3,312 research outputs found

    Apología de la pena en dos visiones reduccionistas de la cuestión criminal en Argentina

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    Fil: Cid Ferreira, Lucia. Universidad Nacional de Tucumán. Facultad de Derecho y Ciencias Sociales. Centro de Investigaciones Sociológicas

    Bayesian Comparison of Interacting Scenarios

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    We perform a Bayesian model selection analysis for different classes of phenomenological coupled scenarios of dark matter and dark energy with linear and non-linear interacting terms. We use a combination of some of the latest cosmological data such as type Ia supernovae (SNe Ia), cosmic chronometers (CC), cosmic microwave background (CMB) and two sets of baryon acoustic oscillations measurements, namely, 2-dimensional angular measurements (BAO2) and 3-dimensional angle-averaged measurements (BAO3). We find weak and moderate evidence against two-thirds of the interacting scenarios considered with respect to Λ\LambdaCDM when the full joint analysis is considered. About one-third of the models provide a description to the data as good as the one provided by the standard model. Our results also indicate that either SNe Ia, CC or BAO2 data by themselves are not able to distinguish among interacting models or Λ\LambdaCDM but the standard BAO3 measurements and the combination with the CMB data are indeed able to discriminate among them. We find that evidence disfavoring interacting models is weaker when we use BAO2 (data claimed to be almost model-independent) instead of the standard BAO3 measurements. These results help select classes of viable and non-viable interacting models in light of current data.Comment: 32 page

    3 - Contrats en immobilisation

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    Densidade básica (g.cm-3: peso seco / volume úmido) da madeira foi determinada para 13 das principais espécies arbóreo-arbustivas de um ecossistema de "campina" (caatinga amazônica) situado em Roraima, extremo norte da Amazônia brasileira. As amostras de madeira para o cálculo da densidade básica de cada espécie foram compostas por "discos amostrais" (casca, alburno e cerne) de diferentes classes diamétricas. No total, foram amostrados 98 indivíduos, perfazendo 150 peças de madeira (52 com diâmetro 4,8cm). A espécie de maior densidade média foi Matayba arborescens (Aubl.) Radlk. (0,68 g.cm-3), seguida de Humiria balsamifera (Aubl.) St. Hill. (0,67 g.cm-3) e Pera schomburgkiana Müel. Arg. (0,64 g.cm-3). As classes de menor diâmetro foram também as de menor valor absoluto: 0,59 ± 0,06 (DP) g.cm-3 ( 4,8cm). A média ponderada pela biomassa do ecossistema foi de 0,64 ± 0,08 g.cm-3. Este resultado é 15,2% inferior ao comumente utilizado para transformação de volume de madeira em biomassa para ecossistemas de "campina" na Amazônia, influenciando diretamente nos cálculos de emissão de gases do efeito estufa.Wood density (g.cm-3: oven-dry weight / wet volume) was determined for 13 of the main tree species of a "campina" ecosystem (Amazon caatinga) located in Roraima, north portion of Brazilian Amazonia. The wood samples for calculation of the density of each species were "sample disks" (bark, sapwood and heartwood) of different diameter classes. In total, 98 individuals were sampled in 150 wood pieces (52 with diameter 4.8cm). The species with the highest wood density was Matayba arborescens (Aubl.) Radlk. (0.68 g.cm-3), followed by Humiria balsamifera (Aubl.) St. Hill. (0.67 g.cm-3) and Pera schomburgkiana Müel. Arg. (0.64 g.cm-3). The smaller diameter classes were also those with lower density: 0.59 ± 0.06 (SD) g.cm-3 ( 4.8cm). The weighted mean by biomass of the ecosystem was 0.64 ± 0.08 g.cm-3. This result is lower by 15.2% than that presently used for transformation of wood volume in biomass for "campina" ecosystems in Amazonia, influencing directly in the calculations of greenhouse gas emissions

    Algebraic Cryptanalysis and RFID Authentication

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    Apología en la pena en dos visiones reduccionistas de la cuestión criminal en Argentina

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    Con la perspectiva de la sociología y de la criminología crítica, este trabajo pretende realizar una exposición y una crítica de ambas visiones de la cuestión criminal, apuntando los problemas teóricos y prácticos que implican.Facultad de Humanidades y Ciencias de la Educació

    Galhadores (Cecidomyiidae, Diptera) em Calophyllum brasiliense (Clusiaceae): descrições e biologia

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    Five new species of gall makers (Cecidomyiidae, Diptera) associated with Calophyllum brasiliense (Clusiaceae) are described and illustrated from Carapebus, State of Rio de Janeiro, Brazil : Lopesia caulinaris, L.conspicua, L. elliptica, L. linearis and Contarinia gemmae. Some biological and ecological data are given.Cinco espécies novas galhadoras (Cecidomyiidae, Diptera) associadas com Calophyllum brasiliense (Clusiaceae) são descritas e ilustradas de Carapebus, Estado do Rio de Janeiro, Brasil: Lopesia caulinaris, L. conspicua, L. elliptica, L. linearis and Contarinia gemmae. Algumas informações biológicas e ecológicas são fornecidas

    Análise comparativa de vegetação lenhosa do ecossistema campina na Amazônia brasileira

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    Amazonian campinas are sclerophytic vegetation occurring in white sand soils. Although in the beginning they were just mentioned for the rio Negro basin, it is now know that the campinas are widely distributed in the Amazon and some other areas of Tropical America. Amazonian campinas occur as enclaves in areas with dominated by other vegetation types such as rain forests, savannas or campinarana forests. The sandy soils colonized by campinarana plants could be of different origins, such as: a) beds of ancient bodies of water that dry ; b) the sandy profiles derived from the erosion of sandstones from the Guiana Shield or the Brazilian Shield, and; c) ancient sand dunes of eolian origin. This present thesis is aiming to describe and compare from the floristic and phytosociologic point of view, nine Amazonian campinas. Only arboreal and shrubby species with diameter at breast height (DAP) > 5 cm were studied. The nine campinas studied contained, 252 species belonging to 121 genera and 44 families. The families of greatest floristic abundance were Fabaceae, Mytaceae, Rubiaceae, Clusiaceae, Malpighiaceae, and Annonaceae. The genera of most importance were Clusia, Emmotum, Pagamea, Tapirira, Eugenia, Matayba, Myrcia and Ouratea. The nine sampled areas exibited a high proportion of unique species: 72.6% of the species were just registered in one of the campinas. The high proportion of exclusive species resulted in a great floristic comparative distance among the campinas (Jaccard distance ranging from 0.471 to 0.942). In contrast, seven species (2.8% of total) occurred in more than five campinas. These species have wide neotropical distribution and occur in different physiognomies: Humiria balsamifera Aubl., Emmotum nitens Miers, Pagamea guianensis Aubl., Tapirira guianensis Aubl., Byrsonima crassifolia (L.) Kunth., Ouratea spruceana Engl. e Alchornea discolor Poepp. The analysis of the species distribution together with the floristic similarity and MDS analysis have found some phytogeographic patterns for the Amazonian campinas, such as: a) great floristic afinity among Amazonian campinas and the Guiana Shield vegetation and Venezuela-Colombia Llanos; b) campinas in contact with Amazon basin and Brazilian Shield, like the Serra do Cachimbo ones, show greater influence from the Cerrado vegetation; c) campinas from eastern Amazon has shown greater influence from the Guiana and Brazilian Shield floras; d) Low afinity between the Amazonian campinas and restinga vegetation from the Atlantic cost; e) Amazonian campinas from the Brazilian western extreme, like Cruzeiro do Sul (Acre), are significantly different from the other ones. The results of this work reinforce the need of biodiversity conservation programs for the Amazonian campinas due to the great floristic divergence observed among them, large endemic potential and its occurrence on restricted isolated spots.As campinas amazônicas são formações vegetais esclerófilas que se desenvolvem em solos de areia branca. Apesar de inicialmente citadas apenas para a bacia do Rio Negro, sabe-se atualmente que as campinas estão amplamente distribuídas na Amazônia e em outras áreas da América Tropical. As campinas ocorrem como enclaves em áreas com matriz de floresta ombrófila, cerrado ou campinarana. Os substratos arenosos colonizados pelas plantas de campina podem ser de diferente natureza, tais como: (a) leitos de antigos corpos de água que secaram, (b) perfis arenosos oriundos da decomposição de arenitos do Escudo Guianense e do Escudo Brasileiro, e (c) antigas dunas arenosas de origem heólica. O presente trabalho teve como objetivo descrever e comparar, do ponto de vista florístico e fitossociológico, nove campinas na Amazônia Brasileira. Foram estudadas apenas as espécies arbóreas e arbustivas com diâmetro na altura do peito (DAP) 5 cm. Foram registradas, nas nove campinas estudadas, 252 espécies pertencentes a 121 gêneros e 44 famílias. As famílias de maior riqueza florística foram Fabaceae, Myrtaceae, Rubiaceae, Clusiaceae, Malpighiaceae e Annonaceae. Os gêneros de maior importância foram Clusia, Emmotum, Pagamea, Tapirira, Eugenia, Matayba, Myrcia e Ouratea. As nove campinas amostradas exibiram uma alta proporção de espécies exclusivas: 72,6% das espécies foi registrada apenas em uma das campinas. A alta proporção de espécies exclusivas resultou em grande distância florística entre as campinas estudadas (distância de Jaccard variando de 0,471 a 0,942). Em contraste, sete espécies (2,8% do total) ocorreram em mais de cinco campinas. Estas espécies, de ampla distribuição neotropical e de ocorrência em diferentes fisionomias, são: Humiria balsamifera Aubl., Emmotum nitens Miers, Pagamea guianensis Aubl., Tapirira guianensis Aubl., Byrsonima crassifolia (L.) Kunth., Ouratea spruceana Engl. e Alchornea discolor Poepp. A análise de distribuição das espécies, juntamente com análises de similaridade florística e de ordenamento MDS (Escalonamento multi-dimensional não-métrico) indicam alguns padrões fitogeográficos para as campinas, tais quais: (a) grande afinidade florística entre as campinas amazônicas e a vegetação do Escudo Guianense e dos Llanos Venezuelanos/Colombianos; (b) campinas no contato da bacia amazônica com o Escudo Brasileiro – como as da Serra do Cachimbo - apresentam maior influência da vegetação do cerrado; (c) campinas do leste amazônico apresentam influência mista das floras do Escudo Guianense e do Escudo Brasileiro; (d) baixa afinidade da flora das campinas com a da Restinga Atlântica; (e) campinas do extremo oeste da Amazônia brasileira – como a de Cruzeiro do Sul (Acre) - são altamente diferenciadas das demais. Os resultados aqui apresentados reforçam a necessidade de programas de conservação da biodiversidade das campinas amazônicos, dada a alta diferenciação florística observada entre elas, a grande concentração de endemismos e sua ocorrência em manchas restritas e isoladas

    Effective immunization scenarios by vaccination against COVID-19 obtained through Bayesian analysis

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    The COVID-19 pandemic caused a health crisis on an unprecedented scale, due to the unstoppable spread of the disease through the global integration provided by the current strongly globalized society. Isolation policies recommended by WHO impacted countries economies, making it necessary to implement a range of economic, health, social and economic security policies, such as: financial aid packages for the population and companies, investment of resources for the structuring of hospital beds for the treatment of patients, implementation of population testing programs, among others. The impact of the pandemic proved to be quite significant especially for the so-called "developing countries", due to the difficulties in establishing the aforementioned range of security policies as well as mass testing of the population in order to reliably map the disease spreading. The implementation of those measure were limited not only by economic reasons, but also by political impediments. In the present study, a Bayesian analysis of the immunization rate against COVID-19 through vaccination, evaluating the immunization scenarios lasting or temporary. The logistics required for the vaccination campaign in Brazil were assessed by considering uncertainties in determining the daily rate of immunization, as well as the effectiveness of the vaccine made available for the population. In this intent, an epidemiological model was used compartmentalized, calibrated against historical data using the CATMIP stochastic algorithm. The obtained results indicate that the daily vaccination rate is the most important parameter of a successful immunization program, given an effectiveness rate equal or superior to 50%. However, a massive immunization rate needs to be conjugated with a responsible relaxing of the social distancing measures after the vaccination program start, under the risk of compromising any positive result in terms of the number of contaminated and deceased individuals

    Toxicity Evaluation of Quantum Dots (ZnS and CdS) Singly and Combined in Zebrafish (Danio rerio)

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    This work was supported by the Applied Molecular Biosciences Unit- UCIBIO which is financed by national funds from FCT/MCTES (UID/Multi/04378/2019) and by the Associate Laboratory for Green Chemistry- LAQV which is financed by national funds from FCT/MCTES (UID/QUI/50006/2019) and by the Marine and Environmental Sciences Centre (MARE) which is financed by national funds from FCT/MCTES (UID/MAR/04292/2019).The exponential growth of nanotechnology has led to the production of large quantities of nanomaterials for numerous industrial, technological, agricultural, environmental, food and many other applications. However, this huge production has raised growing concerns about the adverse effects that the release of these nanomaterials may have on the environment and on living organisms. Regarding the effects of QDs on aquatic organisms, existing data is scarce and often contradictory. Thus, more information is needed to understand the mechanisms associated with the potential toxicity of these nanomaterials in the aquatic environment. The toxicity of QDs (ZnS and CdS) was evaluated in the freshwater fish Danio rerio. The fishes were exposed for seven days to different concentrations of QDs (10, 100 and 1000 µg/L) individually and combined. Oxidative stress enzymes (catalase, superoxide dismutase and glutathione S-transferase), lipid peroxidation, HSP70 and total ubiquitin were assessed. In general, results suggest low to moderate toxicity as shown by the increase in catalase activity and lipid peroxidation levels. The QDs (ZnS and CdS) appear to cause more adverse effects singly than when tested combined. However, LPO results suggest that exposure to CdS singly caused more oxidative stress in zebrafish than ZnS or when the two QDs were tested combined. Levels of Zn and Cd measured in fish tissues indicate that both elements were bioaccumulated by fish and the concentrations increased in tissues according to the concentrations tested. The increase in HSP70 measured in fish exposed to 100 µg ZnS-QDs/L may be associated with high levels of Zn determined in fish tissues. No significant changes were detected for total ubiquitin. More experiments should be performed to fully understand the effects of QDs exposure to aquatic biota.publishersversionpublishe
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