The use of uniaxial accelerometry for the assessment of physical-activity-related energy expenditure: a validation study against whole-body indirect calorimetry.

Assessing the total energy expenditure (TEE) and the levels of physical activity in free-living conditions with non-invasive techniques remains a challenge. The purpose of the present study was to investigate the accuracy of a new uniaxial accelerometer for assessing TEE and physical-activity-related energy expenditure (PAEE) over a 24 h period in a respiratory chamber, and to establish activity levels based on the accelerometry ranges corresponding to the operationally defined metabolic equivalent (MET) categories. In study 1, measurement of the 24 h energy expenditure of seventy-nine Japanese subjects (40 (SD 12) years old) was performed in a large respiratory chamber. During the measurements, the subjects wore a uniaxial accelerometer (Lifecorder; Suzuken Co. Ltd, Nagoya, Japan) on their belt. Two moderate walking exercises of 30 min each were performed on a horizontal treadmill. In study 2, ten male subjects walked at six different speeds and ran at three different speeds on a treadmill for 4 min, with the same accelerometer. O2 consumption was measured during the last minute of each stage and was expressed in MET. The measured TEE was 8447 (SD 1337) kJ/d. The accelerometer significantly underestimated TEE and PAEE (91.9 (SD 5.4) and 92.7 (SD 17.8) % chamber value respectively); however, there was a significant correlation between the two values (r 0.928 and 0.564 respectively; P<0.001). There was a strong correlation between the activity levels and the measured MET while walking (r(2) 0.93; P<0.001). Although TEE and PAEE were systematically underestimated during the 24 h period, the accelerometer assessed energy expenditure well during both the exercise period and the non-structured activities. Individual calibration factors may help to improve the accuracy of TEE estimation, but the average calibration factor for the group is probably sufficient for epidemiological research. This method is also important for assessing the diurnal profile of physical activity.

When several queens reign: how polygyny affects social life in ants

Astract: The aim of this thesis was to investigate how the presence of multiple queens (polygyny) affects social organization in colonies of the ant Formica exsecta. This is important because polygyny results in reduced relatedness among colony members and therefore reflects a potential paradox for altruistic cooperation being explained by inclusive fitness theory. The reason for this is that workers in polygynous colonies rear no longer only their siblings (high inclusive fitness gain) but also more distantly ox even unrelated brood (low or no inclusive fitness gain). All research projects conducted in this thesis are novel and significant contributions to the understanding of the social evolution of insect societies. We used a mixture of experimental and observational methodologies in laboratory and field colonies of F. exsecta to examine four important aspects of social life that are impacted by polygyny. First, we investigated the influence of queen number on colony sex allocation and found that the number of queens present in a colony significantly affects colony sex ratio investment. The data were consistent with the queen-replenishment hypothesis, which is based on the observation that newly mated queens are often recruited back to their parental nest. According to this theory, colonies containing many queens should only produce males due to local resource competition (i.e. related queens compete for common resources), whereas colonies hosting few queens benefit most from producing new queens to ensure colony survival. Second, we examined how reproduction is partitioned among nestmate queens. We detected a novel pattern of reproductive partitioning whereby a high proportion of queens were completely specialized in the production of only a subset of offspring classes produced within a colony, which might translate into great differences in reproductive success between queens. Third, we could demonstrate that F. exsecta workers indiscriminately reared highly related and unrelated brood although such nepotistic behaviour (preferential rearing of relatives) would be predicted by inclusive fitness theory. The absence of nepotism is probably best explained by its negative effects on overall colony efficiency. Finally, we conducted a detailed population genetic analysis, which revealed that the genetic population structure is different for queens and workers. Our data were best explained with queens forming family-based groups (multicolonial population structure), whereas workers from several nests seemed to be grouped into larger unites (unicolonial population structure) with workers moving freely between neighbouring nests. Altogether, the presented work significantly increased our understanding of the complex organization of polygynous social insect colonies and shows how an important life history trait such as queen number affects social organization at various levels. Résumé: Le but de cette thèse était d'étudier comment la présence de plusieurs reines par colonie (polygynie) influence la vie sociale chez la fourmi Formica exsecta. Ce sujet est important parce que la polygynie chez les insectes sociaux présente un passible paradoxe au niveau de la théorie du "fitness inclusive". Ce paradoxe est basé sur le fait que les ouvrières n'élèvent plus uniquement leurs frères et soeurs (gain de "fitness inclusive" maximale), mais également des individus moins ou pas du tout apparentés (gain de "fitness inclusive" réduit ou absent). Tous les projets de recherche présentés au cours de cette thèse apportent une meilleure compréhension et connaissance au niveau de l'organisation des colonies chez les insectes sociaux. Nous avons employé des méthodes d'observation et de laboratoire afin de mettre en évidence des aspects importants de la vie sociale chez les fourmis influencés par la polygynie. Quatre aspects ont été caractérisés : (1) l'influence du nombre de reines sur le sexe ratio produit par la colonie. Nous avons démontré que les colonies contenant beaucoup de reines produisaient rarement des reines tandis que les colonies contenant peu de reines souvent investissaient beaucoup de ressources dans la production des reines. Ces résultats sont en accord avec la "queen-replenishment hypothesis" qui est basé sur l'observation que les nouvelles reines sont recrutées dans la colonie où elles étaient nées. Cette hypothèse postule que la production des reines est défavorable dans les colonies contenant beaucoup de reines, parce que ces reines apparentées, rentrent en compétition pour des ressources communes. Au contraire, la production des reines est favorable dans des colonies contenant peu de reines afin d'assurer la survie de la colonie ; (2) comment les reines dans une colonie répartissent leur reproduction. Nous avons mis en évidence un nouveau pattern de cette répartition où une grande proportion de reines est complètement spécialisée dans la production d'un seul type de couvain ce qui probablement aboutit à des différences significatives entre reines dans le succès reproducteur ; (3) la capacité des ouvrières à discriminer un couvain de soeur d'un couvain non apparenté. Les résultats ont montré que les ouvrières ne font pas de discrimination entre le couvain de soeur et le couvain non apparenté ce qui n'est pas en accord avec la théorie de la "fitness inclusive". Cette absence de discrimination est probablement due à des effets négatifs comme par exemple la diminution de la production du couvain; (4) la structure génétique d'une population de F. exsecta. Nous avons mis en évidence que la structure génétique entre des groupes de reines est significativement différente de la structure génétique entre des groupes d'ouvrières. Les données suggèrent que les reines forment des groupes basés sur une structure familiale tandis que les ouvrières sont groupées dans des unités plus grandes.

Spontaneous 24-h GHRELIN secretion pattern in fasting subjects : maintenance of a meal-related pattern

RESUME OBJECTIF: Outre la stimulation de la sécrétion d'hormone de croissance, la ghréline cause une prise pondérale par augmentation de l'assimilation d'aliments et réduction de la consommation lipidique. Il a été décrit que les taux de ghréline augmentent durant la phase pré-prandiale et diminuent juste après un repas, ceci suggérant qu'elle puisse jouer un rôle d'initiateur de la prise du repas. Cependant, la sécrétion de ghréline chez des sujets à jeun n'a pas encore été étudiée en détail. DESSIN: Les profils de sécrétion de ghréline pendant 24 heures ont été étudiés chez six sujets volontaires sains (3 femmes, 3 hommes; 25.5 ans; BMI 22.8 kg/m2) et comparés aux profils plasmatiques de l'hormone de croissance, de l'insuline et du glucose. METHODE: Des échantillons sanguins ont été prélevés toutes les 20 minutes pendant 24 heures et les taux de ghréline ont été mesurés par radio-immuno essai, utilisant un anticorps polyclonal de lapin. Le profil circadien de la sécrétion de ghréline (cluster analysis) a été évalué. RESULTATS: Une augmentation puis une diminution spontanée des taux de ghréline ont été observées aux moments où les sujets auraient habituellement mangé. La ghréline a été sécrétée de façon pulsatile avec approximativement 8 pics par 24 heures. Une diminution générale des taux de ghréline a également été observée durant la période d'étude. Aucune corrélation n'a pu être observée entre les taux de ghréline, d'homione de croissance, d'insuline et de glucose. CONCLUSIONS: Cette étude montre que pendant une période de jeûne les taux de ghréline suivent un profil similaire à ceux décrits chez des sujets mangeant 3 fois par jour. Durant le jeûne, l'hormone de croissance, l'insuline et le glucose ne semblent pas être impliqués dans la régulation de la sécrétion de ghréline. En outre, nous avons observé que la sécrétion de ghréline est pulsatile. La variation des taux de ghréline, indépendamment des repas, chez des sujets à jeun, renforce les observations préalables selon lesquelles le système nerveux central est primairement impliqué dans la régulation de la prise alimentaire. ABSTRACT: OBJECTIVE: Ghrelin stimulates GH release and causes weight gain through increased food intake and reduced fat utiIization. Ghrelin levels were shown to rise in the preprandial period and decrease shortly after meal consumption, suggesting a role as a possible meal initiator. However, ghrelin secretion in fasting subjects has not yet been studied in detail. DESIGN: 24-h ghrelin profiles were studied in six healthy volunteers (three females; 25.5 years; body mass index 22.8 kg/m2) and compared with GH, insulin and glucose levels. METHODS: Blood samples were taken every 20 min during a 24-h fasting period and total ghrelin levels were measured by RIA using a polyclonal rabbit antibody. The circadian pattern of ghrelin secretion and pulsatility (Cluster analysis) were evaluated. RESULTS: An increase and spontaneous decrease in ghrelin were seen at the timepoints of customary meals. Ghrelin was secreted in a pulsatile manner with approximately 8 peaks/24 h. An overall decrease in ghrelin levels was observed during the study period. There was no correlation of ghrelin with GH, insulin or blood glucose levels. CONCLUSIONS: This pilot study indicates that fasting ghrelin profiles display a circadian pattern similar to that described in people eating three times per day. In a fasting condition. GH, insulin and glucose do not appear to be involved in ghrelin regulation. In addition, we round that ghrelin is secreted in a pulsatile pattern. The variation in ghrelin independently of meals in fasting subjects supports previous observations that it is the brain that is primarily involved in the regulation of meal initiation.

The assessment of reproductive success of queens in ants and other social insects

Recently considerable research has focused on the causes of evolution of multiple-queen (polygynous) colonies. In order to better understand the factors which may have led to these polygynous associations it is vital to compare the reproductive success of queens in monogynous (one queen per colony) and polygynous colonies as well as the relative fitness of queens in polygynous colonies. This paper addresses the difficulties arising from such comparisons and their implications with regard to the methods commonly used to assess reproductive success in queens. The relative reproductive success of queens in monogynous and polygynous colonies is commonly assessed by comparing the relative number of reproductives they produce during a single reproductive season. However, shift in queen number seems to be only one aspect of a profound shift in social structure and reproductive strategy that constitutes, in effect, a ''polygyny syndrome''. For example, female reproductives produced in polygynous colonies frequently use a different mode of colony founding, which in turn affects the probability of their survival. Furthermore, queens from monogynous and polygynous colonies frequently differ in their life-span and the number of sexual broods they produce. As a result, the reproductive success of queens in monogynous and polygynous colonies may not be directly related to the relative number of sexuals they produce during a single reproductive season.

Neural substrates of social emotion regulation: a FMRI study on imitation and expressive suppression to dynamic facial signals.

Emotion regulation is crucial for successfully engaging in social interactions. Yet, little is known about the neural mechanisms controlling behavioral responses to emotional expressions perceived in the face of other people, which constitute a key element of interpersonal communication. Here, we investigated brain systems involved in social emotion perception and regulation, using functional magnetic resonance imaging (fMRI) in 20 healthy participants. The latter saw dynamic facial expressions of either happiness or sadness, and were asked to either imitate the expression or to suppress any expression on their own face (in addition to a gender judgment control task). fMRI results revealed higher activity in regions associated with emotion (e.g., the insula), motor function (e.g., motor cortex), and theory of mind (e.g., [pre]cuneus) during imitation. Activity in dorsal cingulate cortex was also increased during imitation, possibly reflecting greater action monitoring or conflict with own feeling states. In addition, premotor regions were more strongly activated during both imitation and suppression, suggesting a recruitment of motor control for both the production and inhibition of emotion expressions. Expressive suppression (eSUP) produced increases in dorsolateral and lateral prefrontal cortex typically related to cognitive control. These results suggest that voluntary imitation and eSUP modulate brain responses to emotional signals perceived from faces, by up- and down-regulating activity in distributed subcortical and cortical networks that are particularly involved in emotion, action monitoring, and cognitive control.

Gender-related psychological and behavioural correlates of pubertal timing in a national sample of Swiss adolescents.

The potential consequences of early and late puberty on the psychological and behavioural development of the adolescent are not well known. This paper presents focused analyses from the Swiss SMASH study, a self-administered questionnaire survey conducted among a representative sample of 7488 adolescents from 16 to 20 years old. Data from participants reporting early or late timing of puberty were compared with those reporting average timing of maturation. Early maturing girls reported a higher rate of dissatisfaction with body image (OR=1.32) and functional symptoms (OR=1.52) and reported engaging in sexual activity more often (OR=1.93). Early maturing boys reported engaging in exploratory behaviours (sexual intercourse, legal and illegal substance use) at a significantly higher rate (OR varying between 1.4 and 1.99). Both early and late maturing boys reported higher rates of dysfunctional eating patterns (OR=1.59 and 1.38, respectively), victimisation (OR=1.61 and 1.37, respectively) and depressive symptoms (OR=2.11 and 1.53, respectively). Clinicians should take into account the pubertal stage of their patients and provide them, as well as their parents, with appropriate counselling in the field of mental health and health behaviour.

Social inequalities of functioning and perceived health in Switzerland: a representative cross-sectional analysis.

Many people worldwide live with a disability, i.e. limitations in functioning. The prevalence is expected to increase due to demographic change and the growing importance of non-communicable disease and injury. To date, many epidemiological studies have used simple dichotomous measures of disability, even though the WHO's International Classification of Functioning, Disability, and Health (ICF) provides a multi-dimensional framework of functioning. We aimed to examine associations of socio-economic status (SES) and social integration in 3 core domains of functioning (impairment, pain, limitations in activity and participation) and perceived health. We conducted a secondary analysis of representative cross-sectional data of the Swiss Health Survey 2007 including 10,336 female and 8,424 male Swiss residents aged 15 or more. Guided by a theoretical ICF-based model, 4 mixed effects Poisson regressions were fitted in order to explain functioning and perceived health by indicators of SES and social integration. Analyses were stratified by age groups (15-30, 31-54, ≥55 years). In all age groups, SES and social integration were significantly associated with functional and perceived health. Among the functional domains, impairment and pain were closely related, and both were associated with limitations in activity and participation. SES, social integration and functioning were related to perceived health. We found pronounced social inequalities in functioning and perceived health, supporting our theoretical model. Social factors play a significant role in the experience of health, even in a wealthy country such as Switzerland. These findings await confirmation in other, particularly lower resourced settings.

Tapping the innovation potential of corporate engagement with stakeholders

Summary This dissertation explores how stakeholder dialogue influences corporate processes, and speculates about the potential of this phenomenon - particularly with actors, like non-governmental organizations (NGOs) and other representatives of civil society, which have received growing attention against a backdrop of increasing globalisation and which have often been cast in an adversarial light by firms - as a source of teaming and a spark for innovation in the firm. The study is set within the context of the introduction of genetically-modified organisms (GMOs) in Europe. Its significance lies in the fact that scientific developments and new technologies are being generated at an unprecedented rate in an era where civil society is becoming more informed, more reflexive, and more active in facilitating or blocking such new developments, which could have the potential to trigger widespread changes in economies, attitudes, and lifestyles, and address global problems like poverty, hunger, climate change, and environmental degradation. In the 1990s, companies using biotechnology to develop and offer novel products began to experience increasing pressure from civil society to disclose information about the risks associated with the use of biotechnology and GMOs, in particular. Although no harmful effects for humans or the environment have been factually demonstrated even to date (2008), this technology remains highly-contested and its introduction in Europe catalysed major companies to invest significant financial and human resources in stakeholder dialogue. A relatively new phenomenon at the time, with little theoretical backing, dialogue was seen to reflect a move towards greater engagement with stakeholders, commonly defined as those "individuals or groups with which. business interacts who have a 'stake', or vested interest in the firm" (Carroll, 1993:22) with whom firms are seen to be inextricably embedded (Andriof & Waddock, 2002). Regarding the organisation of this dissertation, Chapter 1 (Introduction) describes the context of the study, elaborates its significance for academics and business practitioners as an empirical work embedded in a sector at the heart of the debate on corporate social responsibility (CSR). Chapter 2 (Literature Review) traces the roots and evolution of CSR, drawing on Stakeholder Theory, Institutional Theory, Resource Dependence Theory, and Organisational Learning to establish what has already been developed in the literature regarding the stakeholder concept, motivations for engagement with stakeholders, the corporate response to external constituencies, and outcomes for the firm in terms of organisational learning and change. I used this review of the literature to guide my inquiry and to develop the key constructs through which I viewed the empirical data that was gathered. In this respect, concepts related to how the firm views itself (as a victim, follower, leader), how stakeholders are viewed (as a source of pressure and/or threat; as an asset: current and future), corporate responses (in the form of buffering, bridging, boundary redefinition), and types of organisational teaming (single-loop, double-loop, triple-loop) and change (first order, second order, third order) were particularly important in building the key constructs of the conceptual model that emerged from the analysis of the data. Chapter 3 (Methodology) describes the methodology that was used to conduct the study, affirms the appropriateness of the case study method in addressing the research question, and describes the procedures for collecting and analysing the data. Data collection took place in two phases -extending from August 1999 to October 2000, and from May to December 2001, which functioned as `snapshots' in time of the three companies under study. The data was systematically analysed and coded using ATLAS/ti, a qualitative data analysis tool, which enabled me to sort, organise, and reduce the data into a manageable form. Chapter 4 (Data Analysis) contains the three cases that were developed (anonymised as Pioneer, Helvetica, and Viking). Each case is presented in its entirety (constituting a `within case' analysis), followed by a 'cross-case' analysis, backed up by extensive verbatim evidence. Chapter 5 presents the research findings, outlines the study's limitations, describes managerial implications, and offers suggestions for where more research could elaborate the conceptual model developed through this study, as well as suggestions for additional research in areas where managerial implications were outlined. References and Appendices are included at the end. This dissertation results in the construction and description of a conceptual model, grounded in the empirical data and tied to existing literature, which portrays a set of elements and relationships deemed important for understanding the impact of stakeholder engagement for firms in terms of organisational learning and change. This model suggests that corporate perceptions about the nature of stakeholder influence the perceived value of stakeholder contributions. When stakeholders are primarily viewed as a source of pressure or threat, firms tend to adopt a reactive/defensive posture in an effort to manage stakeholders and protect the firm from sources of outside pressure -behaviour consistent with Resource Dependence Theory, which suggests that firms try to get control over extemal threats by focussing on the relevant stakeholders on whom they depend for critical resources, and try to reverse the control potentially exerted by extemal constituencies by trying to influence and manipulate these valuable stakeholders. In situations where stakeholders are viewed as a current strategic asset, firms tend to adopt a proactive/offensive posture in an effort to tap stakeholder contributions and connect the organisation to its environment - behaviour consistent with Institutional Theory, which suggests that firms try to ensure the continuing license to operate by internalising external expectations. In instances where stakeholders are viewed as a source of future value, firms tend to adopt an interactive/innovative posture in an effort to reduce or widen the embedded system and bring stakeholders into systems of innovation and feedback -behaviour consistent with the literature on Organisational Learning, which suggests that firms can learn how to optimize their performance as they develop systems and structures that are more adaptable and responsive to change The conceptual model moreover suggests that the perceived value of stakeholder contribution drives corporate aims for engagement, which can be usefully categorised as dialogue intentions spanning a continuum running from low-level to high-level to very-high level. This study suggests that activities aimed at disarming critical stakeholders (`manipulation') providing guidance and correcting misinformation (`education'), being transparent about corporate activities and policies (`information'), alleviating stakeholder concerns (`placation'), and accessing stakeholder opinion ('consultation') represent low-level dialogue intentions and are experienced by stakeholders as asymmetrical, persuasive, compliance-gaining activities that are not in line with `true' dialogue. This study also finds evidence that activities aimed at redistributing power ('partnership'), involving stakeholders in internal corporate processes (`participation'), and demonstrating corporate responsibility (`stewardship') reflect high-level dialogue intentions. This study additionally finds evidence that building and sustaining high-quality, trusted relationships which can meaningfully influence organisational policies incline a firm towards the type of interactive, proactive processes that underpin the development of sustainable corporate strategies. Dialogue intentions are related to type of corporate response: low-level intentions can lead to buffering strategies; high-level intentions can underpin bridging strategies; very high-level intentions can incline a firm towards boundary redefinition. The nature of corporate response (which encapsulates a firm's posture towards stakeholders, demonstrated by the level of dialogue intention and the firm's strategy for dealing with stakeholders) favours the type of learning and change experienced by the organisation. This study indicates that buffering strategies, where the firm attempts to protect itself against external influences and cant' out its existing strategy, typically lead to single-loop learning, whereby the firm teams how to perform better within its existing paradigm and at most, improves the performance of the established system - an outcome associated with first-order change. Bridging responses, where the firm adapts organisational activities to meet external expectations, typically leads a firm to acquire new behavioural capacities characteristic of double-loop learning, whereby insights and understanding are uncovered that are fundamentally different from existing knowledge and where stakeholders are brought into problem-solving conversations that enable them to influence corporate decision-making to address shortcomings in the system - an outcome associated with second-order change. Boundary redefinition suggests that the firm engages in triple-loop learning, where the firm changes relations with stakeholders in profound ways, considers problems from a whole-system perspective, examining the deep structures that sustain the system, producing innovation to address chronic problems and develop new opportunities - an outcome associated with third-order change. This study supports earlier theoretical and empirical studies {e.g. Weick's (1979, 1985) work on self-enactment; Maitlis & Lawrence's (2007) and Maitlis' (2005) work and Weick et al's (2005) work on sensegiving and sensemaking in organisations; Brickson's (2005, 2007) and Scott & Lane's (2000) work on organisational identity orientation}, which indicate that corporate self-perception is a key underlying factor driving the dynamics of organisational teaming and change. Such theorizing has important implications for managerial practice; namely, that a company which perceives itself as a 'victim' may be highly inclined to view stakeholders as a source of negative influence, and would therefore be potentially unable to benefit from the positive influence of engagement. Such a selfperception can blind the firm from seeing stakeholders in a more positive, contributing light, which suggests that such firms may not be inclined to embrace external sources of innovation and teaming, as they are focussed on protecting the firm against disturbing environmental influences (through buffering), and remain more likely to perform better within an existing paradigm (single-loop teaming). By contrast, a company that perceives itself as a 'leader' may be highly inclined to view stakeholders as a source of positive influence. On the downside, such a firm might have difficulty distinguishing when stakeholder contributions are less pertinent as it is deliberately more open to elements in operating environment (including stakeholders) as potential sources of learning and change, as the firm is oriented towards creating space for fundamental change (through boundary redefinition), opening issues to entirely new ways of thinking and addressing issues from whole-system perspective. A significant implication of this study is that potentially only those companies who see themselves as a leader are ultimately able to tap the innovation potential of stakeholder dialogue.

Long live the queen: studying aging in social insects

Aging is a fascinating, albeit controversial, chapter in biology. Few other subjects have elicited more than a century of ever-increasing scientific interest. In this review, we discuss studies on aging in social insects, a group of species that includes ants and termites, as well as certain bee and wasp species. One striking feature of social insects is the lifespan of queens (reproductive females), which can reach nearly 30 years in some ant species. This is over 100 times the average lifespan of solitary insects. Moreover, there is a tremendous variation in lifespan among castes, with queens living up to 500 times longer than males and 10 times longer than workers (non-reproductive individuals). This lifespan polymorphism has allowed researchers to test the evolutionary theory of aging and Y more recently Y to investigate the proximate causes of aging. The originality of these studies lies in their use of naturally evolved systems to address questions related to aging and lifespan determination that cannot be answered using the conventional model organisms.

Exercise efficiency relates with mitochondrial content and function in older adults.

Chronic aerobic exercise has been shown to increase exercise efficiency, thus allowing less energy expenditure for a similar amount of work. The extent to which skeletal muscle mitochondria play a role in this is not fully understood, particularly in an elderly population. The purpose of this study was to determine the relationship of exercise efficiency with mitochondrial content and function. We hypothesized that the greater the mitochondrial content and/or function, the greater would be the efficiencies. Thirty-eight sedentary (S, n = 23, 10F/13M) or athletic (A, n = 15, 6F/9M) older adults (66.8 ± 0.8 years) participated in this cross sectional study. V˙O2peak was measured with a cycle ergometer graded exercise protocol (GXT). Gross efficiency (GE, %) and net efficiency (NE, %) were estimated during a 1-h submaximal test (55% V˙O2peak). Delta efficiency (DE, %) was calculated from the GXT. Mitochondrial function was measured as ATPmax (mmol/L/s) during a PCr recovery protocol with (31)P-MR spectroscopy. Muscle biopsies were acquired for determination of mitochondrial volume density (MitoVd, %). Efficiencies were 17% (GE), 14% (NE), and 16% (DE) higher in A than S. MitoVD was 29% higher in A and ATPmax was 24% higher in A than in S. All efficiencies positively correlated with both ATPmax and MitoVd. Chronically trained older individuals had greater mitochondrial content and function, as well as greater exercise efficiencies. GE, NE, and DE were related to both mitochondrial content and function. This suggests a possible role of mitochondria in improving exercise efficiency in elderly athletic populations and allowing conservation of energy at moderate workloads.

Innovative implementation by non-state actors in environment-related areas : towards a positive implementation gap ?

This contribution (presented in the first International Conference on Public Policy (ICPP) in Grenoble in June 2013) explores the phenomena of innovation in action ("innovative implementation"). To do so, we operationalize "innovative implementation" as a strategy by which (coalitions of) non-state actors seek to develop ad hoc solutions to address a given environmental issue, going beyond what is provided for in formal policy designs. Following an inductive research strategy, we elaborate a conceptual framework whose main advantage is to bring the actors and their coalition (in all their diversity) back in the analysis. More concretely, we state that perceiving implementation as broader 'social interaction processes' (De Boer & Bressers 2011) within which actors play strategic 'games' (Bardach 1977, Scharpf 1997) opens interesting lines of research to better account for their innovative and strategic behaviours. In a second step, we apply this framework to three strategies of innovative implementation in different contexts, and identify on this basis empirical regularities in the individual pathways related to the emergence and success (or failure) of these strategies.

SocialPosition : Social Position Indicators Construction Toolbox

This R package provides to sociologists (and related scientists) a toolbox to facilitate the construction of social position indicators from survey data. Social position indicators refer to what is commonly known as social class and social status. There exists in the sociological literature many theoretical conceptualisation and empirical operationalization of social class and social status. This first version of the package offers tools to construct the International Socio-Economic Index of Occupational Status (ISEI) and the Oesch social class schema. It also provides tools to convert several occupational classifications (PCS82, PCS03, and ISCO08) into a common one (ISCO88) to facilitate data harmonisation work, and tools to collapse (i.e. group) modalities of social position indicators.

The vertical dimension of social relations and accurate interpersonal perception: A meta-analysis (Publishd online: 24 Oct. 2014)

There is little consensus regarding how verticality (social power, dominance, and status) is related to accurate interpersonal perception. The relation could be either positive or negative, and there could be many causal processes at play. The present article discusses the theoretical possibilities and presents a meta-analysis of this question. In studies using a standard test of interpersonal accuracy, higher socioeconomic status (SES) predicted higher accuracy defined as accurate inference about the meanings of cues; also, higher experimentally manipulated vertical position predicted higher accuracy defined as accurate recall of others' words. In addition, although personality dominance did not predict accurate inference overall, the type of personality dominance did, such that empathic/responsible dominance had a positive relation and egoistic/aggressive dominance had a negative relation to accuracy. In studies involving live interaction, higher experimentally manipulated vertical position produced lower accuracy defined as accurate inference about cues; however, methodological problems place this result in doubt.

Effects of Three Types of Exercise Interventions on Healthy Old Adults' Gait Speed : A Systematic Review and Meta-Analysis.

BACKGROUND: Habitual walking speed predicts many clinical conditions later in life, but it declines with age. However, which particular exercise intervention can minimize the age-related gait speed loss is unclear. PURPOSE: Our objective was to determine the effects of strength, power, coordination, and multimodal exercise training on healthy old adults' habitual and fast gait speed. METHODS: We performed a computerized systematic literature search in PubMed and Web of Knowledge from January 1984 up to December 2014. Search terms included 'Resistance training', 'power training', 'coordination training', 'multimodal training', and 'gait speed (outcome term). Inclusion criteria were articles available in full text, publication period over past 30 years, human species, journal articles, clinical trials, randomized controlled trials, English as publication language, and subject age ≥65 years. The methodological quality of all eligible intervention studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. We computed weighted average standardized mean differences of the intervention-induced adaptations in gait speed using a random-effects model and tested for overall and individual intervention effects relative to no-exercise controls. RESULTS: A total of 42 studies (mean PEDro score of 5.0 ± 1.2) were included in the analyses (2495 healthy old adults; age 74.2 years [64.4-82.7]; body mass 69.9 ± 4.9 kg, height 1.64 ± 0.05 m, body mass index 26.4 ± 1.9 kg/m(2), and gait speed 1.22 ± 0.18 m/s). The search identified only one power training study, therefore the subsequent analyses focused only on the effects of resistance, coordination, and multimodal training on gait speed. The three types of intervention improved gait speed in the three experimental groups combined (n = 1297) by 0.10 m/s (±0.12) or 8.4 % (±9.7), with a large effect size (ES) of 0.84. Resistance (24 studies; n = 613; 0.11 m/s; 9.3 %; ES: 0.84), coordination (eight studies, n = 198; 0.09 m/s; 7.6 %; ES: 0.76), and multimodal training (19 studies; n = 486; 0.09 m/s; 8.4 %, ES: 0.86) increased gait speed statistically and similarly. CONCLUSIONS: Commonly used exercise interventions can functionally and clinically increase habitual and fast gait speed and help slow the loss of gait speed or delay its onset.

Regional differences of physical activity and sedentary behaviour in Swiss children are not explained by socio-demographics or the built environment.

OBJECTIVE: We evaluated whether regional differences in physical activity (PA) and sedentary behaviour (SB) existed along language boundaries within Switzerland and whether potential differences would be explained by socio-demographics or environmental characteristics. METHODS: We combined data of 611 children aged 4 to 7 years from four regional studies. PA and SB were assessed by accelerometers. Information about the socio-demographic background was obtained by questionnaires. Objective neighbourhood attributes could be linked to home addresses. Multivariate regression models were used to test associations between PA and SB and socio-demographic characteristics and neighbourhood attributes. RESULTS: Children from the German compared to the French-speaking region were more physically active and less sedentary (by 10-15 %, p < 0.01). Although German-speaking children lived in a more favourable environment and a higher socioeconomic neighbourhood (differences p < 0.001), these characteristics did not explain the differences in PA behaviour between French and German speaking. CONCLUSIONS: Factors related to the language region, which might be culturally rooted were among the strongest correlates of PA and SB among Swiss children, independent of individual, social and environmental factors.