Performance of winter pasture species in different integrated crop-livestock systems in lowlands of Southern Brazil.

The introduction of winter forage species in succession to rice cropping in lowlands of Southern Brazil is an option for the productive system diversification..

De novo origins of multicellularity in response to predation

The transition from unicellular to multicellular life was one of a few major events in the history of life that created new opportunities for more complex biological systems to evolve. Predation is hypothesized as one selective pressure that may have driven the evolution of multicellularity. Here we show that de novo origins of simple multicellularity can evolve in response to predation. We subjected outcrossed populations of the unicellular green alga Chlamydomonas reinhardtii to selection by the filter-feeding predator Paramecium tetraurelia. Two of five experimental populations evolved multicellular structures not observed in unselected control populations within ~750 asexual generations. Considerable variation exists in the evolved multicellular life cycles, with both cell number and propagule size varying among isolates. Survival assays show that evolved multicellular traits provide effective protection against predation. These results support the hypothesis that selection imposed by predators may have played a role in some origins of multicellularity

Ecohealth trainer manual

This training manual, and the Field Building Leadership Initiative (FBLI) of which it is one component, is part of a global initiative to build capacity in ecosystem approaches to health. Although several books and journals provide materials for learners about Ecohealth, the FBLI Ecohealth Trainer Manual is intended primarily for lecturers, teachers, and trainers. The focus here is on how to teach Ecohealth, providing teachers and trainers with a starting point from which to explore, improvise, adapt, and develop diverse educational Ecohealth learning experiences for and with their participants

Les Espèces vègètales de couverture du sol destinées à la culture du coton en semis direct.

bitstream/item/142514/1/Les-especes-vegetables-de-couverture-du-sol....pdfCOTON-4

Alterations of cardiorespiratory and motor profile of paralympic 5-a-side football athletes during 14-week in-season training

The aim of this study was to characterize the cardiorespiratory and motor performance characteristics of blind 5-a-side footballers from the Brazilian Paralympic Team. Seven male athletes were evaluated at before and after 14-week in-season training (weekly volume between 6.5 hours to 10.8 hours), through cardiorespiratory fitness test, Agility test (5x10), Running-based Anaerobic Sprint Test (RAST) and Standing Long Jump Test (SLJT). The VO2max ranged from 51.9 (±3.8) to 54.3 (±5.0) mL.kg-1.min-1.VO2 at ventilatory threshold ranged from 48.4 (±4.4) to 41.1 (±6.8) mL.kg-1.min-1. Heart rate at ventilatory threshold ranged from 94.7 (±2.3) to 89.9 (±3.7) bpm. Regarding motor performance the values of medium Power Output ranged from 442 (± 63) to 421.9 (±66) Watts and Fatigue Index ranged from 63.1 (±9.4) to 53.9 (±14.8) W/s. Overall, our results show that while the performance of these athletes is inferior to that of professional players, their cardiorespiratory and motor performance is superior to that typical of semi-professional futsal athletes and, this study which can potentially suggest and contribute to the prescription of future training programs

Edge Contacts to Atomically Precise Graphene Nanoribbons.

Bottom-up-synthesized graphene nanoribbons (GNRs) are an emerging class of designer quantum materials that possess superior properties, including atomically controlled uniformity and chemically tunable electronic properties. GNR-based devices are promising candidates for next-generation electronic, spintronic, and thermoelectric applications. However, due to their extremely small size, making electrical contact with GNRs remains a major challenge. Currently, the most commonly used methods are top metallic electrodes and bottom graphene electrodes, but for both, the contact resistance is expected to scale with overlap area. Here, we develop metallic edge contacts to contact nine-atom-wide armchair GNRs (9-AGNRs) after encapsulation in hexagonal boron-nitride (h-BN), resulting in ultrashort contact lengths. We find that charge transport in our devices occurs via two different mechanisms: at low temperatures (9 K), charges flow through single GNRs, resulting in quantum dot (QD) behavior with well-defined Coulomb diamonds (CDs), with addition energies in the range of 16 to 400 meV. For temperatures above 100 K, a combination of temperature-activated hopping and polaron-assisted tunneling takes over, with charges being able to flow through a network of 9-AGNRs across distances significantly exceeding the length of individual GNRs. At room temperature, our short-channel field-effect transistor devices exhibit on/off ratios as high as 3 × 105 with on-state current up to 50 nA at 0.2 V. Moreover, we find that the contact performance of our edge-contact devices is comparable to that of top/bottom contact geometries but with a significantly reduced footprint. Overall, our work demonstrates that 9-AGNRs can be contacted at their ends in ultra-short-channel FET devices while being encapsulated in h-BN

Basic magnetic properties of magnetoactive elastomers of mixed content

The results of theoretical and experimental investigations of the polymer composites that belong to a class of magnetoactive elastomers with mixed magnetic content (MAEs-MC) are presented. The fundamental distinction of such composites from ordinary magnetoactive elastomers is that the magnetic filler of MAEs-MC comprises both magnetically soft (MS) particles of size 3-5 m and magnetically hard (MH) particles whose size is an order of magnitude greater. Since MH particles of the magnetic filler are mixed into a composition in a non-magnetised state, this can ensure preparation of samples with fairly homogeneous distribution of the filler. The 'initiation' process of a synthesised MAE-MC is done by its magnetisation in a strong magnetic field that imparts to the sample unique magnetic and mechanical properties. In this work, it is shown that the presence of MS particles around larger MH particles, firstly, causes an augmentation of magnetic moments, which the MH particles acquire during initiation, and secondly, enhances the magnetic susceptibility and remanent magnetisation of MAEs-MC. These magnetic parameters are evaluated on the basis of the macroscopic magnetostatics from the experimental data of spatial scanning of the field over the space around MAEs-MC made in the shape of a spheroid. A set of samples with a fixed MH and varying MS volume contents that are initiated in two different fields, is used. The developed mesoscopic model of magnetic interactions between the MH and MS phases is able to explain the experimentally observed dependencies of the magnetic parameters on the concentration of the MS phase. The problem is solved numerically under the assumption that the elastic matrix of MAEs-MC is rigid, i.e. the mutual displacements of the particles are negligible. The model helps to elucidate the interaction of the magnetic phases and to establish that the MS phase plays thereby a dual role. On the one hand, the MS phase screens out the field acting inside MH particles, and on the other hand, it forms mesoscopic magnetic bridges between adjoining MH particles, which in turn enhance their field. The combined interplay of these contributions defines the resulting material properties of MAEs-MC on the macroscopic scale. © 2020 The Author(s). Published by IOP Publishing Ltd

Influência do espaçamento entre linhas e da relação entre espaçamento-altura na podridão de maçãs do algodoeiro.

A podridão de maçãs é um dos problemas fitossanitários mais importantes para a cultura do algodoeiro no Brasil. Sob condições de elevada umidade e precipitação pluviométrica no período de abertura ou formação das maçãs, essa enfermidade provoca prejuízos expressivos. A podridão de maçãs pode ocorrer tanto antes como após sua abertura, e é caracterizada pela ação de um complexo de agentes patogênicos primários e secundários, sendo registra dos mais de uma centena de microrganismos associados

The Efficacy of Vaginal Clindamycin for the Treatment of Abnormal Genital Tract Flora in Pregnancy

Objective: To assess the efficacy of 2% clindamycin vaginal cream (CVC) to treat bacterial vaginosis (BV) in pregnancy. Methods: A prospective, randomized, double-blind, placebo-controlled, tricenter study. Four hundred and four women with BV on Gram stain at their first antenatal clinic visit were randomized to receive a 3-day course of 2% CVC or placebo. The outcome was assessed using an intention to treat analysis at 3 weeks and 6 weeks post-treatment according to three different diagnostic methods based on five criteria (Gram stain and all four elements of clinical composite criteria: vaginal discharge, abnormal vaginal pH, clue cells, amine odor), three criteria (vaginal pH, clue cells, amine odor) or two criteria (clue cells and amine odor) to reflect stringency of diagnosis, historical precedence and government agency recommendations respectively. Results: Using five diagnostic criteria, 18% of CVC patients were cured and 70.8% either cured and/or improved compared to 1.6% and 12% of placebo patients respectively (p < 0.0001). Using three diagnostic criteria, 44.8% of CVC patients were cured and 77.3% were either cured and/or improved compared to 9.3% and 28.8% of placebo patients respectively (p < 0.0001). Using two diagnostic criteria, 75.0% of CVC patients were cured compared to 18.0% of placebo patients (p < 0.0001). Recurrence rates in those CVC patients successfully treated were approximately 6% at 6 weeks post baseline and 10% at 28 to 34 weeks gestation. Conclusions: A 3-day course of CVC appears to be well tolerated by the mother and statistically significantly more efficacious than placebo in the treatment of BV during the second trimester of pregnancy

Avaliação da intensidade do treinamento técnico-tático e da fadiga causada em jogadores de futebol da categoria sub-20

Resumo Visto que o calendário atual do futebol não disponibiliza um tempo hábil para a devida recuperação dos atletas, fadiga e recuperação têm sido amplamente estudadas por pesquisadores. O que levou ao surgimento de alguns instrumentos com o propósito de fornecer informações e dar suporte aos profissionais visando a alta performance. O objetivo deste estudo foi analisar a intensidade do Treinamento Técnico-tático e a fadiga causada em jogadores de futebol da categoria sub-20, através do desempenho em testes de salto vertical e horizontal e da percepção subjetiva de esforço da sessão (PSE da sessão). Os jogadores (n = 25) realizaram o salto vertical contra movimento (SCM) e horizontal (SH), antes e após a uma sessão de Treinamento Técnico-tático (TTT), sendo a intensidade avaliada pela Escala de Borg (CR 10). O SCM não apresentou diferença significativa (p > 0,05), enquanto que o SH foi maior no Pós-TTT em relação ao Pré-TTT (p = 0,02). Quanto a PSE da sessão, 92% dos jogadores classificaram a intensidade do TTT como sendo de fácil à moderada. Os resultados deste estudo indicam que o TTT de baixa intensidade não compromete a potência nos testes de salto vertical e horizontal. Sugere-se que além de proporcionar a operacionalização dos padrões de comportamento táticos coletivos, o TTT de baixa intensidade possa ser utilizado em treinamentos de caráter regenerativo ou em momentos que o calendário esportivo não possibilite a recuperação completa dos jogadores