Two's company, three's a crowd: experimental evaluation of the evolutionary maintenance of trioecy in Mercurialis annua (Euphorbiaceae).

Trioecy is an uncommon sexual system in which males, females, and hermaphrodites co-occur as three clearly different gender classes. The evolutionary stability of trioecy is unclear, but would depend on factors such as hermaphroditic sex allocation and rates of outcrossing vs. selfing. Here, trioecious populations of Mercurialis annua are described for the first time. We examined the frequencies of females, males and hermaphrodites across ten natural populations and evaluated the association between the frequency of females and plant densities. Previous studies have shown that selfing rates in this species are density-dependent and are reduced in the presence of males, which produce substantially more pollen than hermaphrodites. Accordingly, we examined the evolutionary stability of trioecy using an experiment in which we (a) indirectly manipulated selfing rates by altering plant densities and the frequency of males in a fully factorial manner across 20 experimental plots and (b) examined the effect of these manipulations on the frequency of the three sex phenotypes in the next generation of plants. In the parental generation, we measured the seed and pollen allocations of hermaphrodites and compared them with allocations by unisexual plants. In natural populations, females occurred at higher frequencies in denser patches, a finding consistent with our expectations. Under our experimental conditions, however, no combination of plant densities and male frequencies was associated with increased frequencies of females. Our results suggest that the factors that regulate female frequencies in trioecious populations of M. annua are independent of those regulating male frequencies (density), and that the stable co-existence of all three sex phenotypes within populations is unlikely.

Self-reported health needs and use of primary health care services by adolescents enrolled in post-mandatory schools or vocational training programmes in Switzerland.

BACKGROUND: The second Swiss Multicenter Adolescent Survey on Health (SMASH02) was conducted among a representative sample (n = 7428) of students and apprentices aged 16 to 20 from the three language areas of Switzerland during the year 2002. This paper reports on health needs expressed by adolescents and their use of health care services over the 12 months preceding the survey. METHODS: Nineteen cantons representing 80% of the resident population agreed to participate. A complex iterative random cluster sample of 600 classes was drawn with classes as primary sampling unit. The participation rate was 97.7% for the classes and 99.8% for the youths in attendance. The self-administered questionnaire included 565 items. The median rate of item non-response was 1.8%. Ethical and legal requirements applying to surveys of adolescent populations were respected. RESULTS: Overall more than 90% of adolescents felt in good to excellent health. Suffering often or very often from different physical complaints or pain was also reported such as headache (boys: 15.9%, girls: 37.4%), stomach-ache (boys: 9.7%, girls: 30.0%), joint pain (boys: 24.7%, girls: 29.5%) or back pain (boys: 24.3%, girls: 34.7%). Many adolescents reported a need for help on psychosocial and lifestyle issues, such as stress (boys: 28.5%, girls: 47.7%) or depression (boys: 18.9%, girls: 34.4%). Although about 75% of adolescents reported having consulted a general practitioner and about one-third having seen another specialist, reported reasons for visits do not correspond to the expressed needs. Less than 10% of adolescents had visited a psychiatrist, a family planning centre or a social worker. CONCLUSIONS: The reported rates of health services utilisation by adolescents does not match the substantial reported needs for help in various areas. This may indicate that the corresponding problems are not adequately detected and/or addressed by professionals from the health and social sectors.

Determinants of school efficiency : The case of primary schools in the State of Geneva, Switzerland

The public primary school system in the State of Geneva, Switzerland, is characterized by centrally evaluated pupil performance measured with the use of standardized tests. As a result, consistent data are collected among the system. The 2010-2011 dataset is used to develop a two-stage data envelopment analysis (DEA) of school efficiency. In the first stage, DEA is employed to calculate an individual efficiency score for each school. It shows that, on average, each school could reduce its inputs by 7% whilst maintaining the same quality of pupil performance. The cause of inefficiency lies in perfectible management. In the second stage, efficiency is regressed on school characteristics and environmental variables;external factors outside of the control of headteachers. The model is tested for multicollinearity, heteroskedasticity and endogeneity. Four variables are identified as statistically significant. School efficiency is negatively influenced by (1) the provision of special education, (2) the proportion of disadvantaged pupils enrolled at the school and (3) operations being held on multiple sites, but positively influenced by school size (captured by the number of pupils). The proportion of allophone pupils; schools located in urban areas and the provision of reception classes for immigrant pupils are not significant. Although the significant variables influencing school efficiency are outside of the control of headteachers, it is still possible to either boost the positive impact or curb the negative impact. Dans le canton de Genève (Suisse), les écoles publiques primaires sont caractérisées par un financement assuré par les collectivités publiques (canton et communes) et par une évaluation des élèves à l'aide d'épreuves standardisées à trois moments distincts de leur scolarité. Cela permet de réunir des informations statistiques consistantes. La base de données de l'année 2010-2011 est utilisée dans une analyse en deux étapes de l'efficience des écoles. Dans une première étape, la méthode d'analyse des données par enveloppement (DEA) est utilisée pour calculer un score d'efficience pour chaque école. Cette analyse démontre que l'efficience moyenne des écoles s'élève à 93%. Chaque école pourrait, en moyenne, réduire ses ressources de 7% tout en conservant constants les résultats des élèves aux épreuves standardisées. La source de l'inefficience réside dans un management des écoles perfectible. Dans une seconde étape, les scores d'efficience sont régressés sur les caractéristiques des écoles et sur des variables environnementales. Ces variables ne sont pas sous le contrôle (ou l'influence) des directeurs d'école. Le modèle est testé pour la multicolinéartié, l'hétéroscédasticité et l'endogénéité. Quatre variables sont statistiquement significatives. L'efficience des écoles est influencée négativement par (1) le fait d'offrir un enseignement spécialisé en classe séparée, (2) la proporition d'élèves défavorisés et (3) le fait d'opérer sur plusieurs sites différents. L'efficience des écoles est influencée positivement par la taille de l'école, mesurée par le nombre d'élèves. La proporition d'élèves allophones, le fait d'être situé dans une zone urbaine et d'offrir des classes d'accueil pour les élèves immigrants constituent autant de variables non significatives. Le fait que les variables qui influencent l'efficience des écoles ne soient pas sous le contrôle des directeurs ne signifie pas qu'il faille céder au fatalisme. Différentes pistes sont proposées pour permettre soit de réduire l'impact négatif soit de tirer parti de l'impact positif des variables significatives.

The Swiss Business Elite (1980-2000): How the Changing Composition of the Elite Explains the Decline of the Swiss Company Network

In this paper we analyse the decline of the Swiss corporate network between 1980 and 2000. We address the theoretical and methodological challenge of this transformation by the use of a combination of network analysis and multiple correspondence analysis (MCA). Based on a sample of top managers of the 110 largest Swiss companies in 1980 and 2000 we show that, beyond an adjustment to structural pressure, an explanation of the decline of the network has to include the strategies of the fractions of the business elites. We reveal that three factors contribute crucially to the decline of the Swiss corporate network: the managerialization of industrial leaders, the marginalization of law degree holders and the influx of hardly connected foreign managers.

Addressing elementary school teachers' professional stressors: Practical suggestions for schools and adminstrators

Purpose: Given the preponderance of education reform since the No Child Left Behind Act (U.S. Department of Education, 2001), reform efforts have shaped the nature of the work and culture in schools. The emphasis on standardized testing to determine schools' status and student performance, among other factors, has generated stress, particularly for teachers. Therefore, district and school administrators are encouraged to consider the contextual factors that contribute to teacher stress to address them and to retain high-performing teachers. Research Methods/Approach: Participants were recruited from two types of schools in order to test hypotheses related to directional responding as a function of working in a more challenging (high-priority) or less challenging (non-high-priority) school environment. We employed content analysis to analyze 64 suburban elementary school teachers' free-responses to a prompt regarding their stress as teachers. We cross-analyzed our findings through external auditing to bolster trustworthiness in the data and in the procedure. Findings: Teachers reported personal and contextual stressors. Herein, we reported concrete examples of the five categories of contextual stressors teachers identified: political and educational structures, instructional factors, student factors, parent and family factors, and school climate. We found directional qualities and overlapping relationships in the data, partially confirming our hypotheses. Implications for Research and Practice: We offer specific recommendations for practical ways in which school administrators might systemically address teacher stress based on the five categories of stressors reported by participants. We also suggest means of conducting action research to measure the effects of implemented suggestions.

The future of leadership

The good news with regard to this (or any) chapter on the future of leadership is that there is one. There was a time when researchers called for a moratorium on new leadership theory and research (e.g., Miner, 1975) citing the uncertain future of the field. Then for a time there was a popular academic perspective that leadership did not really matter when it came to shaping organizational outcomes (Meindl & Ehrlich, 1987; Meindl, Ehrlich, & Dukerich, 1985; Pfeffer, 1977). That perspective was laid to rest by "realists" in the field (Day & Antonakis, 2012a) by means of empirical re-interpretation of the results used to support the position that leadership does not matter (Lieberson & O'Connor, 1972; Salancik & Pfeffer, 1977). Specifically, Day and Lord (1988) showed that when proper methodological concerns were addressed (e.g., controlling for industry and company size effects; incorporating appropriate time lags) that the impact of top-level leadership was considerable - explaining as much as 45% of the variance in measures of organizational performance. Despite some recent pessimistic sentiments about the "curiously unformed" state of leadership research and theory (Hackman & Wageman, 2007), others have argued that the field has continued to evolve and is potentially on the threshold of some significant breakthroughs (Day & Antonakis, 2012a). Leadership scholars have been re-energized by new directions in the field and research efforts have revitalized areas previously abandoned for apparent lack of consistency in findings (e.g., leadership trait theory). Our accumulated knowledge now allows us to explain the nature of leadership including its biological bases and other antecedents, and consequences with some degree of confidence. There are other comprehensive sources that review the extensive theoretical and empirical foundation of leadership (Bass, 2008; Day & Antonakis, 2012b) so that will not be the focus of the present chapter. Instead, we will take a future-oriented perspective in identifying particular areas within the leadership field that we believe offer promising perspectives on the future of leadership. Nonetheless, it is worthwhile as background to first provide an overview of how we see the leadership field changing over the past decade or so. This short chronicle will set the stage for a keener understanding of where the future contributions are likely to emerge. Overall, across nine major schools of leadership - trait, behavioural, contingency, contextual, relational, sceptics, information processing, New Leadership, biological and evolutionary - researchers have seen a resurgence in interest in one area, a high level of activity in at least four other areas, inactivity in three areas, and one that was modestly active in the previous decade but we think holds strong promise for the future (Gardner, Lowe, Moss, Mahoney, & Cogliser, 2010). We will next provide brief overviews of these nine schools and their respective levels of research activity (see Figure 1).

Prevalence and determinants of obesity in children in public schools of Sintra, Portugal

OBJECTIVE: To assess the prevalence of and the factors related to overweight and obesity in a sample of children from the region of Sintra, Portugal. METHODS AND PROCEDURES: Cross-sectional study, stratified for freguesia with random selection of schools. Height, weight, triceps skinfold, upper arm and waist circumferences were measured, and overweight/obesity defined according to international criteria. Breast-feeding, number of daily meals and parents' height and weight data were also collected. RESULTS: One thousand two hundred and twenty-five children aged 6-10 years were assessed. Overall prevalence of overweight and obesity was 35.6% (23% overweight and 12.6% obesity). Overweight or obese children had higher triceps skinfold, upper arm circumference, arm muscle area, and waist circumference than their normal weight counterparts (P < 0.001). On multivariate analysis, relatively to a child without obese progenitors, a child with one obese progenitor had an obesity risk multiplied by 2.78 (95% confidence interval (CI): 1.76-4.38), while a child with two obese progenitors had a risk multiplied by 6.47 (95% CI: 5.59-16.19). Conversely, being picky was significantly related with a smaller risk of obesity: for boys, odds ratio (OR) = 0.15 (95% CI: 0.04-0.63); for girls, OR = 0.19 (95% CI: 0.06-0.64). Finally, no relationships were found between obesity, birth weight, birth height or breast-feeding. DISCUSSION: Prevalence of overweight and obesity are elevated among children of the Sintra region in Portugal compared to most other regions of Europe. The relationship with the parents' nutritional state stresses the need to target families for preventing obesity.