Revisiting B_s\to\mu^+\mu^- and B\to K^{(*)}\mu^+\mu^- decays in the MSSM with and without R-parity

The rare decays B_s -> \mu^+\mu^- and B -> K^{(*)}\mu^+\mu^- are sensitive to new particles and couplings via their interferences with the standard model contributions. Recently, the upper bound on B(B_s -> \mu^+\mu^-) has been improved significantly by the CMS, LHCb, CDF, and D{\O} experiments. Combining with the measurements of B(B-> K^{(*)}\mu^+\mu^-), we derive constraints on the relevant parameters of minimal supersymmetic standard model with and without R-parity, and examine their contributions to the dimuon forward-backward asymmetry in B-> K^{*}\mu^+\mu^- decay. We find that (i) the contribution of R-parity violating coupling products \lambda^{\prime}_{2i2}\lambda^{\prime*}_{2i3} due to squark exchange is comparable with the theoretical uncertainties in B-> K \mu^+\mu^- decay, but still could be significant in B-> K^{*}\mu^+\mu^- decay and could account for the forward-backward asymmetry in all dimuon invariant mass regions; (ii) the constrained mass insertion (\delta^{u}_{LL})_{23} could have significant contribution to dA_{FB}(B-> K^{*}\mu^+\mu^-)/ds, and such effects are favored by thr recent results of the Belle, CDF, and LHCb experiments.Comment: 20 pages, 9 figures, published versio

(E)-(2,4-Dichloro­benzyl­idene)amino cyclo­propane­carboxyl­ate

In the title compound C11H9Cl2NO2, the dihedral angle between the benzene and cyclo­propane ring planes is 89.95 (13)°. The carbon­yl–oxime grouping is almost coplanar with the benzene ring [dihedral angle = 4.08 (6)°]. In the crystal, mol­ecules are linked by C—H⋯O inter­actions into [100] chains

Higher-order Moment Portfolio Optimization via The Difference-of-Convex Programming and Sums-of-Squares

We are interested in developing a Difference-of-Convex (DC) programming approach based on Difference-of-Convex-Sums-of-Squares (DC-SOS) decomposition techniques for high-order moment (Mean-Variance-Skewness-Kurtosis) portfolio optimization model. This problem can be formulated as a nonconvex quartic multivariate polynomial optimization, then a DC programming formulation based on the recently developed DC-SOS decomposition is investigated. We can use a well-known DC algorithm, namely DCA, for its numerical solution. Moreover, an acceleration technique for DCA, namely Boosted-DCA (BDCA), based on an inexact line search (Armijo-type line search) to accelerate the convergence of DCA for smooth and nonsmooth DC program with convex constraints is proposed. This technique is applied to DCA based on DC-SOS decomposition, and DCA based on universal DC decomposition. Numerical simulations of DCA and Boosted-DCA on synthetic and real datasets are reported. Comparisons with some non-dc programming based optimization solvers (KNITRO, FILTERSD, IPOPT and MATLAB fmincon) demonstrate that our Boosted-DC algorithms can achieve same numerical results with good performance comparable to these efficient methods on solving the high-order moment portfolio optimization model.Comment: 42 pages, 13 figure

Using Peer-to-Peer Technology for Knowledge Sharing in Communities of Practices

Communities of Practices (CoPs) are informal structures within organizations that bind people together through informal relationships and the sharing of expertise and experience. As such, they are effective tools for the creation and sharing of organizational knowledge, and, increasingly, organizations are adopting them as part of their knowledge management strategies. In this paper, we examine the knowledge sharing characteristics and roles of CoPs and develop a peer-to-peer knowledge sharing architecture that matches the behavioral characteristics of the members of the CoPs. We also propose a peer-to-peer knowledge sharing tool called KTella that enables members of CoPs to voluntarily share and retrieve knowledge more effectively

Structure and tanning properties of dialdehyde carboxymethyl cellulose: Effect of degree of substitution

Content: Developing novel tanning agents from renewable biomass is regarded as an effective strategy for sustainable leather industry. In this study, a series of dialdehyde carboxymethyl cellulose (DCMC) were prepared by periodate oxidation of carboxymethyl cellulose (CMC) with varying degrees of substitution (DS: 0.7, 0.9 and 1.2). The structural properties of DCMC were characterized. Size Exclusive Chromatography measurements showed that CMC underwent severe degradation during periodate oxidation, resulting in the decline of weight-average molecular weight from 250,000 g/mol to around 13,000 g/mol. FT-IR analysis illustrated that aldehyde group was successfully introduced into DCMC. The aldehyde group content of DCMC decreased from 8.38 mmol/g to 2.95 mmol/g as the DS rose from 0.7 to 1.2. Interestingly, formaldehyde was found to be produced in DCMC, and its content was 159.4, 151.7 and 38.4 mg/L, respectively when the DS of CMC was 0.7, 0.9 and 1.2, respectively. Further analysis by HPLC found that fructose was formed during oxidative degradation, and was subsequently oxidized to generate formaldehyde. This was in accordance with the fact that higher DS resulted in lower formaldehyde content in DCMC. The whole reaction mechanism is still under investigation at the moment. Tanning trials showed that the shrinkage temperature and thickening rate of DCMC tanned leather decreased as the DS increased. This should be due to the difference in aldehyde content of DCMC. Leather tanned by DCMC-0.7 (DS of CMC was 0.7) had the highest shrinkage temperature of 81°C and thickening rate of 76%. It was noteworthy that the formaldehyde content in DCMC tanned leather was only 0.11-0.40 mg/kg even though DCMC contained a small amount of formaldehyde. In general, we hope the work on dialdehyde tanning agent derived from CMC could provide some essential data for the development of sustainable tanning material and process. Take-Away: 1. Higher degree of substitution (DS) of CMC resulted in lower aldehyde group content of DCMC. 2. The formaldehyde content of DCMC was negatively correlated with DS. 3. The tanning performance of DCMC with lower DS was better