A FLUORESCENCE LIFETIME ASSAY OF A MEMBRANE-BOUND FLAVIN FROM CORN COLEOPTILES

Abstract— The fluorescence lifetime of a partially-purified membrane fraction containing flavin and b-type cytochrome, presumably on the same protein, has been described. Possible implications of the blue light photoreactivity of the flavin as an assay, on the basis of its short fluorescence lifetime (about 1.37 ns), has been discussed.     

Optimizing the degradation of dichlorvos in aqueous solution using nZVI DTPA+H2O2 and its detection using ac conductivity measurement with the help of response surface methodology

Degradation of organic pollutants in wastewater is a common subject of discussion under advanced oxidation process. To detect the degradation of colourless organic pollutants conventional analytical techniques are available but their sophistication makes it difficult to pursue in all form of chemical laboratories. In the present study it was found that during degradation of Dichlorvos using diethylene triamine pent acetic acid (DTPA) stabilized nano zero valent iron (nZVI), COD removal and ac conductivity change has been done simultaneously. In this degradation study the heterogeneous Fenton type oxidation method was employed and an LCR circuit (which contains inductor, capacitor and resistor) was used to measure the ac conductivity. This study aims to find out a correlation between ac conductivity and COD removal using simple response surface methodology (RSM) so that the degradation of colourless pollutants can be estimated easily and also to identify the best processing parameters to optimise Dichlorvos degradation. It was found that COD removal in most of all cases, was more than 60% when the change in final ac conductivity more than 600% with respect to initial value. All of the experimental results were in good accord with the projected outcome.     

P-positions in modular extensions to Nim

In this paper, we consider a modular extension to the game of Nim, which we call m-Modular Nim, and explore its optimal strategy. In m-Modular Nim, a player can either make a standard Nim move or remove a multiple of m tokens in total. We develop a winning strategy for all m with 2 heaps and for odd m with any number of heaps.     

Cell antigens recognized by rabbit antibodies specific for oligomannosyl determinants.

Rabbit antibodies to cell wall mannans of various microbial strains and their mutants were found to be cross-reactive to cell carbohydrates of mammalian sperm and 4-6-days-old blastocysts. Immunochemical studies indicate that oligomers of alpha1 yields to 2, alpha1 yields to 3, alpha1 yields to 6, and probably also alpha yields to 4 linked mannose residues of sperm carbohydrates are available for antibody binding. At least 80 percent of binding activity of a yeast mannan antibody to sperm can be effectively inhibited by specific haptens or digestion with exo-alpha-D-mannosidase, an enzyme activity highest in testicular tissue. In order to determine the role of this enzyme in the metabolism of the cross-reactive mannan antigens of sperm, the relative amount of a specific alpha-linked oligomannosyl determinant of bovine sperm from homozygous normals was compared to that of hetero-zygous carriers of alpha-mannosidase deficiency. Extensive cross-reactivity between the microbial and mammalian oligomannosyl determinants suggest that these are conserved structures in cell carbohydrates, although the organization of these units in the microbial cell wall lipopolysaccharide has very little similarity to the carbohydrate moieties of mammalian glycoproteins.     

Probing the exotic particle content beyond the standard model

We explore the possible exotic particle content beyond the standard model by examining all its scalar bilinear combinations. We categorize these exotic scalar fields and show that without the suppression of (A) their Yukawa couplings with the known quarks and leptons, and (B) the trilinear couplings among themselves, most are already constrained to be very heavy from the nonobservation of proton decay and neutron-antineutron oscillations, the smallness of , and mixing, as well as the requirement of a nonzero baryon asymmetry of the universe. On the other hand, assumption (B) may be naturally violated in many models, especially in supersymmetry, hence certain exotic scalars are allowed to be below a few TeV in mass and would be easily detectable at planned future hadron colliders. In particular, large cross sections for the distinctive processes like and would be expected at the Fermilab Tevatron and CERN LHC, respectively. Received: 1 September 1998 / Revised version: 15 October 1998 / Published online: 22 March 1999     

Tunneling dynamics of one- and two-dimensional cubic oscillators with randomly fluctuating harmonic force constants: A numerical experiment

The tunneling dynamics of one- and two-dimensional cubic oscillators having randomly fluctuating harmonic force constants (K_t) are studied numerically by invoking the time-dependent Fourier grid Hamiltonian method. The influence of the frequency and strength of the fluctuation on the tunneling probability and tunneling rate is analyzed. The predicted nature of the influence depends upon whether the cubic oscillator is one- or two-dimensional. The possibility of mapping the proton-transfer systems onto the present model is explored. © 1997 John Wiley & Sons, Inc. Int J Quant Chem 64 : 403–409, 1997