Impact of the 6^6Li asymptotic normalization constant onto α\alpha-induced reactions of astrophysical interest

Indirect methods have become the predominant approach in experimental nuclear astrophysics for studying several low-energy nuclear reactions occurring in stars, as direct measurements of many of these relevant reactions are rendered infeasible due to their low reaction probability. Such indirect methods, however, require theoretical input that in turn can have significant poorly-quantified uncertainties, which can then be propagated to the reaction rates and have a large effect on our quantitative understanding of stellar evolution and nucleosynthesis processes. We present two such examples involving $\alpha$-induced reactions, $^{13}$C($\alpha,n)^{16}$O and $^{12}$C$(\alpha,\gamma)^{16}$O, for which the low-energy cross sections have been constrained with $(^6$Li$,d)$ transfer data. In this Letter, we discuss how a first-principle calculation of $^6$Li leads to a 21% reduction of the $^{12}$C$(\alpha,\gamma)^{16}$O cross sections with respect to a previous estimation. This calculation further resolves the discrepancy between recent measurements of the $^{13}$C$(\alpha,n)^{16}$O reaction and points to the need for improved theoretical formulations of nuclear reactions.Comment: 6 pages (including references) and 3 figure

Direct observation of the glue pairing the halo of the nucleus 11Li

With the help of a unified description of the nuclear structure and of the direct reaction mechanism we show that a recent 1H(11Li,9Li)3H experiment provides, for the first time in nuclear physics, direct evidence of phonon mediated pairing.Comment: 9 pages, 4 figures. Major change

Comorbidities and Treatment-Limiting Decisions in Older Adults Dying in the Emergency Department: Is There an Association?

International audienc

Antimicrobial resistance, virulence factorsand genetic lineages of hospital-onsetmethicillin-resistant Staphylococcus aureus isolates detected in a hospital in Zaragoza

Introduction MRSA population dynamics is undergoing significant changes, and for this reason it is important to know which clones are circulating in our nosocomial environment. Materials and methods A total of 118 MRSA isolates were collected from clinical samples from patients with previous hospital or healthcare contact (named as hospital-onset MRSA (HO-MRSA)) during a one year period. Susceptibility testing was performed by disk diffusion and microdilution. The presence of resistance genes and virulence factors were tested by PCR. All isolates were typed by SCCmec, spa and agr typing. PFGE and MLST were applied to a selection of them. Results Eighty-three HO-MRSA isolates (70.3%) were resistant to any antibiotic included in the macrolide–lincosamide–streptogramin B group. Among these isolates, the M phenotype was the most frequent (73.5%). One hundred and seven of HO-MRSA isolates (90.7%) showed aminoglycoside resistance. The combination aac(6')-Ie-aph(2")-Ia + ant(4')-Ia genes was the most frequent (22.4%). Tetracycline resistance rates in HO-MRSA isolates were low (3.4%), although a high level of mupirocin resistance was observed (25.4%). Most of the HO-MRSA isolates (approximately 90%) showed SCCmec type IVc and agr type II. Fifteen unrelated pulsotypes were identified. CC5 was the most prevalent (88.1%), followed by CC8 (5.9%), CC22 (2.5%), CC398 (2.5%) and CC1 (0.8%). Conclusion CC5/ST125/t067 lineage was the most frequent. This lineage was related to aminoglycoside resistance, and to a lesser extent, with macrolide resistance. The presence of international clones as EMRSA-15 (CC22/ST22), European clones as CC5/ST228, community clones related to CC1 or CC8 and livestock associated clones, as CC398, were observed in a low percentage

Phonon Mode Spectroscopy, Electron-Phonon Coupling and the Metal-Insulator Transition in Quasi-One-Dimensional M2Mo6Se6

We present electronic structure calculations, electrical resistivity data and the first specific heat measurements in the normal and superconducting states of quasi-one-dimensional M2Mo6Se6 (M = Tl, In, Rb). Rb2Mo6Se6 undergoes a metal-insulator transition at ~170K: electronic structure calculations indicate that this is likely to be driven by the formation of a dynamical charge density wave. However, Tl2Mo6Se6 and In2Mo6Se6 remain metallic down to low temperature, with superconducting transitions at Tc = 4.2K and 2.85K respectively. The absence of any metal-insulator transition in these materials is due to a larger in-plane bandwidth, leading to increased inter-chain hopping which suppresses the density wave instability. Electronic heat capacity data for the superconducting compounds reveal an exceptionally low density of states DEF = 0.055 states eV^-1 atom^-1, with BCS fits showing 2Delta/kBTc >= 5 for Tl2Mo6Se6 and 3.5 for In2Mo6Se6. Modelling the lattice specific heat with a set of Einstein modes, we obtain the approximate phonon density of states F(w). Deconvolving the resistivity for the two superconductors then yields their electron-phonon transport coupling function a^2F(w). In Tl2Mo6Se6 and In2Mo6Se6, F(w) is dominated by an optical "guest ion" mode at ~5meV and a set of acoustic modes from ~10-30meV. Rb2Mo6Se6 exhibits a similar spectrum; however, the optical phonon has a lower intensity and is shifted to ~8meV. Electrons in Tl2Mo6Se6 couple strongly to both sets of modes, whereas In2Mo6Se6 only displays significant coupling in the 10-18meV range. Although pairing is clearly not mediated by the guest ion phonon, we believe it has a beneficial effect on superconductivity in Tl2Mo6Se6, given its extraordinarily large coupling strength and higher Tc compared to In2Mo6Se6.Comment: 16 pages, 13 figure

Cooper pair sizes in 11Li and in superfluid nuclei: a puzzle?

We point out a strong influence of the pairing force on the size of the two neutron Cooper pair in $^{11}$Li, and to a lesser extent also in $^6$He. It seems that these are quite unique situations, since Cooper pair sizes of stable superfluid nuclei are very little influenced by the intensity of pairing, as recently reported. We explore the difference between $^{11}$Li and heavier superfulid nuclei, and discuss reasons for the exceptional situation in $^{11}$Li.Comment: 9 pages. To be published in J. of Phys. G special issue on Open Problems in Nuclear Structure (OPeNST

Novel Methodologies for Providing In Situ Data to HAB Early Warning Systems in the European Atlantic Area: The PRIMROSE Experience

Harmful algal blooms (HABs) cause harm to human health or hinder sustainable use of the marine environment in Blue Economy sectors. HABs are temporally and spatially variable and hence their mitigation is closely linked to effective early warning. The European Union (EU) Interreg Atlantic Area project “PRIMROSE”, Predicting Risk and Impact of Harmful Events on the Aquaculture Sector, was focused on the joint development of HAB early warning systems in different regions along the European Atlantic Area. Advancement of the existing HAB forecasting systems requires development of forecasting tools, improvements in data flow and processing, but also additional data inputs to assess the distribution of HAB species, especially in areas away from national monitoring stations, usually located near aquaculture sites. In this contribution, we review different novel technologies for acquiring HAB data and report on the experience gained in several novel local data collection exercises performed during the project. Demonstrations include the deployment of autonomous imaging flow cytometry (IFC) sensors near two aquaculture areas: a mooring in the Daoulas estuary in the Bay of Brest and pumping from a bay in the Shetland Islands to an inland IFC; and several drone deployments, both of Unmanned Aerial Vehicles (UAV) and of Autonomous Surface vehicles (ASVs). Additionally, we have reviewed sampling approaches potentially relevant for HAB early warning including protocols for opportunistic water sampling by coastguard agencies. Experiences in the determination of marine biotoxins in non-traditional vectors and how they could complement standard routine HAB monitoring are also considered.En prens

Statistical properties of the well deformed 153,155^{153,155}Sm nuclei and the scissors resonance

The Nuclear Level Densities (NLDs) and the $\gamma$-ray Strength Functions ($\gamma$SFs) of $^{153,155}$Sm have been extracted from (d,p$\gamma$) coincidences using the Oslo method. The experimental NLD of $^{153}$Sm is higher than the NLD of $^{155}$Sm, in accordance with microscopic calculations. The $\gamma$SFs of $^{153,155}$Sm are in fair agreement with QRPA calculations based on the D1M Gogny interaction. An enhancement is observed in the $\gamma$SF for both $^{153,155}$Sm nuclei around 3 MeV in excitation energy and is attributed to the M1 Scissors Resonance (SR). Their integrated strengths were found to be in the range 1.3 - 2.1 and 4.4 - 6.4 $\mu^{2}_{N}$ for $^{153}$Sm and $^{155}$Sm, respectively. The strength of the SR for $^{155}$Sm is comparable to those for deformed even-even Sm isotopes from nuclear resonance fluorescence measurements, while that of $^{153}$Sm is lower than expected