1,220 research outputs found

    New Production Mechanism of Neutral Higgs Bosons with Right scalar tau neutrino as the LSP

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    Motived by the neutrino oscillation data, we consider the lightest tau sneutrino Îœ~τ1\tilde \nu_{\tau_1} (which is mostly the right tau sneutrino) to be the lightest supersymmetric particle (LSP) in the framework of the minimal supersymmetric Standard Model. Both the standard and the non-standard trilinear scalar coupling terms are included for the right tau sneutrino interactions. The decay branching ratio of Îœ~τ2→Μ~τ1+h0\tilde \nu_{\tau_2} \to \tilde \nu_{\tau_1}+ h^0 can become so large that the production rate of the lightest neutral Higgs boson (h0h^0) can be largely enhanced at electron or hadron colliders, either from the direct production of Îœ~τ2\tilde \nu_{\tau_2} or from the decay of charginos, neutralinos, sleptons, and the cascade decay of squarks and gluinos, etc. Furthermore, because of the small LSP annihilation rate, Îœ~τ1\tilde \nu_{\tau_1} can be a good candidate for cold dark matter.Comment: 11 pages, RevTex, 3 eps figures. We clarify the theoretical framework of this study, with a note added in the end, and correct an equation, with updated figure

    Novas neuroterapĂȘuticas em psiquiatria: racional e uso da estimulação transcraniana por corrente contĂ­nua no transtorno depressivo maior

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    Background : Transcranial direct current stimulation (tDCS) is a novel non-pharmacological intervention being investigated for the treatment of major depressive disorder (MDD). Objective : To perform an updated review of tDCS for MDD. Method : Systematic review in Medline/PubMed and other databases of all clinical studies evaluating the clinical efficacy of tDCS in MDD, from the first date available to December/2013. Results : Out of 55 articles, 24 were included, being 6 open-label studies; 8 randomized, double-blind, sham-controlled trials; 2 follow-up studies; 2 meta-analyses and 6 case reports. We observed an improvement of 20-40% in depressive symptoms, being slightly better in open studies. Five randomized clinical trials displayed positive results. The meta-analyses presented mixed results; although none included the study of Brunoni et al. (2013) that represents almost 50% of the evaluated sample. Open-label studies and case reports also investigated tDCS in bipolar depression, post-stroke depression and employed different parameters of stimulation. Discussion : TDCS is a novel, promising treatment for MDD. Definite evidence from large, ongoing clinical trials will be available in the next years.Contexto : A estimulação transcraniana por corrente contĂ­nua (ETCC) Ă© uma nova intervenção nĂŁo farmacolĂłgica investigada como tratamento no transtorno depressivo maior (TDM). Objetivo : Apresentar uma revisĂŁo atualizada da ETCC no TDM. MĂ©todo : RevisĂŁo sistemĂĄtica no banco de dados Medline/PubMed e outros de todos os estudos clĂ­nicos publicados avaliando a eficĂĄcia da ETCC no TDM, da primeira data disponĂ­vel a dezembro/2013. Resultados : De 55 artigos, 24 foram incluĂ­dos, sendo 6 estudos abertos; 8 ensaios clĂ­nicos randomizados, duplo-cego, placebo controlados; 2 estudos de seguimento; 2 metanĂĄlises e 6 relatos de caso. Observa-se uma melhora de 20-40% nos sintomas depressivos, sendo ligeiramente maior nos estudos abertos. Entre os ensaios controlados, 5 demonstraram eficĂĄcia da tĂ©cnica. As metanĂĄlises divergiram quanto aos resultados, mostrando presença e ausĂȘncia de eficĂĄcia e ausĂȘncia da ETCC. PorĂ©m, nenhuma incluiu o estudo de Brunoni et al. (2013), que representa quase 50% da população estudada. Estudos abertos e relatos de caso tambĂ©m investigaram o uso da ETCC na depressĂŁo bipolar, na depressĂŁo pĂłs-AVC e usaram variaçÔes nos parĂąmetros de estimulação. ConclusĂ”es : A ETCC Ă© uma tĂ©cnica promissora no tratamento da TDM. EvidĂȘncias definitivas devem estar disponĂ­veis nos prĂłximos anos, com a divulgação de resultados de grandes ensaios clĂ­nicos em andamento

    Tight--binding description of the quasiparticle dispersion of graphite and few--layer graphene

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    A universal set of third--nearest neighbour tight--binding (TB) parameters is presented for calculation of the quasiparticle (QP) dispersion of NN stacked sp2sp^2 graphene layers (N=1...∞N=1... \infty) with ABAB stacking sequence. The QP bands are strongly renormalized by electron--electron interactions which results in a 20% increase of the nearest neighbour in--plane and out--of--plane TB parameters when compared to band structure from density functional theory. With the new set of TB parameters we determine the Fermi surface and evaluate exciton energies, charge carrier plasmon frequencies and the conductivities which are relevant for recent angle--resolved photoemission, optical, electron energy loss and transport measurements. A comparision of these quantitities to experiments yields an excellent agreement. Furthermore we discuss the transition from few layer graphene to graphite and a semimetal to metal transition in a TB framework.Comment: Corresponding author: A. Gr\"uneis Tel.: +49 351 4659 519 e--mail: [email protected]

    On the complementarity of Hyper-K and LBNF

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    The next generation of long-baseline experiments is being designed to make a substantial step in the precision of measurements of neutrino-oscillation probabilities. Two qualitatively different proposals, Hyper-K and LBNF, are being considered for approval. This document outlines the complimentarity between Hyper-K and LBNF.Comment: 5 pager

    Initial report from the ICFA Neutrino Panel

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    In July 2013 ICFA established the Neutrino Panel with the mandate "To promote international cooperation in the development of the accelerator-based neutrino-oscillation program and to promote international collaboration in the development a neutrino factory as a future intense source of neutrinos for particle physics experiments". This, the Panel's Initial Report, presents the conclusions drawn by the Panel from three regional "Town Meetings" that took place between November 2013 and February 2014. After a brief introduction and a short summary of the status of the knowledge of the oscillation parameters, the report summarises the approved programme and identifies opportunities for the development of the field. In its conclusions, the Panel recognises that to maximise the discovery potential of the accelerator-based neutrino-oscillation programme it will be essential to exploit the infrastructures that exist at CERN, FNAL and J-PARC and the expertise and resources that reside in laboratories and institutes around the world. Therefore, in its second year, the Panel will consult with the accelerator-based neutrino-oscillation community and its stakeholders to: develop a road-map for the future accelerator-based neutrino-oscillation programme that exploits the ambitions articulated at CERN, FNAL and J-PARC and includes the programme of measurement and test-beam exposure necessary to ensure the programme is able to realise its potential; develop a proposal for a coordinated "Neutrino RD" programme, the accelerator and detector R&D programme required to underpin the next generation of experiments; and to explore the opportunities for the international collaboration necessary to realise the Neutrino Factory.Comment: ICFA Neutrino Panel 2014(01

    Erythropoietin Modulates the Structure of Bone Morphogenetic Protein 2–Engineered Cranial Bone

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    The ideally engineered bone should have similar structural and functional properties to the native tissue. Although structural integrity is critical for functional bone regeneration, we know less about modulating the structural properties of the engineered bone elicited by bone morphogenetic protein (BMP) than efficacy and safety. Erythropoietin (Epo), a primary erythropoietic hormone, has been used to augment blood transfusion in orthopedic surgery. However, the effects of Epo on bone regeneration are not well known. Here, we determined the role of Epo in BMP2-induced bone regeneration using a cranial defect model. Epo administration improved the quality of BMP2-induced bone and more closely resembled natural cranial bone with a higher bone volume (BV) fraction and lower marrow fraction when compared with BMP2 treatment alone. Epo increased red blood cells (RBCs) in peripheral blood and also increased hematopoietic and mesenchymal stem cell (MSC) populations in bone marrow. Consistent with our previous work, Epo increased osteoclastogenesis both in vitro and in vivo. Results from a metatarsal organ culture assay suggested that Epo-promoted osteoclastogenesis contributed to angiogenesis because angiogenesis was blunted when osteoclastogenesis was blocked by alendronate (ALN) or osteoprotegerin (OPG). Earlier calcification of BMP2-induced temporary chondroid tissue was observed in the Epo+BMP group compared to BMP2 alone. We conclude that Epo significantly enhanced the outcomes of BMP2-induced cranial bone regeneration in part through its actions on osteoclastogenesis and angiogenesis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98479/1/ten%2Etea%2E2011%2E0742.pd
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