28 research outputs found
Investigation of the nucleon-nucleon tensor force in the three-nucleon system
Proton-deuteron elastic scattering has been investigated at Ep =22.7 MeV by comparison of rigorous Faddeev calculations with experimental results. The observable most sensitive to the tensor force is the nucleon-nucleon polarization transfer coefficient Kyy'. The new angular distribution of Kyy' clearly favours the tensor force of the Bonn A potential, which is weaker than the one of the Paris potential.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28425/1/0000208.pd
Environmental Efficiency, Emission Trends and Labour Productivity: Trade-Off or Joint Dynamics? Empirical Evidence Using NAMEA Panel Data
Nuclear spectroscopy of 26Al
The tensor analyzing powers T20 and the cross sections for the reaction to levels in 26Al with excitation energies up to 6 MeV have been measured at θlab = 175°. The bombarding energy was varied in steps of 0.5 MeV from 10.0 to 12.5 MeV. Comparison of the measured T20 values with theoretical predictions, taking into account the finite-angle effect, has led to assignments of natural or unnatural parity to some fifty levels in 26Al. Two levels with Jπ = 0− could be identified on the basis of such a comparison. A (probable) assignment of Jπ = 0+ could be made to two levels in 26Al on the basis of a very low observed cross section. The information on spin-parity combinations found in this work was combined with spectroscopic data from other reactions to deduce new unambiguous Jπ assignments for 33 levels and Jπ restrictions for another three level
Investigation of [epsilon]1 and the 3PJ phase shifts in the n-p system by the measurement of polarization transfer coefficients in p-d elastic scattering
The 3S1-3D1 mixing parameter [epsilon]1 and the 3PJ phase shifts in the N-N system at low energy are investigated in the three nucleon system. The sensitivity of polarization transfer coefficients in p-d elastic scattering is determined by rigorous Faddeev calculations using Paris and Bonn potentials. The experimental results of Kyy' favours the tensor force component of the Bonn A potential.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28721/3/0000542.pd
Data on the interaction of protons and ? particles at center-of-mass energies up to 50 MeV
Rationale and plan for vitamin D food fortification: a review and guidance paper
Vitamin D deficiency can lead to musculoskeletal diseases such as rickets and osteomalacia, but vitamin D supplementation may also prevent extraskeletal diseases such as respiratory tract infections, asthma exacerbations, pregnancy complications and premature deaths. Vitamin D has a unique metabolism as it is mainly obtained through synthesis in the skin under the influence of sunlight (i.e., ultraviolet-B radiation) whereas intake by nutrition traditionally plays a relatively minor role. Dietary guidelines for vitamin D are based on a consensus that serum 25-hydroxyvitamin D (25[OH]D) concentrations are used to assess vitamin D status, with the recommended target concentrations ranging from >= 25 to >= 50 nmol/L (>= 10->= 20 ng/mL), corresponding to a daily vitamin D intake of 10 to 20 mu g (400-800 international units). Most populations fail to meet these recommended dietary vitamin D requirements. In Europe, 25(OH)D concentrations < 30 nmol/L (12 ng/mL) and < 50 nmol/L (20 ng/mL) are present in 13.0 and 40.4% of the general population, respectively. This substantial gap between officially recommended dietary reference intakes for vitamin D and the high prevalence of vitamin D deficiency in the general population requires action from health authorities. Promotion of a healthier lifestyle with more outdoor activities and optimal nutrition are definitely warranted but will not erase vitamin D deficiency and must, in the case of sunlight exposure, be well balanced with regard to potential adverse effects such as skin cancer. Intake of vitamin D supplements is limited by relatively poor adherence (in particular in individuals with low-socioeconomic status) and potential for overdosing. Systematic vitamin D food fortification is, however, an effective approach to improve vitamin D status in the general population, and this has already been introduced by countries such as the US, Canada, India, and Finland. Recent advances in our knowledge on the safety of vitamin D treatment, the dose-response relationship of vitamin D intake and 25(OH)D levels, as well as data on the effectiveness of vitamin D fortification in countries such as Finland provide a solid basis to introduce and modify vitamin D food fortification in order to improve public health with this likewise cost-effective approach