Two predators, one prey model that integrates the effect of supplementary food resources due to one predator's kleptoparasitism under the possibility of retribution by the other predator.

In ecology, foraging requires animals to expend energy in order to obtain resources. The cost of foraging can be reduced through kleptoparasitism, the theft of a resource that another individual has expended effort to acquire. Thus, kleptoparasitism is one of the most significant feeding techniques in ecology. The phenomenon of kleptoparasitism has garnered significant attention from scholars due to its substantial impact on the food chain. However, the proportionate amount of mathematical modelling to facilitate the analysis has made limited progress in the literature. This circumstance motivated us to develop mathematical models that could explain the population dynamics of the prey-predator food chain. This study explores a scenario with two predators and one prey, where one predator is a kleptoparasite and the other is a host. The energy depletion caused by the predator's counterattack subsequent to kleptoparasitism, notwithstanding the nonlethal nature of this antagonism, is an additional component incorporated into this model. It has been suggested that biologically viable equilibria must meet certain parametric conditions in order to exist and to be stable both locally and globally. This article delves deeply into the occurrences of various one-parametric bifurcations, such as saddle-node bifurcation, transcritical bifurcation, and Hopf bifurcation, as well as two-parametric bifurcations, such as Bautin bifurcation. A subcritical Hopf bifurcation happens when the growth rate of the first predator is relatively low, while a supercritical Hopf bifurcation occurs when the growth rate of the first predator is quite large, allowing for the coexistence of all three species. Numerical simulations have been conducted to validate our theoretical findings.

Stage structured prey-predator model incorporating mortal peril consequential to inefficiency and habitat complexity in juvenile hunting.

Dynamic exploration for a predator-prey biosystem of two species with ratio-dependent functional response together with the capability for predation by both juvenile and adult stage of the predator is carried out; coupled with incentive from all the natural documentation acquainting habitat complexity as an armour for the prey and also as a factor effectuating mortality of only the juvenile predators, attributable to their inefficiency. So as to avoid extinction of either of the species and to preserve the food chain of the ecological system, the results pertaining to the existence and stability of all the equilibrium points of the biosystem along with permanence, transcritical and Hopf bifurcation have been thoroughly studied. Excessive predation by juveniles exhibits destabilization of the biosystem through supercritical Hopf bifurcation; likewise, minimal inefficiency of juveniles and habitat complexity spawns extinction and fluctuation of each species, contrarily an abundance of them decimates the predator species. The obtained results and the dependence of the biosystem on some vital parameters are corroborated from a biological viewpoint, through numerical simulation, for implementation of the system in real-life scenario. Interestingly, an illustration reveals an intriguing limit cycle between the proposed system's trivial and axial equilibriums of the proposed system along with the co-existing periodic point for specific parametric values of inefficiency of juvenile predators.

Microscopic Studies on Erythrocytes of Channa punctata Exposed to Commercial Grade Lindane

ABSTRACT Light and scanning electron microscopic studies of erythrocytes of Channa punctata exposed to two sublethal doses of lindane over a period of 21 days revealed myriads of anomalies. High frequency of micronucleus appeared progressively in the erythrocyte, ranging from 3.8-7.5%, when monitored weekly for 21 d at 0.25 g/L and 1.0-3.0% at 0.025 g/L lindane. Prominent structural anomalies of erythrocytes included abnormal shapes, vacuolation, membrane invagination and disintegration. At higher dose and at later duration, a unique tendency of abnormal cells to stick together was observed. It could be concluded that commercial formulation of lindane could induce genotoxicity and structural anomalies in the erythrocytes of fish.

Primary extramedullary plasmacytoma of ovary: Report of a rare neoplasm.

Primary extramedullary plasmacytoma is a rare plasma cell neoplasm. Extramedullary plasmacytomas are most commonly found in head and neck region, but it can occur at other sites occasionally. Involvement of ovary by this tumor is exceedingly rare. Here, we report a case of primary ovarian plasmacytoma in a 47-year-old woman. The patient presented with a lower abdominal pain and a left ovarian mass (12 cm × 10 cm) was detected during the ultrasonographic examination. The patient underwent hysterectomy with bilateral salpingo-oophorectomy. Subsequent histopathologic, immunohistochemistry, bone marrow examination, and other relevant examinations established the diagnosis of primary ovarian plasmacytoma. The patient did not receive the postoperative chemotherapy and 6 months follow-up was uneventful.