in this paper we study the dynamics of hepatitis b virus (hbv) infection under administration of a vaccine and treatment, where the disease is transmitted directly from the parents to the offspring  and also through contact with infective individuals. stability of the disease-free steady state is investigated. the basic reproductive rate, $r_0$, is derived. the results show that the dynamics of...

The Lifetime Reproductive Success (LRS) of an individual i.e. the number of young raised during its lifespan is an indicator of its contribution to future generations and thus a measure of fitness. Nevertheless, the LRS is hard to estimate because of the difficulty to keep track of the outcome of each breeding attempt (successful or failed and, if successful, number of young raised). We propose...

the purpose of this research was the study of reproductive performance in postpartum dairy cows with different parities. twenty holstein dairy cows were assigned into two equal primiparous and multiparous groups. body weight and body condition score (based on 1-5 scoring) were measured every other week, starting from two weeks before calving till pregnancy confirmation. daily milk yield was als...

The study was conducted at Ardaita Agricultural Technical Vocational Education Training (ATVET) college dairy farm, to evaluate the reproductive performance of Holstein Friesian and its crosses with Boran cattle breeds. Data collected between 2000 and 2015 on reproductive traits (n=2632) were studied and analyzed using general linear model procedure. The overall estimated means for age at first...

in order to investigate drought stress and plant density the yield, yield components and protein of spotted bean grain (cultivar talash), an experiment was carried out as split plots in randomized complete blocks with three replications in yasouj, in 2012. factors of the test including irrigation in three levels; without stress (control treatment), water stress in vegetative stage (interrupting...

We show the erroneous assumptions and reasoning by introducing the migration effect of individuals in the transmission model of Hepatitis B virus. First, some false results related to the eigenvalues and reproductive number in the recent literature in mathematical biology will be presented. Then, it will be proved that the product of the matrices in the next generation method to obtain the repr...

Haplodiploidy results in relatedness asymmetries between colony members of highly eusocial Hymenoptera. As a consequence, queen and reproductive workers are more related to their own sons than to each other's male offspring. Kin selection theory predicts multiple optima in male parentage: either the queen or the workers should produce all the males. Nevertheless, shared male parentage is common...

anise hyssop is a prennial herb belonging to the lamiaceae family. essential oil of this plant is used in food, pharmaceuticals, cosmetics industries as well as flavoring liqueurs. since water stress affects the growth, productivity, as well influences the active principles governing medicinal plants, in this research the effect of different water deficit stresses on such morphological traits a...

The reproductive cycle, size/fecundity relationships and seasonality in the reproduction of the poeciliid Phallocerus caudimaculatus were studied in Southeastern Brazil. There was a positive correlation between the monthly proportion of females with offspring and the day length and between female’s size and offspring number. The reproductive period starts in November, when most of the females c...

An SIS/SAS model of gonorrhea transmission in a men-seeking-men (MSM) system is presented in this paper to study the impact of education on the dynamics of gonorrhea prevalence. Education affects behaviors that may fall into two categories– prevention and disease status awareness. Stability conditions for the disease free equilibrium and endemic equilibrium are determined along with an analytic...