730 research outputs found

    The quadratic spinor Lagrangian is equivalent to the teleparallel theory

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    The quadratic spinor Lagrangian is shown to be equivalent to the teleparallel / tetrad representation of Einstein's theory. An important consequence is that the energy-momentum density obtained from this quadratic spinor Lagrangian is essentially the same as the ``tensor'' proposed by Moller in 1961.Comment: 10 pages, RevTe

    Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

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    A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

    On the verge of Umdeutung in Minnesota: Van Vleck and the correspondence principle (Part One)

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    In October 1924, the Physical Review, a relatively minor journal at the time, published a remarkable two-part paper by John H. Van Vleck, working in virtual isolation at the University of Minnesota. Van Vleck combined advanced techniques of classical mechanics with Bohr's correspondence principle and Einstein's quantum theory of radiation to find quantum analogues of classical expressions for the emission, absorption, and dispersion of radiation. For modern readers Van Vleck's paper is much easier to follow than the famous paper by Kramers and Heisenberg on dispersion theory, which covers similar terrain and is widely credited to have led directly to Heisenberg's "Umdeutung" paper. This makes Van Vleck's paper extremely valuable for the reconstruction of the genesis of matrix mechanics. It also makes it tempting to ask why Van Vleck did not take the next step and develop matrix mechanics himself.Comment: 82 page

    Unveiling the kinomes of leishmania infantum and L. braziliensis empowers the discovery of new kinase targets and antileishmanial compounds

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    Leishmaniasis is a neglected tropical disease caused by parasites of the genus Leishmania (NTD) endemic in 98 countries. Although some drugs are available, current treatments deal with issues such as toxicity, low efficacy, and emergence of resistance. Therefore, there is an urgent need to identify new targets for the development of new antileishmanial drugs. Protein kinases (PKs), which play an essential role in many biological processes, have become potential drug targets for many parasitic diseases. A refined bioinformatics pipeline was applied in order to define and compare the kinomes of L. infantum and L. braziliensis, species that cause cutaneous and visceral manifestations of leishmaniasis in the Americas, the latter being potentially fatal if untreated. Respectively, 224 and 221 PKs were identified in L. infantum and L. braziliensis overall. Almost all unclassified eukaryotic PKs were assigned to six of nine major kinase groups and, consequently, most have been classified into family and subfamily. Furthermore, revealing the kinomes for both Leishmania species allowed for the prioritization of potential drug targets that could be explored for discovering new drugs against leishmaniasis. Finally, we used a drug repurposing approach and prioritized seven approved drugs and investigational compounds to be experimentally tested against Leishmania. Trametinib and NMS-1286937 inhibited the growth of L. infantum and L. braziliensis promastigotes and amastigotes and therefore might be good candidates for the drug repurposing pipeline17352361FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE GOIÁS - FAPE

    Quiropterofauna Do Cerrado Leste Maranhense, Brasil, Com Ocorrência De Novos Registros. Biota Neotropica

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    In Brazil, 179 bat species have been recorded to date, representing 68 genera and nine families. Few data are available on the bat fauna of the state of Maranhão, so the present study was based on a survey of the bat fauna of the Inhamum Municipal Environmental Protection Area (APA Inhamum) in the Cerrado savanna of the eastern extreme of the state. This inventory provides new records of bat species for the state of Maranhão and the Cerrado biome. A total of 31 species (four families) were collected, representing 39% of the bat species known to occur in Maranhão and 28.71% of the species described for the Cerrado. The family Phyllostomidae was the most diverse, with 23 species (74.20% of the total), and also the most abundant, with 86.09% of the specimens collected. The Molossidae (four species) was the second most diverse, followed by the Vespertilionidae (three species) and the Emballonuridae (one species). Carollia perspicillata was the most abundant species (28%).The records of Artibeus fimbriatus and Platyrrhinus fusciventris are the first for the Cerrado and were also recorded in Maranhão for the first time. The cumulative species curve did not reach an asymptote. The species Dermanura gnoma, Lasiurus blossevillii, Lasiurus ega, Micronycteris schmidtorum, Molossops temminckii, Platyrrhinus cf. recifinus, Phylloderma stenops and Trachops cirrhosus, were also recorded in Maranhão for the first time demonstrating the value of for mammal inventories and emphasizing the need for further surveys in this poorly-known region. © 2016, Universidade Estadual de Campinas UNICAMP. All Rights Reserved.16

    The preparation of HEMA-MPC films for ocular drug delivery

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    There is a need to prolong drug residence time using a biocompatible formulation in the subconjunctival space after surgery to treat glaucoma. Drug releasing discs were prepared with 2-(hydroxyethyl)methacrylate (HEMA) and 2-methacryloyl-oxyethyl phosphorylcholine (MPC). The ratio of bound water (Wb) to free water (Wf) ratio increased from 1:0.3 to 1:6.8 with increasing MPC (0 to 50%, w/w). The optimal balance between water content, SR and mechanical strength were obtained with 10% MPC (w/w) hydrogels. Water-alcohol mixtures were examined to facilitate loading of poorly soluble drugs, and they showed greater hydrogel swelling than either water or alcohol alone. The SR was 1.2 ± 0.02 and 3.3 ± 0.1 for water and water:ethanol (1:1) respectively. HEMA-MPC (10%) discs were loaded with dexamethasone using either water:ethanol (1:1) or methanol alone. Drug release was examined in an outflow rig model that mimics the subconjunctival space in the eye. Dexamethasone loading increased from 0.3 to 1.9 mg/disc when the solvent was changed from water:ethanol (1:1) to methanol with the dexamethasone half-life (t½) increasing from 1.9 to 9.7 days respectively. These encouraging results indicate that HEMA-MPC hydrogels have the potential to sustain the residence time of a drug in the subconjunctival space of the eye

    Toxoplasma gondii effectors are master regulators of the inflammatory response

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    Toxoplasma is a highly successful parasite that establishes a life-long chronic infection. To do this, it must carefully regulate immune activation and host cell effector mechanisms. Here we review the latest developments in our understanding of how Toxoplasma counteracts the immune response of the host, and in some cases provokes it, through the use of specific parasite effector proteins. An emerging theme from these discoveries is that Toxoplasma effectors are master regulators of the pro-inflammatory response, which elicits many of the toxoplasmacidal mechanisms of the host. We speculate that combinations of these effectors present in certain Toxoplasma strains work to maintain an optimal parasite burden in different hosts to ensure parasite transmission.Knights Templar Eye Foundation, Inc.American Heart Association (0835099N)Massachusetts Life Sciences Center (New Investigator Award)Singapore-MIT Alliance for Research and Technology (SMART)National Institutes of Health (U.S.) (NIH RO1-AI080621)New England Regional Center of Excellence for Biodefense and Emerging Infectious Diseases (NERCE Developmental Grant)National Cancer Institute (U.S.) (Irvington Postdoctoral Fellowship Program

    Aspectos da cienciometria aplicados a um estudo de caso: área de Letras

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    This article originated from a master's dissertation, submitted to the Graduate Program in Sciences of Information at the Pontifícia Universidade Católica de Campinas. Such dissertation conducted an analysis of citations of bibliographical references/bibliography found in theses and dissertations submitted during the years 1999 to 2002, in the following areas of Letters: Linguistics, Literary Theory, and Comparative Literature. Those theses had been conducted in departments of three state universities in São Paulo state: Faculdade de Filosofia, Ciências e Letras at Universidade de São Paulo, in the state capital; Faculdade de Ciências e Letras at Universidade Estadual Paulista Júlio de Mesquita Filho, in the city of Assis; and Instituto de Estudos da Linguagem at Universidade Estadual de Campinas, in the county of Campinas. The occurrences of document citations were verified in electronic support, by means of the scientometric method. Aspects related to the characteristics of the documents were registered, such as: books, articles in periodicals, scientific events, theses and dissertations. Citations of documents retrieved by means of electronic media, and citations of printed documents were compared quantitatively. A sample of 229 theses and dissertations was selected, out of a total of 539 works concluded in the above mentioned universities. By means of semi-structured interviews, quality indicators were obtained regarding the dissemination policies for printed and electronic documents in the Humanities, particularly in the area of Letters. The period covered by the research had its starting year defined by the implementation of Program of Electronic Library, by the São Paulo State Foundation for Research Support, which provided the state's public universities with the access to electronic journals.O presente artigo originou-se do conteúdo desenvolvido na dissertação de mestrado, apresentada ao Programa de Pós-Graduação em Ciência da Informação da Pontifícia Universidade Católica de Campinas, na qual procedeu-se a uma análise das citações de referências bibliográficas/bibliografia consultadas, das teses e dissertações nas subáreas de Lingüística e Teoria Literária e Literatura Comparada, produzidas no período de 1999 a 2002, nas faculdades de Letras das seguintes universidades estaduais paulistas: Universidade de São Paulo - Faculdade de Filosofia, Letras e Ciências Humanas; Universidade Estadual de São Paulo Júlio de Mesquita Filho - Faculdade de Ciências e Letras de Assis e Universidade Estadual de Campinas - Instituto de Estudos da Linguagem. Verificou-se a incidência das citações de documentos em suporte eletrônico, a partir do método cienciométrico. Foram detectados aspectos referentes às características dos documentos citados, tais como livros, artigos de periódicos, eventos científicos, teses e dissertações. Compararam-se quantitativamente as citações de documentos em suporte eletrônico e as citações de documentos impressos, a partir de uma amostra estratificada de 229 teses e dissertações, de um total de 534 trabalhos defendidos nas referidas universidades. Através de entrevistas semi-estruturadas, foram obtidos indicadores de qualidade para as políticas de divulgação de documentos impressos e eletrônicos para as Ciências Humanas, especificamente para a área de Letras. O período examinado na pesquisa foi definido a partir do ano da implantação do Programa de Biblioteca Eletrônica, pela Fundação para Amparo da Pesquisa do Estado de São Paulo, que possibilitou o acesso a periódicos eletrônicos para as universidades públicas paulistas.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Ciências e Letras de Assis Seção de Referência, Atendimento ao Usuário e DocumentaçãoUniversidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Ciências e Letras de Assis Departamento de Psicologia Experimental e do TrabalhoUniversidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Ciências e Letras de Assis Seção de Referência, Atendimento ao Usuário e DocumentaçãoUniversidade Estadual Paulista Júlio de Mesquita Filho Faculdade de Ciências e Letras de Assis Departamento de Psicologia Experimental e do Trabalh

    Measurement of the correlation between flow harmonics of different order in lead-lead collisions at √sNN = 2.76 TeV with the ATLAS detector

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    Correlations between the elliptic or triangular flow coefficients vm (m=2 or 3) and other flow harmonics vn (n=2 to 5) are measured using √sNN=2.76 TeV Pb+Pb collision data collected in 2010 by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 7 μb−1. The vm−vn correlations are measured in midrapidity as a function of centrality, and, for events within the same centrality interval, as a function of event ellipticity or triangularity defined in a forward rapidity region. For events within the same centrality interval, v3 is found to be anticorrelated with v2 and this anticorrelation is consistent with similar anticorrelations between the corresponding eccentricities, ε2 and ε3. However, it is observed that v4 increases strongly with v2, and v5 increases strongly with both v2 and v3. The trend and strength of the vm−vn correlations for n=4 and 5 are found to disagree with εm−εn correlations predicted by initial-geometry models. Instead, these correlations are found to be consistent with the combined effects of a linear contribution to vn and a nonlinear term that is a function of v22 or of v2v3, as predicted by hydrodynamic models. A simple two-component fit is used to separate these two contributions. The extracted linear and nonlinear contributions to v4 and v5 are found to be consistent with previously measured event-plane correlations

    Search for W′→tb→qqbb decays in pp collisions at √s=8 TeV with the ATLAS detector

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    A search for a massive W′ gauge boson decaying to a top quark and a bottom quark is performed with the ATLAS detector in pp collisions at the LHC. The dataset was taken at a centre-of-mass energy of √s=8 TeV and corresponds to 20.3 fb−1 of integrated luminosity. This analysis is done in the hadronic decay mode of the top quark, where novel jet substructure techniques are used to identify jets from high-momentum top quarks. This allows for a search for high-mass W′ bosons in the range 1.5–3.0 TeV. b-tagging is used to identify jets originating from b-quarks. The data are consistent with Standard Model background-only expectations, and upper limits at 95 % confidence level are set on the W′→tb cross section times branching ratio ranging from 0.16pb to 0.33pb for left-handed W′ bosons, and ranging from 0.10pb to 0.21pb for W′ bosons with purely right-handed couplings. Upper limits at 95 % confidence level are set on the W′-boson coupling to tb as a function of the W′ mass using an effective field theory approach, which is independent of details of particular models predicting a W′boson
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