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O objetivo do presente estudo foi analisar o impacto da pandemia de COVID-19 nas notificações de arboviroses, comparando valores obtidos nos boletins epidemiológicos do ano de 2019 a 2022. Constatando assim, um grande número de possíveis doenças não notificadas destes agravos durante o período pandêmico. Trata-se de um estudo descritivo, com o intuito de estabelecer uma relação entre os números obtidos metodologicamente através de pesquisas de artigos SCIELO, periódicos, boletins epidemiológicos e dados do DATASUS e quantidade de subnotificações identicamente relatadas no período de estudo. Os resultados obtidos mostraram uma semelhança entre os dados analisados nos anos de 2019 e 2022, no entanto houve uma relevante descontinuidade entre os intervalos de 2020 e 2021. Conclui-se que tal fato constatado trata-se de subnotificações de casos durante o período de maior incidência do vírus SARS-CoV-2, influenciadas pelas alterações que a pandemia trouxe à tona nos âmbitos da sociedade, política, economia e principalmente toda a área da saúde, pois durante o período pandêmico, identificou-se que a atenção principal da saúde brasileira estava voltada para a resolução ou diminuição dos danos causados por um novo vírus e negligenciando ações de promoção e prevenção à saúde de doenças endêmicas do nosso território, como a dengue.

IL-7 and IL-7R are essential for T lymphocyte differentiation by driving proliferation and survival of specific developmental stages. Although early T lineage progenitors (ETPs), the most immature thymocyte population known, have a history of IL-7R expression, it is unclear whether IL-7R is required at this stage. In this study, we show that mice lacking IL-7 or IL-7R have a marked loss of ETPs that results mostly from a cell-autonomous defect in proliferation and survival, although no changes were detected in Bcl2 protein levels. Furthermore, a fraction of ETPs responded to IL-7 stimulation ex vivo by phosphorylating Stat5, and IL-7R was enriched in the most immature Flt3+Ccr9+ ETPs. Consistently, IL-7 promoted the expansion of Flt3+ but not Flt3− ETPs on OP9-DLL4 cocultures, without affecting differentiation at either stage. Taken together, our data show that IL-7/IL-7R is necessary following thymus seeding by promoting proliferation and survival of the most immature thymocytes.

The objective of the present study was to analyze the impact of the COVID-19 pandemic on arbovirus notifications, comparing values obtained in epidemiological bulletins from 2019 to 2022. Thus, noting a large number of possible unreported diseases of these diseases during the pandemic period. This is a quantitative study, intending to establish a relationship between the numbers obtained methodologically through searches of SCIELO articles, journals, epidemiological bulletins, and data from DATASUS and the amount of underreporting identically reported in the study period. The results obtained showed a similarity between the data analyzed in the years 2019 and 2022, however, there was a relevant discontinuity between the intervals of 2020 and 2 021. It is concluded that this fact is about underreporting of cases during the period of greatest incidence of the SARS-CoV-2 virus, influenced by the changes that the pandemic brought to the fore in the spheres of society, politics, economy, and especially the entire area of health, because during the pandemic period, it was identified that the main attention of Brazilian health was focused on solving or reducing the damage caused by a new virus and neglecting health promotion and prevention actions for endemic diseases in our territory, such as dengue.

Funding: Floristic identification in plots in the RAINFOR forest monitoring network have been supported by the Natural Environment Research Council (grants NE/B503384/1, NE/ D01025X/1, NE/I02982X/1, NE/F005806/1, NE/D005590/1 and NE/I028122/1) and the Gordon and Betty Moore Foundation. In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics. Publisher PDF

A more complete picture of the function of plants in ecosystems results from understanding biotic interactions and this study examined the interactions between ferns and foliicolous lichens. A sampling method involving 15-h walks in each of two tropical forests in Brazil was employed to assess foliicolous lichen diversity on ferns. The nature of foliicolous lichen-fern interactions, and their relationship with forest types (lowland and submontane) and leaf traits (hairs and leaf area), was investigated. Eleven fern species were found to be hosts to 30 foliicolous lichen taxa. Telmatoblechnum serrulatum and Meniscium longifolium were considered the key hosts harboring a greater number (18 and 12) of lichen taxa, of which five taxa were restricted to these two ferns. Approximately 55% of the foliicolous lichens were found on a single fern host. Thicharia sp. A and Gyalectidium filicinum were the more interactive taxa, occurring on seven and ten host ferns, respectively. The forest type had no influence on the interactions. The foliicolous lichen-host fern network differed significantly from null expectations, and there was no sign of specialization. There was also no variation related to the presence of hairs on the sampled ferns (80% had glabrous leaves) and leaf hairs had no significant influence on lichen diversity. Furthermore, leaf area had no influence on the diversity of lichen species. Our results provide a first picture of diversity of foliicolous lichens on fern assemblages in tropical forests. However, there are uncertainties about the mechanisms driving these interactions so more research is needed.

Aim: To (a) assess the environmental suitability for rainforest tree species of Moraceae and Urticaceae across Amazonia during the Mid-Late Holocene and (b) determine the extent to which their distributions increased in response to long-term climate change over this period. Location: Amazonia. Taxon: Tree species of Moraceae and Urticaceae. Methods: We used MaxEnt and inverse distance weighting interpolation to produce environmental suitability and relative abundance models at 0.5-degree resolution for tree species of Moraceae and Urticaceae, based on natural history collections and a large plot dataset. To test the response of the Amazon rainforest to long-term climate change, we quantified the increase in environmental suitability and modelled species richness for both families since the Mid-Holocene (past 6,000 years). To test the correlation between the relative abundance of these species in modern vegetation versus modern pollen assemblages, we analysed the surface pollen spectra from 46 previously published paleoecological sites. Results: We found that the mean environmental suitability in Amazonia for species of Moraceae and Urticaceae showed a slight increase (6.5%) over the past 6,000 years, although southern ecotonal Amazonia and the Guiana Shield showed much higher increases (up to 68%). The accompanied modelled mean species richness increased by as much as 120% throughout Amazonia. The mean relative abundance of Moraceae and Urticaceae correlated significantly with the modern pollen assemblages for these families. Main Conclusions: Increasing precipitation between the Mid- and Late Holocene expanded suitable environmental conditions for Amazonian humid rainforest tree species of Moraceae and Urticaceae, leading to rainforest expansion in ecotonal areas of Amazonia, consistent with previously published fossil pollen data.

1. Plant functional traits impact the fitness and environmental niche of plants. Major plant functional types have been characterized by their trait spectrum, and the environmental and phylogenetic imprints on traits have advanced several ecological fields. Yet, very few trait data on epiphytes, which represent almost 10% of vascular plants, are available. 2. We collated 76,561 trait observations for 2,882 species of vascular epiphytes and compared these to non-epiphytic herbs and trees to test hypotheses related to how the epiphytic habit affects traits, and if epiphytes occupy a distinct region in the global trait space. We also compared variation in traits among major groups of epiphytes, and investigated the coordination of traits in epiphytes, ground-rooted herbs and trees. 3. Epiphytes differ from ground-rooted plants mainly in traits related to water relations. Unexpectedly, we did not find lower leaf nutrient concentrations, except for nitrogen. Mean photosynthetic rates are much lower than in ground-rooted plants and lower than expected from the nitrogen concentrations. Trait syndromes clearly distinguish epiphytes from trees and from most non-epiphytic herbs. 4. Among the three largest epiphytic taxa, orchids differ from bromeliads and ferns mainly by having smaller and more numerous stomata, while ferns differ from bromeliads by having thinner leaves, higher nutrient concentrations, and lower water content and water use efficiency. 5. Trait networks differ among epiphytes, herbs and trees. While all have central nodes represented by SLA and mass-based photosynthesis, in epiphytes, traits related to plant water relations have stronger connections, and nutrients other than potassium have weaker connections to the remainder of the trait network. Whereas stem-specific density reflects mechanical support related to plant size in herbs and trees, in epiphytes it mostly reflects water storage and scales with leaf water content. 6. Synthesis. Our findings advance our understanding of epiphyte ecology, but we note that currently mainly leaf traits are available. Important gaps are root, shoot and whole plant, demographic and gas exchange traits. We suggest how future research might use available data and fill data gaps. ISSN:0022-0477

Dynamic nucleophilic aromatic substitution of tetrazines (SNTz) has been used for the synthesis of dynamic covalent polymer networks that take advantage of both the reversible nature of the reaction and the versatility of the tetrazine ring. Polymer microspheres were easily synthesized and they were proved to be degraded either by UV irradiation or by a chemical stimulus, recovering the original monomer, which allows an efficient recycling. It was also possible to convert one polymer into another one (metamorphosis) by irreversible exchange of monomers. Additionally, the backbone of the polymers could be reduced/oxidized or postfunctionalized with polar groups by the inverse electron demand Diels–Alder (IEDDA) reaction, which not only locked the exchange but also allows for the modulation of the polymer properties, such as solubility in water. Tetrazine dynamic polymers are a recyclable and highly versatile kind of material that enables postsynthetic modulation of their properties as well as provides novel chemical methods and photodegradation., This work was financially supported by Ministerio de Ciencia e Innovación (PGC2018-094503-B-C21). D.S.R. thanks Ministerio de Ciencia, Innovación y Universidades for his FPU fellowship. E.M.-E. acknowledges his current contract financed by Cabildo de Tenerife, Program TF INNOVA 2016-21 (with MEDI & FDCAN Funds). T.S. thanks Universidad de La Laguna for his postdoctoral contract financed by Consejería de Economía, Conocimiento y Empleo for the execution of actions to boost R & D & I activities, Campus de Excelencia Internacional, CEI-Canarias-ULL (SD-20/05). All of the authors thank SEGAI-ULL and SDS-IPNA, and they are particularly grateful to Nieves M. Rodríguez and Manuel Cabrera for their technical support in this research and to Sergio Fajardo and Elena Pastor for their assistance with the electrochemical measurements. The authors also acknowledge the use of Servicio de Análisis Térmico (SAT) of CEQMA (CSIC).

Interleukin 7 (IL-7) and IL-7 receptor (IL-7r) are essential for T lymphocyte differentiation, by driving proliferation and survival of specific developmental stages. While early T lineage progenitors (ETP), the most immature thymocyte population known, have a history of IL-7r expression, it is unclear whether IL-7r is required at this stage. Here, we show that mice lacking IL-7 or IL-7r have a marked loss of ETPs that results mostly from a cell-autonomous defect in proliferation and survival, although no changes were detected in Bcl2 protein levels. Further, a fraction of ETPs responded to IL-7 stimulation ex vivo by phosphorylating Stat5, and IL-7r was enriched in the most immature Flt3+Ccr9+ ETPs. Consistently, IL-7 promoted the expansion of Flt3+ but not Flt3-ETPs on OP9-DLL4 cocultures, without affecting differentiation at either stage. Taken together, our data show that IL-7/IL-7r is necessary following thymus seeding, by promoting proliferation and survival of the most immature thymocytes.SummaryPaiva et al. show that IL-7/IL-7r signaling upon thymus seeding is essential for proliferation and survival of the most immature early T lineage progenitors (ETP), thereby determining the physiological ETP cellularity.

A taxa de sobrevivencia de mudas de castanha ( Bertholletia excelsa Bonpl.) pode ser fortemente ameacada pela predacao de roedores silvestres. O objetivo deste trabalho foi avaliar a predacao de mudas de castanha por roedores em area de pastagem abandonados durante um intenso processo de restauracao florestal sob diferentes tratamentos silviculturais. Foram realizados tres tipos de tratamentos diferentes: tratamento 1 (T1) - tratamento silvicultural fisico; tratamento 2 (T2) - tratamentos silviculturais fisico e quimico; tratamento 3 (T3) - tratamentos silviculturais fisico e quimico com protecao de mudas (garrafa pet) como barreira fisica contra a predacao de roedores . Foi quantificado o numero de plantas danificadas e predadas por roedores, e por outros fatores. Os resultados dos tratamentos foram comparados com base nos testes de normalidade e t de Student a 1%. Encontramos diferencas significativas entre os tratamentos. A mortalidade causada por roedores no Tratamento 1 foi de 27,5% e para outros fatores foi de 25,1%. Nao encontramos predacao por roedores no Tratamento 2 e 3, e a mortalidade causada por outros fatores foi de 4,2% e 14,1%, respectivamente. Constatamos que a alta taxa de predacao no Tratamento 1 esta diretamente associada ao crescimento de gramineas forrageiras por falta de tratamento quimico, que proporcionam um ambiente seguro para os roedores, oferecendo menor risco para que os roedores em relacao aos seus predadores. A conclusao e que na restauracao de areas de pastagens abandonadas, o controle da forrageira pre-existente nos anos iniciais deve ser feito por capina quimica (herbicida), embora com custo mais elevado, para evitar o ataque de roedores, a competicao das mudas com o capim e, principalmente, o custo final da restauracao. Palavras-chave : restauracao produtiva, pastagem abandonada, herbicida, castanheira do brasil, predacao por roedores, custo da restauracao, Amazonia.

A single loop-mediated isothermal amplification (LAMP) assay was developed for specific detection of both pathogens that cause bacterial blight in common bean, Xanthomonas phaseoli pv. phaseoli (Xpp) and Xanthomonas citri pv. fuscans (Xcf). The objective was to provide a simple, easy-to-use, specific, and sensitive method to investigate the presence of one or both pathogens in plant material and seeds for routine diagnosis. The detection limits for both pathogens were 10 CFU/ml for cell suspensions and 1 fg of DNA, whereas in conventional PCR, the primers detected up to 105 CFU/ml and 1 ng of DNA. Specificity was confirmed by testing DNA from bean leaves, other Xanthomonas species, common fungal and bacterial bean pathogens, and bacteria from the leaf microbiota. The method was tested with bean leaves inoculated with Xpp, and the pathogen could be detected from 4 h up to 15 days postinoculation, even before disease symptoms were visible. When the method was applied to bacterium detection (Xpp or Xcf) in seed lots from infected plants, the bacterium detection rate was 100% (24 of 24). The pathogens were detected in seeds incubated for just 1 h in saline solution (0.85%), reducing the time needed for bacterium detection. The LAMP assay could be useful as a tool in bean bacterial blight management. Rapid and sensitive detection of bacteria in bean seed lots would reduce the risks of planting highly contaminated seeds in environments favorable to blight multiplication.

Climate change is a global phenomenon that affects biophysical systems and human well-being. The Paris Agreement of the United Nations Framework Convention on Climate Change entered into force in 2016 with the objective of strengthening the global response to climate change by keeping global temperature rise this century well below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 °C. The agreement requires all Parties to submit their “nationally determined contributions” (NDCs) and to strengthen these efforts in the years ahead. Reducing carbon emissions from deforestation and forest degradation is an important strategy for mitigating climate change, particularly in developing countries with large forests. Extensive tropical forest loss and degradation have increased awareness at the international level of the need to undertake large-scale ecological restoration, highlighting the need to identify cases in which restoration strategies can contribute to mitigation and adaptation. Here we consider Brazil as a case study to evaluate the benefits and challenges of implementing large-scale restoration programs in developing countries. The Brazilian NDC included the target of restoring and reforesting 12 million hectares of forests for multiple uses by 2030. Restoration of native vegetation is one of the foundations of sustainable rural development in Brazil and should consider multiple purposes, from biodiversity and ecosystem services conservation to social and economic development. However, ecological restoration still presents substantial challenges for tropical and mega-diverse countries, including the need to develop plans that are technically and financially feasible, as well as public policies and monitoring instruments that can assess effectiveness. The planning, execution, and monitoring of restoration efforts strongly depend on the context and the diagnosis of the area with respect to reference ecosystems (e.g., forests, savannas, grasslands, wetlands). In addition, poor integration of climate change policies at the national and subnational levels and with other sectorial policies constrains the large-scale implementation of restoration programs. The case of Brazil shows that slowing deforestation is possible; however, this analysis highlights the need for increased national commitment and international support for actions that require large-scale transformations of the forest sector regarding ecosystem restoration efforts. Scaling up the ambitions and actions of the Paris Agreement implies the need for a global framework that recognizes landscape restoration as a cost-effective nature-based solution and that supports countries in addressing their remaining needs, challenges, and barriers.

Made available in DSpace on 2021-06-25T10:27:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The forests of Amazonia are among the most biodiverse plant communities on Earth. Given the immediate threats posed by climate and land-use change, an improved understanding of how this extraordinary biodiversity is spatially organized is urgently required to develop effective conservation strategies. Most Amazonian tree species are extremely rare but a few are common across the region. Indeed, just 227 ‘hyperdominant’ species account for >50% of all individuals >10 cm diameter at 1.3 m in height. Yet, the degree to which the phenomenon of hyperdominance is sensitive to tree size, the extent to which the composition of dominant species changes with size class and how evolutionary history constrains tree hyperdominance, all remain unknown. Here, we use a large floristic dataset to show that, while hyperdominance is a universal phenomenon across forest strata, different species dominate the forest understory, midstory and canopy. We further find that, although species belonging to a range of phylogenetically dispersed lineages have become hyperdominant in small size classes, hyperdominants in large size classes are restricted to a few lineages. Our results demonstrate that it is essential to consider all forest strata to understand regional patterns of dominance and composition in Amazonia. More generally, through the lens of 654 hyperdominant species, we outline a tractable pathway for understanding the functioning of half of Amazonian forests across vertical strata and geographical locations. Institute of Environment Department of Biological Sciences Florida International University School of Geography University of Leeds Center for Global Discovery and Conservation Science Arizona State University Instituto Nacional de Pesquisas da Amazônia (INPA) Ecology and Evolutionary Biology University of Michigan Departamento de Ciencias Forestales Universidad Nacional de Colombia Departamento de Biología Universidad Autónoma de Madrid Centro de Investigación en Biodiversidad y Cambio Global (CIBC-UAM) Universidad Autónoma de Madrid Naturalis Biodiversity Center Systems Ecology Vrije Universiteit Lancaster Environment Centre Lancaster University Environmental Change Institute University of Oxford Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences School of Geosciences University of Edinburgh Missouri Botanical Garden Brazilian Agricultural Research Corporation (Embrapa) Universidad Nacional de San Antonio Abad del Cusco Department of Intergrative Biology University of California Berkeley Department of Biology University of Turku Instituto de Investigaciones de la Amazonía Peruana UNELLEZ-Guanare Programa de Ciencias del Agro y el Mar Herbario Universitario (PORT) Compensation International Progress S. A.—Ciprogress Greenlife AMAP Université de Montpellier CIRAD CNRS INRAE IRD Environmental and Rural Science University of New England INRA UMR EcoFoG AgroParisTech CNRS CIRAD Université des Antilles Université de Guyane CIRAD UMR EcoFoG BIOMAS Universidad de Las Américas Instituto de Ecología Herbario Nacional de Bolivia Departamento de Biologia Universidade Federal de Rondônia Laboratoire Evolution et Diversité Biologique (EDB) CNRS/UPS School of Geography Earth and Environmental Sciences University of Plymouth Department of Ecology and Evolutionary Biology Cornell University Department of Geography University of Exeter Facultad de Ciencias Biológicas Universidad Nacional de la Amazonía Peruana Estación Biológica del Jardín Botánico de Missouri Institut de Ciència i Tecnologia Ambientals Universitat Autònoma de Barcelona School of Geography & Sustainable Development University of St Andrews Department of Environment and Development Federal University of Amapá Centre for Tropical Environmental and Sustainability Science (TESS) and College of Marine and Environmental Sciences James Cook University Department of Environmental Science and Policy George Mason University Inventory and Monitoring Program National Park Service Smithsonian Institution Department of Plant Sciences University of Cambridge Living with Lakes Centre Laurentian University DRGB Instituto Nacional de Innovación Agraria (INIA) Herbarium Amazonense (AMAZ) Universidad Nacional de la Amazonia Peruana Department of Ecology Universidade de São Paulo Institute for Biodiversity and Ecosystem Dynamics University of Amsterdam Centro de Estudos da Biodiversidade Universidade Federal de Roraima Museo de Historia Natural Noel Kempff Mercado Universidad Autónoma Gabriel Rene Moreno Faculdade de Ciências Agrárias Biológicas e Sociais Aplicadas Universidad do Estado de Mato Grosso Centro de Biociências Universidade Federal do Rio Grande do Norte Department of Ecology Evolution and Behaviour University of Minnesota Department of Geography University College London Departamento de Ciencias Biológicas Universidad de Los Andes (Colombia) Centro de Ciências Biológicas e da Natureza Universidade Federal do Acre Nicholas School of the Environment Duke University Iwokrama International Centre for Rainforest Conservation and Development Smithsonian’s National Zoo & Conservation Biology Institute Instituto de Ciencias Naturales Universidad Nacional de Colombia Universidade Federal Rural da Amazônia—UFRA/CAPES Museu Paraense Emílio Goeldi Laboratorio de Ecología de Bosques Tropicales y Primatología Fundación Natura Colombia Universidad de Los Andes Facultad de Forestales Universidad Nacional de la Amazonía Peruana Institute of Research for Forestry Development Universidad de los Andes School of Environmental and Forest Sciences (SEFS) University of Washington Universidad Regional Amazónica Ikiam Agteca-Amazonica Universidad Autónoma del Beni Instituto Amazónico de Investigaciones (IMANI) Universidad Nacional de Colombia Broward County Parks and Recreation Biological Sciences Florida Atlantic University-Davie Museu Universitário Universidade Federal do Acre Facultad de Ingeniería Ambiental Universidad Estatal Amazónica Department of Biology Washington University in St Louis National Institute for Space Research (INPE) Geoinformática & Sistemas (GeoIS) School of Earth Sciences and Environmental Sustainability Northern Arizona University Department of Geography and the Environment University of Texas at Austin Instituto de Ciência e Tecnologia São Paulo State University (UNESP) School of Anthropology and Conservation University of Kent Universidade Federal do Amazonas Herbario Alfredo Paredes (QAP) Universidad Central del Ecuador School of Geography Earth and Environmental Sciences University of Birmingham Department of Life Sciences Imperial College London Science and Education The Field Museum Universidad Tecnica del Norte Herbario Nacional del Ecuador Research Institute Alexander von Humboldt Instituto de Ciência e Tecnologia São Paulo State University (UNESP)

School dropout is a problem that must be tackled in every educational institution, because, in addition to the evaded student causing loss of public investment made in it, the community loses a student who could contribute professionally to their education. Thus, this study has as its general objective: to develop a management process capable of reducing dropout, and as specific objectives: to understand the factors that contribute to dropout; Know the IFPI's strategic planning (PDI) and the institution's objectives related to dropout, check how the institution has dealt with the dropout problem and identify solutions to reduce dropout through management processes. To meet these objectives, a qualitative research was conducted in October 2018, through a case study with 10 employees who hold different positions in the management of the Parnaíba campus of the Federal Institute of Piauí (IFPI). The research approach is qualitative and it is also classified as action research. The results of this research showed 11 main reasons for the student to evade, especially the lack of transportation, due to the campus location, a process of connection between the sectors, academic control, pedagogical sector, and others was also suggested, with supervision of the coordination. La deserción escolar es un problema que debe ser abordado en toda institución educativa, porque, además de que el alumno desertor provoque la pérdida de la inversión pública que se hace en él, la comunidad pierde un alumno que podría contribuir profesionalmente con su educación. Así, este estudio tiene como objetivo general: desarrollar un proceso de gestión capaz de reducir la deserción, y como objetivos específicos: comprender los factores que contribuyen al abandono escolar; conocer la planificación estratégica (PDI) de la IFPI y los objetivos de la institución relacionados con la evasión, verificar cómo la institución ha abordado el problema de la evasión e identificar soluciones para reducir la evasión a través de procesos de gestión. Para cumplir con estos objetivos, en octubre de 2018 se realizó una investigación cualitativa, a través de un estudio de caso con 10 funcionarios que ejercen diferentes cargos en la gestión del campus Parnaíba del Instituto Federal de Piauí (IFPI). El enfoque de investigación es cualitativo y también se clasifica como investigación-acción. Los resultados de esta investigación arrojaron 11 razones principales para que el estudiante eluda, destacando principalmente la falta de transporte, debido a la ubicación del campus, un proceso de conexión entre los sectores, control académico, sector pedagógico, y otros, con supervisión de la coordinación. A evasão escolar é uma problemática que deve ser combatida em toda instituição de ensino, pois, além do aluno evadido causar perda do investimento público feito nele, a comunidade perde um aluno que poderia contribuir profissionalmente com sua formação. Assim, este estudo tem como objetivo geral: desenvolver um processo gerencial capaz de reduzir a evasão, e como objetivos específicos: compreender os fatores que contribuem para a evasão escolar; conhecer o planejamento estratégico do IFPI (PDI) e os objetivos da instituição relacionados a evasão, verificar como a instituição tem lidado com o problema da evasão e identificar soluções para reduzir a evasão por meio de processos gerenciais. Para atender esses objetivos, foi realizada uma pesquisa qualitativa em outubro de 2018, por meio de um estudo de caso com 10 servidores que exercem diferentes cargos na gestão do campus Parnaíba do Instituto Federal do Piauí (IFPI). A abordagem da pesquisa é qualitativa e a mesma classifica-se também como pesquisa-ação. Os resultados desta pesquisa mostraram 11 principais motivos do aluno evadir, destacando-se principalmente a falta de transporte, devido a localização do campus, também foi sugerido um processo de ligação entre os setores, controle acadêmico, setor pedagógico, e outros, com supervisão da coordenação.

Global patterns of species and evolutionary diversity in plants are primarily determined by a temperature gradient, but precipitation gradients may be more important within the tropics, where plant species richness is positively associated with the amount of rainfall. The impact of precipitation on the distribution of evolutionary diversity, however, is largely unexplored. Here we detail how evolutionary diversity varies along precipitation gradients by bringing together a comprehensive database on the composition of angiosperm tree communities across lowland tropical South America (2,025 inventories from wet to arid biomes), and a new, large-scale phylogenetic hypothesis for the genera that occur in these ecosystems. We find a marked reduction in the evolutionary diversity of communities at low precipitation. However, unlike species richness, evolutionary diversity does not continually increase with rainfall. Rather, our results show that the greatest evolutionary diversity is found in intermediate precipitation regimes, and that there is a decline in evolutionary diversity above 1,490 mm of mean annual rainfall. If conservation is to prioritise evolutionary diversity, areas of intermediate precipitation that are found in the South American ‘arc of deforestation’, but which have been neglected in the design of protected area networks in the tropics, merit increased conservation attention.

We aimed to evaluate the changes in biochemical metabolism generated by salt stress and to investigate the effect of brassinosteroids in mitigating of this stress on two cultivars of Vigna unguiculata L. We used a completely randomized experimental design in a 2 x 3 x 3 factorial scheme, using two cultivars of cowpea (BRS Guariba and BR3 Tracuateua - moderately tolerant and sensitive to salinity, respectively), three concentrations of brassinosteroids (0, 0.2 and 0.4 μM Br) and three concentrations of NaCl (0 , 50 and 100 mM NaCl), with four replicates. The following evaluations were carried out: relative water content, electrolyte leakage, nitrate levels, nitrate reductase activity, free ammonium, total soluble amino acids, soluble proteins, glycine betaine and proline. The results showed that salinity at 100 mM affected the nitrate reductase enzyme activity, the relative water content, total soluble amino acids and soluble proteins for cultivars BR3 Tracuateua, and BRS Guariba, but the 24-epibrassinolid attenuated the effects of salinity for these variables. The concentration of 0.2 μM of Br increased 55% and 20% in proline and glycine betaine contents, respectively, in both of cultivars. The plants under stress saline and 0.2 mM of 24-epibrassinolid, presented 42% and 58% reductions in electrolyte leakage of BR3 Tracuateua and BRS Guariba cultivars, respectively. The concentrations of ammonium were slightly varied. Therefore, the application of 0.2 μM of 24-epibrassinolid caused a greater acclimatization of the cultivars, being the BR3 Tracuateua (sensitive to salt) cultivar more expressive in most treatments.

T lymphocyte differentiation in the thymus relies on high cellular turnover, and cell competition enforces thymocyte replenishment. If deprived of competent progenitors, the thymus can maintain thymopoiesis autonomously for several weeks but this bears a high risk of leukemia. Here we show that double negative 3 early (DN3e) thymocytes can acquire stem cell like properties, which enables them to maintain thymopoiesis. Specifically, DN3e proved to be long-lived, they proliferated and differentiated in vivo, were necessary for autonomous thymopoiesis, and included DNA-label-retaining cells. Single cell RNAseq revealed a transcriptional program of thymopoiesis similar in autonomy and the controls. Nevertheless, a new population was identified in thymus autonomy that was enriched for an aberrant Notch target gene signature and bypassed the β−selection checkpoint. In sum, DN3e have the potential to self-renew and differentiate in vivo if cell competition is compromised but this enables the accumulation of atypical cells, probably leading to leukemia.