *** hydration and performance of CSA cement-based grouts cured in cold environments(10,0,and−10℃)are investigated using a combination of tests,including temperature recording,X-ray diffraction(XRD)tests,thermogravimetric analysis(TGA),and unconfined compressive strength(UCS)*** recorded temperature shows a rapid increase in temperature at the early stage in all the ***,results of the TGA and XRD tests show the generation of a significant quantity of hydration products,which indicates the rapid hydration of CSA cement-based grouts at the early stage at low ***,the CSA cement-based grouts exhibit remarkably high early *** UCS values of the samples cured for 2 h at−10,0,and 10℃ are 6.5,12.0,and 12.3 MPa,*** UCS of the grouts cured at−10,0,and 10℃ increases continuously with age and ultimately reached 14.9,19.0,and 30.6 MPa at 28 d,*** findings show that the strength of grouts fabricated using CSA cement can develop rapidly in cold environments,thus rendering them promising for permafrost applications.

关键词： permafrost low temperatures calcium sulfoaluminate cement-based grouts hydration reaction compressive strength

Implicit large eddy simulation of unsteady cloud cavitation around a plane-convex hydrofoil

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Journal of Hydrodynamics 2015年第6期27卷 815-823页

作者： HIDALGO victor 罗先武 ESCALER Xavier 季斌 AGUINAGA Alvaro Beijing Key Laboratory of CO2 Utilization and Reduction Technology Tsinghua University CDIF Universitat Politècnica de Catalunya School of Power and Mechanical Engineering Wuhan University Mechanical Engineering Department Escuela Politecnica Nacional University

The present paper focuses on the erosive cavitation behavior around a plane convex hydrofoil. The Zwart-Gerber-Belamri cavitation model is implemented in a library form to be used with the OpenFOAM. The implicit large eddy simulation （ILES） is app- lied to analyze the three-dimensional unsteady cavitating flow around a plane convex hydrofoil. The numerical results in the cases under the hydrodynamic conditions, which were experimentally tested at the high speed cavitation tunnel of the l^cole Polytechnique F6d＆ale de Lausanne （EPFL）, clearly show the sheet cavitation development, the shedding and the collapse of vapor clouds. It is noted that the cavitation evolutions including the maximum vapor length, the detachment and the oscillation frequency, are captured fairly well. Furthermore, the pressure pulses due to the cavitation development as well as the complex vortex structures are reasona- bly well predicted. Consequently, it may be concluded that the present numerical method can be used to investigate the unsteady cavitation around hydrofoils with a satisfactory accuracy.

关键词： implicit large eddy simulation (ILES) unsteady partial cavitation Zwart-Gerber-Belamri cavitation model OpenFOAM,Q - criterion