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Measurement of J/ψ leptonic width with the KEDR detector

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Chinese Physics C 2010年第6期34卷 836-841页

作者： A.g.Shamov Budker Institute of Nuclear Physics

We report a new precise determination of the leptonic widths of the J/psi meson performed with the KEDR detector at the VEPP-4M e^＋e^- collider. The measured values of the J/psi parameters are： Гee×Гee/P = 0.3323±0.0064 （stat.）±0.0048 （syst.） keV,Гee×Гμμ/Г = 0.3318±0.0052 （stat.） ±0.0063 （syst.） keY. Assuming eμ universality and using the table value of the branching ratios the leptonic Г11 = 5.59 ± 0.12 keV width and the total Г = 94.1±2.7 keV widths were obtained. We also discuss in detail a method to calculate radiative corrections at a narrow resonance.

关键词： J/ψ meson lepton width full width

Electrical Characteristics of Co/n-Si Schottky Barrier Diodes Using I -- V and C -- V Measurements

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Chinese Physics Letters 2009年第6期26卷 254-257页

作者： g. güler OE. güllü S. Karatas OE. F. Bakkaloglu Department of Physics Faculty of Education University of Adiyaman 02100 Adiyaman Tarkey Department of Physics Faculty of Sciences and Arts University of Barman 72060 Barman Turkey Department of Physics Faculty of Sciences and Arts University of Kahramanmaras Sütcü imam 46100 Kahramanmaras Turkey Department of Engineering Physics Faculty of Engineering Physics University of Gaziantep 27310 Gaziantep Turkey

Electrical characteristics of Co/n-Si Schottky barrier diodes are analysed by current- voltage （I- V） and capacitancevoltage （C- V） techniques at room temperature. The electronic parameters such as ideality factor, barrier height and average series resistance are determined. The barrier height 0. 76 eV obtained from the C - V measurements is higher than that of the value 0. 70 eV obtained from the I - V measurements. The series resistance Rs and the ideality factor n are determined from the d ln（ I） /dV plot and are found to be 193.62 Ω and 1.34, respectively. The barrier height and the Rs value are calculated from the H（I） - I plot and are found to be 0.71 eV and 205.95Ω. Furthermore, the energy distribution of the interface state density is determined from the forward bias I - V characteristics by taking into account the bias dependence of the effective barrier height. The interface state density Nss ranges from 6.484×10^11 cm^-2eV^-1 in （Ec - 0.446） eV to 2.801×10^10 cm^-2eV^-1 in （Ec - 0.631） eV, of the Co/n-Si Schottky barrier diode. The results show the presence of a thin interracial layer between the metal and the semiconductor.

关键词： No English Keywords

Pro-resolving lipid mediator reduces amyloid-β42–induced gene expression in human monocyte–derived microglia

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Neural Regeneration Research 2025年第3期20卷 873-886页

作者： Ying Wang Xiang Zhang Henrik Biverstål Nicolas gBazan Shuai Tan Nailin Li Makiko Ohshima Marianne Schultzberg Xiaofei Li Department of Neurobiology Care Sciences&SocietyDivision of NeurogeriatricsKarolinska InstitutetStockholmSweden Department of Neurology Neuroscience CenterThe First Hospital of Jilin UniversityChangchunJilin ProvinceChina Department of Physiology and Pharmacology Karolinska InstitutetStockholmSweden Department of Biosciences and Nutrition Karolinska InstitutetHuddingeSweden Neuroscience Center of Excellence Louisiana State UniversityNew OrleansLAUSA Department of Medicine SolnaClinical Pharmacology GroupKarolinska University HospitalStockholmSweden

Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment of Alzheimer's disease to prevent/stop inflammation and combat disease pathology. Therefore, it is important to clarify whether they counteract the expression of genes and proteins induced by amyloid-β. With this objective, we analyzed the relevance of human monocyte–derived microglia for in vitro modeling of neuroinflammation and its resolution in the context of Alzheimer's disease and investigated the pro-resolving bioactivity of maresin 1 on amyloid-β42–induced Alzheimer's disease–like inflammation. Analysis of RNA-sequencing data and secreted proteins in supernatants from the monocyte-derived microglia showed that the monocyte-derived microglia resembled Alzheimer's disease–like neuroinflammation in human brain microglia after incubation with amyloid-β42. Maresin 1 restored homeostasis by down-regulating inflammatory pathway related gene expression induced by amyloid-β42 in monocyte-derived microglia, protection of maresin 1 against the effects of amyloid-β42 is mediated by a re-balancing of inflammatory transcriptional networks in which modulation of gene transcription in the nuclear factor-kappa B pathway plays a major part. We pinpointed molecular targets that are associated with both neuroinflammation in Alzheimer's disease and therapeutic targets by maresin 1. In conclusion, monocyte-derived microglia represent a relevant in vitro microglial model for studies on Alzheimer's disease-like inflammation and drug response for individual patients. Maresin 1 ameliorates amyloid-β42–induced changes in several genes of importance in Alzheimer's disease, highlighting its potential as a therapeutic target for Alzheimer's disease.

关键词： Alzheimer's disease amyloid-β maresin microglia monocyte neuroinflammation resolution RNA-sequencing specialized pro-resolving lipid mediator

SIMULATION OF 3-D DEFORMATION AND MATERIAL FLOW DURINg ROLL FORgINg PROCESS USINg SYSTEM OF OVAL-ROUND gROOVE

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Acta Metallurgica Sinica(English Letters) 2007年第5期20卷 380-384页

作者： g.H. Liu g.S. Ren C.g. Xu Beijing Research Institute of Mechanical ＆ Electrical Technology Beijing 100083 China Huazhong University of Science and Technology Wuhan 430074 China

Basing on the analysis of the traits of the roll forging process, a system-model of computer simulation has been established. Three-dimensional rigid-plastic FEM has been used for the simulation of the deformation process in the oval and round pass rolling, including the entering, rolling, and separating stages. The analysis was conducted using the Deform-3D ver.5.0 code. The important information concerned with the deformation area characteristic, material flow, and velocity field has been presented. Otherwise, the location of the neutral plane in the deformation area was shown clearly.

关键词： numerical simulation 3-D deformation roll forging

On Room-Temperature Inversion of EPR Signals of P1 Centre in Synthetic Diamond

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Chinese Physics Letters 2009年第1期26卷 317-320页

作者： g. g. Fedoruk O. N. Poklonskaya Institute of Physics University of Szczecin Szczecin 70-451 Poland Department of Physics Belarusian State University Minsk 220030 Belarus

Room-temperature inversion of EPR absorption signals of P1 centre in synthetic diamond is studied by the transient nutation technique. Use of the bichromatic field, consisting of a transverse microwave field and longitudinal radio frequency field, allows to investigate the dynamics of P1 centres in the same field configuration as in cw EPR spectrometers. It is shown that the annealing decreases the P1 centre concentration and, respectively, increases the spin-spin relaxation time. As a result, the periodic inversion （nutation） of the P1 centre absorption signal is observed longer. It is assumed that the P1 centre signal inversion, which was previously observed by cw EPR, might be caused by the Bloch-Siegert effect in the bichromatic field.

关键词： field emission molybdenum dioxide enhancement factor

Thrombospondin-1 expression correlates with angiogenesis in experimental cirrhosis

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World Journal of gastroenterology 2008年第14期14卷 2213-2217页

作者： gülsüm zlem Elpek güzide Ayse gkhan Sevgi Bozova Akdeniz University Medical School Department of Pathology Antalya 07070 Turkey

AIM:To investigate the significance of Thrombospondin-1 (TSP-1) expression and its relationship with angiogenesis during experimental fibrosis. METHODS:Cirrhosis was induced in male Wistar rats by intraperitoneal administration of diethyl nitrosamine (DEN). The serial sections from liver tissues were stained with anti-CD34 and anti-TSP-1 antibodies before being quantitated by light microscopy. RESULTS:Our results showed that of TSP-1 expression gradually increases according to the severity of fibrosis (groupⅠvs group Ⅱ, group Ⅲ and group Ⅳ;group Ⅱ vs group Ⅲ and group Ⅳ;group Ⅲ vs group Ⅳ, P giogenesis (P giogenesis provided by this study suggests that besides its role as a strong promoter of transforming growth factor-β1 (TgF-β1), TSP-1 might have an additional role in liver fibrogenesis by stimulating angiogenesis and this protein could be a potential target to prevent fibrogenesis in chronic inflammatory diseases of the liver.

关键词： Experimental liver cirrhosis Immuno-histochemistry Liver fibrosis Pathologic angiogenesis Thrombospondin-1

Harmonics in the Squirrel Cage Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 86-102页

作者： g.Kovács the ganz Electric Works BudapestHungary

The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. However, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the ***, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques

Harmonics in the Squirrel Cage Induction Motor Analytic Calculation-Part Ⅰ: Differential Leakage, Attenuation, Asynchronous Parasitic Torques

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CES Transactions on Electrical Machines and Systems 2023年第4期7卷 320-329页

作者： g.Kovács ganz Electric Works 1095 BudapestHungary

The magnetic field generated in the air gap of the cage asynchronous machine and the harmonics of the magnetomotive forces creating that magnetic field, as well as the related differential leakage, attenuation, asynchronous parasitic torques have been discussed in great detail in the literature, but always separately, for a long time. However, systematization of the phenomenon still awaits. Therefore, it is worth summarizing the completeness of the phenomena in a single study – with a new approach at the same time-in order to reveal the relationships between them. The role of rotor slot number is emphasized much more than before. An existing, commonly used, but still impractical basic figure has been modified to more clearly demonstrate the response of the rotor for the harmonics of the stator. The need to treat differential leakage, asynchronous parasitic torques and attenuation together will be demonstrated: new formula for asynchronous parasitic torque is derived;the long-used characteristic curves for differential leakage and attenuation used separately so far was merged into one, correct curve in order to provide a correct design guide for the engineers.

关键词： Asynchronous parasitic torque Attenuation Differential leakage Squirrel cage induction motor Winding harmonics

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Proton-neutron symplectic model description of ^(20)Ne

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Chinese Physics C 2022年第4期46卷 141-149页

作者： H.g.ganev Joint Institute for Nuclear Research DubnaRussia

A microscopic description of the low-lying positive-parity rotational bands in ^(20)Ne is given within the framework of the symplectic-based proton-neutron shell-model approach provided by the proton-neutron symplectic model(PNSM).For this purpose,a model Hamiltonian is *** includes an algebraic interaction lying in the enveloping algebra of the Sp(12,R)dynamical group of the PNSM,which introduces both horizontal and vertical mixings of different SU(3)irreducible representations within the Sp(12,R)irreducible collective space of ^(20)Ne.A good overall description is obtained for the excitation energies of the ground and first two excited β bands,including the ground state intraband B(E2)quadrupole collectivity and the known interband B(E2)transition probabilities between the low-lying collective states,without utilizing an effective charge.

关键词： proton-neutron symplectic model shell-model states collective states in^(20)Ne