The thermonuclear production of F19 by Wolf-Rayet stars revisited

New models of rotating and non-rotating stars are computed for initial masses between 25 and 120 Msun and for metallicities Z = 0.004, 0.008, 0.020 and 0.040 with the aim of reexamining the wind contribution of Wolf-Rayet (WR) stars to the F19 enrichment of the interstellar medium. Models with an initial rotation velocity vini = 300 km/s are found to globally eject less F19 than the non-rotating models. We compare our new predictions with those of Meynet & Arnould (2000), and demonstrate that the F19 yields are very sensitive to the still uncertain F19(alpha,p)Ne22 rate and to the adopted mass loss rates. Using the recommended mass loss rate values that take into account the clumping of the WR wind and the NACRE reaction rates when available, we obtain WR F19 yields that are significantly lower than predicted by Meynet & Arnould (2000), and that would make WR stars non-important contributors to the galactic F19 budget. In view, however, of the large nuclear and mass loss rate uncertainties, we consider that the question of the WR contribution to the galactic F19 remains quite largely open.Comment: 9 pages, 5 figures, accepted for publication in Astronomy & Astrophysic

Decreased Fat Storage by Lactobacillus Paracasei Is Associated with Increased Levels of Angiopoietin-Like 4 Protein (ANGPTL4)

Background: Intervention strategies for obesity are global issues that require immediate attention. One approach is to exploit the growing consensus that beneficial gut microbiota could be of use in intervention regimes. Our objective was to determine the mechanism by which the probiotic bacteria Lactobacillus paracasei ssp paracasei F19 (F19) could alter fat storage. Angiopoietin-like 4 (ANGPTL4) is a circulating lipoprotein lipase (LPL) inhibitor that controls triglyceride deposition into adipocytes and has been reported to be regulated by gut microbes. Methodology/Principal Findings: A diet intervention study of mice fed high-fat chow supplemented with F19 was carried out to study potential mechanistic effects on fat storage. Mice given F19 displayed significantly less body fat, as assessed by magnetic resonance imaging, and a changed lipoprotein profile. Given that previous studies on fat storage have identified ANGPTL4 as an effector, we also investigated circulating levels of ANGPTL4, which proved to be higher in the F19-treated group. This increase, together with total body fat and triglyceride levels told a story of inhibited LPL action through ANGPTL4 leading to decreased fat storage. Co-culture experiments of colonic cell lines and F19 were set up in order to monitor any ensuing alterations in ANGPTL4 expression by qPCR. We observed that potentially secreted factors from F19 can induce ANGPTL4 gene expression, acting in part through the peroxisome proliferator activated receptors alpha and gamma. To prove validity of in vitro findings, germ-free mice were monocolonized with F19. Here we again found change

Assessment of benefits and risks of probiotics in processed cereal-based baby foods Lactobacillus paracasei ssp. paracasei F19

Source at https://vkm.no/The Norwegian Scientific Committee for Food Safety (VKM) has appointed an ad hoc-group of experts to answer a request from the Norwegian Food Safety Authority regarding benefit and risk assessment of Lactobacillus paracasei ssp. paracasei F19 (F19) in processed cereal-based baby foods intended for small children 1-3 years. This assessment is based on the literature provided by the notifier as well as that found by a MEDLINE search.Vitenskapskomiteen for mattrygghet (VKM) har på oppdrag fra Mattilsynet utarbeidet en nytte- og risikovurdering av Lactobacillus paracasei ssp. paracasei F19 (F19) tilsatt i barnegrøt til barn i alderen 1-3 år. For å besvare oppdraget nedsatte VKM en ad hoc-gruppe. Vurderingen er basert på gjennomgang av litteratur tilsendt fra virksomheten og MEDLINE litteratursøk

Fluorine-plus-proton reactions

The properties of certain energy levels in O16, F19, and Ne20 have been studied by observations on the alpha particles and inelastic protons from the bombardment of fluorine by protons. A high-resolution magnetic analysis of the alpha-particle groups to the 2+ and 1- levels in O16 from the F19(p, α)O16* reaction failed to reveal any doublet structure in these known levels. The angular distributions of the alpha-particle groups to these levels did not indicate degeneracy with a 2- level, nor did a search for new excited levels in O16 up to 8.7-Mev excitation reveal a 2- level. These results are not in agreement with the alpha-particle model of the O16 nucleus which predicts a 2- state close in energy to the 2+ state. Angular distributions of the alpha particles were measured at proton bombarding energies of 873, 935, 1290, 1355, and 1381 kev. The distributions at 1355 kev indicated that the corresponding Ne20 resonance level at 14.16 Mev has spin 2 and odd parity. The spin and parity assignments previously found for the other levels were confirmed. A study of the inelastic proton groups from the F19(p, p′)F19* reaction gave 108.8±0.8 and 196.0±1.4 kev for the excitation energies of the two lowest excited levels of F19. The cross sections at the 1431-kev resonance for these groups in the center-of-mass system were 0.187±0.015 barn for the first group and 0.007 ±0.002 barn for the second group. At 1381 kev the cross section was 0.0427±0.0040 barn for protons to the second excited level. Angular distributions of the proton groups were measured and, in conjunction with other studies made in this laboratory, resulted in spin and parity assignments of ½- and 3/2+ for the first and second excited states of F19, respectively

The Berlin Exoplanet Search Telescope II. Catalog of Variable Stars. I. Characterization of Three Southern Target Fields

A photometric survey of three Southern target fields with BEST II yielded the detection of 2,406 previously unknown variable stars and an additional 617 stars with suspected variability. This study presents a catalog including their coordinates, magnitudes, light curves, ephemerides, amplitudes, and type of variability. In addition, the variability of 17 known objects is confirmed, thus validating the results. The catalog contains a number of known and new variables that are of interest for further astrophysical investigations, in order to, e.g., search for additional bodies in eclipsing binary systems, or to test stellar interior models. Altogether, 209,070 stars were monitored with BEST II during a total of 128 nights in 2009/2010. The overall variability fraction of 1.2-1.5% in these target fields is well comparable to similar ground-based photometric surveys. Within the main magnitude range of $R\in\left[11,17\right]$, we identify 0.67(3)% of all stars to be eclipsing binaries, which indicates a completeness of about one third for this particular type in comparison to space surveys.Comment: accepted to A

Assessment of benefits and risks of probiotics in processed cereal-based baby foods Lactobacillus paracasei ssp. paracasei F19

The Norwegian Scientific Committee for Food Safety (VKM) has on request from the Norwegian Food Safety Authority performed a benefit and risk assessment of Lactobacillus paracasei ssp. paracasei F19 (F19) in processed cerealbased baby foods intended for small children 1-3 years. This assessment is based on the literature provided by the notifier as well as that found by a MEDLINE search. A notification regarding two products of processed cereal-based baby foods (hereafter called cereals), intended for small children and supplemented with the bacterium F19 initiated this work