Effect of different feeding levels on the production of Heterobranchus bidorsalis in outdoor concrete tanks

Fry of Heterobranchus bidorsalis (mean weight, 0.03g) were fed at 10, 20, 30, 40 or 50% of their body weight (bw)/day in outdoor concrete tanks in New Bussa, Nigeria. The fry attained the highest average weight of 6.66g in 10 weeks when fed at 40% bw/day. Feed conversion ratio ranged from 2.13 to 9.65, the protein efficiency ratio from 1.33 to 5.93. Results indicated that H. bidorsalis are efficient feed converters. Feed intake was significantly different (p<0.05) between the treatments, specific growth rate (SGR), daily growth rate (DGR), production and average weight gain indicated that 40% of fish biomass was the optimum feeding level

Controllable group velocity of the probe light in a Lambda-type system with two fold levels

The group velocities of the probe laser field are studied in a A-type system where one lower state has two fold levels coupled by a control field. It is found that the interaction of double dark states leads to controllable group velocity of the probe field in this system. It can be easily realized, due to the interacting double dark resonances, that one of the group velocities at transparency positions is much slower than the other by tuning the control field to be off resonance. In particular, when the control field is on resonance. we can obtain two equal slow group velocities with a broader EIT width, which provides potential applications in quantum storage and retrieval of light. (c) 2005 Elsevier B.V. All rights reserved.

Growth response of Heterobranchus longifilis fingerlings fed with varying levels of dietary freshwater mussel (Aspatharia sinuata)

A common bivalve: Freshwater mussel, Aspatharia sinuate was evaluated as a dietary protein supplement in the production diet for Heterobranchus longifilis fingerlings with mean body weight 8.34 plus or minus 10g reared in aquaria tanks. Four diets containing fishmeal protein at a rate of 25%, 50% and 75% along with the freshwater mussel flesh were formulated. The diet without the freshwater mussel served as the control. The fish fingerlings were fed at 5% body weight per day for 56 days. It was revealed at the end of the experiment that freshwater mussel was most suitable as a protein supplement when incorporated at 25% replacement. The body weight gain, specific growth rate and feed conversion ration values of 6.83g, 1.06% day and 0.62 respectively were highest in diet with 25% replacement closely followed by diet with 50% replacement. Beyond 75% inclusion level there was no significant growth (P>0.05). However, complete replacement of fishmeal by freshwater mussel decreases growth rates and should not be used in Heterobranchus longifilis diets

Haematological response of Heterobranchus longifilis fed varying dietary protein levels

Hematological effects of feeding varying dietary crude proteins levels to one hundred and fifty (150) H.longifilis fingerlings was examined on biweekly basis. The fingerlings of mean weights 1.26g plus or minus 0.24g were stocked in eight hapa nets (1mx1m) at 15 fingerlings per hapa. Four experimental diets with crude protein; 35%, 40%, 45% and 50% coded diet 1-4 respectively were fed to the fish for 8 weeks. The blood sample was taken and examined for packed cell volume (PCV) total protein (TP) Hemoglobin (Hb), Serum album, Erythrocyte count (RBC), while blood cell (WBC) mean corpuscle volume (MCV) and mean corpuscle hemoglobin, concentration (MCHC). There was an increase in the values of the hematological indices studied with increase in protein inclusion levels. A higher positive correlation with no significant difference (P greater than or equal to 0.05) exists between the treatments RBC, WBC, Hb and TP. The best RBC (2.10x10 super(6) count/l). WBC (7.65x10 super(4) count/l), PCV (35.4%) and Hb (5.79mg/l) were presented in fingerlings fed 40% crude protein followed by 45% crude protein. The dietary crude protein of 40% is recommended for H. longifilis for sound and healthy condition

Growth performance of Heteroclarias fed maggot meal at varying inclusion levels

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

A via L-arginina-óxido nítrico no transtorno depressivo e sua associação com a função plaquetária e o estresse oxidativo

O transtorno depressivo (TD) é um fator de risco cardiovascular independente que apresenta elevada morbi-mortalidade. Recentes evidências sugerem a participação do óxido nítrico (NO), potente vasodilatador e anti-agregante plaquetário, na patogênese de doenças cardiovasculares e psiquiátricas. A síntese do NO ocorre através da conversão do aminoácido L-arginina em L-citrulina e NO, pela ação da enzima NO sintase (NOS). Esta tese aborda o papel da via L-arginina-NO em plaquetas de pacientes com TD e sua associação com a função plaquetária e estresse oxidativo. Para análise comportamental da depressão em modelo animal, foi utilizado o modelo de estresse pós-natal de separação única (SMU). Os animais foram divididos em quatro grupos para a realização do estudo: Grupo Controle Sedentário (GCS), Grupo Controle Exercício (GCE), Grupo SMU Sedentário (SMUS) e Grupo SMU Exercício (SMUE). O treinamento físico (TF) dos animais englobou 8 semanas, com duração de 30 minutos e uma velocidade de treinamento estabelecida pelo teste máximo (TE). Para o estudo em humanos, 10 pacientes com TD com score Hamilton: 201, (média de idade: 384anos), foram pareados com 10 indivíduos saudáveis (média de idade: 383anos). Os estudos em humanos e animais foram aprovados pelos Comitês de Ética: 1436 - CEP/HUPE e CEUA/047/2010, respectivamente. Foi mensurado em humanos e em animais: transporte de L-arginina, concentração GMPc, atividade das enzimas NOS e superóxido dismutase (SOD) em plaquetas e cortisol sistêmico. Experimentos realizados somente em humanos: expressão das enzimas NOS, arginase e guanilato ciclase através de Western Blotting. A agregação plaquetária foi induzida por colágeno e foi realizada análise sistêmica de proteína C-reativa, fibrinogênio e L-arginina. Para o tratamento estatístico utilizou-se três testes estatísticos para avaliar as diferenças das curvas de sobrevida: Kaplan-Meier, e os testes de Tarone-Ware e Peto-Prentice. Em humanos, houve uma redução do transporte de L-arginina, da atividade das enzimas NOS e SOD, e da concentração de GMPc em plaquetas, e nas concentrações plasmáticas de L-arginina no grupo com TD em relação ao grupo controle. Foi observado um aumento dos níveis plasmáticos de fibrinogênio no TD. Esses resultados demonstram uma inibição da via L-arginina-NO-GMPc e da enzima anti-oxidante SOD em pacientes com TD sem afetar a função plaquetária. Em relação ao TF, para o modelo animal, foram encontradas alterações iniciais quanto à distância percorrida e tempo de execução do TE entre os grupos controles e o grupos SMUs, apresentando estes últimos menores valores para o TE. Após 8 semanas de TF, verificou-se um maior influxo no transporte de L-arginina para o SMUE em comparação ao grupo SMUS. As diferenças observadas para o tempo e a distância percorrida no TE inicial entre os grupos controle e no modelo de estresse foram revertidas após as 8 semanas de TF, demonstrando o efeito benéfico do exercício físico na capacidade cardiorespiratória em modelos de depressão.

Nuclear Energy Levels of ^31S and ^33Cl

The reaction ³²S(³He, α) ³¹S has been used to locate 42 levels in ³¹S. For 11 of the first 17 levels ℓ_n-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: E_X, J^π = 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.

Number of phase levels of a Talbot array illuminator

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.

Nuclear reactions leading to energy levels of Ar37 and K37

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 E_d = 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.

Advisory report on nutrient levels and related ecology of Malham Tarn

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.

A survey of aquatic invertebrates of the Somerset Levels, August 13-14, 1981

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.

Electromagnetic decay of the 1.7- and 2.43-MeV levels in ^9Be

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 90^o 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 Γ_rad/Γ. Analysis of 384 observed events gives Γ_rad/Γ = (1.16 ± 0.14) X 10^-4 for the 2.43-MeV level. Combining this ratio with the value of Γ_rad = 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, Γ_rad/Γ ≤ 2.4 = 10^-5, was determined.

Determination of electronic energy levels of molecules by 90° low energy electron scattering

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, B³π_g, a’π_g, and C³π_u, the carbon monoxide a³π, the ethylene ᾶ³B_1u, and the benzene ᾶ³B_1u 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.