Electromagnetic Polarizabilities and Charge Radii of the Nucleons in the Diquark-model

The diquark model is used to calculate the electromagnetic polarizabilities and charge radii of the nucleons for three different potentials. Making the scalar diquark lower in mass introduces a mixing angle $\theta$ between the $\left| 56\right\rangle$ and $\left| 70\right\rangle$ states ,which allows an improvement in value of all 6 properties. Generalizing the Gamov-Teller matrix and the magnetic moment operator to the diquark model gives constraints on this mixing. We obtain for the Richardson potential $\theta =23.2^{\circ },$ $\overline{\alpha }_p=7.9_{-0.9}^{+1.0}\times 10^{-4}fm^3,$ $\overline{\alpha }_n=7.7_{-0.6}^{+0.3}\times 10^{-4}fm^3,$ $\overline{\beta }_p=5.4_{-0.4}^{+1.6}\times 10^{-4}fm^3,$ $\overline{\beta }_n=6.7_{-0.7}^{+1.3}\times 10^{-4}fm^3,$ $\left\langle r^2\right\rangle _p=0.37_{-0.03}^{+0.02}fm^2,$ $\left\langle r^2\right\rangle _n=-0.07_{-0.02}^{+0.03}fm^2.$ Additional pion cloud contributions could improve on all six results.Comment: 15 Pages, Latex, Figs on request, to be published Phys.Lett.B. Minor errors corrected and eqn 5,6,8,9 correcte

DNA Display Selection of Peptide Ligands for a Full-Length Human G Protein-Coupled Receptor on CHO-K1 Cells

The G protein-coupled receptors (GPCRs), which form the largest group of transmembrane proteins involved in signal transduction, are major targets of currently available drugs. Thus, the search for cognate and surrogate peptide ligands for GPCRs is of both basic and therapeutic interest. Here we describe the application of an in vitro DNA display technology to screening libraries of peptide ligands for full-length GPCRs expressed on whole cells. We used human angiotensin II (Ang II) type-1 receptor (hAT1R) as a model GPCR. Under improved selection conditions using hAT1R-expressing Chinese hamster ovary (CHO)-K1 cells as bait, we confirmed that Ang II gene could be enriched more than 10,000-fold after four rounds of selection. Further, we successfully selected diverse Ang II-like peptides from randomized peptide libraries. The results provide more precise information on the sequence-function relationships of hAT1R ligands than can be obtained by conventional alanine-scanning mutagenesis. Completely in vitro DNA display can overcome the limitations of current display technologies and is expected to prove widely useful for screening diverse libraries of mutant peptide and protein ligands for receptors that can be expressed functionally on the surface of CHO-K1 cells

Asymmetric Regulation of Identical Polluters in Oligopoly Models

Studies of optimal second-best environmental regulation of identical polluting agents have invariably ignored potentially welfare-improving asymmetric regulation by imposing equal regulatory treatment of identical firms at the outset. Yet, cost asymmetry between oligopoly firms may well give rise to private as well as social gains. A trade-off is demonstrated for the regulator, between private costs savings and additional social costs when asymmetric treatment is allowed. Asymmetry is indeed optimal for a range of plausible parameter values. Further, it is demonstrated that for a broad class of abatement cost functions, there is scope for increasing welfare while keeping both total output and total emission constant. Some motivating policy issues are discussed in light of the results, including international harmonization and global carbon dioxide reduction. Copyright Springer 2005asymmetric emissions regulation, polluting oligopolists, EU harmonization,

Feather pecking in chickens is genetically related to behavioural and developmental traits

International audienc