Cat’s claw (Uncaria tomentosa) is a medicinal plant from the Amazon River basin that is widely used for inflammatory disorders and was previously described as an inhibitor of NF-kB. Cat’s claw was prepared as a decoction (water extraction) of micropulverized bark with and without concentration by freeze-drying. Murine macrophages (RAW 264.7 cells) were used in cytotoxicity assays (trypan blue e...

Ryjacek [Z. Ryjáček: On a closure concept in claw-free graphs. Journal of Combinatorial Theory Ser. B 70 (1997), 217-224] defined a powerful closure operation cl(G) on claw-free graphs G. Very recently, Ryjacek, Yoshimoto and the talker developed the closure operation cl (G) on claw-free graphs which preserves the (non)-existence of a 2-factor. In this talk, we introduce a closure operation cl(...

A graph G is 1-Hamilton-connected if G − x is Hamilton-connected for every vertex x ∈ V (G). In the paper we introduce a closure concept for 1-Hamiltonconnectedness in claw-free graphs. If G is a (new) closure of a claw-free graph G, then G is 1-Hamilton-connected if and only if G is 1-Hamilton-connected, G is the line graph of a multigraph, and for some x ∈ V (G), G − x is the line graph of a ...

We prove that claw-free graphs, containing an induced dominating path, have a Hamiltonian path, and that 2-connected claw-free graphs, containing an induced doubly dominating cycle or a pair of vertices such that there exist two internally disjoint induced dominating paths connecting them, have a Hamiltonian cycle. As a consequence, we obtain linear time algorithms for both problems if the inpu...

Claw trimming every four to six months has become a routine procedure for the majority of high yielding housed dairy cows. Various methods have been described, but the Dutch Five Step method (Toussaint Raven 1985) is probably the most widely used approach around the world and has been the basis for most research. Despite being the most commonly used protocol internationally, the Dutch Five Step...

Different levels of claw vacuum during machine milking may influence milking performance and teat condition. The claw vacuum acts on the teat and is responsible for removal and transport of milk but is also causing potential effects on the teat tissue. In the absence of milk flow, the claw vacuum is similar as the system vacuum. During milk flow, the claw vacuum drops to lower levels depending ...

We study some properties of the closure concept in claw-free graphs that was introduced by the rst author. It is known that G is hamiltonian if and only if its closure is hamiltonian, but, on the other hand, there are innnite classes of non-pancyclic graphs with pancyclic closure. We show several structural properties of claw-free graphs with complete closure and their clique cutsets and, using...

For s ≥ 3 a graph is K1,s-free if it does not contain an induced subgraph isomorphic to K1,s. Cycles in K1,3-free graphs, called clawfree graphs, have beenwell studied. In this paper we extend results on disjoint cycles in claw-free graphs satisfying certain minimum degree conditions to K1,s-free graphs, normally called generalized claw-free graphs. In particular, we prove that if G is K1,s-fre...

Let G be any graph and let c(G) denote the circumference of G. We conjecture that for every pair c1, c2 of positive integers satisfying c1 + c2 = c(G), the vertex set of G admits a partition into two sets V1 and V2, such that Vi induces a graph of circumference at most ci , i = 1, 2. We establish various results in support of the conjecture; e.g. it is observed that planar graphs, claw-free gra...

A graph is claw-free if it does not contain K I ,3 as an induced subgraph. A graph is KI,r-free if it does not contain KI,r as an induced subgraph. In this paper, we find bounds on the minimum number of edges needed to ensure a KI,.,.-free contains k vertex disjoint cycles. The bound on claw-free graphs is sharp.