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Vocalization during copulation behavior in greater horseshoe bats,Rhinolophus ferrumequinum

Chinese Science Bulletin 2013年第17期58卷 2179-2184页

作者： LIU Ying METZNER walter FENG Jiang Jilin Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Department of Integrative Biology & Physiology University of California

Vocal communication plays an important role for individual recognition and male-female interaction during mating in greater horseshoe bats,especially in respect to mate fidelity,which ensures that the bats can maintain a stable social *** studies,however,have addressed the calling behavior during copulating in ***,we initially report the copulation vocalizations and behaviors of both male and female greater horseshoe *** copulation,the male assumed a dorsal position and arched his back,arming around the female using his feet and *** male repeatedly produced very short constant frequency(SCF) syllables with high intensity and repetition rate(male 1:16.48±4.8 ms,male 2:17.79±4.03 ms) when he tried to insert the penis into the female,and then long syllables(male 1:42.08±12.67 ms,male 2:43.02±11.44 ms) after penile *** female bats sometime refused the male bats in the early phase of copulations as emitting noise bursts and broad-band vocalizations,but kept silence during actual *** also found that the SCF copulation calls of one male remained stable peak frequencies on different copulation days although its echolocation call frequency varied each ***,different male individuals maintained their own "private frequency" in the SCF copulation ***,we predicted that the SCF copulation calls may serve as an indicator for female greater horseshoe bats to recognize the mating males in order to maintain mate fidelity because horseshoe bats exhibit sexual segregation before *** results stipulate further studies on mating system and copulation strategies in polygynous *** work may also aid in promoting the preservation of greater horseshoe bats.

关键词：交配行为菊头蝠发声回声定位叫声铁恒定频率 SCF 个人识别

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The effect of surface roughness on claw and adhesive hair performance in the dock beetle Gastrophysa viridula

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Insect Science 2011年第3期18卷 298-304页

作者： James M. R. Bullock walter Federle Department of Zoology University of Cambridge Downing Street Cambridge UK

Natural adhesive systems are adapted to attach to rough surfaces, but the underlying mechanisms have not been fully clarified. Attachment forces for the beetle Gastrophysa viridula were recorded on epoxy casts of surfaces with different roughness using a centrifuge device. Replicas were made of standardized polishing paper with asperity sizes ranging from 0.05 to 30 μm and of dock leaves （Rumex obtusifolius）. Beetles adhered with a safety factor of up to 36 times body weight on smooth substrates or on casts of leaves of their host plant. On the rough substrates, forces were much lower and a minimum at small scale roughness （0.05μm asperity size, with a mean safety factor of S） was observed. Removal of the claws led to a significant reduction in force for rough substrates with asperity sizes ≥ 12 μm. Attachment forces of the hairy adhesive system itself（without the claws） slightly increased from small-scale to large-scale surface roughness, but remained below the level seen on the smooth substrate. This is explained by the inability of setal tips to make full contact to the surface.

关键词： adhesion biomechanics claws locomotion roughness tribology

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Preferred alignments of angular momentum vectors of galaxies in six dynamically unstable Abell clusters

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Research in Astronomy and Astrophysics 2017年第7期17卷 1-10页

作者： Shiv N.Yadav Binil Aryal walter Saurer Central Department of Physics Tribhuvan University Institute of Astro-particle Physics Innsbruck University

A spatial orientation of angular momentum vectors of galaxies in six dynamically unstable Abell clusters（S1171, S0001, A1035, A1373, A1474 and A4053） is studied. For this, twodimensional observed parameters（e.g., positions, diameters and position angles） are converted into three-dimensional（3D） rotation axes of the galaxy using the ＇position angle-inclination＇ method. The expected isotropic distribution curves for angular momentum vectors are obtained by performing random simulations. The observed and expected distributions are compared using several statistical *** preferred alignments of angular momentum vectors of galaxies are noticed in all six dynamically unstable clusters, supporting the hierarchy model of galaxy formation. These clusters have a larger value of velocity dispersion. However, local effects are noticed in the clusters that have substructures in the1D-3D number density maps.

关键词： galaxies evolution - galaxies clusters general- astronomical databases miscellaneous

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Spatiotemporal Variations of Soil Microarthropod Communities in the Negev Desert

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Pedosphere 2016年第4期26卷 451-461页

作者： Haggai WASSERSTROM walter G.WHITFORD Yosef STEINBERGER The Mina and Everard Goodman Faculty of Life Sciences Bar-Ilan University USDA-ARS Jornada Experimental Range MSC 3JER New Mexico State University

Desert ecosystems are characterized by sparse vegetation that affects both abiotic parameters and soil biota along the soil profile. This study was conducted in 2010-2011 in a loess plain in the northern Negev Desert highlands, Israel, to test two main hypotheses： 1） the abundance and diversity of microarthropods would vary seasonally in the top 30-cm soil layer, but would be relatively stable at soil depths between 30 and 50 cm and 2） soil microarthropods would be more abundant in soils under shrubs with large litter accumulations than under shrubs with less litter or bare soil. Soil samples were collected each season from the 0-50 cm profile at 10-cm intervals under the canopies of Hammada scoparia and Zygophyllum dumosum and from the bare interspa^es between them. Soil moisture and soil organic carbon in the top 30-cm layers varied seasonally, but there was little variation in the soil layers deeper than 30 cm. Soil mites were most abundant in the top 30-cm soil layer in autumn and winter, with the highest number of families found in winter. There were no differences in soil microarthropod abundance attributable to the presence or absence of shrubs of either species. The microarthropod communities of the microhabitats studied consisted of Acari, Psocoptera, and Collembola. The Acari were mostly identified to the family level and were dominated by Oribatida （55%） and Prostigmata （41%） in all seasons and microhabitats, while the psocopterans were most abundant in summer. These results are opposite to those obtained in other studies in similar xeric environments. Moreover, our findings were not in line with our hypothesis that a better microhabitat played a major role in microarthropod community composition, diversity, and density.

关键词： microhabitat seasonality shrub soil depth soil mites soil moisture soil organic carbon

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ArcFVS:An integration of a Geographic Information System and Forest Vegetation Simulator

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Science China(Technological Sciences) 2006年第z1期49卷 35-44页

作者： Bogdan Chivoiu John Moser walter L.Mills Department of Forestry and Natural Resources Purdue University 715 West State Street West LafayetteIN 47907USA

This paper presents the design and implementation of an integrated application program called ArcFVS that links the Forest Vegetation Simulator (FVS) and a Geographic Information System (GIS) to realize spatial selection of input files and graphic display of modeling output. Data for testing and running the model came from the U.S. Forest Service's Forest Inventory and Analysis (FIA) Database and were also collected in field surveys in north-central Indiana. ArcFVS 1.0 is designed using the ArcGIS software from the Environmental Systems Research Institute (ESRI) and the Visual Basic for Applications (VBA) programming environment to manipulate ESRI's ArcObjects. The resulting product offers custom functions as commands in a new menu or as tools on a new toolbar. They are used to: select spatially or by attribute the forest plots to be projected by FVS, create the FVS input files for the selected plots and display in a geospatial environment different types of FVS output (text output files, tables with variables of interest and visualization image files). Advantages of ArcFVS 1.0 include the new GIS capabilities, enhanced format translation functions and the standardized programming environment.

关键词： Forest Vegetation Simulator, Geographic Information Systems, forest modeling, graphic interface.

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The pairwise velocity difference of over 2000 BHB stars in the Milky Way halo

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Research in Astronomy and Astrophysics 2009年第11期9卷 1230-1240页

作者： Xiang-Xiang Xue Hans-walter Rix Gang Zhao National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Max-Planck-Institute for Astronomy Konigstuhl 17 D-69117 Heidelberg Germany Graduate University of Chinese Academy of Sciences Beijing 100049 China

Models of hierarchical galaxy formation predict that the extended stellar halos of galaxies like our Milky Way show a great deal of sub-structure, arising from disrupted satellites. Spatial sub-structure is directly observed, and has been quantified, in the Milky Way＇s stellar halo. Phase-space conservation implies that there should be sub-structure in position-velocity space. Here, we aim to quantify such position-velocity sub-structure, using a state-of-the art data set having over 2000 blue horizontal branch （BHB） stars with photometry and spectroscopy from SDSS. For stars in dynamically cold streams （＂young＂ streams）, we expect that pairs of objects that are physically close also have similar velocities. Therefore, we apply the well-established ＂pairwise velocity difference＂（PVD） statistic （｜ △Vlos ｜）（△r）, where we expect （｜ △Vlos ｜） to drop for small separations At. We calculate the PVD for the SDSS BHB sample and find 〈｜ △Vlos ｜〉（△r） ≈ const., i.e. no such signal. By making mock-observations of the simulations by Bullock ＆ Johnston and applying the same statistic, we show that for individual, dynamically young streams, or assemblages of such streams, （｜ △Vlos ｜） drops for small distance separations At, as qualitatively expected. However, for a realistic complete set of halo streams, the pair-wise velocity difference shows no signal, as the simulated halos are dominated by ＂dynamically old＂ phase-mixed streams. Our findings imply that the sparse sampling and the sample sizes in SDSS DR6 are still insufficient to use the position-velocity sub-structure for a stringent quantitative data-model comparison. Therefore, alternate statistics must be explored and much more densely sampled surveys, dedicated to the structure of the Milky Way, such as LAMOST, are needed.

关键词： cosmology dark matter-- galaxies individual (Milky Way) -- galaxy halo -- stars horizontal-branch- stars kinematics

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Practice parameters for the use of actigraphy in the military operational context: the walter Reed Army Institute of Research Operational Research Kit-Actigraphy(WORK-A)

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Military Medical Research 2021年第1期8卷 103-115页

作者： Jaime K.Devine Jake Choynowski Tina Burke Kajsa Carlsson Vincent F.Capaldi Ashlee B.McKeon walter J.Sowden Operational Fatigue and Performance Institutes for Behavior ResourcesBaltimoreMD 21218USA Behavioral Biology Branch Walter Reed Army Institute of Research503 Robert Grant AveSilver SpringMD 20910USA Tripler Army Medical Center HonoluluHI 96859USA

Background: The walter Reed Army Institute of Research(WRAIR) Operational Research Kit-Actigraphy(WORK-A) is a set of unique practice parameters and actigraphy-derived measures for the analysis of operational military sleep patterns. The WORK-A draws on best practices from the literature and comprises 15 additional descriptive variables. Here, we demonstrate the WORK-A with a sample of United States Army Reserve Officers’ Training Corps(ROTC) cadets(n=286) during a month-long capstone pre-commissioning training ***: The sleep of ROTC cadets(n=286) was measured by Philips Actiwatch devices during the 31-day training exercise. The preliminary effectiveness of the WORK-A was tested by comparing differences in sleep measures collected by Actiwatches as calculated by Philips Actiware software against WORK-A-determined sleep measures and self-report sleep collected from a subset of ROTC cadets(n=140).Results: Actiware sleep summary statistics were significantly different from WORK-A measures and self-report sleep(P≤0.001). Bedtimes and waketimes as determined by WORK-A major sleep intervals showed the best agreement with self-report bedtime(22:21±1:30 vs. 22:13±0:40, P=0.21) and waketime(04:30±2:17 vs. 04:31±0:47, P=0.68). Though still significantly different, the discrepancy was smaller between the WORK-A measure of time in bed(TIB) for major sleep intervals(352±29) min and self-report nightly sleep duration [(337±57) min, P=0.006] than that between the WORK-A major TIB and Actiware TIB [(177±42) min, P≤0.001].Conclusions: Default actigraphy methods are not the most accurate methods for characterizing soldier sleep, but reliable methods for characterizing operational sleep patterns is a necessary first step in developing strategies to improve soldier readiness. The WORK-A addresses this knowledge gap by providing practice parameters and a robust variety of measures with which to profile sleep behavior in service members.

关键词： Actigraphy Sleep-wake patterns Military sleep assessment Operational environment Scoring methodology

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Detecting stable phase structures in EEG signals to classify brain activity amplitude patterns

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1483-1491页

作者： Yusely RUIZ Guang LI walter J.FREEMAN Eduardo GONZALEZ Department of Biomedical Engineering Zhejiang University Hangzhou 310027China National Lab of Industrial Control Technology Institute of Cyber-Systems and ControlZhejiang UniversityHangzhou 310027China Department of Molecular&Cell Biology 101 Donner University of California at BerkeleyCA 94720-3206USA

Obtaining an electrocorticograms(ECoG)signal requires an invasive procedure in which brain activity is recorded from the cortical *** contrast,obtaining electroencephalograms(EEG)recordings requires the non-invasive procedure of recording the brain activity from the scalp surface,which allows EEG recordings to be performed more easily on healthy *** this work,a technique previously used to study spatial-temporal patterns of brain activity on animal ECoG was adapted for use on *** main issues are centered on solving the problems introduced by the increment on the interelectrode distance and the procedure to detect stable *** results showed that spatial patterns of beta and gamma activity can also be extracted from the EEG signal by using stable frames as time markers for feature *** adapted technique makes it possible to take advantage of the cognitive and phenomenological awareness of a normal healthy subject.

关键词： Electroencephalograms(EEG) Spatial-temporal pattem Stable phase structure Frames

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An effective simplified model of composite compression struts for partially-restrained steel frame with reinforced concrete infill walls

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Earthquake Engineering and Engineering Vibration 2018年第2期17卷 403-415页

作者： Sun Guohua Chuang-Sheng walter Yang Gu Qiang Reginald DesRoches School of Civil Engineering Suzhou University of Science & Technology School of Civil and Environmental Engineering Georgia Institute of Technology

To resolve the issue regarding inaccurate prediction of the hysteretic behavior by micro-based numerical analysis for partially-restrained（PR）steel frames with solid reinforced concrete（RC）infill walls,an innovative simplified model of composite compression struts is proposed on the basis of experimental observation on the cracking distribution,load transferring mechanism,and failure modes of RC infill walls filled in PR steel *** proposed composite compression struts model for the solid RC infill walls is composed ofαinclined struts and main diagonal ***αinclined struts are used to reflect the part of the lateral force resisted by shear connectors along the frame-wall interface,while the main diagonal struts are introduced to take into account the rest of the lateral force transferred along the diagonal direction due to the complicated interaction between the steel frame and RC infill *** study derives appropriate formulas for the effective widths of theαinclined strut and main diagonal strut,*** example of PR steel frame with RC infill walls simulating simulated by the composite inclined compression struts model is *** maximum lateral strength and the hysteresis curve shape obtained from the proposed composite strut model are in good agreement with those from the test results,and the backbone curve of a PR steel frame with RC infill walls can be predicted precisely when the inter-story drift is within 1%.This simplified model can also predict the structural stiffness and the equivalent viscous damping ratio well when the inter-story drift ratio exceeds 0.5%.

关键词： PR connection steel frame infill walls shear connector hysteretic behavior strut

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An Unconventional Divergence Preserving Finite-Volume Discretization of Lagrangian Ideal MHD

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Communications on Applied Mathematics and Computation 2024年第3期6卷 1665-1719页

作者： walter Boscheri Raphael Loubere Pierre-Henri Maire Dipartimento di Matematica e Informatica University of FerraraFerraraItaly Institut de Mathématiques de Bordeaux(IMB) University of BordeauxTalenceFrance CEA-CESTA Le BarpFrance

We construct an unconventional divergence preserving discretization of updated Lagrangian ideal magnetohydrodynamics(MHD)over simplicial *** cell-centered finite-volume(FV)method employed to discretize the conservation laws of volume,momentum,and total energy is rigorously the same as the one developed to simulate hyperelasticity *** construction this moving mesh method ensures the compatibility between the mesh displacement and the approximation of the volume flux by means of the nodal velocity and the attached unit corner normal vector which is nothing but the partial derivative of the cell volume with respect to the node coordinate under *** is precisely the definition of the compatibility with the Geometrical Conservation Law which is the cornerstone of any proper multi-dimensional moving mesh FV *** momentum and the total energy fluxes are approximated utilizing the partition of cell faces into sub-faces and the concept of sub-face force which is the traction force attached to each sub-face impinging at a *** observe that the time evolution of the magnetic field might be simply expressed in terms of the deformation gradient which characterizes the Lagrange-to-Euler *** this framework,the divergence of the magnetic field is conserved with respect to time thanks to the Piola ***,we solve the fully compatible updated Lagrangian discretization of the deformation gradient tensor for updating in a simple manner the cell-centered value of the magnetic ***,the sub-face traction force is expressed in terms of the nodal velocity to ensure a semi-discrete entropy inequality within each *** conservation of momentum and total energy is recovered prescribing the balance of all the sub-face forces attached to the sub-faces impinging at a given *** balance corresponds to a vectorial system satisfied by the nodal *** always admits a unique solution which provides the nodal velocit

关键词： Cell-centered Lagrangian finite-volume(FV)schemes Hyper-elasticity Ideal magnetohydrodynamics(MHD)equations Moving unstructured meshes A posteriori MOOD limiting

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