Measurement of the ttbar Production Cross Section in ppbar Collisions at sqrt(s)=1.96 TeV using Lepton + Jets Events with Lifetime b-tagging

We present a measurement of the top quark pair ($t\bar{t}$) production cross section ($\sigma_{t\bar{t}}$) in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV using 230 pb$^{-1}$ of data collected by the D0 experiment at the Fermilab Tevatron Collider. We select events with one charged lepton (electron or muon), missing transverse energy, and jets in the final state. We employ lifetime-based b-jet identification techniques to further enhance the $t\bar{t}$ purity of the selected sample. For a top quark mass of 175 GeV, we measure $\sigma_{t\bar{t}}=8.6^{+1.6}_{-1.5}(stat.+syst.)\pm 0.6(lumi.)$ pb, in agreement with the standard model expectation.Comment: 7 pages, 2 figures, 3 tables Submitted to Phys.Rev.Let

FATIGUE-INDUCED CHANGES IN KNEE KINEMATICS AND MUSCLE FORCES IN PROFESSIONAL HANDBALL-SPECIFIC TASK

This study investigated the impact of fatigue on knee kinematics and muscle forces in female handball athletes performing sidestep-cutting manoeuvres. Twenty athletes completed six trials, each divided equally before and after a handball-specific fatigue protocol. Kinematic and kinect data were gathered using an infrared motion capture system and a force plate. Analysis was performed with OpenSim 3.3. The results were compared using statistical parametric mapping. They indicated significant fatigue-related decreases in knee flexion during the early stance phase, reduced activity in the vastus intermedius and medialis muscles. Therefore, the findings indorms the design of programs focused on improving muscle endurance; however, there is still no conclusive evidence linking fatigue to an increased risk of knee load

EFFECT OF FATIGUE ON TRUNK- AND HIP-KNEE COORDINATION DURING SIDESTEP CUTTING MANEUVER IN HANDBALL ATHLETES

This study investigated how fatigue impacts trunk-hip and hip-knee coordination in female handball athletes during the sidestep cutting maneuver (SCM). Twenty participants performed three trials of the SCM task under pre- and post-fatigue conditions. An eight-camera motion capture system tracked reflective markers attached to their skin to compute the trunk, hip, and knee angles. A vector coding technique evaluated coordination patterns. Results indicated that while trunk-knee coordination remained unaffected by fatigue, significant changes were observed in the hip-knee coordination within the transversal plane post-fatigue. These findings highlight the need for customized training that considers possible joint changes caused by fatigue

Search for W' bosons decaying to an electron and a neutrino with the D0 detector

This Letter describes the search for a new heavy charged gauge boson W' decaying into an electron and a neutrino. The data were collected with the D0 detector at the Fermilab Tevatron proton-antiproton Collider at a center-of-mass energy of 1.96 TeV, and correspond to an integrated luminosity of about 1 inverse femtobarn. Lacking any significant excess in the data in comparison with known processes, an upper limit is set on the production cross section times branching fraction, and a W' boson with mass below 1.00 TeV can be excluded at the 95% C.L., assuming standard-model-like couplings to fermions. This result significantly improves upon previous limits, and is the most stringent to date.Comment: submitted to Phys. Rev. Let

Reproduction of the blue jack mackerel, Trachurus picturatus, in western Portugal: microscopic gonad analysis reveals indeterminate fecundity and skipped spawning patterns

Blue jack mackerel, Trachurus picturatus, is the fifth most landed fish species in mainland Portugal, but information on its reproductive biology is scarce. From September 2018 to August 2019, 626 specimens were collected from commercial vessels to clarify the reproductive strategy of the T. picturatus population off the west coast of Portugal. The proportion and length range of males and females were similar. Only three of the specimens collected were categorized as immature, indicating that the fish caught in the fishery are primarily mature. The spawning season lasted from late January until the end of March, with gonadosomatic indices being similar for males and females. Fecundity was indeterminate, and estimated batch fecundity ranged between 6,798 (at 25.4 cm TL) and 302,358 oocytes (at 33.8 cm TL). The low number of females showing direct evidence of imminent or recent spawning suggests a low number of spawning events. In addition, 12.7% of females were considered non-reproductive due to ovary abnormalities including parasitic infection by Kudoa species, atretic structures and skipped spawning events. This study highlights the importance of accounting for skipped spawning events and ovary abnormalities in the management of species fisheries.info:eu-repo/semantics/publishedVersio

Sorption and desorption of picloram in soils under pastures in Brazil

The objective of this work was to determine the coefficients of sorption and desorption of picloram in Ultisol (PVA) and Oxisol (LVA), displaying different physical and chemical characteristics. Samples of soil were collected at the 0 20 cm depth in degraded pasture areas in Viçosa-MG. Firstly, the equilibrium time between the herbicide in solution and the herbicide which was sorbed in the soil was determined by the Batch Equilibrium method. The time required was 24 hours. Sorption and desorption studies were carried out under controlled laboratory conditions; the sorption evaluation consisted in adding 10.0 mL of herbicide solutions at different concentrations to tubes containing 2.00 g of soil, with vertical rotary agitation being maintained during the pre-determined equilibrium time. After centrifugation, supernatant extract cleaning and filtration, herbicide concentration was determined by high performance liquid chromatography (HPLC) with UV detection at 254 nm. Desorption was evaluated using the samples in the tubes after the sorption tests. The Freundlich model was used for interpretation of the sorption process. Ultisol showed higher adsorption coefficient (Kf a) compared with Oxisol, which may be attributed to the lower pH of the soil and its higher organic matter content. Desorption process occurred in both soils; the LVA allowed greater release of the previously sorbed molecules.Objetivou-se com este trabalho determinar os coeficientes de sorção e dessorção do picloram em Argissolo Vermelho-Amarelo (PVA) e Latossolo Vermelho-Amarelo (LVA) com diferentes características físico-químicas. As amostras desses solos foram coletadas na profundidade de 0 20 cm em áreas de pastagens degradadas, na região de Viçosa, MG. Primeiramente, determinou-se o tempo de equilíbrio entre o herbicida em solução e aquele que ficou sorvido no solo, por meio do método "Batch Equilibrium". O tempo necessário foi 24 h. Os estudos de sorção e dessorção foram realizados sob condições laboratoriais controladas; a avaliação da sorção consistiu em adicionar 10,0 mL de solução do herbicida com diferentes concentrações em tubos contendo 2,00 g de solo, permanecendo sob agitação rotatória vertical pelo tempo de equilíbrio predeterminado. Após centrifugação, limpeza do extrato sobrenadante e filtração, a concentração do herbicida foi determinada por cromatografia líquida de alta eficiência (CLAE), com detector UV a 254 nm. A dessorção foi avaliada utilizando as amostras contidas nos tubos, após os ensaios de sorção. O modelo de Freundlich foi utilizado para a interpretação do processo sortivo. O Argissolo Vermelho-Amarelo apresentou maior coeficiente de sorção (Kf a) quando comparado com o Latossolo Vermelho-Amarelo, o que pode ser atribuído ao menor pH deste solo e ao seu maior teor de matéria orgânica. O processo de dessorção ocorreu em ambos os solos; o LVA permitiu maior liberação das moléculas anteriormente sorvidas

Efeito de diferentes reguladores de crescimento na regeneração in vitro de pau-rosa (Aniba rosaeodora Ducke)

O objetivo deste trabalho foi estabelecer um protocolo para a regeneração in vitro de pau-rosa (Aniba rosaeodora Ducke), utilizando brotações apicais e segmentos nodais inoculados em meio de cultura com distintas concentrações de diferentes reguladores de crescimento. Explantes esterilizados com soluções de benomyl (4,0 g.L-1) por 24 horas e hipoclorito de sódio a 20% + tween 20 por 20 minutos, foram submetidos a um experimento de indução de broto, raiz e calo em meio MS1 acrescido de 30g.L-1 de sacarose e 9g.L-1 de agar, suplementado com BAP (0,0 e 4,0 mg.L-1), ANA, AIA e 2,4-D (0,0; 3,0 e 6,0 mg.L-1), e suas respectivas combinações. O delineamento utilizado foi o inteiramente casualizado em esquema fatorial 7 X 2, com 14 tratamentos e 15 repetições cada, onde foram analisados o número médio de brotos, raízes e calo. Após 90 dias, os resultados mostraram que a presença de auxinas é fundamental para a formação dos parâmetros induzidos nos explantes de pau-rosa. O meio de cultura contendo 4,0 mg.L-1 de BAP + 6,0 mg.L-1 de AIA apresentou a melhor média para a brotação com 2,13 brotos/explante. Para o enraizamento o meio contendo 3,0 mg.L-1 de ANA foi o mais eficiente, apresentando uma média de 2,53 raízes/explante. Em relação à indução de calo, todos os tratamentos apresentaram calogênese, porém o meio suplementado com 4,0 mg.L-1 de BAP + 6,0 mg.L-1 de 2,4-D, apresentou a melhor média, 1,67 calos/explante