Uso da criopreservação de embriões como ferramenta de aceleração de incremento da produção animal de ovinos explorados no semi-árido da região Nordeste do Brasil.

Portanto, os objetivos deste trabalho foram, verificar a viabilidade da produção in vivo de embriões ovinos da raça Dorper no semi-árido do Nordeste brasileiro e avaliar a resposta ovariana e estral de receptoras de embriões submetidas ao tratamento de sincronização do estro, utilizando duas doses de eCG

Efeito da dose de eCG sobre a atividade estral de cabras da raça Boer exploradas na região semi-árida do Nordeste do Brasil.

O objetivo desse trabalho foi avaliar a resposta estral de cabras da raça Boer, quando exploradas no semi-árido nordestino, após sincronização do estro utilizando duas diferentes doses de gonadotrofina coriônica eqUina (eCG). Foram utilizadas 13 cabras divididas em dois tratamentos hormonais de sincronização do estro, como a seguir: Grupo 1 (n = 7) esponja intra-vaginal contendo 60 mg de acetato de medroxiprogesterona (MAP) durante 11 dias. Dois dias antes da retirada das esponjas (dia 9), foi aplicado 75 ug de cloprostenol e 200 UI de eCG. No Grupo 2 (n = 6), foi utilizado o mesmo protocolo hormonal, diferindo apenas na dose de eCG, onde foi aplicado 400 UI. Todos os animais manifestaram estro em ambos os tratamentos. O intervalo entre a retirada da esponja e o início do estro (18,3 +- 6,0 x 20, 7 +- 7,3), bem como, a duração do estro (38,9 +- 10,5 x 40,7 +- 11,7) não diferiu (P>O,05) entre os Grupos 1 e 2, respectivamente. Os tratamentos utilizados mostraram uma forte sincronia, pois 92,3 % das fêmeas manifestaram estro até às 28 h após a retirada das esponjas. Duzentas unidades internacionais de eCG foi tão eficaz quanto o de 400 UI de eCG para sincronização do estro de cabras Boer. A fertilidade deveria ser investigada após a inseminação artificial

A hypothalamic-thalamostriatal circuit that controls approach-avoidance conflict in rats

Survival depends on a balance between seeking rewards and avoiding potential threats, but the neural circuits that regulate this motivational conflict remain largely unknown. Using an approach-food vs. avoid-predator threat conflict test in rats, we identified a subpopulation of neurons in the anterior portion of the paraventricular thalamic nucleus (aPVT) which express corticotrophin-releasing factor (CRF) and are preferentially recruited during conflict. Inactivation of aPVTCRF neurons during conflict biases animal’s response toward food, whereas activation of these cells recapitulates the food-seeking suppression observed during conflict. aPVTCRF neurons project densely to the nucleus accumbens (NAc), and activity in this pathway reduces food seeking and increases avoidance. In addition, we identified the ventromedial hypothalamus (VMH) as a critical input to aPVTCRF neurons, and demonstrated that VMH-aPVT neurons mediate defensive behaviors exclusively during conflict. Together, our findings describe a hypothalamic-thalamostriatal circuit that suppresses reward-seeking behavior under the competing demands of avoiding threats.Fil: Engelke, D. S.. The University of Texas Health Science Center; Estados UnidosFil: Zhang, X. O.. The University of Texas Health Science Center; Estados UnidosFil: O’Malley, J. J.. The University of Texas Health Science Center; Estados UnidosFil: Fernandez Leon, Jose Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. Sede Olavarría del Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aire. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. Sede Olavarría del Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; ArgentinaFil: Li, S.. University of Manitoba; CanadáFil: Kirouac, G. J.. University of Manitoba; CanadáFil: Beierlein, M.. The University of Texas Health Science Center; Estados UnidosFil: Do Monte, F. H.. The University of Texas Health Science Center; Estados Unido

Teor de óleo e composição de ácidos graxos em acessos de pinhão manso.

O presente trabalho teve como objetivo determinar teores de óleo em amêndoas de 17 acessos de pinhão manso, bem como realizar a caracterização química dos ácidos graxos componentes dos triacilgliceróis do óleo, com o intuito de selecionar acessos com altos teores de lipídios e composição química com predominância do ácido oléico em relação ao linoleico, uma vez que o mesmo é menos susceptível a oxidação

Total carotenoid content, a-carotene and b-carotene, of landrace pumpkins (Cucurbita moschata Duch): a preliminary study.

Landrace pumpkins occur in nature and their potential as source of pro-vitamin A may be investigated in order to be used in conventional plant breeding or biofortification programs, aiming to increase the total carotenoids and b-carotene contents. The objective of the study was to determine the total carotenoid, a-carotene, b-carotene and its isomers and contents in two landrace samples (A and B) of raw pumpkins (Cucurbita moschata) to verify its seed production potential.High Performance Liquid Chromatography andUV/Visible spectrophotometrywere used to determine a-carotene, b-carotene and its isomers, and total carotenoid contents, respectively. All analyses were carried out in triplicate. The results showedmean total carotenoid contents of 404.98 in sample A, and 234.21 ug/g in sample B. The a-carotene contents varied from 67.06 to 72.99 ug/g in samples A and B, respectively. All E-b-carotene was the most abundant isomer found varying from 244.22 to 141.95 ug/g in samples A and B, respectively. The 9 and 13-Z-b-carotene isomers were still found in lowconcentrations in both analyzed landrace samples. The content of b-carotene inrawsampleAshowed to be promising for the production of seeds for cultivation and consumption

Fermi-LAT Study of Gamma-ray Emission in the Direction of Supernova Remnant W49B

We present an analysis of the gamma-ray data obtained with the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope in the direction of SNR W49B (G43.3-0.2). A bright unresolved gamma-ray source detected at a significance of 38 sigma is found to coincide with SNR W49B. The energy spectrum in the 0.2-200 GeV range gradually steepens toward high energies. The luminosity is estimated to be 1.5x10^{36} (D/8 kpc)^2 erg s^-1 in this energy range. There is no indication that the gamma-ray emission comes from a pulsar. Assuming that the SNR shell is the site of gamma-ray production, the observed spectrum can be explained either by the decay of neutral pi mesons produced through the proton-proton collisions or by electron bremsstrahlung. The calculated energy density of relativistic particles responsible for the LAT flux is estimated to be remarkably large, U_{e,p}>10^4 eV cm^-3, for either gamma-ray production mechanism.Comment: 9 pages, 10 figure

Fermi Large Area Telescope Observations of the Cosmic-Ray Induced gamma-ray Emission of the Earth's Atmosphere

We report on measurements of the cosmic-ray induced gamma-ray emission of Earth's atmosphere by the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. The LAT has observed the Earth during its commissioning phase and with a dedicated Earth-limb following observation in September 2008. These measurements yielded 6.4 x 10^6 photons with energies >100MeV and ~250hours total livetime for the highest quality data selection. This allows the study of the spatial and spectral distributions of these photons with unprecedented detail. The spectrum of the emission - often referred to as Earth albedo gamma-ray emission - has a power-law shape up to 500 GeV with spectral index Gamma = 2.79+-0.06.Comment: Accepted for publication in PR

Fermi Large Area Telescope Measurements of the Diffuse Gamma-Ray Emission at Intermediate Galactic Latitudes

The diffuse Galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray Observatory indicated excess gamma-ray emission > 1 GeV relative to diffuse Galactic gamma-ray emission models consistent with directly measured CR spectra (the so-called ``EGRET GeV excess''). The excess emission was observed in all directions on the sky, and a variety of explanations have been proposed, including beyond-the-Standard-Model scenarios like annihilating or decaying dark matter. The Large Area Telescope (LAT) instrument on the Fermi Gamma-ray Space Telescope has measured the diffuse gamma-ray emission with improved sensitivity and resolution compared to EGRET. We report on LAT measurements of the diffuse gamma-ray emission for energies 100 MeV to 10 GeV and Galactic latitudes 10 deg. <= |b| <= 20 deg. The LAT spectrum for this region of the sky is well reproduced by a diffuse Galactic gamma-ray emission model that is consistent with local CR spectra and inconsistent with the EGRET GeV excess.Comment: 2 figures, 1 table, accepted by Physical Review Letters, available online Dec. 18th, 200

Fermi Large Area Telescope observations of the Vela-X Pulsar Wind Nebula

We report on gamma-ray observations in the off-pulse window of the Vela pulsar PSR B0833-45, using 11 months of survey data from the Fermi Large Area Telescope (LAT). This pulsar is located in the 8 degree diameter Vela supernova remnant, which contains several regions of non-thermal emission detected in the radio, X-ray and gamma-ray bands. The gamma-ray emission detected by the LAT lies within one of these regions, the 2*3 degrees area south of the pulsar known as Vela-X. The LAT flux is signicantly spatially extended with a best-fit radius of 0.88 +/- 0.12 degrees for an assumed radially symmetric uniform disk. The 200 MeV to 20 GeV LAT spectrum of this source is well described by a power-law with a spectral index of 2.41 +/- 0.09 +/- 0.15 and integral flux above 100 MeV of (4.73 +/- 0.63 +/- 1.32) * 10^{-7} cm^{-2} s^{-1}. The first errors represent the statistical error on the fit parameters, while the second ones are the systematic uncertainties. Detailed morphological and spectral analyses give strong constraints on the energetics and magnetic field of the pulsar wind nebula (PWN) system and favor a scenario with two distinct electron populations.Comment: 21 pages, 5 figures, accepted for publication in Astrophysical Journa