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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.

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

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

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

An efficient method for computing excess free energy of liquid

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Science China Chemistry 2018年第1期61卷 135-140页

作者： Jianing Song Linqiong Qiu john Z.h. Zhang School of Chemistry and Molecular Engineering East China Normal University Shanghai 200062 China NYU-ECNU Center for Computational Chemistry at NYU ShanghaL Shanghai 200062 China State Key Laboratory of Precision Spectroscopy East China Normal University Shanghai 200062 China Department of Chemistry New York University NY NY 10003 USA

We present a new theoretical method for efficient calculation of free energy of liquid. This interaction entropy method allows one to compute entropy and free energy of liquid from standard single step MD(molecular dynamics) simulation directly in liquid state without the need to perform MD simulations at many intermediate states as required in thermodynamic integration or free energy perturbation methods. In this new approach, one only needs to evaluate the interaction energy of a single(fixed) liquid molecule with the rest of liquid molecules as a function of time from a standard MD simulation of liquid and the fluctuation of distribution of this interaction energy is then used to calculate the interaction entropy of the liquid. Explicit theoretical derivation of this interaction entropy approach is provided and numerical calculations for the benchmark liquid water system were carried out using three different water models. Numerical analysis of the result was performed and comparison of the computational result with experimental data and other theoretical results were provided. Excellent agreement of calculated free energies with the experimental data using TIP4 P model is obtained for liquid water.

关键词： excess free energy liquid MD simulation interaction entropy

STUDYING COMPLEX ADAPTIVE SYSTEMS

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Journal of Systems Science & Complexity 2006年第1期19卷 1-8页

作者： john h.holland Department of Electrical Engineering and Computer Science.College of Engineering.University of Michigan 1301 Beal Avenue Ann ArborMichigan 48109-2122.USA.

Complex adaptive systems （cas） - systems that involve many components that adapt or learn as they interact - are at the heart of important contemporary problems. The study of cas poses unique challenges： Some of our most powerful muthemutical tools, particularly methods involivng fixed points, attractors, and the like, are of limited help in understanding the development of cas. This paper suggests ways to modify research methods and tools, with an emphasis on the role of computer-based models, to increase our understanding of cas.

关键词： Agent-based systems classifier systems complex adaptive systems computer-based models credit assignlnent genetic algorithms parallelism rule discovery signal-passing tags.

Focal therapy for localized prostate cancer:is there a “middle ground” between active surveillance and definitive treatment?

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Asian Journal of Andrology 2019年第1期21卷 37-44页

作者： Cihan h Demirel Muammer Altok john W Davis Department of Urology The University of Texas MD Anderson Cancer CenterHoustonTexas 77030USA.

In recent years,it has come a long way in the diagnosis,treatment,and follow-up of prostate *** this,it was argued that definitive treatments could cause overtreatment,particularly in the very low,low,and favorable risk *** alternative treatment and follow-up methods are being considered for this group of patients,active surveillance is seen as a good alternative for patients with very low and low-risk groups in this ***,it has become necessary to find other alternatives for patients in the favorable risk group or patients who cannot adopt active *** the light of technological developments,the concept of focal therapy was introduced with the intensification of research to treat only the lesioned area instead of treating the entire organ for prostate lesions though there are not many publications about many of them *** to the initial results,it was understood that the results could be good if the appropriate focal therapy technique was applied to the appropriate ***,focal therapies have begun to find their"middle ground"place between definitive therapies and active follow-up.

关键词： focal therapy multiparametric magnetic resonance imaging prostate biopsy prostate cancer prostatic neoplasms

Simulation of multiple scattering of seismic waves by spatially distributed inclusions

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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.

Isotretinoin for the treatment of nonobstructive azoospermia: a pilot study

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Asian Journal of Andrology 2021年第5期23卷 537-540页

作者： john K Amory Charles h Muller Thomas J Walsh Department of Medicine University of WashingtonSeattleWA 98195USA Department of Urology University of WashingtonSeattleWA 98195USA

The treatment of men with infertility from azoospermia is *** some men with severe oligozoospermia improve sperm output during treatment with isotretinoin,we treated nine men with azoospermia with isotretinoin to determine if azoospermic men would also respond to isotretinoin *** of these men who had a previous negative testicular sperm extraction(TESE)was found to have an area of sperm production on a postisotretinoin testicular *** man achieved a pregnancy and a live birth of a healthy,term daughter after in vitro fertilization coupled with intracytoplasmic sperm injection(IVF/ICSI).A second subject had a positive TESE after treatment as *** study of isotretinoin therapy in men with azoospermia undergoing testicular sperm harvesting procedures is warranted.

关键词： treatment injection pregnancy