The tenacity of a graph G, T(G), is dened by T(G) = min{[|S|+τ(G-S)]/[ω(G-S)]}, where the minimum is taken over all vertex cutsets S of G. We dene τ(G - S) to be the number of the vertices in the largest component of the graph G - S, and ω(G - S) be the number of components of G - S.In this paper a lower bound for the tenacity T(G) of a graph with genus γ(G) is obtained using the graph's connec...

The genus Calendula belongs to tribe Calenduleae, (Asteraceae family). Itmorphologically studied for the ongoing project of the flora of Iran. Based on the herbarium studies and field observation, this genus has been revised. The study was based on fresh material from field as well as herbarium specimens. All specimens existed in the herbarium of Research Institute of...

tick are considered as the main vector for transmission of various diseases to human being. this study was carried out to investigate the fauna of species belonging to two families of ticks, ixodidae and argasidae in west azerbaijan province, iran. a total number of 62 villages were selected randomly, from the study area 3278 ticks were collected with cluster sampling method, after collection t...

the brush-tailed mice of the genus calomyscus are distributed in the mountains of central asia and the middle east. the genus calomyscus represents five nominate species from iran (c. bailwardi, c. grandis, c. hotsoni, c. urartensis and c. elburzensis). in total 64 specimens from four species of calomyscus were studied for morphometric analyses the morphological differences among 10 populations...

In this study frequency and composition of plankton in Shadegan wetland was carried out in 5 stations during 2007-2008. Genus qualitative identification and their composition and quantitative frequency aspect were studied (for phytoplankton chlorophyll a). Frequency of total 42 genus phytoplankton in 4 classes Bacilariophyceae (Diatom), Cyanophyceae, Chlorophyceae and Dinophyceae are 69.4, 22.2...

the genus campylobacter  is of great importance to public health because it includes several species that may cause diarrhoea. poultry and poultry products are known as important sources of human campylobacteriosis. in this study, during the autumn months of 2005, a total of 100 samples from poultry carcasses, representing 20 broiler flocks were obtained by rinse test, after the chilling stage ...

the coniferae which are propolis sources in iran i- pinaceae   hassan nazarian* *imam khomeini higher education center, agricultural research, education and extension organization e.mail: [email protected]   abstract the coniferae are from important propolis sources of iran. pinaceae have a particular importance in this taxon. all species of this family do not have any natural distribution ...