Let $G$ be a connected graph of order $n$ and minimum degree $delta(G)$.The edge-connectivity $lambda(G)$ of $G$ is the minimum numberof edges whose removal renders $G$ disconnected. It is well-known that$lambda(G) leq delta(G)$,and if $lambda(G)=delta(G)$, then$G$ is said to be maximally edge-connected. A classical resultby Chartrand gives the sufficient condition $delta(G) geq frac{n-1}{2}$fo...

_______________________________________________________________________________________________________________ 1. Associated Professor of Emergency Medicine, Iran University of Medical Sciences, Tehran, Iran. [email protected] 2. Associated Professor of Emergency Medicine, Iran University of Medical Sciences, Tehran, Iran. [email protected] 3. Assistant Professor of Emergency Medicin...

in order to determine the resistance levels and the most suitable potato genotypes to the early blight, an experiment was conducted in a completely randomized factorial design with three replications, in national plant gene bank of iran during 2007-2008. factors included pathogenic fungus, a. tenuissima and a. alternata and six potato genotypes, picasso, marfona, delta, agria, cosmos and armida...

In this paper we prove that any distance-balanced graph $G$ with $Delta(G)geq |V(G)|-3$ is regular. Also we define notion of distance-balanced closure of a graph and we find distance-balanced closures of trees $T$ with $Delta(T)geq |V(T)|-3$.

1Department of Physiology, Faculty of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran 2Faculty of Veterinary Science, Shahrekord Islamic Azad University, Shahrekord, Iran 3Department of Medical Genetics, Shahid Beheshti University of Medical Sciences, Tehran, Iran 4Department of Biochemistry, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran 5Departmen...

a proper vertex coloring of a simple graph is $k$-forested if the graph induced by the vertices of any two color classes is a forest with maximum degree less than $k$. a graph is $k$-forested $q$-choosable if for a given list of $q$ colors associated with each vertex $v$, there exists a $k$-forested coloring of $g$ such that each vertex receives a color from its own list. in this paper, we prov...

let $alpha$ be an endomorphism and $delta$ an $alpha$-derivationof a ring $r$.  in this paper we  study the relationship between an$r$-module $m_r$ and the  general polynomial module  $m[x]$ over theskew polynomial ring $r[x;alpha,delta]$. we introduce the notionsof skew-armendariz modules and skew quasi-armendariz modules whichare generalizations of $alpha$-armendariz modules and extend thecla...

1Department of Cardiac Anesthesiology, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, IR Iran 2Department of Cardiac Surgery, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, IR Iran 3Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, IR Iran 4Shahid Behes...

The average distance of a vertex $v$ of a connected graph $G$is the arithmetic mean of the distances from $v$ to allother vertices of $G$. The proximity $pi(G)$ and the remoteness $rho(G)$of $G$ are defined as the minimum and maximum averagedistance of the vertices of $G$. In this paper we investigate the difference between proximity or remoteness and the classical distanceparameters diameter a...