277 research outputs found

    Fast and slow-twitching muscles are differentially affected by reduced cholinergic transmission in mice deficient for VAChT: A mouse model for congenital myasthenia

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    Congenital myasthenic syndromes (CMS) result from reduced cholinergic transmission at neuromuscular junctions (NMJs). While the etiology of CMS varies, the disease is characterized by muscle weakness. To date, it remains unknown if CMS causes long-term and irreversible changes to skeletal muscles. In this study, we examined skeletal muscles in a mouse line with reduced expression of Vesicular Acetylcholine Transporter (VAChT, mouse line herein called VAChT-KDHOM). We examined this mouse line for several reasons. First, VAChT plays a central function in loading acetylcholine (ACh) into synaptic vesicles and releasing it at NMJs, in addition to other cholinergic nerve endings. Second, loss of function mutations in VAChT causes myasthenia in humans. Importantly, VAChT-KDHOM present with reduced ACh and muscle weakness, resembling CMS. We evaluated the morphology, fiber type (myosin heavy chain isoforms), and expression of muscle-related genes in the extensor digitorum longus (EDL) and soleus muscles. This analysis revealed that while muscle fibers atrophy in the EDL, they hypertrophy in the soleus muscle of VAChT-KDHOM mice. Along with these cellular changes, skeletal muscles exhibit altered levels of markers for myogenesis (Pax-7, Myogenin, and MyoD), oxidative metabolism (PGC1-alpha and MTND1), and protein degradation (Atrogin1 and MuRF1) in VAChT-KDHOM mice. Importantly, we demonstrate that deleterious changes in skeletal muscles and motor deficits can be partially reversed following the administration of the cholinesterase inhibitor, pyridostigmine in VAChT-KDHOM mice. These findings reveal that fast and slow type muscles differentially respond to cholinergic deficits. Additionally, this study shows that the adverse effects of cholinergic transmission, as in the case of CMS, on fast and slow type skeletal muscles are reversible

    Contribution From Optical Course For The Educational Guidance Of Engineering Careers Students

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    The work shows the fundamental elements of an inclusive educational guidance conception of substantive university processes and results achieved at the Instituto Superior Politécnico José Antonio Echeverría of Havana in the contribution from optical course to develop it for the students in first and second year of the engineering programs, by means of lectures on holography and three-dimensional images of motivation and link with different specialties and the development of experimental facilities and methodology for the construction of holograms and anaglyph by students for engineering applications.9289 IEEE - The Photonics Society,International Commission for Optics (ICO),The Optical Society,The Society of Photo-Optical Instrumentation Engineers (SPIE)Collazo, B., Puentes, M., La orientacin en la actividad pedaggica ¿el maestro, un orientador? (1992) Editorial Pueblo y Educacin, , La HabanaCollazo, B., (2006) Modelo de Tutora Integral Para la Continuidad de Estudios Universitarios en Las Sedes Municipals, , Tesis de doctorado CubaRodrguez, S., (1997) Orientacin Universitaria y Evaluacin de la Calidad. Calidad de la Universidad: Orientacin y Evaluacin, , Apodaca P. y C. Lobato Eds, Barcelona, LaertesEcheverra, B., (1997) Los servicios de orientacin universitarios. Calidad en la universidad: Orientacin y evaluacin, pp. 112-136. , Apodaca P. y C. Lobato (Eds, Barcelona: LaertesMonge, M.C., (2009) Tutora y Orientacin Educative, , Nuevas competencies Las Rozas Wolters KluwerSantana, L.E., (2009) Orientacin Educativa e Intervencin Psicopedaggica Cambian Los Tiempos Cambian Las Responsabilidades Profesionales, , Pirmide MadridVieira, M.J., Vidal, J., Tendencias de la Educacin Superior Europea e implicaciones para la orientacin universitaria (2006) Revista Espaola de Orientacin y Psicopedagoga, 17 (1), pp. 75-97Jaime, R.A., La orientacin educativa como tarea inseparable de la Extensin Universitaria (2011) Revista Cuadernos de Educacin y Desarrollo, 3 (28)Daz, T., La Extensin: Un proceso formativo de la Universidad. Su relacin con otros procesos (2001) Conferencia Magistral Del VI Taller Internacional de Extensin Universitaria, , Memorias, CubaGonzlez, G., (2002) Extensin Universitaria: Una Visin un Cambio Necesario, , Conferencia de la III Convencin Internacional de Educacin Superior, Memorias, CubaOliveira, N., The notorial dynamic analisis of an artificial satellite: A pedagogical experiment in space education (2008) Revista Brasileira de Ensino de Fsica, 30 (1), p. 1401Serra, R., Alfonso, I., Herrera, R., Ferreira, D., Muramatsu, M., Soga, D., (2013) La Fsica y El Trabajo Cientfico Estudiantil en la formación Del Ingeniero Biomdico, , enviado a LAJFE en proceso de arbitraje, eneroSerra, R., (2004) La Utilizacin Del Holograma Como Medio de Enseñanza y de Educacin Social en Cuba A Travs Del Vnculo Investigación-Docencia-Extensin Universitaria, , Tesis Doctoral CubaSerra, R., Moreno, A., Magalhes, D., Muramatsu, M., Lemus, J., Haciendo hologramas en la escuela y en la casa (2010) Revista Brasileira de Ensino de Fsica, 32 (3), p. 3502Zottola, D., Hernndez, A., Serra, R., Anaglifos en la Enseñanza de la ingeniera biomdica (2011) Proc. of v Latin American Congress on Biomedical Engineering, , Haban

    Disk winds of B[e] supergiants

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    The class of B[e] supergiants is characterized by a two-component stellar wind consisting of a normal hot star wind in the polar zone and a slow and dense disk-like wind in the equatorial region. The properties of the disk wind are discussed using satellite UV spectra of stars seen edge-on, i.e. through the equatorial disk. These observations show that the disk winds are extremely slow, 50-90 km/s, i.e. a factor of about 10 slower than expected from the spectral types. Optical emission lines provide a further means to study the disk wind. This is discussed for line profiles of forbidden lines formed in the disk.Comment: 7 pages, LaTeX, 3 ps figures, uses lamuphys.sty from Springer-Verlag, to be published in the proceedings of IAU Coll. 169 "Variable and Non-spherical Stellar Winds in Luminous Hot Stars" held in Heidelberg 199

    Cell atlas of the Atlantic salmon spleen reveals immune cell heterogeneity and cellspecific responses to bacterial infection

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    The spleen is a conserved secondary lymphoid organ that emerged in parallel to adaptive immunity in early jawed vertebrates. Recent studies have applied single cell transcriptomics to reveal the cellular composition of spleen in several species, cataloguing diverse immune cell types and subpopulations.In this study, 51,119 spleen nuclei transcriptomes were comprehensively investigated in the commercially important teleost Atlantic salmon (Salmo salar L.), contrasting control animals with those challenged with the bacterial pathogen Aeromonas salmonicida. We identified clusters of nuclei representing the expected major cell types, namely T cells, B cells, natural killer-like cells, granulocytes, mononuclear phagocytes, endothelial cells, mesenchymal cells, erythrocytes and thrombocytes. We discovered heterogeneity within several immune lineages, providing evidence for resident macrophages and melanomacrophages, infiltrating monocytes, several candidate dendritic cell subpopulations, and B cells at distinct stages of differentiation, including plasma cells and an igt+ subset. We provide evidence for twelve candidate T cell subsets, including cd4+ T helper and regulatory T cells, one cd8+ subset, three γδT subsets, and populations double negative for cd4 and cd8. The number of genes showing differential expression during the early stages of Aeromonas infection was highly variable across immune cell types, with the largest changes observed in macrophages and infiltrating monocytes, followed by resting mature B cells. Our analysis provides evidence for a local inflammatory response to infection alongside B cell maturation in the spleen, and upregulation of ccr9 genes in igt+ B cells, T helper and cd8+ cells, and monocytes, consistent with the recruitment of immune cell populations to the gut to deal with Aeromonas infection. Overall, this study provides a new cell-resolved perspective of the immune actions of Atlantic salmon spleen, highlighting extensive heterogeneity hidden to bulk transcriptomics. We further provide a large catalogue of cell-specific marker genes that can be leveraged to further explore the function and structural organization of the salmonid immune system

    Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

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    This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

    Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

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    The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

    Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

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    We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters

    Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data

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    A measurement of the differential cross-section for the inclusive production of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s) = 7 TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV. The results are based on an integrated luminosity of 35 pb-1, collected with the ATLAS detector at the LHC. The yields of the signal photons are measured using a data-driven technique, based on the observed distribution of the hadronic energy in a narrow cone around the photon candidate and the photon selection criteria. The results are compared with next-to-leading order perturbative QCD calculations and found to be in good agreement over four orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final version published in Physics Letters

    Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

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    This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table, matches published version in Physical Review
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