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The g-factor of the ground state of 31Al (T1/2=640 ms) has been measured by the β-NMR technique on a polarized secondary fragment beam at GANIL, Caen, France. The measured value of |g|=1.517(20) is compared with sd-shell model calculations, which allows the assignment of spin and parity Iπ=5/2+ to this state. The spectroscopy of neutron-rich Al isotopes on the border of the “island of inversion” is discussed in terms of the persistence of the N=20 shell closure for Z=13 nuclei. [Copyright &y& Elsevier]

An experiment was performed at GANIL using a high-intensity 58Ni beam at 74.5 MeV/nucleon on a nickel target. The projectile fragments produced in the high-acceptance SISSI device were selected in the LISE3 spectrometer using the Wien filter. The detection setup performed an unambiguous identification of four 48Ni implantation events. A lower limit of its half-life of the order of 0.5 μs and an estimate of the production cross section of about 0.05 pb were deduced. In addition, a few tens of 45Fe and 49Ni nuclei were implanted, which may give information on their decay modes. Besides, 48Ni and 45Fe are very good candidates for two-proton radioactivity, still to be observed. [Copyright &y& Elsevier]

Decay spectroscopy was performed for neutron-deficient nuclei ranging from zinc to krypton with isospin -32≤Tz≤0. Measurements of correlated β-delayed protons allowed us to determine the isobaric analog states fed from the decay of 65Se and 69Kr, constraining the spin of the 69Kr ground state. Preliminary results regarding the half lives for the Tz=-1 systems, relevant to the rapid proton capture (rp) process, are discussed. [ABSTRACT FROM AUTHOR]

The MORA (M atter's O rigin from the R adioA ctivity of trapped and oriented ions) project aims at measuring with unprecedented precision the D correlation in the nuclear beta decay of trapped and oriented ions. The D correlation offers the possibility to search for new CP-violating interactions, complementary to searches done at the LHC and with electric dipole moments. Technically, MORA uses an innovative in-trap orientation method which combines the high trapping efficiency of a transparent Paul trap with laser orientation techniques. The trapping, detection, and laser setups are under development. The project will first focus on the proof-of-principle of the in-trap laser orientation technique, before the actual measurement of the D correlation in the decay of 23Mg+ ions is undertaken firstly at JYFL and then later, at GANIL, with full sensitivity to new physics. [ABSTRACT FROM AUTHOR]

The unbound 12O nucleus was studied via the two-neutron transfer (p,t) reaction in inverse kinematics using a radioactive 14O beam at 51 MeV/u. Excitation energy spectra and differential cross sections were deduced by the missing mass method using MUST2 telescopes. We achieved much higher statistics compared to the previous experiments of 12O, which allowed accurate determination of resonance energy and unambiguous spin and parity assignment. The 12O resonance previously reported using the same reaction was confirmed at an excitation energy of 1.62±0.03(stat.)±0.10(syst.). MeV and assigned spin and parity of 0+ from a distorted-wave Born approximation analysis of the differential cross sections. Mirror symmetry of 12O with respect to its neutron-rich partner 12Be is discussed from the energy difference of the second 0+ states. In addition, from systematics of known 0+ states, a distinct correlation is revealed between the mirror energy difference and the binding energy after carrying out a scaling with the mass and the charge. We show that the mirror energy difference of the observed 0+ state of 12O is highly deviated from the systematic trend of deeply bound nuclei and in line with the scaling relation found for weakly bound nuclei with a substantial 2s1/2 component. The importance of the scaling of mirror asymmetry is discussed in the context of ab initio calculations near the drip lines and universality of few-body quantum systems. [ABSTRACT FROM AUTHOR]

The efficiency of the weak s process in low-metallicity rotating massive stars depends strongly on the rates of the competing ^{17}O(α,n)^{20}Ne and ^{17}O(α,γ)^{21}Ne reactions that determine the potency of the ^{16}O neutron poison. Their reaction rates are poorly known in the astrophysical energy range of interest for core helium burning in massive stars because of the lack of spectroscopic information (partial widths, spin parities) for the relevant states in the compound nucleus ^{21}Ne. In this Letter, we report on the first experimental determination of the α-particle spectroscopic factors and partial widths of these states using the ^{17}O(^{7}Li,t)^{21}Ne α-transfer reaction. With these the ^{17}O(α,n)^{20}Ne and ^{17}O(α,γ)^{21}Ne reaction rates were evaluated with uncertainties reduced by a factor more than 3 with respect to previous evaluations and the present ^{17}O(α,n)^{20}Ne reaction rate is more than 20 times larger. The present (α,n)/(α,γ) rate ratio favors neutron recycling and suggests an enhancement of the weak s process in the Zr-Nd region by more than 1.5 dex in metal-poor rotating massive stars.

Hantavirus pulmonary syndrome (HPS) is a rodent-borne zoonotic disease that is endemic throughout the Americas. Agricultural activities increase exposure to wild rodents, especially for sugarcane cutters. We carried out a survey of the epidemiological aspects of HPS and investigated the prevalence of hantavirus infection in the sugarcane cutter population from different localities in the Brazilian Midwest region. We conducted a retrospective study of all confirmed HPS cases in the state of Goiás reported to the National HPS surveillance system between 2007 and 2017, along with a seroepidemiological study in a population of sugarcane cutters working in Goiás state in 2016, using the anti-hantavirus (Andes) ELISA IgG. A total of 634 serum samples from cane cutters were tested for hantavirus antibodies, with 44 (6.9%) being IgG-reactive according to ELISA. The destination of garbage was the only statistically significant variable ( p = 0.03) related to the detection of hantavirus IgG ( p < 0.05). We described the epidemiological profile of reported hantavirus cases in Goiás-a highly endemic area for HPS, and where the seroepidemiological study was conducted. Our results increase our knowledge about hantavirus infections in Brazil and highlight the vulnerability of sugarcane cutters to a highly lethal disease that, to date, has no specific treatment or vaccination.

Classical novae are thermonuclear explosions in stellar binary systems, and important sources of 26 Al and 22 Na. While γ rays from the decay of the former radioisotope have been observed throughout the Galaxy, 22 Na remains untraceable. Its half-life (2.6 yr) would allow the observation of its 1.275 MeV γ-ray line from a cosmic source. However, the prediction of such an observation requires good knowledge of its nucleosynthesis. The 22 Na(p, γ) 23 Mg reaction remains the only source of large uncertainty about the amount of 22 Na ejected. Its rate is dominated by a single resonance on the short-lived state at 7785.0(7) keV in 23 Mg. Here, we propose a combined analysis of particle-particle correlations and velocity-difference profiles to measure femtosecond nuclear lifetimes. The application of this method to the study of the 23 Mg states, places strong limits on the amount of 22 Na produced in novae and constrains its detectability with future space-borne observatories., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Subjecting a physical system to extreme conditions is one of the means often used to obtain a better understanding and deeper insight into its organization and structure. In the case of the atomic nucleus, one such approach is to investigate isotopes that have very different neutron-to-proton (N/Z) ratios than in stable nuclei. Light, neutron-rich isotopes exhibit the most asymmetric N/Z ratios and those lying beyond the limits of binding, which undergo spontaneous neutron emission and exist only as very short-lived resonances (about 10 -21  s), provide the most stringent tests of modern nuclear-structure theories. Here we report on the first observation of 28 O and 27 O through their decay into 24 O and four and three neutrons, respectively. The 28 O nucleus is of particular interest as, with the Z = 8 and N = 20 magic numbers 1,2 , it is expected in the standard shell-model picture of nuclear structure to be one of a relatively small number of so-called 'doubly magic' nuclei. Both 27 O and 28 O were found to exist as narrow, low-lying resonances and their decay energies are compared here to the results of sophisticated theoretical modelling, including a large-scale shell-model calculation and a newly developed statistical approach. In both cases, the underlying nuclear interactions were derived from effective field theories of quantum chromodynamics. Finally, it is shown that the cross-section for the production of 28 O from a 29 F beam is consistent with it not exhibiting a closed N = 20 shell structure., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

The predominant landscape of the Atlantic Forest of the Brazilian state of Rio de Janeiro is made up of forest fragments surrounded by a matrix of modified habitat, which may influence the occurrence and distribution of host species and their parasites in comparison with the original continuous forest. The present study describes the structure, composition, and diversity of the helminth community found in rodents in two areas of an open matrix of different status of conservation. The abundance, intensity, and prevalence were calculated for each helminth species in rodent species. The influence of biotic and abiotic factors on the abundance and prevalence of the helminth species was also investigated. Community structure was analyzed based on the beta diversity and a bipartite network. Nine helminth species were recovered from Akodon cursor , Necromys lasiurus and Mus musculus , with the greatest helminth species richness being recorded in A. cursor (S = 8), followed by N. lasiurus (S = 6), and M. musculus (S = 3). Only three of the helminths recorded in A. cursor had been recorded previously in this rodent in the Atlantic Forest, where 12 different helminths have been recorded, so that the other five are new occurrences for this rodent. All the helminth species of N. lasiurus had been reported previously in this rodent in the Cerrado and Caatinga regions. Mus musculus was infected with the same helminths as the local fauna. Host species and locality were the most important factors influencing helminth abundance and prevalence. Beta-diversity was high for infracommunities indicating more substitutions of helminth species than losses among individuals. Three helminths species were shared by the three host species. The reduced beta-diversity observed in the component communities was consistent with the overlap observed in the helminth fauna of the host species., (© 2021 The Authors.)

Detailed spectroscopy of the neutron-unbound nucleus ^{28}F has been performed for the first time following proton/neutron removal from ^{29}Ne/^{29}F beams at energies around 230  MeV/nucleon. The invariant-mass spectra were reconstructed for both the ^{27}F^{(*)}+n and ^{26}F^{(*)}+2n coincidences and revealed a series of well-defined resonances. A near-threshold state was observed in both reactions and is identified as the ^{28}F ground state, with S&#95;{n}(^{28}F)=-199(6)  keV, while analysis of the 2n decay channel allowed a considerably improved S&#95;{n}(^{27}F)=1620(60)  keV to be deduced. Comparison with shell-model predictions and eikonal-model reaction calculations have allowed spin-parity assignments to be proposed for some of the lower-lying levels of ^{28}F. Importantly, in the case of the ground state, the reconstructed ^{27}F+n momentum distribution following neutron removal from ^{29}F indicates that it arises mainly from the 1p&#95;{3/2} neutron intruder configuration. This demonstrates that the island of inversion around N=20 includes ^{28}F, and most probably ^{29}F, and suggests that ^{28}O is not doubly magic.

Necromys lasiurus is a generalist rodent that is thought to be the main reservoir of the Araraquara hantavirus, which causes Hantavirus Pulmonary Syndrome, in the Brazilian Cerrado savanna. This species occurs naturally in the open habitats of the Cerrado, Pantanal and Caatinga biomes, where it often occurs at high densities, although the distribution of the species has recently been observed expanding into the Brazilian state of Rio de Janeiro. This study aimed to map the occurrence of N. lasiurus within the Atlantic Forest of Rio de Janeiro state and discuss the potential role of the species as a reservoir of the Araraquara hantavirus in these areas. The study was based on a comprehensive literature search and four expeditions for the collection of specimens in the state of Rio de Janeiro. The data were used to predict the distribution of N. lasiurus, confirm the distribution of the species in the state, and detect the rates of hantavirus infection in these rodents. Necromys lasiurus has been recorded at 16 localities in 10 municipalities of Rio de Janeiro state. The relative abundance of N. lasiurus was low at all localities, except for the REBIO Poço das Antas and APA-BRSJ, two protected areas. Necromys lasiurus was associated primarily with landscapes dominated by farmland (plantations or pasture) at relatively low altitudes in the vicinity of bodies of water. A total of 204 serum samples were collected, but none were reactive for hantavirus. The distribution of N. lasiurus is expanding into many areas of the anthropogenic matrix, but it is not usually either abundant or dominant in these areas. The relatively reduced abundance of N. lasiurus in Rio de Janeiro and the lack of infection in all the areas investigated indicate that it is unlikely to be a reservoir of hantavirus in this region in the near future., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Purpose: To evaluate whether losartan is able to induce beige adipocytes formation, focusing on the thermogenic gene expression and adipocyte remodeling in the subcutaneous white adipose tissue of diet-induced obese mice., Methods: Male C57BL/6 mice received a control diet (10% energy as lipids) or a high-fat diet (50% energy as lipids) for 10 weeks, followed by a 5-week treatment with losartan: control group, control-losartan group (10 mg/Kg/day), high-fat group and high-fat-losartan group (10 mg/Kg/day). Biochemical, morphometrical, stereological and molecular approaches were used to evaluate the outcomes., Results: The high-fat diet elicited overweight, insulin resistance and adipocyte hypertrophy in the high-fat group, all of which losartan rescued in the high-fat-losartan group. These effects comply with the induction of beige adipocytes within the inguinal fat pads in high-fat-losartan group as they exhibited the greatest energy expenditure among the groups along with the presence uncoupling protein 1 positive multilocular adipocytes with enhanced peroxisome proliferator-activated receptor gamma coactivator 1-alpha and PR domain containing 16 mRNA levels, indicating a significant potential for mitochondrial biogenesis and adaptive thermogenesis., Conclusions: Our results show compelling evidence that losartan countered diet-induced obesity in mice by enhancing energy expenditure through beige adipocytes induction. Reduced body mass, increased insulin sensitivity, decreased adipocyte size and marked expression of uncoupling protein 1 by ectopic multilocular adipocytes support these findings. The use of losartan as a coadjutant medicine to tackle obesity and its related disorders merits further investigation.

The decay of (19)O(β(-)) and (19)Ne(β(+)) implanted in niobium in its superconducting and metallic phases was measured using purified radioactive beams produced by the SPIRAL GANIL facility. Half-lives and branching ratios measured in the two phases are consistent within a 1σ error bar. This measurement casts strong doubts on the predicted strong electron screening in a superconductor, the so-called superscreening. The measured difference in screening potential energy is 110(90) eV for (19)Ne and 400(320) eV for (19)O. Precise determinations of the half-lives were obtained for (19)O, 26.476(9) s, and for (19)Ne, 17.254(5) s.

Six proton-emitting states in 19Ne were studied through the inelastic scattering reaction H(19Ne,p);{19}Ne; (p)18F. Their energies and widths were derived from the protons detected at zero degree, while proton-proton angular correlations between the detector at zero degree and a segmented annular detector were used to determine their spin value. In addition to the known states, a new broad J=1/2 resonance has been evidenced at E&#95;{x} approximately 7.9 MeV, approximately 1.45 MeV above the proton emission threshold. By introducing this resonance, the 18F(p,alpha)15O destruction rate in novae is significantly enhanced. This reduces the chance to observe the cosmic gamma-ray emission of 18F from novae in space telescopes.

The decay of the ground-state two-proton emitter 45Fe was studied with a time-projection chamber and the emission of two protons was unambiguously identified. The total decay energy and the half-life measured in this work agree with the results from previous experiments. The present result constitutes the first direct observation of the individual protons in the two-proton decay of a long-lived ground-state emitter. In parallel, we identified for the first time directly two-proton emission from 43Cr, a known beta-delayed two-proton emitter. The technique developed in the present work opens the way to a detailed study of the mechanism of ground state as well as beta-delayed two-proton radioactivity.

A new isomeric 0(+) state was identified as the first excited state in the self-conjugate (N=Z) nucleus 72Kr. By combining for the first time conversion-electron and gamma-ray spectroscopy with the production of metastable states in high-energy fragmentation, the electric-monopole decay of the new isomer to the ground state was established. The new 0(+) state is understood as the band head of the known prolate rotational structure, which strongly supports the interpretation that 72Kr is one of the rare nuclei having an oblate-deformed ground state. This observation gives in fact the first evidence for a shape isomer in a N=Z nucleus.

The neutron-rich (66,68)Ni have been produced at GANIL via interactions of a 65.9A MeV 70Zn beam with a 58Ni target. Their reduced transition probability B(E2;0(+)(1)-->2+) has been measured for the first time by Coulomb excitation in a (208)Pb target at intermediate energy. The B(E2) value for (68)Ni(40) is unexpectedly small. An analysis in terms of large scale shell model calculations stresses the importance of proton core excitations to reproduce the B(E2) values and indicates the erosion of the N = 40 harmonic-oscillator subshell by neutron-pair scattering.

The ground state of the proton-rich, unbound nucleus 11N was observed, together with six excited states using the multinucleon transfer reaction 10B(14N,13B)11N at 30A MeV incident energy at Grand Accelerateur National d'Ions Lourds. Levels of 11N are observed as well defined resonances in the spectrum of the 13B ejectiles. They are localized at 1.63(5), 2.16(5), 3.06(8), 3.61(5), 4.33(5), 5.98(10), and 6.54(10) MeV above the 10C+p threshold. The ground-state resonance has a mass excess of 24.618(50) MeV; the experimental width is smaller than theoretical predictions.