Problemas metodológicos na obtenção da curva de retenção da água pelo solo Methodological problems of the soil-water retention curve

Para estudar a variabilidade tanto metodológica quanto espacial da Curva de Retenção de Água no Solo, coletaram-se amostras de solo com estrutura indeformada à profundidade de 25 cm em uma área de Terra Roxa Estruturada Latossólica (Rhodic Kanhapludalf) em Piracicaba,SP. A amostragem obedeceu a um arranjo com espaçamento regular de cinco metros, resultando numa malha quadriculada de vinte e cinco linhas e dez colunas, totalizando duzentos e cinqüenta pontos. Elaboraram-se 250 Curvas de Retenção por secamento, utilizando-se as tensões de 5 x 10²; l x 10³; 6 x 10³; l x 10(4) Pa (Funil de Placa Porosa) e 3 x 10(4); 8 x 10(4); 3 x 10(5) e 1,5 x 10(6) Pa (Câmara de Pressão de Richards), totalizando oito pontos por curva. Analisou-se a variabilidade metodológica para os vários valores de tensão considerados, principalmente à luz da termodinâmica pertinente. Os resultados evidenciaram que os problemas analíticos são de tal ordem que podem levar a interpretações errôneas, comprometendo a qualidade de experimentos ou mesmo a comparabilidade de resultados provenientes de laboratórios diversos. Exemplificando, 43% das amostras apresentaram resultados inconsistentes, com valores de umidade à base de volume à 3x10(5) Pa menores que a 1,5x10(6) Pa, o que na prática poderia levar, dentre outros, a problemas de subestimativa nos valores de água disponível.<br>Undisturbed soil samples of a "Terra Roxa Estruturada Latossólica" (Rhodic Kanhapludalf) were taken in Piracicaba,SP from the 25 cm depth, in order to study both methodological and spatial variabilities of the soil water retention curve. The sampling followed a 5 m x 5 m grid of 10 columns and 25 Unes, resulting 250 collecting points. With these samples, 250 retention curves were obtained using porous plate funnels (tensions of 5 x 10²; 1 x 10³; 6 x 10³ and 1 x 10(4) Pa) and Richards pressure chambers (tensions of 3 x 10(4); 8 x 10(4); 3 x 10(5), and 1.5 x 10(6) Pa). The methodological variability was analyzed mainly in the light of the pertinent thermodynamics, using several values of tension. Results have shown that the analytical problems are such that they can lead to erroneous interpret rations, affecting the quality of the experiment and also the comparison of results from several laboratories. For instance, 43% of the samples showed non consistant results, with values of volumetric soil-water content smaller at the tension of 3 x 10(4) Pa than at the tension of 1.5 x 10(6) Pa, which, from the practical point of view, could, lead to subestimated values of available water

SARS-CoV-2 seroprevalence among the general population and healthcare workers in India, December 2020–January 2021

Background: Earlier serosurveys in India revealed seroprevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) of 0.73% in May–June 2020 and 7.1% in August–September 2020. A third serosurvey was conducted between December 2020 and January 2021 to estimate the seroprevalence of SARS-CoV-2 infection among the general population and healthcare workers (HCWs) in India. Methods: The third serosurvey was conducted in the same 70 districts as the first and second serosurveys. For each district, at least 400 individuals aged ≥10 years from the general population and 100 HCWs from subdistrict-level health facilities were enrolled. Serum samples from the general population were tested for the presence of immunoglobulin G (IgG) antibodies against the nucleocapsid (N) and spike (S1-RBD) proteins of SARS-CoV-2, whereas serum samples from HCWs were tested for anti-S1-RBD. Weighted seroprevalence adjusted for assay characteristics was estimated. Results: Of the 28,598 serum samples from the general population, 4585 (16%) had IgG antibodies against the N protein, 6647 (23.2%) had IgG antibodies against the S1-RBD protein, and 7436 (26%) had IgG antibodies against either the N protein or the S1-RBD protein. Weighted and assay-characteristic-adjusted seroprevalence against either of the antibodies was 24.1% [95% confidence interval (CI) 23.0–25.3%]. Among 7385 HCWs, the seroprevalence of anti-S1-RBD IgG antibodies was 25.6% (95% CI 23.5–27.8%). Conclusions: Nearly one in four individuals aged ≥10 years from the general population as well as HCWs in India had been exposed to SARS-CoV-2 by December 2020

Report from Working Group 2: Higgs Physics at the HL-LHC and HE-LHC

The discovery of the Higgs boson in 2012, by the ATLAS and CMS experiments, was a success achieved with only a percent of the entire dataset foreseen for the LHC. It opened a landscape of possibilities in the study of Higgs boson properties, Electroweak Symmetry breaking and the Standard Model in general, as well as new avenues in probing new physics beyond the Standard Model. Six years after the discovery, with a conspicuously larger dataset collected during LHC Run 2 at a 13 TeV centre-of-mass energy, the theory and experimental particle physics communities have started a meticulous exploration of the potential for precision measurements of its properties. This includes studies of Higgs boson production and decays processes, the search for rare decays and production modes, high energy observables, and searches for an extended electroweak symmetry breaking sector. This report summarises the potential reach and opportunities in Higgs physics during the High Luminosity phase of the LHC, with an expected dataset of pp collisions at 14 TeV, corresponding to an integrated luminosity of 3~ab$^{-1}$. These studies are performed in light of the most recent analyses from LHC collaborations and the latest theoretical developments. The potential of an LHC upgrade, colliding protons at a centre-of-mass energy of 27 TeV and producing a dataset corresponding to an integrated luminosity of 15~ab$^{-1}$, is also discussed

Search for new Higgs bosons via same-sign top quark pair production in association with a jet in proton-proton collisions at s=13TeV

A search is presented for new Higgs bosons in proton-proton (pp) collision events in which a same-sign top quark pair is produced in association with a jet, via the pp→tH/A→ttc‾ and pp→tH/A→ttu‾ processes. Here, H and A represent the extra scalar and pseudoscalar boson, respectively, of the second Higgs doublet in the generalized two-Higgs-doublet model (g2HDM). The search is based on pp collision data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 138fb−1. Final states with a same-sign lepton pair in association with jets and missing transverse momentum are considered. New Higgs bosons in the 200–1000 GeV mass range and new Yukawa couplings between 0.1 and 1.0 are targeted in the search, for scenarios in which either H or A appear alone, or in which they coexist and interfere. No significant excess above the standard model prediction is observed. Exclusion limits are derived in the context of the g2HDM