Motor skill competence and moderate- and vigorous-intensity physical activity: a linear and non-linear cross-sectional analysis of eight pooled trials.

BACKGROUND: Few studies have examined the relationship between motor skill competence and device-measured physical activity in large samples and none have used non-linear modelling. This study assessed the linear and non-linear associations between motor skill competence and physical activity in children using pooled data from eight studies. METHODS: Cross-sectional ActiGraph accelerometer and motor skills competence data from 988 children (50.8% boys) aged 3-11 years were included. Total, object control and locomotor skill competence were assessed using the Test of Gross Motor Skill Development. Linear mixed models were fitted to examine linear associations between motor skill competence and physical activity. Then, restricted cubic splines models were used to assess potential non-linear relationships. Interactions by sex and age were assessed. RESULTS: There was evidence of positive linear associations between total skill, and object control and locomotor skills, with moderate- and vigorous-intensity physical activity; however, the associations with total skill competence and object control better fitted a non-linear model. Non-linear models indicated associations were positive but relatively weak in the low to mid ranges of TGMD/object control scores but at high ranges (~ > 70 out of 100/ and ~ 35 out of 50) the association strength increased for both moderate- and vigorous-intensity physical activity. There were sex interactions for locomotor skills only, specifically for vigorous activity with boys having a stronger positive association than girls. CONCLUSIONS: There appears to be a threshold for object control skill proficiency that children need to reach to enhance their physical activity levels which provides support for a motor skill "proficiency barrier". This provides a tangible benchmark for children to achieve in motor competence programs.

Scale-up of the Internet-based Professional Learning to help teachers promote Activity in Youth (iPLAY) intervention: a hybrid type 3 implementation-effectiveness trial.

BACKGROUND: Whole-of-school programs have demonstrated success in improving student physical activity levels, but few have progressed beyond efficacy testing to implementation at-scale. The purpose of our study was to evaluate the scale-up of the 'Internet-based Professional Learning to help teachers promote Activity in Youth' (iPLAY) intervention in primary schools using the RE-AIM framework. METHODS: We conducted a type 3 hybrid implementation-effectiveness study and collected data between April 2016 and June 2021, in New South Wales (NSW), Australia. RE-AIM was operationalised as: (i) Reach: Number and representativeness of students exposed to iPLAY; (ii) Effectiveness: Impact of iPLAY in a sub-sample of students (n = 5,959); (iii) Adoption: Number and representativeness of schools that received iPLAY; (iv) Implementation: Extent to which the three curricular and three non-curricular components of iPLAY were delivered as intended; (v) Maintenance: Extent to which iPLAY was sustained in schools. We conducted 43 semi-structured interviews with teachers (n = 14), leaders (n = 19), and principals (n = 10) from 18 schools (11 from urban and 7 from rural locations) to determine program maintenance. RESULTS: Reach: iPLAY reached ~ 31,000 students from a variety of socio-economic strata (35% of students were in the bottom quartile, almost half in the middle two quartiles, and 20% in the top quartile). EFFECTIVENESS: We observed small positive intervention effects for enjoyment of PE/sport (0.12 units, 95% CI: 0.05 to 0.20, d = 0.17), perceptions of need support from teachers (0.26 units, 95% CI: 0.16 to 0.53, d = 0.40), physical activity participation (0.28 units, 95% CI: 0.10 to 0.47, d = 0.14), and subjective well-being (0.82 units, 95% CI: 0.32 to 1.32, d = 0.12) at 24-months. Adoption: 115 schools received iPLAY. IMPLEMENTATION: Most schools implemented the curricular (59%) and non-curricular (55%) strategies as intended. Maintenance: Based on our qualitative data, changes in teacher practices and school culture resulting from iPLAY were sustained. CONCLUSIONS: iPLAY had extensive reach and adoption in NSW primary schools. Most of the schools implemented iPLAY as intended and effectiveness data suggest the positive effects observed in our cluster RCT were sustained when the intervention was delivered at-scale. TRIAL REGISTRATION: ACTRN12621001132831.

Dietary outcomes of overweight fathers and their children in the Healthy Dads, Healthy Kids community randomised controlled trial.

BACKGROUND: Few studies have examined dietary intake changes following a weight loss intervention in fathers and the association between father-child dietary intakes. The present study aimed to: (i) evaluate the change in dietary intake in overweight fathers randomised to a family-based lifestyle intervention [Healthy Dads Healthy Kids (HDHK)] versus controls and (ii) investigate whether an association exists between father-child dietary intakes. METHODS: A secondary analysis was conducted of father-child baseline and 3-month post-intervention data (n = 93) collected in the HDHK community randomised controlled trial. Intention-to-treat linear mixed models were used to assess dietary changes by group, time (baseline and 3-month) and the group-by-time interaction. Cohens d was used to determine effect sizes. RESULTS: Significant group-by-time effects (all P < 0.05) favouring fathers in the intervention group were identified for total daily energy intake (-1956 kJ, d = 0.74), total sugars (-45 g, d = 0.63), sodium (-414 mg, d = 0.58) and % energy from nutrient-dense, core foods (+10.1%, d = 0.86), fruit (+2.4%, d = 0.71), vegetarian protein sources (+1.2%, d = 0.57), pre-packed snacks (+1.7%, d = 0.58) and sugar-sweetened beverages (-4.1%, d = 0.58). At baseline, positive correlations were observed between father-child intakes for a number of dietary variables, and significant correlations were observed between father-child change scores for % energy carbohydrate (r = 0.35, P = 0.023), % energy from fruit (r = 0.47, P = 0.002), vegetarian protein sources (r = 0.46, P = 0.002) and frequency of consuming meals with vegetables (r = 0.38, P = 0.012). CONCLUSIONS: The HDHK intervention successfully improved some aspects of father's dietary intakes compared to controls. The fathers' eating patterns also correlated with those of their children for several dietary variables. These novel data suggest that fathers can be targeted as agents of dietary change within obesity prevention and treatment programmes.

A pilot intervention to reduce postpartum weight retention and central adiposity in first-time mothers: results from the mums OnLiNE (Online, Lifestyle, Nutrition & Exercise) study.

BACKGROUND: Postpartum weight retention (PPWR) increases the risk for obesity and complications during subsequent pregnancies. Few interventions have been successful in limiting PPWR in mothers. The present study assessed the effectiveness of the mums OnLiNE (Online, Lifestyle, Nutrition & Exercise) intervention with respect to reducing PPWR and improving diet, physical activity and sedentary behaviour. METHODS: A subsample of first-time mothers enrolled in the Extended Melbourne Infant Feeding Activity and Nutrition Trial (InFANT Extend) completed the nonrandomised mums OnLiNE intervention. Women in the intervention (I) group (n = 28) received access to an online calorie tracking program, smartphone app, three telephone counselling calls with a dietitian and written material. Women in two comparison groups (CI and C2) (n = 48; n = 43) were from the control (C1) and intervention (C2) arms of InFANT Extend and received no additional support. Weight and waist circumference were measured objectively. Written surveys assessed diet and physical activity. Sedentary behaviour was self-reported. Linear and logistic regression assessed changes in outcomes between groups from 9 to 18 months postpartum. RESULTS: Mean PPWR decreased in the (I) group (-1.2 kg) and the C2 group (-1.2 kg), although the changes were not significant. Mean waist circumference for all groups exceeded recommendations at baseline but decreased to below recommendations for women in the (I) group (78.3 cm) and significantly for the (I) group (-6.4 cm) compared to C1 (-1.1 cm; P = 0.002) and C2 (-3.3 cm; P = 0.001). Changes in diet, physical activity or sedentary behaviour were not significant. CONCLUSIONS: The online intervention reported in the present study shows promise with respect to reducing waist circumference in postpartum women. Further evidence of strategies that may improve weight and related behaviours in this target group is needed.

Mothers and teenage daughters walking to health: using the behaviour change wheel to develop an intervention to improve adolescent girls' physical activity.

OBJECTIVES: The majority of adolescent girls fail to meet public health guidelines for physical activity. Engaging mothers in the promotion of physical activity for their daughters may be an important strategy to facilitate behaviour change. The aim of this study was to use the behaviour change wheel (BCW) framework to design the components of an intervention to improve adolescent girls' physical activity. STUDY DESIGN: Cross-sectional study to inform intervention development. METHODS: The BCW framework was used to (1) understand the behaviour, (2) identify intervention functions and (3) select content and implementation options. A circular development process was undertaken by the research team to collectively design the intervention in accordance with the steps recommended by the BCW. RESULTS: The BCW design process resulted in the selection of six intervention functions (education, persuasion, incentivization, training, modelling, enablement) and 18 behaviour change techniques delivered via group-based, face-to-face mode. Behaviour change technique groupings include: goals and planning; feedback and monitoring; social support; shaping knowledge; natural consequences; comparison of behaviour; associations; comparison of outcomes; reward and threat; identity; and, self-belief. CONCLUSIONS: The BCW process allowed an in-depth consideration of the target behaviours and provided a systematic framework for developing the intervention. The feasibility and preliminary efficacy of the programme will be examined.

The impact of critical event checklists on medical management and teamwork during simulated crises in a surgical daycare facility.

Although the incidence of major adverse events in surgical daycare centres is low, these critical events may not be managed optimally due to the absence of resources that exist in larger hospitals. We aimed to study the impact of operating theatre critical event checklists on medical management and teamwork during whole-team operating theatre crisis simulations staged in a surgical daycare facility. We studied 56 simulation encounters (without and with a checklist available) divided between an initial session and then a retention session several months later. Medical management and teamwork were quantified via percentage adherence to key processes and the Team Emergency Assessment Measure, respectively. In the initial session, medical management was not improved by the presence of a checklist (56% without checklist vs. 62% with checklist; p = 0.50). In the retention session, teams performed significantly worse without the checklists (36% without checklist vs. 60% with checklist; p = 0.04). We did not observe a change in non-technical skills in the presence of a checklist in either the initial or retention sessions (68% without checklist vs. 69% with checklist (p = 0.94) and 69% without checklist vs. 65% with checklist (p = 0.36), respectively). Critical events checklists do not improve medical management or teamwork during simulated operating theatre crises in an ambulatory surgical daycare setting.

Effects of a 'school-based' physical activity intervention on adiposity in adolescents from economically disadvantaged communities: secondary outcomes of the 'Physical Activity 4 Everyone' RCT.

BACKGROUND/OBJECTIVES: Obesity prevention during adolescence is a health priority. The 'Physical Activity 4 Everyone' (PA4E1) study tested a multi-component physical activity intervention in 10 secondary schools from socio-economically disadvantaged communities. This paper aimed to report the secondary outcomes of the study; to determine whether the intervention impacted on adiposity outcomes (weight, body mass index (BMI), BMI z-score), and whether any effect was moderated by sex, baseline BMI and baseline physical activity level, at 12 and 24 months. SUBJECTS/METHODS: A cluster randomised controlled trial was conducted in New South Wales, Australia. The school-based intervention included seven physical activity strategies targeting the following: curriculum (strategies to maximise physical activity in physical education, student physical activity plans, an enhanced school sport programme); school environment (physical activity during school breaks, modification of school policy); and parents and the community (parent engagement, links with community physical activity providers). Students' weight (kg), BMI and BMI z-score, were collected at baseline (Grade 7), 12 and 24 months. Linear Mixed Models were used to assess between-group mean difference from baseline to 12 and 24 months. Exploratory sub-analyses were undertaken according to three moderators of energy balance. RESULTS: A total of 1150 students (mean age=12 years) provided outcome data at baseline, 1051 (91%) at 12 months and 985 (86%) at 24 months. At 12 months, there were group-by-time effects for weight (mean difference=-0.90 kg (95% confidence interval (CI)=-1.50, -0.30), P<0.01) and BMI (-0.28 kg m-2 (-0.50, -0.06), P=0.01) in favour of the intervention group, but not for BMI z-score (-0.05 (-0.11; 0.01), P=0.13). These findings were consistent for weight (-0.62 kg (-1.21, 0.03), P=0.01) and BMI (-0.28 kg m-2 (-0.49, -0.06), P=0.01) at 24 months, with group-by-time effects also found for BMI z-score (-0.08 (-0.14; -0.02), P=0.02) favouring the intervention group. CONCLUSION: The PA4E1 school-based intervention achieved moderate reductions in adiposity among adolescents from socio-economically disadvantaged communities. Multi-component interventions that increase adolescents' engagement in moderate-to-vigorous physical activity (MVPA) may assist in preventing unhealthy weight gain.

Dietary restriction and exercise improve airway inflammation and clinical outcomes in overweight and obese asthma: a randomized trial.

BACKGROUND: Obesity and asthma are associated conditions; however, the mechanisms linking the two remain unclear. Few studies have examined the effects of weight loss on inflammation and clinical outcomes in obese-asthma. OBJECTIVE: To compare the effects of weight loss achieved by dietary restriction, exercise or combined dietary restriction and exercise on airway inflammation and clinical outcomes in overweight and obese adults with asthma. METHODS: Participants (n = 46; 54.3% female, body mass index (mean ± SD) 33.7 ± 3.5 kg/m(2) ) were randomized to complete a 10-week dietary, exercise or combined dietary and exercise intervention. Dual-energy x-ray absorptiometry was performed, the Juniper Asthma Control Questionnaire and Juniper Asthma Quality of Life Questionnaire completed and inflammatory markers, dietary intake and physical activity measured. The trial was registered with the Australian Clinical Trials Registry: ACTRN12611000235909. RESULTS: Retention was 82.6%. Mean ± SD weight loss was 8.5 ± 4.2%, 1.8 ± 2.6% and 8.3 ± 4.9% after the dietary, exercise and combined interventions respectively. Asthma control improved after the dietary (mean ± SD; -0.6 ± 0.5, P ≤ 0.001) and combined interventions (-0.5 ± 0.7, P = 0.040), whereas quality of life improved after the dietary [median (IQR); 0.9 (0.4, 1.3), P = 0.002], exercise [0.49 (0.03, 0.78), P = 0.037] and combined [0.5 (0.1, 1.0), P = 0.007] interventions. A 5-10% weight loss resulted in clinically important improvements to asthma control in 58%, and quality of life in 83%, of subjects. Gynoid adipose tissue reduction was associated with reduced neutrophilic airway inflammation in women [ß-coefficient (95% CI); 1.75 (0.02, 3.48), P = 0.047], whereas a reduction in dietary saturated fat was associated with reduced neutrophilic airway inflammation in males (r = 0.775, P = 0.041). The exercise intervention resulted in a significant reduction to sputum eosinophils [median (IQR); -1.3 (-2.0, -1.0)%, P = 0.028]. CONCLUSION AND CLINICAL RELEVANCE: This study suggests a weight-loss goal of 5-10% be recommended to assist in the clinical management of overweight and obese adults with asthma. The obese-asthma phenotype may involve both innate and allergic inflammatory pathways.

Development and evaluation of the Motivation to Limit Screen-time Questionnaire (MLSQ) for adolescents.

OBJECTIVE: The aim of this study was to design and evaluate a brief scale to assess adolescents' motivation to limit their screen-time using a self-determination theory (SDT) framework. METHODS: The development and evaluation of the Motivation to Limit Screen-time Questionnaire (MLSQ) involved three phases. In Phase 1, experts in SDT were asked to review the content validity of the MLSQ items. In Phase 2, adolescent boys (N=342, mean age=12.7 ±.5 years) completed the MLSQ and the factorial validity of the model was explored. In Phase 3, adolescent boys (N=48, mean age=14.3 ± 1.3 years) completed the MLSQ on two occasions separated by 1-week. Phases 2 and 3 were conducted in New South Wales, Australia in 2012. RESULTS: Twenty four SDT experts reviewed the original scale items. Validity coefficients associated with six of the original eight items exceeded the threshold value (V>.68, p<.01). In Phase 2, the revised three-factor (9-items) model provided a good fit to the data (SRMR=.07, CFI=.96). The intraclass correlation (ICC) values were .67 for amotivation and .70 and .82 for controlled and autonomous motivation, respectively. CONCLUSION: This study has provided preliminary evidence for the validity and reliability of the MLSQ in adolescent boys.

Can a Web-based food record accurately assess energy intake in overweight and obese women? A pilot study.

BACKGROUND: Innovative dietary intake measurement tools, such as web-based food records, are becoming increasingly available for self-monitoring. However, the accuracy of this method has not been well studied. This pilot study aimed to evaluate the accuracy of energy intake (EI) estimated by a web-based food record, by comparison with total energy expenditure (TEE) measured by doubly-labelled water (DLW) in overweight and obese women. METHODS: Total energy expenditure (TEE) was assessed in weight stable (±1 kg) women (n = 9), with a mean (SD) age of 34.5 (11.3) years and body mass index of 29.2 (1.4) kg m(-2) over 10 days using the DLW technique. All food and beverages were self-reported for 9-days using a web-based food record and mean daily EI calculated. Food record accuracy was assessed by calculating the absolute (EI - TEE) and percentage (EI/TEE × 100) differences between EI and TEE. Women were identified as under-reporters of EI based on the 95% confidence limits of the expected EI : TEE of 1. RESULTS: The mean (SD) self-reported EI was 8351 (1225) kJ day(-1) [1996 (293) kcal day(-1) ] and TEE was 10 648 (1774) kJ day(-1) [2545 (424) kcal day(-1) ]. The mean (SD) absolute difference in self-reported EI and TEE was -2301 (1535) kJ day(-1) [-550 (367) kcal day(-1) ], representing a mean reporting accuracy of 79.6% (14.1%), with four participants under-reporting EI. CONCLUSIONS: This pilot study highlights the opportunity for the use of the Internet as a novel medium for recording and assessing dietary intake. Although further research is needed in more diverse population groups, the accuracy of web-based food records for assessing EI appears to be consistent with other published dietary intake methods.

Preventing and treating childhood obesity: time to target fathers.

OBJECTIVE: To examine the long-term effects of having one overweight or obese parent on child weight status and determine whether these effects vary according to parent sex. DESIGN: Prospective study: Longitudinal Study of Australian Children (LSAC). SUBJECTS: Two-parent families (N=3285) from the LSAC were included if height and weight data were available for both parents and their child at the 2004 and 2008 time points. MEASUREMENTS: Child weight status category (healthy, overweight, obese) in 2008 when the child was aged 8-9 years. Regression modelling was used to investigate how self-reported parent weight status in 2004 influenced measured child weight status 4 years later. RESULTS: Parent body mass index (BMI) was significantly correlated with child BMI, but there was no evidence of sex-specific associations between parent and child BMI correlations. The results from the regression analysis showed that having an overweight or obese father, but a healthy weight mother, significantly increased the odds of child obesity (odds ratio: 4.18, 95% confidence interval (CI): 1.01-17.33 and odds ratio: 14.88, 95% CI: 2.61-84.77, respectively), but the reverse scenario (overweight or obese mother with a healthy weight father) was not a significant predictor of child overweight or obesity (odds ratio: 2.52, 95% CI: 0.38-16.71 and odds ratio: 2.56, 95% CI: 0.31-21.26, respectively). CONCLUSIONS: Children with overweight or obese fathers are at a higher risk of becoming obese. This suggests that interventions are urgently required to test the efficacy of treating overweight fathers as a key strategy for childhood obesity prevention and/or treatment.

Description and evaluation of a social cognitive model of physical activity behaviour tailored for adolescent girls.

The aim of this paper was to describe and test a social cognitive model of physical activity tailored for adolescent girls. Participants were 1518 girls (aged 13.6 ± 0.02 years) from 24 secondary schools in New South Wales, Australia. Useable accelerometer (≥10 hours day(-1) on at least 3 days) and questionnaire data were obtained from 68% of this sample (N = 1035). Participants completed questionnaires assessing psychological, behavioural, social and environmental correlates of activity. The theoretical model was tested using structural equation modelling in AMOS. The model explaining accelerometer counts per minute was an adequate-to-good fit to the data (Tucker-Lewis Index = 0.89, the comparative fit index = 0.97 and the root mean square of approximation = 0.098; 90% confidence interval = 0.075-0.122) but explained only 5% of the variance in activity. There were significant model pathways from self-efficacy (r = 0.11, P = 0.01), school environment (r = 0.07, P = 0.02) and physical self-worth (r = 0.07, P = 0.04) to accelerometer counts. Although the proposed model provided an adequate-to-good fit to the data, it explained a small portion of the variance. Shared method variance may explain the larger portions of variance explained in previous studies. Future studies are encouraged to evaluate theories of physical activity behaviour change using objective measures of physical activity.

The 'Healthy Dads, Healthy Kids' randomized controlled trial: efficacy of a healthy lifestyle program for overweight fathers and their children.

OBJECTIVE: To evaluate the feasibility and efficacy of the 'Healthy Dads, Healthy Kids' (HDHK) program, which was designed to help overweight fathers lose weight and be a role model of positive health behaviors for their children. DESIGN: Randomized controlled trial. PARTICIPANTS: A total of 53 overweight/obese men (mean (s.d.) age=40.6 (7.1) years; body mass index (BMI)=33.2 (3.9)) and their primary school-aged children (n=71, 54% boys; mean (s.d.) age=8.2 (2.0) years) were randomly assigned (family unit) to either (i) the HDHK program (n=27 fathers, n=39 children) or (ii) a wait-list control group (n=26 fathers, n=32 children). INTERVENTION: Fathers in the 3-month program attended eight face-to-face education sessions. Children attended three of these sessions. OUTCOMES: The primary outcome was fathers' weight. Fathers and their children were assessed at baseline, and at 3- and 6-month follow-up, for weight, waist circumference, BMI, blood pressure, resting heart rate (RHR), objectively measured physical activity and self-reported dietary intake. RESULTS: Intention-to-treat analysis revealed significant between-group differences at 6 months for weight loss (P<0.001), with HDHK fathers losing more weight (-7.6 kg; 95% confidence interval (CI) -9.2, -6.0; d=0.54) than control group fathers (0.0 kg; 95% CI -1.4, 1.6). Significant treatment effects (P<0.05) were also found for waist circumference (d=0.62), BMI (d=0.53), systolic blood pressure (d=0.92), RHR (d=0.66) and physical activity (d=0.91), but not for dietary intake. In children, significant treatment effects (P<0.05) were found for physical activity (d=0.74), RHR (d=0.51) and dietary intake (d=0.84). CONCLUSION: The HDHK program resulted in significant weight loss and improved health-related outcomes in fathers and improved eating and physical activity among children. Targeting fathers is a novel and efficacious approach to improving health behavior in their children.

Equal and opposite expert opinion. Airway obstruction caused by a retrosternal thyroid mass: management and prospective international expert opinion.

Anticipated problems with airway management during anaesthesia require careful planning, particularly when they involve a risk of airway obstruction. Advice may be sought from published literature (usually written by experts) or through direct communication with experts. More frequently, expert involvement is through retrospective review following patient harm. We present the case of a patient suffering from a retrosternal thyroid mass that was compressing her trachea in the midline and dividing it into two 2 × 3 mm lumens. After local discussion the patient underwent thyroidectomy. We invited international experts in anaesthetic airway management to review her case and submit their opinions regarding the best airway management for this difficult case. Opinions differed markedly, mirroring the published literature. Some experts specifically criticised techniques that, unbeknown to them, were proposed by others. The case raises issues about the nature of expert opinion that extends beyond this particular case. The nature and implications of expert opinion, when evidence is absent or conflicting, are discussed.

Efficacy of high-fidelity simulation debriefing on the performance of practicing anaesthetists in simulated scenarios.

BACKGROUND: Research into adverse events in hospitalized patients suggests that a significant number are preventable. The purpose of this randomized, controlled study was to determine if simulation-based debriefing improved performance of practicing anaesthetists managing high-fidelity simulation scenarios. METHODS: The anaesthetists were randomly allocated to Group A: simulation debriefing; Group B: home study; and Group C: no intervention and secondary randomization to one of two scenarios. Six to nine months later, subjects returned to manage the alternate scenario. Facilitators blinded to study group allocation completed the performance checklists (dichotomously scored checklist, DSC) and Global Rating Scale of Performance (GRS). Two non-expert raters were trained, and assessed all videotaped performances. RESULTS: Interim analysis indicated no difference between Groups B and C which were merged into one group. Seventy-four subjects were recruited, with 58 complete data sets available. There was no significant effect of group on pre-test scores. A significant improvement was seen between pre- and post-tests on the DSC in debriefed subjects (pre-test 66.8%, post-test 70.3%; F(1,57)=4.18, P=0.046). Both groups showed significant improvement in the GRS over time (F(1,57)=5.94, P=0.018), but no significant difference between the groups. CONCLUSIONS: We found a modest improvement in performance on a DSC in the debriefed group and overall improvement in both control and debriefed groups using a GRS. Whether this improvement translates into clinical practice has yet to be determined.

Charge transfer by electronic excitation: Direct measurement by high resolution spectroscopy in the gas phase.

We report a quantitative measurement of the amount of charge that is transferred when the single ammonia complex of the photoacid beta-naphthol (2HNA) is excited by light. The measurement was made by comparing the permanent electric dipole moments of cis-2HNA in its ground (S(0)) and excited (S(1)) states, determined by Stark-effect studies of its fully resolved S(1)<--S(0) electronic spectrum. While the increase in electron transfer from the donor (NH(3)) to the acceptor (2HN) upon excitation is small ( approximately 0.05e), it is sufficient to redshift the electronic spectrum of the complex by approximately 600 cm(-1) ( approximately 0.1 eV). Thereby explored is the incipient motion of the acid-base complex along the excited state (electron-coupled) proton transfer coordinate.

Push-pull molecules in the gas phase: stark-effect measurements of the permanent dipole moments of p-aminobenzoic acid in its ground and electronically excited states.

Stark effect measurements of the permanent electric dipole moments of p-aminobenzoic acid (PABA) in the gas phase are reported based on studies of its fully resolved S1<--S0 electronic spectrum in the presence of an electric field. Ground-state (S0) PABA has mu = 3.3 D, whereas excited-state (S1) PABA has mu = 4.4 D. Despite PABA's reputation as a "push-pull" molecule, the photon-induced change in both the magnitude and orientation of mu is relatively small. Possible reasons for this behavior are discussed.

The Big Breakfast Study: Chrono-nutrition influence on energy expenditure and bodyweight.

A growing body of evidence highlights the importance of the biological clock as a modulator of energy balance and metabolism. Recent studies in humans have shown that ingested calories are apparently utilised more efficiently in the morning than in the evening and this is manifest through improved weight loss, even under iso-energetic calorie intake. The mechanisms behind this enhanced morning energy metabolism are not yet clear, although it may result from behavioural adaptations or circadian driven variations in physiology and energy metabolism. A major objective of the newly funded Big Breakfast Study therefore is to investigate the mechanistic basis of this amplified morning thermogenesis leading to enhanced weight loss, by exploring behavioural and physiological adaptations in energy expenditure alongside the underlying circadian biology. This report briefly discusses the current research linking meal timing, circadian rhythms and metabolism; highlights the research gaps; and provides an overview of the studies being undertaken as part of the Medical Research Council-funded Big Breakfast Study.

G protein-coupled receptor 101 mRNA expression in the mouse brain: altered expression in the posterior hypothalamus and amygdala by energetic challenges.

GPCR101 is a recently identified orphan G protein-coupled receptor (GPCR) expressed abundantly in the human and mouse hypothalamus. In the absence of a ligand, a direct approach to determine the function(s) of this receptor is not possible. However, clues to the possible functions of GPCR101 may yield from information on the distribution of the receptor and the effect of in vivo manipulation upon the expression level of the receptor. In situ hybridisation on mouse brain sections revealed GPCR101 expression in a number of nuclei, including the amygdala, lateral parabrachial nucleus and nucleus of the solitary tract, as well as in the arcuate nucleus, posterior hypothalamus and paraventricular nucleus of the hypothalamus. Food-deprivation was found to increase GPCR101 mRNA level in the posterior hypothalamus and amygdala. In obese mice bearing the ob gene mutation, GPCR101 mRNA level decreased in the posterior hypothalamus and remained unaltered in the amygdala. By contrast, in both nuclei, GPCR101 mRNA level did not change significantly in obese ob/ob mice after intraperitoneal injection of leptin or in mice fed with a high fat diet. These data suggest that GPCR101 mRNA expression in the posterior hypothalamus and amygdala is regulated by a factor(s) other than leptin. Dual in situ hybridisation was used to establish the relationship between GPCR101 and neuropeptides expressed in the hypothalamus. In the arcuate nucleus, GPCR101 mRNA was expressed in approximately half of the population of neurones expressing the mRNA for the anorexigenic neuropeptide, pro-opiomelanocortin, which suggests a potential functional relationship.