29 research outputs found

    Modificações em parametros fisicos e quimicos de latossolos argilosos decorrentes da substituição da floresta amazonica e do cerrado por pastagens

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    Orientador: Carlos Roberto EspindolaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia AgricolaResumo: A cobertura vegetal brasileira vem sofrendo sensíveis modificações devido a sucessivas intervenções humanas. Importantes ecossistemas, como a Floresta Amazônica e o Cerrado, vêm perdendo boa .parte de suas coberturas vegetais originais, em função do desmatamento, cedendo lugar a atividades predominantemente agricolas. Não só a biodiversidade desses ecossistemas tem sido afetada, mas também seus solos, que costumam sofrer uma degradação de suas propriedades originais, notadamente da estrutura/agregação e suas relações com a matéria.orgânica. No caso de solos sob florestas, importantes contingentes de húmus deixam de ser incorporados a seus componentes. É previsível que o efeito de diferentes coberturas, suas remoções e cultivo transmitam ao solos distintos efeitos e problemas. Neste sentido, o .presente trabalho objetivou avaliar os impactos decorrentes da remoção das coberturas originais, e seu posterior uso agrícola, tomando, para tanto, duas distintas condições fisio.gráficas brasileiras - Cerrado e Floresta Amazônica, tendo como atributos primordiais de análise a evolução da matéria orgânica ligada às modificações da estrutura/agregação dos solos. As áreas selecionadas para as investigações foram Porto Velho/RO (floresta) e Senador Canedo/GO (cerrado) de ocorrência de latossolos argilosos, cujas amostras foram coletadas ao longo de transeções contendo 24 pontos (pequenas trincheiras de 60 cm de profundidade), 12 sob vegetação natural (floresta e cerrado) e 12 sob pastagem plantada, em cada uma das áreas de estudo; em seguida, estas foram analisadas quanto à distribuição e estabilidade de agregados em água, granulometria complexo trocável. fracionamento químico da matéria orgânica, carbono orgânico, nitrogênio total e relação C/N. Os resultados foram analisados estatisticamente de formas distintas: estatística descritiva, valores médios das parcelas e correlações de Xlll substâncias orgânicas e inorgânicas, visando à discussão mais aprimorada dos resultados. Sobre o diâmetro médio ponderado dos agregados (DMP) pôde se observar uma diminuição acentuada no sentido vegetação natural-pastagem, sendo mais pronunciada na região do cerrado; de maneira .geral, os maiores valores foram observados na região amazônica. Os resultados obtidos para a análise granulométrica não revelaram sensíveis variações em seu conteúdo, quando se comparam os ecossistemas e as formas de manejo estudados. Os coeficientes de variação encontrados foram baixos, revelando uma certa homogeneidade dos resultados analíticos obtidos. A análise da fertilidade revelou diferenças significativas, entre os cossistemas, para pH, T, YO,lo, S, P, K, Mg e H+Al, mostrando, em ambos os casos, baixa fertilidade natural; observou-se maior acúmulo de matéria orgânica, P, Ca, Mg e T nos horizontes superficiais dos dois ecossistemas estudados. O nitrogênio total e o carbono orgânico apresentaram comportamento similar, podendo se observar, na mudança da condição de vegetação natural para pastagem, uma diminuição significativa nos teores desses elementos; os maiores valores foram encontrados no horizonte superficial no solo sob floresta amazônica, revelando uma queda brusca deste para o horizonte subjacente.Os valores de ácido fiílvico (AF), ácido húmico (Ali) e humina, de aneira.geral, foram superiores na região amazônica, em ambas as fundidades estudadas. No sentido vegetação natural-pastagem, observou-se um decréscimo no AF e na humina, enquanto que -para o AH tal comportamento não se manifestou; observou-se um acúmulo das três frações nos horizontes superficiais. Pelo presente, .pode se observar que a remoção da cobertura vegetal original promoveu efeitos negativos sobre os atributos dos solos estudados, notadamente sobre a estrutura/agregação dos mesmos, ligados à diminuição do carbono total. Isso mostra a grande fragilidade dos solos dos ecossistemas brasileiros, quando submetidos ao cultivo, a partir da comparação com suas condições naturais. Assim, para estas áreas ou áreas similares com latossolos argilosos, o manejo agricola deve prever tecnicas que procurem minimizar os efeitos negativos estudadosAbstract: Brazil is considered one of the richest countries in flora with about 60.000 species,..from about 22.0.000 recognised among the Angiosperms. The large. extension ofthe country (more than 8.500.000 km2) and the great diversity ofthe climate, soils and conditions promote as final result, a wide vegetation variety. The Amazon Forest, represented by the. .hydrographical basing a the Amazon River with Tocantins / Araguaia, includes 70 millions of kni2 which (50 millions are forested), representing about 56% ofthe Brazilian Territory (480 millions ofhectares). From 50 millions o( Km ITomthe. Brazilian Llega Amazon 76% were originally coyeredby forest. From original vegetable cover, 415.000 km2 were changed by the man (until 1990) equivalent to 10,5% ofthe original forest. The Brazilian's "cerrado" include an area about 200 millions of hectares (23% of Brazilian territory), 60% of which showing agricultural aptness being considered, afier Amazon Forest, the most important Brazilian ecosystem in dimension. Today is repealing. about 27% of national cereal production and 42% of the national.population of cattle of boviM, with the original vegetable cover ample changed. The aim of the present work is to evaluate the effects of the human intervention, through the jungle clearing and the cultivation in the some physical, chemical and biochemical soil's properties of these important Brazilian ecosystems. This research was installed in Porto Velho, State of Rondônia and Senador Canedo, State of Goiás; the first site located vicinity of the Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) where the annual average tt.mperature is 25,50 C and precipitation of2.300 mm; and in the vicinity of Goiânia vicinity the Empresa Goiana de Pesquisa Agropecuária (EMGOPA) whit annual average temperature about 220 C, and precipitation of 1.200 mm, including a dry period ftom May to October. The predominant natural vegetation was classificated as a tropical forest and "cerrado". Before, the samples were accomplished in areas of primary vegetation and planted pasture, obeying a line with 24 points each 10 metres (12 under natural vegetation and 12 under.pasture) in each local of study. Samples were taken out ftom the superficial and subsuperficial horizon, so that in each samplings point smaIl ditches were opened (approximately 60 cm deep) for summarised description In the border lines, pedons with 160 em deep (vertical outline) were studied (morphologieal deseriptions and sampling). ColIected sampJes were analysed for the stability of aggregates in water, changeable complex, organic matter compounds and texture. In relation to the aggregate distribution the results showed that a redmtion when the soil under native vegetation was submitted to agricultural cultivation, thought, the amazon region.presented high aggregation size. The results obtained for particIe size analysis did not show modifications in the contents within the studied conditions. The soils showed, general by Jarge, that the chemical composition was lower, but the correlation between ecosystems was significant. .The higher organic compounds (N-total, c-Organic and matter organic ftactions), in the superficial horizon ofnatural vegetation, wintry in Amazon Forest, were observed. The results obtained in this study confmn a certain soil degradation cultivated soils (by introduction of pasture) compared with uncultivated soils in two Brazilian's ecosystems (Arnazon Forest and "cerrado"). These changes may be of a chemical, biochemieal or physical natureDoutoradoAgua e SoloDoutor em Engenharia Agrícol

    Environmental impacts of land use and occupation in subbasins of Campinas, São Paulo, Brazil

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    Changes promoted by anthropic actions in ecosystems located in urban habitats have generated the destruction of areas of great environmental importance, such as that occurring in small river basins that have suffered as a consequence of constant episodes of floods. This research discusses the consequences of land use and occupation on the soil attributes studied, thus allowing a broader discussion of the relationships between urban expansion and the reduction of vegetation areas and permeable areas in urban sub - basins. Thus, the subbasins Rio das Pedras and Baixo Anhumas, located in Campinas, São Paulo, were chosen as the study area. In the year 2014, 37 points were analyzed along the same lines, in order to characterize them from the environmental point of view, also collecting samples of deformed and undisturbed soil for laboratory analysis, besides the performance of tests of mechanical resistance to penetration, using a penetrometer. In general, the analyzed sub basins have been suffering over the years processes of fragilization of their ecosystems. This scenario of anthropic soil impacts in both basins allows us to infer that the urban occupation was directly responsible for the alterations and environmental disturbances suffered in the area

    Avaliação do consumo de água em torneiras em ambiente universitário

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    Atualmente, o consumo de água está na agenda da maioria das organizações ao redor do mundo. Além dos benefícios ambientais advindos do uso dos recursos naturais, há também motivações financeiras para continuamente reduzir os custos operacionais.  Neste artigo são apresentados os resultados das medições feitas em torneiras na Pontifícia Universidade Católica de Campinas. As medições foram obtidas automaticamente através de uma rede de sensores sem fio, mediante o uso de dispositivos Rfbee e Xbee, especificamente desenvolvidos para coletar os dados. Os principais resultados mostram que o consumo de água é alto e que medidas devem ser tomadas para reduzir o consumo de água para menos de 5 litros por minuto

    Differential transcription of virulence genes in Aggregatibacter actinomycetemcomitans serotypes

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    Background: Aggregatibacter actinomycetemcomitans serotypes are clearly associated with periodontitis or health, which suggests distinct strategies for survival within the host.\ud Objective: We investigated the transcription profile of virulence-associated genes in A. actinomycetemcomitans serotype b (JP2 and SUNY 465) strains associated with disease and serotype a (ATCC 29523) strain associated with health. Design: Bacteria were co-cultured with immortalized gingival epithelial cells (OBA-9). The adhesion efficiency\ud after 2 hours and the relative transcription of 13 genes were evaluated after 2 and 24 hours of interaction. Results: All strains were able to adhere to OBA-9, and this contact induced transcription of pgA for polysaccharide biosynthesis in all tested strains. Genes encoding virulence factors as Omp29, Omp100, leukotoxin, and CagE (apoptotic protein) were more transcribed by serotype b strains than by serotype a. ltxA and omp29, encoding the leukotoxin and the highly antigenic Omp29, were induced in serotype b by\ud interaction with epithelial cells. Factors related to colonization (aae, flp, apaH, and pgA) and cdtB were upregulated in serotype a strain after prolonged interaction with OBA-9.\ud Conclusion: Genes relevant for surface colonization and interaction with the immune system are regulated differently among the strains, which may help explaining their differences in association with disease.FAPESP - 03/08598-0FAPESP - 05/58903-

    Análise da morfométrica de agregados do solo em áreas mineradas em diferentes estágios de recuperação na Amazônia

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    Mining has a strong influence on the Brazilian economy, however, extractive activity results in multiple damages to the ecosystem, as vegetation and the surface layer of the soil are removed, altering the natural pedological characteristics. Therefore, programs for the recovery of degraded areas become essential to mitigate or compensate for negative impacts on the environment. In this way, the understanding of soil quality indicators has been worked on to evaluate the process of recovery of degraded areas. Thus, the objective of this work was to develop and test a new approach to qualify the recovery of soil aggregation and reference ecosystems in the Brazilian Amazon (RO). For this, the geometric mean diameter (DMG) and the morphometric parameters: area, circularity, roundness and Feret diameter of the soil aggregates were determined. The parameters were evaluated in five different aggregate sizes, 6.0 mm, 4.0 mm, 2.0 mm, 1.0 mm and 0.71 µm, then multivariate analysis of variance (MANOVA) was performed, comparing the morphometric variables and aggregate sizes from each study area. The results obtained show a positive correlation between the values ​​of area, circularity and Feret diameter of soil aggregates, indicating improvements in soil structure and vegetation. In this way, the proposed parameters demonstrated a high capacity to describe the soil quality and differentiate the recovery levels, presenting itself as an excellent indicator in the monitoring of degraded areas.A mineração exerce forte influência sobre a economia brasileira, no entanto, a atividade extrativista resulta em múltiplos danos ao ecossistema, pois a vegetação e a camada superficial do solo são removidas, alterando as características pedológicas naturais. Portanto, programas de recuperação de áreas degradadas tornam-se essenciais para mitigar ou compensar os impactos negativos ao meio ambiente. Dessa forma, o entendimento dos indicadores de qualidade do solo tem sido trabalhado para avaliar o processo de recuperação de áreas degradadas. Assim, o objetivo deste trabalho foi desenvolver e testar uma nova abordagem para qualificar a agregação do solo em recuperação e ecossistemas de referências na Amazônia brasileira (RO). Para isso, determinou-se o diâmetro médio geométrico (DMG), e os parâmetros morfométricos: área, circularidade, arredondamento e diâmetro de Feret dos agregados do solo. Os parâmetros foram avaliados em cinco tamanhos de agregados diferentes, 6,0 mm, 4,0 mm, 2,0 mm, 1,0 mm e 0,71 µm, em seguida foi realizada análise de variância multivariada (MANOVA), comparando as variáveis morfométricas e tamanhos dos agregados de cada área de estudo. Os resultados obtidos mostram uma correlação positiva entre os valores da área, circularidade e diâmetro de Feret dos agregados do solo, indicando melhorias na estrutura do solo e na vegetação. Dessa forma, os parâmetros propostos demonstraram alta capacidade de descrever a qualidade do solo e diferenciar os níveis de recuperação, apresentando-se como um excelente indicador no monitoramento de áreas degradadas

    Degradação ambiental e qualidade da água em nascentes de rios urbanos

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    A qualidade de um curso hídrico está diretamente relacionada às alterações verificadas na bacia hidrográfica. O uso e ocupação do solo exercem fundamental influência no escoamento superficial para estes cursos, podendo alterar sua qualidade e quantidade. O distrito de Barão Geraldo (Campinas/SP) faz parte parcialmente da bacia do Ribeirão das Pedras, que nasce entre o Alto Taquaral e o Jardim Primavera, e que, após passar pela sede do distrito, desemboca na margem esquerda do rio Anhumas. Este, por sua vez, desemboca na margem esquerda do rio Atibaia, importante rio do estado de São Paulo. Este trabalho visou avaliar os impactos ambientais nas nascentes da bacia do Ribeirão das Pedras, a fim de se verificar a qualidade das mesmas por meio da Matriz de Leopold e Índice de Qualidade de Águas (IQA). Por meio de imagens de satélite, carta topográfica e visitas a campo localizaram-se treze nascentes distribuidas ao longo da bacia, sendo aplicado o IQA em seis nascentes principais. A análise do IQA permitiu a classificação de 5 das 6 nascentes como “BOA”, ainda que as mesmas apresentassem irregularidades para alguns parâmetros. Verificou-se pela matriz, que o parâmetro mais impactante nas nascentes era o não cumprimento do raio de mata ciliar, indicando que as medidas a serem tomadas preferencialmente neste momento dizem respeito à sua recuperação

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

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    Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

    Measurement of jet fragmentation in Pb+Pb and pppp collisions at sNN=2.76\sqrt{{s_\mathrm{NN}}} = 2.76 TeV with the ATLAS detector at the LHC

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