Teleparallel Energy-Momentum Distribution of Spatially Homogeneous Rotating Spacetimes

The energy-momentum distribution of spatially homogeneous rotating spacetimes in the context of teleparallel theory of gravity is investigated. For this purpose, we use the teleparallel version of Moller prescription. It is found that the components of energy-momentum density are finite and well-defined but are different from General Relativity. However, the energy-momentum density components become the same in both theories under certain assumptions. We also analyse these quantities for some special solutions of the spatially homogeneous rotating spacetimes.Comment: 12 pages, accepted for publication in Int. J. Theor. Phy

Fibrinogen as independent risk factor for ischemic stroke

We have studied fibrinogen levels (Clauss technique) in atherothrombotic ischemic stroke patients, in order to determine its role as a thombogenic risk factor. Twenty nine patients (20 men and 9 women) between 25 and 79 years old were studied; they all have had a atherothrombotic stroke. They were classified into two groups according to the result of their carotid doppler ultrasonography: g1 - without carotid flow reduction (n=l 9) and g2 - with carotid flow reduction (n=10). The fibrinogen mean value was 269mg/dl in gl and 353 mg/dl in g2. There were 47% of patients in gl and 80% of patients in g2 who presented levels >300 mg/dl. The proportions of the groups were significantly different (p300 mg/dl. As diferenças obtidas entre os grupos neste estudo foram significantes. Conclusão- Considerando o nível de risco epidemiológico de 300 mg/dl, nossos resultados sugerem que o fibrinogênio é um fator de risco independente para AVC aterotrombótico, especialmente naqueles com alteração de fluxo carotídeo.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de MedicinaUNIFESP, EPM, Depto. de MedicinaSciEL

Energy and Momentum densities of cosmological models, with equation of state ρ=μ\rho=\mu, in general relativity and teleparallel gravity

We calculated the energy and momentum densities of stiff fluid solutions, using Einstein, Bergmann-Thomson and Landau-Lifshitz energy-momentum complexes, in both general relativity and teleparallel gravity. In our analysis we get different results comparing the aforementioned complexes with each other when calculated in the same gravitational theory, either this is in general relativity and teleparallel gravity. However, interestingly enough, each complex's value is the same either in general relativity or teleparallel gravity. Our results sustain that (i) general relativity or teleparallel gravity are equivalent theories (ii) different energy-momentum complexes do not provide the same energy and momentum densities neither in general relativity nor in teleparallel gravity. In the context of the theory of teleparallel gravity, the vector and axial-vector parts of the torsion are obtained. We show that the axial-vector torsion vanishes for the space-time under study.Comment: 15 pages, no figures, Minor typos corrected; version to appear in International Journal of Theoretical Physic

Future environmental and agricultural impacts of Brazil's Forest Code

The role of improving the enforcement of Brazil's Forest Code in reducing deforestation in the Amazon has been highlighted in many studies. However, in a context of strong political pressure for loosening environmental protections, the future impacts of a nationwide implementation of the Forest Code on both environment and agriculture remain poorly understood. Here, we present a spatially explicit assessment of Brazil's 2012 Forest Code through the year 2050; specifically, we use a partial equilibrium economic model that provides a globally consistent national modeling framework with detailed representation of the agricultural sector and spatially explicit land-use change. We test for the combined or isolated impacts of the different measures of the Forest Code, including deforestation control and obligatory forest restoration with or without environmental reserve quotas. Our results show that, if rigorously enforced, the Forest Code could prevent a net loss of 53.4 million hectares (Mha) of forest and native vegetation by 2050, 43.1 Mha (81%) of which are in the Amazon alone. The control of illegal deforestation promotes the largest environmental benefits, but the obligatory restoration of illegally deforested areas creates 12.9 Mha of new forested area. Environmental reserve quotas further protect 5.8 Mha of undisturbed natural vegetation. Compared to a scenario without the Forest Code, by 2050, cropland area is only reduced by 4% and the cattle herd by 8%. Our results show that compliance with the Forest Code requires an increase in cattle productivity of 56% over four decades, with a combination of a higher use of supplements and an adoption of semi-intensive pasture management. We estimate that the enforcement of the Forest Code could contribute up to 1.03 PgCO<sub>2</sub>e to the ambitious GHG emissions reduction target set by Brazil for 2030

Energy Contents of Some Well-Known Solutions in Teleparallel Gravity

In the context of teleparallel equivalent to General Relativity, we study energy and its relevant quantities for some well-known black hole solutions. For this purpose, we use the Hamiltonian approach which gives reasonable and interesting results. We find that our results of energy exactly coincide with several prescriptions in General Relativity. This supports the claim that different energy-momentum prescriptions can give identical results for a given spacetime. We also evaluate energy-momentum flux of these solutions.Comment: 16 pages, accepted for publication in Astrophys. Space Sc

Produtividade de raízes de mandioca consorciada com milho e caupi em sistema orgânico.

Foram avaliados sistemas orgânicos de produção de mandioca “de mesa”, em Seropédica (RJ). O experimento constou dos seguintes tratamentos: monocultivo de mandioca (cv. IAC 576-70) e consórcios com milho experimental (cv. Eldorado), caupi (cv. Mauá) e milho+caupi. O manejo orgânico foi padronizado e toda a área experimental irrigada durante o período de permanência do milho no sistema. Do milho, foram colhidas espigas verdes (imaturas) e a parte aérea acamada na superfície do solo. O caupi foi incluído como adubo verde e cortado na floração, sendo mantidos os resíduos na superfície do solo. Ambos os consortes ocuparam as entrelinhas da mandioca, de modo alternado, semeados após a primeira capina da cultura principal. A cultivar IAC 576-70 mostrou-se adaptada ao manejo orgânico, com produtividade de raízes de padrão comercial próxima a 31 Mg ha-¹. Não houve diferenças significativas entre o monocultivo e os três tipos de consórcios testados. A inclusão do milho representou potencial de renda adicional ao produtor, colhendo-se,em média, 18.125 espigas ha-¹, o que correspondeu a 5,1 Mg ha-¹. Os resíduos provenientes da roçada do caupi proporcionaram um aporte de biomassa fresca de 12 Mg ha-¹, com uma expressiva contribuição em nitrogênio (cerca de 44 kg de N ha-1). A fabácea leguminosa cobriu por completo as entrelinhas da mandioca,demonstrando seu potencial de controle à erosão e a ervas espontâneas. O consórcio triplo mostrou-se vantajoso tendo em vista que a receita obtida com a venda do milho verde justificaria os custos da irrigação, além dos benefícios da inclusão do caupi e da não interferência dos consortes na produtividade da mandioca

Silício No Desenvolvimento In Vitro Da Orquídea Cattleya Forbesii

Addition of Silicon (Si) to culture media has been shown to improve the development of seedlings grown in vitro, and to reduce losses during the acclimatization phase. The objective of this study was to evaluate the in vitro growth of Cattleya forbesii (Orchidaceae) in MS medium containing five different concentrations of SiO2 (0.0, 0.5, 1.0, 1.5, and 2.0 g·L−1). At day 200, the following variables were measured: number of roots, average length of the root system, leaf area, number of leaves and shoots, shoot height, fresh and dry masses of roots and shoots, water content of roots and shoots, and pH of the culture medium. Most variables decreased as the concentration of Si increased, reducing the in vitro vegetative growth of C. forbesii. Accumulation of Si in leaf tissues was detected by scanning electron microscopy, confirming uptake by plants. The Si source and concentrations tested showed no beneficial effect on in vitro growth of C. forbesii. © 2016, Universidade Federal Rural do Semi-Arid. All rights reserved.291182

Current and Future Prospects of Nitro-compounds as Drugs for Trypanosomiasis and Leishmaniasis

Interest in nitroheterocyclic drugs for the treatment of infectious diseases has undergone a resurgence in recent years. Here we review the current status of monocyclic and bicyclic nitroheterocyclic compounds as existing or potential new treatments for visceral leishmaniasis, Chagas' disease and human African trypanosomiasis. Both monocyclic (nifurtimox, benznidazole and fexinidazole) and bicyclic (pretomanid (PA-824) and delamanid (OPC-67683)) nitro-compounds are prodrugs, requiring enzymatic activation to exert their parasite toxicity. Current understanding of the nitroreductases involved in activation and possible mechanisms by which parasites develop resistance is discussed along with a description of the pharmacokinetic / pharmacodynamic behaviour and chemical structure-activity relationships of drugs and experimental compounds.</p

Estimating the global conservation status of more than 15,000 Amazonian tree species

Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%. We show that the trends observed in Amazonia apply to trees throughout the tropics, and we predict thatmost of the world’s >40,000 tropical tree species now qualify as globally threatened. A gap analysis suggests that existing Amazonian protected areas and indigenous territories will protect viable populations of most threatened species if these areas suffer no further degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century

One-Liners

One liners from: N.M. Martinez-Rossi, C. Andrade-Monteiro and S.R.C. Pombeiro; M. Orbach ; H. Liu and TJ. Schmidhauser; P.A. Hubbard and C.H. Wilso