This work aims to analyze a three-dimensional discrete-time biological system, a prey-predator model with a constant harvesting amount. The stage structure lies in the predator species. This analysis is done by finding all possible equilibria and investigating their stability. In order to get an optimal harvesting strategy, we suppose that harvesting is to be a non-constant rate. Finally, numerical simulations are given to confirm the outcome of mathematical analysis.
The research aimed to use HIIT exercises, and to know the effect of HIIT exercises on some physiological and physical indicators of the young badminton players, and to identify the degree of competition anxiety and the performance of some offense skills among the young badminton players. The research community (the young badminton players), the research sample and its selection method (the research sample was chosen by the intentional method (8) badminton player from the Athwari Club), the scientific method (the experimental method with pre and post tests), measurement tools: physiological tests (high and low blood pressure) , pulse, and physical exams (explosive force of arms and legs) and the offense skills and the scale of competit
... Show MoreThe research aimed to use HIIT exercises, and to know the effect of HIIT exercises on some physiological and physical indicators of the young badminton players, and to identify the degree of competition anxiety and the performance of some offense skills among the young badminton players. The research community (the young badminton players), the research sample and its selection method (the research sample was chosen by the intentional method (8) badminton player from the Athwari Club), the scientific method (the experimental method with pre and post tests), measurement tools: physiological tests (high and low blood pressure) , pulse, and physical exams (explosive force of arms and legs) and the offense skills and the scale of competition an
... Show MoreA study on the impact of ascending levels of crude oil on the growth of transplanted seedlings ( March2005 ) of Olive (Olea europaea Linn) was carried out at the experimental area of Iraq Natural History Museum and Research centre / Baghdad University (Bab-Al-Madham –Baghdad) grown under field condition and continued till April 2008.The experiment was laid out in complete randomized design ( CRD ) with five levels of pollution (0.0 , 0.5 , 1.0 , 2.0 and 3.0 liter / seedling ) poured at the soil surface , each seedling represented one replicate and was replicated four times . Data collected from the experiment were visual symptoms , percents of seedlings death, plant height and total dry weight of harvested
... Show MoreMelatonin is a potent scavenger of reactive oxygen species or free radicals like superoxide and hydroxyl radicals. The oxidation of hemoglobin to methemoglobin (meth-Hb) by oxidizing compounds has been widely studied. The present work was designed to evaluate the ability of different concentrations of melatonin to inhibit nitrite–induced oxidation of hemoglobin. Blood samples were obtained from apparently healthy individuals from which erythrocyte hemolysate was prepared. Different concentrations of melatonin (10-9-1.0 mg/ml) were incubated for 10 min with the hemolysate, then to the resultant mixture 1 ml of sodium nitrite (final concentration 0.6 mM) was added, and the
... Show MoreThe presence of natural voids and fractures (weak zones) in subsurface gypsiferous soil and gypsum, within the University of Al-Anbar, western Iraq. It causes a harsher problem for civil engineering projects. Electrical resistivity technique is applied as an economic decipher for investigation underground weak zones. The inverse models of the Dipole-dipole and Pole-dipole arrays with aspacing of 2 m and an n-factor of 6 clearly show that the resistivity contrast between the anomalous part of the weak zone and the background. The maximum thickness and shape are well defined from 2D imaging with Dipole-dipole array, the maximum thickness ranges between 9.5 to 11.5 m. It is concluded that the 2D imaging survey is a useful technique and more
... Show More) were taken from three stations at Al-Razzazah lake,by using a range of gill nets and seine nets. A total of 318 fish were taken from all stations. The age data determined from the scales showed that there were eight age classes present in station 1 and 2 and seven age classes in station 3. The increment in length of A. latus at the area of study showed a tendency to decrease with the increase in age after the fourth year of life. The length- weight relationships of both sexes specimens are expressed by the following equations: Log ï· = -1.93 + 2.67 Log ï¬â€¦.. for station (1) fish Log ï·= -2.08 + 2.74 Log ï¬ â€¦. For station (2) fish Log ï·= -2.02 + 2.39 Log ï¬ â€¦. For station (3) fish&n
... Show More