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International audience; The unstable N=42 nucleus 72Zn has been studied using multiple safe Coulomb excitation in inverse kinematics. The experiment was performed at the REX-ISOLDE facility at CERN making first use of the silicon detector array C-REX in combination with the γ-ray spectrometer Miniball. The high angular coverage of C-REX allowed to determine the reduced transition strengths for the decay of the yrast 01+, 21+ and 41+ as well as of the 02+ and 22+ states in 72Zn. The quadrupole moments of the 21+, 41+ and 22+ states were extracted. Using model independent quadrupole invariants, the ground state of 72Zn was found to have an average deformation in the γ degree of freedom close to maximum triaxiality. In comparison to experimental data in zinc isotopes with N<40, the collectivity of the 41+ state in neutron-rich 72Zn is significantly larger, indicating a collective yrast band based on the ground state of 72Zn. In contrast, a low experimental B(E2;02+→21+) strength was determined, indicating a different structure for the 02+ state. Shell-model calculations propose a 02+ state featuring a larger fraction of the (spherical) N=40 closed-shell configuration in its wave function than for the 01+ ground state. The results were also compared with beyond mean field calculations which corroborate the large deformation in the γ degree of freedom, while pointing to a more deformed 02+ state. These experimental and theoretical findings establish the importance of the γ degree of freedom in the ground state of 72Zn, located between the 68,70Ni nuclei that have spherical ground states, and 76Ge, which has a rigid triaxial shape.

The aim of this study was to identify developmental patterns of job insecurity, taking into account quantitative as well as qualitative job insecurity, and to examine if these groups vary with regard to different work-related learning aspects, that is, occupational self-efficacy, learning from supervisor and colleagues, and acquired knowledge and skills (KSAOs). We conducted latent class growth analysis using three-wave data of 1366 Dutch employees. Five job insecurity patterns were identified: (1) high stable (n = 132), (2) moderate-low stable (n = 555), (3) low stable (n = 217), (4) decreasing (n = 357) and (5) increasing (n = 105). In every class, the change pattern was similar for quantitative and qualitative job insecurity. Those in trajectories with high initial levels of job insecurity had lower initial levels of occupational self-efficacy, learning from others, and KSAOs than those with low initial levels of job insecurity. Additionally, job insecurity trajectories differed in the development of occupational self-efficacy over time. The findings indicate that there are distinct trajectories of the combination of quantitative and qualitative job insecurity, and that these demonstrate a substantial amount of heterogeneity concerning work-related learning.

Samenvatting In deze bijdrage wordt geexploreerd in hoeverre de coronacrisis van invloed is op onzekerheid over het voortbestaan van de arbeidsplaats, hier geoperationaliseerd als beroepsonzekerheid. Tevens wordt de samenhang onderzocht tussen beroepsonzekerheid en twee maatschappelijke attitudes: politieke machteloosheid en geloof in een coronasamenzwering. Vanuit de literatuur over samenzweringen wordt tot slot afgeleid dat beroepsonzekerheid met het geloof in een coronasamenzwering samenhangt, omdat dergelijk samenzweringsdenken een poging is om betekenis te geven aan een crisissituatie, zoals de coronapandemie. Deze hypothese wordt getoetst door na te gaan in hoeverre politieke machteloosheid de samenhang tussen beroepsonzekerheid en het geloof in een coronasamenzwering medieert. In december 2020 werden via een online survey data verzameld bij 1324 respondenten in Vlaanderen (Belgie). Alle hypothesen werden daarbij bevestigd. De resultaten suggereren dat de coronacrisis niet enkel van invloed was op onze gezondheid en ons gezondheidszorgsysteem, maar dat ook werkgerelateerde, politieke en maatschappelijke attitudes erdoor ‘geinfecteerd’ kunnen zijn.

5 pags., 3 figs., 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0, Gamow-Teller β decay is forbidden if the number of nodes in the radial wave functions of the initial and final states is different. This Δn=0 requirement plays a major role in the β decay of heavy neutron-rich nuclei, affecting the nucleosynthesis through the increased half-lives of nuclei on the astrophysical r-process pathway below both Z=50 (for N>82) and Z=82 (for N>126). The level of forbiddenness of the Δn=1ν1g →π0g transition has been investigated from the β decay of the ground state of Hg into the single-proton-hole nucleus Tl in an experiment at the ISOLDE Decay Station. From statistical observational limits on possible γ-ray transitions depopulating the π0g state in Tl, an upper limit of 3.9×10 % was obtained for the probability of this decay, corresponding to log⁡ft>8.8 within a 95% confidence limit. This is the most stringent test of the Δn=0 selection rule to date., Support from the European Union seventh framework through ENSAR contract no. 262010, the Science and Technology Facilities Council through grants ST/P005314/1, ST/L005743/1 and ST/J000051/1 (UK), the MINECO projects FPA2015-64969-P, FPA2015-65035-P and FPA2017-87568-P (Spain), FWO-Vlaanderen (Belgium), GOA/2015/010 (BOF KU Leuven), the Excellence of Science programme (EOS-FWO), and the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12) is acknowledged. ZsP acknowledges support by the ExtreMe Matter Institute EMMI at the GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany. PHR and SMJ ac-knowledge support from the UK Department for Business, Energy and Industrial Strategy via the National Measurement Office.

The structure of Po-208 populated through the EC/beta(+) decay of At-208 is investigated using gamma-ray spectroscopy at the ISOLDE Decay Station. The presented level scheme contains 27 new excited states and 43 new transitions, as well as a further 50 previously observed. rays which have been (re)assigned a position. The level scheme is compared to shell model calculations. Through this analysis approximately half of the beta-decay strength of At-208 is found to proceed via allowed decay and half via first-forbidden decay. The first-forbidden transitions predominantly populate core excited states at high excitation energies, which is qualitatively understood using shell model considerations. This mass region provides an excellent testing ground for the competition between allowed and first-forbidden beta-decay calculations, important for the detailed understanding of the nucleosynthesis of heavy elements.

The main aim of this study was to determine the agreement in classification between the modified KörperKoordinations Test für Kinder (KTK3+) and the Athletic Skills Track (AST) for measuring fundamental movement skill levels (FMS) in 6- to 12-year old children. 3,107 Dutch children (of which 1,625 are girls) between 6 and 12 years of age (9.1 ± 1.8 years) were tested with the KTK3+ and the AST. The KTK3+ consists of three items from the KTK and the Faber hand-eye coordination test. Raw scores from each subtest were transformed into percentile scores based on all the data of each grade. The AST is an obstacle course consisting of 5 (grades 3 till 5, 6–9 years) or 7 (grades 6 till 8, 9–12 years) concatenated FMS that should be performed as quickly as possible. The outcome measure is the time needed to complete the track. A significant bivariate Pearson correlation coefficient of 0.51 was found between the percentile sum score of the KTK3+ and the time to complete the AST, indicating that both tests measure a similar construct to some extent. Based on their scores, children were classified into one of five categories: 95%. Cross tabs revealed an agreement of 58.8% with a Kappa value of 0.15 between both tests. Less than 1% of the children were classified more than two categories higher or lower. The moderate correlation between the KTK3+ and the AST and the low classification agreement into five categories of FMS stress the importance to further investigate the test choice and the measurement properties (i.e., validity and reliability) of both tools. PE teachers needs to be aware of the context in which the test will be conducted, know which construct of motor competence they want to measure and know what the purpose of testing is (e.g., screening or monitoring). Based on these considerations, the most appropriate assessment tool can be chosen.

Physical review / C 102(5), 054304 (2020). doi:10.1103/PhysRevC.102.054304, Published by Inst., Woodbury, NY

The β decay of ^{208}Hg into the one-proton hole, one neutron-particle _{81}^{208}Tl_{127} nucleus was investigated at CERN-ISOLDE. Shell-model calculations describe well the level scheme deduced, validating the proton-neutron interactions used, with implications for the whole of the N>126, Z

The β decay of 207Hg into the single-proton-hole nucleus 207Tl has been studied through γ-ray spectroscopy at the ISOLDE Decay Station (IDS) with the aim of identifying states resulting from coupling of the πs−11/2, πd−13/2, and πh−111/2 shell model orbitals to the collective octupole vibration. Twenty-two states were observed lying between 2.6 and 4.0 MeV, eleven of which were observed for the first time, and 78 new transitions were placed. Two octupole states (s1/2-coupled) are identified and three more states (d3/2-coupled) are tentatively assigned using spin-parity inferences, while further h11/2-coupled states may also have been observed for the first time. Comparisons are made with state-of-the-art large-scale shell model calculations and previous observations made in this region, and systematic underestimation of the energy of the octupole vibrational states is noted. We suggest that in order to resolve the difference in predicted energies for collective and noncollective t=1 states (t is the number of nucleons breaking the 208Pb core), the effect of t=2 mixing may be reduced for octupole-coupled states. The inclusion of mixing with t=0,2,3 excitations is necessary to replicate all t=1 state energies accurately.

6 pags., 4 fig.s, 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0, There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate CP violation and hence probe physics beyond the Standard Model of particle physics. Isotopes of both radon and radium have been identified as candidates for such measurements. Here, we observed the low-lying quantum states in Rn and Rn by accelerating beams of these radioactive nuclei. We show that radon isotopes undergo octupole vibrations but do not possess static pear-shapes in their ground states. We conclude that radon atoms provide less favourable conditions for the enhancement of a measurable atomic electric-dipole moment., The support of the ISOLDE Collaboration and technical teams is acknowledged. This work was supported by the following Research Councils and Grants: Science and Technology Facilities Council (STFC; UK) grants ST/ P004598/1, ST/L005808/1; Federal Ministry of Education and Research (BMBF; Germany) grants 05P18RDCIA, 05P15PKCIA and 05P18PKCIA and the “Verbundprojekt 05P2018”; National Science Centre (Poland) grant 2015/18/M/ST2/00523; European Union’s Horizon 2020 Framework research and innovation programme 654002 (ENSAR2); Marie Skłodowska-Curie COFUND grant (EU-CERN) 665779; Research Foundation Flanders (FWO, Belgium), by GOA/2015/010 (BOF KU Leuven) and the Interuniversity Attraction Poles Programme initiated by the Belgian Science Policy Office (BriX network P7/12); RFBR(Russia) grant 17-52-12015.

There is sparse direct experimental evidence that atomic nuclei can exhibit stable "pear" shapes arising from strong octupole correlations. In order to investigate the nature of octupole collectivity in radium isotopes, electric octupole (E3) matrix elements have been determined for transitions in ^{222,228}Ra nuclei using the method of sub-barrier, multistep Coulomb excitation. Beams of the radioactive radium isotopes were provided by the HIE-ISOLDE facility at CERN. The observed pattern of E3 matrix elements for different nuclear transitions is explained by describing ^{222}Ra as pear shaped with stable octupole deformation, while ^{228}Ra behaves like an octupole vibrator.

5 pags., 4 figs., 1 tab. -- Addendum to: Nature Communications https://doi.org/10.1038/s41467-019-10494-5, published online 6 June 2019.

Data analysis of the Coulomb excitation experiment of the exotic 206Hg nucleus, recently performed at CERN’s HIE-ISOLDE facility, needs to account for the contribution to target excitation due to the strongly-present beam contaminant 130Xe. In this paper, the contamination subtraction procedure is presented.

6 pags., 6 figs. -- 27th International Nuclear Physics Conference (INPC2019) 29 July - 2 August 2019, Glasgow, UK, The neutron-deficient 115Cs was produced at ISOLDE, CERN by spallation reaction using 1.4 GeV proton on LaC2 target. The exotic decay modes were studied by using a charged particle array (DSSD and pad detectors) and a ¿-detector array (four Clovers) at the ISOLDE decay station (IDS). In this report, results on observed ß-delayed particle emission from 115Cs, a nucleus close to proton drip line, is presented. By measuring the time distribution in the delayed proton spectrum, the half-life of the ground state of 115Cs was extracted. The obtained half-life is in agreement with previous reported value. For the first time, the p-unbound states of 115Xe, obtained by measuring beta-delayed protons from 115Cs is reported., Ushasi Datta acknowledges with thanks to SERB, India for the financial support (travel) for attending and presenting the paper in the conference (INPC2019). Authors of SINP deeply acknowledge the SEND (XI th plan, DAE, India) and IENP/HENPP (XII th plan, DAE, India) project grant. This project has received funding from the European Union’s Horizon 2020 ENSAR2 project under grant agreement no 654002 and the Spanish research council under contract FPA2015-64969-P. The authors (P.Das and A.Bhattacharyya) acknowledge with thanks the financial support provided by the CSIR vide file number 09/489(0111)/2019EMR-I and 09/489(0115)/2019EMR-I respectively.

Background: South Africa is challenged with high levels of unemployment, comprising many people with low levels of education and also individuals who have never held a job before. Despite having many vulnerable participants, interventions aimed at the unemployed generally exclude psychosocial training and are methodologically weak. Aim: The JOBS programme, a scientifically sound intervention, has been developed specifically to help people affected by unemployment to cope with the psychological effects. As a means of applying such a programme in South Africa, this study aimed to develop a framework based on the insights gained on the implementation and evaluation of the JOBS programme. Methods: The study comprised a systematic review of literature regarding the JOBS intervention and its derivatives (n = 34). Results: The results revealed that populations similar to the unemployed in South Africa had benefitted significantly regarding re-employment and mental health outcomes. Conclusion: Suggestions derived from the literature included aiming the programme at the most vulnerable unemployed in South Africa: the youth and long-term unemployed. Furthermore, expanding the programme by adding an entrepreneurial component may yield positive results, considering the lack of employment opportunities in South Africa. © 2020. The Authors.

8 pags., 9 figs., We measured absolute cross sections for neutron transfer channels populated in the Rb-94 + Pb-208 binary reaction. Cross sections have been extracted identifying directly the lead isotopes with the high efficiency MINIBALL gamma-ray array coupled to a particle detector combined with a radioactive Rb-94 beam delivered at E-lab = 6.2 MeV/nucleon by the HIE-ISOLDE facility. We observed sizable cross sections in the neutron-rich mass region, where the heavy partner acquires neutrons. A fair agreement between the measured cross sections with those from GRAZING calculations gives confidence in the cross-section predictions of more neutron-rich nuclei produced via a larger number of transferred nucleons., This work was partly supported by the HORIZON 2020 ENSAR2 Grant Agreement no. 654002, and Marie Skłodowska-Curie COFUND (EU-CERN) grant agreement no. 665779, and by STFC (U.K.). This work has been supported in part by the Croatian Science Foundation under Project no. 7194 and in part under Project no. IP-2018-01- 1257, and the German BMBF under contract 05P18PKCIA + Verbundprojekt 05P2018

Purpose: To provide insight on the effect of wheelchair settings on wheelchair mobility performance (WMP). Methods: Twenty elite wheelchair basketball athletes of low (n = 10) and high classification (n = 10) were tested in a wheelchair-basketball-directed field test. Athletes performed the test in their own wheelchairs, which were modified for 5 additional conditions regarding seat height (high–low), mass (central–distributed), and grip. The previously developed inertial-sensor-based WMP monitor was used to extract wheelchair kinematics in all conditions. Results: Adding mass showed most effect on WMP, with a reduced average acceleration across all activities. Once distributed, additional mass also reduced maximal rotational speed and rotational acceleration. Elevating seat height had an effect on several performance aspects in sprinting and turning, whereas lowering seat height influenced performance minimally. Increased rim grip did not alter performance. No differences in response were evident between low- and high-classified athletes. Conclusions: The WMP monitor showed sensitivity to detect performance differences due to the small changes in wheelchair configuration. Distributed additional mass had the most effect on WMP, whereas additional grip had the least effect of conditions tested. Performance effects appear similar for both low- and high-classified athletes. Athletes, coaches, and wheelchair experts are provided with insight into the performance effect of key wheelchair settings, and they are offered a proven sensitive method to apply in sport practice, in their search for the best wheelchair–athlete combination. https://doi.org/10.1123/ijspp.2017-0641 LinkedIn: https://www.linkedin.com/in/rienkvdslikke/ https://www.linkedin.com/in/annemarie-de-witte-9582b154/ https://www.linkedin.com/in/moniqueberger/

In this study we measured the performance times on the Wheelchair Mobility Performance (WMP) test during different test conditions to see if the performance times changed when wheelchair settings were changed. The overall performance time on the WMP test increased when the tire pressure was reduced and also when extra mass was attached to the wheelchair. It can be concluded that the WMP test is sensitive to changes in wheelchair settings. It is recommended to use this field-based test in further research to investigate the effect of wheelchair settings on mobility performance time. Objective: The Wheelchair Mobility Performance (WMP) test is a reliable and valid measure to assess mobility performance in wheelchair basketball. The aim of this study was to examine the sensitivity to change of the WMP test by manipulating wheelchair configurations. Methods: Sixteen wheelchair basketball players performed the WMP test 3 times in their own wheelchair: (i) without adjustments (“control condition”); (ii) with 10 kg additional mass (“weighted condition”); and (iii) with 50% reduced tyre pressure (“tyre condition”). The outcome measure was time (s). If paired t-tests were significant (p

SpecMAT is a magnetic active target (AT) for transfer reaction studies with low-intensity radioactive ion beams at the ISOLDE facility (CERN). SpecMAT combines two types of detectors: a gas-filled time projection chamber (TPC), the core detector for tracking charged particles emitted in nuclear reactions, and an array of auxiliary scintillation detectors for in-flight γ -ray spectroscopy . All active target components are optimised for operation in a strong background magnetic field. The TPC has a cylindrical shape. Its electron detector is a bulk Micromegas segmented into 2916 triangular pads for sampling charged particle tracks . The scintillation array is composed of 45 detectors with cubic 48 × 48 × 48 mm 3 CeBr3 crystals. The General Electronics for TPC (GET) is used in SpecMAT to read out both detector types allowing correlation of the detected γ -rays with the TPC events. This article describes the SpecMAT active target and its characterisation with the α -decay of 241Am. A γ -ray spectrum obtained in correlation with 3D tracks left by charged particles in an active target is reported for the first time for such detectors.

© 2017 Human Kinetics, Inc. The aim of this study was to determine to what extent mobility performance is influenced by offensive or defensive situations and ball possession and to what extent these actions are different for the field positions. From video analysis, the relative duration of the various wheelchair movements during team offense/defense and individual ball possession was compared in 56 elite wheelchair basketball players. A two-way analysis of variance indicated that during offense, the guards and forwards performed longer driving forward than during defense. Overall, centers stood still longer during offense than during defense. Without ball, centers performed driving forward longer than with ball possession. It is concluded that offense, defense, and ball possession influenced mobility performance for the different field positions. These differences can be used to design specific training protocols. Furthermore, field positions require potentially different specific wheelchair configurations to improve performance.

Background: The neutron-deficient lead region provides a range of nuclear phenomena, including isomerism at low energies. This phenomenon can be studied by α decay because the degree of hindrance of α decay provides information on the change in nuclear structure of connected states. Purpose: The aim of this work was to investigate the α-decay properties of $^{200,202}$FR and daughter products. Method: Neutron-deficient francium nuclei are produced at ISOLDE-CERN bombarding a UCx target with 1.4 GeV protons. Surface ionization and mass-separation techniques were employed to provide a pure radioactive ion beam at a radiation-detection setup. Results: Due to the very high statistics and the high beam purity, improved decay data for $^{202}$FR and its daughters were obtained. In particular, this data set allowed us to identify many fine-structure α lines with a relative reduced α-decay width up to five orders of magnitude lower as the strongest ground-to-ground state or isomeric-to-isomeric state α-decay transition. In addition, several half-life values were extracted with similar or better precision as compared with the literature. Conclusions: The observation of crossover transitions positioned the isomeric high-spin level of $^{198}$At at an excitation energy of 265(3) keV. Half-life values of 4.47(5) s and 1.28(10) s were extracted for the ground state and isomeric state of $^{198}$At and 52(3) ms for the ground-state decay of $^{200}$FR. Furthermore, α-decay schemes for Fr202 and its daughter $^{198}$At could be constructed.

The structure of $^{34}$Si was studied through $\gamma$ spectroscopy separately in the $\beta^-$ decays of $^{34}$Mg and $^{34}$Al at the ISOLDE facility of CERN. Different configurations in $^{34}$Si were populated independently from the two recently identified $\beta$-decaying states in $^{34}$Al having spin-parity assignments $J^\pi = 4^-$ dominated by the normal configuration $\pi (d_{5/2})^{-1} \otimes \nu (f_{7/2})$ and $J^\pi = 1^+$ by the intruder configuration $\pi (d_{5/2})^{-1} \otimes \nu (d_{3/2})^{-1}(f_{7/2})^{2}$. The paper reports on spectroscopic properties of $^{34}$Si such as an extended level scheme, spin and parity assignments based on log($ft$) values and $\gamma$-ray branching ratios, absolute $\beta$ feeding intensities and neutron emission probabilities. A total of 11 newly identified levels and 26 transitions were added to the previously known level scheme of $^{34}$Si. Large scale shell-model calculations using the {\sc sdpf-u-mix} interaction, able to treat higher order intruder configurations, are compared with the new results and conclusions are drawn concerning the predictive power of {\sc sdpf-u-mix}, the $N=20$ shell gap, the level of mixing between normal and intruder configurations for the 0$_1^+$, 0$_2^+$ and 2$_1^+$ states and the absence of triaxial deformation in $^{34}$Si.

The structure of low-spin states originating from shape-coexisting configurations in $^{68}_{40}$Ni$_{28}$ was directly probed via the two-neutron transfer reaction $^{66}$Ni$(t,p)^{68}$Ni in inverse kinematics using a radioactive ion beam on a radioactive target. The direct feeding to the first excited 0$^+$ state was measured for center-of-mass angles 4°–16° and amounts to an integral of 4.2(16)% relative to the ground state. The observed difference in feeding of the 0$^+$ states is explained by the transfer of neutrons, mainly in the $pf$ shell below $N=40$ for the ground state, and across $N=40$ in the $g_{9/2}$ orbital for the 0$_2^+$, based on second-order distorted-wave Born approximation calculations combined with state-of-the-art shell-model two-nucleon amplitudes. However, the direct feeding to the 2$_1^+$ state [29(3)%] is incompatible with these calculations.

Hyperfine-structure parameters and isotope shifts for the 795-nm atomic transitions in $^{217,218,219}$At have been measured at CERN-ISOLDE, using the in-source resonance-ionization spectroscopy technique. Magnetic dipole and electric quadrupole moments, and changes in the nuclear mean-square charge radii, have been deduced. A large inverse odd-even staggering in radii, which may be associated with the presence of octupole collectivity, has been observed. Namely, the radius of the odd-odd isotope $^{218}$At has been found to be larger than the average of its even-$N$ neighbors, $^{217,219}$At. The discrepancy between the additivity-rule prediction and experimental data for the magnetic moment of $^{218}$At also supports the possible presence of octupole collectivity in the considered nuclei.

Excited states in Sn-133 were investigated through the beta decay of In-133 at the ISOLDE facility. The ISOLDE Resonance Ionization Laser Ion Source (RILIS) provided isomer-selective ionization for In-133, allowing us to study separately, and in detail, the beta-decay branch of In-133 J(pi)= (9/2(+)) ground state and its J(pi) = (1/2(-)) isomer.Thanks to the large spin difference of the two beta-decaying states of In-133, it is possible to investigate separately the lower and higher spin states in the daughter, Sn-133, and thus to probe independently different single-particle and single-hole levels. We report here new gamma transitions observed in the decay of In-133, including those assigned to the deexcitation of the neutron-unbound states.

Objective: This study aimed to investigate which characteristics of athlete, wheelchair and athlete-wheelchair interface are the best predictors of wheelchair basketball mobility performance. Design: A total of 60 experienced wheelchair basketball players performed a wheelchair mobility performance test to assess their mobility performance. To determine which variables were the best predictors of mobility performance, forward stepwise linear regression analyses were performed on a set of 33 characteristics, including 10 athlete, 19 wheelchair, and 4 athlete-wheelchair interface characteristics. Results: A total of 8 of the characteristics turned out to be significant predictors of wheelchair basketball mobility performance. Classification, experience, maximal isometric force, wheel axis height, and hand rim diameter—which both are interchangeable with each other and wheel diameter—camber angle, and the vertical distance between shoulder and rear wheel axis—which was interchangeable with seat height—were positively associated with mobility performance. The vertical distance between the front seat and the footrest was negatively associated with mobility performance. Conclusion: With this insight, coaches and biomechanical specialists are provided with statistical findings to determine which characteristics they could focus on best to improve mobility performance. Six out of 8 predictors are modifiable and can be optimized to improve mobility performance. These adjustments could be carried out both in training (maximal isometric force) and in wheelchair configurations (eg, camber angle). https://doi.org/10.1123/jsr.2017-0142 LinkedIn: https://www.linkedin.com/in/annemarie-de-witte-9582b154/ https://www.linkedin.com/in/moniqueberger/ https://www.linkedin.com/in/rienkvdslikke/

A new approach to observe the radiative decay of the $^{229}$Th nuclear isomer, and to determine its energy and radiative lifetime, is presented. Situated at a uniquely low excitation energy, this nuclear state might be a key ingredient for the development of a nuclear clock, a nuclear laser and the search for time variations of the fundamental constants. The isomer's $\gamma$ decay towards the ground state will be studied with a high-resolution VUV spectrometer after its production by the $\beta$ decay of $^{229}$Ac. The novel production method presents a number of advantages asserting its competitive nature with respect to the commonly used $^{233}$U $\alpha$-decay recoil source. In this paper, a feasibility analysis of this new concept, and an experimental investigation of its key ingredients, using a pure $^{229}$Ac ion beam produced at the ISOLDE radioactive beam facility, is reported., Comment: 11 pages, 5 figures, 2 tables

The first 2+ and 3- states of the doubly magic nucleus Sn132 are populated via safe Coulomb excitation employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the highly efficient MINIBALL array. The Sn132 ions are accelerated to an energy of 5.49 MeV/nucleon and impinged on a Pb206 target. Deexciting γ rays from the low-lying excited states of the target and the projectile are recorded in coincidence with scattered particles. The reduced transition strengths are determined for the transitions 0g.s.+→21+, 0g.s.+→31-, and 21+→31- in Sn132. The results on these states provide crucial information on cross-shell configurations which are determined within large-scale shell-model and Monte Carlo shell-model calculations as well as from random-phase approximation and relativistic random-phase approximation. The locally enhanced B(E2;0g.s.+→21+) strength is consistent with the microscopic description of the structure of the respective states within all theoretical approaches. The presented results of experiment and theory can be considered to be the first direct verification of the sphericity and double magicity of Sn132. (Less)

International audience; A Coulomb excitation campaign on $^{106,108,110}$Sn at 4.4–4.5 MeV/u was launched at the HIE-ISOLDE facility at CERN. Larger excitation cross sections and γ-ray statistics were achieved compared to previous experiments at ∼2.8 MeV/u. More precise $(B(E2;0_{1}^{ + } \to 2_{1}^{ + }))$ values, lifetimes of states via the Doppler shift attenuation method, and new $(B(E2;0_{1}^{ + } \to 2_{x}^{ + })), (B(E2;2_{1}^{ + } \to 4_{1}^{ + }))$ and $(Q(2_{1}^{ + }))$ values from the new Miniball data will be obtained and applied to test modern nuclear structure theories.

Measurements have been performed with scintillation crystals of LaBr3:Ce coupled to an array of Silicon Photomultipliers (SiPMs) in a 3 T magnetic field. The SiPMs were read out by digital data acquisition systems, including the GET electronics system. Inside of the B-field, energy resolution values of 3.82% FWHM at 661.7 keV are reported for a 1.5′′ cubic LaBr3:Ce crystal coupled to a 6 × 6 array of 6 × 6 mm2 SiPMs. No measurable degradation in energy resolution due to the presence of the strong magnetic field was observed.

The C-12(alpha,gamma)O-16 reaction plays a central role in astrophysics, but its cross section at energies relevant for astrophysical applications is only poorly constrained by laboratory data. The reduced a width, gamma(11), of the bound 1(-) level in O-16 is particularly important to determine the cross section. The magnitude of gamma(11) is determined via sub-Coulomb a-transfer reactions or the beta-delayed a decay of N-16, but the latter approach is presently hampered by the lack of sufficiently precise data on the beta-decay branching ratios. Here we report improved branching ratios for the bound 1(-) level [b(beta,11) = (5.02 +/- 0.10) x 10(-2)] and for beta-delayed alpha emission [b(beta alpha) = (1.59 +/- 0.06) x 10(-5)]. Our value for b(beta alpha) is 33% larger than previously held, leading to a substantial increase in gamma(11). Our revised value for gamma(11) is in good agreement with the value obtained in a-transfer studies and the weighted average of the two gives a robust and precise determination of gamma(11), which provides significantly improved constraints on the C-12(alpha,gamma) cross section in the energy range relevant to hydrostatic He burning.