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In the nuclear tunneling processes involving deformed nuclei, most of the tunneling-related quantities depend on the relative orientations of the participating nuclei. In the presence of different multipole deformations, we study the variation of a few relevant quantities for the α-decay and the sub-barrier fusion processes, in an orientation degree of freedom. The knocking frequency and the penetration probability are evaluated within the Wentzel–Kramers–Brillouin approximation. The interaction potential is calculated with Skyrme-type nucleon–nucleon interaction. We found that the width of the potential pocket, the Coulomb barrier radius, the penetration probability, the α-decay width, and the fusion cross-section follow consistently the orientation-angle variation of the radius of the deformed nucleus. The orientation distribution patterns of the pocket width, the barrier radius, the logarithms of the penetrability, the decay width, and the fusion cross-section are found to be highly analogous to pattern of the deformed-nucleus radius. The curve patterns of the orientation angle distributions of the internal pocket depth, the Coulomb barrier height and width, as well as the knocking frequency simulate inversely the variation of the deformed nucleus radius. The predicted orientation behaviors will be of a special interest in predicting the optimum orientations for the tunneling processes. [ABSTRACT FROM AUTHOR]

Purpose: A prospective cohort study was conducted to analyze whether self-reported fatigue predicts overall survival in patients with esophageal cancer. Methods: Patients enrolled in the Mayo Clinic Esophageal Adenocarcinoma and Barrett's Esophagus Registry between September 2001 and January 2009 who completed a baseline quality of life instrument were eligible for evaluation. The fatigue component was scored on a 0-10 scale, with 0 as extreme fatigue. Patients were categorized as having a decreased energy level if they reported a score of ≤5. Fatigue scores ≥6 reflect normal levels of energy. Results: Data from a total of 659 enrolled patients were analyzed. A total of 392 (59 %) and 267 (41 %) patients reported decreased and normal energy, respectively. Univariate analysis indicates patients with normal energy had improved 5-year survival compared to patients with decreased energy (37 vs 28 %, hazard ratio (HR) 0.74, p = 0.006). Among the patients with locally advanced disease, the same relationship was seen (28 vs 17 %, HR = 0.67, p = 0.003); this remained significant on multivariate analysis (HR = 0.71, p = 0.015). Conclusions: A decreased energy level is associated with poor survival in patients with esophageal cancer. Thus, patients with high levels of fatigue should be referred for psychological support and be considered for therapy aimed at amelioration of fatigue symptoms. [ABSTRACT FROM AUTHOR]

The structure of some even-even superheavy nuclei with the proton number Z = 98−120 is studied using a semi-microscopic but not self-consistent model. The macroscopic energy part is obtained from the Skyrme nucleon-nucleon interaction in the semi-classical extended Thomas-Fermi approach. A simple but accurate method is derived for calculating the direct part of the Coulomb energy. The microscopic shell plus pairing energy corrections are calculated from the traditional Strutinsky method. Within this semi-microscopic approach, the total energy curves with the quadrupole deformation of the studied superheavy nuclei were calculated. The same approach features the well known Pb or U nuclei. For each nucleus the model predictions for the binding energy, the deformation parameters, the half-density radii and comparison with other theoretical models are made. The calculated binding energies are in good agreement with the available experimental data. [ABSTRACT FROM AUTHOR]

The oceans have absorbed nearly half of the fossil-fuel carbon dioxide (CO2) emitted into the atmosphere since pre-industrial times, causing a measurable reduction in seawater pH and carbonate saturation. If CO2 emissions continue to rise at current rates, upper-ocean pH will decrease to levels lower than have existed for tens of millions of years and, critically, at a rate of change 100 times greater than at any time over this period. Recent studies have shown effects of ocean acidification on a variety of marine life forms, in particular calcifying organisms. Consequences at the community to ecosystem level, in contrast, are largely unknown. Here we show that dissolved inorganic carbon consumption of a natural plankton community maintained in mesocosm enclosures at initial CO2 partial pressures of 350, 700 and 1,050 μatm increases with rising CO2. The community consumed up to 39% more dissolved inorganic carbon at increased CO2 partial pressures compared to present levels, whereas nutrient uptake remained the same. The stoichiometry of carbon to nitrogen drawdown increased from 6.0 at low CO2 to 8.0 at high CO2, thus exceeding the Redfield carbon:nitrogen ratio of 6.6 in today’s ocean. This excess carbon consumption was associated with higher loss of organic carbon from the upper layer of the stratified mesocosms. If applicable to the natural environment, the observed responses have implications for a variety of marine biological and biogeochemical processes, and underscore the importance of biologically driven feedbacks in the ocean to global change. [ABSTRACT FROM AUTHOR]