A preliminary study of the effect of mantis shrimp as an ingredient in Penaeus indicus postlarval diets

The apparent digestibility (Da) of five diets, incorporated with mantis shrimp at levels of to, 15, 20, 25 and 30% was determined for Penaeus indicus postlarvae (initial weight ranging from 0.087-0.106 g). Oa for crude protein ranged from 61.97 to 92.76% showing a significant increase with increase in the level of mantis shrimp upto 25% in the diet and was higher than the control value of 66.09 (P > 0.05). Crude fat digestibility ranged from 52.26 to 89.57% also showing an increase upto 25% incorporation of mantis shrimp

Infra-red stable fixed points of Yukawa couplings in non-minimal supersymmetric standard model with R-parity violation

We study the renormalization group evolution and the infra-red stable fixed points of the Yukawa couplings of the non-minimal supersymmetric standard model (NMSSM) with R-parity violation. Retaining only the R-parity violating couplings of higher generations, we analytically study the solutions of the renormalization group equations of all the couplings of the model. We find that there are no simultaneous non-trivial infra-red fixed points for all the couplings of the model, and that the infra-red fixed point structure of the model is similar to the MSSM with R-parity violation. In particular, we show that only the baryon number violating coupling $\lambda^{''}_{233}$, together with top- and bottom-quark Yukawa couplings, approaches a non-trivial infra-red stable fixed point. However, this fixed point solution predicts a top-quark Yukawa coupling which is incompatible with the top quark mass for any value of $\tan\beta$.Comment: 12 pages, latex, no figures. To appear in Phys. Lett.

Influence of probiotic bacterium Lactobacillus acidophilus on the survival and growth of pearl oyster Pinctada fucata spat

Combination of micro-alga Chaetoceros calcitrans and the probiotic bacterium Lactobacillus acidophilus evaluated at 1:1 and 1:2 levels revealed that in the probiotic treated group, Pinctada fucata spat registered significantly high survival of 79.7 and 89.0 % (P<0.05) respectively compared to that of 65.0 % survival in control. The probiotic treated groups also showed significant improvement in growth in terms of length and weight as compared to the control group. The probiotic treated spat attained a weight gain of 346.0 ± 1.57 mg (1:1 level) and 382.0 ± 11.76 mg (1:2 level) compared to 296.4 ± 9.04 mg in control group. The length in terms of dorso-ventral measurement (DVM) increased to 18.68 mm (1:1 level) and 19.6 (1:2 level) mm compared to 13.56 mm in control group

Nutritional composition of rotifer (Brachionus plicatilis Muller) cultured using selected natural diets

The rotifer (Brachionus plicatilis Muller) was cultured by feeding on phytoplankton monocultures (Nannochloropsis sp. and Isochrysis galbana), mixed algal cultures (Nannochloropsis sp. + Isochrysis galbana; at 1:1 ratio), and a probiotic culture (Nannochloropsis sp. + Bacillus licheniformis MTCC 6824 at 1:1 ratio). Biochemical compositions of rotifers fed on different diets were determined on day 4 of the culture. Protein and total lipid levels were the maximum when fed with I. galbana (46.02 ± 0.226% and 36.1 ± 0.07% respectively). Though dry matter content was the highest in the probiotic culture (5.4 ± 0.1%), ash free dry weight was the highest for those fed with Nannochloropsis sp. Carbohydrate was the highest (14.62 ± 0.1%) in rotifers fed with Nannochloropsis sp. Total amino acids excluding tryptophan was found to be 28.93 g 100 g rotifer-1 when fed with Nannochloropsis sp. The maximum energy content per gram dry rotifer sample was 17.61 K calories when fed with Nannochloropsis sp. Rotifer density, lipid, carbohydrate and protein content of rotifers fed with I. galbana and Nannochloropsis sp. indicate that these are the most suitable diets for the rotifer

Guaiane sesquiterpenes from seaweed Ulva fasciata Delile and their antibacterial properties

Two new guaiane sesquiterpene derivatives, guai-2-en-10a-ol (1) and guai-2-en-10a-methanol (2), were chromatographically purified as major constituents of the CHCl3/CH3OH (1:1, v/v) soluble fraction of Ulva fasciata. Acetylation of 2 furnished guai-2-en-10a-methyl methanoate (3) with acetyl group at C11 position. The structures of the compounds were elucidated using one and two-dimensional NMR and mass spectrometric analysis. Compounds 2 and 3 exhibited significant inhibition to the growth of Vibrio parahaemolyticus with minimum inhibitory concentrations of 25 and 35 mg/mL, respectively. The electronegative C10 acetyl group with high polarisability (7.02� 10�24 cm3) in 3 appeared to withdraw electron cloud from substituted cycloheptyl ring and (R)-3-methylcyclohept-1-ene moiety, thus acting as the nucleophilic center of the molecule resulting in high bioactivity

Superconductivity in Ru substituted BaFe2-xRuxAs2

The occurrence of bulk superconductivity at ~22 K is reported in polycrystalline samples of BaFe2-xRuxAs2 for nominal Ru content in the range of x=0.75 to 1.125. A systematic suppression of the spin density wave transition temperature (TSDW) precedes the appearance of superconductivity in the system. A phase diagram is proposed based on the measured TSDW and superconducting transition temperature (TC) variations as a function of Ru composition. Band structure calculations, indicate introduction of electron carriers in the system upon Ru substitutiom. The calculated magnetic moment on Fe shows a minimum at x=1.0, suggesting that the suppression of the magnetic moment is associated with the emergence of superconductivity. Results of low temperature and high field Mossbauer measurements are presented. These indicate weakening of magnetic interaction with Ru substitutionComment: 20 pages 10 figure

Selection of specific cell wall antigen for rapid detection of fish pathogenic Vibrio parahaemolyticus by enzyme immunoassay

An enzyme linked immunosorbant assay (ELISA) was developed, using polyclonal antibodies against a specific cell surface protein of Vibrio parahaemolyticus, for rapid detection of the organism. Nine virulent strains and one type strain of V. parahaemolyticus, one strain each of Vibrio vulnificus and Vibrio alginolyticus were used for the study. Cell surface proteins were extracted from all the strains and were analysed by SDS PAGE. One distinct band with molecular weight of 34 kDa, abundant in all the V. parahaemolyticus strains and lacks in other Vibrio species, was selected as cell wall antigen for immunisation. Polyclonal antibodies were raised against the selected 34 kDa protein of V. parahaemolyticus after preparative electrophoresis. An indirect plate ELISA was developed using this antiserum for detection of crude cell surface protein as well as whole cells of V. parahaemolyticus. All the 9 virulent strains and one type strain of V. parahaemolyticus tested, produced positive results, using the ELISA technique. To assess the specificity of the polyclonal serum, cross reaction studies with other Vibrio species such as V. vulnificus and V. alginolyticus were conducted by indirect plate ELISA. The results have clearly shown that antibodies directed against 34 kDa cell surface protein can be used for specific detection of fish pathogenic V. parahaemolyticus

A Comparative Study of Redundant Constraints Identification Methods in Linear Programming Problems

The objective function and the constraints can be formulated as linear functions of independent variables in most of the real-world optimization problems. Linear Programming (LP) is the process of optimizing a linear function subject to a finite number of linear equality and inequality constraints. Solving linear programming problems efficiently has always been a fascinating pursuit for computer scientists and mathematicians. The computational complexity of any linear programming problem depends on the number of constraints and variables of the LP problem. Quite often large-scale LP problems may contain many constraints which are redundant or cause infeasibility on account of inefficient formulation or some errors in data input. The presence of redundant constraints does not alter the optimal solutions(s). Nevertheless, they may consume extra computational effort. Many researchers have proposed different approaches for identifying the redundant constraints in linear programming problems. This paper compares five of such methods and discusses the efficiency of each method by solving various size LP problems and netlib problems. The algorithms of each method are coded by using a computer programming language C. The computational results are presented and analyzed in this paper

Environmental impact assessment in the shrimp farming areas of Nagapattinam Quaid-E-Milleth district, Tamil Nadu

To assess the effects of shrimp farming on the environment and on the coastal population, a study was undertaken by a team of scientific and technical staff of CMFRl in Nagapattinam Quaid-e-Milleth district, Tamil Nadu in September, 1995. Several small and large farms and corporate farms in nine coastal places, where a number of farms are located were covered in the study. With the help of the mobile laboratory of the CMFR Institute, the team collected and aneilysed soil, water and plankton samples in the inlet and outlet of the farm areas, shrimp ponds and from the wells of the nearby villages. Estimations on hydrological parameters, nutrients and total and differential counts of bacteria in the water and soil samples were made following standard procedures