in this study, the role of soil properties in making difference between plant communitieswas examined. first, four plant types were identified, including pteropyrumaucheri-salsolarigida، astragalus gossypinus - acanthophyllum herateens، amygdalus scoparia – achilla millefolium and ephedra intermedia – erigon capestra, through randomized systematic sampling and field survey in representative are...

Cyanophages (viruses that infect cyanobacteria) are abundant in the marine environment and are thought to be a significant factor in determining the population dynamics of members of the unicellular phycoerythrin-containing cyanobacteria of the genus Synechococcus. In an effort to use molecular techniques to characterise cyanophage populations, a conserved region from the cyanophage genome was ...

Assessment and monitoring of rangeland in different grazing managements seems necessary to manage rangelands. The plant functional groups can be used as appropriate responders for rangelands condition and management. Therefore, this study was performed and aimed to determine the most important traits that are influenced by rangeland variation and management. In order to this, three areas along ...

Previous work on sample design has been focused on constructing designs for samples taken at point locations. Significantly less work has been done on sample design for data collected along transects. A review of approaches to point and transect sampling design shows that transects can be considered as a sequential set of point samples. Any two sampling designs can be compared through using eac...

We construct a polynomial-time algorithm to approximate the branch-width of certain symmetric submodular functions, and give two applications. The first is to graph “clique-width”. Clique-width is a measure of the difficulty of decomposing a graph in a kind of tree-structure, and if a graph has clique-width at most k then the corresponding decomposition of the graph is called a “k-expression”. ...

There are several reasons why this book might be of interest to a TEX user. First, LTEX has a prominent place in the book. Second, the book describes a very interesting offshoot of literate programming, a topic traditionally popular in the TEX community. Third, since a number of TEX users work with data analysis and statistics, R could be a useful tool for them. Since some TUGboat readers are l...