472 research outputs found

    A multicriteria optimization framework for the definition of the spatial granularity of urban social media analytics

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    The spatial analysis of social media data has recently emerged as a significant source of knowledge for urban studies. Most of these analyses are based on an areal unit that is chosen without the support of clear criteria to ensure representativeness with regard to an observed phenomenon. Nonetheless, the results and conclusions that can be drawn from a social media analysis to a great extent depend on the areal unit chosen, since they are faced with the well-known Modifiable Areal Unit Problem. To address this problem, this article adopts a data-driven approach to determine the most suitable areal unit for the analysis of social media data. Our multicriteria optimization framework relies on the Pareto optimality to assess candidate areal units based on a set of user-defined criteria. We examine a case study that is used to investigate rainfall-related tweets and to determine the areal units that optimize spatial autocorrelation patterns through the combined use of indicators of global spatial autocorrelation and the variance of local spatial autocorrelation. The results show that the optimal areal units (30 km2 and 50 km2) provide more consistent spatial patterns than the other areal units and are thus likely to produce more reliable analytical results

    Isolation of Root Endophytic Bacteria in Elephant Grass (\u3cem\u3ePennisetum purpureum\u3c/em\u3e Schum.) Cultivars

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    Elephant grass (Pennisetum purpureum Schum.) is one of the most productive warm-season grasses. Farmers utilize elephant grass in different forms, such as cut-and-carry operations, grazing, conserved forage (silage, hay), and as an energy source (Lira et al. 2010). Nitrogen (N) is an essential element for plant growth and development and it is usually a limiting factor for forage production in the tropics (Boddey et al. 2004). Biological N fixation (BNF) may occur in warm-season grasses by their association with diazotrophic bacteria. These bacteria colonize different niches in the host plant. Endophytic bacteria form colonies inside the plant tissue whereas epiphytic bacteria colonize plant external surfaces (Compant et al. 2010). Both types of bacteria may benefit host plants (Badri et al. 2009). This study evaluated endophytic diazotrophic bacteria density associated to the roots of different elephant grass cultivars (cvs. ‘Elefante B’, ‘Venezuela’, and ‘Pioneiro’) using two N-free growth media, at different evaluation periods

    \u3cem\u3eIn Situ\u3c/em\u3e Digestibility of \u3cem\u3eGliricidia sepium\u3c/em\u3e Combined with \u3cem\u3eBrachiaria decumbens\u3c/em\u3e in a Silvopastoral System

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    Silvopastoral system (SPS) are characterized by a combination of trees, pasture and herbivores animals, in the same physical area, in order to obtain diversified products. A promising legume tree that has been studied and used in SPS in tropical areas is gliricidia [Gliricidia sepium (Jacq.) Steud]. Advantages of gliricidia use in SPS include N inputs via biological fixation, improvement of soil properties, nutrient cycling and also a source of feed to grazing animals (Cubillos-Hinojosa et al., 2011). Gliricidia has high crude protein concentration in its leaves, which complements the usual N-poor diet of ruminants grazing warm-season grasses. The introduction of gliricidia in SPS faces a problem due to the low initial acceptability by cattle, being necessary an adaptation period in order to cattle reach satisfactory intake levels (Carvalho Filho et al., 1997). In general, the quality of the forages can be predicted by accessing their nutritive value, represented by the chemical composition and digestibility of the forage constituents (Van Soest, 1994). The digestibility of dry matter in forages consumed in a SPS can be influenced by the forage species used, by grass/legume combinations, and by the proportion that each forage species takes in the diet of the ruminants. This study evaluated in situ digestibility of gliricidia in increasing levels of inclusion in the diet composed by sabi grass (Brachiaria decumbens, Stapf) in a silvopastoral system

    Brazilian guideline for the treatment of patients with opioids dependence syndrome

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    There is a relatively low prevalence of opioid use in Brazil, particularly involving the non-medical use of codeine and opiate-containing syrups. However, opioid dependence syndrome shows a significant total impact on mortality and morbidity. Over the past 20 years, scientific progress has changed our understanding of the nature of opioid addiction and its various possible treatments. Addiction is a chronic illness treatable if the treatment is well-delivered and tailored to the needs of the particular patient. There is indeed an array of treatments that can effectively reduce drug use, help manage drug cravings, prevent relapses and restore people to productive social functioning. The treatment of drug addiction will be part of long-term, medical, psychological, and social perspectives. This guideline aims at providing guidance to psychiatrists and other mental health professionals who care for patients with Opioid Dependence Syndrome. It comments on the somatic and psychosocial treatment that is used for such patients, and reviews scientific evidences and their strength. Also, the essential historical, epidemiological and neurobiological aspects of Opioid Dependence are reviewed.Existe uma prevalência relativamente baixa do uso de ópioides no Brasil, em particular envolvendo o uso não médico da codeína e de xaropes que contêm opióides. No entanto, a síndrome de dependência apresenta um significativo impacto total na mortalidade e morbidade. Nos últimos 20 anos, o avanço científico tem modificado nosso entendimento sobre a natureza da adição aos opióides e os variados tratamentos possíveis. A adição é uma doença crônica tratável se o tratamento for realizado e adaptado tendo em vista as necessidades do paciente específico. Há, de um fato, um conjunto de tratamentos que podem efetivamente reduzir o uso da droga, ajudar a gerenciar a fissura pela droga, prevenir recaídas e recuperar as pessoas para o funcionamento social produtivo. O tratamento da dependência de drogas será parte de perspectivas de longo prazo do ponto de vista médico, psicológico e social. Esta diretriz almeja fornecer um guia para os psiquiatras e outros profissionais de saúde que tratam de pacientes com Síndrome de Dependência de Opióides. Ela tece comentários sobre o tratamento somático e psicossocial que é utilizado nesses pacientes e revisa as evidências científicas e seu poder. Da mesma forma, os aspectos históricos, epidemiológicos e neurobiológicos da dependência de opióides são revisados.Universidade de São Paulo Hospital de Clínicas Instituto de PsiquiatriaFaculdade de Medicina do ABCJohns Hopkins University School of MedicineAssociação Brasileira de Psiquiatria Departamento de Dependência QuímicaHospital Albert EinsteinUniversidade Federal de São Paulo (UNIFESP)UNIADUNIFESPSciEL

    FTA-LAMP based biosensor for a rapid in-field detection of Globodera pallida—the pale potato cyst nematode

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    The combination of a sensitive and specific magnetoresistive sensing device with an easy DNA extraction method and a rapid isothermal amplification is presented here targeting the on-site detection of Globodera pallida, a potato endoparasitic nematode. FTA-cards were used for DNA extraction, LAMP was the method developed for DNA amplification and a nanoparticle functionalized magnetic-biosensor was used for the detection. The combinatorial effect of these three emerging technologies has the capacity to detect G. pallida with a detection limit of one juvenile, even when mixed with other related species. This combined system is far more interesting than what a single technology can provide. Magnetic biosensors can be combined with any DNA extraction protocol and LAMP forming a new solution to target G. pallida. The probe designed in this study consistently distinguished G. pallida (∆Vacbinding/Vacsensor above 1%) from other cyst nematodes (∆Vacbinding/Vacsensor below 1%). It was confirmed that DNA either extracted with FTA-cards or Lab extraction Kit was of enough quantity and quality to detect G. pallida whenever present (alone or in mixed samples), ensuring probe specificity and sensitivity. This work provides insights for a new strategy to construct advanced devices for pathogens in-field diagnostics. LAMP runs separately but can be easily integrated into a single device

    Social Networks Shape the Transmission Dynamics of Hepatitis C Virus

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    Hepatitis C virus (HCV) infects 170 million people worldwide, and is a major public health problem in Brazil, where over 1% of the population may be infected and where multiple viral genotypes co-circulate. Chronically infected individuals are both the source of transmission to others and are at risk for HCV-related diseases, such as liver cancer and cirrhosis. Before the adoption of anti-HCV control measures in blood banks, this virus was mainly transmitted via blood transfusion. Today, needle sharing among injecting drug users is the most common form of HCV transmission. Of particular importance is that HCV prevalence is growing in non-risk groups. Since there is no vaccine against HCV, it is important to determine the factors that control viral transmission in order to develop more efficient control measures. However, despite the health costs associated with HCV, the factors that determine the spread of virus at the epidemiological scale are often poorly understood. Here, we sequenced partial NS5b gene sequences sampled from blood samples collected from 591 patients in São Paulo state, Brazil. We show that different viral genotypes entered São Paulo at different times, grew at different rates, and are associated with different age groups and risk behaviors. In particular, subtype 1b is older and grew more slowly than subtypes 1a and 3a, and is associated with multiple age classes. In contrast, subtypes 1a and 3b are associated with younger people infected more recently, possibly with higher rates of sexual transmission. The transmission dynamics of HCV in São Paulo therefore vary by subtype and are determined by a combination of age, risk exposure and underlying social network. We conclude that social factors may play a key role in determining the rate and pattern of HCV spread, and should influence future intervention policies

    Forage Intake and Nitrogen Retention in Wethers Fed Ryegrass Haylage Supplemented with Maize Silage

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    Many decision support tools have been developed to predict herbage intake with herbivore ruminants indoors (Faverdin 1992) or at grazing, both using short-term (Baumont et al. 2004) or daily scale input variables (Heard et al. 2004; Delagarde et al. 2011). However, the ingestive and digestive interactions when diets with more than one type of forage are used have not been sufficiently studied. The aim of this study was to assess the effects of maize silage supplementation to wethers receiving ryegrass haylage on OM intake, OM digestibility, microbial protein synthesis and N retention

    Isolation, absolute configuration and cytotoxic activities of alkaloids from Hippeastrum goianum (Ravenna) Meerow (Amaryllidaceae)

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    The phytochemical study of Hippeastrum goianum led to the identification of 13 compounds by means of gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR). Compounds 7-demethoxy-9-O-methylhostasine (1) and 7-deoxi-trans-dihydronarciclasine (2) had their absolute configurations determined by vibrational circular dichroism (VCD). This is the first time that compound 1 is described in the Amaryllidaceae family. The cytotoxicity of all isolated compounds was tested against colorectal carcinoma (HCT 116), breast carcinoma (MCF-7), and non-tumor human retinal pigment epithelium (RPE) cell lines. The half-maximum inhibitory concentration (IC50) of compound 2 against each cell line was equivalent to the positive control (doxorubicin), indicating a considerable cytotoxic activity. Keywords: narciclasine; galasine; cytotoxic activity; absolute configuration; vibrational circular dichrois

    Revisão sistemática sobre nanopartículas carreadoras de fármacos: lipossomos, uma ferramenta em ascensão no tratamento do câncer de mama / Systematic review on drug carrier nanoparticles: liposomes, an ascending tool in the treatment of breast cancer

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    A presente pesquisa objetiva descrever os benefícios da utilização dos lipossomas no tratamento do câncer de mama. Trata-se de uma revisão integrativa da literatura, qualitativa/qualitativa, realizada entre os meses de janeiro a Abril 2021, nas bases de dados da Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Literatura Internacional em Ciências da Saúde (PUBMED), na Biblioteca Eletrônica Científica Online (Scielo) e PUBMED/MEDLINE dados bibliográficos da Biblioteca Nacional de Medicina dos Estados Unidos da América. As pesquisas nas fontes acima possibilitarão a busca por estudos publicados no cenário nacional e internacional, a partir da inclusão de artigos científicos disponíveis na íntegra, em livre acesso, publicados no período entre 2016 a 2020. Os idiomas pesquisados são português, inglês e espanhol. O interesse são aqueles aqueles que, após leitura do título e resumo, abordassem aspectos relacionados à temática do estudo, demonstrando a atuação dos lipossomas na diminuição do processo cancerígeno das mamas. Foram selecionados 21 artigos para subsidiar a revisão de literatura. Destacou-se nesse estudo, a importância do uso da nanotecnologia para o tratamento eficaz dos diferentes tipos de câncer e nesse contexto os lipossomas podem desenvolver a função de transportar distintos fármacos até a área afetada pelo tumor do câncer de mama. Esse tipo de tratamento, aliado ao diagnóstico precoce, demonstra enorme potencial de eficácia na erradicação tumoral, minimizando risco e efeitos adversos com benefícios efetivos aos pacientes em tratamentos
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