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Fusion cross sections have been measured in the 40Ca + 58Ni and 40Ca + 64Ni systems at energies around and below the Coulomb barrier. The 40Ca beam was delivered by the XTU Tandem accelerator of the Laboratori Nazionali di Legnaro and evaporation residues were measured at very forward angles with the LNL electrostatic beam deflector. Coupled-channels calculations were performed which highlight possible strong effects of neutron transfers on the fusion below the barrier in the 40Ca + 64Ni system. Microscopic time-dependent Hartree-Fock calculations have also been performed for both systems. Preliminary results are shown.

Barrier distribution for the 28Si+154Sm system has been extracted from large angle quasielastic scattering measurement to investigate the role of various channel couplings on fusion dynamics. The coupled channel calculations, including the collective excitation of the target and projectile, are observed to reproduce the experimental BD rather well. It seems that the role of neutron transfer, relative to collective excitation, is in fact weak in the 28Si+154Sm system even though it has positive Q-value for neutron transfer channels.

The nuclear fusion is a reaction to form a compound nucleus. It plays an important role in several circumstances in nuclear physics as well as in nuclear astrophysics, such as synthesis of superheavy elements and nucleosynthesis in stars. Here we discuss two recent theoretical developments in heavy-ion fusion reactions at energies around the Coulomb barrier. The first topic is a generalization of the Wong formula for fusion cross sections in a single-channel problem. By introducing an energy dependence to the barrier parameters, we show that the generalized formula leads to results practically indistinguishable from a full quantal calculation, even for light symmetric systems such as 12C+12C, for which fusion cross sections show an oscillatory behavior. We then discuss a semi-microscopic modeling of heavy-ion fusion reactions, which combine the coupled-channels approach to the state-of-the-art nuclear structure calculations for low-lying collective motions. We apply this method to subbarrier fusion reactions of 58Ni+58Ni and 40Ca+58Ni systems, and discuss the role of anharmonicity of the low-lying vibrational motions.

Superheavy nuclei exist solely due to quantum shell effects, which create a pocket in the potential-energy surface of the nucleus, thus providing a barrier against spontaneous fission. Determining the height of the fission barrier and its angular-momentum dependence is important to quantify the role that microscopic shell corrections play in enhancing and extending the limits of nuclear stability. In this talk, the first measurement of a fission barrier in the very heavy nucleus 254No will be presented.

We plan to perform large angle quasi-elastic scattering experiments using a 28Si beam on heavy targets in order to study the nuclear dynamics and structure effects. As a prelude to our first test experiment with a 154Sm target, we study here the existing fusion data for the same system through the barrier distribution.

Fusion cross sections have been measured in the 40Ca + 58Ni and 40Ca + 64Ni systems at beam energies ranging from Elab = 104.75 MeV to 153.5 MeV using the Laboratori Nazionali di Legnaro electrostatic deflector. Distributions of barriers have been extracted from the experimental data. Preliminary coupled channel calculations were performed and hints of effects of neutron transfers on the fusion below the barrier in the 40Ca + 64Ni are discussed.

The fusion barrier distribution has provided a nice representation for the channel coupling effects on heavy-ion fusion reactions at energies around the Coulomb barrier. Here we discuss how one can extract the same representation using the so called sum-of-differences (SOD) method with quasi-elastic scattering cross sections. In contrast to the conventional quasi-elastic barrier distribution, the SOD barrier distribution has an advantage in that it can be applied both to non-symmetric and symmetric systems. It is also the case that the correspondence to the fusion barrier distribution is much better than the quasi-elastic barrier distribution. We demonstrate its usefulness by studying 16O+144Sm, 58Ni+58Ni, and 12C+12C systems.

Recently, the barrier distribution (BD) for the 28Si+154Sm system has been measured by our group using the quasi-elastic scattering technique. Here, we present the results of coupled-channel calculations performed to reproduce the measured BD. The inelastic excitation of target and projectile alone explains the experimentally observed BD very well, even though the system studied has large positive Q-value for neutron transfer channels. Hence, the results reveal no significant influence of positive Q-value neutron transfer channels on fusion enhancement for the 28Si+154Sm system. [ABSTRACT FROM AUTHOR]

We discuss the role of channel coupling of 28Si on fusion mechanism with permanently deformed target 154Sm. To this end, we analyze the experimental quasi-elastic cross sections at a large backward angle and quasi-elastic barrier distribution for 28Si+154Sm system using the coupledchannels approach. While earlier studies have reported the rotational excitation of 28Si playing role on fusion with spherical and near spherical target nuclei, we find its vibrational excitation as origin of observed barrier distribution for 28Si+154Sm system. Our study also reveals significant influence of channel couplings on the surface diffuseness parameter of an inter-nuclear potential supporting the earlier observations. [ABSTRACT FROM AUTHOR]

The vast knowledge regarding the strong influence of quadrupole deformation β2 of colliding nuclei in heavy-ion sub-barrier fusion reactions inspires a desire to quest the sensitivity of fusion dynamics to higher order deformations, such as β4 and β6 deformations. However, such studies have rarely been carried out, especially for deformation of projectile nuclei. In this article, we investigated the role of β4 of the projectile nucleus in the fusion of the 28Si+92Zr system. We demonstrated that the fusion barrier distribution is sensitive to the sign and value of the β4 parameter of the projectile, 28Si, and confirmed that the 28Si nucleus has a large positive β4. This study opens an indirect way to estimate deformation parameters of radioactive nuclei using fusion reactions, which is otherwise difficult because of experimental constraints. [ABSTRACT FROM AUTHOR]

Background: The nuclear structure of colliding nuclei is known to influence the fusion process. Couplings of the relative motion to nuclear shape deformations and vibrations lead to an enhancement of the sub-barrier fusion cross section in comparison with the predictions of one-dimensional barrier penetration models. This enhancement is explained by coupled-channels calculations including these couplings. The sub-barrier fusion cross section is also affected by nucleon transfer channels between the colliding nuclei. Purpose: The aim of the present experiment is to investigate the influence of the projectile and target nuclear structures on the fusion cross sections in the 40Ca+58Ni and 40Ca+64Ni systems. Methods: The experimental and theoretical fusion excitation functions as well as the barrier distributions were compared for these two systems. Coupled-channels calculations were performed using the ccfull code. Results: Good agreement was found between the measured and calculated fusion cross sections for the 40Ca + 58Ni system. The situation is different for the 40Ca + 64Ni system where the coupled-channels calculations with no nucleon transfer clearly underestimate the fusion cross sections below the Coulomb barrier. The fusion excitation function was, however, well reproduced at low and high energies by including the coupling to the neutron pair-transfer channel in the calculations. Conclusions: The nuclear structure of the colliding nuclei influences the fusion cross sections below the Coulomb barrier for both 40Ca + 58,64Ni systems. Moreover, we highlighted the effect of the neutron pair-transfer channel on the fusion cross sections in 40Ca + 64Ni. [ABSTRACT FROM AUTHOR]

The study of the coupling to collective states of the 28Si projectile and 154Sm target in fusion mechanism is reported. Understanding such couplings is important as they influence the barrier height and the formation probability of the compound nuclei, which in turn may be related to the synthesis of superheavy elements in heavier systems. In the present work, before performing the coupled-channel calculations, we wish to obtain an experimental signature of coupling to projectile and target excitation through barrier distribution (BD) study. To this end, the BDs of the 28Si+154Sm and 16O+154Sm systems have been compared using existing fusion data, scaled to compensate for the differences between the nominal Coulomb barriers and the respective coupling strengths. However, the large error bars on the high-energy side of the fusion BD prevent any definite identification of such signatures. We have, therefore, performed a quasi-elastic (QE) scattering experiment for the heavier 28Si+154Sm system and compared its results with existing QE data for the 16O projectile. Since QE BDs are precise at higher energies, the comparison has shown that the BD of 28Si+154Sm is similar to that of 16O+154Sm to a large extent except for a peaklike structure on the higher energy side. The similarity shows that the 154Sm deformation plays a major role in the fusion mechanism of 28Si+154Sm system. The peaklike structure is attributed to 28Si excitation. In contrast with previous studies, it is found that a coupled-channel calculation with vibrational coupling to the first 2+ state of 28Si reproduces this structure rather well. However, an almost identical result is found with the rotational coupling scheme if one considers the large positive hexadecapole deformation of the projectile. A value around that given by Möller and Nix (β4≈0.25) leads to a strong cancellation in the re-orientation term that couples the 2+ state back to itself, making that state look vibrational in this process. Thus, unlike the existing fusion data, our new QE results contain subtle details about the fusion mechanism of 28Si+154Sm system. They even show a sensitivity to the 28Si hexadecapole deformation and hence may be capable of giving a physically reasonable estimate for β4 in an indirect way. [ABSTRACT FROM AUTHOR]

Introduction: Physical activity and exercise are movement behaviors that support the lifestyle management of overweight and obesity. However, home-based exercise programs are commonly generic, and inconsistently undertake a holistic approach to program design., Methods: This work applied the Behavior Change Wheel, supplemented with previously conducted interviews, to the development of a home-based exercise program, specifically for people living with overweight and obesity. This provided an understanding of the target behavior and identified a behavioral diagnosis. These findings were mapped onto the Capability, Opportunity, Motivation-Behavior model and Theoretical Domains Framework, identifying changes needed and corresponding intervention functions., Results: Suitable Behavior Change Techniques were identified, alongside Capability Opportunity Motivation-Behavior components needed to facilitate an increase in exercise behaviors, and five key intervention functions. This housed the delivery of 24 Behavior Change Techniques, including goal setting, feedback, monitoring and repetition., Conclusion: Applying the Behavior Change Wheel has enabled detailed development of a home-based exercise program for adults living with overweight and obesity., Competing Interests: The authors declare that there is no conflict of interest that has influenced this research at any stage., (© 2024 The Author(s). Obesity Science & Practice published by World Obesity and The Obesity Society and John Wiley & Sons Ltd.)

The involvement of people with lived experience in the design of exercise programmes is more likely to lead to a more needs-sensitive and population-specific intervention. There is limited evidence of the integration of people with lived experience, particularly regarding home-based exercise programmes for adults living with overweight and obesity, despite this being a population that would significantly benefit from a suitably tailored programme. Semi-structured interviews were virtually conducted to explore 20 participants' experiences of exercising at home and their preferences for the design of future home-based exercise programmes. Codes were generated through thematic analysis, highlighting considerations such as comfort within a home-based environment, a desire for social connection, and the integration of technology. Four corresponding themes were generated, encapsulating participants' choice reasoning for home-based exercise, difficulties of engaging in home-based exercise, undertaking and adhering to home-based exercise, and factors that constitute the perfect programme. Although the involvement of people with lived experience in research can be time-consuming, this process is fundamental to the design of an effective and efficacious programme. These findings will inform the design and development of a home-based exercise programme for adults living with overweight and obesity.

Admitting male and female patients to the same room compromises the safety of female patients and violates the rights of all patients. We demonstrate that mixed bedding is common (47.22% of admissions), increasing and disproportionately affects vulnerable older patients in a large New Zealand hospital from 2011 to 2019 (n = 160 048). Eliminating mixed bedding should be a priority for our hospital system., (© 2022 Royal Australasian College of Physicians.)

The COVID-19 pandemic has impacted the ability of people globally to consistently engage in their typical physical activity and exercise behaviour, contributing to the rising number of people living with overweight and obesity. The imposed government lockdowns and quarantine periods saw an increase in social media influencers delivering their own home-based exercise programmes, but these are unlikely to be an evidence-based, efficacious, long-term solution to tackle sedentary behaviour and increase physical activity. This rapid review aims to conceptualise home-based exercise and physical activity programmes, by extracting relevant programme characteristics regarding the availability of evidence and effectiveness of home-based exercise programmes. Fifteen studies met the inclusion criteria, of which there were varied reports of significant positive effects of the exercise programme on weight management and related outcomes. The two most common measures were Body Mass Index and body mass, as of which almost all reported a trend of post intervention reduction. Some programmes reported qualitative data, identifying barriers to physical activity and preferred programme components, highlighting a need to consider factors outside of physiological measures. The findings provide guidance and direction for the development of future home-based physical activity and exercise programmes for adults living with overweight and obesity., (Crown Copyright © 2022. Published by Elsevier Ltd. All rights reserved.)

Introduction: In 2010, the U.S. Coast Guard (USCG) led a clean-up response to the Deepwater Horizon (DWH) oil spill. Human studies evaluating acute and longer-term cardiovascular conditions associated with oil spill-related exposures are sparse. Thus, we aimed to investigate prevalent and incident cardiovascular symptoms/conditions in the DHW Oil Spill Coast Guard Cohort., Methods: Self-reported oil spill exposures and cardiovascular symptoms were ascertained from post-deployment surveys (n = 4,885). For all active-duty cohort members (n = 45,193), prospective cardiovascular outcomes were classified via International Classification of Diseases, 9th Edition from military health encounter records up to 5.5 years post-DWH. We used log-binomial regression to calculate adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs) in the cross-sectional analyses and Cox Proportional Hazards regression to calculate adjusted hazard ratios (aHR) and 95% CIs for incident cardiovascular diagnoses during 2010-2015 and stratifying by earlier (2010-2012) and later (2013-2015) time periods., Results: Prevalence of chest pain was associated with increasing levels of crude oil exposure via inhalation (aPR high vs. none  = 2.00, 95% CI = 1.16-3.42, p-trend = 0.03) and direct skin contact (aPR high vs. none  = 2.72, 95% CI = 1.30-5.16, p-trend = 0.03). Similar associations were observed for sudden heartbeat changes and for being in the vicinity of burning oil exposure. In prospective analyses, responders (vs. non-responders) had an elevated risk for mitral valve disorders during 2013-2015 (aHR = 2.12, 95% CI = 1.15-3.90). Responders reporting ever (vs. never) crude oil inhalation exposure were at increased risk for essential hypertension, particularly benign essential hypertension during 2010-2012 (aHR = 2.00, 95% CI = 1.08-3.69). Responders with crude oil inhalation exposure also had an elevated risk for palpitations during 2013-2015 (aHR = 2.54, 95% CI = 1.36-4.74). Cardiovascular symptoms/conditions aPR and aHR estimates were generally stronger among responders reporting exposure to both crude oil and oil dispersants than among those reporting neither., Conclusions: In this large study of the DWH oil spill USCG responders, self-reported spill clean-up exposures were associated with acute and longer-term cardiovascular symptoms/conditions., (Published by Elsevier Ltd.)

Background : There is wide discrepancy in how published research defines and reports home-based exercise programmes. Studies consisting of fundamentally different designs have been labelled as home-based, making searching for relevant literature challenging and time consuming. This issue has been further highlighted by an increased demand for these programmes following the COVID-19 pandemic and associated government-imposed lockdowns. Purpose : To examine what specifically constitutes home-based exercise by: (1) developing definitions for a range of terms used when reporting exercise and physical activity programmes and (2) providing examples to contextualise these definitions for use when reporting exercise and physical activity programmes. Methods : A literature search was undertaken to identify previous attempts to define home-based exercise programmes. A working document, including initial definitions and examples were developed, which were then discussed between six experts for further refinement. Results : We generated definitions for universal key terms within three domains (and subdomains) of programme design: location (home-based, community/centre-based, or clinical setting), prescription (structured or unstructured) and delivery (supervised, facilitated, or unsupervised). Examples for possible combinations of design terms were produced. Conclusions : Definitions will provide consistency when using reporting tools and the intention is to discuss the issues presented as part of a Delphi study. This is of paramount importance due to the predicted increase in emerging research regarding home-based exercise.

Background: Exercise referral schemes in England offer referred participants an opportunity to take part in an exercise prescription in a nonclinical environment. The aim of these schemes is to effect clinical health benefits, yet there is limited evidence of schemes' effectiveness, which could be due to the heterogeneity in design, implementation, and evaluation. Additionally, there has been no concerted effort to map program characteristics., Objective: To understand what key delivery approaches are currently used within exercise referral schemes in England., Methods: Across England, a total of 30 schemes with a combined total of 85,259 exercise referral scheme participants completed a Consensus on Exercise Reporting Template-guided questionnaire. The questionnaire explored program delivery, nonexercise components, and program management., Results: Results found that program delivery varied, though many schemes were typically 12 weeks in length, offering participants 2 exercise sessions in a fitness gym or studio per week, using a combination of exercises. Adherence was typically measured through attendance, with nonexercise components and program management varying by scheme., Conclusion: This research provides a snapshot of current delivery approaches and supports the development of a large-scale mapping exercise to review further schemes across the whole of the United Kingdom in order to provide evidence of best practice and delivery approaches nationwide.

Objectives: To examine if exercise referral schemes (ERSs) are associated with meaningful changes in physical activity in a large cohort of individuals throughout England, Scotland, and Wales from The National Referral Database., Methods: Data were obtained from 5246 participants from 12 different ERSs, lasting 6-12 weeks. The preexercise referral scheme and changes from the preexercise to the postexercise referral scheme in self-reported International Physical Activity Questionnaire scores were examined. A 2-stage individual patient data meta-analysis was used to generate the effect estimates., Results: For the pre-ERS metabolic equivalent (MET) minutes per week, the estimate (95% confidence interval [CI]) was 676 MET minutes per week (539 to 812). For the change in MET minutes per week, the estimate (95% CI) was an increase of 540 MET minutes per week (396 to 684). Changes in the total PA levels occurred as a result of increases in vigorous activity of 17 minutes (95% CI, 9 to 24), increases in moderate activity of 29 minutes (95% CI, 22 to 36), and reductions in sitting of -61 minutes (95% CI, -78 to -43), though little change in walking (-5 min; 95% CI, -14 to 5) was found., Conclusions: Most participants undergoing ERSs are already "moderately active." Changes in PA behavior associated with participation are through increased moderate to vigorous PA and reduced sitting. However, this was insufficient to change the International Physical Activity Questionnaire category, and the participants were still "moderately active."

Background: Exercise referral schemes within clinical populations may offer benefits for inactive and sedentary individuals, and improve and aid treatment of specific health disorders. This systematic review aims to provide an overview, and examine the impact, of exercise referral schemes in patients with cardiovascular, mental health, and musculoskeletal disorders. This review focuses on populations within the United Kingdom (UK) only, with an aim to inform national exercise referral policies and guidelines., Method: Data was collected from specific sources using validated methodology through PRISMA. Systematic searches were performed using Locate, PubMed, Scopus and Pro Quest: Public Health databases. Thirteen studies met inclusion criteria set for each sub group. This included that all studies aimed to prevent, observe, or decrease ill-health relating to the disorder, participants over the age of sixteen, and health disorders and outcomes were reviewed. All studies were conducted in the UK only., Results: In the 13 articles, a variety of modes and types of exercise were utilised. One-to-one supervised exercise sessions based in a gym environment were most frequently employed. Results showed that longer length schemes (20+ weeks) produced better health outcomes, and had higher adherence to physical activity prescribed, than those of shorter length (8-12 weeks). In patients referred with cardiovascular disorders, cardiovascular-related measures showed significant decreases including blood pressure. Schemes increased physical activity levels over the length of scheme for all disorders., Conclusion: Longer length schemes (20+ weeks) improved adherence to physical activity prescribed over the course of the scheme, and could support longer term exercise adherence upon completion, however additional research on larger samples should examine this further. An implication is that schemes currently recommended in guidelines do not tailor programmes to support long term adherence to exercise, which must be addressed. There is currently a lack of research examining programmes tailored to suit the individual's health conditions thus further research might allow providers to tailor delivery and build upon policy recommendations in the UK.

From a cycling paradigm, little has been done to understand the relationships between maximal isometric strength of different single joint lower body muscle groups and their relation with, and ability to predict PPO and how they compare to an isometric cycling specific task. The aim of this study was to establish relationships between maximal voluntary torque production from isometric single-joint and cycling specific tasks and assess their ability to predict PPO. Twenty male trained cyclists participated in this study. Peak torque was measured by performing maximum voluntary contractions (MVC) of knee extensors, knee flexors, dorsi flexors and hip extensors whilst instrumented cranks measured isometric peak torque from MVC when participants were in their cycling specific position (ISOCYC). A stepwise regression showed that peak torque of the knee extensors was the only significant predictor of PPO when using SJD and accounted for 47% of the variance. However, when compared to ISOCYC, the only significant predictor of PPO was ISOCYC, which accounted for 77% of the variance. This suggests that peak torque of the knee extensors was the best single-joint predictor of PPO in sprint cycling. Furthermore, a stronger prediction can be made from a task specific isometric task., (Copyright © 2017 Elsevier Ltd. All rights reserved.)