Yukawa couplings and proton decay in SUSY models

We discuss proton decay induced by dimension--5 operators in supersymmetric models containing extra hypercharge-1/3 color-triplets. We derive a general formula relating dimension-5 operator to the color-triplet mass matrix. We show that certain zeros in the triplet mass-matrix together with some triplet coupling selection rules can lead to elimination of dimension-5 operators. We apply this mechanism to SU(5) and flipped SU(5) theories with extended Higgs sectors.Comment: 6 pages, uses JHEP.cls, talk given at the Trieste Meeting of the TMR Network on Physics Beyond the Standard Model, 24-27 February 1999, Trieste, Italy (to appear in the proceedings

Lepton-Flavor Violation with Non-universal Soft Terms

We study the lepton-flavor violation processes tau ->mu gamma and mu->e gamma in two different examples of models with non-universal soft breaking terms derived from strings. We show that the predictions are quite different from those of universal scenarios. Non-universal A-terms provide an interesting framework to enhance the supersymmetric contributions to CP violation effects. We observe that in the case of the lepton-flavor violation we study, the non-universality of the scalar masses enhances the branching ratios more significantly than the non-universality of the A-terms. We find that the current experimental bounds on these processes restrict both the parameter space of the models and the texture of the Yukawa couplings which predicts the lepton masses, providing at the same time an interesting experimental test for physics beyond the Standard Model.Comment: 15 pages, 6 figures minor change

An Improved Analysis of b→sγb\to s\gamma in Supersymmetry

An improved analysis of the $b\to s+\gamma$ decay in the minimal flavor violating case is given taking into account additional contributions in the supersymmetric sector which enter in the next-to-leading-order (NLO) and are enhanced by $\tan\beta$ factors. Specifically, we compute a set of twenty one-loop diagrams to give the most complete analysis to date of the NLO supersymmetric corrections. These modifications are computed from the effective charged Higgs and neutral Higgs couplings involving twelve loop diagrams for the charged Higgs sector and eight loop diagrams for the neutral Higgs sector. While the computations of these corrections are available in the literature, their full forms including the complex phase dependence has not be considered. Our analysis takes account of the full allowed set of twenty one-loop diagrams and is more general since it also includes the full dependence on CP phases in non universal sugra and MSSM models. A numerical analysis is carried out to estimate the size of the corrections to $b\to s+\gamma$. We also briefly discuss the implications of these results for the search for supersymmetry.Comment: 46 pages, 11 figure

Biochemical Basis of Topoisomerase I Relaxation Activity Reduction by Nonenzymatic Lysine Acetylation

The relaxation activity of topoisomerase I is required for regulation of global and local DNA supercoiling. The in vivo topoisomerase I enzyme activity is sensitive to lysine acetylation⁻deacetylation and can affect DNA supercoiling and growth as a result. Nonenzymatic lysine acetylation by acetyl phosphate has been shown to reduce the relaxation activity of topoisomerase I. In this work, the biochemical consequence of topoisomerase I modification by acetyl phosphate with enzymatic assays was studied. Results showed that noncovalent binding to DNA and DNA cleavage by the enzyme were reduced as a result of the acetylation, with greater effect on DNA cleavage. Four lysine acetylation sites were identified using bottom-up proteomics: Lys13, Lys45, Lys346, and Lys488. The Lys13 residue modified by acetyl phosphate has not been reported previously as a lysine acetylation site for topoisomerase I. We discuss the potential biochemical consequence of lysine acetylation at this strictly conserved lysine and other lysine residues on the enzyme based on available genetic and structural information

Dark Matter Searches with Cherenkov Telescopes: Nearby Dwarf Galaxies or Local Galaxy Clusters?

In this paper, we compare dwarf galaxies and galaxy clusters in order to elucidate which object class is the best target for gamma-ray DM searches with imaging atmospheric Cherenkov telescopes (IACTs). We have built a mixed dwarfs+clusters sample containing some of the most promising nearby dwarf galaxies (Draco, Ursa Minor, Wilman 1 and Segue 1) and local galaxy clusters (Perseus, Coma, Ophiuchus, Virgo, Fornax, NGC 5813 and NGC 5846), and then compute their DM annihilation flux profiles by making use of the latest modeling of their DM density profiles. We also include in our calculations the effect of DM substructure. Willman 1 appears as the best candidate in the sample. However, its mass modeling is still rather uncertain, so probably other candidates with less uncertainties and quite similar fluxes, namely Ursa Minor and Segue 1, might be better options. As for galaxy clusters, Virgo represents the one with the highest flux. However, its large spatial extension can be a serious handicap for IACT observations and posterior data analysis. Yet, other local galaxy cluster candidates with more moderate emission regions, such as Perseus, may represent good alternatives. After comparing dwarfs and clusters, we found that the former exhibit annihilation flux profiles that, at the center, are roughly one order of magnitude higher than those of clusters, although galaxy clusters can yield similar, or even higher, integrated fluxes for the whole object once substructure is taken into account. Even when any of these objects are strictly point-like according to the properties of their annihilation signals, we conclude that dwarf galaxies are best suited for observational strategies based on the search of point-like sources, while galaxy clusters represent best targets for analyses that can deal with rather extended emissions. Finally, we study the detection prospects for present and future IACTs in the framework of the constrained minimal supersymmetric standard model. We find that the level of the annihilation flux from these targets is below the sensitivities of current IACTs and the future CTA

Программный комплекс оперативного обслуживания жилого комплекса

The aim of this research is to develop two methods to help us understand the fundamental distinctionsamong human activities in terms of spatial occupancy. To characterize the features of the distribution ofhuman activities in a space (and over time), we introduce the concept of “activity shapes.” To obtain adistinctive analysis of activity shapes, we ran an experiment in which a group of six adults shared a fully covisiblespace and sequentially performed three specific activities characterized as eccentric, concentric, ordistributed. We video recorded the three scenarios using overhead cameras that allowed us to closely mapparticipants’ positions on the floor layout, obtaining the data in two formats: 1) a sequence of images fromthe overhead videos, automatically stored and pre‐computed to extract and aggregate motion; and 2) adataset of individuals’ identification and positions over time, manually annotated after repeatedobservations of the videos. Using the images sequence, we qualitatively analyzed the activity shapes usingViz‐A‐Vis, a tool for visualizing of activity through computer vision (Romero et al., 2008; 2011). Using thedataset, we performed two analyses: 1) the geometry and the topology of the activity shapes; and 2) theirspatiotemporal configurations, introducing the use of statistical analysis of space occupancy patterns. Whileit is not possible to generalize to all activity conditions from these three samples, we discovered sometendencies in the activity shapes. Our findings revealed several main distinctions in terms of geometry,topology, dispersion, gravitation, and clustering; supporting the development of the methods presented inthis work and directions of future implementation of these analyses in more complex spaces and scenariosthat complement space syntax analysis.QC 20160407</p