Global dynamics of some systems of rational difference equations

AbstractIn this paper, we study the qualitative behavior of some systems of second-order rational difference equations. More precisely, we study the equilibrium points, local asymptotic stability of equilibrium point, unstability of equilibrium points, global character of equilibrium point, periodicity behavior of positive solutions and rate of convergence of positive solutions of these systems. Some numerical examples are given to verify our theoretical results

Deficient intakes of energy and macronutrients in Pakistani female students assessed by composite samples method

The main purpose of the study was to compare the energy and macronutrients intakes by composite sample method. Duplicate food samples for seven days i.e., breakfast, lunch and dinner and whatever else ate during the week were analyzed for macronutrients consumption. Twenty female students were registered from the female hostel of the NWFP, Agricultural University Peshawar Pakistan. Age, weight, height and skin folds of the students were recorded on the day of the registration. From the anthropometry Basal Metabolic Index (BMI) was determined. The composite food samples were analyzed for protein, carbohydrates and fats. The energy values were determined by multiplying the daily eaten protein, carbohydrates and fats with 4, 4 and 9, respectively. The mean values of energy and macronutrients intakes were compared with the norms as appropriate. The energy and protein intakes were lower by -29.34% and protein intake was higher by 42.65% compared with American Dietetic Association (ADA). Similarly, compared to the WHO/FAO values the energy was lower -30.57 and protein was higher by 43.29, respectively. The energy contribution was higher from protein by 151% and lower from carbohydrates and fats by -28.35 and 23.43%, respectively. This study suggests that students are having deficient or imbalance energy intakes from macronutrients and are at the risk of malnutrition

Phase-shift Cavity Ring-down Technique for Detection of NO2 in PPM Concentration

A phase-shift cavity ring-down spectroscopy (PS-CRDS) experimental set-up has been established using a broadband diode laser for the measurement of phase shift due to absorption of NO2 in a sealed off cavity ring-down cell. The PS-CRDS technique is verified by optimising various parameters of CRDS cavity and excitation laser. The PS-CRDS signals were measured on the first harmonics using a lock-in-amplifier. The square modulated laser pulses were used in the experiment to obtain the decay time. Measurements of the signal strengths at different CRDS cavity lengths wre also carried out to verify the detection sensitivity for ppm level concentration measurement of trace gases.Defence Science Journal, Vol. 64, No. 5, September 2014, pp.426-430, DOI:http://dx.doi.org/10.14429/dsj.64.503

Phase-shift Cavity Ring Down Spectroscopy Set-up for NO2 Sensing : Design and Fabrication

An indigenously designed cavity ring down spectroscopy cell of 80 cm length of mild steel material was fabricated by attaching two 1″ diameter high reflecting concave mirrors with reflectivity 99.997 % at 405 nm and radius of curvature was 1 m in specially designed mirror holding assemblies to the cell at two ends. Fine alignment of the resonator is facilitated with three tip-tilt adjusting screws to the mirror-mounting plate assembly. The PS-CRDS experimental set-up is evaluated by measuring the phase shift values corresponding to the absorption of NO2 gas filled at low pressures in the cell. The limit of detection of pure NO2 using the set-up under given conditions of Ar @ 50 mbar is estimated to be 1.50 × 1011 cm-3 and @ 60 mbar as 2 × 1011 cm-3.Defence Science Journal, Vol. 65, No. 1, January 2015, pp.25-30, DOI:http://dx.doi.org/10.14429/dsj.65.779

Quality aspects of some exportable dried fishery products of Bangladesh

A study was conducted to evaluate the quality aspects of eight exportable dried fishery products of Bangladesh. The products were evaluated by examining organoleptic properties, water reconstitution behavior, microbiological and biochemical aspects. The water reconstitution rate was faster in ribbon fish and Bombay duck, and slower in other fishes and air bladder and shark fin products. Organoleptic and physical characteristics in respect of color, odor, texture, insect infestation and broken pieces of the products revealed that all of the products were either in excellent or acceptable condition. Total viable bacterial load ranged from 0.95 x 104 CFU/g to 1.8 x 104 CFU/g in dried products. Coliform bacteria was absent in all the dried fishery products. The results of moisture, crude protein, lipid and ash content of the products ranged from 16.20 to 23.51%, 58.37 to 82.86%, 0.17 to 14.44% and 0.58 to 9.23%, respectively. Non-protein nitrogen (NPN) contents were in the range of 0.104 to 2.372% and the pepsin digestibility values were of 88.41 to 94.23%. The results of the study suggested that the exportable dried products were of good quality and hygienically safe

Biology of the penaeid shrimp populations exploited by Estuarine Set Bagnet

Results of analysis of part of the data collected during October, 1989 to December, 1990 are given on the biology and catch assessment studies on the Estuarine Set Bagnet (ESBN) from six sampling stations covering the entire coast line of Bangladesh. Length frequency analysis of seven most commonly occurring penaeid shrimp species have been done with complete ELEFAN software package. The result of exploitation patterns indicate that all penaeids except P. stylifera are being over exploited on their way back to the Sea from the nursery ground. This appeared to be the instances of serious growth over fishing. These species are exploited at a size much lower than the length at first maturity, which strongly suggests a complete withdrawal of the bagnet fishery from the coast of Bangladesh

Genetic diversity studies in common bean (Phaseolus vulgaris L.) using molecular markers

Molecular characterization of thirteen common bean genotypes was done with random amplified polymorphic DNA (RAPD) markers. Initially, 15 primers were screened out of which only seven were selected which generated a total of 65 amplification products out of which 63 bands (96.62%) were polymorphic indicating fair amount of polymorphism. The genotypes shared 43% genetic similarity among themselves. Cluster analysis delineated the genotypes into three groups with seven, five and one genotype in cluster-I, II and III, respectively. The maximum similarity index (82.35) based dice similarity coefficient was obtained between SKUA-R-21 and SKUA-R-19, while it was minimum (27.72) between genotypes PBG-29 and SKUA-R-01.Key words: Genetic divergence, common bean, random amplified polymorphic DNA (RAPD)

Development of a single combined microencapsulated formulation of allopurinol and nimesulide and investigation of their release behaviours

The aim of this study was to develop a single combined once-daily sustained release microencapsulated dosage form of Allopurinol and Nimesulide using Ethyl cellulose as release controlling factor and to evaluate drug release parameters as per various release kinetic models. In order to achieve required sustained release profile, microparticles were prepared using coacervation thermal change technique. The formulated microparticles were also characterized by physical and chemical parameters and results were found in acceptable limits. Different dissolution models were applied to drug release data in order to evaluate release mechanisms and kinetics. The drug release data fit well to the Higuchi expression. Drug release mechanism was found as a complex anomalous one