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1.
Phys Rev Lett ; 131(20): 202501, 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38039485

ABSTRACT

The changes in mean-squared charge radii of neutron-deficient gold nuclei have been determined using the in-source, resonance-ionization laser spectroscopy technique, at the ISOLDE facility (CERN). From these new data, nuclear deformations are inferred, revealing a competition between deformed and spherical configurations. The isotopes ^{180,181,182}Au are observed to possess well-deformed ground states and, when moving to lighter masses, a sudden transition to near-spherical shapes is seen in the extremely neutron-deficient nuclides, ^{176,177,179}Au. A case of shape coexistence and shape staggering is identified in ^{178}Au which has a ground and isomeric state with different deformations. These new data reveal a pattern in ground-state deformation unique to the gold isotopes, whereby, when moving from the heavy to light masses, a plateau of well-deformed isotopes exists around the neutron midshell, flanked by near-spherical shapes in the heavier and lighter isotopes-a trend hitherto unseen elsewhere in the nuclear chart. The experimental charge radii are compared to those from Hartree-Fock-Bogoliubov calculations using the D1M Gogny interaction and configuration mixing between states of different deformation. The calculations are constrained by the known spins, parities, and magnetic moments of the ground states in gold nuclei and show a good agreement with the experimental results.

2.
Phys Rev Lett ; 131(2): 022501, 2023 Jul 14.
Article in English | MEDLINE | ID: mdl-37505957

ABSTRACT

The ß decays from both the ground state and a long-lived isomer of ^{133}In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to ß, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant ß-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their ß decays selectively populate only a few isolated neutron unbound states in ^{133}Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark ß-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the ß decay of neutron-rich nuclei southeast of ^{132}Sn and will serve as a guide for future theoretical development aiming to describe accurately the key ß decays in the rapid-neutron capture (r-) process.

3.
Front Cardiovasc Med ; 10: 1190513, 2023.
Article in English | MEDLINE | ID: mdl-37288254

ABSTRACT

Cardiovascular diseases (CVDs) are the leading cause of death worldwide. Currently, cardiovascular disease risk algorithms play a role in primary prevention. However, this is complicated by a lack of powerfully predictive biomarkers that could be observed in individuals before the onset of overt symptoms. A key potential biomarker for heart disease is the vascular endothelial growth factor (VEGF-A), a molecule that plays a pivotal role in blood vessel formation. This molecule has a complex biological role in the cardiovascular system due to the processes it influences, and its production is impacted by various CVD risk factors. Research in different populations has shown single nucleotide polymorphisms (SNPs) may affect circulating VEGF-A plasma levels, with some variants associated with the development of CVDs, as well as CVD risk factors. This minireview aims to give an overview of the VEGF family, and of the SNPs reported to influence VEGF-A levels, cardiovascular disease, and other risk factors used in CVD risk assessments.

5.
Phys Rev Lett ; 130(20): 202501, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37267578

ABSTRACT

We demonstrate a new technique for obtaining fission data for nuclei away from ß stability. These types of data are pertinent to the astrophysical r process, crucial to a complete understanding of the origin of the heavy elements, and for developing a predictive model of fission. These data are also important considerations for terrestrial applications related to power generation and safeguarding. Experimentally, such data are scarce due to the difficulties in producing the actinide targets of interest. The solenoidal-spectrometer technique, commonly used to study nucleon-transfer reactions in inverse kinematics, has been applied to the case of transfer-induced fission as a means to deduce the fission-barrier height, among other variables. The fission-barrier height of ^{239}U has been determined via the ^{238}U(d,pf) reaction in inverse kinematics, the results of which are consistent with existing neutron-induced fission data indicating the validity of the technique.

6.
Health Promot Int ; 38(4)2023 Aug 01.
Article in English | MEDLINE | ID: mdl-35024852

ABSTRACT

Improving equity in women's health requires gender-specific and empowering approaches. However, health programs often disempower women by adopting a 'one-size-fits-all' approach that emphasizes diet, exercise and weight loss over other important aspects like sleep and mental wellbeing. This article reports on the design of Next Level Health (NLH), a program that aims to empower women through developing a wide range of health behaviors to support their holistic wellbeing. NLH is grounded by ethics, theory and evidence to support women to make achievable, sustainable changes that are relevant to their everyday lives. Women utilized the NLH framework to develop an integrative health routine across six domains: physical activity, sleep, nutrition, eating behavior, self-care and stress management. The framework guided them to set small, incremental goals that were adaptive to their needs and built from their existing circumstances. Participants reflected on their progress with a facilitator during monthly meetings, accessed a social media support page and received monthly text messages. Health programs remain an essential approach to improving women's health alongside community- and policy-level strategies. The development of NLH exemplifies how evidence may partner with modern health promotion values to inform relevant and ethical program design for women.


In western societies, health programs often focus on weight loss through exercise and diet to promote women's health. Such approaches disempower women by undervaluing important factors affecting their health like stress and sleep and narrow their scope for 'health success'. This article reports on the development of Next Level Health (NLH) that aims to help women gain greater health-related control by broadening their approach to health. The program is designed to support women to set small, achievable goals across six domains (physical activity, sleep, nutrition, eating behavior, self-care, and stress management) toward developing positive and sustainable health behaviors. Although women work with a facilitator each month to set goals, they are ultimately in control of formulating their health plans and their progression through NLH. Women can support each other by joining a community of other NLH participants through a social media group. NLH offers a novel program that is responsive to women's individual health needs and broadens their potential for health success.


Subject(s)
Health Status , Holistic Health , Female , Humans , New Zealand , Women's Health , Health Promotion
7.
Phys Rev Lett ; 129(17): 172701, 2022 Oct 21.
Article in English | MEDLINE | ID: mdl-36332266

ABSTRACT

The ß-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. ß-delayed two-neutron emission (ß2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak ß2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on ß-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

8.
Naturwissenschaften ; 109(5): 43, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-35969288

ABSTRACT

While foraging, eavesdropping predators home in on the signals of their prey. Many prey signal from aggregations, however, and predators already en route to attack one individual often encounter the signals of other prey. Few studies have examined whether eavesdropping predators update their foraging decisions by switching to target these more recently signaling prey. Switching could result in reduced localization errors and more current estimates of prey location. Conversely, assessing new cues while already in pursuit of another target might confuse or distract a predator. We tested whether fringed-lipped bats (Trachops cirrhosus) switch prey targets when presented with new cues mid-approach and examined how switching and the distance between simulated prey influence attack accuracy, latency, and prey capture success. During nearly 80% of attack flights, bats switched between túngara frog (Engystomops pustulosus) calls spaced 1 m apart, and switching resulted in lower localization errors. The switching rate was reduced, and the localization advantage disappeared for calls separated by 3 m. Regardless of whether bats switched targets, attacks were less accurate, took longer, and were less often successful when calls were spaced at larger distances, indicating a distraction effect. These results reveal that fringed-lipped bats attend to cues from non-targeted prey during attack flights and that the distance between prey alters the effectiveness of attacks, regardless of whether a bat switches targets. Understanding how eavesdropping predators integrate new signals from neighboring prey into their foraging decisions will lead to a fuller picture of the ways unintended receivers shape the evolution of signaling behavior.


Subject(s)
Chiroptera , Animals , Anura , Cues , Predatory Behavior
9.
Phys Rev Lett ; 128(11): 112501, 2022 Mar 18.
Article in English | MEDLINE | ID: mdl-35363028

ABSTRACT

Using the fusion-evaporation reaction ^{96}Ru(^{58}Ni,p4n)^{149}Lu and the MARA vacuum-mode recoil separator, a new proton-emitting isotope ^{149}Lu has been identified. The measured decay Q value of 1920(20) keV is the highest measured for a ground-state proton decay, and it naturally leads to the shortest directly measured half-life of 450_{-100}^{+170} ns for a ground-state proton emitter. The decay rate is consistent with l_{p}=5 emission, suggesting a dominant πh_{11/2} component for the wave function of the proton-emitting state. Through nonadiabatic quasiparticle calculations it was concluded that ^{149}Lu is the most oblate deformed proton emitter observed to date.

10.
J Biol Chem ; 298(5): 101899, 2022 05.
Article in English | MEDLINE | ID: mdl-35398354

ABSTRACT

The spinocerebellar ataxias (SCAs) are a class of incurable diseases characterized by degeneration of the cerebellum that results in movement disorder. Recently, a new heritable form of SCA, spinocerebellar ataxia type 48 (SCA48), was attributed to dominant mutations in STIP1 homology and U box-containing 1 (STUB1); however, little is known about how these mutations cause SCA48. STUB1 encodes for the protein C terminus of Hsc70 interacting protein (CHIP), an E3 ubiquitin ligase. CHIP is known to regulate proteostasis by recruiting chaperones via a N-terminal tetratricopeptide repeat domain and recruiting E2 ubiquitin-conjugating enzymes via a C-terminal U-box domain. These interactions allow CHIP to mediate the ubiquitination of chaperone-bound, misfolded proteins to promote their degradation via the proteasome. Here we have identified a novel, de novo mutation in STUB1 in a patient with SCA48 encoding for an A52G point mutation in the tetratricopeptide repeat domain of CHIP. Utilizing an array of biophysical, biochemical, and cellular assays, we demonstrate that the CHIPA52G point mutant retains E3-ligase activity but has decreased affinity for chaperones. We further show that this mutant decreases cellular fitness in response to certain cellular stressors and induces neurodegeneration in a transgenic Caenorhabditis elegans model of SCA48. Together, our data identify the A52G mutant as a cause of SCA48 and provide molecular insight into how mutations in STUB1 cause SCA48.


Subject(s)
Spinocerebellar Ataxias , Ubiquitin-Protein Ligases , Ubiquitin , Humans , Mutation , Spinocerebellar Ataxias/genetics , Spinocerebellar Ataxias/metabolism , Ubiquitin/genetics , Ubiquitin/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitination
11.
J Radiol Prot ; 42(2)2022 Mar 25.
Article in English | MEDLINE | ID: mdl-35226882

ABSTRACT

In the few years leading up to this research, CLEAPSS noticed a small but steadily increasing number of calls from UK schools regarding a red-brown discolouration on the surface of the foil of their radium source. There were no reports of this type of discolouration on foils of other radionuclides. CLEAPSS and the University of Liverpool collaborated to investigate the nature and cause of this discolouration and the likelihood that the foils were becoming unsafe. The evidence indicates that the discolouration is principally caused by some combination of silicon, sulfur and possibly lead from within the foil diffusing into the face layer. There is no indication currently that the face layers are fragmenting on these foils, but the longer-term integrity of the discoloured foils now becomes questionable. Given the age of the foils and the radiotoxicity of radium, the recommendation from this research is that discoloured foils should be taken out of service and disposed.


Subject(s)
Radium , Schools , United Kingdom
12.
OTJR (Thorofare N J) ; 41(2): 80-89, 2021 04.
Article in English | MEDLINE | ID: mdl-33393417

ABSTRACT

As chronic pain (CP) interferes with an individual's lifestyle by limiting meaningful activities and health-related quality of life (HRQoL), occupational therapy (OT) plays an important role in CP management interventions. This pilot study aimed to explore the influence of a 13-week French-Canadian Lifestyle Redesign® for CP. A mixed-methods research design including a preexperimental quantitative component pre-/posttest was used with 15 participants with fibromyalgia. Although pain remained unchanged after the intervention, improvements were observed in participants' engagement in meaningful activities (p < .01), life balance (p < .01), mental components of HRQoL (p < .01), depressive symptoms (p = .047), and pain self-efficacy (p < .01). After the intervention, phone interviews (n = 6) highlighted the participants' appreciation of the focus being placed on their daily routines and the development of a sense of belonging throughout the intervention. This study suggests the potential feasibility and benefits of an occupation-based approach in CP management.


Subject(s)
Pain Management , Quality of Life , Canada , Humans , Life Style , Pilot Projects
14.
Phys Rev Lett ; 125(19): 192501, 2020 Nov 06.
Article in English | MEDLINE | ID: mdl-33216605

ABSTRACT

The ß 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<82 quadrant of neutron-rich nuclei. While both negative and positive parity states with spin 0 and 1 are expected within the Q_{ß} window, only three negative parity states are populated directly in the ß decay. The data provide a unique test of the competition between allowed Gamow-Teller and Fermi, and first-forbidden ß decays, essential for the understanding of the nucleosynthesis of heavy nuclei in the rapid neutron capture process. Furthermore, the observation of the parity changing 0^{+}→0^{-}ß decay where the daughter state is core excited is unique, and can provide information on mesonic corrections of effective operators.

17.
Phys Rev Lett ; 124(6): 062502, 2020 Feb 14.
Article in English | MEDLINE | ID: mdl-32109128

ABSTRACT

The nuclei below lead but with more than 126 neutrons are crucial to an understanding of the astrophysical r process in producing nuclei heavier than A∼190. Despite their importance, the structure and properties of these nuclei remain experimentally untested as they are difficult to produce in nuclear reactions with stable beams. In a first exploration of the shell structure of this region, neutron excitations in ^{207}Hg have been probed using the neutron-adding (d,p) reaction in inverse kinematics. The radioactive beam of ^{206}Hg was delivered to the new ISOLDE Solenoidal Spectrometer at an energy above the Coulomb barrier. The spectroscopy of ^{207}Hg marks a first step in improving our understanding of the relevant structural properties of nuclei involved in a key part of the path of the r process.

18.
Phys Rev Lett ; 124(4): 042503, 2020 Jan 31.
Article in English | MEDLINE | ID: mdl-32058764

ABSTRACT

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.

19.
Int J Cardiol ; 305: 25-34, 2020 04 15.
Article in English | MEDLINE | ID: mdl-32008847

ABSTRACT

BACKGROUND: Recent evidence suggests that routine exercise-based cardiac rehabilitation (CR) may not lead to a substantial increase in estimated peak oxygen uptake (V̇O2peak). This could reduce the potential benefits of CR and explain why CR no longer improves patient survival in recent studies. We aimed to determine whether routine exercise-based CR increases V̇O2peak using gold-standard maximal cardiopulmonary exercise testing (CPET), and to quantify the exercise training stimulus which might be insufficient in patients undertaking CR. METHODS: We studied the effects of a routine, twice weekly, exercise-based CR programme for eight weeks (intervention group) compared with abstention from supervised exercise training (control group) in patients with coronary heart disease. The primary outcome was V̇O2peak measured using CPET. We also measured changes in body composition using dual X-ray absorptiometry, carotid intima-media thickness, hs-CRP and N-terminal pro B-type natriuretic peptide at baseline, 10 weeks and 12 months. We also calculated the Calibre 5-year all-cause mortality risk score. RESULTS: Seventy patients (age 63.1 SD10.0 years; BMI 29.2 SD4.0 kg·m-2; 86% male) were recruited (n = 48 intervention; n = 22 controls). The mean aerobic exercise training duration was 23 min per training session, and the mean exercise training intensity was 45.9% of heart rate reserve. V̇O2peak was 23·3 ml·kg-1·min-1 at baseline, and there were no changes in V̇O2peak between groups at any time point. The intervention had no effect on any of the secondary endpoints. CONCLUSION: Routine CR does not lead to an increase in V̇O2peak and is unlikely to improve long-term physiological outcomes.


Subject(s)
Cardiac Rehabilitation , Carotid Intima-Media Thickness , Exercise , Exercise Test , Exercise Therapy , Female , Humans , Male , Middle Aged , Oxygen Consumption
20.
Appl Radiat Isot ; 156: 108951, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31790976

ABSTRACT

With the advancement of high-precision radiotherapy and the increasing use of higher intensity beams, the risk to the patient increases should the radiotherapy machine malfunction. Hence more accurate treatment verification is required. In this paper we provide a solution for real-time monitoring of X-ray beams from radiotherapy linear accelerators using monolithic active pixel sensors. We show that leaf errors can be detected with high precision in static fields and IMRT step and shoot, and accurate leaf tracking is possible in Volumetric Modulated Arc Therapy. The prototype MAPS detector meets the criteria of 1% attenuation acceptable for clinical use.


Subject(s)
Radiotherapy, Intensity-Modulated/methods , Humans , Radiotherapy Planning, Computer-Assisted/methods , Silicon/chemistry
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