Rotational bands in Quadrupole-Octupole Collective Model

A collective bands of positive and negative parity could be composed of the vibrations and rotations. The rotations of the octupole configurations can be based either on the axial or the non-axial octupole vibrations. A consistent approach to the quadrupole-octupole collective vibrations coupled with the rotational motion enables to distinguish between various scenarios of disappearance of the E2 transitions in negative-parity bands. The here presented theoretical estimates are compared with the recent experimental energies and transition probabilities in and between the ground-state and low-energy negaive-parity bands in $^{156}$Dy. A realistic collective Hamiltonian contains the potential energy term obtained through the macroscopic-microscopic Strutinsky-like method with particle-number-projected BCS approach and deformation-dependent mass tensor defined in vibrational-rotational, nine-dimensional collective space. The symmetrization procedure ensures the uniqueness of the Hamiltonian eigensolutions with respect to the laboratory coordinate system. This quadrupole-octupole collective approach may also allow to find and/or verify some fingerprints of possible high-order symmetries (e.g. tetrahedral, octahedral,...) in nuclear collective bands.Comment: 10 pages, 5 figure

Interaction Strengths for the Fock-Space Formulation of the Nuclear Pairing Problem

A realistic nuclear mean-field hamiltonian with pairing has been diagonalized using Fock space representation that allows for nearly exact treatment of the problem. Calculations were performed for all the even-even nuclei with Z in (20, 100), whose pairing gaps were possible to extract out of the experimental masses. The optimal values of the pairing strength constants for the protons and neutrons have been found.Comment: Seminar given at XXXVII School of Physics in Zakopane, Poland. Paper in LaTeX, 4 pages including one figure, submitted to Acta Physica Polonica

Sequential fissions of heavy nuclear systems

In Xe+Sn central collisions from 12 to 20 MeV/A measured with the INDRA 4$\pi$ multidetector, the three-fragment exit channel occurs with a significant cross section. In this contribution, we show that these fragments arise from two successive binary splittings of a heavy composite system. Strong Coulomb proximity effects are observed in the three-fragment final state. By comparison with Coulomb trajectory calculations, we show that the time scale between the consecutive break-ups decreases with increasing bombarding energy, becoming compatible with quasi-simultaneous multifragmentation above 18 MeV/A.Comment: 6 pages, 5 figures, contribution to conference proceedings of the Fifth International Workshop on Nuclear fission and Fission-Product Spectroscop

HIGH-SENSITIVITY C-REACTIVE PROTEIN (hsCRP) IN YOUNG ADULTS: RELATION TO AEROBIC CAPACITY, PHYSICAL ACTIVITY AND RISK FACTORS FOR CARDIOVASCULAR DISEASES

Atheromatosis develops as a result of a chronic inflammatory process of the arteries. Inflammatory biomarkers, particularly high-sensitivity C-reactive protein (hsCRP), positively correlate with atheromatosis risk factors and can be used to estimate and predict the risk of cardiovascular events. The purpose of this study was to evaluate the relationship between hsCRP concentration and BMI, body composition, classical risk factors for cardiovascular diseases, energy expenditure for physical activity (WEE) and  ·VO2max. 166 volunteers (78 women and 88 men) were included in the examinations. Their mean age was 20.2±0.9 years. Health condition was described by the following variables: smoking, WEE,  ·VO2max, body mass index (BMI), waist-to-hip ratio (WHR), fat mass (FM), fat-free mass (FFM), lipid profile, hsCRP, glucose and insulin concentration, and insulin resistance. Between the subgroups created on the basis of hsCRP concentration, in quartiles 1 to 3 and quartile 4, a comparative analysis was carried out. 79.5�0of women and 69.3�0of men had hsCRP values within the references ranges. Moderately high values were found in 14.1�0of women and 22.7�0of men and high in 6.4�0and 7.9�20respectively. Mean values of BMI, FFM, WHR, WEE,  ·VO2max, glucose and triglyceride concentration, and TC/HDL index were significantly lower, while FM and HDL were significantly higher, in women than in men. In the quartile 4 subgroup compared to the quartile 1-3 subgroup, we found significantly lower HDL concentration and a tendency for higher values of BMI (p=0.06) and TC (p=0.07) as well as higher percentages of smoking among men. In young, physically active, healthy persons, serum concentration of hsCRP is not related to physical activity or  ·VO2max

Reversible suppression of an essential gene in adult mice using transgenic RNA interference

RNAi has revolutionized loss-of-function genetics by enabling sequence-specific suppression of virtually any gene. Furthermore, tetracycline response elements (TRE) can drive expression of short hairpin RNAs (shRNAs) for inducible and reversible target gene suppression. Here, we demonstrate the feasibility of transgenic inducible RNAi for suppression of essential genes. We set out to directly target cell proliferation by screening an RNAi library against DNA replication factors and identified multiple shRNAs against Replication Protein A, subunit 3 (RPA3). We generated transgenic mice with TRE-driven Rpa3 shRNAs whose expression enforced a reversible cell cycle arrest. In adult mice, the block in cell proliferation caused rapid atrophy of the intestinal epithelium which led to weight loss and lethality within 8-11 d of shRNA induction. Upon shRNA withdrawal, villus atrophy and weight loss were fully reversible. Thus, shRpa3 transgenic mice provide an interesting tool to study tissue maintenance and regeneration. Overall, we have established a robust system that serves the purpose of temperature-sensitive alleles in other model organisms, enabling inducible and reversible suppression of essential genes in a mammalian system