SU(3) Quantum Spin Ladders as a Regularization of the CP(2) Model at Non-Zero Density: From Classical to Quantum Simulation

Quantum simulations would be highly desirable in order to investigate the finite density physics of QCD. $(1+1)$-d $\mathbb{C}P(N-1)$ quantum field theories are toy models that share many important features of QCD: they are asymptotically free, have a non-perturbatively generated massgap, as well as $\theta$-vacua. $SU(N)$ quantum spin ladders provide an unconventional regularization of $\mathbb{C}P(N-1)$ models that is well-suited for quantum simulation with ultracold alkaline-earth atoms in an optical lattice. In order to validate future quantum simulation experiments of $\mathbb{C}P(2)$ models at finite density, here we use quantum Monte Carlo simulations on classical computers to investigate $SU(3)$ quantum spin ladders at non-zero chemical potential. This reveals a rich phase structure, with single- or double-species Bose-Einstein "condensates", with or without ferromagnetic order

Acculturation and physical activity among immigrants: a systematic review

Aim: The acculturation process presents numerous challenges that could benefit or adversely affect immigrants' health practices. The goal of this review was to present a systematic summary of studies examining the relationship between acculturation and physical activity among immigrants and ethnic minority populations. Subjects and methods: Systematic review based on 44 original studies found in electronic databases (Psychinfo/Psyndex, Eric, Pubmed/Medline, Web of Science, SportDiscus). Studies were eligible if they were written in English, German or French, incorporated a measure of acculturation and physical activity, exercise, or sport as independent and dependent variables, and provided statistical information to judge the level of significance. The 44 studies found included 760,242 participants. A narrative synthesis was performed. Causality of effects was examined based on seven criteria: consistency, strength of associations, specificity of effects, temporality, gradient, plausibility and experimental evidence. Results: Acculturation was associated with higher leisure time physical activity in 57% of all studies (even after controlling for potential confounds), independent of participants' gender, age and ethnic background. The main limitations of this review are that findings were not weighted for sample size and that publication biases might have contributed to an overestimation of the relationships. Conclusion: Prevention programs aimed at stimulating participation in physical activity among immigrants should give priority to individuals with low acculturation levels and it should consider culturally specific beliefs and constraints. Additionally, prevention programs could make an effort to promote acculturation among immigrants. Future studies should use longitudinal designs which include objective assessments of physical activity and which use multidimensional and bidirectional definitions of acculturatio

Stress-buffering effects of physical activity and cardiorespiratory fitness on metabolic syndrome: A prospective study in police officers

Metabolic syndrome (MetS) is a worldwide health concern related to cardiovascular disease. Stress at work increases the risk for MetS, whereas physical activity and cardiorespiratory fitness (CF) have been shown to be potential buffers against stress. The aim of this study was to test the stress-buffering effects of physical activity and CF on the relationship between work stress and MetS. In a prospective study, we followed 97 police officers (mean age = 39.7 years; mean body mass index = 25.74 kg/m2) over one year and assessed MetS, as defined by the National Cholesterol Education Program Adult Treatment Panel III. Stress at work was measured with the Job Content Questionnaire, as well as the Effort-Reward Imbalance Questionnaire. Physical activity was assessed objectively via 7-day accelerometry. CF was assessed with the Astrand bicycle ergometer test. Hierarchical linear regression models were carried out to predict MetS at follow-up (mean overall MetS score = 1.22), after controlling for baseline levels and sociodemographic background (mean overall MetS score = 1.19). Higher CF levels were significantly associated with lower MetS risk at follow-up ( β = -.38). By contrast, no main effects were found for physical activity and work stress. However, high effort and demand were significantly correlated with increased blood pressure (effort: r = .23 for systolic blood pressure; r = .21 for diastolic blood pressure) and waist circumference (effort: r = .26; demand: r = .23). Moreover, no significant interaction effects occurred between work stress and CF/physical activity. The results emphasize the importance of high levels of CF in the prevention of MetS in police officers. Accordingly, provision of regular training opportunities and repeated CF testing should be considered as a strategy in overall corporate health promotion

O(N) Models with Topological Lattice Actions

A variety of lattice discretisations of continuum actions has been considered, usually requiring the correct classical continuum limit. Here we discuss "weird" lattice formulations without that property, namely lattice actions that are invariant under most continuous deformations of the field configuration, in one version even without any coupling constants. It turns out that universality is powerful enough to still provide the correct quantum continuum limit, despite the absence of a classical limit, or a perturbative expansion. We demonstrate this for a set of O(N) models (or non-linear $\sigma$-models). Amazingly, such "weird" lattice actions are not only in the right universality class, but some of them even have practical benefits, in particular an excellent scaling behaviour.Comment: 7 pages, LaTex, 4 figures, 1 table, talk presented at the 31st Symposium on Lattice Field Theor

The relation between sleep and pain among a non-clinical sample of young adults

Poor sleep is linked to poorer daily functioning and increased risk of psychiatric symptoms. With respect to pain, the relation is bi-directional; poor sleep exacerbates pain, while greater pain adversely affects sleep. Moreover, perception of pain is subject to cognitive-emotional processes. Surprisingly, no data are available from non-clinical samples of young adults. The aim of the present study was therefore to investigate the relation between sleep and pain as a function of quality of life and depressive symptoms in young adults. The direction of influence between sleep and pain was statistically tested with two different structural equation models (SEMs). A total of 862 participants (639 women, 223 men; mean age: 24.67; SD=5.91) completed a series of validated self-report questionnaires assessing sleep, quality of life, depressive symptoms and cognitive-emotional elaboration of pain. Sleep, pain, quality of life, and depressive symptoms were interrelated. The first SEM suggested both a direct and an indirect influence of pain on sleep, whereas the second SEM suggested that sleep had only an indirect influence on pain. Irrespective of the SEM, the relation between sleep and cognitive-emotional elaboration of pain was mediated by quality of life and depressive symptoms. For a non-clinical sample of young adults, findings did support the bi-directional relation between poor sleep and increased cognitive-emotional elaboration of pain, though other cognitive-emotional processes such as depressive symptoms and quality of life should be taken into accoun

Association of Exercise with Inhibitory Control and Prefrontal Brain Activity Under Acute Psychosocial Stress

Psychosocial stress has negative effects on cognition in adolescents. The aim of this study was to investigate whether physical exercise can buffer such effects on inhibitory control and associated cortical brain areas. Forty-two male high school students aged 16-20 years and with either low or high exercise levels performed a Stroop task under stress-free conditions and after the Trier Social Stress Test (TSST). Oxygenation of the dorsolateral prefrontal cortex (DLPFC) was measured with functional near-infrared spectroscopy. For inhibitory control, there was no significant primary effect of condition (; F; (1,40) = 1.09,; p; = 303.,; ηp²; = 0.027) and no significant condition × group interaction (; F; (1,40) = 2.40,; p; = 0.129,; ηp²; = 0.057). For DLPFC oxygenation, a significant primary effect of condition was observed (; F; (1,38) = 6.10,; p; = 0.018,; ηp²; = 0.138). However, the condition × group interaction (; F; (1,38) = 0.05,; p; = 0.823,; ηp²; = 0.001) remained not significant. Adolescents' exercise level was not associated with inhibitory control before and after stress. An impact of stress on a neurocognitive level was observed

The Influence of an Acute Exercise Bout on Adolescents' Stress Reactivity, Interference Control, and Brain Oxygenation Under Stress

Background:High psychosocial stress can impair executive function in adolescents,whereas acute exercise has been reported to benefit this cognitive domain. The aim ofthis study was to investigate whether an acute bout of aerobic exercise improves theinhibitory aspect of executive function and the associated dorsolateral prefrontal cortex(DLPFC) oxygenation when under stress.Methods:Sixty male high school students aged 16–20 years performed a Strooptask (baseline condition) and were randomly assigned to an exercise group (30 min onergometer at 70% of maximum heart rate) and a control group (30 min of reading).Subsequently, all participants underwent a modified Trier Social Stress Test, whichincluded a Stroop task under enhanced stress. The Stroop tasks in both conditionswere combined with functional near-infrared spectroscopy to record changes in DLPFCoxygenation in response to the tasks. Stress reactivity was measured with salivasamples (cortisol, alpha-amylase), heart rate monitoring, and anxiety scores.Results:All stress parameters indicated increases in response to the stressor(p<0.001), with higher alpha-amylase [t(58) =−3.45,p= 0.001,d= 1.93] andanxiety [t(58) =−2.04,p= 0.046,d= 0.53] reactions in the control compared to theexercise group. Controlling for these two parameters, repeated measures analyses ofcovariance targeting changes in Stroop interference scores showed no main effect ofstress [F(1,58) = 3.80,p= 0.056,ηp2= 0.063] and no stress×group interaction[F(1,58) = 0.43,p= 0.517,ηp2= 0.008]. Similarly, there was no main effect ofstress [F(1,58) = 2.38,p= 0.128,ηp2= 0.040] and no stress×group interaction[F(1,58) = 2.80,p= 0.100,ηp2= 0.047] for DLPFC oxygenation.Conclusion:Our study confirms potentially health-enhancing effects of acute exerciseon some of the physiological and psychological stress reactivity indicators. However,our data do not support the notion of an effect on interference control and DLPFCactivation under stress

Impact of aerobic exercise on sleep and motor skills in children with autism spectrum disorders - a pilot study

Prevalence rates of autism spectrum disorder (ASD) have increased dramatically in the last two decades. In addition to the core symptoms such as impaired communication, difficulties in social interaction, and restricted and stereotypical patterns of behavior and interests, poor sleep and motor skill (MS) deficits have also been observed in children with ASD. On the other hand, there is evidence that aerobic exercise training (AET) has a positive impact on sleep, and that specific training improves MSs. Accordingly, the aim of the present pilot study was to investigate to what extent a combination of AET and MS training (MST) would improve sleep and physical performance in a small sample of children with ASD.; Ten children with ASD (mean age: 10 years) took part in the study. After a thorough medical examination and psychiatric assessment, children participated in thrice-weekly 60-minute sessions of AET and MST lasting for 3 consecutive weeks. Sleep was assessed both objectively (sleep-encephalography [sleep-EEG]) and subjectively (parents' questionnaire). MSs were assessed via standardized test batteries. Parents completed sleep and mood logs, and ratings of mood.; Mild-to-moderate insomnia was reported in 70% of children. Compared to nights without previous AET and MS, on nights following AET and MS, sleep efficiency increased (d=1.07), sleep onset latency shortened (d=0.38), and wake time after sleep onset decreased for 63% of the sample (d=1.09), as assessed via sleep-EEG. Mood in the morning, as rated by parents, improved after three weeks (d=0.90), as did MSs (ball playing, balance exercise: ds>0.6).; The pattern of results of this pilot study suggests that regular AET and MST impact positively on sleep, MSs, and mood among children with ASD

Impact of aerobic exercise on sleep and motor skills in children with autism spectrum disorders&nbsp;&ndash;&nbsp;a pilot study

BACKGROUND: Prevalence rates of autism spectrum disorder (ASD) have increased dramatically in the last two decades. In addition to the core symptoms such as impaired communication, difficulties in social interaction, and restricted and stereotypical patterns of behavior and interests, poor sleep and motor skill (MS) deficits have also been observed in children with ASD. On the other hand, there is evidence that aerobic exercise training (AET) has a positive impact on sleep, and that specific training improves MSs. Accordingly, the aim of the present pilot study was to investigate to what extent a combination of AET and MS training (MST) would improve sleep and physical performance in a small sample of children with ASD. METHODS: Ten children with ASD (mean age: 10 years) took part in the study. After a thorough medical examination and psychiatric assessment, children participated in thrice-weekly 60-minute sessions of AET and MST lasting for 3 consecutive weeks. Sleep was assessed both objectively (sleep-encephalography [sleep-EEG]) and subjectively (parents’ questionnaire). MSs were assessed via standardized test batteries. Parents completed sleep and mood logs, and ratings of mood. RESULTS: Mild-to-moderate insomnia was reported in 70% of children. Compared to nights without previous AET and MS, on nights following AET and MS, sleep efficiency increased (d=1.07), sleep onset latency shortened (d=0.38), and wake time after sleep onset decreased for 63% of the sample (d=1.09), as assessed via sleep-EEG. Mood in the morning, as rated by parents, improved after three weeks (d=0.90), as did MSs (ball playing, balance exercise: ds>0.6). CONCLUSION: The pattern of results of this pilot study suggests that regular AET and MST impact positively on sleep, MSs, and mood among children with ASD