Experimentally increased group diversity improves disease resistance in an ant species.

A leading hypothesis linking parasites to social evolution is that more genetically diverse social groups better resist parasites. Moreover, group diversity can encompass factors other than genetic variation that may also influence disease resistance. Here, we tested whether group diversity improved disease resistance in an ant species with natural variation in colony queen number. We formed experimental groups of workers and challenged them with the fungal parasite Metarhizium anisopliae. Workers originating from monogynous colonies (headed by a single queen and with low genetic diversity) had higher survival than workers originating from polygynous ones, both in uninfected groups and in groups challenged with M. anisopliae. However, an experimental increase of group diversity by mixing workers originating from monogynous colonies strongly increased the survival of workers challenged with M. anisopliae, whereas it tended to decrease their survival in absence of infection. This experiment suggests that group diversity, be it genetic or environmental, improves the mean resistance of group members to the fungal infection, probably through the sharing of physiological or behavioural defences.

Nation-wide survey on radiation doses in diagnostic and interventional radiology in Switzerland in 1998.

A nation-wide survey on radiation doses in diagnostic and interventional radiology was conducted in Switzerland in 1998 aiming at establishing their collective radiological impact on the Swiss population. The study consisted on the one hand of surveying the frequency of more than 250 types of examinations, covering conventional radiology, mammography, fluoroscopy, angiography, interventional radiology, CT, bone densitometry, conventional tomography and dental radiology. On the other hand, for each type of examination the associated patient dose was established by modeling. The results of this study show that about 9.5 million diagnostic and interventional examinations are performed annually in Switzerland (1.34 per caput) and that the associated annual collective dose is of the order of 7100 person.Sv (1.0 mSv per caput). Switzerland is similar to other European countries in terms of the frequency of examinations and the collective dose.

Contribution to the conservation biology of the wood ant Formica lugubris (Hymenoptera, Formicidae) in Switzerland

Summary Among ants, wood ants are probably the most fascinating and studied species in temperate European forests. Unfortunately, due to several threats they are nowadays registered in red lists. Recent studies made in the Swiss Jura Mountains ended up in the description of a new sympatric sibling species of Formica lugubris (i.e. Formica paralugubris Seifert 1996). Because of this confusion the biology of F. lugubris is incomplete. Due to the extreme difficulties to distinguish morphologically F. lugubris from F. paralugubris we studied their cuticular hydrocarbons profiles. Irrespective of their geographic origin, we observed quantitative discrimination between species within each caste (workers, males and gynes =young alate female). Moreover, using a behavioural taxonomic approach (i.e. the pupa-carrying test) we showed that ants preferred conspecific worker pupae to those of the sibling species. These first results allowed us to consider the two species as two separate taxonomic units. To understand their coexistence, habitat distribution models were fitted with GIS predictors and factors known to influence wood ant distribution. In the Jura Mountains, although the two species share very similar habitats, they are spatially segregated. F. lugubris occurs more frequently at woodland borders than in forest interiors. We demonstrated with genetic and field data that Formica lugubris displays two different social forms in close proximity in alpine zone (e.g. unmanaged forests of the Swiss National Park). We discovered populations mostly monogynous to weakly polygynous (i.e. one to a few egg laying queens per colony) and monodomous (i.e. one nest per colony), and polygynous/polydomous populations (new nests being founded by colony budding). It is generally admitted that monogyne species disperse well in order to find suitable habitat to found new colonies whereas polygyne species have restricted dispersal and local mating within the nest. In order to compare reproductive strategies of F. lugubris and F. paralugubris (i.e. matings and dealation process) we conducted experiments with sexuals. F, lugubris gynes from monogynous/monodomous populations do not show a local strategy like the obligately polygynous F. paralugubris (i.e. early dealation even without mating, insemination without flight activity and low fat reserve). They always keep their wings, do not mate when not able to fly and have high amount of fat content revealing high survival capacities. On the other side, F, lugubris gynes from polygynous/polydomous populations have lower lipid reserves and displayed a reproductive behaviour close to the F. para lugubris one. After dispersal, wood ant gynes can either start new societies by temporary social parasitism of another species (i.e. subgenus Serviformica) or be adopted intraspecifically in an existing nest. In F. lugubris, we demonstrated that gynes from monogynous/monodomous colonies showed a high success for temporary social parasitism compare to the lower success of gynes from polygynous/polydomous colonies. However, physiological analyses suggested that only gynes from monogynous/ monodomous populations can efficiently disperse and found new nest by temporary social parasitism. Intraspecifically, gynes were accepted to a high degree in polygynous nest and in monogynous nests as long as these nests contained sexuals. In conclusion, Formica lugubris displays a social and dispersal polymorphism (mixed mating and founding system) representing a behavioural plasticity in relation to environmental and ecological conditions. Therefore, conservation measures directed toward this species should try to maintain a maximum of diversity at the habitat level. Résumé Les fourmis des bois sont probablement parmi les espèces de fourmis les plus fascinantes et les plus étudiées des forêts tempérées Européennes. Actuellement, du fait de différentes menaces, elles figurent malheureusement sur listes rouges. Plusieurs études menées au sein du Jura Suisse ont abouti à la description d'une nouvelle espèce jumelle et sympatrique de Formica lugubris (F. para- lugubris Seifert 1996). A cause de cette confusion la biologie de F lugubris est lacunaire. La distinction morphologique de F. lugubris et de F. para lugubris est si difficile que nous avons étudié leurs hydrocarbures cuticulaires. Indépendamment de l'origine géographique, nous avons observé une discrimination quantitative entre les espèces au sein de chaque caste (ouvrières, mâles et jeunes femelles ailées). De plus, à l'aide d'une approche taxonomique comportementale (le test de transport de cocons) nous avons montré que les fourmis préfèrent des cocons d'ouvrières conspécifiques à ceux de l'espèce jumelle. Ces premiers résultats nous permettent de considérer ces deux espèces comme deux unités taxonomiques distinctes et valables. Afin de comprendre leur coexistence, des modèles mathématiques ont été développés avec des données SIG et des facteurs écologiques influençant la répartition des fournis des bois. Dans le Jura, même si elles partagent des habitats fortement similaires, les deux espèces n'occupent pas les mêmes secteurs. F. lugubris est plus fréquente en lisière forestière plutôt qu'en pleine forêt. Nous avons démontré grâce à des données génétiques et de terrain que F. lugubris présente deux formes sociales au sein de la zone alpine (forêts protégées du Parc National Suisse). D'autre part, nous avons découvert des populations monogynes à faiblement polygynes (une à quelques reines pondeuses par colonie) et monodomes (colonies composées d'une seule fourmilière), et des populations polygynes/polydomes (les nouveaux nids étant produit par bourgeonnement). Généralement, les espèces monogynes dispersent sur de grandes distances et peuvent coloniser des habitats favorables à la fondation de nouvelles colonies alors que les espèces polygynes possèdent une dispersion limitée avec des accouplements à l'intérieur des nids. Afin de comparer les stratégies de reproduction de F. lugubris et de F. paralugubris (accouplements et perte des ailes) nous avons mené des expériences avec les sexués. Les jeunes femelles ailées de F. lugubris issues de populations monogynes/monodomes ne présentent pas de stratégie locale comparée à l'espèce obligatoirement polygyne F paralugubris (perte des ailes précoce même si il n'y a pas eu accouplement, insémination possible sans avoir volé activement et faibles réserves de graisse). Elles conservent toujours leurs ailes, ne s'accouplent pas lorsqu'elles sont empêchées de voler et possèdent de grandes quantités de graisse révélant de fortes capacités de survie. D'autre part, les jeunes femelles ailées de F. lugubris provenant de populations polygynes/polydomes ont peu de réserves lipidiques et ont un comportement de reproduction proche de celles de F. paralugubris. Après leur dispersion, les jeunes sexués femelles de fourmis des bois peuvent soit fonder une nouvelle société par parasitisme social temporaire d'un nid d'une autre espèce (sous-genre Serviformica) soit être adoptées dans un nid déjà existant de leur propre espèce. Chez F. lugubris, nous avons pu démontrer que les jeunes sexués femelles de colonies monogynes/monodomes présentent un succès élevé au parasitisme sociale temporaire en comparaison au plus faible succès obtenu avec des sexués provenant de colonies polygynes/polydomes. Cependant, les données physiologiques suggèrent que seules les jeunes sexués femelles de populations mono-gynes/monodomes peuvent disperser efficacement et fonder un nouveau nid par parasitisme social temporaire. Au niveau intraspécifique, les jeunes femelles sont acceptées à un taux élevé dans les nids polygynes mais aussi dans les nids monogynes tant que ces nids possèdent encore de jeunes sexués. En conclusion, F. lugubris est caractérisée par un polymorphisme dans ses structures sociales et ses stratégies de dispersion (système mixte d'accouplement et de fondation) ce qui représente une forte plasticité comportementale en relation avec les conditions environnementales et écologiques. Par conséquent, les mesures de conservation de cette espèce devraient s'attacher à maintenir un maximum de diversité au niveau des habitats.

Association of working conditions with self-reported work-related symptoms: results from the Swiss dataset of the European Working Conditions Survey

Working conditions are important determinants of health. The aims of this article are to 1) identify working conditions and work characteristics that are associated with workers' perceptions that their work is harmful to their health and 2) identify with what symptoms these working conditions are associated.We used the Swiss dataset from the 2005 edition of the European Working Conditions Survey. The dependent variable was based on the question "Does your work affect your health?". Logistic regression was used to identify a set of variables collectively associated with self-reported work-related adverse health effects.A total of 330 (32%) participants reported having their health affected by work. The most frequent symptoms included backache (17.1%), muscular pains (13.1%), stress (18.3%) and overall fatigue (11.7%). Scores for self-reported exposure to physicochemical risks, postural and physical risks, high work demand, and low social support were all significantly associated with workers' perceptions that their work is harmful to their health, regardless of gender or age. A high level of education was associated with stress symptoms, and reports that health was affected by work was associated with low job satisfaction.Many workers believe that their work affects their health. Health specialists should pay attention to the potential association between work and their patients' health complaints. This is particularly relevant when patients mention symptoms such as muscular pains, backache, overall fatigue, and stress. Specific attention should be given to complaints of stress in highly educated workers.

Survey of Users of the USGS Stream-Gaging Network in Iowa, 1996, HR-383, 1996

A survey was sent to over 200 Federal, State, and local agencies that might use streamflow data collected by the U. S. Geological Survey in Iowa. A total of 181 forms were returned and 112 agencies indicated that they use streamflow data. The responses show that streamflow data from the Iowa USGS stream-gaging network, which in 1996 is composed of 117 stations, are used by many agencies for many purposes and that many stations provide streamflow data that fulfill a variety of joint purposes. The median number of respondents per station that use data from the station was 6 and the median number of data-use categories indicated per station was 9. The survey results can be used by agencies that fund the Iowa USGS stream-gaging network to help them decide which stations to continue to support if it becomes necessary to reduce the size of the stream-gaging network.

The determinants of queen size in a socially polymorphic ant.

In social animals, body size can be shaped by multiple factors, such as direct genetic effects, maternal effects, or the social environment. In ants, the body size of queens correlates with the social structure of the colony: colonies headed by a single queen (monogyne) generally produce larger queens that are able to found colonies independently, whereas colonies headed by multiple queens (polygyne) tend to produce smaller queens that stay in their natal colony or disperse with workers. We performed a cross-fostering experiment to investigate the proximate causes of queen size variation in the socially polymorphic ant Formica selysi. As expected if genetic or maternal effects influence queen size, eggs originating from monogyne colonies developed into larger queens than eggs collected from polygyne colonies, be they raised by monogyne or polygyne workers. In contrast, eggs sampled in monogyne colonies were smaller than eggs sampled in polygyne colonies. Hence, eggs from monogyne colonies are smaller but develop into larger queens than eggs from polygyne colonies, independently of the social structure of the workers caring for the brood. These results demonstrate that a genetic polymorphism or maternal effect transmitted to the eggs influences queen size, which probably affects the social structure of new colonies.

Efficacy and Safety of Certolizumab Pegol in an Unselected Crohn's Disease Population: 26 Week Data of the FACTS II Survey.

BACKGROUND: Certolizumab pegol (Cimzia, CZP) was approved for the treatment of Crohn's disease (CD) patients in 2007 in Switzerland as first country worldwide. This prospective phase IV study aimed to evaluate the efficacy and safety of CZP over 26 weeks in a multicenter cohort of practice-based patients. METHODS: Evaluation questionnaires at baseline, week 6 and 26 were completed by gastroenterologists in hospitals and private practices. RESULTS: Sixty patients (38F/22M) were included, 53% had complicated disease (stricturing or penetrating), 45% had undergone prior CD related surgery. All patients had prior exposure to systemic steroids, 96% to immunomodulators, 73% to infliximab, and 43% to adalimumab. A significant decrease of Harvey Bradshaw Index (HBI) was observed under CZP therapy (12.24.9 at week 0 vs 6.34.7 at week 6 and 6.75.3 at week 26, both P <0.001). Response and remission rates were 70% and 40% (week 6) and 67% and 36% respectively (week 26). The complete perianal fistula closure rate was 36% at week 6 and 55% at week 26. The frequency of adverse drug reactions attributed to CZP was 5%. CZP was continued in 88% of patients beyond week 6 and in 67% beyond week 26. CONCLUSIONS: In a population of CD patients with predominantly complicated disease behaviour, CZP proved to be effective in induction and maintenance of response and remission. This series provides the first evidence of CZP's effectiveness in perianal fistulizing CD in clinical practice.

Validation of the 34-item Supportive Care Needs Survey and 8-item Breast module French versions (SCNS-SF34-Fr and SCNS-BR8-Fr) in breast cancer patients.

This study aimed to assess the psychometric robustness of the French version of the Supportive Care Needs Survey and breast cancer (BC) module (SCNS-SF34-Fr and SCNS-BR8-Fr). Breast cancer patients were recruited in two hospitals (in Paris, France and Lausanne, Switzerland) either in ambulatory chemotherapy or radiotherapy, or surgery services. They were invited to complete the SCNS-SF34-Fr and SCNS-BR8-Fr as well as quality of life and patient satisfaction questionnaires. Three hundred and eighty-four (73% response rate) BC patients returned completed questionnaires. A five-factor model was confirmed for the SCNS-SF34-Fr with adequate goodness-of-fit indexes, although some items evidenced content redundancy, and a one-factor was identified for the SCNS-BR8-Fr. Internal consistency and test-retest estimates were satisfactory for most scales. The SCNS-SF34-Fr and SCNS-BR8-Fr scales demonstrated conceptual differences with the quality of life and satisfaction with care scales, highlighting the specific relevance of this assessment. Different levels of needs could be differentiated between groups of BC patients in terms of age and level of education (P < 0.001). The SCNS-SF34-Fr and SCNS-BR8-Fr present adequate psychometric properties despite some redundant items. These questionnaires allow for the crucial endeavour to design appropriate care services according to BC patients' characteristics.

A productivity map of cognitive pretest methos for improving survey questions

Interest in cognitive pretest methods for evaluating survey questionnaires has been increasing for the last three decades. However, analysing the features of the scientific output in the field can be difficult due to its prevalence in public and private institutes whose main mission is not scientific research. The aim of this research is to characterize the current state of scientific output in the field by means of two bibliometric studies for the period from 1980 to 2007. Study 1 analysed documents obtained from the more commonly used bibliographic databases. Study 2 supplemented the body of documents from Study 1 with documents from non-indexed journals, conference papers, etc. Results show a constant growth in the number of publications. The wide dispersion of publication sources, together with the highlighted role of the public and private institutions as centres of production, can also be identified as relevant characteristics of the scientific output in this field.