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An in-beam study has been performed to further investigate the known isomeric decays and to identify T = 1 excited states in the medium-heavy N = Z = 33 nucleus 66As. The fusion-evaporation reaction 40Ca(28Si,pn)66As was employed at beam energies of 75 and 83 MeV. The half-lives and ordering of two known isomeric states in 66As have been determined with improved accuracy. In addition, several prompt γ-ray transitions from excited states, both bypassing and decaying to the isomeric states in 66As, have been observed. Most importantly, candidates for the 4+ → 2+ and 6+ → 4+ transitions in the T = 1 band have been identified. The results are compared with shell-model calculations using the modern JUN45 interaction in the pf5/2g9/2 model space. [ABSTRACT FROM AUTHOR]

Decays from isomeric states in the neutron-deficient N = 73 nuclei 132Pr and 130La have been observed for the first time. Half-lives of 486(70) ns and 2.46(4) μs were measured for two isomeric states in 132Pr. The decay from the 486 ns (8-) isomer has been interpreted as a hindered E1 transition from the bandhead state of the excited πh11/2 ⊗ vg7/2 configuration. The decay from the 2.5 μs (8+) isomer is consistent with the Weisskopf estimate for a low-energy E2 transition. An analogous 0.74(3) μs decay from an (8+) isomer in the neighboring isotone 130La has also been observed which similarly can be explained if the transition has E2 character. The Weisskopf interpretation for the isomer hindrance is strengthened by the lack of evidence for shape or K isomerism due to the γ-soft shapes predicted by configuration-constrained potential-energy-surface calculations. [ABSTRACT FROM AUTHOR]

Lifetime measurements have been made in the neutron-deficient nucleus 109Te using the coincident recoil distance Doppler-shift method. The experimental B(E2) values have been compared with state-of-the-art shellmodel calculations using the monopole-corrected realistic charge-dependent Bonn nucleon-nucleon potential. Lifetimes in the vh11/2 band are consistent with an interpretation based on the deformation driving properties of a single valence neutron outside of the even-even tellurium core and highlight the unexpected presence of collective behavior as the Ν = 50 shell closure is approached. Lifetime measurements for the low-lying positive-parity states also appear to correlate well with shell-model calculations. In addition, a comparison with the proton-unbound nucleus 109I suggests that the presence of a single decoupled valence proton affects the total measured B(E2) strengths in a manner that is not currently well understood. [ABSTRACT FROM AUTHOR]

Lifetimes of the low-lying excited states in the very neutron-deficient nucleus 175Au have been measured by the recoil-distance Doppler-shift method using γ-ray spectra obtained with the recoil-decay tagging technique. Transition quadrupole moments and reduced transition probabilities extracted for this odd-Z nucleus indicate the existence of three different shapes and the competition between collective and noncollective structures. [ABSTRACT FROM AUTHOR]

Weakly populated band structures have been established in 156Er at low to medium spins, following the 114Cd(48Ca,6nγ) reaction at 215 MeV. High-fold γ-ray coincidence data were recorded in a high-statistics experiment with the Gammasphere spectrometer. Bands built on the second 0+ and 2+ (γ-vibrational) states have been established. A large energy staggering between the even- and odd-spin members of the γ-vibrational band suggests a γ-soft nature of this nucleus. An additional band is discussed as being based on a rotationally aligned (πh9/2, f7/2)² structure, coexisting with the systematically observed, more favorable (υi3/2)² aligned structure seen in this mass region. [ABSTRACT FROM AUTHOR]

States above the known Kπ=8- 6 μs isomer in 138Gd have been populated with the 106Cd(36Ar,2p2n) reaction at a beam energy of 180 MeV at the University of Jyväskylä, Finland. The recoil-isomer tagging technique was utilized to correlate delayed γ-ray decays, detected in the GREAT focal plane spectrometer, with prompt decays measured in the JUROGAM II spectrometer at the target position. The lifetime of the Kπ=8- isomeric state has been remeasured as 6.2(2) μs. Two high-lying strongly coupled bands have been established with Kπ⩾12-. Potential-energy surface calculations, in conjunction with g factor measurements, reveal that they are built upon four-quasiparticle structures comprising two-quasineutron plus two-quasiproton configurations. The short half-life or lack of hindrance for the decays from these four-quasiparticle band-head states is reasoned to be a consequence of increased triaxial deformation and mixing due to the high density of states relative to the lower two-quasiparticle 6-μs isomeric state. [ABSTRACT FROM AUTHOR]

The emergence of ambient ionization techniques and their combination with smaller, cheaper mass spectrometers is beginning to make real the possibility of mass spectrometry measurements being made routinely outside of traditional laboratory settings. Here, we describe the development of an atmospheric solids analysis probe (ASAP) source for a commercially available miniaturized, single-quadrupole mass spectrometer and subsequent modification of the instrument to allow it to run as a deployable system; we further go on to describe the application of this instrument to the identification of the contents of drug seizures. For the drug seizure analysis, a small quantity of the material (powder, tablet, resin, etc.) was dissolved in ethanol and shaken to extract the analytes, the resulting solutions were then sampled by dipping a sealed glass capillary into the solution prior to analysis by ASAP-MS. Identification of the contents of the seizures was carried out using a NIST searching approach utilizing a bespoke spectral library containing 46 compounds representative of those most commonly encountered in UK forensic laboratories. In order to increase confidence in identification the library sample and subsequent analyses were carried out using a four-channel acquisition method; each channel in this method used a different cone voltage (15, 30, 50, and 70 V) inducing differing levels of in-source fragmentation in each channel; the match score across each channel was then used for identification. Using this developed method, a set of 50 real-life drug samples was analyzed with each of these being identified correctly using the library searching method.

Purpose: To characterize player core temperature (Tc) across two separate World Rugby Sevens Series (WRSS) tournaments in temperate and warm environments., Methods: Tc was collected in seventeen playing members of one men's team competing at the Singapore (n = 12) and London (n = 11) WRSS tournaments. Exertional heat illness (EHI) symptoms, cooling strategy use, playing minutes and wet blub globe temperature (WBGT) were also collected. Linear mixed models and magnitude-based inferences assessed differences in Tc between all periods within-and between tournaments and were also used to assess the effect of WBGT and playing minutes on Tc., Results: Several players experienced Tc in excess of 38°C during warm-ups and 39°C during games. The highest mean Tc values were observed in the final game on all days and in Singapore Day Two, there were substantial game-on-game increases in mean Tc. These Tc responses were associated with playing minutes (effect size; ±90% CL = 0.38; ±0.20), although the effect of WBGT was trivial and unclear. Further, there were no differences in Tc between the two tournaments in the different environments. Despite high individual peak Tc values (Singapore 39.9°C; London 39.6°C); no signs/symptoms of EHI were reported, voluntary post-game cooling usage was minimal, and pre- and mid-cooling strategies were not implemented., Conclusions: During WRSS matches, peak Tc values approached thresholds associated with EHI (>40°C) and exceeded those demonstrated to reduce repeated sprint performance (>39°C). Practitioners may consider the use of compatible cooling and heat acclimation strategies to minimize Tc increase and maximize player preparedness and recovery.

Fowler, PM, Murray, A, Farooq, A, Lumley, N, and Taylor, L. Subjective and objective responses to two rugby sevens world series competitions. J Strength Cond Res 33(4): 1043-1055, 2019-The purpose was to examine the utility of subjective and objective measures of player preparedness, interpreted at both group level and individual level, during 2 consecutive competitions of the World Rugby Sevens Series (WRSS). Subjective (sleep, energy, and muscle soreness ratings) and objective (heart rate [HR] at rest [HRREST] and in response to submaximal exercise [HREX]) measures were obtained from 16 male rugby 7s players from 1 team for 3 consecutive days (D1-3) at home (HOME) and on arrival at 4 tournament (T1-4) locations (T1-New Zealand; T2-USA; T3-Hong Kong; and T4-Tokyo) across 2 WRSS competitions (2 tournaments per competition) separated by 1 month. At a group level, energy ratings were significantly lower in T2 and T4 compared with HOME, and on D1 T2 compared with D1 T1 (p ≤ 0.05). Greatest variability in subjective ratings was observed during T1 and T3 at an individual level, particularly for sleep quality. Although at a group level HRREST and HREX significantly decreased in T1-4 compared with HOME (p ≤ 0.05), there was only a ∼50% agreement between the direction of change in HR indices at an individual level. Results from this study suggest that relocation between tournaments within WRSS competitions disrupts player preparedness measures to the largest degree. Hence, this period could be targeted by practitioners with appropriate recovery and/or sleep-promoting interventions or modulation of match-/training-load. Moreover, subjective rather than objective measures seem to be of greater use to inform player preparedness decision making, particularly at an individual level compared with a group level.

Rugby sevens, a sport new to the Olympics, features high-intensity intermittent running and contact efforts more than short match durations, normally 6 times across 2 to 3 d in a tournament format. Elite rugby sevens seasons often include over a dozen competitive tournaments over less than 9 months, demanding deliberate and careful training-stress balance and workload management alongside development of the necessary physical qualities required for competition. Focus on running and repeated power skills, strength, and match-specific conditioning capacities is advised. Partial taper approaches in combination with high-speed running (>5 m/s from GPS measures) before and between tournaments in succession may reduce injury rates and enhance performance. In a sport with substantial long-haul intercontinental travel and repetitive chronic load demands, management of logistics including nutrition and recovery is inclusive of the formula for success in the physical preparation of elite rugby sevens athletes.