Weak radiative decays of the B mesons belong to the most important flavor changing processes that provide constraints on physics at the TeV scale. In the derivation of such constraints, accurate standard model predictions for the inclusive branching ratios play a crucial role. In the current Letter we present an update of these predictions, incorporating all our results for the O(α_{s}^{2}) and lower-order perturbative corrections that have been calculated after 2006. New estimates of nonperturbative effects are taken into account, too. For the CP- and isospin-averaged branching ratios, we find B_{sγ}=(3.36±0.23)×10^{-4} and B_{dγ}=(1.73_{-0.22}^{+0.12})×10^{-5}, for E_{γ}>1.6 GeV. Both results remain in agreement with the current experimental averages. Normalizing their sum to the inclusive semileptonic branching ratio, we obtain R_{γ}≡(B_{sγ}+B_{dγ})/B_{cℓν}=(3.31±0.22)×10^{-3}. A new bound from B_{sγ} on the charged Higgs boson mass in the two-Higgs-doublet-model II reads M_{H^{±}}>480 GeV at 95% C.L.

Raman, Raman optical activity (ROA), infrared (IR), and vibrational circular dichroism (VCD) spectra of cysteine in aqueous solution have been measured and calculated by means of density functional theory. The influence of aqueous environment on the spectra of cysteine has been simulated by means of implicit (polarizable continuum model) and explicit (molecular dynamics, solute-solvent clusters) methods. The results indicate that, while PCM reproduces some of the features of the spectra, the best description is rendered by the microsolvation model (solute-solvent clusters). The shape of the bands is in some cases more correctly reproduced by MD, but their intensities and positions are not, since these simulations are hampered by the standard force field being parametrized for conformations of peptides rather than isolated amino acids. The calculated ROA spectra have been used to extract conformational ratios from the experimental spectra, and again, the best results (as verified by simulations of other spectra) have been obtained when using the microsolvation model. This procedure renders three zwitterion conformers dominating the spectra of hydrated cysteine, of conformational ratios of 35, 33, and 24%, respectively.

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Autoimmune diseases are characterized by the loss of immune tolerance to self-antigens which leads to an excessive immune responses and chronic inflammation. Although much progress has been made in revealing key players in pathophysiology of various autoimmune diseases, their therapy remains challenging and consists of conventional immunosuppressive treatments, including corticosteroids and more advanced biological therapies which are targeted at molecules involved in maintaining chronic inflammation. These therapies are focused on suppressing inflammation; nevertheless, a permanent balance between protective and pathogenic immune responses is not achieved. In addition, most of currently available therapies for autoimmune diseases induce severe side effects. Consequently, more effective and safer therapies are still required to control autoimmunity. Stress-induced cell protecting heat shock proteins (HSP) have been considered as a potential treatment targets for autoimmune diseases. HSP, predominantly intracellular components, might be released from bacteria or mammalian tissues and activate immune response. This activation may lead to either production of (auto)antibodies against HSP and/or induction of immune regulatory mechanisms, including expansion of desired T regulatory (Treg) cells. Because inadequate frequency or activity of Treg is a characteristic feature of autoimmune diseases, targeting this cell population is an important focus of immunotherapy approaches in autoimmunity.

Weak radiative decay "B ! X s is known to be a loop-generated process. However, it does receive tree-level contributions from Cabibbo-Kobayashi-Maskawa-suppressed b ! u " us transitions. In the present paper, we evaluate such contributions together with similar ones from the QCD penguin operators. For a low value of the photon energy cutoff E 0 ' m b =20 that has often been used in the literature, they can enhance the inclusive branching ratio by more than 10%. For E 0 ¼ 1:6 GeV or higher, the effect does not exceed 0.4%, which is due to phase-space suppression. Our perturbative results contain collinear logarithms that depend on the light quark masses m q (q ¼ u, d, s). We have allowed m b =m q to vary from 10 to 50, which corresponds to values of m q that are typical for the constituent quark masses. Such a rough method of estimation may be improved in the future with the help of fragmentation functions once the considered effects begin to matter in the overall error budget for Bð " B ! X s Þ.

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