Spinless bosons embedded in a vector Duffin-Kemmer-Petiau oscillator

Some properties of minimal and nonminimal vector interactions in the Duffin-Kemmer-Petiau (DKP) formalism are discussed. The conservation of the total angular momentum for spherically symmetric nonminimal potentials is derived from its commutation properties with each term of the DKP equation and the proper boundary conditions on the spinors are imposed. It is shown that the space component of the nonminimal vector potential plays a crucial role for the confinement of bosons. The exact solutions for the vector DKP oscillator (nonminimal vector coupling with a linear potential which exhibits an equally spaced energy spectrum in the weak-coupling limit) for spin-0 bosons are presented in a closed form and it is shown that the spectrum exhibits an accidental degeneracy

Inconsistencies of a purported probability current in the Duffin-Kemmer-Petiau theory

The Duffin-Kemmer-Petiau (DKP) equation with a square step potential is used in a simple way with polymorphic purposes. It proves adequate to refuse a proposed new current that is currently interpreted as a probability current,to show that the Klein paradox does exist in the DKP theory and to revise other minor misconceptions diffused in the literature.Comment: 11 page

Effects due to a scalar coupling on the particle-antiparticle production in the Duffin-Kemmer-Petiau theory

The Duffin-Kemmer-Petiau formalism with vector and scalar potentials is used to point out a few misconceptions diffused in the literature. It is explicitly shown that the scalar coupling makes the DKP formalism not equivalent to the Klein-Gordon formalism or to the Proca formalism, and that the spin-1 sector of the DKP theory looks formally like the spin-0 sector. With proper boundary conditions, scattering of massive bosons in an arbitrary mixed vector-scalar square step potential is explored in a simple way and effects due to the scalar coupling on the particle-antiparticle production and localization of bosons are analyzed in some detail

The Duffin-Kemmer-Petiau oscillator

In view of current interest in relativistic spin-one systems and the recent work on the Dirac Oscillator, we introduce the Duffin-Kemmer-Petiau (DKP) equation obtained by using an external potential linear in r. Since, in the non-relativistic limit, the spin 1 representation leads to a harmonic oscillator with a spin-orbit coupling of the Thomas form, we call the equation the DKP oscillator. This oscillator is a relativistic generalization of the quantum harmonic oscillator for scalar and vector bosons. We show that it conserves total angular momentum and that it is exactly solvable. We calculate and discuss the eigenspectrum of the DKP oscillator in the spin 1 representation

Determining the activity of 241Pu by liquid scintillation counting

Liquid scintillation counting (LSC) is one of the most widely used methods for determining the activity of 241Pu. One of the main challenges of this counting method is the efficiency calibration of the system for the low beta energies of 241Pu (E max=20.8 keV). In this paper we compare the two most frequently used methods, the CIEMAT/NIST efficiency tracing (CNET) method and the experimental quench correction curve method. Both methods proved to be reliable, and agree within their uncertainties, for the expected quenching conditions of the source

An effective singular oscillator for Duffin-Kemmer-Petiau particles with a nonminimal vector coupling: a two-fold degeneracy

Scalar and vector bosons in the background of one-dimensional nonminimal vector linear plus inversely linear potentials are explored in a unified way in the context of the Duffin-Kemmer-Petiau theory. The problem is mapped into a Sturm-Liouville problem with an effective singular oscillator. With boundary conditions emerging from the problem, exact bound-state solutions in the spin-0 sector are found in closed form and it is shown that the spectrum exhibits degeneracy. It is shown that, depending on the potential parameters, there may or may not exist bound-state solutions in the spin-1 sector.Comment: 1 figure. arXiv admin note: substantial text overlap with arXiv:1009.159

Activity standardisation of 177Lu.

<sup>177</sup> Lu decays through low-energy β <sup>-</sup> - and γ-emissions in addition to conversion and Auger electrons. To support the use of this radiopharmaceutical in Switzerland, a <sup>177</sup> Lu solution was standardised using the β-γ coincidence technique, as well as the TDCR method. The solution had no <sup>177m</sup> Lu impurity. Primary coincidence measurements, with plastic scintillators for beta detection, were carried out using both analogue and digital electronics. TDCR measurements using only defocusing were also made. Monte Carlo calculations were used to compute the detection efficiency. The coincidence measurements with both analogue and digital electronics are compatible within one standard uncertainty, but they are lower than (and discrepant with) the TDCR measurements. An ampoule of this solution was submitted to the BIPM as a contribution to the Système International de Référence

Characterization of intestinal microbiota in celiac children

Celiac disease (CD) is enteropathy autoimmune induced by the ingestion of gluten in genetically predisposed subjects. The ingestion of gluten is responsible for the symptoms of CD, and a disturber of the intestinal microbiota. In this study, 13 Samples of intestinal biopsy, 15 fecal samples from celiac children, and 10 from controls children respectively were collected and analyzed by conventional culture technique to characterize the microbial profile intestinal of celiac children. There was 24 celiac children (8 boys), Mean age at diagnosis was 9.52 years, all have clinical manifestations, positive anti-transglutaminase antibodies and mucosal lesions suggestive of CD (Marsh Classification).We found a difference in intestinal microbiota, between celiac and controls children for example  the  Enterobacteria,  Clostridium sp and Staphylococcus sp were remarkably higher in biopsy and fecal samples of celiac children than in controls. Inversely the Enterococcus sp, Lactobacillus sp and Clostridium sp were slightly lower in celiac children. Our results indicate an imbalance in intestinal microbiota for celiac children as reduction in the numbers of Lactobacillus sp, Enterococcus sp and increases in the numbers of Enterobacteria, Staphylococcus sp and Clostridium sp.Keywords: Celiac disease, Intestinal Microbiota, Anti-transglutaminase, Lacobacillus sp