PAMELA Positron Excess as a Signal from the Hidden Sector

The recent positron excess observed in the PAMELA satellite experiment strengthens previous experimental findings. We give here an analysis of this excess in the framework of the Stueckelberg extension of the standard model which includes an extra $U(1)_X$ gauge field and matter in the hidden sector. Such matter can produce the right amount of dark matter consistent with the WMAP constraints. Assuming the hidden sector matter to be Dirac fermions it is shown that their annihilation can produce the positron excess with the right positron energy dependence seen in the HEAT, AMS and the PAMELA experiments. Further test of the proposed model can come at the Large Hadron Collider. The predictions of the $\bar p/p$ flux ratio also fit the data.Comment: 9 pages,3 figures; Breit-Wigner enhancement emphasized; published in PR

Novel genome polymorphisms in BCG vaccine strains and impact on efficacy

Bacille Calmette-Guérin (BCG) is an attenuated strain of Mycobacterium bovis currently used as a vaccine against tuberculosis. Global distribution and propagation of BCG has contributed to the in vitro evolution of the vaccine strain and is thought to partially account for the different outcomes of BCG vaccine trials. Previous efforts by several molecular techniques effectively identified large sequence polymorphisms among BCG daughter strains, but lacked the resolution to identify smaller changes. In this study, we have used a NimbleGen tiling array for whole genome comparison of 13 BCG strains. Using this approach, in tandem with DNA resequencing, we have identified six novel large sequence polymorphisms including four deletions and two duplications in specific BCG strains. Moreover, we have uncovered various polymorphisms in the phoP-phoR locus. Importantly, these polymorphisms affect genes encoding established virulence factors including cell wall complex lipids, ESX secretion systems, and the PhoP-PhoR two-component system. Our study demonstrates that major virulence factors are different among BCG strains, which provide molecular mechanisms for important vaccine phenotypes including adverse effect profile, tuberculin reactivity and protective efficacy. These findings have important implications for the development of a new generation of vaccines

Transcriptional Responses of Leptospira interrogans to Host Innate Immunity: Significant Changes in Metabolism, Oxygen Tolerance, and Outer Membrane

Leptospirosis is an important tropical disease around the world, particularly in humid tropical and subtropical countries. As a major pathogen of this disease, Leptospira interrogans can be shed from the urine of reservoir hosts, survive in soil and water, and infect humans through broken skin or mucous membranes. Recently, host adaptability and immune evasion of L. interrogans to host innate immunity was partially elucidated in infection or animal models. A better understanding of the molecular mechanisms of L. interrogans in response to host innate immunity is required to learn the nature of early leptospirosis. This study focused on the transcriptome of L. interrogans during host immune cells interaction. Significant changes in energy metabolism, oxygen tolerance and outer membrane protein profile were identified as potential immune evasion strategies by pathogenic Leptospira during the early stage of infection. The major outer membrane proteins (OMPs) of L. interrogans may be regulated by the major OmpR specific transcription factor (LB333). These results provide a foundation for further studying the pathogenesis of leptospirosis, as well as identifying gene regulatory networks in Leptospira spp

Blood-Based Gene Expression Profiles Models for Classification of Subsyndromal Symptomatic Depression and Major Depressive Disorder

Subsyndromal symptomatic depression (SSD) is a subtype of subthreshold depressive and also lead to significant psychosocial functional impairment as same as major depressive disorder (MDD). Several studies have suggested that SSD is a transitory phenomena in the depression spectrum and is thus considered a subtype of depression. However, the pathophysioloy of depression remain largely obscure and studies on SSD are limited. The present study compared the expression profile and made the classification with the leukocytes by using whole-genome cRNA microarrays among drug-free first-episode subjects with SSD, MDD, and matched controls (8 subjects in each group). Support vector machines (SVMs) were utilized for training and testing on candidate signature expression profiles from signature selection step. Firstly, we identified 63 differentially expressed SSD signatures in contrast to control (P< = 5.0E-4) and 30 differentially expressed MDD signatures in contrast to control, respectively. Then, 123 gene signatures were identified with significantly differential expression level between SSD and MDD. Secondly, in order to conduct priority selection for biomarkers for SSD and MDD together, we selected top gene signatures from each group of pair-wise comparison results, and merged the signatures together to generate better profiles used for clearly classify SSD and MDD sets in the same time. In details, we tried different combination of signatures from the three pair-wise compartmental results and finally determined 48 gene expression signatures with 100% accuracy. Our finding suggested that SSD and MDD did not exhibit the same expressed genome signature with peripheral blood leukocyte, and blood cell–derived RNA of these 48 gene models may have significant value for performing diagnostic functions and classifying SSD, MDD, and healthy controls

Convergence Of Multidimensional Cascade Algorithm

. A necessary and sufficient condition on the spectrum of the restricted transition operator is given for the convergence in L 2 (R d ) of the multidimensional cascade algorithm for any starting function OE 0 whose shifts form a partition of unity. 1. Introduction This paper is a continuation of [8]. In [8] we obtained a complete characterization of stability and orthonormality of the shifts of a refinable function in terms of its refinenent mask. In this paper we present a complete characterization of the convergence in L 2 (R d ) of the multidimensional cascade algorithm with an arbitrary dilation matrix M in terms of the mask. For fixed integers d 1 and m 2; let M be a d \Theta d dilation matrix with j det(M)j = m: A dilation matrix is an integer matrix with all eigenvalues of modulus ? 1: Let ` 2 (Z d ); where Z d is the set of all multi-integers, be the space of all square-summable sequences, and L 2 (R d ) the space of all square-integrable functions. The..

Effect of concrete modification on shear of connections for timber-concrete composites

2019 ICE Publishing: All rights reserved. Timber-concrete composites (TCCs) take advantage of the properties of timber and concrete simultaneously. TCC slabs consist of timber beams or a timber deck, which resist tensile and bending stresses, connected through different types of shear connectors to an upper concrete slab, which withstands compressive stresses. The stiffness and strength of the slab are mostly defined by the properties of the connectors. To avoid the use of external materials that could be environmentally harmful, micro-notch connections were tested. These micro-notch connections are notches cut into timber elements and filled with wet concrete. The research focused on the influence of the gap between the micro-notches, the experimental configuration, the concrete composition and the concrete curing process on the shear strength of the connectors. The concrete compositions included ground granulated blast-furnace slag (GGBS) and superabsorbent polymer (SAP). These additives were used to evaluate their compliance with the shear strength of the TCC connections. GGBS was used to reduce the cement content in the concrete mix and SAP was used as a water-entraining agent to reduce the autogenous shrinkage of the concrete