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Insect Science 2024年第2期31卷 524-532页

作者： Tomer Urcai Eran Levin Eran Gefen Gal Ribak Faculty of Life Sciences School of ZoologyTel Aviv UniversityTel AvivIsrael Steinhardt Museum of Natural History Israel National Center for Biodiversity StudiesTel AvivIsrael Department of Biology University of Haifa-OranimKiryat TivonIsrael

The scaling of the energetic cost of locomotion with body mass is well documented at the interspecific ***,methodological restrictions limit our understanding of the scaling of flight metabolic rate(MR)in free-flying *** is particularly true at the intraspecific level,where variation in body mass and flight energetics may have direct consequences for the fitness of an *** applied a 13C stable isotope method to investigate the scaling of MR with body mass during free-flight in the beetle Batocera *** species exhibits large intraspecific variation in adult body mass as a consequence of the environmental conditions during larval *** show that the flight-MR scales with body mass to the power of 0.57,with smaller conspecifics possessing up to 2.3 fold higher mass-specific flight MR than larger *** the scaling exponent of free-flight MR was found to be like that determined for tethered-flight,the energy expenditure during free-flight was more than 2.7 fold higher than for *** metabolic cost of flight should therefore be studied under free-flight conditions,a requirement now enabled by the 13C technique described herein for insect flight.

关键词： allometry body mass Coleoptera free-flight insect flight stable carbon isotope tethered-flight

A GHz chirped amplitude-modulated laser for high-contrast plasma gratings

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High Power Laser Science and Engineering 2024年第1期12卷 74-83页

作者： Michael Valdman Amir Hen Gilad Marcus Applied Physics Institute Hebrew University of JerusalemJerusalemIsrael

The generation and control of large amplitude plasma gratings and other plasma structures is of paramount importance for the realization of plasma photonics. Autoresonant excitation of such structures by means of chirped amplitude-modulated lasers has been recently discussed and analyzed theoretically. Here we discuss the parameter space for the realization of such a scheme and describe the laser system that was built towards this goal. We also expand our earlier theoretical study to account for the more realistic case of a moderately focused laser beam, instead of the simplified plane wave approximation.

关键词： amplitude modulation high-frequency modulation autoresonance ion acoustic wave

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Cavity continuum

Photonics Research 2024年第3期12卷 391-398页

作者： FAN CHENG VLADIMIR SHUVAYEV MARK DOUVIDZON LEV DEYCH TAL CARMON School of Electrical Engineering Tel Aviv UniversityTel Aviv 6997801Israel Physics Department Queens College of CUNYFlushingQueensNew York 11367USA Solid State Institute Technion-Israel Institute of TechnologyHaifa 3200003Israel The Graduate Center of CUNY New YorkNew York 10016USA

We experimentally demonstrate and numerically analyze large arrays of whispering gallery *** fluorescent mapping,we measure the spatial distribution of the cavity ensemble’s resonances,revealing that light reaches distant resonators in various ways,including while passing through dark gaps,resonator groups,or resonator *** spatially decays exponentially in the *** practically infinite periodic array of resonators,with a quality factor(Q)exceeding 107,might impact a new type of photonic ensembles for nonlinear optics and lasers using our cavity continuum that is distributed,while having high-Q resonators as unit cells.

关键词： resonator cavity ensemble

PoreScript:Semi-automated pore size algorithm for scaffold characterization

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Bioactive Materials 2022年第7期7卷 1-8页

作者： Dana Jenkins Karim Salhadar Grant Ashby Anita Mishra Joy Cheshire Felipe Beltran Melissa Grunlan Sebastien Andrieux Cosima Stubenrauch Elizabeth Cosgriff-Hernandez Department of Biomedical Engineering University of Texas–AustinAustinTX78712USA Department of Biomedical Engineering Texas A&M UniversityCollege StationTX77843USA Universite de Strasbourg CNRSInstitut Charles Sadron UPR22F-67000StrasbourgFrance Institut für Physikalische Chemie Universitat StuttgartPfaffenwaldring 55D-70569StuttgartGermany

The scaffold pore size influences many critical physical aspects of tissue engineering,including tissue infiltration,biodegradation rate,and mechanical *** measurements of pore sizes from scanning electron micrographs using ImageJ/FIJI are commonly used to characterize scaffolds,but these methods are both time-consuming and subject to user *** semi-automated analysis tools are limited by a lack of accessibility or limited sample size in their verification *** work here describes the development of a new MATLAB algorithm,PoreScript,to address these *** algorithm was verified using three common scaffold fabrication methods(e.g.,salt leaching,gas foaming,emulsion templating)with varying pore sizes and shapes to demonstrate the versatility of this new *** results demonstrate that the pore size characterization using PoreScript is comparable to manual pore size *** PoreScript algorithm was further evaluated to determine the effect of user-input and image parameters(relative image magnification,pixel intensity threshold,and pore structure).Overall,this work validates the accuracy of the PoreScript algorithm across several fabrication methods and provides user-guidance for semi-automated image analysis and increased throughput of scaffold characterization.

关键词： Pore size measurement Polymer scaffolds MATLAB program Tissue engineering

On π-Subpairs of π-Blocks

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Acta Mathematica Sinica,English Series 2006年第6期22卷 1751-1756页

作者： Jin Ke HAI Yi Xin ZHU Department of Mathematics Qingdao University Qingdao 266071 P. R. China Department of Mathematics Capital Normal University Beijing 100037 P. R. China

Alperin and Broug have given the p-subpairs in a finite group, and proved that there is a Sylow theorem for p-subpairs. For a π-separable group with π-Hall subgroup nilpotent, we prove that there is a π-Sylow theor... 详细信息

关键词： π-separable group defect group π-subpair

To Gate, or Not to Gate： Regulatory Mechanisms for Intercellular Protein Transport and Virus Movement in Plants

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Molecular Plant 2011年第5期4卷 782-793页

作者： Shoko Ueki Vitaly Citovsky Institute of Plant Science and Resources Okayama University 2-20-1 Chuo Kurashiki Okayama 710-0046 Japan Department of Biochemistry and Cell Biology State University of New York Stony Brook NY 11794-5215 USA

Cell-to-cell signal transduction is vital for orchestrating the whole-body physiology of multi-cellular organ- isms, and many endogenous macromolecules, proteins, and nucleic acids function as such transported signals. In plants, many of these molecules are transported through plasmodesmata （Pd）, the cell wall-spanning channel structures that interconnect plant cells. Furthermore, Pd also act as conduits for cell-to-cell movement of most plant viruses that have evolved to pirate these channels to spread the infection. Pd transport is presumed to be highly selective, and only a limited repertoire of molecules is transported through these channels. Recent studies have begun to unravel mechanisms that actively regulate the opening of the Pd channel to allow traffic. This macromolecular transport between cells comprises two consecutive steps： intracellular targeting to Pd and translocation through the channel to the adjacent cell. Here, we review the current knowledge of molecular species that are transported though Pd and the mechanisms that control this traffic. Generally, Pd traffic can occur by passive diffusion through the trans-Pd cytoplasm or through the membrane/lu- men of the trans-Pd ER, or by active transport that includes protein-protein interactions. It is this latter mode of Pd trans- port that is involved in intercellular traffic of most signal molecules and is regulated by distinct and sometimes interdependent mechanisms, which represent the focus of this article.

关键词： Plasmodesmata cell-to-cell transport plant viruses transcription factors

Complete Radiation Boundary Conditions for Convective Waves

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Communications in Computational Physics 2012年第2期11卷 610-628页

作者： Thomas Hagstrom Eliane Becache Dan Givoli Kurt Stein Dept.of Mathematics Southern Methodist UniversityDallasTX 75275USA. Propagation des Ondes Etude Mathematique et Simulation(POEMS)INRIADomaine de Voluceau-RocquencourtBP 10578153 Le Chesnay CedexFrance Dept.of Aerospace Engineering TechnionHaifa 32000Israel

Local approximate radiation boundary conditions of optimal efficiency for the convective wave equation and the linearized Euler equations in waveguide geometry are formulated,analyzed,and *** results extend and improve for the convective case the general formulation of high-order local radiation boundary condition sequences for anisotropic scalar equations developed in[4].

关键词： Radiation boundary conditions convective waves

Catalysts for the hydrogen evolution reaction in alkaline medium:Configuring a cooperative mechanism at the Ag-Ag_(2)S-MoS_(2) interface

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Journal of Energy Chemistry 2022年第11期31卷 481-488,I0013页

作者： Avraham Bar-Hen Simon Hettler Ashwin Ramasubramaniam Raul Arenal Ronen Bar-Ziv Maya Bar Sadan Department of Chemistry Ben-Gurion University of the NegevBeer-Sheva 8410501Israel Department of Chemistry Nuclear Research Center NegevP.O.Box 9001Beer-Sheva 84190Israel Laboratorio de Microscopías Avanzadas Universidad de Zaragoza50018 ZaragozaSpain Instituto de Nanociencia y Materiales de Aragon CSIC-U.de ZaragozaCalle Pedro Cerbuna 1250009 ZaragozaSpain Department of Mechanical and Industrial Engineering University of MassachusettsAmherstMA 01003United States ARAID Foundation 50018 ZaragozaSpain

Designing electrocatalysts for HER in alkaline conditions to overcome the sluggish kinetics associated with the additional water dissociation step is a recognized challenge in promoting the hydrogen *** this end,delicately tuning the atomic-scale structure and surface composition of nanoparticles is a common strategy and,specifically,making use of hybrid structures,can produce synergistic effects that lead to highly active ***,we present a core-shell catalyst of Ag@MoS_(2)that shows promising results towards the hydrogen evolution reaction(HER)in both 0.5 M H_(2)SO_(4)and 0.5 M *** this hybrid structure,the MoS_(2)shell is strained and defective,and charge transfer occurs between the conductive core and the shell,contributing to the electrocatalytic *** shelling process results in a large fraction of Ag_(2)S in the cores,and adjusting the relative fractions of Ag,Ag_(2)S,and MoS_(2)leads to improved catalytic activity and fast charge-transfer *** suggest that the enhancement of alkaline HER is associated with a cooperative effect of the interfaces,where the Ag(Ⅰ)sites in Ag_(2)S drive the water dissociation step,and the formed hydrogen subsequently recombines on the defective MoS_(2)*** study demonstrates the benefits of hybrid structures as functional nanomaterials and provides a scheme to activate MoS_(2)for HER in alkaline conditions.

关键词： Water splitting Core-shell Catalytic mechanism Electrocatalysis 2D materials

Speculations on the W-mass measurement at CDF

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Chinese Physics C 2022年第12期46卷 145-161页

作者：顾嘉荫刘真马腾舒菁 Department of Physics and Center for Field Theory and Particle Physics Fudan UniversityShanghai 200438China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China School of Physics and Astronomy University of MinnesotaMinneapolisMN 55455USA Physics Department Technion Israel Institute of TechnologyHaifa 3200003Israel CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China International Center for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

The W mass determination at the Tevatron CDF experiment reported a deviation from the SM expectation at the 7σ*** discuss a few possible interpretations and their collider *** perform electroweak global fits under various frameworks and *** consider three types of electroweak global fits in the effective-field-theory framework:the S-T,S-T-δG_(F),and eight-parameter flavor-universal *** discuss the amounts of tensions between different m_(W)measurements reflected in these fits and the corresponding shifts in central values of these *** these electroweak fit pictures in hand,we present a few different classes of models and discuss their compatibility with these *** find that while explaining the m_(W)discrepancy,the single gauge boson extensions face strong LHC direct search constraints unless the Z′is fermiophobic(leptophobic),which can be realized if extra vector fermions(leptons)mix with the SM fermions(leptons).Vector-like top partners can partially generate the needed shift to the electroweak *** compatibility with the top squark is also studied in *** find that the non-degenerate top squark soft masses enhance the needed operator coefficients,enabling an allowed explanation compatible with current LHC ***,more theoretical and experimental developments are highly in demand to reveal the physics behind this discrepancy.

关键词： W mass EWPT Z-prime vector-like quark SUSY squark

Efficient network immunization under limited knowledge

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National Science Review 2021年第1期8卷 127-134页

作者： Yangyang Liu Hillel Sanhedrai Gao Gao Dong Louis M.Shekhtman Fan Wang Sergey V.Buldyrev Shlomo Havlin Department of Systems Science National University of Defense Technology Department of Physics Bar-Ilan University Faculty of Science Jiangsu University Network Science Institute Northeastern University Department of Physics Yeshiva University

Targeted immunization of centralized nodes in large-scale networks has attracted significant ***, in real-world scenarios, knowledge and observations of the network may be limited, thereby precluding a full assessment of the optimal nodes to immunize（or quarantine） in order to avoid epidemic spreading such as that of the current coronavirus disease（COVID-19） epidemic. Here, we study a novel immunization strategy where only n nodes are observed at a time and the most central among these n nodes is immunized. This process can globally immunize a network. We find that even for small n（≈10） there is significant improvement in the immunization（quarantine）, which is very close to the levels of immunization with full knowledge. We develop an analytical framework for our method and determine the critical percolation threshold p;and the size of the giant component P∞ for networks with arbitrary degree distributions P（k）. In the limit of n →∞ we recover prior work on targeted immunization, whereas for n = 1 we recover the known case of random immunization. Between these two extremes, we observe that, as n increases,p;increases quickly towards its optimal value under targeted immunization with complete information. In particular, we find a new general scaling relationship between |p;（∞）-p;（n）| and n as |p;（∞）-p;（n）| ～n;exp（-αn）. For scale-free（SF） networks, where P（k）～ k;, 2 < γ < 3, we find that p;has a transition from zero to nonzero when n increases from n = 1 to O（log N）(where N is the size of the network). Thus, for SF networks, having knowledge of ≈log N nodes and immunizing the most optimal among them can dramatically reduce epidemic spreading. We also demonstrate our limited knowledge immunization strategy on several real-world networks and confirm that in these real networks, p;increases significantly even for small n.

关键词： percolation complex networks network immunization critical phenomena