Search

The isovector and isoscalar components of neutron-proton pairing are investigated in the N=Z unstable nuclei of the fp-shell through the two-nucleon transfer reaction (p,$^{3}$He) in inverse kinematics. The combination of particle and gamma-ray detection with radioactive beams of $^{56}$Ni and $^{52}$Fe, produced by fragmentation at the GANIL/LISE facility, made it possible to carry out this study for the first time in a closed and an open-shell nucleus in the fp-shell. The transfer cross-sections for ground-state to ground-state (J=0$^{+}$, T=1) and to the first (J=1$^{+}$, T=0) state were extracted for both cases together with the transfer cross-section ratios σ(0+,T=1)/σ(1+,T=0). They are compared with second-order distorted-wave born approximation (DWBA) calculations. The enhancement of the ground-state to ground-state pair transfer cross-section close to mid-shell, in $^{52}$Fe, points towards a superfluid phase in the isovector channel. For the “deuteron-like” transfer, very low cross-sections to the first (J=1$^{+}$, T=0) state were observed both for $^{56}$Ni(p,$^{3}$He) and $^{52}$Fe(p,$^{3}$He) and are related to a strong hindrance of this channel due to spin-orbit effect. No evidence for an isoscalar deuteron-like condensate is observed.

International audience; The low-lying structure of $^{15}$C has been investigated via the neutron-removal $^{16}$C$(d,t)$ reaction. Along with bound neutron sd-shell hole states, unbound p-shell hole states have been firmly confirmed. The excitation energies and the deduced spectroscopic factors of the cross-shell states are an important measure of the $[(p)^{-1}(sd)^{2}]$ neutron configurations in $^{15}$C. Our results show a very good agreement with shell-model calculations using the SFO-tls interaction for $^{15}$C. However, a modification of the $p$-$sd$ and $sd$-$sd$ monopole terms was applied in order to reproduce the $N=9$ isotone $^{17}$O. In addition, the excitation energies and spectroscopic factors have been compared to the first calculations of $^{15}$C with the $ab~ initio$ self-consistent Green's function method employing the NNLO$_{sat}$ interaction. The results show the sensitivity to the size of the $N=8$ shell gap and highlight the need of going beyond the current truncation scheme in the theory.

Oral rotavirus vaccine efficacy estimates from randomised controlled trials are highly variable across settings. Although the randomised study design increases the likelihood of internal validity of findings, results from trials may not always apply outside the context of the study due to differences between trial participants and the target population. Here, we used a weight-based method to transport results from a monovalent rotavirus vaccine clinical trial conducted in Malawi between 2005 and 2008 to a target population of all trial-eligible children in Malawi, represented by data from the 2015-2016 Malawi Demographic and Health Survey (DHS). We reweighted trial participants to reflect the population characteristics described by the Malawi DHS. Vaccine efficacy was estimated for 1008 trial participants after applying these weights such that they represented trial-eligible children in Malawi. We also conducted subgroup analyses to examine the heterogeneous treatment effects by stunting and tuberculosis vaccination status at enrolment. In the original trial, the estimates of one-year vaccine efficacy against severe rotavirus gastroenteritis and any-severity rotavirus gastroenteritis in Malawi were 49.2% (95% CI 15.6%-70.3%) and 32.1% (95% CI 2.5%-53.1%), respectively. After weighting trial participants to represent all trial-eligible children in Malawi, vaccine efficacy increased to 62.2% (95% CI 35.5%-79.0%) against severe rotavirus gastroenteritis and 38.9% (95% CI 11.4%-58.5%) against any-severity rotavirus gastroenteritis. Rotavirus vaccine efficacy may differ between trial participants and target populations when these two populations differ. Differences in tuberculosis vaccination status between the trial sample and DHS population contributed to varying trial and target population vaccine efficacy estimates.

The authors apologize for an error in the published version of the above article. In the visualization of deep brain stimulation contact point positions (Figure 1 and Supplementary Figure E), left and right were swapped. As a result, we wrongly stated that left-sided stimulation positions were correlated with the occurrence of post-operative apathy. Instead, this statement should have been made regarding right-sided stimulation positions. Since we did not elaborate on the lateralization of our results, the error did not affect the main conclusions of the article. Furthermore, the p-value displayed in Figure 1B did not match the p-value in the main text and the figure legend, which we have now corrected. We have now included the corrected versions of Figure 1 and Supplementary Figure E, as well as the corrections we have made to the main text:[Formula presented] Corrigendum Fig. 1 Stimulation locations of contact points in relation to change in apathy severityA) Stimulation locations in MNI-space (viewed from respectively dorsolateral left, posterior and dorsolateral right). The subthalamic nucleus (blue) and red nucleus (red) were added for reference purposes. Increases in apathy severity are color-coded, ranging from no increase (green/yellow) to strong increase (dark red). MNI, Montreal Neurological Institute; L, left; R, right.B) Stimulation locations were projected on a vector through the longitudinal axis of the STN, where negative values indicated more ventromedial stimulation positions. There was a significant correlation between stimulation position and increase in apathy severity for the right side (r(24) = 0.498, p = 0.010), but not for the left side (r(24) = 0.141, p = 0.491). [Formula presented] Corrigendum Supplementary Fig. E Stimulation locations of contact points in relation to improvement in motor score. Stimulation locations in MNI-space (viewed from respectively dorsolateral left, posterior and dorsolateral right). The subthalamic nucleus (blue) and red nucleus (red) were added for reference purposes. Improvements in motor score (% UPDRS-III, contrasting pre- versus post-DBS scores) are color-coded, ranging from no improvement (green/yellow) to strong improvement (dark red). Next, stimulation locations were projected on a vector through the longitudinal axis of the STN, where negative values indicated more ventromedial stimulation positions. There were no significant correlations between stimulation position and improvement in motor performance; left side (r(24) = 0.055, p = 0.788); right side (r(24) = −0.197, p = 0.335). MNI, Montreal Neurological Institute; L, left; R, right; UPDRS-III, Unified Parkinson's disease Rating Scale, motor part. Correction to abstract. The paragraph describing the results was changed into: “Results: …For the right hemisphere, increase in apathy was associated with a more dorsolateral stimulation location (p = 0.010) …” Correction to results. Apathy and DBS localization. This paragraph was changed into: “. There was a significant correlation between a more dorsolateral stimulation position (along a vector) and increase in apathy severity post-DBS for the right side (p = 0.010), but not for the left side (p = 0.491; Fig.1B). In contrast, there was no relationship between stimulation position (along the same vector) and the degree of improvement in total motor score (UPDRS-III; Supplementary Fig E). Next, we performed a hierarchical linear regression model using A backward elimination method to study the relationship between stimulation location and change in apathy score, including the following covariates: pre-to post-operative change in executive functioning, depression score, anxiety score, LEDD total, LEDD of dopamine agonist, and motor function. For the right side this resulted in the following model: R2 = 0.465; change in depression score, b(standardized) = 0.587, p = 0.039; stimulation position, b(standardized) = 0.727, p = 0.015. For the left side no statistically significant model could be fitted. Correction to discussion. The first paragraph of the discussion section was changed into: “.The pre-to-post-DBS increase in apathy severity was associated with a more dorsolateral position of the stimulation for the right hemisphere, …” The fourth paragraph of the discussion section was changed into: “. In addition, we observed a significant correlation between increase in pre-to-post DBS apathy score and a more dorsolateral stimulation location relative to the STN for the right hemisphere, but not for the left hemisphere. As the occurrence of apathy has previously not been related to laterality of DBS [45,46], we refrain from drawing any conclusions from this left-right difference.” The sixth paragraph of the discussion section was changed into: “… In our study increases in apathy severity were not associated with changes in executive functioning, whereas in the multiple regression model there was a relation between improvement in depression scores and better apathy scores after surgery (in the context of right-sided stimulation). It remains to be determined whether the occurrence of apathy after DBS has a cognitive or emotional-affective basis.” The final paragraph of the discussion section was changed into: “In conclusion, we found that increase in apathy severity after STN-DBS might well be an effect of the stimulation itself. Increased apathy severity scores correlated with a more dorsolateral stimulation location (right hemisphere) and with …”

Proton-emission branches of the 10+ isomer in the Tz=−1 nucleus $^{54}$Ni have been imaged with the active target and time projection chamber (ACTAR TPC) in an experiment conducted at the Grand Accélérateur National d'Ions Lourds (GANIL). The completed decay scheme allows derivation of the reduced transition strengths, B(E2;10+→8+) and B(E4;10+→6+), for the two competing γ-ray transitions. By means of a comparison with their well-known ‘mirror transitions’ in Tz=+1 $^{54}$Fe, and aided by a variety of shell-model calculations in the fp model space, effective charges for E4 transitions near N=Z $^{56}$Ni can be deduced: επ≈1.40 and εν≈0.30. Mirror-energy differences are explored with various shell-model interactions and isospin-symmetry breaking terms.

International audience; The structure of the unbound F15 nucleus is investigated using the inverse kinematics resonant scattering of a radioactive O14 beam impinging on a CH2 target. The analysis of H1(O14,p)O14 and H1(O14,2p)N13 reactions allowed the confirmation of the previously observed narrow 1/2− resonance, near the two-proton decay threshold, and the identification of two new narrow 5/2− and 3/2− resonances. The newly observed levels decay by 1p emission to the ground of O14, and by sequential 2p emission to the ground state of N13 via the 1− resonance of O14. Gamow shell model (GSM) analysis of the experimental data suggests that the wave functions of the 5/2− and 3/2− resonances may be collectivized by the continuum coupling to nearby 2p- and 1p-decay channels. The observed excitation function H1(O14,p)O14 and resonance spectrum in F15 are well reproduced in the unified framework of the GSM.

The structure of the unbound $^{15}$F nucleus is investigated using the inverse kinematics resonant scattering of a radioactive $^{14}$O beam impinging on a CH$_2$ target. The analysis of $^{1}$H($^{14}$O,p)$^{14}$O and $^{1}$H($^{14}$O,2p)$^{13}$N reactions allowed the confirmation of the previously observed narrow $1/2^{-}$ resonance, near the two-proton decay threshold, and the identification of two new narrow 5/2$^{-}$ and 3/2$^{-}$ resonances. The newly observed levels decay by 1p emission to the ground of $^{14}$O, and by sequential 2p emission to the ground state (g.s.) of $^{13}$N via the $1^-$ resonance of $^{14}$O. Gamow shell model (GSM) analysis of the experimental data suggests that the wave functions of the 5/2$^{-}$ and 3/2$^{-}$ resonances may be collectivized by the continuum coupling to nearby 2p- and 1p- decay channels. The observed excitation function $^{1}$H($^{14}$O,p)$^{14}$O and resonance spectrum in $^{15}$F are well reproduced in the unified framework of the GSM., Comment: 7 pages, 4 figures