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Abstract The kagome lattice is an exciting solid state physics platform for the emergence of nontrivial quantum states driven by electronic correlations: topological effects, unconventional superconductivity, charge and spin density waves, and unusual magnetic states such as quantum spin liquids. While kagome lattices have been realized in complex multi-atomic bulk compounds, here we demonstrate from first-principles a process that we dub kagomerization, in which we fabricate a two-dimensional kagome lattice in monolayers of transition metals utilizing an hexagonal boron nitride (h-BN) overlayer. Surprisingly, h-BN induces a large rearrangement of the transition metal atoms supported on a fcc(111) heavy-metal surface. This reconstruction is found to be rather generic for this type of heterostructures and has a profound impact on the underlying magnetic properties, ultimately stabilizing various topological magnetic solitons such as skyrmions and bimerons. Our findings call for a reconsideration of h-BN as merely a passive capping layer, showing its potential for not only reconstructing the atomic structure of the underlying material, e.g. through the kagomerization of magnetic films, but also enabling electronic and magnetic phases that are highly sought for the next generation of device technologies.

ABSTRACT: Abiotic stresses, such as heat, drought and salinity, affect the development of wheat crop and hinder its expansion to the central region of Brazil. The identification of genotypes tolerant to these conditions is important for improving yield performance. The present research evaluated the impact of different abiotic stresses on germination and seedling development and selected wheat genotypes tolerant to these stresses, using multi-trait analysis. Heat, drought and salinity stresses were induced in seeds of 23 wheat genotypes. Seed germination, seedling length and dry mass were evaluated. An adaptability and stability model and a multi-trait selection index were applied to the data. Drought and salinity negatively affected the development of seedlings of the 23 evaluated genotypes. However, the VI 14055, ORS Madre Pérola and BRS 404 genotypes conferred the best adaptability and stability results and were selected by the MGIDI, which revealed that great performance can be achieved in regions with potential for abiotic stress, in the early stages of development.

The field of orbitronics has emerged with great potential to impact information technology by enabling environmentally friendly electronic devices. The main electronic degree of freedom at play is the orbital angular momentum, which can give rise to a myriad of phenomena such as the orbital Hall effect (OHE), torques and orbital magnetoelectric effects. Here, we explore via realistic time-dependent electronic structure simulations the magnetic response of a non-magnetic material, an ultrathin Pt film, to ultrafast laser pulses of different polarizatons and helicities. We demonstrate the generation of significant orbital and spin magnetizations and identify the underlying mechanisms consisting of the interplay of the OHE, inverse Faraday effect and spin-orbit interaction. Our discoveries advocate for the prospect of encoding magnetic information using light in materials that are not inherently magnetic.

Adequar metodologias que possibilitem avaliar o vigor das sementes de lentilha é de suma importância para garantir a comercialização de lotes com ótimo desempenho em campo. Objetivou-se definir as condições adequadas para a realização do teste de condutividade elétrica para classificação de lotes quanto ao vigor, como também avaliar se a atividade de enzimas antioxidantes possui relação com o potencial fisiológico das sementes de lentilha. Para tanto, sementes de sete lotes cv. Silvina foram submetidos a diferentes testes para a caracterização da sua qualidade inicial e os resultados comparados com os obtidos no teste de condutividade elétrica e atividade enzimática. Foram utilizados para avaliar a condutividade elétrica quatro períodos de embebição (4, 8, 12 e 24 h), combinados com três volumes de água (75, 100 e 150 mL) sob temperatura de 25 °C. Foram realizadas também a avaliação das enzimas SOD, CAT e APX. O teste de condutividade elétrica e o de atividade enzimática foram eficientes para a avaliação do potencial fisiológico com informações relacionadas com outros testes de vigor. O teste de condutividade elétrica conduzido com 50 sementes imersas em 75 mL de água, a 25 °C, por 24 h permite a separação dos lotes em níveis de vigor. A atividade das enzimas CAT, SOD e APX pode ser relacionada ao potencial fisiológico das sementes de lentilha.

Na região semiárida do Nordeste brasileiro é comum a ocorrência de variação temporal e espacial de chuvas, resultando em limitações hídricas que afetam a produção, especialmente do algodoeiro. Nesse sentido, a quitosana pode ser uma estratégia para minimizar os efeitos do déficit hídrico, melhorando a absorção de água e nutrientes. Objetivou-se com este estudo avaliar o efeito de concentrações de quitosana como atenuante da restrição hídrica no cultivo do algodoeiro de fibra naturalmente colorida ‘BRS Jade’. As plantas foram conduzidas em lisímetros de drenagem sob condições de casa de vegetação. Utilizou-se o delineamento inteiramente casualizado em esquema fatorial 2 × 4, sendo duas lâminas de irrigação (100 e 50% da necessidade hídrica da cultura) e quatro concentrações de quitosana (0,0; 0,25; 0,50 e 0,75 g L-1) com três repetições e uma planta por parcela. A restrição hídrica em 50% da lâmina reduziu o conteúdo relativo de água, a síntese de pigmentos fotossintéticos e a massa de algodão em caroço. Entretanto, a aplicação foliar de quitosana entre as concentrações de 0,25 e 0,50 g L-1 amenizou os efeitos deletérios da restrição hídrica sobre o teor de clorofila b, carotenoides, diâmetro do caule, área foliar, peso de 100 sementes, peso médio de capulho, massa de algodão em caroço, fitomassa seca total de capulhos, fitomassa seca do caule, da folha e da parte aérea do algodoeiro de fibra colorida ‘BRS Jade’.

ABSTRACT: Near-infrared (NIR) spectroscopy is a promising tool for optimizing seed analyses quickly and assertively. The aim of this study was to investigate the viability of NIR in association with chemometric methods in classification of soybean seed lots regarding their physiological potential. We evaluated 372 soybean seed lots for vigor and obtained NIR spectra from seed samples. The original spectra were pre-processed by the following methods: Standard Normal Variate (SNV), SNV + 1st and 2nd derivatives, Gap-segment derivative, and Savitzky-Golay for the first- and second-degree derivatives, as well as combinations of the methods. The lots were divided into Class I (≥ 85% germination after accelerated aging) and Class II (< 85% germination after accelerated aging); and the pre-processed spectra were used to build classification models through the following methods: K-nearest neighbors (KNN), Partial Least Squares - Discriminant Analysis (PLS-DA), Naive Bayes (NB), Random Forest (RF), and Support Vector Machine (SVM). The PLS-DA model showed greater classification accuracy and kappa, followed by SVM. The lowest accuracy values were obtained for the NB and RF models. The regions between the wavelengths 1,000-1,200 nm and 2,200-2,500 nm were the most important for distinguishing the quality levels of soybean seeds.

Abstract The phase of the quantum-mechanical wave function can encode a topological structure with wide-ranging physical consequences, such as anomalous transport effects and the existence of edge states robust against perturbations. While this has been exhaustively demonstrated for electrons, properties associated with the elementary quasiparticles in magnetic materials are still underexplored. Here, we show theoretically and via inelastic neutron scattering experiments that the bulk ferromagnet Mn5Ge3 hosts gapped topological Dirac magnons. Although inversion symmetry prohibits a net Dzyaloshinskii-Moriya interaction in the unit cell, it is locally allowed and is responsible for the gap opening in the magnon spectrum. This gap is predicted and experimentally verified to close by rotating the magnetization away from the c-axis with an applied magnetic field. Hence, Mn5Ge3 realizes a gapped Dirac magnon material in three dimensions. Its tunability by chemical doping or by thin film nanostructuring defines an exciting new platform to explore and design topological magnons. More generally, our experimental route to verify and control the topological character of the magnons is applicable to bulk centrosymmetric hexagonal materials, which calls for systematic investigation.

The use of high-quality Urochloa decumbens seeds is an essential factor for the establishment of pastures, and osmopriming under stress conditions may improve seed performance. This study was conducted at the Universidade Federal de Viçosa in a completely randomized design and aimed to evaluate the effects of osmopriming and its relationship with physical and physiological attributes of U. decumbens seeds subjected to water deficit. Seeds from ten lots were primed in H2O (0 MPa) and PEG (−0.8 MPa), KNO3 (0.2%), and SNP (0.10 mmol L−1) solutions for 24 hours. Unprimed seeds were used as control. The seeds were evaluated in two trials after osmopriming. Trial I consisted of the X-ray test to evaluate physical attributes and germination and vigor tests. In Trial II, the seeds were placed to germinate under favorable (0 MPa) and water deficit conditions (−0.2 MPa) to evaluate physiological attributes. In general, osmopriming of U. decumbens seeds assisted in increasing physical attributes such as area, gray scale, perimeter, and tissue density. Osmopriming does not contribute to the best physiological performance of U. decumbens seeds under ideal germination conditions (0 MPa). However, osmopriming with SNP (0.10 mmol L−1) and PEG (−0.8 MPa) for 24 hours contributes to the better physiological performance of seeds under water deficit.

Abstract: The demand for techniques that make it possible to assess the physiological potential of seeds quickly and assertively make near-infrared spectroscopy (FT-NIR) and seedling analysis using ILASTIK software promising tools. The aim of this study was to evaluate the physiological potential of Urochloa decumbens seeds using near-infrared spectroscopy (FT-NIR) and ILASTIK software. Seeds from 10 lots of U. decumbens were classified according to their physiological potential (germination and vigor) and then FT-NIR spectra were obtained from individual seed samples, the original spectra being pre-processed with different dispersion correction methods used for the construction of a classification model through partial least squares discriminant analysis (PSL-DA). For the ILASTIK evaluation, the seedlings were photographed at 7 and 14 days of germination and the trained classifier was applied to the images, generating data on the numbers of strong seedlings, weak seedlings and non-germinated seeds. With data from the FT-NIR technique pre-processed by the 2nd derivative of Savitzky-Golay, it was possible to obtain a classification model with high efficiency to discriminate the classes regarding the physiological potential of the seeds. ILASTIK was efficient to classify seeds according to their physiological potential after only 7 days of germination. FT-NIR and ILASTIK analyses are non-destructive and fast alternatives, with great potential for quality control of U. decumbens seed lots.

The logging intensity often does not take into account the spatial heterogeneity of the forest volume of commercial native species in the Brazilian Amazon. This study aims to evaluate the spatio-temporal heterogeneity distribution by assessing logging intensity and its effects on the volumetric stock and abundance of commercial species, with a focus on sustainable management practices. This study was conducted in the Saracá-Taquera National Forest in the Brazilian Amazon. Forest inventory data, elevation, and PlanetScope satellite images were integrated into a geographic information system. The information was aggregated into regular 1-hectare cells for the times before, during, and after logging (t0, t1, and t2). The unsupervised classification algorithm k-means with four clusters was used to analyze heterogeneity. Before logging, areas with higher commercial volumes were distant from water bodies, while areas with lower elevation had lower wood stocks. Logging intensity was generally low, concentrating on a few trees per hectare. Logging in the study area revealed a heterogeneous spatial distribution by intensifying in areas with the highest wood stocks. These results suggest that, in addition to the recommended logging intensity according to legislation, forest heterogeneity should be considered by the manager, promoting adaptive strategies to ensure the conservation of forest resources.

The COVID-19 pandemic represented a huge obstacle for public health and demonstrated weaknesses in surveillance and health promotion systems around the world. Its etiological agent, SARS-CoV-2, of zoonotic origin, has been the target of several studies related to the control and prevention of outbreaks and epidemics of COVID-19 not only for humans but also for animals. Domestic animals, such as dogs and cats, have extensive contact with humans and can acquire the infection both naturally and directly from humans. The objective of this article was to summarize the seroprevalence findings of SARS-CoV-2 in dogs and cats and correlate them with the strength of infection risk between each of them. This is a systematic review and meta-analysis following the recommendations of PRISMA 2020. The search and selection of papers was carried out using in vivo experimental works with animals using the descriptors (MeSH/DeCS) “Animal”, “Public Health”, “SARS-CoV-2” and “Pandemic” (together with AND) in English, Portuguese or Spanish for Science Direct, PUBMED, LILACS and SciELO databases. The ARRIVE checklist was used for methodological evaluation and the Comprehensive Meta-Analysis v2.2 software with the Difference Risk (RD) test to evaluate statistical inferences (with subgroups by continent). Cats showed greater susceptibility to SARS-CoV-2 compared to dogs both in a joint analysis of studies (RD = 0.017; 95% CI = 0.008–0.025; p < 0.0001) and in the American subgroup (RD = 0.053; 95% CI = 0.032–0.073; p < 0.0001), unlike the lack of significant difference on the European continent (RD = 0.009; 95% CI = −0.001–0.018; p = 0.066). Therefore, it was observed that cats have a greater interest in health surveillance due to the set of biological and ecological aspects of these animals, but also that there are a set of factors that can influence the spread and possible spillover events of the virus thanks to the anthropozoonotic context.

ABSTRACT Tephrosia egregia Sandwith is a species that develops in some States of the Northeast region of Brazil. It is propagated by seeds and has considerable potential for restoration. Thus, studies related to seed germination are important for the species. The aims were to characterize the post-seminal development and evaluate the germination response of the seeds under different temperatures and water stress and salt stress. Germination tests were performed at 20, 25, 30 and 20-30 °C and under PEG 6000 and NaCl concentrations (-0.2, -0.4, -0.6 and -0.8 MPa). The germination test should be conducted in a paper roll at 25 ºC for 14 days. Seed germination declines from the water potential of -0.2 MPa on; the species is sensitive to water stress. Under salt stress, there is more accentuated decline in germination as from -0.4 MPa, and this is an indication have a certain tolerance to salinity.

A ausência de estudos geográficos sobre os espaços das minorias, incluindo os surdos, é uma lacuna evidente na análise da cidade brasileira atual. Este artigo objetiva apresentar algumas características da espacialidade dos surdos ao longo do tempo a partir de um levantamento bibliográfico sobre a história desses sujeitos e da elaboração de uma breve historicização. Com isso, será possível compreender que os surdos estiveram por muito tempo restritos à casa, aos clubes de surdos e escolas e, nos atuais dias, há uma busca progressiva por promover a verdadeira inclusão dos surdos e deficientes auditivos na cidade. Nos últimos anos do século XX, os surdos vêm se organizando e se fortalecendo socialmente por meio das políticas de acessibilidade e inclusão, presentes na pauta de debate local, nacional e internacional. Sendo assim, a mobilização desse grupo por direitos manifesta-se em diferentes frentes, inclusive na reivindicação de viver a cidade. Ao contrário das realidades enfrentadas pelos surdos em tempos passados, quando a surdez era considerada uma deficiência incapacitante, acentuando-se a exclusão social deste grupo, é possível compreender, através da historicização apresentada, a busca (desses sujeitos) pela identificação e superação das barreiras, ainda presentes nas cidades, que dificultam seus fluxos, interferindo na sua liberdade de ir e vir, impeditivas da realização de seus desejos. Este artigo constitui-se num recorte de pesquisa de doutorado, que teve como tema central discutir a cidade como um espaço deficiente para atender às necessidades de pessoas surdas, em suas múltiplas faces.

Abstract: The search for techniques that allow for the rapid and accurate assessment of seed vigor, such as the Seedling Analysis System (SAPL®) and ILASTIK®, can be promising alternatives for seedling image analysis. The objective of this work was to classify the vigor of lentil seeds using seedling image analysis techniques and interactive machine learning. Seeds from seven lots were characterized for physiological potential through germination and vigor tests. For computerized seedling analysis, the seeds were subjected to seedling growth tests at 20 °C for three, four, five, and ten days, and then photographed using a digital camera. The images were processed using SAPL® software, yielding values for total length, root length, shoot length, and vigor, growth, and uniformity indices. ILASTIK® provided data on the percentage of vigorous seedlings, non-vigorous seedlings, and dead seeds. The total length of seedlings, root length, shoot length, and vigor indices determined at 4 days of germination by SAPL® allowed for the classification of lots in terms of vigor. Data obtained by ILASTIK® at 4 days of germination, used in machine learning studies, enable the development of models with high accuracy for seed vigor assessment.

RESUMO Este trabalho propõe uma reflexão sobre a intersecção entre a tradição marxista, em particular o pensamento de György Lukács e seu aporte para a Educação Física, a partir de uma pesquisa exploratória bibliográfica qualitativa e fundamentado pelo método materialismo histórico-dialético, apresentando três eixos investigativos. No primeiro, aponta-se pela elucidação da tradição marxista lukacsiana, no segundo, procura-se contextualizar a Educação Física e seu contato com a teoria marxista a partir do seu processo histórico-político, e no terceiro, desenvolve-se um conjunto de notas a respeito das contribuições do marxismo lukacsiano para a Educação Física.

ABSTRACT: The road system is the main mode used for the transportation of agricultural cargo, and in some cases, it is the only option for handling this type of product. This dependence means that the implementation of tools to support the management of logistical costs can reduce the financial impact with the transport felt by the economic agents operating in the soybean chain. This study contributed to a better understanding of the variables that make up the cost of road freight, generating a system of road freight prediction from a multiple linear regression model using the selection of variables Stepwise, Forward, and Backward elimination. This being said, this research intends to evaluate whether the behavior of soybean road freight is influenced by the variables that make up the productive, economic, and infrastructure dimensions in price formation. The regression models had an explanatory power of 87.20%. In the infrastructure dimension, the most impact variable in soybean road freight was the distance traveled; in the economic dimension, the variables of inflation and fuel price stood out; while in the productive dimension, the main contribution was the volume of production. A more assertive predictability of logistical costs and better understanding of the dynamics of freight price formation helps industry agents in planning and decision-making. Another contribution of this study is that it can be used as a practical tool for predicting soybean road freight on several transportation routes.

The growing demand for food production has led to an increase in agricultural areas, including many with low and irregular rainfall, stressing the importance of studies aimed at mitigating the harmful effects of water stress. From this perspective, the objective of this study was to evaluate calcium pyruvate as an attenuator of water deficit on chlorophyll a fluorescence of five sugarcane genotypes. The experiment was conducted in a plant nursery where three management strategies (E1—full irrigation, E2—water deficit with the application of 30 mM calcium pyruvate, and E3—water deficit without the application of calcium pyruvate) and five sugarcane genotypes (RB863129, RB92579, RB962962, RB021754, and RB041443) were tested, distributed in randomized blocks, in a 3 × 5 factorial design with three replications. There is dissimilarity in the fluorescence parameters and photosynthetic pigments of the RB863129 genotype in relation to those of the RB041443, RB96262, RB021754, and RB92579 genotypes. Foliar application of calcium pyruvate alleviates the effects of water deficit on the fluorescence parameters of chlorophyll a and photosynthetic pigments in sugarcane, without interaction with the genotypes. However, subsequent validation tests will be necessary to test and validate the adoption of this technology under field conditions.

A traça-da-couve (Plutella xylostella) é um inseto que provoca perdas de produção das brássicas. Determinadas populações de P. xylostella expressam resistência à inseticidas resultando no difícil manejo e consequentemente demanda maiores aplicações de agrotóxicos levando à redução de inimigos naturais e poluição ambiental, neste sentido a pesquisa teve como objetivo avaliar a ocorrência de parasitoides de Cotesia plutellae sobre a P. xylostella nas culturas brássicas, para o efeito foi instalado um experimento usando o delineamento de blocos casualizados ma área total de 525 m2. Após análises de variância, constatou-se porcentagens de parasitismo da C. plutellae sobre a P. xylostella de 43.12%, 26.79%, 20.83 e 13.73% para as variedades Tronchuda, Mostarda, KK Cross e Copenhagen Market, no estágio larval 1 a maior densidade média foi registrada quando as larvas tiveram a variedade Tronchuda como hospedeiro com 9.92 larvas/planta, sendo superior às registradas em variedade Mostarda, KK Cross e Copenhagen.

The metallic compound Mn5Si3 hosts a series of antiferromagnetic phases that can be controlled by external stimuli, such as temperature and magnetic field. In this work, we investigate the spin-excitation spectrum of bulk Mn5Si3 by combining inelastic neutron scattering measurements and density functional theory calculations. We study the evolution of the dynamical response under external parameters and demonstrate that the spin dynamics of each phase is robust against any combination of temperature and magnetic field. In particular, the high-energy spin dynamics is very characteristic of the different phases consisting of either spin waves or broad fluctuation patterns.

Cotton is one of the largest agricultural commodities that generate various sources of foreign exchange and employment worldwide. However, water deficiency is an environmental factor that limits the production of this crop, especially in semi-arid regions. We evaluated pyruvate supplementation to mitigate the effects of water stress on colored cotton. Experiments were conducted in a greenhouse. We studied two forms of pyruvate supplementation (SP1- via seed and foliar and SP2- only via foliar); three conditions of irrigation management of the plants: water restriction in the vegetative phase (VE), flowering (FL), and vegetative and flowering (VE/FL); and additional treatment (total irrigation throughout the crop cycle and without pyruvate supplementation). The experimental design included a randomized block in a 2 × 3 + 1 factorial scheme. The factors resulted in seven treatments with three replications, with a total of 21 experimental units. Gas exchange, enzyme activity, and production of components were evaluated. Water restriction in the vegetative phase does not cause losses in BRS Jade cotton when supplemented with pyruvate. However, in the flowering and vegetative phases plus flowering, it reduces gas exchange and production components and increases the activity of antioxidant enzymes in relation to plants under full irrigation. Supplementation with pyruvate via seed plus foliar (SP1) was better for BRS Jade cotton grown under water restriction.