5,679 research outputs found
Avaliação de híbridos comerciais de milho para utilização na forma de silagem na Mesorregião do Leste Alagoano
Teve-se o objetivo de avaliar o comportamento produtivo de híbridos de milho para uso na forma de silagem no Leste Alagoano. Vinte híbridos comerciais de milho destinados a Região Nordeste do Brasil foram avaliados em dois locais na Mesorregião do Leste Alagoano, Rio Largo e Teotônio Vilela, nas safras agrícolas de 2002 a 2004. Foi utilizado o delineamento de blocos casualizados com três repetições e as características avaliadas foram à produtividade de matéria seca (PMS) e o potencial de produção de leite da silagem produzida. Verificou-se a existência de variabilidade no potencial de utilização dos híbridos comerciais de milho para o emprego na alimentação animal, na forma de silagem. A amplitude de variação observada entre as médias dos híbridos foi de 2,6 t de MS/ha e de 1.397 Kg de leite/ha, respectivamente, para a PMS e o potencial de produção de leite. Na média de três anos de avaliação em dois locais, os híbridos TORK, DAS8480, AG4051, FORT, DAS657 e XB8010 foram os melhores tanto para produtividade de matéria seca quanto para o potencial de produção de leite por hectare.  
Attainment of hydrogel-thickened nanoemulsions with tea tree oil (Melaleuca alternifolia) and retinyl palmitate
We propose the development of hydrogel-thickned nanoemulsions (HTNs) with tea tree essential oil (Melaleuca alternifolia) and vitamin A palmitate (retinyl palmitate). Nanoemulsions and HTNs were produced by the use of phase inversion method, employing non-ionic surfactants. As surfactant phase were used sorbitan esters and hydrogenated/ethoxylated castor oil. HTNs with drops size ranging between 86 to 96 nm were obtained, depending on the polymer used, with increased viscosity. Rheological profile of developed HTNs was determined, showing the influence of the kind of polymer used, here all presented pseudo-plastic behaviour, with different viscosity measurement.Key words: Nanoemulsion, hydrogel-thickened nanoemulsion, essential oil, phase inversion, vitamin A, retinyl palmitate, tea tree oil
Catastrophic senescence and semelparity in the Penna aging model
The catastrophic senescence of the Pacific salmon is among the initial tests
used to validate the Penna aging model. Based on the mutation accumulation
theory, the sudden decrease in fitness following reproduction may be solely
attributed to the semelparity of the species. In this work, we report other
consequences of mutation accumulation. Contrary to earlier findings, such
dramatic manifestation of aging depends not only on the choice of breeding
strategy but also on the value of the reproduction age, R, and the mutation
threshold, T. Senescence is catastrophic when . As the organism's
tolerance for harmful genetic mutations increases, the aging process becomes
more gradual. We observe senescence that is threshold dependent whenever T>R.
That is, the sudden drop in survival rate occurs at age equal to the mutation
threshold value
Finite-size scaling considerations on the ground state microcanonical temperature in entropic sampling simulations
In this work we discuss the behavior of the microcanonical temperature
obtained by means of numerical entropic
sampling studies. It is observed that in almost all cases the slope of the
logarithm of the density of states is not infinite in the ground state,
since as expected it should be directly related to the inverse temperature
. Here we show that these finite slopes are in fact due to
finite-size effects and we propose an analytic expression for the
behavior of when . To
test this idea we use three distinct two-dimensional square lattice models
presenting second-order phase transitions. We calculated by exact means the
parameters and for the two-states Ising model and for the and
states Potts model and compared with the results obtained by entropic sampling
simulations. We found an excellent agreement between exact and numerical
values. We argue that this new set of parameters and represents an
interesting novel issue of investigation in entropic sampling studies for
different models
Angiogenesis and apatinib: a new hope for patients with advanced gastric cancer?
Amgen; Pierre Fabreinfo:eu-repo/semantics/publishedVersio
Infrared-absorption spectra associated to transitions from donor states to conduction subbands in GaAs-(Ga,Al)As quantum wells
The infrared-absorption spectra associated with transitions from donor states to conduction subbands in GaAs-(Ga,Al)As quantum wells are systematically studied. The absorption spectra are calculated within the effective-mass approximation and With a variational procedure for evaluating donor energies and envelope wave functions. Calculations are presented for incident radiation polarized both in the growth direction and in the plane perpendicular to it. Theoretical results are analyzed for different quantum-well widths and n=1,2 conduction subbands, and compared with available experimental measurements. (C) 1996 American Institute of Physics.8021142114
Correlation of HTLV-1 proviral load and lymphocyte proliferation from asymptomatic HTLV-1-positive patients and HAM/TSP patients associated or not to skin disorders
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