Mathematical models are proposed to simulate migrations of prey and predators between patches. In the absence of predators, it is shown that the adaptation of prey leads to an ideal spatial distribution in the sense that the maximal capacity of each patch is achieved. With the introduction of co-adaptation of predators, it is proved that both prey and predators achieve ideal spatial distributio...

The literature posits that an introduced predator population, is able to drive it's target pest population extinct, if supplemented with high quality additional food of quantity $\xi > \xi_{critical}$, \cite{SP11, SPV18, SPD17, SPM13}. We show this approach leads infinite time blow-up the population. propose alternate model in which induces competition. Analysis herein indicates there are thres...

background: toxoplasma gondii is one of the most prevalent parasites of human and warm- blooded animals. toxoplasmosis is important especially in two groups: pregnant women and immunocompromised patients. if women acquire the primary infection during the pregnancy, it would be life threatening or re-mains severe disorders for the fetus. this study was performed to evaluate the seroprevalence of...

in order to achieve high quality seeds, producers must be able to estimate the accurate harvest maturity time seeds. the objective of this study was to investigate changes in seed quality during seed development and maturation in the two cultivars native of the sari and gorgan and two cultivars modified of the darab14 and yellowhite. a field experiment was conducted in during 2009 at gorgan uni...