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On the relation between Transversal and Longitudinal Scaling in Cities
Given that a group of cities follows a scaling law connecting urban population with socio-economic or infrastructural metrics (transversal scaling), should we expect that each city would follow the same behavior over time (longitudinal scaling)? This assumption has important policy implications, although rigorous empirical tests have been so far hindered by the lack of suitable data. Here, we advance the debate by looking into the temporal evolution of the scaling laws for 5507 municipalities in Brazil. We focus on the relationship between population size and two urban variables, GDP and water network length, analyzing the time evolution of the system of cities as well as their individual trajectory. We find that longitudinal (individual) scaling exponents are city-specific, but they are distributed around an average value that approaches to the transversal scaling exponent when the data are decomposed to eliminate external factors, and when we only consider cities with a sufficiently large growth rate. Such results give support to the idea that the longitudinal dynamics is a micro-scaling version of the transversal dynamics of the entire urban system. Finally, we propose a mathematical framework that connects the microscopic level to global behavior, and, in all analyzed cases, we find good agreement between theoretical prediction and empirical evidence
Pastagens para ovinos.
Espécies forrageiras mais indicadas; Sistema de pastejo; Sistema de pastejo com lotação contínua; Sistema de lotação rotacionada; Com um grupo de animais; Com dois grupos de animais; Creep grazing; Diferido ou protelado; Manejo e lotação da pastagem; Estacionalidade de produção de forragem
Recurrence of multiple meiotic abnormalities in maize genotypes from the same origin and their influence on productivity.
The frequency of meiotic abnormalities among single-, double- and three-way cross experimental hybrids and their parental inbred lines is studied. Among the sixteen inbred lines examined, fifteen originated from populations developed at the National Center of Research in Maize and Sorghum (CNPMS/Embrapa) and one from a population developed at ESALQ (Faculty of Agriculture Luiz de Queiroz of the University of São Paulo). Previous analyses of homozygous and heterozygous maize genotypes from CNPMS populations demonstrated high meiotic instability. The present investigation aims at analyzing the meiotic behavior of different inbred lines obtained from CNPMS populations by another breeding enterprise to verify the presence of the same abnormalities and determine whether the abnormalities might compromise productivity. Analyses showed the presence of some abnormalities described previously, albeit at a lower frequency. The most common abnormalities in homozygous and heterozygous genotypes from CNPMS populations were related to irregular chromosome segregation and to chromosome stickiness. An inbred line from the ESALQ population showed only abnormalities related to irregular chromosome segregation caused by the presence of univalent chromosomes. The Pearson correlation procedure indicated high negative correlation between meiotic abnormalities and productivity
Recurrence of multiple meiotic abnormalities in maize genotypes from the same origin and their influence on productivity.
The frequency of meiotic abnormalities among single-, double- and three-way cross experimental hybrids and their parental inbred lines is studied. Among the sixteen inbred lines examined, fifteen originated from populations developed at the National Center of Research in Maize and Sorghum (CNPMS/Embrapa) and one from a population developed at ESALQ (Faculty of Agriculture Luiz de Queiroz of the University of São Paulo). Previous analyses of homozygous and heterozygous maize genotypes from CNPMS populations demonstrated high meiotic instability. The present investigation aims at analyzing the meiotic behavior of different inbred lines obtained from CNPMS populations by another breeding enterprise to verify the presence of the same abnormalities and determine whether the abnormalities might compromise productivity. Analyses showed the presence of some abnormalities described previously, albeit at a lower frequency. The most common abnormalities in homozygous and heterozygous genotypes from CNPMS populations were related to irregular chromosome segregation and to chromosome stickiness. An inbred line from the ESALQ population showed only abnormalities related to irregular chromosome segregation caused by the presence of univalent chromosomes. The Pearson correlation procedure indicated high negative correlation between meiotic abnormalities and productivity
Unidades de observação de híbridos de milho, em dois espaçamentos entre linhas, na Região de Clima Temperado ? Safra. 2009/10.
bitstream/item/78833/1/Circular-124.pd
Erosive potential of rains in the climate change scenarios in the upper Taquari River Basin, MS, Brazil.
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A seleção de critérios no zoneamento agroecológico: proposta metodológica.
A seleção de critérios espaciais para um trabalho de zoneamento agroecológico envolve critérios de aptidão, biodiversidade, socioeconomia, recursos hídricos, legais, ambientais, políticas etc. É necessário identificar a questão-chave e traçar diretrizes do zoneamento que representem as orientações do setor. Essas diretrizes são econômicas, estratégicas, empresariais, sociais, técnicas e políticas, obtidas em negociação com representantes de diferentes setores da sociedade e, ao fim, ponderar os diversos critérios segundo a importância de cada um, no contexto em análise. Este trabalho tem por objetivo apresentar uma metodologia de identificação coletiva desses critérios com o aporte de recursos de sistemas de suporte à decisão espacial e de planejamento estratégico territorial. A metodologia apresenta as seguintes etapas: diagnóstico estratégico, identificação de critérios determinantes (não ponderáveis), identificação dos critérios a serem ponderados e uma proposta de fluxo de procedimentos para a seleção de critérios espaciais. Visa subsidiar a formulação de políticas públicas de ordenamento territorial do setor rural. O resultado é composto de um conjunto de procedimentos e de uma lista de perguntas-chave para compor os diagnósticos e selecionar os critérios espaciais que podem ser aplicados em trabalhos de planejamento territorial adicionado a visão estratégica
Biocomposite for Prolonged Release of Water-Soluble Drugs
This study aimed to develop a prolonged-release system based on palygorskite and chitosan,
which are natural ingredients widely available, affordable, and accessible. The chosen model drug
was ethambutol (ETB), a tuberculostatic drug with high aqueous solubility and hygroscopicity, which
is incompatible with other drugs used in tuberculosis therapy. The composites loaded with ETB were
obtained using different proportions of palygorskite and chitosan through the spray drying technique.
The main physicochemical properties of the microparticles were determined using XRD, FTIR, thermal
analysis, and SEM. Additionally, the release profile and biocompatibility of the microparticles were
evaluated. As a result, the chitosan–palygorskite composites loaded with the model drug appeared
as spherical microparticles. The drug underwent amorphization within the microparticles, with
an encapsulation efficiency greater than 84%. Furthermore, the microparticles exhibited prolonged
release, particularly after the addition of palygorskite. They demonstrated biocompatibility in an
in vitro model, and their release profile was influenced by the proportion of inputs in the formulation.
Therefore, incorporating ETB into this system offers improved stability for the administered product
in the initial tuberculosis pharmacotherapy dose, minimizing its contact with other tuberculostatic
agents in the treatment, as well as reducing its hygroscopicityCoordenação de Aperfeiçoamento de Pessoal de
Nível Superior-Brazil (CAPES)—Process n 88887.131333/2016-00
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