6,157 research outputs found

    Mining archaeology sites at the Alto Minho region (Northern Portugal) - a management perspective

    Get PDF
    [Abstract] Archaeological mining sites in northern Portugal include a few roman gold mines in shear zones and the tin and tungsten mining of the first half of the XX century, widespread through the entire Alto Minho region, and related to residual-granite mineralization. Pre-roman vestiges of mineral resources disposal are restricted to Pleistocene industries, without known mining evidences. Better preserved sites represent the tin and tungsten period from which, some testimony of local peculiar technologies, are remaining. From a land use point of view, the preservation of old excavations and ruined plants may be in equilibrium with new mining projects for the mineral resources potential and new forms of tourism regional offe

    Spin-orbit mode transfer via a classical analog of quantum teleportation

    Full text link
    We translate the quantum teleportation protocol into a sequence of coherent operations involving three degrees of freedom of a classical laser beam. The protocol, which we demonstrate experimentally, transfers the polarisation state of the input beam to the transverse mode of the output beam. The role of quantum entanglement is played by a non-separable mode describing the path and transverse degrees of freedom. Our protocol illustrates the possibility of new optical applications based on this intriguing classical analogue of quantum entanglement.Comment: 5 pages, 7 figure

    Respiratory hospital admission risk near large composting facilities

    Get PDF
    AbstractBackgroundLarge-scale composting can release bioaerosols in elevated quantities, but there are few studies of health effects on nearby communities.MethodsA cross-sectional ecological small area design was used to examine risk of respiratory hospital admissions within 2500m of all 148 English large-scale composting facilities in 2008–10. Statistical analyses used a random intercept Poisson regression model at Census Output Area (COA) level (mean population 310). Models were adjusted for age, sex, deprivation and tobacco sales.ResultsAnalysing 34,963 respiratory hospital admissions in 4656 COAs within 250–2500m of a site, there were no significant trends using pre-defined distance bands of >250–750m, >750–1500m and >1500–2500m. Using a continuous measure of distance, there was a small non-statistically significant (p=0.054) association with total respiratory admissions corresponding to a 1.5% (95% CI: 0.0–2.9%) decrease in risk if moving from 251m to 501m. There were no significant associations for subgroups of respiratory infections, asthma or chronic obstructive pulmonary disease.ConclusionThis national study does not provide evidence for increased risks of respiratory hospital admissions in those living beyond 250m of an outdoor composting area perimeter. Further work using better measures of exposure and exploring associations with symptoms and disease prevalence, especially in vulnerable groups, is recommended to support regulatory approaches

    Slip behavior in liquid films on surfaces of patterned wettability: Comparison between continuum and molecular dynamics simulations

    Get PDF
    We investigate the behavior of the slip length in Newtonian liquids subject to planar shear bounded by substrates with mixed boundary conditions. The upper wall, consisting of a homogenous surface of finite or vanishing slip, moves at a constant speed parallel to a lower stationary wall, whose surface is patterned with an array of stripes representing alternating regions of no-shear and finite or no-slip. Velocity fields and effective slip lengths are computed both from molecular dynamics (MD) simulations and solution of the Stokes equation for flow configurations either parallel or perpendicular to the stripes. Excellent agreement between the hydrodynamic and MD results is obtained when the normalized width of the slip regions, a/σO(10)a/\sigma \gtrsim {\cal O}(10), where σ\sigma is the (fluid) molecular diameter characterizing the Lennard-Jones interaction. In this regime, the effective slip length increases monotonically with a/σa/\sigma to a saturation value. For a/σO(10)a/\sigma \lesssim {\cal O}(10) and transverse flow configurations, the non-uniform interaction potential at the lower wall constitutes a rough surface whose molecular scale corrugations strongly reduce the effective slip length below the hydrodynamic results. The translational symmetry for longitudinal flow eliminates the influence of molecular scale roughness; however, the reduced molecular ordering above the wetting regions of finite slip for small values of a/σa/\sigma increases the value of the effective slip length far above the hydrodynamic predictions. The strong inverse correlation between the effective slip length and the liquid structure factor representative of the first fluid layer near the patterned wall illustrates the influence of molecular ordering effects on slip in non-inertial flows.Comment: 12 pages, 10 figures Web reference added for animations: http://www.egr.msu.edu/~priezjev/bubble/bubble.htm

    Competição de cultivares de arroz de sequeiro em diferentes épocas de plantio em Rondônia.

    Get PDF
    Procura identificar plantios em diferentes epocas, cultivares mais produtivas e melhor adaptaveis. Os experimentos foram conduzidos nas bases fisicas de Porto Velho e Ouro Preto-RO. Utilizou-se delineamento de bloco casualisado, com tres repeticoes. Foram utizadas dez cultivares: IAC-25, IAC-47, IAC-5100, IAC-5544, Chatao, Bico Ganga, IAC-1131, IAC-1246, Pratao precoce e A-19, provenientes da EMBRAPA-CNPAF. Fez-se necessario substituir a cultivar Agulhinha, EEA-409, Dawn, IR-665,14.3.5, P-723-6.3.1 e Cica-4 usadas no ano anterior, pelas seis primeiras das acima citadas, decorrentes do comportamento insatisfatorio para as condicoes locais. Constatou-se a presenca de brusone (Pyricularia orizae Cav.), com baixa incidencia, nas cuiltivares de IAC-25, IAC-5100,IAC-5544, Bico ganga, Pratao precoce e A-19. Concluiu-se que em Ouro Preto as cultivares que se destacaram foram IAC-47, Bico ganga, IAC-1246 e a cultivar que menos acamou foi IAC-47. Observou-se que a partir da segunda quinzena de out., o acamamento diminui, havendo porem uma inluencia negativa na producao.bitstream/item/58759/1/COT-1130-0001.pd

    Avaliação de cultivares de milho no Território Federal de Rondônia.

    Get PDF
    Procurou-se identificar melhores cultivares de milho para uso imediato dos agricultores. Os experimentos foram instalados em Ouro Preto, RO, no periodo de 1977/78, com dois ensaios, sendo um de milho normal e outro braquitico. O solo foi do tipo Podzolico Vermelho Amarelo distrofico. Foi feita adubacao mineral de NPK, 60-60-60. Resultados demonstram que as melhores cultivares de milho normal foram: Composto Dentado, Centralmex, Poza Rica e Yousafwala 7428 e Composto A; Milho braquitico: Composto Dentado Brachitico, Piranao e Composto Dentado Braquitico x Composto Flint Braquitico.bitstream/item/46846/1/COT-8-19790001.pd

    Fuzzy logic as a decision-making support system for the indication of bariatric surgery based on an index (OBESINDEX) generated by the association between body fat and body mass index

    Get PDF
    Background: A Fuzzy Obesity Index (OBESINDEX) for use as an alternative in bariatric surgery indication (BSI) is presented. The search for a more accurate method to evaluate obesity and to indicate a better treatment is important in the world health context. BMI (body mass index) is considered the main criteria for obesity treatment and BSI. Nevertheless, the fat excess related to the percentage of Body Fat (%BF) is actually the principal harmful factor in obesity disease that is usually neglected. This paper presents a new fuzzy mechanism for evaluating obesity by associating BMI with %BF that yields a fuzzy obesity index for obesity evaluation and treatment and allows building up a Fuzzy Decision Support System (FDSS) for BSI.

Methods: Seventy-two patients were evaluated for both BMI and %BF. These data are modified and treated as fuzzy sets. Afterwards, the BMI and %BF classes are aggregated yielding a new index (OBESINDEX) for input linguistic variable are considered the BMI and %BF, and as output linguistic variable is employed the OBESINDEX, an obesity classification with entirely new classes of obesity in the fuzzy context as well is used for BSI.

Results: There is a gradual, smooth obesity classification and BSI when using the proposed fuzzy obesity index when compared with other traditional methods for dealing with obesity.

Conclusion: The BMI is not adequate for surgical indication in all the conditions and fuzzy logic becomes an alternative for decision making in bariatric surgery indication based on the OBESINDEX

    Banco de sementes em sistemas de produção de agricultura com queima e sem queima no município de Marapanim, Pará.

    Get PDF
    Na agricultura de corte e queima, a capoeira tem como papel principal a fertilização da terra após a queima de sua biomassa vegetal. Geralmente as repetidas queimadas acabam destruindo todas as formas de regeneração, incluindo o banco de sementes. Pensando nessa problemática, o Projeto Studies of Human Impact on Forests and Floodplains in the Tropics (SHIFT), no qual esta pesquisa se insere, após uma série de estudos básicos sobre as capoeiras da região Bragantina, vem desenvolvendo uma alternativa de produção agrícola em que a capoeira é usada como fonte de nutrientes e matéria orgânica para o solo em sistemas de produção de ?agricultura sem queima?. O trabalho desenvolvido no município de Marapanim foi um experimento participativo, uma nova abordagem do projeto, onde as áreas foram definidas pelos agricultores. O objetivo do trabalho foi avaliar o potencial do banco de sementes de áreas submetidas a diferentes práticas agrícolas, caracterizando qualitativa e quantitativamente sua composição florística. Foram testadas as hipóteses de que o fogo diminui o potencial do banco de sementes e cria condições favoráveis à regeneração de espécies invasoras herbáceas. A cobertura triturada minimiza os impactos provocados pela queima sobre a diversidade vegetal e aumenta a regeneração de espécies acumuladoras de biomassa. O potencial de germinação do banco de sementes nos tratamentos foi monitorado durante 270 dias. Nos tratamentos queima e cobertura triturada, foram avaliadas a densidade, riqueza de espécies, famílias e formas de vida predominantes. No banco de sementes antes do manejo do solo, a densidade média na queima foi de 284 indivíduos/m2 e na cobertura triturada 328 indivíduos/m2. Depois do manejo do solo na queima, foram encontrados em média 23 indivíduos/m2 e na cobertura triturada 139 indivíduos/m2. As espécies mais freqüentes nos dois momentos e nos dois tratamentos foram Borreria latifolia, Fimbristylis meliacea e Cyperus diffusus. As famílias Cyperaceae, Rubiaceae e Poaceae apareceram em alta frequência em todas as áreas e nos dois tratamentos. Além dessas, destacaram-se as famílias Euphorbiaceae, Melastomataceae, Malvaceae, Lamiaceae, Scrophulariaceae e Asteraceae. As formas de vida mais comuns encontradas nos tratamentos foram as ervas. Os diferentes tratamentos afetaram a abundância e riqueza florística, diminuindo o número de sementes de espécies arbóreas e arbustivas, acumuladoras de biomassa
    corecore