On the stable set polytope of a series-parallel graph

We give a short proof of Chvátal's conjecture that the nontrivial facets of the stable set polytope of a series-parallel graph all come from edges and odd holes.Research supported in part by the Natural Sciences and Engineering Research Council of Canada and by CP Rail.     

Deficiency zero non-metacyclicp-groups of order less than 1000

There are 49 non-metacyclicp-groups of order less than 1000 with trivial Schur multiplier. In this papar we give a list of deficiency zero presentations for these groups.     

Zeolite-catalyzed synthesis of pyrazolo[1,2-<Emphasis Type="Italic">a</Emphasis>][1,2,4]triazole-1,3-dione derivatives as anti-breast cancer agents

A series of pyrazolo[1,2-a][1,2,4]triazole-1,3-dione derivatives were synthesized under the catalytic effect of Natrolite zeolite, and their cytotoxic effects on three human breast cancer cell lines viz. breast cancer (BT-474), triple negative breast cancer (MDA-MB 231), and breast carcinoma (MCF-7) were explored using MTT assay. Apoptotic effects of the compounds were investigated by western blot analysis on the caspase-3 protein. Moreover, we examined the level of reactive oxygen species in all three cell lines. The most promising compound, 7-Amino-1,3-dioxo-5-(4-nitrophenyl)-2-phenyl-1,2,3-trihydropyrazolo[1,2-a][1,2,4]triazole-6-carbonitrile (4c), showed high levels of cytotoxicity against all cell lines with IC₅₀ values of 2.3, 2.5 and 3 μg/ml, respectively.     

Structure Functions in Complex Flows

The turbulence in the ocean and atmosphere is most of the time non-homogeneous in nature. These spatial changes could affect the structure of the turbulence. In this work a classification is proposed to determine the intermittency and mixing ability. The variation of the structure functions and the scaling exponent in decaying non-homogeneous turbulence produced by a grid and by a jet is measured with a sonic velocimeter SONTEK3-D. We use Extended Self Similarity (ESS) to obtain better estimates of the scaling exponents of the structure functions of order up to the 6th. We study the variation of the absolute scaling exponents _p and relative scaling exponents ¯_p as a function of distance from the source of turbulence. In most cases, the absolute scaling exponent ₃ is shown to vary as function of the separation distance l. On the other hand the relative scaling exponents ¯_p depend on the location of the flow and in most cases the deviations from the Kolmogorov 1941 scaling are related to the intermittency.     

Oxidative amidation of benzyl alcohol,benzaldhyde, benzoic acid styrene and phenyl acetylene catalyzed by ordered mesoporous HKUST‐1‐Cu: Effect of surface area on oxidative amidation reaction

HKUST‐1‐Cu synthesized in the presence and absence of P‐123 trough solvotermal method. After characterization using some different microscopic and spectroscopic techniques such as XRD, FT‐IR, SEM, ICP, BET and TEM its catalytic activity was investigated in the oxidative coupling of benzyl alcohol, benzaldhyde, benzoic acid, styrene and phenyl acetylene with N,N‐dialkylformamides for the preparation of N,N‐dimethylformamides. Different derivatives of tertiary amides were synthesized in moderate to good yields in the presence of just ~0.28 mol% of this catalytic system. Reusability of the synthesized catalysts was examined and catalysts were reusable for 8 times without significant decrease in optimized conditions.     

Mutagenic, antimutagenic and antioxidant activities of a new polyphenolic and a flavonoid substances isolated from Anagallis monelli

A new polyphenolic natural substance: 2,5-dihydroxy-benzoic acid 3'-formyl-5'-hydroxy-phenyl ester (1), Anamighrinal and 3-(O-alpha-L-rhamnosyl) quercetin (2) have been isolated from the methanolic aerial part extract of the plant Anagallis monelli by chromatographic separation. Their structures have been deduced essentially by one and two NMR spectroscopic procedures and mass spectrometry. Antioxidant, mutagenic, antimutagenic activities, of the natural products were realised and positive results were recorded.