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Abstract: The introduction of chiral organic spacers in low‐dimensional metal‐halide perovskites triggers chiroptical activity, which is appealing for spintronic applications. However, a comprehensive understanding of structure formation and the ability to control phase purity in such materials have yet to be developed. Herein, the impact of processing conditions on the phase purity, microstructure, and chiroptical properties of chiral 2D perovskites is explored. The anisotropic emergence of a 1D perovskite inside the 2D matrix and its dependence on the organic cation chirality, solvent, and thermal annealing conditions are shown. By controlling these parameters, the in‐plane conductivity of the films is nearly doubled. Furthermore, it is demonstrated, for the first time, that solvent choice and the spatial configuration of the organic cation can have an impact on the residual lattice strain and the energetic disorder of the system. The fundamentals presented here can help to improve the film deposition methods for low‐dimensional chiral perovskites, offering strategies to control phase purity.

Using in situ photoluminescence measurements during the spin-coating and annealing steps, this study probes the formation of 2D layers on 3D triple cation perovskite films comparing phenylethylammonium and 2-thiophenemethylammonium iodide bulky cations. This study elucidates the formation mechanisms of the surface layers for both cases and reveals two regimes during 2D layer formation: a kinetic-driven and a thermodynamic-driven process. These driving forces result in different compositions of the 2D/3D interface for each treatment, namely, different ratios of pure 2D (n = 1) and quasi-2D (n > 1) structures. This study shows that a higher ratio of quasi-2D phases is more beneficial for device performance, as pure-2D layers may hamper current extraction. Due to a more evenly distributed formation energy profile among 2D and quasi-2D phases, highly concentrated 2-thiophenemethylammonium iodide appears to be more suited for effective surface passivation than its phenylethylammonium analog.

Abstract Seed priming with biostimulant for soybean is a promising practice contributing positively to the physiological quality and vigor of seedlings, but there are little studies regarding protocols of bioinputs, such as Ascophyllum nodosum L. seaweed extract. We aimed to evaluate the effect of doses of A. nodosum macroalgae in seed priming and its impact on germination and seedling vigor of soybean. Seeds were subjected to priming with A. nodosum extract (ANE) at doses of 0, 1, 2, 3, 4, and 5 mL kg seed−1 during 15 min. Priming with ANE did not influence the first count and seed germination. Soybean seedlings from priming with 5 mL kg−1 ANE showed higher growth and shoot and root dry biomass. We observed increase 18% for shoot dry matter with priming of 5 mL kg−1 ANE compared to untreated seeds. The responses were variable for the emergence speed index in function ANE and did not influence the photochemical processes in photosystem II. Seed priming with ANE contributed in higher chlorophyll index. ANE showed a biostimulant effect on soybean seedlings, providing better growth and biomass characteristics, being promising in seed priming, but further studies are suggested in order to increase information regarding its use protocol for soybean.

Este estudo objetivou avaliar as evidências acerca dos fatores de risco para reinfeção de sífilis. Esta é uma revisão integrativa, conduzida pelo protocolo PRISMA, por meio das bases de dados: Literatura Latino Americana e do Caribe em Ciências da Saúde (LILACS) via Biblioteca Virtual em Saúde (BVS), US National Library of Medicine/National Institutes of Health (PubMed/MEDLINE), Web of Science, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL) e EMBASE, onde foram rigorosamente selecionados treze artigos. Os principais fatores associados a reinfecção por sífilis foram coinfecção pelo Vírus da Imunodeficiência Humana (HIV) e Homens que fazem Sexo com Homens (HSH). Outros fatores, também foram indicados, porém, em menor frequência, como sífilis latente (assintomática), idade entre 20 a 40 anos, múltiplos parceiros sexuais, entre outros. Considerando o papel crucial de populações específicas como fatores fortemente associados aos casos de reinfecção por sífilis, são necessárias ações de educação em saúde de qualidade nas instituições de saúde, por profissionais de saúde qualificados. Esta revisão identifica dados decisivos para elaboração de estratégias públicas em torno da temática. Os resultados elucidam a indispensável busca por estratégias eficazes de prevenção da reinfecção de sífilis por parte das autoridades de saúde pública.

ABSTRACT Using organic residues and bioinputs is a promising and sustainable practice to produce seedlings with forest essences, such as Cedrela fissilis Vell. (cedar), a vulnerable species close to extinction due to intensive exploitation in native areas. Thus, we aimed to evaluate the effect of different substrates based on organic residues associated with or without the application of Parachlorella sp. microalgae in the emergence and morphophysiology of C. fissilis seedlings. Sowing was carried out on six substrates: Oxisol with a clayey texture; Oxisol + Parachlorella sp.; Oxisol with sheep manure (3:1, v v–1); Oxisol with sheep manure + Parachlorella sp.; Oxisol with cattle manure (3:1, v v–1); and Oxisol with cattle manure + Parachlorella sp. The addition of organic residues to the soil, especially cattle manure, contributes to increasing the percentage of emergence, plant height, chlorophyll index, CO2 assimilation rate, and instantaneous carboxylation efficiency of Rubisco due to the superior chemical attributes in the substrate, which promote greater physiological efficiency. Organic residues increased the water use efficiency of seedlings. The application of Parachlorella sp. microalgae contributes to increases in the CO2 assimilation rate and stomatal conductance when seedlings are grown only in Oxisol. C. fissilis seedlings produced in the substrate with sheep and cattle manure showed better growth and gas exchange characteristics.

ABSTRACT Light stress damages the photochemical apparatus and affects seedling growth of forest species. Using potassium silicate (K2SiO3) can mitigate these deleterious effects and contribute to the acclimatization and robustness of seedlings. This study evaluated the effect of K2SiO3 and shading levels on the photochemical and growth of Alibertia edulis (Rich) A. Rich seedlings. The experiment was arranged under three light conditions based on shading levels of 0 % (full sun), 30 %, and 70 %. Four doses of K2SiO3 applied through foliar spray were tested: 0.0, 2.5, 5.0, and 10.0 mL L–1. Cultivation under full sun and under 70 % of shade was stressful for A. edulis, while cultivation under 30 % of shade improved plant growth. Increasing application of K2SiO3 in seedlings under full sun damaged the reaction center, causing lower photochemical yields, but increased the photochemical efficiency of photosystem II under 30 % of shade. Using K2SiO3 contributed to leaf water regulation while applying 10.0 mL L–1 increased chlorophyll indices, leaf area, physiological indices, and the quality of seedlings cultivated under full sun and 30 % of shade. Using 10.0 mL L–1 K2SiO3 mitigated the negative effects of light stress under full sun. It provided high photochemical efficiency, morphology aspects, and Dickson quality index A. edulis seedlings in environments with high or moderate light availability.

RESUMO Esse trabalho descreve o efeito dos extratos aquosos de algumas leguminosas arbóreas brasileiras sobre a germinação e o desenvolvimento radicial de alface (Lactuca sativa L. cv. “Grand Rapids”). Os extratos foram obtidos por maceração estática das folhas com água destilada e os testes de germinação foram efetuados com os extratos aquosos ou destes isentos de fenólicos pela filtração em polivinilpirrolidona (PVP). A maioria das espécies testadas inibiu o desenvolvimento radicial de alface, mas apenas Mimosa artemisiana afetou sua germinação. A filtragem em PVP anulou apenas o efeito de M. artemisiana sobre a germinação, sugerindo neste caso, a natureza fenólica das toxinas envolvidas.

Por meio da antropologia da saúde, podemos compreender o terreiro de umbanda como parte de um sistema popular de cuidado. Este estudo teve por objetivo investigar as concepções de saúde e doença produzidas por zeladores de terreiro de umbanda. Participaram dez zeladores de terreiro da cidade de Uberaba (MG/Brasil), sendo três mulheres e sete homens, com idades entre 40 e 76 anos. O tempo médio de atuação como dirigente foi de 18,4 anos, variando de cinco a 43 anos. Os terreiros chefiados por esses participantes atendem entre 15 e 280 pessoas por dia de funcionamento. Pela análise das entrevistas, destaca-se que o cuidado em saúde oferecido pelos zeladores ultrapassa os limites rituais, nas cerimônias públicas, sendo prestado de modo contínuo nos terreiros. As posturas assumidas pelos entrevistados envolvem ações de escuta, acolhimento e proximidade física no momento da urgência. Pelas narrativas, pode-se concluir que o zelar, no sentido de gerenciar o espaço do terreiro, espiritual e materialmente, não pode ser dissociado do cuidar, significando os zeladores como importantes agentes populares de saúde.

Abstract Transgenic Bt soybean plants have been developed to control insect pests, such as Anticarsia gemmatalis and Chrysodeixis includens. This objective has been achieved successfully; however, recently, some authors claimed that Bt soybean plants have been more susceptible than non-Bt soybean to Bemisia tabaci MEAM1. In addition, it is unknown whether Bt soybean plants infested by B. tabaci become less resistant to target pests. Therefore, this study aimed to evaluate: (i) whether the previous infestation with B. tabaci can compromise Bt and non-Bt soybean resistance to C. includens; (ii) the effects of B. tabaci infestations on Bt and non-Bt soybean plant growth; and (iii) whether B. tabaci feeding reduces contents of chlorophyll and carotenoids of soybean plants. Bt and non-Bt soybean plants pre-infested with B. tabaci showed no changes in resistance to C. includens. Bt soybean plants infested with B. tabaci showed a lower plant height than uninfested plants. Differently, non-Bt soybean plants exhibited no reduction in plant growth due to B. tabaci feeding. Bt soybean plants suffered a reduction in dry matter only under double infestation (B. tabaci and C. includens), while non-Bt soybean plants experienced reduction in dry matter when infested with B. tabaci and C. includens or by C. includens only. B. tabaci feeding did not alter contents of chlorophyll and carotenoids, and perhaps the reduction in plant growth was related to salivary toxins. Concluding, both Bt and non-Bt soybean plants were susceptible to B. tabaci feeding, evidencing necessity of developing soybean cultivars resistant to B. tabaci.

Abstract Light and water availability can impact plant survival and growth, making ecophysiological studies crucial for understanding their tolerance and to single and combined stresses. The aimed of this study was to investigate the physiological and growth responses of Inga vera Willd. plants induced by different water regimes and light intensities. Three water regimes were implemented based on substrate water retention capacity (WRC) - 50%, 75%, and 100%, along with shading levels (SH) - 0% (full sun), 30%, and 70%. Evaluations were conducted at 25 and 50 days after applying the water regimes, and during a recovery period of 30 days when all treatments were maintained at 75% of WRC. Photochemical efficiency, gas exchange, chlorophylls indices, growth, quality of the seedlings and content proline amino acid were assessed. Overall, I. vera plants showed greater sensitivity to increased exposure to light than to low water availability. The interaction of SH + WRC was beneficial for the gas exchange and chlorophylls indices characteristics under SH 70% + WRC 75-100% at 25 and 50 days, with higher results, greater plant growth and higher proline contents for leaves and roots under SH 30% and 70% + WRC 50%, 75% and 100% at 25 and 50 days. There was no recovery effect for seedlings grown in full sun. The plants grown under shade during the recovery period maintained their values for most of the characteristics evaluated. SH 30% + WRC 75% contributed to an increase in photosynthetic metabolism and, as a result, to the quality of the seedlings.

Este trabalho propõe uma análise do efeito de fatores sociais no desempenho escolar aferido pelo Sistema Nacional de Avaliação da Educação Básica (Saeb) entre 2013 e 2019. O objetivo é discutir o impacto da origem social nas trajetórias individuais, aqui abordadas através dos dados secundários fornecidos pelo Instituto de Estudos e Pesquisas Educacionais Anísio Teixeira (Inep). Serão discutidas, principalmente, duas perspectivas consolidadas na literatura sobre desigualdades educacionais: uma em relação à conservação e reprodução de posições de origem, o tipo “Escola Reprodutora” e outra em relação aos casos de Escolas que conseguem controlar desigualdades de origem e oferecer condições adequadas ao desenvolvimento dos estudantes, o tipo “Escola Eficaz”. Entre esses dois extremos, que se configuram em categorias analíticas/tipos ideais, contribuímos com um panorama do efeito de fatores sociais ao longo do tempo. Com isso sistematizamos evidências empíricas em relação às desigualdades de resultados escolares e padrões de estratificação educacional.

Justificativa e Objetivos: apesar da importância dos acompanhantes/visitantes para pacientes hospitalizados em precauções específicas, nota-se que os riscos de exposição e disseminação de microrganismos nos serviços de saúde por essa população ainda são incipientes na literatura. Dessa forma, objetivou-se caracterizar as recomendações vigentes sobre precauções específicas para acompanhantes e visitantes de pacientes hospitalizados e analisar as barreiras para a sua implementação sob a ótica de prevencionistas de infecção. Métodos: estudo descritivo e exploratório, de abordagem quantitativa, com 89 prevencionistas de infecção, entre março e junho de 2020. Dados coletados por questionário eletrônico, com amostragem tipo “bola de neve” e analisados segundo frequência das respostas. Resultados: a higienização das mãos foi a recomendação mais indicada (>95,0%). Quanto às não conformidades, destacou-se permanecer no quarto sem paramentação (78,6%), frequentar outros quartos (53,9%) e manter portas abertas em precaução para aerossóis (51,7%). Referente às estratégias adotadas para a orientar os acompanhantes/visitantes, houve predomínio da orientação verbal individual (92,4%). A principal barreira citada foi a falta de política institucional (56,2%). Conclusão: não houve uniformidade nas recomendações, e não conformidades e barreiras foram elencadas. Destaca-se a importância de diretrizes de prevenção específicas para esse público e estratégias educativas efetivas para sua implementação.

Information on tolerance to isolated or combined abiotic stresses is still scarce for tree species, although such stresses are normal in nature. The interactive effect of light availability and water stress has been reported for some native tree species in Brazil but has not been widely investigated. To test the hypothesis that shading can mitigate the stressful effect of water deficit on the photosynthetic and antioxidant metabolism and on the growth of young Hymenaea courbaril L. plants, we evaluated the following two water regimes: a) continuous irrigation – control (I) - 75% field capacity. and b) water deficit (S), characterized by irrigation suspension associated the two following periods of evaluation: P0 - when the photosynthetic rate of plants subjected to irrigation suspension reached values ​​close to zero, with the seedlings being re-irrigated at that moment, and REC - when the photosynthetic rate of the re-irrigated plants of each shading levels reached values ​​similar to those of plants in the control treatment, totaling four treatments: IP0, SP0, IREC, and SREC. The plants of these four treatments were cultivated under the four following shading levels: 0, 30, 50, and 70%, constituting 16 treatments. Intermediate shading of 30 and 50% mitigates the water deficit and accelerates the recovery of H. courbaril. Water deficit associated with cultivation without shading (0%) should not be adopted in the cultivation or transplantation of H. courbaril. After the resumption of irrigation in the REC, the other characteristics presented a recovery under all cultivation conditions. Key message: Intermediate shading of 30 and 50% mitigates the water deficit and accelerates the recovery of H. courbaril.

ABSTRACT This research aimed to investigate the occurrence of Chlamydia sp., Morbillivirus sp., Parvovirus sp., Leishmania sp. and Alphacoronavirus sp. in captive giant anteaters. Blood and fecal samples were taken from 16 animals in institutions from the states of Minas Gerais, Bahia and Distrito Federal, which had been in captivity for at least a year. A commercial rapid chromatographic immunoassay test was used for detecting coronavirus and parvovirus antigens, in addition to antibodies against leishmaniasis, all results being negative. In the case of the test for antibodies against distemper, four (4/16; 25%) anteaters had an average titration, two (2/16; 12.5%) a low titration and ten (10/16; 62.5%) were non-reactive. Using the DOT-ELISA (dot blotting) method for detection of immunoglobulin G, only one specimen obtained a 1 : 40 titration. For the polymerase chain reaction tests for Leishmania and Chlamydia, all samples were negative.

The total demand for and uptake of nutrients by vegetation is rarely quantified or compared across vegetation types. Here, we describe different nutrient use and allocation strategies in neotropical savanna (cerrado) and transitional forest (cerradão) tree communities composed of different species, report leaf nutrient resorption and calculate ecosystem-level nutrient use efficiency. We couple net primary productivity (NPP) estimates with nutrient stoichiometry to quantify nutrient demand and nutrient flows at the whole-stand scale for different components of vegetation biomass. Species from the two vegetation communities showed similar mean nutrient concentrations and nutrient resorption efficiency, except for wood P concentration that was fourfold higher in cerrado than cerradão species. The cerradão showed higher canopy NPP, while fine roots and wood NPP were similar for the two vegetation types. Nutrient requirement in the two vegetation types was dominated by the demands of the canopy, with canopy resorption generally contributing more than 50 % of the total canopy demand for nutrients, while less than 35 % of N, P, K, Ca and Mg were allocated to wood or fine roots. Proportionally, cerrado showed higher nutrient demand from fine roots (over 35 % of the total nutrient demand) and for the wood component (over 13 % of the total nutrient demand), while ∼ 60 %–70 % of the cerradão nutrient demand was allocated to the canopy. The proportional difference in nutrient allocation to the different biomass components suggests cerrado species allocate less nutrients to a given fine root biomass, but more nutrients to a given wood biomass. Our findings suggest that cerradão species are more limited in P and K than cerrado species, inducing higher resorption to compensate for low uptake. Moreover, we found that N uptake for cerradão was higher with lower N use efficiency, i.e. the amount of production per nutrient unit, leading higher N demand compared to the cerrado. This difference in nutrient dynamics explains how similar soils and the same climate dominated by savanna vegetation can also support forest-like formations. Tree species composition is likely the major factor regulating nutrient use, limiting vegetation transitions and influencing nutrient demand at landscape scales.

Abstract Information from Pereskia aculeata Miller (Cactaceae) responses regarding the portion of the stem cuttings branch parental plants and the shading level need to be investigated in order to establish techniques for their producing seedlings. We aimed was to evaluate the effect of cutting types and shading levels in the production of P. aculeata seedlings. We studied three cutting types, collected from different portions of the stem cuttings branch: herbaceous, semi-hardwood, and hardwood, which were arranged under two shading levels: 0% (full sun) or 50% (shade). The selected parent plants had an adequate and vigorous phytosanitary aspect. After 90 days after the cuttings, the seedlings were evaluated regarding survival, growth indicators, biomass production and partitioning, and allometric indices. Seedlings from hardwood cuttings and produced under 0% shading showed higher survival. The largest number of sprouts occurred in seedlings of semi-hardwood and hardwood cuttings. The highest leaf area values occurred in seedlings of semi-hardwood and hardwood cuttings under 0% shading. Seedlings from hardwood cuttings had higher biomass allocation in the roots under 50% shading. Seedlings of herbaceous and semi-hardwood portion allocated values ≥ 70% of the biomass in the aerial part. Seedlings of species are able to adjust to different shading levels as a plasticity mechanism. For the production of P. aculeata seedlings, the hardwood portion of the stem cuttings branch under full sun cultivation is recommended. In addition, semi-hardwood cuttings grown under 50% shading can also be used for seedlings production.

Abstract Flooding can damage the photosynthetic apparatus and initial growth of Schinus terebinthifolia. We aimed this study evaluates the potential of silicon (Si) and salicylic acid (SA) as mitigating agents on the ecophysiological responses and initial growth of S. terebinthifolia subjected to flooding periods. Seedlings were grown under the following conditions: 1) control (non-flooded): daily irrigation, 2) Flooded (F): storage of seedlings in a 500 L plastic pool, keeping the water depth at ± 2.0 cm above the substrate level, 3) F + 1.0 mM Si, 4) F + 2.0 mM Si, 5) F + 1.5 mM SA, and 6) F + 3.0 mM SA, and evaluated to 15 and 30 days. We observed that flooded seedlings formed hypertrophied lenticels on the stem on the 7th day as a stress adjustment strategy. S. terebinthifolia is sensitive to flooding, although it maintains a stable gas exchange for up to 15 days in this condition. The applications of 1.0 mM Si mitigated the pronounced decrease of gas exchange by 30 days. Using 1.0 mM Si and 3.0 mM SA contributed for integrity of the photosynthetic apparatus and to photochemical activities in the reaction centers, in addition favors to higher seedling biomass and quality under flooding. Foliar application of Si and SA is promising practice for photosynthetic metabolic and initial growth of S. terebinthifolia seedlings under flooded stress.

O xilitol é um edulcorante encontrado em uma ampla gama de alimentos industrializados para seres humanos. No entanto, seu consumo por cães repercute em importantes alterações metabólicas e fisiopatológicas. Neste contexto, este trabalho teve como objetivo avaliar o conhecimento de tutores a respeito do xilitol, de sua presença em diferentes produtos alimentícios destinados à seres humanos e dos riscos à cães. Foi desenvolvido um questionário, aplicado a tutores de cães de forma online no período de 06 a 12 de outubro de 2021, onde se obteve 84 respostas. Os dados foram analisados através de distribuição de frequências. Pôde-se observar que 42,9% dos tutores conhecem ou já ouviram falar do xilitol relacionando-o a um adoçante; dentre os que conhecem a substância apenas 41,7% dos respondentes relataram reconhecer alimentos que possuem xilitol em sua composição, no entanto, os relatos destes tutores apresentaram baixa relevância; 63,9% dos tutores que declararam conhecer a substância relacionaram-na a toxicidade em cães. Conclui-se que a maior parte dos tutores desconhecem o xilitol e os produtos, com o edulcorante, que apresentam risco para cães. Com isso, faz-se necessárias campanhas educativas, bem como, reforçar a comunicação entre médicos-veterinários e tutores, durante os atendimentos, acerca de substâncias tóxicas para cães.

As vivências psicossociais de estudantes cotistas são temáticas de interesse da psicologia no campo de estudos das ações afirmativas. Esta pesquisa objetivou descrever as trajetórias de estudantes cotistas para o ingresso em uma universidade pública federal. Participaram 11 universitários cotistas, estudantes de psicologia, subdivididos em dois grupos focais. Utilizou-se da análise do discurso, de orientação inglesa, como estratégia interpretativa. As narrativas foram organizadas em seis repertórios: a cultura familiar sobre o ensino superior; as limitações e a precariedade da educação básica pública; a busca por complementação educacional; a rotina e as dificuldades anteriores ao ingresso na universidade pública; as atividades extracurriculares e os institutos federais para viabilizar o acesso ao ensino superior público. A análise das trajetórias dos cotistas evidenciou vivências psicossociais comuns aos estudantes. Os sentidos compartilhados sinalizaram que para alcançarem o objetivo de ingressar em uma universidade pública federal foi preciso, além do esforço pessoal intenso, disciplina e novos hábitos, romper com valores culturais e familiares, contar com apoio de instituições de ensino de qualidade referendada como, por exemplo, os institutos federais ou recorrer à complementação de estudos. Espera-se que este estudo contribua para a elaboração de intervenções psicossociais aos cotistas nos âmbitos da orientação acadêmica e de carreira e também para a consolidação das referidas políticas de ações afirmativas.

The sloshing phenomenon occurs in partially filled tankers due to sudden movement can affect the tank structure integrity and impair the dynamic stability of the tanker. The effects of sloshing phenomena in a spray mixture tank due to acceleration or deceleration of the agricultural vehicle is investigated under three filling levels of 25%, 50%, and 75%. The pressure time distributions on the tank wall were evaluated by using a multiphase transient model (water and air as an ideal gas) and a free surface flow in a homogeneous model. It was possible to verify the wave behavior of sloshing. The condition of 75% tank filling volume generated the highest pressure on the tank wall. The effectiveness of two types of vertical baffles in suppressing pressure was numerically investigated. Shear stress on the tank bottom wall under these proposed arrangements was analyzed by steady-state models and mechanical agitation, considering a filled tank. The proposed solution based on two partial vertical baffles and a central gap was the most effective. It promotes the higher reduction of wall impact pressure and other sloshing instabilities and maintains similar results of mixture agitation of the tank without baffles.

Water deficit is one of the factors that most influence plant growth and yield. Thus, this study aimed to evaluate the effect of silicon and salicylic acid application and water deficit on the growth and photosynthetic and osmoregulatory metabolism of Talisia esculenta Radlk. seedlings and their recovery potential after the resumption of irrigation. Six treatments were performed: irrigation, irrigation suspension, irrigation suspension + silicon at 0.5 g L−1, irrigation suspension + silicon at 1.0 g L−1, irrigation suspension + salicylic acid at 50 mg L−1, and irrigation suspension + salicylic acid at 100 mg L−1. The evaluations were carried out at the beginning of the experiment, at 10 and 15 days after irrigation suspension, when the seedlings showed a photosynthetic rate close to zero, and at recovery. The plants were subjected to water restriction for up to 15 days, then re-irrigated until the recovery point, which was monitored based on the photosynthetic rate. Silicon application attenuated the harmful effects of water deficit on gas exchange and initial fluorescence, promoted proline accumulation in the leaf and root, and provided higher seedling quality. Salicylic acid application contributed to the maintenance of the relative water content of leaves during the water deficit period. Silicon and salicylic acid applications can attenuate the harmful effects of water stress, with silicon being the most effective agent in maintaining its growth and metabolism.

Abstract This study aimed to evaluate the potential of shading in reducing the stressful effect of water restriction on photosynthetic and antioxidant metabolism, favoring the growth of Ormosia arborea seedlings and the recovery metabolic. The shadings levels studied were: 0, 30 and 70%. Two water regimes were implemented: control, in which the plants were irrigated at 75% of soil water retention capacity and water restriction, in which the irrigation was suspended until the photosynthetic rate reached values close to zero (P0), period at which the seedlings were re-irrigated. There were two evaluation periods: P0 and recovery. We observed that water restriction reduced photosynthetic metabolism, growth and quality of O. arborea seedlings by increasing the activity of antioxidant enzymes. The seedlings present higher quality index, stomatal conductance, intrinsic carboxylation efficiency and transpiration when cultivated under 70% shading in recovery. The stressful effect of water restriction was mitigated by the shading of 70%, where the seedlings were able to recover, resuming their photosynthetic metabolism and quality after resumption of irrigation. In addition, 0% shading is not indicated for this species.

Habitat selection has long been a central theme in ecology and has historically considered both physiological responses and ecological factors affecting species establishment. Investigating habitat selection patterns at different scales can provide important information on the relative roles of the environmental factors influencing the organisms’ abilities to use their surrounding habitat. This work aimed at investigating which environmental factors determine habitat selection by Rhinella icterica tadpoles, and also took the opportunity to investigate how the scale in which tadpoles and environmental data are sampled might influence the habitat selection results. A total of 2.240 tadpoles were counted in the whole sampling area, and while substrate cover and depth were the variables that better explained the abundance of tadpoles at the larger scale (plot level), depth and water turbidity better explained tadpoles’ abundance at the smaller scale (subplot level). The results suggest that avoiding predation by matching the background color is a likely process explaining tadpoles’ occupancy at both scales. Depth is known to influence tadpole habitat use in the tropics, and although its combination with turbidity and substrate cover varied between scales, our study suggests that sampling at different scales might not affect the inferred ecological processes driving habitat selection. This information might also be useful to predict tadpoles’ responses to micro-environmental perturbations and help in guiding the choice of parameters that should be taken into account when analyzing the effects of habitat degradation in Atlantic Forest amphibian populations.

Abstract Silicon (Si) is a beneficial element that can mitigate effects of water stress on photosynthetic metabolism and plant growth. Thus, the aimed was to evaluate the effect of Si in mitigating the stressful effect of water deficit and flooding in Eugenia myrcianthes Nied. seedlings. The seedlings received three silicon doses (0, 2, and 4 mmol) and were subjected to two water regimes (I – continuous irrigation and S – water fluctuation, characterized as water stress obtained by two cycles of water regimes: irrigation suspension and flooding). Each cycle was ended when the seedlings had a photosynthetic rate close to zero (P0) when the stressful irrigation condition was normalized until the photosynthetic rate reached the values of the control seedlings (REC). The evaluations were carried out in five periods: T0 – initial seedling condition; 1st and 2nd P0; and 1st and 2nd REC. The E. myrcianthes seedlings reached P0 at 22 and 50 days under water deficit and flooding, respectively. Water stress caused damage to photochemical activities in photosystem II. E. myrcianthes is a species sensitive to water stress, but capable of adjusting to water fluctuation, and the application of 2 mmol Si contributed to the regulation of gas exchange, photochemical yields, and growth of this species at the deficit and flooding phases. We emphasize that E. myrcianthes seedlings have potential for resilience due to physiological plasticity, regardless of the silicon application.

Abstract Water deficit to causes serious problems in the growth and development of plants, impairing their metabolism. Thus, it is necessary to use agents that can mitigate plant damage. This study assesses the potential of silicon to mitigate water deficit stress in Dipteryx alata Vogel seedlings and to help in their recovery after the resumption of irrigation. The study analyzed four water regimes: (I) Continuous irrigation; (II) Water deficit without Si; (III) Water deficit + 0.75 mL Si; and (IV) Water deficit + 1.50 mL Si. Seedlings were evaluated in four periods: (1) (T0 – time zero) at the beginning of the experiment, before irrigation suspension; (2) (P0) when the photosynthetic rates (A) of seedlings under irrigation suspension reached values close to zero, period in which irrigation was resumed; (3) (REC) when A reached values close to those of seedlings under continuous irrigation, characterizing the recovery period; and (4) (END) 45 days after REC, when seedlings were kept under continuous irrigation, similar to the control. Application of 0.75 mL Si alleviates damage to the photosynthetic apparatus of D. alata seedlings that remain longer under water deficit, and contributes to faster physiological recovery after the resumption of irrigation. D. alata seedlings have recovery potential after the stress period, regardless of Si application.

ABSTRACT Water availability is one of the most important factors for the growth of tree seedlings in forestry-related regions. We hypothesized that under different water regimes, a water-retaining polymer (hydrogel) can positively contribute to chlorophyll- a fluorescence and growth in Campomanesia xanthocarpa (Mart.) O. Berg. Four water retention capacities (WRC) were evaluated: 25%, 50%, 75%, and 100%, depending on the presence or absence of hydrogel at the substrate. The lowest WRCs, particularly those under 25% without hydrogel, reduced chlorophyll index and negatively affected the photochemical activities of photosystem II. However, under low water availability the hydrogel mitigated the damage inflicted on the reaction centers and chlorophyll synthesis. The greatest growth effects occurred at 100% WRC in the presence of the hydrogel. Physiological indices were higher under 100% WRC without hydrogel and 50% with hydrogel. The increase in biomass and Dickson quality were more pronounced in the seedlings produced under 50% WRC and hydrogel, and the addition of these parameters to the substrate contributed to more viable morphophysiological indicators for the production of C. xanthocarpa seedlings.

Abstract This study aimed to evaluate the effect of exogenous application of salicylic acid on the photosynthetic metabolism and quality of Eugenia myrcianthes seedlings under water deficit and their recovery potential after rehydration. Two water regimes were evaluated, as follows: control - plants irrigated daily (I) and water deficit (S), with and without the application of 400 mg L–1 of salicylic acid (SA), totaling four treatments. Seedlings were evaluated at three times: at the beginning of the experiment (T0), that is, when the irrigation was interrupted; when the photosynthetic rate reached values close to zero (P0 - 15 days after irrigation interruption), that is, when irrigation restarted; and when the photosynthetic rate was recovered (REC). Eugenia myrcianthes seedlings were negatively affected when subjected to water restriction; salicylic acid attenuated the damage to the photosynthetic apparatus by acting positively on the relative water content in the leaves, SPAD index, photosynthetic metabolism, superoxide dismutase and peroxidase enzyme activity, and seedling growth in P0. Eugenia myrchiantes presented potential for recovery after resumption irrigation. The application of SA contributed to the maintenance of gas exchanges, photochemical processes and quality of E. myrcianthes seedlings during and after water deficit, suggesting the promotion of plant resistance induction.

Abstract During the first 15 years of the twenty-first century, Brazil’s economic growth and public policies were in the center of the debate on the growing “new middle class.” This new middle class is defined by people’s household income between the upper 10th percentile and the median (Neri, A Nova Classe Média, 2008). Although there has been a consensus about the increase in consumption and the improvement of living conditions for a significant proportion of the population, there is less agreement about the decline in inequality and the change in class distribution. Previous work was directed at challenging the very idea that Brazil had become a middle-class country during the first decade of this century, basically weighting class distribution against income distribution. In this article, we aim to step into the income distribution debate using six income groups as proportions of the median household per-capita income. Our data source is the National Household Sample Survey (PNAD-IBGE/Brazil) in 2001, 2008, and 2015. We analyze groups’ income distribution and characteristics using multinomial logistic models to take into account the effects of socioeconomic variables. We argue that there is significant stability in groups’ income structure during the period, revealing their resistance to inequalities (similar to the findings in the works of Piketty and Souza). We also indicate that the odds of being included in the upper-income categories are quite unequal, considering socioeconomic variables. Finally, we point out that the gains observed from 2001 to 2008 had faded by 2015 when the odds of being included in the upper-income categories were remarkably similar to those of 2001.

ABSTRACT The use of water-retaining polymer (hydrogel) can mitigate the damage to the photosynthetic apparatus and increase the robustness of young plants under water deficit conditions. Thus, the aim of this study was to evaluate the effect of water-retaining polymer on the morphophysiological aspects of Schinus terebinthifolia Raddi submitted to water deficit. The studied water regimes were characterized by three plant irrigation management: 1) control: irrigated daily, 2) stress: water deficit (irrigation suspension) and 3) stress + hydrogel: water deficit + water-retaining polymer. The plants were submitted to irrigation suspension until photosynthesis approached zero [1st P0], followed by resumption of irrigation (REI) for 15 days. After REI, until recovery of photosynthetic rate of plants, the maintenance of irrigation of all plants for 90 days, characterizing the final recovery (125th day of experiment). The photosynthetic rate reached values close to zero in plants under stress on the 20th day of water restriction, whereas the plants in conditions with hydrogel did not show a decrease in leaf metabolism. Excluding intercellular CO2 concentration, physiological parameters were lower on 1st P0 in plants under water deficit grown without hydrogel than those in plants grown with hydrogel, but all plants showed physiological plasticity. The use hydrogel contributed to the maintenance of the photosynthetic capacity of S. terebinthifolia under water deficit.

Polycystic kidney disease (PKD), also known as autosomal dominant polycystic kidney disease (ADPKD) is a genetically heterogeneous condition characterized by cysts in renal parenchyma. It is the most prevalent inherited disease of domestic cats. MicroRNAs (miRNAs or ncRNA) are short, noncoding, single-stranded RNAs that may induce PKD cytogenesis by affecting numerous targets genes as well as by directly regulating PKD gene expression. We compared the relative expression profile of miR-20a, -192, -365, -15b-5p, and -16-5p from plasma and serum samples of nine domestic cats with PKD1 mutation, detected by polymerase chain reaction (PCR), and a control group (n = 10). Blood samples from cats with PKD1 mutation provide similar concentrations of microRNAs either from plasma or serum. Serum miR-20a is upregulated in PKD group with p < 0.005; Roc curve analysis showed an AUC of 90,1% with a cut-off value sensitivity of 77.8% and specificity of 100%. This data provides important information regarding renal miRNA expression in peripheral blood sampling.

Durante a crise decorrente da pandemia, as desigualdades se exacerbaram e as disparidades entre nações, internas e externas, aumentaram. A crise socioeconômica vivida no Brasil não é exceção. Os impactos de longo prazo, ocioeconômicos e políticos, e como eles moldam a produção e a reprodução das desigualdades continuarão a dominar os debates sociológicos contemporâneos. Propomos um conjunto de artigos originais que se concentram não apenas na mensuração das desigualdades sociais, mas buscam articular os complexos processos sociais a partir de novas evidências empíricas sobre distribuição de riqueza, bem-estar e chances de vida no século 21. Apesar de ser um país de industrialização tardia, as tendências gerais observadas no Brasil podem lançar luzes sobre processos similares em outras sociedades e este dossiê visa fornecer uma análise aprofundada das desigualdades persistentes e profundas em diferentes contextos

Absolute growth rates change with tree size and age, shifting throughout species ontogeny. The study on interspecific variation in plant traits has generated important insights into the life-history strategies and their consequences for ecosystem functioning. However, it remains unknown to what extent – and even if – species’ functional traits are related to the variation in their growth trajectories. We set out to model growth trajectories of 45 woody species from the Brazilian Atlantic Forest in a secondary subtropical forest under regeneration, aiming to understand if species can be grouped by their growth patterns throughout ontogeny and if these groups could be classified in distinct ecological strategies based on key plant traits. We used a maximum likelihood estimation approach to predict growth trajectories using three ecologically relevant parameters [maximum growth rate (Gmax), diameter at maximum growth rate (Dopt), and the ontogenetic variability in growth rate (K)] followed by multivariate analyses to detect associations among phylogenetic relationships, plant traits, and growth parameters and classify species into growth pattern groups. Across species, growth trajectory parameters varied widely. The cluster analysis identified three distinct groups based on growth trajectories parameters, which were not functionally or ecologically well defined. Our findings supports the idea that traits describing plant size and tree shape, such as maximum height, canopy volume and height to diameter ratio, were generally the best predictors of species growth parameters throughout ontogeny, even though traits representing resource-use and reproductive strategies also played a significant role. Growth-trait framework can be understood as a continuum of multi-trait combinations where, at one end of the gradient, we find trees with higher growth rate and larger diameters supporting a voluminous canopy combined with lower investment in leaf tissue and smaller diaspore; at the other end, taller trees supporting a smaller canopy with higher investment in leaf tissue and longer diaspore. Ultimately, we have shown that tree architecture, leaf and reproductive traits significantly influence growth trajectory along tree ontogeny, which may be the reason why objectively grouping species based on growth-trajectories parameters is ineffective, at least in highly diverse secondary subtropical forests undergoing regeneration.

Abstract The aim of this research was to evaluate the effect of abscisic acid (ABA) on gas exchange and the activity of antioxidant enzymes of Ormosia arborea (Vell.) Harms seedlings under water deficit and its influence on the recovery potential of the seedlings. The experiment was conducted using four treatments, being daily irrigation or water restriction without and with 10 μM ABA. Seedlings under water deficit + ABA showed greater adjustment to drought, and when re-irrigated, they restored photosynthetic metabolism and water potential. ABA minimizes the reduction in the photosynthetic metabolism and water potential of the leaf, however, it does not increase the antioxidant activity of the O. arborea seedlings under water deficit. These results suggest that this species exhibits plasticity, which enables it to survive also in environments subjected to temporary water deficit regardless of the supplementation of ABA. We suggest that other doses of ABA be researched to expand the beneficial effect of ABA on this species.