Th2 cells are less susceptible than Th1 cells to the suppressive activity of CD25+ regulatory thymocytes because of their responsiveness to different cytokines

AbstractT-cell clones generated from both CD4+CD25+ and CD8+CD25+ human thymocytes were assessed for their ability to suppress the proliferative response to allogeneic stimulation of type 1 T-helper (Th1) or type 2 T-helper (Th2) clones derived from autologous CD4+CD25- thymocytes. Both CD4+ and CD8+ T-regulatory (Treg) cells completely suppressed the proliferation of Th1 clones but exhibited significantly lower suppressive activity on the proliferation of Th2 clones. The partial suppressive effect on Th2 cells was further reduced by the addition in culture of interleukin-4 (IL-4), whereas it was increased in the presence of an anti–IL-4 monoclonal antibody (mAb). The suppressive activity on Th2 clones was also completely inhibited by the addition of IL-7, IL-9, and IL-15 but not of IL-2, whereas the suppressive effect on Th1 clones was only reverted by the addition of IL-15. Of note, Th2 clones expressed significantly higher amounts of mRNA for IL-4 receptor (IL-4R) and IL-9R α chains than Th1 clones, whereas the expression of mRNA for IL-2R, IL-7R, and IL-15R α chains was comparable. Taken together, these findings demonstrate that Th2 cells have a lower susceptibility than Th1 cells to the suppressive activity of human CD25+ regulatory thymocytes, because they are able to produce, and to respond to, growth factors distinct from IL-2, such as IL-4 and IL-9. (Blood. 2004; 103:3117-3121

Search for anomalous production of events with three or more leptons in pp collisions at √s = 8TeV

Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published articles title, journal citation, and DOI.A search for physics beyond the standard model in events with at least three leptons is presented. The data sample, corresponding to an integrated luminosity of 19.5fb-1 of proton-proton collisions with center-of-mass energy s=8TeV, was collected by the CMS experiment at the LHC during 2012. The data are divided into exclusive categories based on the number of leptons and their flavor, the presence or absence of an opposite-sign, same-flavor lepton pair (OSSF), the invariant mass of the OSSF pair, the presence or absence of a tagged bottom-quark jet, the number of identified hadronically decaying τ leptons, and the magnitude of the missing transverse energy and of the scalar sum of jet transverse momenta. The numbers of observed events are found to be consistent with the expected numbers from standard model processes, and limits are placed on new-physics scenarios that yield multilepton final states. In particular, scenarios that predict Higgs boson production in the context of supersymmetric decay chains are examined. We also place a 95% confidence level upper limit of 1.3% on the branching fraction for the decay of a top quark to a charm quark and a Higgs boson (t→cH), which translates to a bound on the left- and right-handed top-charm flavor-violating Higgs Yukawa couplings, λtcH and λctH, respectively, of |λtcH|2+|λctH|2<0.21

Measurement of associated W plus charm production in pp collisions at √s=7 TeV

Peer reviewe

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores

A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació

Evaluation of Probabilistic Site-Specific Seismic-Hazard Methods and Associated Uncertainties, with Applications in the Po Plain, Northern Italy

Site-specific ground motion hazard assessed by a PSHA one-step approach that handles a single-site sigma and its uncertainties and uses a simple logic tree, is compared with a two-step approach that includes bedrock motion evaluation and wave propagation through a local soil profile with consideration of the main epistemic uncertainties. The one-step analysis relies on accelerometer data from the Po Plain, a sedimentary basin in Northern Italy where an earthquake sequence with two Mw ~6.0 events occurring in 2012 was extensively recorded. UH spectra on soil and exposed bedrock are evaluated at three deep-soil accelerometer sites (MRN, NVL and T0821), using residual measures available from other studies, by which uncertainties in site terms (S2S) and single-site sigma (ss,s) are estimated. Despite similarity in geologic conditions, at least one out of three sites displays in the one-step analysis substantial differences in mean level (T0821) or in the (84-16) percentile spread (NVL), depending on differences in site terms and single-site sigma, possibly caused by source-to site propagation effects. The two-step approach was applied to the single MRN site using as excitation carefully selected and broadband-matched acceleration signals and linear, equivalent-linear and nonlinear approaches in propagation analyses, finding that assumptions on soil degradation curves dominate the variability of results. The linear approach provided the best results, based on: (i) the similarity of the one-step non-ergodic UHS with the two-step result based on the linear approach; (ii) the comparison with observed records at MRN during the 2012 sequence mainshocks, showing PGA and short period spectral levels well beyond those predicted by different non-linear assumptions; (iii) a similar evidence from a set of 21 stations at deep soil sites of the Japanese Kik-net

Adaptação de um código computacional de escoamentos incompressíveis 3-D para problemas com superfície livre

Neste trabalho, apresenta-se a adaptação de um código computacional de simulação numérica de escoamentos incompressíveis tridimensionais (FLUINCO) para tratar problemas com superfície livre. É adotada uma descrição arbitrária lagrangeana euleriana (ALE), onde o movimento da malha é realizado através de um esquema de suavização das velocidades. O algoritmo, desenvolvido em FORTRAN, baseia-se no Método dos Elementos Finitos (MEF). As equações diferenciais governantes do fluido são discretizadas no tempo e no espaço por um método semi-implícito de Taylor-Galerkin de dois passos usando elementos tetraédricos lineares. É analisado o problema do escoamento sobre um canal com uma depressão trapezoidal no fundo (trench) e os resultados são comparados com os obtidos por outros autores