Higher physical fitness levels are associated with less language decline in healthy ageing

Healthy ageing is associated with decline in cognitive abilities such as language. Aerobic fitness has been shown to ameliorate decline in some cognitive domains, but the potential benefits for language have not been examined. In a cross-sectional sample, we investigated the relationship between aerobic fitness and tip-of-the-tongue states. These are among the most frequent cognitive failures in healthy older adults and occur when a speaker knows a word but is unable to produce it. We found that healthy older adults indeed experience more tip-of-the-tongue states than young adults. Importantly, higher aerobic fitness levels decrease the probability of experiencing tip-of-the-tongue states in healthy older adults. Fitness-related differences in word finding abilities are observed over and above effects of age. This is the first demonstration of a link between aerobic fitness and language functioning in healthy older adults

Influence of extended dynamics on phase transitions in a driven lattice gas

Monte Carlo simulations and dynamical mean-field approximations are performed to study the phase transition in a driven lattice gas with nearest-neighbor exclusion on a square lattice. A slight extension of the microscopic dynamics with allowing the next-nearest-neighbor hops results in dramatic changes. Instead of the phase separation into high- and low-density regions in the stationary state the system exhibits a continuous transition belonging to the Ising universality class for any driving. The relevant features of phase diagram are reproduced by an improved mean-field analysis.Comment: 3 pages, 3 figure

Digital Bridges Across Disciplinary, Practical and Pedagogical Divides: An Online Professional Master’s Program in Heritage Resource Management

Growth and diversification in heritage resource management (HRM) archaeology since the 1960s have created new demands for training the next generations of HRM leaders and for addressing persistent and counterproductive divisions between academic and applied archaeologies. The Simon Fraser University Department of Archaeology (SFU) has responded to these demands with an all-new, cohort-based, thesis-focused graduate program created by and for HRM professionals. The program’s target audience is HRM practitioners who hold Bachelor’s credentials, have initiated promising careers in HRM, and desire advanced, research-focused degrees to enable their professional capacity and upward mobility. The SFU program is structured and focused to provide intensive, predominantly online training in the four essential dimensions of HRM: law and policy, ethics and practice, business management, and research design and methods. The program has been successful through initial cohort cycles and in attracting HRM industry interest in collaboration. Industry-academic partnerships in cognate disciplines have proved effective in comparable circumstances but remain underdeveloped as bases for planning and delivering state-of-the-art training in applied archaeology and the broader field of HRM. Critical next steps in program development entail the identification of attributes of HRM futures desired by all or most HRM stakeholders and the collaborative pursuit of those desired futures

Effects of finite curvature on soliton dynamics in a chain of nonlinear oscillators

We consider a curved chain of nonlinear oscillators and show that the interplay of curvature and nonlinearity leads to a number of qualitative effects. In particular, the energy of nonlinear localized excitations centered on the bending decreases when curvature increases, i.e. bending manifests itself as a trap for excitations. Moreover, the potential of this trap is double-well, thus leading to a symmetry breaking phenomenon: a symmetric stationary state may become unstable and transform into an energetically favorable asymmetric stationary state. The essentials of symmetry breaking are examined analytically for a simplified model. We also demonstrate a threshold character of the scattering process, i.e. transmission, trapping, or reflection of the moving nonlinear excitation passing through the bending.Comment: 13 pages (LaTeX) with 10 figures (EPS

The CO2 stimulus duration and steady-state time point used for data extraction alters the cerebrovascular reactivity outcome measure

Cerebrovascular reactivity to carbon dioxide (CVR) is a common functional test to assess brain vascular health, though conflicting age and fitness effects have been reported. Studies have used different CO 2 stimulus durations to induce CVR and extracted data from different time points for analysis. Therefore, this study examined whether these differences alter CVR and explain conflicting findings. Eighteen healthy volunteers (24 5 years) inhaled CO ± 2 for four stimulus durations (1, 2, 4 and 5 min) of 5% CO 2 (in air) via the open-circuit Douglas bag method, in a randomized order. CVR data were derived from transcranial Doppler (TCD) measures of middle cerebral artery blood velocity (MCAv), with concurrent ventilatory sensitivity to the CO 2 stimulus (̇ V E,CO 2). Repeated measures ANOVAs compared CVR and ̇ V E,CO 2 measures between stimulus durations and steady-state time points. An effect of stimulus duration was observed (P = 0.002, í µí¼ 2 = = 0.140), with 1 min (P 0.010) and 2 min (P < 0.001) differing from 4 min, and 2 min differing from 5 min (P = 0.019) durations. ̇ V E CO , 2 sensitivity increased ∼3-fold from 1 min to 4 and 5 min durations (P < 0.001, í µí¼ 2 = 0.485). CVRs calculated from different steady-state time points within each stimulus duration were different (P < 0.001, í µí¼ 2 = = 0.454), specifically for 4 min (P 0.001) and 5 min (P P < 0.001), but not 2 min stimulus durations (= 0.273). These findings demonstrate that methodological differences alter the CVR measure

Effect of Pressure on Tiny Antiferromagnetic Moment in the Heavy-Electron Compound URu_2Si_2

We have performed elastic neutron-scattering experiments on the heavy-electron compound URu_2Si_2 for pressure P up to 2.8 GPa. We have found that the antiferrmagnetic (100) Bragg reflection below T_m ~ 17.5 K is strongly enhanced by applying pressure. For P < 1.1 GPa, the staggered moment mu_o at 1.4 K increases linearly from ~ 0.017(3) mu_B to ~ 0.25(2) mu_B, while T_m increases slightly at a rate ~ 1 K/GPa, roughly following the transition temperature T_o determined from macroscopic anomalies. We have also observed a sharp phase transition at P_c ~ 1.5 GPa, above which a 3D-Ising type of antiferromagnetic phase (mu_o ~ 0.4 mu_B) appears with a slightly reduced lattice constant.Comment: RevTeX, 4 pages, 4 eps figures, accepted for publication in Phys. Rev. Let

Accrual and drop out in a primary prevention randomised controlled trial: qualitative study

<p>Abstract</p> <p>Background</p> <p>Recruitment and retention of participants are critical to the success of a randomised controlled trial. Gaining the views of potential trial participants who decline to enter a trial and of trial participants who stop the trial treatment is important and can help to improve study processes. Limited research on these issues has been conducted on healthy individuals recruited for prevention trials in the community.</p> <p>Methods</p> <p>Semi-structured interviews with people who were eligible but had declined to participate in the Aspirin for Asymptomatic Atherosclerosis (AAA) trial (N = 11), and AAA trial participants who had stopped taking the trial medication (N = 11). A focus group with further participants who had stopped taking the trial medication (N = 6). (Total participants N = 28).</p> <p>Results</p> <p>Explanations for declining to participate could be divided into two groups: the first group were characterised by a lack of necessity to participate and a tendency to prioritise other largely mundane problems. The second group's concern was with a high level of perceived risk from participating.</p> <p>Explanations for stopping trial medication fell into four categories: side effects attributed to the trial medication; starting on aspirin or medication contraindicating to aspirin; experiencing an outcome event, and changing one's mind.</p> <p>Conclusions</p> <p>These results indicate that when planning trials (especially in preventive medicine) particular attention should be given to designing appropriate recruitment materials and processes that fully inform potential recruits of the risks and benefits of participation.</p> <p>Trial registration</p> <p>ISRCTN66587262</p

'The best thing for the baby': mothers' concepts and experiences related to promoting their infants' health and development

Mothers and pregnant women in contemporary western societies are at the centre of a web of expert and lay discourses concerning the ways they should promote and protect the health and development of their foetuses and infants. This article reports the findings from an Australian study involving interviews with 60 mothers. The findings explore in detail four topics discussed in the interviews related to pregnancy and caring for young infants: disciplining the pregnant body; promoting infants’ health; immunisation; and promoting infants’ development. It is concluded that the mothers were highly aware of their responsibilities in protecting their foetuses and infants from harm and promoting their health and development. They conceptualised the infant body as highly vulnerable and requiring protection from contamination. They therefore generally supported the idea of vaccination as a way of protecting their babies’ immature immune systems, but were also often ambivalent about it. The mothers were aware of the judgemental attitudes of others, including other mothers, towards their caring efforts and attempted to conform to the ideal of the ‘good mother’. The emotional dimensions of caring for infants and protecting their health are discussed in relation to the voluntary participation of mothers in conforming to societal expectations