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Science China(Technological Sciences) 2000年第4期43卷 387-394页

作者：刘恩儒 queen john h 张中杰陈东 Institute of Geophysics Chinese Academy of SciencesBeijing 100101China British Geological Survey Edinburgh EH9 3LAUK Concoco Inc. HoustonUSA77079

A 2D elastodynamic boundary element method (BEM) is used to solve multiple scattering of elastic waves. The method is based on the integral representation of an elastic wave-field by assuming a fictitious source distribution on the scattering objects or inclusions, i.e. a mathematical description of huygens’ principle, and the fictitious source distribution can be found by matching appropriate boundary conditions at the boundary of the inclusions. Numerical studies show that in the presence of cracks, spatial and scale-length distributions are important and different spatial arrangements of the same scatters lead to profound differences in scattering characteristics, in particular the frequency contents of the transmitted wave-fields. The frequency characteristics, such as the frequency of peak attenuation , can be related to spatial size parameters of the model.

关键词： seismic waves multiple scattering inclusions BEM.

Large anisotropic negative thermal expansion in Cu-TDPAT metalorganic framework:A combined in situ X-ray diffraction and DRIFTS study

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Nano Research 2021年第2期14卷 404-410页

作者： Mehrdad Asgari lia Kochetygov hassan Abedini Wendy L.queen Institut des Sciences et Ingenierie Chimiques Ecole Polytechnique Federale de Lausanne(EPFL)-Valais WallisCH-1951 SionSwitzerland Gas Engineering Department Faculty of PetroleumPetroleum University of Technology(PUT)Ahwaz 61991-71183Iran

Cu-TDPAT(h_(6)TDPAT=2,4,6-tris(3,5-dicarboxylphenylamino)-1,3,5-triazine),a stable nanoporous metal-organic framework with rht topology,has sparked broad interest as an adsorbent for several chemical separation *** this work,in situ synchrotron diffraction experiments followed by sequential LeBail refinements reveal that Cu-TDPAT shows unusually large anisotropic negative thermal expansion(NTE).The PASCal crystallography tool,used to analyze the magnitude of the NTE,reveals an average volumetric thermal expansion coefficientαv=-20.3 MK^(-1).This value is significantly higher than the one reported for Cu-BTC(also known as hKUST-1),which contains the same Cu-paddlewheel building unit,αv=-12 MK^(-1).In situ synchrotron single crystal X-ray diffraction and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)were employed to shed light on the NTE *** these two methods,we were able to elucidate the three main structural motions that are responsible for the NTE *** more pronounced NTE behavior of Cu-TDPAT is attributed to the lower symmetry combined with the more complex ligand structure when compared to *** knowledge obtained in this work is important for understanding the behavior of the adsorbent under transient variable temperature conditions in fixed adsorption beds.

关键词： negative thermal expansion metal-organic frameworks Cu-TDPAT in situ diffraction in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)

Reverse-Time Prestack Depth Migration of GPR Data from Topography for Amplitude Reconstruction in Complex Environments

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Journal of Earth Science 2015年第6期26卷 791-798页

作者： john h.Bradford Center for Geophysical Investigation of the Shallow Subsurface Boise State University

With increased computational power, reverse-time prestack depth migration（RT-PSDM） has become a preferred imaging tool in seismic exploration, yet its use has remained relatively limited in ground-penetrating radar（GPR） applications. Complex topography alters the wavefield kinematics making for a challenging imaging problem. Model simulations show that topographic variation can substantially distort reflection amplitudes due to irregular wavefield spreading, attenuation anomalies due to irregular path lengths, and focusing and defocusing effects at the surface. The effects are magnified when the topographic variations are on the same order as the depth of investigation––a situation that is often encountered in GPR investigations. here, I use a full wave-equation RT-PSDM algorithm to image GPR data in the presence of large topographic variability relative to the depth of investigation. The source and receiver wavefields are propagated directly from the topographic surface and this approach inherently corrects for irregular kinematics, spreading and attenuation. The results show that when GPR data are acquired in areas of extreme topography, RT-PSDM can accurately reconstruct reflector geometry as well as reflection amplitude.

关键词： reverse-time prestack depth migration ground-penetrating radar topography wavefield reflector geometry reflection amplitude.

harnessing neural activity to promote repair of the damaged corticospinal system after spinal cord injury

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Neural Regeneration Research 2016年第9期11卷 1389-1391页

作者： john h.Martin Department of Physiology Pharmacology & NeuroscienceCity University of New York School of Medicine

As most spinal cord injuries （SCIs） are incomplete, an important target for promoting neural repair and recovery of lost motor function is to promote the connections of spared descending spinal pathways with spinal motor circuits. Among the pathways, the corticospinal tract （CST） is most associated with skilled voluntary functions in humans and many animals. CST loss, whether at its origin in the motor cortex or in the white matter tracts subcortically and in the spinal cord, leads to movement impairments and paraly- sis. To restore motor function after injury will require repair of the damaged CST. In this review, I discuss how knowledge of activity-dependent development of the CST--which establishes connectional speci- ficity through axon pruning, axon outgrowth, and synaptic competition among CST terminals--informed a novel activity-based therapy for promoting sprouting of spared CST axons after injur in mature animals. This therapy, which comprises motor cortex electrical stimulation with and without concurrent trans-spi- nal direct current stimulation, leads to an increase in the gray matter axon length of spared CST axons in the rat spinal cord and, after a pyramidal tract lesion, restoration of skilled locomotor movements. I discuss how this approach is now being applied to a C4 contusion rat model.

关键词： corticospinal tract motor cortex electrical stimulation spinal direct current stimulation spinalcord injury brain injury

Boosting corticospinal system synaptic plasticity to recover motor functions

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Neural Regeneration Research 2023年第10期18卷 2182-2183页

作者： Weiguo Song john h.Martin Feinstein Institutes for Medical Research ManhassetNYUSA Department of Molecular Cellularand Biomedical SciencesCenter for Discovery and Innovation Neuroscience Program Graduate Center of the City University of New YorkNew YorkNYUSA

An importa nt strategy to promote voluntary movements after motor system injury is to strengthen the connections between the motor cortex and muscles by taking advantage of the plasticity of the corticospinal motor *** neuromodulation approaches are directed to activate the spinal cord and peripheral axons to strengthen muscle *** discuss in this perspective that,the cortex and spinal cord should be ta rgeted together to enhance cortex-to-musclefunction(Amer and Martin,2022).

关键词： plasticity system activation

Statistical testing and distribution for lead chloride toxicity

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Asian Journal of Andrology 2005年第1期7卷 107-108,页

作者： john h.Lange Envirosafe Training and Consultants P.O. Box 114022 Pittsburgh PA 15239 USA

Dear Sir, Graca et al.[1]provided an interesting investigationon the toxicity of lead chloride and sperm developmentin ***, I would like to make a comment onthe statistical analysis *** 1 and its resultsSuggest that a... 详细信息

关键词： Animals Biomedical Research Comparative Study Lead Male Mice Spermatogenesis

Eyes and stroke:the visual aspects of cerebrovascular disease

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Stroke & Vascular Neurology 2017年第4期2卷 211-221页

作者： john h Pula Carlen A Yuen Department of Neurology NorthShore University HealthSystemChicagoIllinoisUSA Department of Neurology University of ChicagoChicagoIllinoisUSA

A large portion of the central nervous system is dedicated to vision and therefore strokes have a high likelihood of involving vision in some *** loss can be the most disabling residual effect after a cerebral *** vision problems can likewise be a harbinger of stroke and prompt evaluation after recognition of visual symptoms can prevent future vascular *** this review,we discuss the visual aspects of ***,anatomy and the vascular supply of the visual system are ***,the different stroke syndromes which involve vision are ***,topics involving the assessment,prognosis,treatment and therapeutic intervention of vision-specific stroke topics are reviewed.

关键词： anatomy ed. visual

Protein folding, protein homeostasis,and cancer

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Chinese Journal of Cancer 2011年第2期30卷 124-137页

作者： john h. Van Drie Van Drie Research

Proteins fold into their functional 3-dimensional structures from a linear amino acid sequence. In vitro this process is spontaneous; while in vivo it is orchestrated by a specialized set of proteins, called chaperones. Protein folding is an ongoing cellular process, as cellular proteins constantly undergo synthesis and degradation. here emerging links between this process and cancer are reviewed. This perspective both yields insights into the current struggle to develop novel cancer chemotherapeutics and has implications for future chemotherapy discovery.

关键词：蛋白质折叠蛋白质平衡癌症化疗药物氨基酸序列三维结构蛋白合成细胞

Crack-free high-aspect ratio holes in glasses by top–down percussion drilling with infrared femtosecond laser Ghz-bursts

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International Journal of Extreme Manufacturing 2023年第1期5卷 193-200页

作者： Pierre Balage john Lopez Guillaume Bonamis Clemens hönninger Inka Manek-hönninger Universitéde Bordeaux-CNRS-CEA CELIA UMR 510733405 TalenceFrance Amplitude Citéde la Photonique11 Avenue de Canteranne33600 PessacFrance

We report novel results on top-down percussion drilling in different glasses with femtosecond laser *** to this particular regime of light–matter interaction,combining non-linear absorption and thermal cumulative effects,we obtained crack-free holes of aspect ratios exceeding 30 in sodalime and 70 in fused *** results are discussed in terms of inner wall morphology,aspect ratio and drilling speed.

关键词： femtosecond laser glass Ghz-bursts percussion drilling