The Single State Dominance Hypothesis and the Two-Neutrino Double Beta Decay of Mo100

The hypothesis of the single state dominance (SSD) in the calculation of the two-neutrino double beta decay of Mo100 is tested by exact consideration of the energy denominators of the perturbation theory. Both transitions to the ground state as well as to the 0+ and 2+ excited states of the final nucleus Ru100 are considered. We demonstrate, that by experimental investigation of the single electron energy distribution and the angular correlation of the outgoing electrons, the SSD hypothesis can be confirmed or ruled out by a precise two-neutrino double beta decay measurement (e.g. by NEMO III collaboration).Comment: 13 pages, RevTex, 1 figur

Analysis of solar neutrino induced double beta processes for several nuclei

We investigate neutrino flux induced double beta transitions in targets built of Cd112, Cd114, Cd116 and O18 isotopes. In addition to known beta^- beta^- channel we consider new beta^- beta^+ and beta^- beta^+ gamma modes of the neutrino induced double beta process. A possibility of detection of the solar neutrinos via the induced double beta transitions of interest is discussed. We note that the beta^- part of the solar neutrino induced beta^- beta^+ process in O18 was already discussed in Ref. [9,10] in connection with a possible influence of high energy electron production of this origin on the SuperKamiokande results.Comment: 5 pages, LaTeX. Talk presented by S. V. Semenov on International Workhop on Non-Accelerator New Physics (NANP'01), Dubna, Russia, June 2001, to be published in Phys. Atom. Nucl. (2002

EVALUATION OF CONDITIONS CONCERNING THE DEVELOPMENT OF TOURISM. INVESTIGATION INTO THE BASIN OF THE PARSĘTA RIVER

DOI: 10.2478/v10089-008-0021-7 Available on-line at: http://www.bulletinofgeography.umk.pl http://versita.com/bgssThe article presents the results of multidimensional evaluation of conditions concerning the development of tourism in rural areas of Parsęta basin. For the purpose the synthetic measure has been applied in reference to 27 variables divided into two groups: suitable for tourism or investing. Having conducted the analysis of the selected variables, the investigated area was divided into three regions: the seaside at the North with very good conditions for the development of the touristic function as its core function, the central region, highly diversified with only moderate touristic capabilities, and finally the southern region, the lake district, with adequate features for the development of tourism

Nuclear muon-positron conversion mediated by Majorana neutrinos

We study lepton number violating (LNV) process of muon-positron conversion in nuclei mediated by the exchange of light and heavy Majorana neutrinos. Nuclear structure calculations have been carried out for the case of experimentally interesting nucleus 48Ti in the framework of renormalized proton-neutron Quasiparticle Random Phase Approximation. We demonstrate that the imaginary part of the amplitude of light Majorana neutrino exchange mechanism gives an appreciable contribution to the muon-positron conversion rate. This specific feature is absent in the allied case of neutrinoless double beta decay. Using the present neutrino oscillations, tritium beta decay, accelerator and cosmological data we derived the limits on the effective masses of light _{\mu e} and heavy _{\mu e} neutrinos. The expected rates of muon-positron nuclear conversion, corresponding to these limits, were found to be so small that even within a distant future the muon-positron conversion experiments will hardly be able to detect the neutrino signal. Therefore, searches for this LNV process can only rely on the presence of certain physics beyond the trivial extension of the Standard Model by inclusion of massive Majorana neutrinos.Comment: 28 pages, 3 figures. Added comments, references and one figure. Typos in eqs. (18), (19) correcte

Neutrino statistics and big bang nucleosynthesis

Neutrinos may possibly violate the spin-statistics theorem, and hence obey Bose statistics or mixed statistics despite having spin half. We find the generalized equilibrium distribution function of neutrinos which depends on a single fermi-bose parameter, \kappa, and interpolates continuously between the bosonic and fermionic distributions when \kappa changes from -1 to +1. We consider modification of the Big Bang Nucleosynthesis (BBN) in the presence of bosonic or partly bosonic neutrinos. For pure bosonic neutrinos the abundances change (in comparison with the usual Fermi-Dirac case) by -3.2% for 4He (which is equivalent to a decrease of the effective number of neutrinos by \Delta N_\nu = - 0.6), +2.6% for 2H and -7% for 7Li. These changes provide a better fit to the BBN data. Future BBN studies will be able to constrain the fermi-bose parameter to \kappa > 0.5, if no deviation from fermionic nature of neutrinos is found. We also evaluate the sensitivity of future CMB and LSS observations to the fermi-bose parameter.Comment: 11 pages, 3 figures, matches version in JCAP, discussion and references extended slightl

Predicted bacterial interactions affect in vivo microbial colonization dynamics in Nematostella

The maintenance and resilience of host-associated microbiota during development is a fundamental process influencing the fitness of many organisms. Several host properties were identified as influencing factors on bacterial colonization, including the innate immune system, mucus composition and diet. In contrast, the importance of bacteria-bacteria interactions on host colonization is less understood. Here, we use bacterial abundance data of the marine model organism Nematostella vectensis to reconstruct potential bacteria-bacteria interactions through co-occurrence networks. The analysis indicates that bacteria-bacteria interactions are dynamic during host colonization and change according to the host’s developmental stage. To assess the predictive power of inferred interactions, we tested bacterial isolates with predicted cooperative or competitive behavior for their ability to influence bacterial recolonization dynamics. Within three days of recolonization all tested bacterial isolates affected bacterial community structure, while only competitive bacteria increased bacterial diversity. Already one week after recolonization almost no differences in bacterial community structure could be observed between control and treatments. These results show that predicted competitive bacteria can influence community structure for a short period of time, verifying the in silico predictions. However, within one week, the effects of the bacterial isolates are neutralized, indicating a high degree of resilience of the bacterial community. Hanna Domin1, Yazmín H. Zurita-Gutiérrez2, Marco Scotti3, Jann Buttlar1, Ute Hentschel Humeida2 and Sebastian Fraune1

Topographical expression of class IA and class II phosphoinositide 3-kinase enzymes in normal human tissues is consistent with a role in differentiation

BACKGROUND: Growth factor, cytokine and chemokine-induced activation of PI3K enzymes constitutes the start of a complex signalling cascade, which ultimately mediates cellular activities such as proliferation, differentiation, chemotaxis, survival, trafficking, and glucose homeostasis. The PI3K enzyme family is divided into 3 classes; class I (subdivided into IA and IB), class II (PI3K-C2α, PI3K-C2β and PI3K-C2γ) and class III PI3K. Expression of these enzymes in human tissue has not been clearly defined. METHODS: In this study, we analysed the immunohistochemical topographical expression profile of class IA (anti-p85 adaptor) and class II PI3K (PI3K-C2α and PI3K-C2β) enzymes in 104 formalin-fixed, paraffin embedded normal adult human (age 33–71 years, median 44 years) tissue specimens including those from the gastrointestinal, genitourinary, hepatobiliary, endocrine, integument and lymphoid systems. Antibody specificity was verified by Western blotting of cell lysates and peptide blocking studies. Immunohistochemistry intensity was scored from undetectable to strong. RESULTS: PI3K enzymes were expressed in selected cell populations of epithelial or mesenchymal origin. Columnar epithelium and transitional epithelia were reactive but mucous secreting and stratified squamous epithelia were not. Mesenchymal elements (smooth muscle and endothelial cells) and glomerular epithelium were only expressed PI3K-C2α while ganglion cells expressed p85 and PI3K-C2β. All three enzymes were detected in macrophages, which served as an internal positive control. None of the three PI3K isozymes was detected in the stem cell/progenitor compartments or in B lymphocyte aggregates. CONCLUSIONS: Taken together, these data suggest that PI3K enzyme distribution is not ubiquitous but expressed selectively in fully differentiated, non-proliferating cells. Identification of the normal in vivo expression pattern of class IA and class II PI3K paves the way for further analyses which will clarify the role played by these enzymes in inflammatory, neoplastic and other human disease conditions

Limits on different Majoron decay modes of 100^{100}Mo and 82^{82}Se for neutrinoless double beta decays in the NEMO-3 experiment

The NEMO-3 tracking detector is located in the Fr\'ejus Underground Laboratory. It was designed to study double beta decay in a number of different isotopes. Presented here are the experimental half-life limits on the double beta decay process for the isotopes $^{100}$Mo and $^{82}$Se for different Majoron emission modes and limits on the effective neutrino-Majoron coupling constants. In particular, new limits on "ordinary" Majoron (spectral index 1) decay of $^{100}$Mo ($T_{1/2} > 2.7\cdot10^{22}$ y) and $^{82}$Se ($T_{1/2} > 1.5\cdot10^{22}$ y) have been obtained. Corresponding bounds on the Majoron-neutrino coupling constant are $< (0.4-1.9) \cdot 10^{-4}$ and $< (0.66-1.7) \cdot 10^{-4}$.Comment: 23 pages includind 4 figures, to be published in Nuclear Physics