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Current experiments do not support, as ATLAS and CMS collaborations at the Large Hadron Collider reported, that the Higgs-like resonance discovered in July 2012 is a pure CP-odd state. We examine a general $hZZ$ vertex which contains CP-even and CP-odd couplings, by studying the process $h\to ZZ^*\to l_1^+l_1^-l_2^+l_2^-$ with $l_1,\, l_2= e$ or $\mu$, to explore the CP mixed property of the Higgs-like particle. One momentum asymmetry and two angular asymmetries have been analyzed in order to reveal the difference from different CP-couplings. Our study shows that these asymmetries could be interesting observables in the future precise experiments., Comment: 13 pages, 6 figures, references and some discussion added

L. Cappiello1,2, O. Cata3, G. D’Ambrosio2,a, Dao-Neng Gao4 Dipartimento di Scienze Fisiche, Universita di Napoli “Federico II”, Via Cintia, 80126 Naples, Italy INFN-Sezione di Napoli, Via Cintia, 80126 Naples, Italy Fakultat fur Physik, Arnold Sommerfeld Center for Theoretical Physics, Ludwig-Maximilians-Universitat Munchen, 80333 Munich, Germany Interdisciplinary Center for Theoretical Study and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China

Mobile business is one of young promising e-commerce industries. In mobile business scenario, PKI and certifications have been the premier solution to secure mobile transactions. However, client devices with limited computing and storage resources have difficulties to discover and validate the certification path, since this process costs large computing and communication resources. In this paper, we focus on utilizing the distributed and resourceful features of cloud to provide flexible and traceable path validation services for mobile business. This service is compatible with current standard Delegated Certification Validation protocols. All mobile devices can make the validation requests to our “delegation cloud” from world-range locations and get a swift response, regardless how complex the certification path is.

Topic detection is a novel technology which structures news stories into several topics. Present topic detection approaches are mainly based on clustering algorithms such as single pass or agglomerative clus-tering, and all these algorithms need at least one input parameter. We proposed a novel clustering algorithm which auto-matically determines the parameters for each corpus. Experimental results show that the parameters derived are close to optimal, and our algorithm has similar accuracy as the UPGMA algorithm which is manually set with optimal parameters. Another advantage of our algorithm is that it runs much faster than the UPGMA algorithm. Keywords : Topic Detection, Clustering Algorithm, Parameter Free, Similarity Distribution 1. Introduction Nowadays web pages have become the fastest ways for us to achieve news and publish individual opinions. It is hard to identify what pages exactly we want. By giving a set of keywords to search engines such as Google and Yahoo!, we can obtain a very long list of URLs referring to Web pages. However, it is still a difficult work to grasp and summarize the contents quickly from the search results. We need a convenient and efficient way to learn “what’s happened” or “what’s hot” from large number of news web pages. Topic detection is such a method which automatically finds topics in a group of news corpuses. At present, topic detection is widely applied to web information organization, such as automatic construction of online news issues [1] or organization of RSS news from different sources on topics [2]. It is easy to think of the use of data mining algorithms to find topics. Actually, clustering is the core algorithm of present topic detection approaches. Common clustering algorithms used for topic detection include single pass, kNN and agglomerative clustering [1][3][4][5]. A drawback of these algorithms is that they can not run automatically without manual intervention. A common solution for the above problem is to use fixed parameters for all corpuses when they are similar in size and structure. A representative work on this approach is [1] which uses the UPGMA agglomerative clustering algorithm and specifies a fixed threshold to control the termination of the algorithm. But according to our experiments, when size or structure varies among corpuses, the optimal thresholds vary largely. We suppose that different corpuses have different optimal parameters regardless of which algorithm and parameters are used, and it is impossible for users to determine the optimal

A novel digital design of space-vector pulse width modulator (SVPWM) is presented. The proposed design is implemented on a FPGA (XC3S500E) from Xilinx. The whole design structure contains three level pipelines, with adjustable switching frequency and dead time, whose parameters should be adapted to the different situations. So the design is more universal. Experimental results show that this design can present high performance in its switching frequency and accuracy. And very few resources on the chip are used, so more resources are ready for other function modules.

Belle Collaboration reported a new observed value of K*-(892) mass by studying tau --> K_S pi nu_tau decay, which is significantly different from the current world average value given by Particle Data Group 2006. Motivated by this new data, we revisit the issue on the K*0(892)-K*+(892) mass splitting. Our theoretical estimation favors the new measurement by Belle Collaboration. Therefore further experimental efforts are urgently needed to improve our understanding of these issues., 5 pages, minor changes, references added

We study possible scalar type interactions in tau^- -->pi^- pi^0 nu_tau decay. One finds that an angular distribution asymmetry, A(s), can be induced from the interference between the scalar part and vector part amplitudes in this decay. Our analysis shows that, in the two-Higgs-doublet model of type II with large tan beta, the charged Higgs contribution could make A(s) up to 10^{-3} without conflict with present experimental constraints. Thus in the future precise experiments in tau-charm factories, this angular distribution asymmetry may be an interesting observable either to be helpful in searching for the signal of the charged Higgs boson or to impose the significant bound on it.

Motivated by some new experimental and theoretical efforts, we update the theoretical analysis of the electron-positron energy asymmetry, which arises, in K_L --> pi0 e+ e-, from the two-photon intermediate state in the standard model. It is found that the measurement of this asymmetry in future experiments may increase our understanding of the K_{L, S} --> pi0 e+ e- decays, which would thus provide some useful information on quark flavor physics. Meanwhile, in the standard model the electron-positron energy asymmetry in the decay of K_S --> pi0 e+ e- is expected to be vanishingly small, therefore the asymmetry in K_S --> pi0 e+ e- might be a very interesting quantity to explore new physics scenarios., Comment: 11 pages, 4 figures. Two figures added to show the sensitivity of the asymmetry to a_S and a_V, and some discussions added. To appear in Phys. Lett. B

The long-distance contribution via the two-photon intermediate state to the forward-backward asymmetries in decays K+ --> pi+ l+ l- (l=e and mu) has been studied within the standard model. In order to evaluate the dispersive part of the K+ --> pi+ gamma* gamma* --> pi+ l+ l- amplitude, we employ a phenomenological form factor to soften the ultraviolet behavior of the transition. It is found that, this long-distance transition, although subject to some theoretical uncertainties, can lead to significant contributions to the forward-backward asymmetries, which could be tested in the future high-precise experiments., Comment: 13 pages, 5 figures

CD152, a ligand expressed on the surface of the activated T cells that inhibits co-stimulatory signals, is associated with negative regulation of T-cell activation in the antigen-presenting process. In order to interfere with immune signal transmission, obtain functional proteins with specific immunosuppressive effects, and regulate the immune response, we cloned the full-length extracellular domain of CD152 into the expression vector pPICTLA and transformed Pichia pastoris GS115 cells by electroporation. Yeast colonies expressing and secreting large quantities of the extracellular soluble fragment of CD152 (sCD152) were isolated, and the protein was purified and used in assays designed to investigate the ability of sCD152 to regulate the immune system. In a series of antigen specific immune response interference tests in mice, human allogeneic mixed lymphocyte reaction and antigen specific lymphocyte transformation tests, we found that sCD152 had a marked immunosuppressive effect. This protein reduced antibody titer in mice immunized with BSA, significantly inhibited the killing of antibody-dependent cytotoxicity and CTL-mediated donor target cells, and reduced the expression of IL2 in mice. In the absence of exposure of sCD152, long-term stimulation (>5 days) by the same antigen in vivo partially restored the immune response-correlated stimulation index (SI), showing the characteristics of a primary immune response. Following the deletion of sCD152, however, there was no obvious inhibitory effect on the primary immune response triggered by the nonrelevant antigen OVA, indicating that sCD152 had an antigen-specific immunosuppressive effect and that the inhibitory effect of sCD152 required the co-administration of antigen. These findings suggest that sCD152 may have clinical potential as an immunosuppressive agent.

The CP-violating charge asymmetry in decays K+- --> \pi+- \gamma\gamma, which is induced by the electromagnetic penguin operators, has been studied both in thestandard model and in its extensions. Because of a large enhancement of the Wilson coefficients of the electromagnetic penguin operators in the supersymmetric extensions of the standard model, a significant upper bound on this charge asymmetry could be expected, and thus high precision measurements of this interesting CP-violating quantity might explore new physics effects beyond the standard model.

The decay [Formula: see text] is investigated beyond the standard model. Interestingly, the upper limit of the CP-conserving and CP-violating branching ratios of the decay, induced from the possible extensions of the standard model, would be larger than the corresponding branching ratios given in the standard model respectively, and it is expected that the CP-violating part could be enhanced.

Supersymmetric extensions of the Standard Model predict a large enhancement of the Wilson coefficients of the dimension-five electromagnetic penguin operators affecting the direct CP violation in K_L --> pi^0 e^+ e^- and the charge asymmetry in K^\pm --> pi^\pm l^+ l^-. Here we compute the relevant matrix elements in the chiral quark model and compare these with the ones given by lattice calculations, Comment: 12 pages, JHEP style, gluonic corrections to B_T added

We revisit the calculation of the long-distance contribution to the muon-polarization asymmetry LR ,w hich arises, inK + ! ++ , from the two-photon intermediate state. The parity-violating amplitude of this process, induced by the local anomalous K + transition, is analysed; unfortunately, one cannot expect to predict its contribution to the asymmetry by using chiral perturbation theory alone. Here we evaluate this amplitude and its contribution to LR by employing a phenomenological model called the FMV model, in which the utility of the vector and axial-vector resonances exchange is important to soften the ultraviolet behaviour of the transition. We nd that the long-distance contribution is of the same order of magnitude as the standard model short-distance contribution.

Motivated by diquark exchange, we construct a class of extensions of the standard model. These models can generate large CP conserving and CP violating contributions to the doubly Cabbibo suppressed decays D^0\to K^+\pi^- without affecting D^0-\overline{D^0} mixing, contrary to what is usually believed in the literature. We find an interesting specific realization of these models, which has the LR chiral structure and can induce novel density \times density operators. It is new for non-leptonic kaon decays, and particularly, may provide a possible solution to the \Delta I=1/2 rule and direct CP violation, without inducing large flavour changing neutral currents., Comment: LaTeX, 12 pages and 2 eps figures. Minor changes, paper accepted by Physics Letters B

In the framework of $\mathrm{U}(3{)}_{L}\ifmmode\times\else\texttimes\fi{}\mathrm{U}(3{)}_{R}$ chiral theory of mesons, $\ensuremath{\pi}K$ elastic scattering is studied. The s-wave and p-wave scattering lengths ${(a}_{0}^{3/2}, {a}_{0}^{1/2}, {a}_{1}^{3/2},$ and ${a}_{1}^{1/2})$ and phase shifts $({\ensuremath{\delta}}_{0}^{3/2}, {\ensuremath{\delta}}_{0}^{1/2}, {\ensuremath{\delta}}_{1}^{3/2},$ and ${\ensuremath{\delta}}_{1}^{1/2}),$ the total elastic scattering cross section ${\ensuremath{\sigma}}_{\mathrm{tot}}({\ensuremath{\pi}}^{+}{K}^{+})$ and ${\ensuremath{\sigma}}_{\mathrm{tot}}({\ensuremath{\pi}}^{\ensuremath{-}}{K}^{+}),$ and the p-wave cross section ${\ensuremath{\sigma}}_{p}({\ensuremath{\pi}}^{\ensuremath{-}}{K}^{+})$ are calculated. Theoretical results are in agreement with the experimental data. There is no new parameter in this study.

We study a new contribution, which is a tree-level transition from long-distance dynamics, to K+→π+ℓ+ℓ- (ℓ = e, μ) decays. It is found that this tree-diagram can be calculated unambiguously and would generate the additional contribution to the vector, axial-vector, scalar and pseudoscalar form factor of the decay. Our analysis shows that these form factors are strongly suppressed and this long-distance contribution is well under control.

We discuss how the combined analysis of $B\to K\nu\bar\nu$ and $B\to Kl^+l^-$ can provide us with new physics tests practically free of form factor uncertainties. Residual theory errors are at the level of several percent. This study underlines the excellent motivation for measuring these modes at a Super Flavour Factory, or, in the case of $B\to Kl^+l^-$, also at a hadron collider.

A phenomenological analysis of K???? (KL??+??? and K+??+?0?) with the direct emission photon is carried out beyond the leading order in the chiral perturbation theory. We show that the experimental evidence for the large photon energy dependence of the magnetic amplitude in KL??+??? seems to indicate an interesting consequence: vector meson dominance must be implemented at O(p4), which is not a general feature of the chiral perturbation theory. The phenomenology of K+??+?0? is also analyzed using the same scheme.