the spotted toad-headed agama, phrynocephalus maculatus, is a member of the agamidae family distributed in the central and south-eastern deserts of iran. iranian specimens are rare in collections. in this research, the female reproductive cycle of this species was studied from april 5 to august 5, 2013. totally, 15 adult females were collected by hand at midday from southern parts of damghan co...

The aim of this investigation was to study macroscopic and microscopic structures of ovaries in Barbus grypus of Karoon river and their changes during annual maturation cycle. For this purpose, 120 adult  B.grypus with a mean weight of 835.0 to 1012.0 g, were caught from Karoon river and transferred alive to the laboratory. After biometrical studies, the weights and morphological appearances of...

Understanding latitudinal variation in avian life-history traits has been a focus of many demographic studies around the world. However, we still know little about annual or intra-annual demographic variation within tropical regions or about how factors such as breeding season and precipitation influence demographic rates. In this study, we estimated intra-annual apparent survival of the White-...

Over the last century the reproduction of sturgeon has been intensively studied par Russian scientists who established a technology for the ranching of alevins which included artificial fertilization of gametes taken from wild broodfish and larvae rearing. More recently, since 1970, major contributions originated from teams in the USA, the EU, Japan and Iran. A rather good knowledge of the repr...

Over the last century the reproduction of sturgeon has been intensively studied par Russian scientists who established a technology for the ranching of alevins which included artificial fertilization of gametes taken from wild broodfish and larvae rearing. More recently, since 1970, major contributions originated from teams in the USA, the EU, Japan and Iran. A rather good knowledge of the repr...

The purple dye murex Bolinus brandaris is a commercially valuable gastropod in Portugal. However, there is a lack of knowledge on the reproductive cycle in Atlantic populations of this species. In this context, the reproductive cycle of B. brandaris from the Ria Formosa lagoon, southern Portugal, was studied using standard histology and light microscopy and the calculation of bio-physiological ...

The annual oviductal cycle of the Cottonmouth, Agkistrodon piscivorus, is described using electron microscopy. This is only the second such study on a snake and the first on a viperid species. Specimens were collected in reproductive and nonreproductive condition throughout the year and five ultrastructurally unique regions were recognized: the anterior infundibulum, posterior infundibulum, gla...

In this paper, the annual and economic performance of an integrated solar combined cycle (ISCC) with indirect energy storage tanks is investigated. The study includes four scenarios, in which the combined cycle performance was studied exclusively in the first scenario. In the second scenario, the integrated solar combined cycle (ISCC) was examined, and the use of supplementary firing instead of...

The study of sexual selection has traditionally focused on events and behaviours immediately surrounding copulation. In this study, we examine whether carry-over effects from the non-breeding season can influence the process of sexual selection in a long-distance migratory bird, the American redstart (Setophaga ruticilla). Previous work on American redstarts demonstrated that overwintering in a...

Acid phosphatase (AcP) activity was investigated in the testes of two species of teleosts in two seasons: summer and winter. AcP activity was detected in Sertoli cells from tilapia (Oreochromis niloticus) only during the nonreproductive period of its annual cycle, corresponding to the winter months. In kingfish (Odonthestes perugiae), the enzymatic reaction was identified during the non-reprodu...