2,920 research outputs found

    Covariant derivative of the curvature tensor of pseudo-K\"ahlerian manifolds

    Full text link
    It is well known that the curvature tensor of a pseudo-Riemannian manifold can be decomposed with respect to the pseudo-orthogonal group into the sum of the Weyl conformal curvature tensor, the traceless part of the Ricci tensor and of the scalar curvature. A similar decomposition with respect to the pseudo-unitary group exists on a pseudo-K\"ahlerian manifold; instead of the Weyl tensor one obtains the Bochner tensor. In the present paper, the known decomposition with respect to the pseudo-orthogonal group of the covariant derivative of the curvature tensor of a pseudo-Riemannian manifold is refined. A decomposition with respect to the pseudo-unitary group of the covariant derivative of the curvature tensor for pseudo-K\"ahlerian manifolds is obtained. This defines natural classes of spaces generalizing locally symmetric spaces and Einstein spaces. It is shown that the values of the covariant derivative of the curvature tensor for a non-locally symmetric pseudo-Riemannian manifold with an irreducible connected holonomy group different from the pseudo-orthogonal and pseudo-unitary groups belong to an irreducible module of the holonomy group.Comment: the final version accepted to Annals of Global Analysis and Geometr

    Association of CSF sTREM2, a marker of microglia activation, with cholinergic basal forebrain volume in major depressive disorder

    Get PDF
    BACKGROUND: Inflammatory mechanisms are believed to contribute to the manifestation of major depressive disorder (MDD). Central cholinergic activity may moderate this effect. Here, we tested if volume of the cholinergic basal forebrain is associated with cerebrospinal fluid (CSF) levels of sTREM2 as a marker of microglial activation in people with late life MDD. METHODS: Basal forebrain volume was determined from structural MRI scans and levels of CSF sTREM2 with immunoassay in 29 people with late-life MDD and 20 healthy older controls at baseline and 3 years follow-up. Associations were determined using Bayesian analysis of covariance. RESULTS: We found moderate level of evidence for an association of lower CSF levels of sTREM2 at 3 years follow up with MDD (Bayes factor in favor of an effect = 7.9). This level of evidence prevailed when controlling for overall antidepressant treatment and CSF levels of markers of AD pathology, i.e., Aβ42/Aβ40, ptau181 and total tau. Evidence was in favor of absence of an effect for baseline levels of CSF sTREM2 in MDD cases and for baseline and follow up data in controls. LIMITATIONS: The sample size of repeated CSF examinations was relatively small. Therefore, we used Bayesian sequential analysis to assess if effects were affected by sample size. Still, the number of cases was too small to stratify effects for different antidepressive treatments. CONCLUSIONS: Our data agree with the assumption that central cholinergic system integrity may contribute to regulation of microglia activity in late-life MDD

    Preseason Training Improves Perception of Fatigue and Recovery From a Futsal Training Session.

    Full text link
    Purpose: To compare the posttraining recovery timeline of elite Brazilian futsal athletes before (Pre-PS) and after 10 weeks of the preseason (Post-PS) period of high-intensity technical–tactical training. Methods: At the start (n = 13) and at the end of the preseason (n = 7), under-20 male futsal players undertook fitness testing for maximal aerobic power, the countermovement jump (CMJ), and the 10-m sprint with change of direction. Furthermore, at both Pre-PS and Post-PS, the players participated in a training session where performance and psychophysiological measures were recorded before, immediately, 3, 24, and 48 hours postsession. The measures included CMJ, 10-m sprint, creatine kinase, Total Quality Recovery Scale, and Brunel Mood Scale. Effect size (ES) analyses compared fitness and posttraining recovery values for each parameter at Pre-PS versus Post-PS. Results: Only trivial ES (−0.02 to 0.11) was evident in maximal aerobic power, CMJ, and 10-m sprint at Post-PS compared with Pre-PS. For the timeline of recovery, only trivial and small ESs were evident for the 10-m sprint (−0.12 to 0.49), though CMJ recovery was improved at 3 hours (0.87) and 48 hours (1.27) at Post-PS and creatine kinase was lower at 48 hours (−1.33) at Post-PS. Perception of recovery was improved in Post-PS at 3 hours (1.50) and 24 hours postsession (0.92). Furthermore, perception of effort was lower immediately after the session (−0.29), fatigue was lower at 3 hours (−0.63), and vigor responses were improved in all postseason assessments (0.59 to 1.13). Conclusion: Despite minimal changes in fitness, preseason training attenuated players' perception of effort and fatigue and improved their recovery profile following a high-intensity technical–tactical training session

    Protective Effect of Nasal Colonisation with ∆cps/piaA and ∆cps/proABCStreptococcus pneumoniae Strains against Recolonisation and Invasive Infection

    Get PDF
    RATIONALE: Nasopharyngeal administration of live virulence-attenuated Streptococcus pneumoniae strains is a potential novel preventative strategy. One target for creating reduced virulence S. pneumoniae strains is the capsule, but loss of the capsule reduces the duration of S. pneumoniae colonisation in mice which could impair protective efficacy against subsequent infection. OBJECTIVES: To assess protective efficacy of nasopharyngeal administration of unencapsulated S. pneumoniae strains in murine infection models. METHODS: Strains containing cps locus deletions combined with the S. pneumoniae virulence factors psaA (reduces colonisation) or proABC (no effect on colonisation) were constructed and their virulence phenotypes and ability to prevent recolonisation or invasive infection assessed using mouse infection models. Serological responses to colonisation were compared between strains using ELISAs, immunoblots and 254 S. pneumoniae protein antigen array. Measurements and Main Results: The ∆cps/piaA and ∆cps/proABC strains were strongly attenuated in virulence in both invasive infection models and had a reduced ability to colonise the nasopharynx. ELISAs, immunoblots and protein arrays showed colonisation with either strain stimulated weaker serological responses than the wild type strain. Mice previously colonised with these strains were protected against septicaemic pneumonia but, unlike mice colonised with the wild type strain, not against S. pneumoniae recolonisation. CONCLUSIONS: Colonisation with the ∆cps/piaA and ∆cps/proABC strains prevented subsequent septicaemia, but in contrast, to published data for encapsulated double mutant strains they did not prevent recolonisation with S. pneumoniae. These data suggest targeting the cps locus is a less effective option for creating live attenuated strains that prevent S. pneumoniae infections

    Anais do XXII Seminário de Formação de Professores para o MERCOSUL/ CONE SUL

    Get PDF
    1036 p. : tabs.Homenagem ao professor Augusto Nibaldo Silva TriviñosEvento realizado em Porto Alegre de 3 a 7 de novembro de 2014Apresentação: O XXII Seminário de Formação de Professores para o MERCOSUL/ CONE SUL, está concebido dentro da problemática geral do projeto intitulado “A formação de professores para o MERCOSUL/CONE SUL (Argentina, Bolívia, Brasil, Chile, Paraguai, Uruguai e Venezuela): princípios, objetivos e modalidades. Perspectivas de uma formação básica, comum, geral”, fundado em agosto de 1993, com sede na Universidade Federal do Rio Grande do Sul – UFRGS, no qual participam professores pesquisadores dos sete países mencionados. Os vinte e dois anos de existência refletidos em vida intelectual e em bases de amizade, de fraternidade, de respeito, de cooperação, de sentimentos coletivos, além do interesse individual, de Grupo, de Nação, antecipam a possibilidade de intercambiar idéias no XXII Seminário Internacional de Investigação sobre a Formação de Professores para o MERCOSUL/CONE SUL, com a temática central: Formação do Professor como Pesquisador da/para América Latina: Augusto Nibaldo Silva Triviños, a ser realizado na Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, de 03 a 07 de novembro de 2014. A realização do Seminário, organizado pelo Grupo brasileiro, permitirá projetar os possíveis próximos passos do Grupo, debater as pesquisas efetuadas, integrar os projetos sobre a Formação do Professor como Pesquisador, apresentar proposições, especialmente, para os sistemas educacionais do MERCOSUL/CONE SUL, além de divulgar e organizar, pelo menos, uma publicação em forma de livro. Os Seminários anteriores foram realizados anualmente e de modo alternado entre os países integrantes do grupo: Brasil (1993, 1994, 2002, 2006, 2009 e 2010), Chile (1995, 1998, 2003, 2005 e 2012), Argentina (1996, 2000, 2004, 2008 e 2013), Uruguai (1997, 2001 e 2011), Paraguai (1999) e Venezuela (2007). Tal Evento, para sua realização, depende do apoio das universidades nas quais os pesquisadores estão vinculados, das instituições participantes e dos organismos de fomento à pesquisa para consolidar a formação de professores e pesquisadores já realizada pelas instituições envolvidas, com possibilidade de divulgação para a sociedade brasileira, latino-americana e em particular do MERCOSUL/CONE SUL

    Optimizing the colour and fabric of targets for the control of the tsetse fly Glossina fuscipes fuscipes

    Get PDF
    Background: Most cases of human African trypanosomiasis (HAT) start with a bite from one of the subspecies of Glossina fuscipes. Tsetse use a range of olfactory and visual stimuli to locate their hosts and this response can be exploited to lure tsetse to insecticide-treated targets thereby reducing transmission. To provide a rational basis for cost-effective designs of target, we undertook studies to identify the optimal target colour. Methodology/Principal Findings: On the Chamaunga islands of Lake Victoria , Kenya, studies were made of the numbers of G. fuscipes fuscipes attracted to targets consisting of a panel (25 cm square) of various coloured fabrics flanked by a panel (also 25 cm square) of fine black netting. Both panels were covered with an electrocuting grid to catch tsetse as they contacted the target. The reflectances of the 37 different-coloured cloth panels utilised in the study were measured spectrophotometrically. Catch was positively correlated with percentage reflectance at the blue (460 nm) wavelength and negatively correlated with reflectance at UV (360 nm) and green (520 nm) wavelengths. The best target was subjectively blue, with percentage reflectances of 3%, 29%, and 20% at 360 nm, 460 nm and 520 nm respectively. The worst target was also, subjectively, blue, but with high reflectances at UV (35% reflectance at 360 nm) wavelengths as well as blue (36% reflectance at 460 nm); the best low UV-reflecting blue caught 3× more tsetse than the high UV-reflecting blue. Conclusions/Significance: Insecticide-treated targets to control G. f. fuscipes should be blue with low reflectance in both the UV and green bands of the spectrum. Targets that are subjectively blue will perform poorly if they also reflect UV strongly. The selection of fabrics for targets should be guided by spectral analysis of the cloth across both the spectrum visible to humans and the UV region

    An unusual case of an isolated capitellar fracture of the right elbow in a child: a case report

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>Although elbow fractures have a high incidence in the pediatric population, fractures of the capitellum are almost exclusively observed in individuals older than 12 years of age. Due to their rarity in children, reports with large numbers of cases are lacking in the literature and the surgical treatment options are poorly defined.</p> <p>Case presentation</p> <p>We present the case of an 11-year-old Portuguese girl with a displaced fracture of the capitellum of the right elbow, a typical Hahn-Steinthal or Type 1 fracture, which was followed for one year. The treatment and outcome of this fracture are described. Our patient underwent an open reduction and internal fixation with two cannulated screws. There were no complications and normal elbow function was recovered.</p> <p>Conclusion</p> <p>The authors believe that cannulated screw fixation is a reliable method of treatment for Type 1 capitellar fracture in children because it enables good interfragmentary compression, early mobilization, faster functional elbow recovery and implant removal is rarely necessary.</p

    MicroRNA Fingerprints Identify miR-150 as a Plasma Prognostic Marker in Patients with Sepsis

    Get PDF
    BACKGROUND: The physiopathology of sepsis continues to be poorly understood, and despite recent advances in its management, sepsis is still a life-threatening condition with a poor outcome. If new diagnostic markers related to sepsis pathogenesis will be identified, new specific therapies might be developed and mortality reduced. Small regulatory non-coding RNAs, microRNAs (miRNAs), were recently linked to various diseases; the aim of our prospective study was to identify miRNAs that can differentiate patients with early-stage sepsis from healthy controls and to determine if miRNA levels correlate with the severity assessed by the Sequential Organ Failure Assessment (SOFA) score. METHODOLOGY/PRINCIPAL FINDINGS: By using genome-wide miRNA profiling by microarray in peripheral blood leukocytes, we found that miR-150, miR-182, miR-342-5p, and miR-486 expression profiles differentiated sepsis patients from healthy controls. We also proved by quantitative reverse transcription-polymerase chain reaction that miR-150 levels were significantly reduced in plasma samples of sepsis patients and correlated with the level of disease severity measured by the SOFA score, but were independent of the white blood counts (WBC). We found that plasma levels of tumor necrosis factor alpha, interleukin-10, and interleukin-18, all genes with sequence complementarity to miR-150, were negatively correlated with the plasma levels of this miRNA. Furthermore, we identified that the plasma levels ratio for miR-150/interleukin-18 can be used for assessing the severity of the sepsis. CONCLUSIONS/SIGNIFICANCE: We propose that miR-150 levels in both leukocytes and plasma correlate with the aggressiveness of sepsis and can be used as a marker of early sepsis. Furthermore, we envision miR-150 restoration as a future therapeutic option in sepsis patients

    First evidence for Wollemi Pine-type pollen (Dilwynites: Araucariaceae) in South America

    Get PDF
    We report the first fossil pollen from South America of the lineage that includes the recently discovered, extremely rare Australian Wollemi Pine, Wollemia nobilis (Araucariaceae). The grains are from the late Paleocene to early middle Eocene Ligorio Márquez Formation of Santa Cruz, Patagonia, Argentina, and are assigned to Dilwynites, the fossil pollen type that closely resembles the pollen of modern Wollemia and some species of its Australasian sister genus, Agathis. Dilwynites was formerly known only from Australia, New Zealand, and East Antarctica. The Patagonian Dilwynites occurs with several taxa of Podocarpaceae and a diverse range of cryptogams and angiosperms, but not Nothofagus. The fossils greatly extend the known geographic range of Dilwynites and provide important new evidence for the Antarctic region as an early Paleogene portal for biotic interchange between Australasia and South America.Mike Macphail, Raymond J. Carpenter, Ari Iglesias, Peter Wil
    corecore