Branching ratio measurements of the 7.12-MeV state in 16O

Knowledge of the gamma-ray branching ratios of the 7.12-MeV state of 16O is important for the extrapolation of the 12C(a,g)16O cross section to astrophysical energies. Ground state transitions provide most of the 12C(a,g)16O total cross section while cascade transitions have contributions of the order of 10-20%. Determining the 7.12-MeV branching ratio will result in a better extrapolation of the cascade and E2 ground state cross section to low energies. We report here on measurements on the branching ratio of the 7.12-MeV level in 16O.Comment: 4 pages, 5 figures. Contribution to the Eigth International Symposium on Nuclei in the Cosmo

Comparative analysis of 18S rRNA genes from Myxobolus aeglefini Auerbach, 1906 isolated from cod (Gadus morhua), Plaice (Pleuronectes platessa) and dab (Limanda limanda), using PCR-RFLP

The myxosporean parasite Myxobolus aeglefini is a marine species, which can be found in the cartilage of mainly gadid fish species. The parasite has, however, been recorded in the flatfish plaice (Pleuronectes platessa) and dab (Limanda limanda). It is not clear if isolates from unrelated hosts represent the same species. Therefore a molecular study was conducted to reveal differences at the DNA level between these isolates. PCR was successfully conducted on three different isolates of Myxobolus aeglefini sampled from cod (Gadus morhua), plaice and dab respectively, using 18S rDNA as template. A PCR product of approx. 1600 base pairs was obtained and RFLP (Restriction Fragment Length Polymerase) was conducted on the fragment with the restriction enzymes Hinf I, Msp I and Hae III. No differences between the isolates were found, suggesting that the three isolates represent the same species

Intrinsic quadrupole moment of the nucleon

We address the question of the intrinsic quadrupole moment Q_0 of the nucleon in various models. All models give a positive intrinsic quadrupole moment for the proton. This corresponds to a prolate deformation. We also calculate the intrinsic quadrupole moment of the Delta(1232). All our models lead to a negative intrinsic quadrupole moment of the Delta corresponding to an oblate deformation.Comment: 17 pages, 5 figure

Analysis of the total 12C(α,γ)16O cross section based on available angular distributions and other primary data

Because a knowledge of the 12C/16O ratio is crucial to the understanding of the later evolution of massive stars, new R- and K-matrix fits have been completed using the available angular distribution data from radiative α capture and elastic α scattering on 12C. Estimates of the total 12C(α,γ)16O rate at stellar energies are reported. In contrast with previous work, the analyses generally involve R- and K-matrix fits directly to the primary data, i.e., the energy- and angle-dependent differential yields, with all relevant partial waves fitted simultaneously (referred to here as surface fits). It is shown that, while the E1 part of the reaction is well constrained by a recent experiment on the β-delayed α-particle decay of 16N, only upper limits can be placed on the E2 ground state cross section factor which we take conservatively as SE2(300)<140 keV b. Simulations were then carried out to explore what kind of new data could lead to better restrictions on SE2(300). We find that improved elastic scattering data may be the best short-term candidate for such restrictions while significantly improving S(300) with new radiative capture data may require a longer-term effort. Theoretical models and estimates from α-transfer reactions for the E2 part of 12C(α,γ)16O are then discussed for comparison with the R- and K-matrix fits of the present work

Intrinsically Legal-For-Trade Objects by Digital Signatures

The established techniques for legal-for-trade registration of weight values meet the legal requirements, but in praxis they show serious disadvantages. We report on the first implementation of intrinsically legal-for-trade objects, namely weight values signed by the scale, that is accepted by the approval authority. The strict requirements from both the approval- and the verification-authority as well as the limitations due to the hardware of the scale were a special challenge. The presented solution fulfills all legal requirements and eliminates the existing practical disadvantages.Comment: 4 pages, 0 figure

Excited nucleon electromagnetic form factors from broken spin-flavor symmetry

A group theoretical derivation of a relation between the N --> Delta charge quadrupole transition and neutron charge form factors is presented.Comment: 4 pages, Proc. of the 12 th Int'l. Workshop on the Physics of Excited Nucleons, NSTAR 2009, Beijing, April 19-22, 200

Particle image velocimetry measurements of blood flow in a modeled carotid artery bifurcation

Cardiovascular diseases are on of the leading causes of mortality and morbidity in the western world. Amongst these diseases, atherosclerosis, a progressive narrowing of the arterial wall is one of the most severe and if untreated may lead to stroke or ischemic infarction. Fluid mechanic forces are a key player in the early development and progression of atherosclerosis and a better understanding of the interplay between haemodynamic and vascular diseases is needed. The carotid artery (CA) in one of the predominant sites of atherosclerotic plaque formation. In this work a transparent, scaled model of an average human carotid artery (AHCA) bifurcation was constructed and steady blood flow at Re = 290 and Re = 700 was simulated using an aqueous glycerin solution. Particle Image Velocimetry (PIV) measurements were performed in the plane of bifurcation and three axial planes in the carotid sinus. Flow inside the CA bifurcation was found to be three-dimensional with strong secondary currents due to the curvature of the vessel. An accurate method for wall shear stress (WSS) calculation along the outer internal carotid artery (ICA) wall is introduced. The method was tested against synthetically generated particle images and was found to perform best for an 8x8 pix2 interrogation windows. A large low momentum flow region with low WSS along the outer ICA wall exists, posing the potential for atherosclerotic plaque formation. Calculated WSS ranged between 0 and 21. Pa and compared well with in-vivo data

Some remarks concerning the complexity of computing class groups of quadratic fields

AbstractLet O be an order of any quadratic number field. In this paper we show that under the assumption of the generalized Riemann hypothesis the following decision problems are in NP ⊃ co-NP: 1.1. Is a given ideal A of O principal?2.2. Given ideals A1, … , Aκ of O, do their equivalence classes generate the class group of O?3.3. Given ideals A1, … , Aκ of O, is the class group of O the direct product of the cyclic subgroups generated by the equivalence classes of the A1