211 research outputs found

    INFLUƊNCIA DE MƉTODOS DE COLETA DE DADOS ESPECTRORRADIOMƉTRICOS SOB ƍNDICES DE VEGETAƇƃO EM EUCALIPTO

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    Objetivou-se verificar a influĆŖncia de mĆ©todos de coleta de folhas em Ć­ndices de vegetaĆ§Ć£o: posiĆ§Ć£o de coleta na copa, orientaĆ§Ć£o cardeal e estaĆ§Ć£o do ano em Eucalyptus grandis. Os dados foram coletados em dois povoamentos distintos em duas Ć”rvores dominantes cada. Foram coletadas 15 folhas em cada posiĆ§Ć£o e em cada orientaĆ§Ć£o, acrescidas de uma amostra de mesmo tamanho no centro. A coleta foi realizada em um Ćŗnico dia, das 13:00 as 15:00 horas. O material foi analisado com o espectrorradiĆ“metro FieldSpecĀ®3 e a resposta espectral de cada orientaĆ§Ć£o e posiĆ§Ć£o foi dada pela mĆ©dia da leitura espectral das folhas. Foram analisados 60 diferentes Ć­ndices de vegetaĆ§Ć£o de acordo com a literatura. Para avaliar o efeito da estaĆ§Ć£o sobre os Ć­ndices foram realizadas coletas nas quatro estaƧƵes do ano, configurando 4 tratamentos. Foram utilizados modelos mistos para analisar a influĆŖncia nos fatores (posiĆ§Ć£o e estaĆ§Ć£o) e sua interaĆ§Ć£o. Os dados foram considerados aninhados em cada orientaĆ§Ć£o, dentro de cada Ć”rvore e de cada Ć”rea. A anĆ”lise estatĆ­stica foi realizada no software R com o pacote nlme. Dos Ć­ndices de vegetaĆ§Ć£o analisados, seis apresentaram dependĆŖncia da posiĆ§Ć£o/orientaĆ§Ć£o e estaĆ§Ć£o de coleta, sendo necessĆ”rio em posteriores estudos a obediĆŖncia de suas dependĆŖncias

    PCA3 molecular urine assay for prostate cancer: association with pathologic features and impact of collection protocols

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    IntroductionPCA3 is a non-coding mRNA molecule that is overexpressed in prostate cancer. The purpose of this study is to evaluate the utility of the PCA3 molecular urine test scores to predict adverse pathologic features and catheterized specimen collection.MethodsHundred men with clinically localized prostate cancer scheduled to undergo robotic prostatectomy were enrolled in the study following a standard consent process. The study protocol consisted of providing four urine samples. Voided urine obtained following digital rectal examination (DRE) pre-operatively (Vl), catheterized urine without DRE (V2), and l0-day and 6-week postoperative voided (V3 and V4) urine samples were collected and analyzed. These four urine specimens underwent target capture, transcription-mediated amplification, and hybridization in order to quantify both PCA3 and PSA mRNA. The PCA3 score was calculated as the ratio of PCA3 to PSA.ResultsInformative rates (sufficient mRNA for analysis) for VI, V2, V3 and V4 were 91, 85, 0 and 2%, respectively. There was no significant associations with pathological stage, Gleason score >6. Higher PCA3 scores at V1 correlated with increased risk for perineural invasion (P = 0.0479).ConclusionsInformative PCA3 scores can be obtained from post-DRE voided urine as well as catheterized urine without a DRE. The PCA3 test does not seem to predict adverse pathologic features, though, may have an association with perineural invasion. The ability of PCA3 score to predict clinical outcome remains to be determined

    Measurement of the B+ and B-0 lifetimes and search for CP(T) violation using reconstructed secondary vertices

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    The lifetimes of the B+ and B-0 mesons, and their ratio, have been measured in the OPAL experiment using 2.4 million hadronic Z(0) decays recorded at LEP. Z(0) --> b (b) over bar decays were tagged using displaced secondary vertices and high momentum electrons and muons. The lifetimes were then measured using well-reconstructed charged and neutral secondary vertices selected in this tagged data sample. The results aretau(B+) = 1.643 +/- 0.037 +/- 0.025 pstau(Bo) = 1.523 +/- 0.057 +/- 0.053 pstau(B+)/tau(Bo) = 1.079 +/- 0.064 +/- 0.041,where in each case the first error is statistical and the second systematic.A larger data sample of 3.1 million hadronic Z(o) decays has been used to search for CP and CPT violating effects by comparison of inclusive b and (b) over bar hadron decays, No evidence fur such effects is seen. The CP violation parameter Re(epsilon(B)) is measured to be Re(epsilon(B)) = 0.001 +/- 0.014 +/- 0.003and the fractional difference between b and (b) over bar hadron lifetimes is measured to(Delta tau/tau)(b) = tau(b hadron) - tau((b) over bar hadron)/tau(average) = -0.001 +/- 0.012 +/- 0.008

    A Measurement of Rb using a Double Tagging Method

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    The fraction of Z to bbbar events in hadronic Z decays has been measured by the OPAL experiment using the data collected at LEP between 1992 and 1995. The Z to bbbar decays were tagged using displaced secondary vertices, and high momentum electrons and muons. Systematic uncertainties were reduced by measuring the b-tagging efficiency using a double tagging technique. Efficiency correlations between opposite hemispheres of an event are small, and are well understood through comparisons between real and simulated data samples. A value of Rb = 0.2178 +- 0.0011 +- 0.0013 was obtained, where the first error is statistical and the second systematic. The uncertainty on Rc, the fraction of Z to ccbar events in hadronic Z decays, is not included in the errors. The dependence on Rc is Delta(Rb)/Rb = -0.056*Delta(Rc)/Rc where Delta(Rc) is the deviation of Rc from the value 0.172 predicted by the Standard Model. The result for Rb agrees with the value of 0.2155 +- 0.0003 predicted by the Standard Model.Comment: 42 pages, LaTeX, 14 eps figures included, submitted to European Physical Journal

    X-ray emission from the Sombrero galaxy: discrete sources

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    We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

    Performance of the CMS Cathode Strip Chambers with Cosmic Rays

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    The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

    A distinct role for B1b lymphocytes in T cell-independent immunity

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    Pathogenesis of infectious disease is not only determined by the virulence of the microbe but also by the immune status of the host. Vaccination is the most effective means to control infectious diseases. A hallmark of the adaptive immune system is the generation of B cell memory, which provides a long-lasting protective antibody response that is central to the concept of vaccination. Recent studies revealed a distinct function for B1b lymphocytes, a minor subset of mature B cells that closely resembles that of memory B cells in a number of aspects. In contrast to the development of conventional B cell memory, which requires the formation of germinal centers and T cells, the development of B1b cell-mediated long-lasting antibody responses occurs independent of T cell help. T cell-independent (TI) antigens are important virulence factors expressed by a number of bacterial pathogens, including those associated with biological threats. TI antigens cannot be processed and presented to T cells and therefore are known to possess restricted T cell-dependent (TD) immunogenicity. Nevertheless, specific recognition of TI antigens by B1b cells and the highly protective antibody responses mounted by them clearly indicate a crucial role for this subset of B cells. Understanding the mechanisms of long-term immunity conferred by B1b cells may lead to improved vaccine efficacy for a variety of TI antigens

    Lung epithelium as a sentinel and effector system in pneumonia ā€“ molecular mechanisms of pathogen recognition and signal transduction

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    Pneumonia, a common disease caused by a great diversity of infectious agents is responsible for enormous morbidity and mortality worldwide. The bronchial and lung epithelium comprises a large surface between host and environment and is attacked as a primary target during lung infection. Besides acting as a mechanical barrier, recent evidence suggests that the lung epithelium functions as an important sentinel system against pathogens. Equipped with transmembranous and cytosolic pathogen-sensing pattern recognition receptors the epithelium detects invading pathogens. A complex signalling results in epithelial cell activation, which essentially participates in initiation and orchestration of the subsequent innate and adaptive immune response. In this review we summarize recent progress in research focussing on molecular mechanisms of pathogen detection, host cell signal transduction, and subsequent activation of lung epithelial cells by pathogens and their virulence factors and point to open questions. The analysis of lung epithelial function in the host response in pneumonia may pave the way to the development of innovative highly needed therapeutics in pneumonia in addition to antibiotics
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