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D^0~0 mixing and other recent charm results from bAbAR

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Chinese Physics C 2010年第6期34卷 780-787页

作者： b.Meadows University of Cincinnati Department of Physics

Studies in which bAbAR data have shown evidence for mixing in the neutral charm meson system are presented. A new measurement of the lifetime difference parameter ycp = （1.16±0.22±0.18）% is described. Results are also presented from a systematic study of DK and D＊K invariant mass distributions from a 470 fb^-1 sample of asymmetric e^＋e^- interactions recorded by the bAbAR detector at the PEP-Ⅱ storage rings. A new charmed-strange meson has been observed with mass [3044 ± 8stat （-5^＋30 ）syst] MeV/c^2 and width [239± 35stat （-42^＋46）syst]MeV/c^2.

关键词： mixing oscillations charm meson spectroscopy

ＯＮＮＯＮＬＩＮＥＡＲＤＩＦＦＥＲＥＮＴＩＡＬＧＡＬＯＩＳＴＨＥＯＲＹ

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Chinese Annals of Mathematics,Series b 2002年第2期23卷 219-226页

作者： b.MALGRANGE Universite

Let X denote a complex analytic manifold, and let Aut(X) denote the space of invertible maps of a germ (X, a) to a germ (X, b); this space is obviously a groupoid; roughly speaking, a 'Lie groupoid' is a subgroupoid of Aut(X) defined by a system of partial differential *** a foliation with singularities on X one attaches such a groupoid, e.g. the smallest one whose Lie algebra contains the vector fields tangent to the foliation. It is called 'the Galois groupoid of the foliation'. Some examples are considered, for instance foliations of codimension one, and foliations defined by linear differential equations; in this last case one recuperates the usual differential Galois group.

关键词： Differential Galois group Complex analytic manifold Lie groupoid

T-duality as permutation of coordinates in double space

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Chinese Physics C 2017年第5期41卷 16-25页

作者： b.Sazdovic Institute of Physics University of Belgrade 11001 Belgrade P.O.Box 57 Serbia

We introduce the 2D dimensional double space with the coordinates Z^M=（x~μ,y_μ）,whose components are the coordinates of initial space x~μ and its T-dual y_μ.We shall show that in this extended space the T-duality transformations can be realized simply by exchanging the places of some coordinates x^a,along which we want to perform T-duality,and the corresponding dual coordinates y_*** such an approach it is evident that T-duality leads to the physically equivalent theory and that a complete set of T-duality transformations forms a subgroup of the 2D permutation ***,in double space we are able to represent the backgrounds of all T-dual theories in a unified manner.

关键词： duality coordinates subgroup permutation unified inverse arbitrary connect exchanging physically

Spatial distribution of δ2H and δ18O values in the hydrologic cycle of the Nile basin

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Journal of Arid Land 2015年第2期7卷 133-145页

作者： Jeff b LANGMAN School of Science and Engineering American University in Cairo Department of Geological Sciences University of Idaho

Existing δ2H and δ18O values for precipitation and surface water in the Nile basin were used to analyze precipitation inputs and the influence of evaporation on the isotopic signal of the Nile River and its tributaries. The goal of the data analysis was to better understand basin processes that influence seasonal streamflow for the source waters of the Nile River, because climate and hydrologic models have continued to produce high uncertainty in the prediction of precipitation and streamflow in the Nile basin. An evaluation of differences in precipitation δ2H and δ18O values through linear regression and distribution analysis indicate variation by region and season in the isotopic signal of precipitation across the Nile basin. The White Nile basin receives precipitation with a more depleted isotopic signal compared to the blue Nile basin. The hot temperatures of the Sahelian spring produce a greater evaporation signal in the precipitation isotope distribution compared to precipitation in the Sahara/Mediterranean region, which can be influenced by storms moving in from the Mediterranean Sea. The larger evaporative effect is reversed for the two regions in summer because of the cooling of the Sahel from inflow of Indian Ocean monsoon moisture that predominantly influences the climate of the blue Nile basin. The regional precipitation isotopic signals convey to each region＇s streamflow, which is further modified by additional evaporation according to the local climate. Isotope ratios for White Nile streamflow are significantly altered by evaporation in the Sudd, but this isotopic signal is minimized for streamflow in the Nile River during the winter, spring and summer seasons because of the flow dominance of the blue Nile. During fall, the contribution from the White Nile may exceed that of the blue Nile, and the heavier isotopic signal of the White Nile becomes apparent. The variation in climatic conditions of the Nile River basin provides a means of identifying mech

关键词： Nile River arid environment deuterium excess regional climate model uncertainty evaporation isotope effects

bending characteristic of a cantilevered magnetostrictive film-substrate system

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Science China(Technological Sciences) 2007年第4期50卷 454-461页

作者： b. Narsu Institute of Science and Technology Inner Mongolia University

The bending problem of a film-substrate cantilever with arbitrary film-to-substrate thickness ratio is solved exactly by employing the force equilibrium equation, and then the optimization and application of the bending characteristic of the magne-tostrictive cantilever is discussed. Furthermore, the influence of geometrical and physical parameters of the two cantilever components on the maximum free-end deflection of the cantilever is addressed. The results indicate that as the substrate thickness is kept constant, the greater film-to-substrate stiffness ratio will induce a larger deflection, while for the case of fixed total cantilever thickness, the optimal cantilever deflection is independent of the physical parameters of the materials such as Young’s modulus and Poisson’s ratio.

关键词： magnetic film-substrate system cantilever deflection sensors

ON A CLASS OF KTHE SEQUENCE SPACES WITH NORMAL STRUCTURE

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Acta Mathematica Scientia 2011年第2期31卷 576-590页

作者： b. Zlatanov Department of Mathematics and Informatics Plovdiv University

In this note, we investigate the generalized modulus of convexity δ（λ） and the generalized modulus smoothness p（λ）. We obtain some estimates of these moduli for X=lp. We obtain inequalities between WCS coefficient of a KSthe sequence space X and δX（λ）. We show that, for a wide class of class the sequence spaces X, if for some ε∈（0, 9/10] holds δx（e）〉 1/3（1- √3/2）ε, then X has normal structure.

关键词： Weakly convergent sequence coefficient modulus of convexity generalizedmodulus of convexity normal structure

Testosterone and its metabolites： differential associations with cardiovascular and cerebrovascular events in men

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Asian Journal of Andrology 2018年第2期20卷 109-114页

作者： bu b Yeap School of Medicine University of Western Australia Perth Western Australia 6009 Australia Deportment of Endocrinology and Diabetes Fiona Stanley Hospital Perth Western Australia 6150 Australia

As men grow older, circulating testosterone declines while the incidence of cardiovascular disease increases. Thus, the role of sex hormones as biomarkers, and possibly contributing factors to clinical manifestations of cardiovascular disease in the increasing demographic of aging men, has attracted considerable interest. This review focuses on observational studies of endogenous androgens, namely circulating testosterone and dihydrotestosterone, which have examined their associations with cardiovascular events such as myocardial infarction and stroke. Studies which have examined the associations of endogenous estrogens, namely circulating estradiol, with these outcomes are also discussed. In large prospective cohort studies of predominantly middle-aged and older men, lower circulating testosterone consistently predicts higher incidence of cardiovascular events. Of note, both lower circulating testosterone and lower dihydrotestosterone are associated with higher incidence of stroke. These associations are less apparent when myocardial infarction is considered as the outcome. Results for estradiol are inconsistent. Lower circulating testosterone has been shown to predict higher cardiovascular disease-related mortality, as has lower circulating dihydrotestosterone. It is possible that the relationship of circulating androgens to cardiovascular events or mortality outcomes may be U-shaped rather than linear, with an optimal range defining men at lowest risk. Epidemiological studies are observational in nature and do not prove causality. Associations observed in studies of endogenous androgens need not necessarily translate into similar effects of exogenous androgens. Rigorous randomized controlled trials are needed to clarify the effects of testosterone treatment on cardiovascular risk in men.

关键词： cardiovascular disease cardiovascular-related mortality dihydrotestosterone estradiol male aging myocardial infarction stroke testosterone

From geometry to non-geometry via T-duality

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Chinese Physics C 2018年第8期42卷 65-87页

作者： b.Sazdovi Institute of Physics University of Belgrade

Reconsideration of the T-duality of the open string allows us to introduce some geometric features in non-geometric ***,we have found what symmetry is T-dual to the local gauge *** includes transformations of background fields but does not include transformations of the *** to this we have introduced a new,up to now missing term,with additional gauge field Ai^D（D denotes components with Dirichlet boundary conditions）.It compensates non-fulfilment of the invariance under such transformations on the end-points of an open string,and the standard gauge field AaN（N denotes components with Neumann boundary conditions）compensates non-fulfilment of the gauge *** a generalized procedure we will perform T-duality of vector fields linear in *** show that gauge fields AaNand AiDare T-dual to ADaand AN^*** introduce the field strength of T-dual non-geometric theories as derivatives of T-dual gauge fields along both T-dual variable yμand its double？yμ.This definition allows us to obtain gauge transformation of non-geometric theories which leaves the T-dual field strength ***,we introduce some new features of non-geometric theories where field strength has both antisymmetric and symmetric *** allows us to define new kinds of truly non-geometric theories.

关键词： T-duality non-geometry open string neumann boundary conditions dirichlet boundary conditions

Magnetic reversal and magnetic memory effect in melt-spun Pr_2Fe_(14)b/α-Fe nanocomposite ribbons

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Journal of Rare Earths 2015年第12期33卷 1303-1309页

作者：韩广兵苏浩高汝伟于淑云康仕寿朱明刚李卫 X.b.Liu School of Physics Shandong University Division of Functional Materials Central Iron & Steel Research Institute Department of Physics University of Texas at Arlington

The influence of CoCr addition on the microstructure and magnetic properties was investigated in nanocomposite Pr2Fel4b/a-Fe alloys prepared by melt spinning. It was shown that the magnetic properties of Pr2Fel4b/ct-Fe nanocomposite were im- proved by an addition of 10 at.% CoCr, in particular, coercivity （Hc） from 4.9 up to 5.3 kOe, maximum energy product （（bH）max） from 10.6 up to 13.9 MGOe, and remanence （Mr） from 94.2 up to 98.4 emu/g. The field dependencies of the reversible and irreversible magnetization components were derived from the recoil loops. Combining with the initial magnetization curves, the results indi- cated that the pinning of domain walls at the grain boundaries dominated the magnetization reversal in Pr2Fe14b/ct-Fe nanocomposite alloys. The magnetic memory effect was studied by measuring the magnetic moment relaxation at a cycle negative magnetic field with time interval of 600 s. The exchange-spring magnets with magnetic memory effect have a high potential for high density magnetic recording.

关键词： magnetization reversal exchange coupling magnetic memory effect nanocomposite alloys coercivity rare earths