A Geometric Invariant for Metabelian Pro-p Groups

In [2] Bieri and Strebel introduced a geometric invariant forfinitely generated abstract metabelian groups that determineswhich groups are finitely presented. For a valuable survey oftheir results, see [6]; we recall the definition briefly inSection 4. We shall introduce a similar invariant for pro-pgroups. Let F be the algebraic closure of F_p and U be the formal powerseries algebra F[T], with group of units U^x. Let Q be a finitelygenerated abelian pro-p group. We write Z_p[Q] for the completedgroup algebra of Q over Z_p. Let T(Q) be the abelian group Hom(Q,U^x) of continuous homomorphisms from Q to U^x. We write 1 forthe trivial homomorphism. Each vT(Q) extends to a unique continuousalgebra homomorphism from Z_p[Q]to U.     

Cross section and stellar reaction rates for the 42Ca(p, γ) reaction

The cross section for the ⁴²Ca(p, γ)⁴³Sc reaction has been measured over the lab energy range from 0.7 to 5.5 MeV using a positron spectrometer to measure the annihilation radiation from the decay of 3.9 h ⁴³Sc. Stellar reaction rates N_A〈σv〉 have been calculated from the experimental cross section curve for a series of three temperatures of interest for explosive oxygen and silicon burning in stars. The calculated rates are compared with the theoretical predictions of Woosley et al. and found to be in agreement within the experimental errors and the quoted validity of the theoretical calculation     

The use of electron impact dissociation and the photon-photon cascade technique to measure the lifetime of the B2Σ+ state of CN

The lifetime of the (B³Σ⁺_{υ= 0, 1} state of the CN radical has been measured by the photon-photon delayed coincidence technique, the CN radical being produced by electron impact dissociation of acetonitrile. This is the first lifetime measurement in a free radical by this method. The optical cascade in the band spectrum of CN used for the present measurement is H²Π_r - B²Σ⁺ - X²Σ⁺. The lifetime of the (B²Σ⁺)_{υ=0, 1} state in CN has been found to be 61.1 ± 7.6 ns.     

Study on Antitumor Plant Gymnosporia Trilocularis

The alcoholic extract of Gymnosporia trilocularis Hay. (Celastraceae) was found to exhibit antitumor activities against P388 lymphocytic leukemia and KB cell culture systems. From this extract β-amyrin ( 1 ), β-sitosterol ( 2 ) and its monoglucoside ( 6 ), stigmasterol ( 3 ) and its monoglucoside ( 7 ), campesterol ( 4 ) and its monoglucoside ( 8 ), maniladiol ( 5 ), dulcitol ( 9 ) and six yet unidentified principles ( 10–15 ) were isolated. The stereochemistry of C-16-OH of maniladiol ( 5 ) was confirmed spectroscopically by ¹H nmr to be equatorial. Of all the isolated compounds, the mixture of three steroid monoglucosides ( 6:7:8 =28:1.1:1) exhibited cytotoxicity (ED₅₀=2.6×10⁰ mcg/ml) and 5 showed only marginal effect (ED₅₀=2.1×10¹ mcg/ml) in KB test system.