998 resultados para Vigor levels


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70-day growth trial was conducted with Heteroclarias: Heterobranchus bidorsalis X Clarias gariepinus (mean weight 0.64~c0.006g) fed diets based on various inclusion levels of Maggot Meal. The fishmeal in the control diet was replaced with maggot meals at 25%, 50%, 75% and 100% levels to supply 40% crude protein in the final diets. The trails were conducted in glass tanks (60cmx30cmx30cm). Evaluation of growth parameters and nutrient utilization of the fish was based on weight gains, protein intake, protein efficiency ratio, net protein utilization, feed conversion efficiency and carcass analysis. Best growth and feed conversion efficiency were obtained with the 75% dietary inclusion of maggot meal. There was no significant differences (P>0.055) between the group of fish on 50% and 75% dietary inclusion maggot meal in growth performance and protein efficiency ratio but, there was a significant (P<0.05) difference in the NPU (Net Protein Utilization) and protein gain between the control diet and those fed on maggot meals. There was no marked variation in the survival rate of fish on all diets

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The reaction 32S(3He, α) 31S has been used to locate 42 levels in 31S. For 11 of the first 17 levelsn-values have been determined. The first 6 excited states of 31S have been studied by applying the particle-gamma correlation method of Litherland and Ferguson (their Method II) to the reaction 32S(3He, αγ) 31S. The resulting spins and parities are: EX, Jπ = 1.25 MeV, 3/2+; 2.23 MeV, 5/2+; 3.08 MeV, 1/2+; 3.29 MeV, 5/2+, 3/2+; 3.35 MeV, 7/2, 3/2; 3.44 MeV, 3/2+. Mixing and branching ratios have also been determined. The ground state Q-value for the reaction 32S(3He, α)31S has been measured to be 5.538 ± 0.006 MeV. Analysis of the spectra of the reaction 32S(3He, α)33Cl which were obtained as a by-product of the spectra of the reaction 32S(3He, α) 31S located levels in 33Cl at the following excitation energies: 0, 810 ± 9, (1978 ± 14), 2351 ± 9, 2686 ± 8, 2848 ± 9 (a known doublet), 2980 ± 9, and 4119 ± 10 keV. The 2.0 MeV level was only weakly populated, and to confirm its existence the reaction 36Ar(p, α)33Cl has been studied. In this reaction the 2.0 MeV level was strongly populated and the measured excitation energy was 1999 ± 20 keV. The experimental results for 31S and 33Cl are compared with their analogs and with nuclear model predictions.

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The number of phase levels of a Talbot array illuminator is an important factor in the estimation of practical fabrication complexity and cost. We show that the number it) of phase levels of a Talbot array illuminator has a simple relationship to the prime number. When there is an alternative pi -phase modulation in the output array, the relations are similar. (C) 2001 Optical Society of America OCIS codes: 070.6760, 050.1950, 050.1980.

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Na matriz energética brasileira, o óleo diesel tem lugar de destaque, porém ainda é comercializado com teores de compostos sulfurados e nitrogenados considerados altos para as legislações ambientais que entrarão em vigor nos próximos anos. Tradicionalmente, a remoção desses compostos de enxofre de correntes de petróleo é realizada por processos de hidrotratamento (HDT). No entanto, devido as características do diesel brasileiro, se faz necessária maior severidade para atingir as novas especificações dos combustíveis. Isto implica em investimentos e custos operacionais crescentes para atender a demanda que se instala. Neste contexto, a adsorção está sendo estudada para a purificação da corrente de óleo diesel oriunda da etapa de hidrotratamento como polimento final para alcançar as especificações mais exigentes. Sabe-se que os adsorventes comerciais apresentam limitações na remoção destes contaminantes e uma alternativa que tem se mostrado promissora é a incorporação de metais de transição na estrutura do sólido. No presente trabalho foram modificados adsorventes comerciais, tais como aluminas, sílica-aluminas e argilas pela introdução dos elementos níquel, colbalto e molibdênio e testado o desempenho dessas modificações frente à adsorção de compostos sulfurados e nitrogenados presentes em um diesel hidrotratado. Foram feitas caracterizações químicas, físicas, texturais e morfológicas dos sólidos com e sem incorporação de metais de transição na estrutura original. Os experimentos de adsorção foram realizados a 40C. Avaliando todos os sólidos, o adsorvente que mostrou o melhor desempenho na remoção de compostos sulfurados e nitrogenados por massa de adsorvente foi a sílica-alumina sem modificações, que foi capaz de remover em torno de 90% de compostos nitrogenados e 55 % de sulfurados para 2 g de sólido / 10 mL de diesel. Para os materiais modificados, observou-se que a incorporação dos metais de transição ocasionou redução da sua área superficial e do volume total de poros. Desta maneira, os efeitos esperados pelas interações entre o sítios metálicos e os compostos de nitrogênio e enxofre foram reduzidos

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In view of recent interest in the Cl37 (ʋ solar’e-)Ar37 reaction cross section, information on some aspects of mass 37 nuclei has been obtained using the K39 (d, ∝) Ar37 and Cl35 (He3, p) Ar37 reactions. Ar37 levels have been found at 0, 1.41, 1.62, 2.22, 2.50, 2.80, 3.17, 3.27, 3.53, 3.61, 3.71, (3.75), (3.90), 3.94, 4.02, (4.21), 4.28, 4.32, 4.40, 4.45, 4.58, 4.63, 4.74, 4.89, 4.98, 5.05, 5.10, 5.13, 5.21, 5.35, 5.41, 5.44, 5.54, 5.58, 5.67, 5.77, and 5.85 MeV (the underlined values correspond to previously tabulated levels). The nuclear temperature calculated from the Ar37 level density is 1.4 MeV. Angular distributions of the lowest six levels with the K39 (d, ∝) Ar37 reaction at Ed = 10 MeV indicate a dominant direct interaction mechanism and the inapplicability of the 2I + 1 rule of the statistical model. Comparison of the spectra obtained with the K39 (d, ∝) Ar37 and Cl35 (He3, p) Ar37 reactions leads to the suggestion that the 5.13-MeV level is the T = 3/2 Cl37 ground state analog. The ground state Q-value of the Ca40 (p, ∝) K37 reaction has been measured: -5179 ± 9 keV. This value implies a K37 mass excess of -24804 ± 10 keV. Description of a NMR magnetometer and a sixteen-detector array used in conjunction with a 61-cm double-focusing magnetic spectrometer are included in appendices.

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Aspects of reported nutrient levels and their ecological implications for Malham Tarn are discussed. Discussion centres upon the data given here as appendices, involving possible evidence of a long-term increase in the concentrations of some nutrients (especially nitrate) of significance for the Tarn's ecology and conservation. Further comparative tests of some methods of chemical analysis employed in obtaining those data are reported.

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Since 1975 the wildlife interest of the Somerset Levels and Moors have been assessed. Detailed information has been obtained on the conservation interest of meadows, breeding and wintering bird populations and the botany of aquatic habitats (rhynes). Little work to date has been carried out on the terrestrial and aquatic invertebrate fauna. The prime aim of this survey was to sample a wide variety of rhynes in order to obtain information on the nature and distribution of aquatic invertebrates.

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The 1.7- and 2.43-MeV levels in 9Be were populated with the reaction 11B(d, α)9Be* by bombarding thin boron on carbon foils with 1.7-MeV deuterons. The alpha particles were analyzed in energy with a surface-barrier counter set at the unique kinematically determined angle and the recoiling 9Be nuclei at 90o were analyzed in rigidity with a magnetic spectrometer, in energy by a surface-barrier counter at the spectrometer focus, and in velocity by the time delay between an alpha and a 9Be count. When a pulse from the spectrometer counter was in the appropriate delayed coincidence with a pulse from the alpha counter, the two pulses were recorded in a two-dimensional pulse height analyzer. Most of the 9Be* decay by particle breakup. Only those that gamma decay are detected by the spectrometer counter. Thus the experiment provides a direct measurement of Γrad/Γ. Analysis of 384 observed events gives Γrad/Γ = (1.16 ± 0.14) X 10-4 for the 2.43-MeV level. Combining this ratio with the value of Γrad = 0.122 ± 0.015 eV found from inelastic electron scattering gives Γ = (1.05 ± 0.18) keV. For the 1.7-MeV level, an upper limit, Γrad/Γ ≤ 2.4 = 10-5, was determined.

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A review of the theory of electron scattering indicates that low incident beam energies and large scattering angles are the favorable conditions for the observation of optically forbidden transitions in atoms and molecules.

An apparatus capable of yielding electron impact spectra at 90° with incident electron beam energies between 30 and 50 electron volts is described. The resolution of the instrument is about 1 electron volt.

Impact spectra of thirteen molecules have been obtained. Known forbidden transitions to the helium 23S, the hydrogen b3Ʃ+u, the nitrogen A3Ʃ+u, B3πg, a’πg, and C3πu, the carbon monoxide a3π, the ethylene ᾶ3B1u, and the benzene ᾶ3B1u states from the corresponding ground states have been observed.

In addition, singlet-triplet vertical transitions in acetylene, propyne, propadiene, norbornadiene and quadricyclene, peaking at 5.9, 5.9, 4.5, 3.8, and 4.0 ev (±0.2 ev), respectively, have been observed and assigned for the first time.

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Objectives: The mechanism by which atheroma plaque becomes unstable is not completely understood to date but analysis of differentially expressed genes in stable versus unstable plaques may provide clues. This will be crucial toward disclosing the mechanistic basis of plaque instability, and may help to identify prognostic biomarkers for ischaemic events. The objective of our study was to identify differences in expression levels of 59 selected genes between symptomatic patients (unstable plaques) and asymptomatic patients (stable plaques). Methods: 80 carotid plaques obtained by carotid endarterectomy and classified as symptomatic (>70% stenosis) or asymptomatic (>80% stenosis) were used in this study. The expression levels of 59 genes were quantified by qPCR on RNA extracted from the carotid plaques obtained by endarterectomy and analyzed by means of various bioinformatic tools. Results: Several genes associated with autophagy pathways displayed differential expression levels between asymptomatic and symptomatic (i.e. MAP1LC3B, RAB24, EVA1A). In particular, mRNA levels of MAP1LC3B, an autophagic marker, showed a 5-fold decrease in symptomatic samples, which was confirmed in protein blots. Immune system-related factors and endoplasmic reticulum-associated markers (i.e. ERP27, ITPR1, ERO1LB, TIMP1, IL12B) emerged as differently expressed genes between asymptomatic and symptomatic patients. Conclusions: Carotid atherosclerotic plaques in which MAP1LC3B is underexpressed would not be able to benefit from MAP1LC3B-associated autophagy. This may lead to accumulation of dead cells at lesion site with subsequent plaque destabilization leading to cerebrovascular events. Identified biomarkers and network interactions may represent novel targets for development of treatments against plaque destabilization and thus for the prevention of cerebrovascular events.