منابع مشابه
On computing the general Narumi-Katayama index of some graphs
The Narumi-Katayama index was the first topological index defined by the product of some graph theoretical quantities. Let $G$ be a simple graph with vertex set $V = {v_1,ldots, v_n }$ and $d(v)$ be the degree of vertex $v$ in the graph $G$. The Narumi-Katayama index is defined as $NK(G) = prod_{vin V}d(v)$. In this paper, the Narumi-Katayama index is generalized using a $n$-ve...
متن کاملSome new bounds on the general sum--connectivity index
Let $G=(V,E)$ be a simple connectedgraph with $n$ vertices, $m$ edges and sequence of vertex degrees$d_1 ge d_2 ge cdots ge d_n>0$, $d_i=d(v_i)$, where $v_iin V$. With $isim j$ we denote adjacency ofvertices $v_i$ and $v_j$. The generalsum--connectivity index of graph is defined as $chi_{alpha}(G)=sum_{isim j}(d_i+d_j)^{alpha}$, where $alpha$ is an arbitrary real<b...
متن کاملOn the lower and upper bounds for general Randić index of chemical (n,m)-graphs
A chemical (n,m)-graph is a connected graph of order n, size m and maximum degree at most 4. The general Randić index of a graph is defined as the sum of the weights [d(u)d(v)]α of all edges uv of the graph, where α is any real number and d(u) is the degree of a vertex u. In this paper, we give the lower and upper bounds for general Randić index of chemical (n,m)-graphs. A graph of order n and ...
متن کاملmesuring the staff technology readiness, the case of a multi national chemical company operating in iran
چکیده ندارد.
15 صفحه اولPI3K At The Clinical Crossroads | Cover Story | Chemical & Engineering News
PI3 kinases are obvious targets for researchers developing cancer drugs. Formally known as phosphatidylinositol-3 kinases, the enzymes are involved in a laundry list of functions that contribute to the ability of cells to thrive. By adding a phosphate to signaling molecules, they set off a chain reaction that can lead to protein synthesis, cell survival, cell migration, and blood vessel growth....
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Nature
سال: 1913
ISSN: 0028-0836,1476-4687
DOI: 10.1038/091394a0