603 research outputs found

    Клан як квазі-інститут політичних систем близькосхідних країн

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    Розглянуто клан як специфічний фактор близькосхідного політичного процесу, проаналізовано його характерні особливості, а також подібності і відмінності з інститутами політичної системи плюральної демократії, такими як первинна соціалізаційна група, політична партія, неурядова організація.Clan as special actor of Middle Eastern political processis considered. Its specialties are analysed and similarities and differences with such institutes of plural democracy political system as first socialization group, NGO, political party are defined

    Crafting a Systematic Literature Review on Open-Source Platforms

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    This working paper unveils the crafting of a systematic literature review on open-source platforms. The high-competitive mobile devices market, where several players such as Apple, Google, Nokia and Microsoft run a platforms- war with constant shifts in their technological strategies, is gaining increasing attention from scholars. It matters, then, to review previous literature on past platforms-wars, such as the ones from the PC and game-console industries, and assess its implications to the current mobile devices platforms-war. The paper starts by justifying the purpose and rationale behind this literature review on open-source platforms. The concepts of open-source software and computer-based platforms were then discussed both individually and in unison, in order to clarify the core-concept of 'open-source platform' that guides this literature review. The detailed design of the employed methodological strategy is then presented as the central part of this paper. The paper concludes with preliminary findings organizing previous literature on open-source platforms for the purpose of guiding future research in this area.Comment: As presented in 10th IFIP WG 2.13 International Conference on Open Source Systems, OSS 2014, San Jos\'e, Costa Rica, May 6-9, 201

    Bone Mineral Density in Healthy Female Adolescents According to Age, Bone Age and Pubertal Breast Stage

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    This study was designed to evaluate bone mineral density (BMD) in healthy female Brazilian adolescents in five groups looking at chronological age, bone age, and pubertal breast stage, and determining BMD behavior for each classification. Seventy-two healthy female adolescents aged between 10 to 20 incomplete years were divided into five groups and evaluated for calcium intake, weight, height, body mass index (BMI), pubertal breast stage, bone age, and BMD. Bone mass was measured by bone densitometry (DXA) in lumbar spine and proximal femur regions, and the total body. BMI was estimated by Quetelet index. Breast development was assessed by Tanner's criteria and skeletal maturity by bone age. BMD comparison according to chronologic and bone age, and breast development were analyzed by Anova, with Scheffe's test used to find significant differences between groups at P≤0.05. BMD (g·cm(-2)) increased in all studied regions as age advanced, indicating differences from the ages of 13 to 14 years. This group differed to the 10 and 11 to 12 years old groups for lumbar spine BMD (0.865±0.127 vs 0.672±0.082 and 0.689±0.083, respectively) and in girls at pubertal development stage B3, lumbar spine BMD differed from B5 (0.709±0.073 vs 0.936±0.130) and whole body BMD differed from B4 and B5 (0.867±0.056 vs 0.977±0.086 and 1.040±0.080, respectively). Bone mineralization increased in the B3 breast maturity group, and the critical years for bone mass acquisition were between 13 and 14 years of age for all sites evaluated by densitometry

    Utilização da equação de Hargreaves Samani para o cálculo da ETo em estufas

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    PosterA equação de Hargreaves Samani, HS, tem sido utilizada com sucesso para o cálculo da Evapotranspiração, Eto, ao ar livre. Os resultados indicam uma boa correlação entre a Eto obtida por este método e a obtida pelo método de Penman-Monteith, PM, que exige um conjunto maior de parâmetros. Até a data pouco se sabe sobre a aplicabilidade da equação de HS em agricultura protegida. Neste ensaio foram instalados minilisimetros numa estufa na Herdade de Mitra, Évora. A cultura utilizada foi a relva, por forma a eliminar a necessidade de determinação exacta do coeficiente cultural. Foram medidos em intervalos de 15 minutos a Temperatura do ar, radiação, Humidade Relativa e o vento no interior e exterior da estufa. A equação de HS foi calibrada com base nos valores dos lisimetros e com base na equação de PM. Os resultados indicam que no interior da estufa há uma diminuição da radiação em 44%, e o aumento da temperatura máxima em 2,4ºC e da temperatura mínima em 3,7ºC. A utilização da estufa permitiu uma poupança de água de 42% A equação de HS resulta em boas estimativas de Eto, desde que seja devidamente calibrada para a radiação no interior da estufa. A inclusão da radiação no cálculo da Eto pela equação de HS não melhora os resultados--------------------------ABSTRACT----The Hargreaves Samani equation, HS, has been used successfully for calculating Evapotranspiration, Eto, in open air. The results indicate a good correlation between Eto obtained with this method and that obtained through the Penman- Monteith, PM, method, which requires a larger number of parameters. Until now, little is known about the use of the HS equation in greenhouses. In this work, mini-lysimeters were installed in a greenhouse at the Mitra Experimental Farm, in Évora. Lawn was used as the crop, in order to eliminate the need for the exact determination of the crop coefficient. Air temperature, radiation, relative humidity and wind were measured at 15 minute intervals inside and outside of the greenhouse. The HS equation was calibrated based on the values from the lysimeters and the PM equation. The results indicate that inside the greenhouse the radiation decreases by 44%, maximum temperature increases by 2.4ºC and the minimum temperature by 3,7ºC. The use of greenhouse resulted in a water saving of 42%. The HS equation results in good estimates of Eto once it has been calibrated for the radiation intensity inside the greenhouse. The inclusion of the radiation in the calculation of Eto by the HS equation did not improve the results

    STRUCTURAL AND PHOTOLUMINESCENCE PROPERTIES OF THE (Ni,Zn) Fe2O4-BaTiO3 MULTIFERROIC COMPOSITE NANOPOWDERS

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    Ferroics and multiferroics are among the most attractive multifunctional materials. In recent years, multiferroic composite consisted of two or more ferroic orders, such as ferroelectric, ferromagnetic, or ferroelastic, in which coupling between these phases can produce magnetoelectric effect, has been drawing significant attention. Besides others, (Ni, Zn)Fe2O4-BaTiO3 composites have attracted considerable attention not only due to fundamental research of magneto-electric effect, but also for the potential applications in many electronic devices such as drug delivery, heterogeneous catalysis, levitated railway system, magnetic-refrigeration, microwave devices, antennas, memory devices, etc. In this composite, (Ni,Zn)Fe2O4(NZF) possesses magnetic behavior, and the ferroelectricity is due to the presence of BaTiO3 (BT). In the present work, it was investigated the structural and photoluminiscence properties of NZF-BT composite nanopowders prepared by auto-combution method and the different ratio of NZF/BT was explored. XRD indicated well cristallized powders but with small presence of secondary phases respecting to BT. By FE-SEM analyses was noticed the agglomerates with wide particles size distribution, as well as the difference of the particles morphology between (Ni,Zn)Fe2O4 and BaTiO3. FT-IR spectra display interactions between metal-oxygen around 500-600 cm-1. The different ratio of NZF/BT effects on the optical band gap values indicating the formation of intermediary levels modifying the Fermi level. Photoluminescence (PL) analysis provides important information about the materials structures, however the PL behavior of these composites is not very well known. The presence of PL emission suggests that the structures of the materials are medium range disordered. All samples showed a broad band emission centered around 450 nm, being a region characteristic of resultant emission from the presence of shallow defects in materials structures. This behavior is reinforced by deconvolution of PL bands, which shows the contribution of tree sub bands to emission (blue, green and yellow emission), being that the largest area of spectra is occupied by a band correspondent to blue emission

    BiFeO3 THIN FILMS: INFLUENCE OF DOPING ON STRUCTURE AND PROPRETIES

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    Thin films of BiFeO3 and doped BiFeO3 were prepared by chemical solution deposition method. Because of low electrical resistivity of BiFeO3 which often prevents it to exhibit ferroelectric properties, several elements were used as dopants, partially replacing Bi3+ (Y3+, Sr2+) or Fe3+ (Ti4+, Zr4+) ions. Dopants may also reduce the size of the grains improving the magnetic properties. Pure BiFeO3 phase was formed for all compositions without preferred orientation. All films are around 300 nm thick, with relatively densely packed round grains of the size well below 100 nm as it is presented with micrographies in Fig. 1. Some of the dopants have lowered the size of the grains and increased electrical resistivity enough for ferroelectric hysteresis to be measured at fields above 100 kV/c

    Células solares ultrafinas de Cu (In,Ga)Se2 : passivação de interfaces

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    CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMO: A comunidade de Cu(In,Ga)Se2 (CIGS) tem focado grande parte da sua investigação no estudo e melhoramento das propriedades cristalinas do CIGS.A última estratégia utilizada, que tem permitido aumentar o valor de eficiência das células solares, passa pela implementação de elementos alcalinos através de tratamentos pós-deposição (PDT). Para se atingir valores de conversão de eficiência competitivos é necessário melhorar as interfaces do CIGS. Neste estudo, focamo-nos no estudo das propriedades morfológicas, estruturais e optoelectrónicas entre o CIGS e a alumina (Al2O3), que tem o potencial de ser usada como camada passivadora frontal. Pode-se concluir que as propriedades morfológicas e estruturais não são alteradas devido à deposição do Al2O3. O Al2O3 não resiste ao banho químico usado para a deposição do CdS. O Al2O3 apresenta um valor de densidade de defeitos baixos, uma propriedade desejada destas camadas. Este estudo demonstra a potencialidade de se utilizar a Al2O3, para camadas buffer alternativas, que não usem processos químicos durante a sua deposição.ABSTRACT: Cu(In,Ga)Se2 (CIGS) community have been focusing the research line in the study and improvement of the crystalline properties of CIGS. The last trend, to increase the light to power conversion efficiency values, is the use of fluoride-alkaline post-deposition treatments. (PDT). To reach competitive efficiency values, it is necessary to focus on the improvement of CIGS interface. In this work, we focus on the study of the structural, morphological and optoelectronic properties in the interface of CIGS and alumina (Al2O3) which has the potential to be used as front passivation layer. We can conclude that the structural and morphological properties of CIGS remain the same with the deposition of Al2O3. When it was deposited the CdS, on Al2O3, the Al2O3 layer does not resist to the CdS chemical bath deposition. The interface Al2O3/CIGS has a low density of defects value, which is one of the desired properties of a passivation layer. This study demonstrates the potential of using Al2O3 as a front passivation layer with alternative buffer layers to CdS that do not use chemical processes during the deposition.info:eu-repo/semantics/publishedVersio

    Oral treatment with Saccharomyces cerevisiae strain UFMG 905 modulates immune responses and interferes with signal pathways involved in the activation of inflammation in a murine model of typhoid fever

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    AbstractSalmonella spp. are Gram-negative, facultative, intracellular pathogens that cause several diarrheal diseases ranging from self-limiting gastroenteritis to typhoid fever. Previous results from our laboratory showed that Saccharomyces cerevisiae strain UFMG 905 isolated from ‘cachaça’ production presented probiotic properties due to its ability to protect against experimental infection with Salmonella enterica serovar Typhimurium. In this study, the effects of oral treatment with S. cerevisiae 905 were evaluated at the immunological level in a murine model of typhoid fever. Treatment with S. cerevisiae 905 inhibited weight loss and increased survival rate after Salmonella challenge. Immunological data demonstrated that S. cerevisiae 905 decreased levels of proinflammatory cytokines and modulated the activation of mitogen-activated protein kinases (p38 and JNK, but not ERK1/2), NF-κB and AP-1, signaling pathways which are involved in the transcriptional activation of proinflammatory mediators. Experiments in germ-free mice revealed that probiotic effects were due, at least in part, to the binding of Salmonella to the yeast. In conclusion, S. cerevisiae 905 acts as a potential new biotherapy against S. Typhimurium infection due to its ability to bind bacteria and modulate signaling pathways involved in the activation of inflammation in a murine model of typhoid fever
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