1,768 research outputs found
Resposta fisiológica de ovinos da raça Santa Inês alimentados com diferentes níveis de farelo de manga em substituição ao milho.
O experimento foi delineado para avaliar o efeito da substituição do milho por farelo de manga e medir os efeitos das condições climáticas ao longo do dia sobre os parâmetros fisiológicos: temperatura retal (TR), temperatura Superficial (TS) e freqüência respiratória (FR), em ovinos da raça Santa Inês, criados em confinamento em clima semi-árido. Ovinos machos castrados (n = 16) foram submetidos a quatro dietas com diferentes níveis de substituição do milho por farelo de manga. A TR, TS e FR foram medidas a cada hora durante dois períodos de 24 horas. Adotou-se o delineamento de blocos casualizados, com quatro repetições, em esquema fatorial 4 x 12 (níveis de inclusão de farelo de manga x horários de avaliação dos parâmetros fisiológicos). Não foi observado influência da dieta na TR, TS e FR dos ovinos, entretanto observou-se a influência das condições climáticas
Comportamento ingestivo de ovinos alimentados com diferentes níveis de manga em substituição ao milho.
Caracterização de ácidos humicos extraídos de um latossolo sob diferentes sistemas de produção de café.
Carbon pools and soil fertility in an oxisol from cerradounder different coffee production systems.
Cross-taxon congruence between predatory arthropods and plants across Mediterranean agricultural landscapes
Although arthropods are among the most diverse, abundant and ecologically important animals in terrestrial ecosystems, they are generally neglected in most biodiversity inventories due to their complex systematics and overwhelming diversity, coupled with the current decline in the number of taxonomists. For this reason, several surrogate groups for arthropod diversity have been proposed, with plants being identified as a good putative cross-taxon indicator. By sampling plants and three groups of ground-dwelling arthropods (rove beetles, ground beetles and spiders) in 300 sites across 15 landscapes including multiple semi-natural and agricultural habitats, we tested for habitat-dependence and scale-dependence in the cross-taxon congruence. Plant species richness was a poor predictor of the species richness of predatory arthropods. Among the predator groups, ground beetles appeared as the best potential surrogate for the other ground-dwelling predators. This is backed by the fact that ground beetles were extremely diverse and abundant in all habitats and are usually easier to identify than both rove beetles and spiders. Decreasing the scale at which the cross-taxon congruence was tested improved the strength of the cross-taxon congruence. Although plant species richness was not a suitable indicator for the diversity of predatory arthropods, vegetation structure played a significant role in influencing cross-taxon congruence in both natural and agricultural habitats. Our results highlight the need to explore the cross-taxon relationships at a fine habitat resolution scale, as strong correlations were obtained only by taking into account habitat identity
Resposta de diferentes genótipos de tomateiro micro-Tom à adubação com fertilizante organomineral.
Com a finalidade de determinar se a utilização do fertilizante organomineral (FOM) resulta em incremento de produção no tomateiro, realizou-se um experimento em em casa de vegetação com tomateiro 'Micro-Tom' WT (WILD TYPE) como genótipo controle e o mutante dgt (diageotropica) pouco sensível ao hormômio auxina (AIA)
Magnetic resonance imaging of ultrasmall superparamagnetic iron oxide-labeled exosomes from stem cells: a new method to obtain labeled exosomes
Purpose: Recent findings indicate that the beneficial effects of adipose stem cells (ASCs), reported in several neurodegenerative experimental models, could be due to their paracrine activity mediated by the release of exosomes. The aim of this study was the development and validation of an innovative exosome-labeling protocol that allows to visualize them with magnetic resonance imaging (MRI).Materials and methods: At first, ASCs were labeled using ultrasmall superparamagnetic iron oxide nanoparticles (USPIO, 4\u20136 nm), and optimal parameters to label ASCs in terms of cell viability, labeling efficiency, iron content, and magnetic resonance (MR) image contrast were investigated. Exosomes were then isolated from labeled ASCs using a standard isolation protocol. The efficiency of exosome labeling was assessed by acquiring MR images in vitro and in vivo as well as by determining their iron content. Transmission electron microscopy images and histological analysis were performed to validate the results obtained.Results: By using optimized experimental parameters for ASC labeling (200 \ub5g Fe/mL of USPIO and 72 hours of incubation), it was possible to label 100% of the cells, while their viability remained comparable to unlabeled cells; the detection limit of MR images was of 102 and 2.5
7103 ASCs in vitro and in vivo, respectively. Exosomes isolated from previously labeled ASCs retain nanoparticles, as demonstrated by transmission electron microscopy images. The detection limit by MRI was 3 \ub5g and 5 \ub5g of exosomes in vitro and in vivo, respectively.Conclusion: We report a new approach for labeling of exosomes by USPIO that allows detection by MRI while preserving their morphology and physiological characteristics
Bioactivity of humic acids from vermicompost at increasing maturity stages.
The aim of this work was to evaluate chemical changes and plant growth-promoting effect of HA from different maturing stages isolated from vermicompost, relating bioactivity and its chemical characteristics
Precision Measurement of the Neutron Spin Asymmetry and Spin-Flavor Decomposition in the Valence Quark Region
We have measured the neutron spin asymmetry with high precision at
three kinematics in the deep inelastic region at , 0.47 and 0.60, and
, 3.5 and 4.8 (GeV/c), respectively. Our results unambiguously
show, for the first time, that crosses zero around and becomes
significantly positive at . Combined with the world proton data,
polarized quark distributions were extracted. Our results, in general, agree
with relativistic constituent quark models and with perturbative quantum
chromodynamics (pQCD) analyses based on the earlier data. However they deviate
from pQCD predictions based on hadron helicity conservation.Comment: 5 pages, 2 figures, this is the final version appeared in Phys. Rev.
Let
Measurement of Semileptonic Branching Fractions of B Mesons to Narrow D** States
Using the data accumulated in 2002-2004 with the DO detector in
proton-antiproton collisions at the Fermilab Tevatron collider with
centre-of-mass energy 1.96 TeV, the branching fractions of the decays B ->
\bar{D}_1^0(2420) \mu^+ \nu_\mu X and B -> \bar{D}_2^{*0}(2460) \mu^+ \nu_\mu X
and their ratio have been measured: BR(\bar{b}->B) \cdot BR(B-> \bar{D}_1^0
\mu^+ \nu_\mu X) \cdot BR(\bar{D}_1^0 -> D*- pi+) =
(0.087+-0.007(stat)+-0.014(syst))%; BR(\bar{b}->B)\cdot BR(B->D_2^{*0} \mu^+
\nu_\mu X) \cdot BR(\bar{D}_2^{*0} -> D*- \pi^+) =
(0.035+-0.007(stat)+-0.008(syst))%; and (BR(B -> \bar{D}_2^{*0} \mu^+ \nu_\mu
X)BR(D2*0->D*- pi+)) / (BR(B -> \bar{D}_1^{0} \mu^+ \nu_\mu X)\cdot
BR(\bar{D}_1^{0}->D*- \pi^+)) = 0.39+-0.09(stat)+-0.12(syst), where the charge
conjugated states are always implied.Comment: submitted to Phys. Rev. Let
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