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Science China Earth Sciences 2011年第12期54卷 1830-1844页

作者： WHANG Y. C catholic university of america

Interaction of the solar wind with the interstellar medium leads to the formation of the heliosphere and termination shock. This article addresses three aspects of the plasma and magnetic field on two sides of the heliopause：（1） The interstellar magnetic field surrounding the heliopause. In the limit of very low plasma β-ratio an analytical solution is obtained for the 3D interstellar magnetic field by means of a line dipole method. The undisturbed magnetic field in the upstream is allowed to have an arbitrary inclination angle. The solution describes the heliosphere as having a blunt-nosed geometry on the upwind side and approaching a cylindrical geometry on the downwind side. The distortion of the magnetic field can penetrate very deep into the interstellar space. （2） Interaction of the interstellar neutral hydrogen with the global solar wind. The ionization process leads to removal of interstellar neutral hydrogen in the heliosphere： on the upwind side, 90% of hydrogen depletion occurs inside 60 AU, the hydrogen density changes rapidly inside 10 AU. A hydrogen cavity forms inside -4 AU; the cavity extends on the downwind side to form a long cavity wake. Outside the cavity and cavity wake, pickup protons are produced, they cause deceleration and heating of the solar wind. The wind speed and temperature also increase steadily with heliolatitude caused by the latitudinal increase in wind speed at the inner boundary. （3） The global geometry of the termination shock. The termination shock has been treated as having a closed geometry in previous heliosphere models. This study presents a new perspective that the global termination shock may have a bow-shaped open geometry. The termination shock forms on the upwind side because the forward motion of the supersonic solar wind is blocked at the blunt-nosed heliopause. However, the heliopause likely to be open on the downwind side; the motion of the supersonic solar wind is unobstructed for shock formation. Thus, the globa

关键词： solar wind interstellar medium magnetic fields plasmas magnetohydrodynamics (MHD)

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Alcohol-induced alterations of the hepatocyte cytoskeleton

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World Journal of Gastroenterology 2010年第11期16卷 1358-1365页

作者： Blythe D Shepard Pamela L Tuma Department of Biology The Catholic University of America

The hepatocyte cytoskeleton consists of three fi lamentous networks: microtubules, actin microfi laments and keratin intermediate filaments. Because of the abundance of the proteins that comprise each system and the central role each network plays in a variety of cellular processes, the three fi lament systems have been the focus of a host of studies aimed at understanding the progression of alcohol-induced liver injury. In this review, we will briefly discuss the hepatic organization of each cytoskeletal network and highlight some components of each system. We will also describe what is known about ethanol-induced changes in the dynamics and distributions of each cytoskeletal system and discuss what is known about changes in protein expression levels and post-translational modifi cations. Finally, we will describe the possible consequences of these cytoskeletal alterations on hepatocyte function and how they might contribute to the progression of liver disease.

关键词： Ethanol Hepatotoxicity Tubulin Actin Keratin

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RADIATIVE TRANSPORT IN THE DELTA-P1 APPROXIMATION FOR LAMINAR OPTICAL TOMOGRAPHY

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Journal of Innovative Optical Health Sciences 2009年第2期2卷 149-163页

作者： BAOHONG YUAN Department of Biomedical Engineering catholic university of america Washington DC 20064 USA

To provide a computational efficient forward model with moderate accuracy for rapid 3D optical tomography in small volumes,radiative transport in the delta-P1 approximation combined with the approximation of the reciprocity was *** of optical signals caused by absorption and fluorescence heterogeneities submerged in a resin-based liquid phantom with background parameters close to rat brain tissues were measured using a recently constructed laminar optical tomography *** measured perturbations were used to examine the theoretically calculated fluence perturbations based on the delta-P1 approximation and the reciprocity *** show that the errors between the predicted and measured data are acceptable,especially for fluorescence perturbations.

关键词： Photon migration tomography fluorescence delta-P1 approximation reciprocity approximation.

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On the Performance of the Energy Detector Subject to Impulsive Noise in κ-μ, α-μ, and η-μ Fading Channels

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Tsinghua Science and Technology 2017年第4期22卷 360-367页

作者： Jos V.M.Cardoso Wamberto J.L.Queiroz Hang Liu Marcelo S.Alencar Department of Electrical Engineering Federal University of Campina Grande Department of Electrical Engineering and Computer Science The Catholic University of America

This paper presents a unified theoretical analysis of the energy detection of Gaussian and M-PSK signals in κ-μ,α-μ,and η-μ fading channels at the output of an energy detector subject to impulsive noise（Bernoulli-Gaussian model）. As a result, novel, simple, and accurately approximated expressions for the probability of detection are derived. More precisely, the generalized Gauss-Laguerre quadrature is applied to approximate the probability of detection as a simple finite sum. Monte Carlo simulations corroborate the accuracy and precision of the derived approximations. The results are further extended to cooperative energy detection with hard decision combining information.

关键词： spectrum sensing energy detector fading channel impulsive noise

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Alcohol-induced protein hyperacetylation: Mechanisms and consequences

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World Journal of Gastroenterology 2009年第10期15卷 1219-1230页

作者： Blythe D Shepard Pamela L Tuma Department of Biology The Catholic University of America 620 Michigan Avenue NE Washington DC 20064 United States

Although the clinical manifestations of alcoholic liver disease are well-described, little is known about the molecular basis of liver injury. Recent studies have indicated that ethanol exposure induces global protein hyperacetylationo This reversible, post- translational modification on the E-amino groups of lysine residues has been shown to modulate multiple, diverse cellular processes ranging from transcriptional activation to microtubule stability. Thus, alcohol- induced protein hyperacetylation likely leads to major physiological consequences that contribute to alcohol-induced hepatotoxicity. Lysine acetylation is controlled by the activities of two opposing enzymes, histone acetyltransferases and histone deacetylases. Currently, efforts are aimed at determining which enzymes are responsible for the increased acetylation of specific substrates. However, the greater challenge will be to determine the physiological ramifications of protein hyperacetylation and how they might contribute to the progression of liver disease. In this review, we will first list and discuss the proteins known to be hyperacetylated in the presence of ethanol. We will then describe what is known about the mechanisms leading to increased protein acetylation and how hyperacetylation may perturb hepatic function.

关键词： Ethanol Hepatotoxicity Acetylation Deacetylases Acetyltransferases

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Hsa-miR-214-3p inhibits breast cancer cell growth and improves the tumor immune microenvironment by downregulating B7H3

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Oncology Research 2025年第1期33卷 103-121页

作者： YAN LU KANG WANG YUANHONG PENG MENG CHEN LIN ZHONG LUJI HUANG FU CHENG XINDAN SHENG XIN YANG MANZHAO OUYANG GEORGE A.CALIN ZHIWEI HE China-america Cancer Research Institute Guangdong Medical UniversityDongguan523808China GCP Center Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China Department of Gastrointestinal Surgery Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou510080China Department of Translational Molecular Pathology The University of Texas MD Anderson Cancer CenterHoustonTX 77030USA Department of Oncology Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)Shunde528300China

Background:Immune checkpoint inhibitors play an important role in the treatment of solid tumors,but the currently used immune checkpoint inhibitors targeting programmed cell death-1(PD-1),programmed cell death ligand-1(PD-L1),and cytotoxic T-lymphocyte antigen-4(CTLA-4)show limited clinical efficacy in many breast cancers.B7H3 has been widely reported as an immunosuppressive molecule,but its immunological function in breast cancer patients remains ***:We analyzed the expression of B7H3 in breast cancer samples using data from the Cancer Genome Atlas Program(TCGA)and the Gene Expression Omnibus(GEO)*** were selected using the TarBase,miRTarBase,and miRBase *** regulatory role of the microRNA hsa-miR-214-3p on B7H3 was investigated through dual-luciferase reporter assays,which identified the specific action sites of *** expression levels of B7H3 and hsa-miR-214-3p in human breast cancer tissues and adjacent normal tissues were quantified using Western blotting and quantitative PCR(qPCR).In vitro experiments were performed to observe the effects of modulating the expression of B7H3 or hsa-miR-214-3p on breast cancer cell proliferation and ***,the regulatory impact of hsa-miR-214-3p on B7H3 was ***-linked immunosorbent assays(ELISA)and flow cytometry were employed to assess the effects of co-cultured breast cancer cells and normal human peripheral blood mononuclear cells(PBMCs)on immune cells and associated ***:In breast cancer tissues,the expression level of B7H3 is inversely correlated with that of hsa-miR-214-3p,as well as with the regulatory effects on breast cancercell ***-miR-214-3p was found to inhibit breast cancer cell growth by downregulating ***,our research identified,for the first time,two binding sites for hsa-miR-214-3p on the 3’UTR of B7H3,both of which exert similar effects ***-culture experiments revealed that hsamiR-214-3p

关键词： Breast cancer B7H3 Hsa-miR-214-3p Immunotherapy

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Transient response of a beam on viscoelastic foundation under an impact load during nondestructive testing

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Earthquake Engineering and Engineering Vibration 2005年第2期4卷 325-333页

作者：孙璐罗飞全陈东晖 Department of Civil Engineering Catholic University of America620 Michigan Ave.N.E.Washington DC.20064USA AssistantProfessor Department of Civil Engineering Catholic University of America620 Michigan Ave.N.E.Washington DC.20064USA Graduate Student

Beam responses under an impact NDT load are studied using the Fourier and Laplace transforms. Numerical computation is performed for a parametric study of beam and load parameters. It is shown that under an impact load, the time duration for displacement to vanish is ten times longer than that for velocity and acceleration. The maximum response is achieved first in acceleration, followed by velocity, and finally displacement, all of which occur before the impact load is removed. At the moment that the impact load is removed from the beam, there is a discontinuity in the velocity and acceleration responses, but not in displacement response. The effect of K and ph on beam response is much less significant than that of EI and C, which have similar effect on beam response. As El increases, peak values of displacement, velocity and acceleration response decrease, The effect of K on beam response only becomes appreciable after the impact load is removed. While the peak of displacement remain almost unchanged large K values than for small K values. as K increases, the displacement response decays to zero faster for

关键词： beam acceleration impact load Laplace transform Fourier transform

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碳纳米管纱在应力下的压阻效应:现象和影响因素(英文)

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新型炭材料 2018年第2期33卷 140-154页

作者： Jude C.Anike Kalayu Belay Jandro L.Abot Department of Mechanical Engineering The Catholic University of America Department of Physics Florida A&M University

碳纳米管因机械应力敏感特性而成为传感器的理想材料。单原子层厚度的石墨烯片卷曲而成的单壁碳纳米管具有大约1 nm的管径。碳纳米管纺丝形成纱,使其能够用于结构组份中。本文研究了碳纳米管纱的几何尺寸、力学性能和准静态应力加载速... 详细信息

碳纳米管因机械应力敏感特性而成为传感器的理想材料。单原子层厚度的石墨烯片卷曲而成的单壁碳纳米管具有大约1 nm的管径。碳纳米管纺丝形成纱,使其能够用于结构组份中。本文研究了碳纳米管纱的几何尺寸、力学性能和准静态应力加载速率对其压阻效应的影响。应力加载速率影响碳纳米管纱的失效机理和机电特性。高应力加载速率导致拉伸强度的增加和正压阻效应,而低应力加载速率引起较高的应力失效与负压阻效应。碳纳米管纱的压阻传感器系数随应力加载速率基本不变,但其对于应力水平和碳纳米管纱的几何尺寸具有高度依赖性。作为传感器所需的线性压阻关系在高应力加载速率下相关系数为0.995,而在低应力加载速率下相关系数只有0.832。

关键词：压阻效应碳纳米管传感器

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VARIATIONS OF INTERPLANETARY FLUCTUATIONS ACROSS THE BOW SHOCK

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Science China Mathematics 1988年第10期31卷 1240-1254页

作者：魏奉思都亨黄云潮 Beijing Washington D. C. USA Institute of Space Physics Department of Mechanical Engineering the catholic university of america Scientia Sinica

Shell’s transmission model of an MHD wave through a fast shock is not to treat transmission of waves beyond the critical incident angles. Considering that interplanetary fluctuations impinge on the bow shock from all directions, a model studying the interaction between MHD waves and the Earth’s bow shock under ordinary conditions is presented in this paper. The results show that the state of fluctuations undergoes a siginificant jump across the Earth’s bow shock. Both the amplitude of fluctuations and the degree of fluctuation anisotropy increase across the Earth’s bow shock. The calculated probability distribution functions of fluctuations immediately behind the bow shock is very similar to those reconstructed from the observed magnetosheath data. Simulations for the spatial variation in the state of fluctuations behind the bow shock reveal that the fluctuation activities display the dawn-dusk asymmetry higher in the dawn side than in the dusk side. When interplanetary background magnetic field lies in

关键词： interplanetary fluctuation bow shock.

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A new beam asymmetry measurement from pion photoproduction on the neutron using CLAS

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Chinese Physics C 2009年第12期33卷 1369-1372页

作者： D. Sokhan D. Watts F. Klein School of Physics & Astronomy University of Edinburgh Edinburgh EH9 3JZ UK Department of Physics Catholic University of America Washington DC 20064 USA

We present a preliminary analysis of the photon beam asymmetry observable （Z） from the pho- toproduction reaction channel γn → pπ in the invariant mass range 1.6--2.3 GeV. The measurement was obtained using the near-4π CEBAF Large Acceptance Spectrometer （CLAS） at Jefferson Laboratory, USA, employing a linearly polarised photon beam with an energy range 1.1 2.3 GeV, incident on a liquid deuterium target. The measurement will provide new data to address the poorly established neutron excitation spectrum and will greatly expand the sparse world data-set both in energy and angle.

关键词： beam asymmetry photonuclear photoproduction neutron pion.

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