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Experimental study of channel delay impact on throughput performance of TCP and its extensions in space

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第10期6卷 1015-1020页

作者： wang Ru-fa wang Ru h. School of Computer Science Gansu Institute of Political Science and Law Lanzhou 730070 China Department of Electrical Engineering. Lamar University Beaumont TX 77710-1829 USA

Substantially long round trip time (RTT) in space channel hurts TCP interactions between the sending and receiving ends, and limits the usefulness and effectiveness of TCP feedback. Space Communication Protocol Standards-Transport Protocol (SCPS-TP) is a Transmission Control Protocol (TCP) enhancement method aimed at improving its performance in space and interplanetary Internet and is expected to have capability of being feasible applied to experimental evaluation of the effectiveness of SCPS-TP in coping with long channel delay. This paper presents an experimental evaluation of channel delay impact on throughput performance of SCPS-TP over LEO/GEO-stationary space links using a test-bed, compared with the widely deployed TCP.

关键词： Intemet protocols Satellite communication Channel delay TCP SCPS-TP

Increased salt sensitivity induced by sensory denervation: role of superoxide

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Acta Pharmacologica Sinica 2004年第12期25卷 60-66页

作者： Alex F ChEN,Donna h wang Department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA Department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA

AIM: To test the hypothesis that production of superoxide in mesenteric resistance arteries is increased and con- tributes to the development of hypertension induced by sensory denervation plus high salt intake. METhODS: Newborn Wistar rats were given capsaicin 50 mg/kg sc on the 1st and 2nd d of life. After weaning, male rats were grouped as follows and treated for 3 weeks with: capsaicin pretreatment plus normal sodium diet (0.5 %, CAP-NS), CAP plus high sodium diet (4 %, CAP-hS), control plus NS (CON-NS), or CON-hS. Both tail-cuff systolic blood pressure and mean arterial pressure (MAP) were measured in each of the groups. Western blot analysis was used for measurement of manganese superoxide dismutase (MnSOD) and endothelial nitric oxide synthase (eNOS) in the mesenteric resistance arteries. Lucigenin chemiluminescence assay was used for superoxide production in the mesenteric resistance arteries. The Griess method was used for measurement of nitrite/nitrate levels in plasma. RESULTS: Both tail-cuff pressure and MAP were higher in CAP-hS compared with CAP-NS, CON-hS, and CON- NS rats (Ph MnSOD and eNOS in the mesenteric resistance arteries were increased in CAP-hS compared with CAP-NS, CON-hS, and CON-NS (Phowever, nitrite/nitrate levels in plasma were not different among 4 groups. Acute iv administration of tempol, a membrane-permeable superoxide scavenger, de- creased MAP in both CAP-hS and CON-hS when compared with their respective controls. however, the de- creases of MAP between these two groups were not different. Chronic treatment with tempol failed to prevent the development of hypertension in CAP-hS rats. Superoxideproduction in the mesenteric resistance arteries was increased in CAP-hS compared with CAP-NS, CON-hS, and CON-NS (Phowever, chronic treatment with tempol did not prevent the increase of mesenteric superoxideproduction in CAP-hS rats. CONCLUSIONS: Regardless of increased vascular MnSOD levels, salt

关键词： superoxides tempol afferent neurons capsaicin denervation dietary sodium chloride nitric oxide

Stochastic Distribution Control of Singular Systems: Output PDF Shaping

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自动化学报 2005年第1期31卷 151-160页

作者： h.YUE A.J.A.LEPRAND h.wang InstituteofAutomation ChineseAcademyofSciencesBeijing100080P.R.China ControlSystemsCentre TheUniversityofManchesterManchesterM601QDUK instituteofAutomation ChineseAcademyofSciencesBeijing100080P.R.China／／ControlSystemsCentreTheUniversityofManchesterManchesterM601QDUK

This paper presents a new algorithm designed to control the shape of the output probability density function (PDF) of singular systems subjected to non-Gaussian input. The aim is to select a control input uk such that the output PDF is made as close as possible to a given *** on the B-spline neural network approximation of the output PDF, the control algorithm is formulated by extending the developed PDF control strategies of non-singular systems to singular systems. It has been shown that under certain conditions the stability of the closed-loop system can be guaranteed. Simulation examples are given to show the effectiveness of the proposed control algorithm.

关键词：随机分布控制单系统 PDF显示输出动态随机系统概率密度函数

Superconducting fluctuation induced conductance corrections near a pair-breaking quantum phase transition in doubly connected ultrathin cylinders of Al

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Science China(Physics,Mechanics & Astronomy) 2020年第3期63卷 89-97页

作者： Ke Zhang ZongLi wang Da Xu YaZhe wang h.wang Ying Liu Department of Physics Zhejiang UniversityHangzhou 310027China Key Laboratory of Artificial Structures and Quantum Control(MOE)and Shanghai Center for Complex Physics School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Materials Research Institute and Department of Physics Pennsylvania State UniversityUniversity ParkPA 16802USA Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

We report measurements on ultrathin,doubly connected superconducting cylinders of Al that exhibit a destructive regime,which refers to the loss of superconductivity in a doubly connected superconductor near applied half flux quanta due to the sample topology and the small size of the sample.A depairing quantum phase transition(QPT)between a superconducting and metallic state tuned by the magnetic flux enclosed in the quasi one-dimensional(1D)cylinder was found at the onset of the destructive *** on magnetic flux and temperature dependent sample resistance as well as current-voltage characteristics revealed the presence of both thermally activated and quantum phase slips near the depairing *** the superconducting side of the QPT,thermally activated phase slips as described by the Langer-Ambegaokar and McCumber-halperin(LAMh)theory were found to describe the sample resistance as the system was pushed towards the QPT by a magnetic field applied along the cylinder ***,deviation from this behavior was found at low temperatures,signaling the presence of the quantum phase *** importantly,we observed a highly unusual negative slope in the resistance versus temperature curves on the metallic side of the QPT as predicted by the diagrammatic calculation of the dc conductivities in a 1D system near a depairing *** work suggests that fluctuations from both the phase and the amplitude of the superconducting order parameter are important for the superconductor-to-metal depairing QPT.

关键词： mesoscopic superconductor quantum phase transition superconducting fluctuation

A MAThEMATICAL MODEL FOR ThE STABILITY OF ThEhYDRIDES OF Ca CONTAINING RNi_5 COMPOUNDS

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Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 116-120页

作者： X.h.wang Zhejiang Univ Hangzhou China

In this paper, a mathematical model for the stability of hydrides of Ca containing compounds was proposed on the basis of introducing the geometrical and electric factors. The data on (R, Ca)Ni5 compounds are in good agreement with the theoretical curve obtained from the model. For Ml1-x CaxNi5 compounds, the variation of dissociation pressure with cell volume is the joint effects of geometrical and electric factors, and the controlling factor changes gradually from geometrical factor to electric factor with increasing x.

关键词： hydride hydrogen storage alloy intermetallic compound rare earth

The synergetic effects of two CCAAT boxes in Aspergillus niger glaA gene promoter on activation of PglaA transcription

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Science China(Life Sciences) 2004年第2期47卷 139-147页

作者： wang h. M. Genencor International Inc. 925 Page Mill Road Palo Alto California 94304 USA

EMSA and footprinting analyses have revealed that the -489—-414 bp and the -390—-345 bp (designated DC and PC respectively) upstream of the Aspergillus niger T21 glaA gene were bound by one protein factor in the A. niger T21 whole cell extract. Both DC and PC contained CCAAT pentanucleotides. The functions of DC and PC in regulation of expression of glucoamylase (GLA) were studied. CCAAT pentanucleotides were replaced with CGTAA and the mutated DNA fragments DCm and PCm lost the binding activities of protein factors in vitro. In vivo when either DC or PC was mutated or the relative orientations between them were changed on the PglaA, the transcriptional activity of PglaA decreased to a basal level. Introduction of multi-copies of DC into the original site at the PglaA in A. niger T21 decreased the expression of endogenous GLA expression and the exogenous reporter E. coli uidA gene introduced under the PglaA promoter, while having no effect on the uidA gene under the control of PgpdA. EMSA re-vealed that the levels of the specific DNA-binding protein factors in the transformants maintained the same meaning that introduction of multi-copies of DC caused the titration effect. AnghapC gene was cloned from A. niger T21 cDNA and introduced into the DC multi-copied strains. The expression of AnghapC improved the expression of the endogenous GLA and the exogenous gene controlled by PglaA. These results showed that both the CCAAT pentanucleotides were necessary for DC and PC binding to the protein factors, and the simultaneous binding of DC and PC to the protein was necessary for promoting the transcriptional activity of PglaA. AnghapC was the specific positive trans-acting protein factor binding to DC.

关键词： Aspergillus niger glucoamylase, synergetic effect, mutation analysis, multi-copy of CCAAT box, titration effect.

Generation and repair of AID-initiated DNA lesions in B lymphocytes

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Frontiers of Medicine 2014年第2期8卷 201-216页

作者： Zhangguo Chen Jing h. wang Integrated Department of Immunology University of Colorado Anschutz Medical Campus and National Jewish Health Denver CO 80206USA

Activation-induced deaminase （AID） initiates the secondary antibody diversification process in B lymphocytes. In mammalian B cells, this process includes somatic hypermutation （ShM） and class switch recombination （CSR）, both of which require AID. AID induces U：G mismatch lesions in DNA that are subsequently converted into point mutations or DNA double stranded breaks during ShM/CSR. In a physiological context, AID targets immunogiobulin （Ig） loci to mediate ShM/CSR. however, recent studies reveal genome-wide access of AID to numerous non-Ig loci. Thus, AID poses a threat to the genome of B cells if AID-initiated DNA lesions cannot be properly repaired. In this review, we focus on the molecular mechanisms that regulate the specificity of AID targeting and the repair pathways responsible for processing AID-initiated DNA lesions.

关键词： class switch recombination somatic hypermutation activation-induced deaminase DNA repair genomic instability

Layered Machinable and Electrically Conductive Ti_2AlC and Ti_3AlC_2 Ceramics:a Review

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Journal of Materials Science & Technology 2010年第5期26卷 385-416页

作者： X.h. wang Y.C. Zhou Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang110016 China

Ti2AlC and Ti3AlC2 are the most light-weight and oxidation resistant layered ternary carbides belonging to the MAX *** review highlights recent achievements on the processing,microstructure,physical,mechanical and chemical properties of these two machinable and electrically conductive ***2AlC and Ti3AlC2 display superior properties such as fracture toughness,electrical and thermal conductivities,and oxidation resistance over their binary *** paper provides a comprehensive overview of the processing-microstructure-property correlations of these two *** fields of applications for Ti2AlC and Ti3AlC2 are *** addition,we point out methods for further improving their properties in some specific applications through appropriate structural design and modification.

关键词： MAX phases Ti2AlC Ti3AlC2 Machinable ceramics

Flux focusing with a superconducting nanoneedle for scanning SQUID susceptometry

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Microsystems & Nanoengineering 2023年第3期9卷 411-417页

作者： B.K.Xiang S.Y.wang Y.F.wang J.J.Zhu h.T.Xu Y.h.wang State Key Laboratory of Surface Physics and Department of Physics FudanUniversity200433 ShanghaiChina Shanghai Research Center for Quantum Sciences 201315 ShanghaiChina

A nanofabricated superconducting quantum interference device(nano-SQUID)is a direct and sensitive flux probe used for magnetic imaging of quantum materials and mesoscopic *** to the functionalities of superconductive integrated circuits,nano-SQUIDs fabricated on chips are particularly versatile,but their spatial resolution has been limited by their planar ***,we use femtosecond laser 3-dimensional(3D)lithography to print a needle onto a nano-SQUID susceptometer to overcome the limits of the planar *** nanoneedle coated with a superconducting shell focused the flux from both the field coil and the *** performed scanning imaging with such a needle-on-SQUID(NoS)device on superconducting test patterns with topographic *** NoS showed improved spatial resolution in both magnetometry and susceptometry relative to the planarized *** work serves as a proof-of-principle for integration and inductive coupling between superconducting 3D nanostructures and on-chip Josephson nanodevices.

关键词： lithography SQUID needle