Linear relations between writhe and minimal crossing number in Conway families of ideal knots and links

We showed earlier how to predict the writhe of any rational knot or link in its ideal geometric configuration, or equivalently the average of the 3D writhe over statistical ensembles of random configurations of a given knot or link (Cerf and Stasiak 2000 Proc. Natl Acad. Sci. USA 97 3795). There is no general relation between the minimal crossing number of a knot and the writhe of its ideal geometric configuration. However, within individual families of knots linear relations between minimal crossing number and writhe were observed (Katritch et al 1996 Nature 384 142). Here we present a method that allows us to express the writhe as a linear function of the minimal crossing number within Conway families of knots and links in their ideal configuration. The slope of the lines and the shift between any two lines with the same

Trends in the association between height and socioeconomic indicators in France, 1970-2003

Average physical stature has increased dramatically during the 20th century in many populations across the world with few exceptions. It remains unclear if social inequalities in height persist despite improvements in living standards in the welfare economies of Western Europe. We examined trends in the association between height and socioeconomic indicators in adults over three decades in France. The data were drawn from the French Decennial Health Surveys: a multistage, stratified, random survey of households, representative of the population, conducted in 1970, 1980, 1991, and 2003. We categorised age into 10-year bands, 25-34, 35-44, 45-54 and 55-64 years. Education and income were the two socioeconomic measures used. The slope index of inequality (SII) was used as a summary index of absolute social inequalities in height. The results show that average height increased over this period; men and women aged 25-34 years were 171.9 and 161.2 cm tall in 1970 and 177.0 and 164.0 cm in 2003, respectively. However, education-related inequalities in height remained unchanged over this period and in men were 4.48 cm (1970), 4.71 cm (1980), 5.58 cm (1991) and 4.69 cm (2003), the corresponding figures in women were 2.41, 2.37, 3.14 and 2.96 cm. Income-related inequalities in height were smaller and much attenuated after adjustment for education. These results suggest that in France, social inequalities in adult height in absolute terms have remained unchanged across the three decades under examination.

Communication with terminal cancer patients in palliative care: are there differences between nurses and physicians?

The aim of this study was to find whether there were interprofessional differences in specific elements of communication with terminal cancer patients and decision-making processes that concern such patients. Given that interdisciplinary team work is one of the basic values in palliative care, if there are conflicting views between professions on such important issues it is most important to know about these and to understand them. A questionnaire utilized in an earlier survey of palliative care physicians and addressing their attitudes to and beliefs about specific elements of communication and decision making was sent to a sample of palliative care nurses working in the same regions, i.e. the French-speaking parts of Switzerland, Belgium and France. After a second mailing (reminder), 135 of the 163 questionnaires (83%) were returned. There was general agreement between nurses and physicians on questions dealing with perceptions of patients' knowledge of their diagnosis and stage of disease, patients' need for information, "do not resuscitate" orders and ethical principles in decision-making processes. Statistically significant, but small, differences between professional groups were only observed for a minority of the questions. Interprofessional differences in specific elements of communication with terminal cancer patients and decision-making processes affecting these patients were not so marked that they could be called "conflicting interprofessional views."

Structural, metamorphic and geochronological relations between the Zanskar Shear Zone and the Miyar Shear Zone (NW Indian Himalaya): Evidence for two distinct tectonic structures and implications for the evolution of the High Himalayan Crystalline of Zanskar

The geologic structures and metamorphic zonation of the northwestern Indian Himalaya contrast significantly with those in the central and eastern parts of the range, where the high-grade metamorphic rocks of the High Himalayan Crystalline (HHC) thrust southward over the weakly metamorphosed sediments of the Lesser Himalaya along the Main Central Thrust (MCT). Indeed, the hanging wall of the MCT in the NW Himalaya mainly consists of the greenschist facies metasediments of the Chamba zone, whereas HHC high-grade rocks are exposed more internally in the range as a large-scale dome called the Gianbul dome. This Gianbul dome is bounded by two oppositely directed shear zones, the NE-dipping Zanskar Shear Zone (ZSZ) on the northern flank and the SW-dipping Miyar Shear Zone (MSZ) on the southern limb. Current models for the emplacement of the HHC in NW India as a dome structure differ mainly in terms of the roles played by both the ZSZ and the MSZ during the tectonothermal evolution of the HHC. In both the channel flow model and wedge extrusion model, the ZSZ acts as a backstop normal fault along which the high-grade metamorphic rocks of the HHC of Zanskar are exhumed. In contrast, the recently proposed tectonic wedging model argues that the ZSZ and the MSZ correspond to one single detachment system that operates as a subhorizontal backthrust off of the MCT. Thus, the kinematic evolution of the two shear zones, the ZSZ and the MSZ, and their structural, metamorphic and chronological relations appear to be diagnostic features for discriminating the different models. In this paper, structural, metamorphic and geochronological data demonstrate that the MSZ and the ZSZ experienced two distinct kinematic evolutions. As such, the data presented in this paper rule out the hypothesis that the MSZ and the ZSZ constitute one single detachment system, as postulated by the tectonic wedging model. Structural, metamorphic and geochronological data are used to present an alternative tectonic model for the large-scale doming in the NW Indian Himalaya involving early NE-directed tectonics, weakness in the upper crust, reduced erosion at the orogenic front and rapid exhumation along both the ZSZ and the MSZ.

Trends in lung cancer among young European women: the rising epidemic in France and Spain.

Lung cancer mortality in young women in the European Union (EU) has steadily increased until the mid 1990 s and has levelled off thereafter, but trends have been heterogeneous in various countries. We analyzed therefore age-standardized trends in lung cancer mortality in young women (20-44) for the 6 major European countries, using joinpoint regression. In the early 1970s the highest lung cancer mortality in young women was in the UK (2.1/100,000). UK rates, however, steadily declined and in 2000-2004 they were the lowest of all 6 major EU countries (1.2/100,000). The second lowest rate in 2000-2002 was in Italy, whose rates remained around 1.1/100,000 between 1970 and 1994, and increased to 1.4 thereafter. In Germany and Poland, lung cancer rates in young women rose from 0.8-1.0/100,000 in the early 1970s to 1.7-1.9 in the mid 1990 s and levelled off during the last decade. Major rises over recent years were observed in France (from 0.8/100,000 in 1985-1989 to 2.2 in 2000-2003) and in Spain (from 0.8 in the 1985-1989 to 1.7 in 2000-2004). Thus, France showed both the highest rate observed over the last 3 decades and the largest rise over the last 2 decades. Since recent trends in the young give relevant information to the likely future trends in middle age, the female lung cancer epidemic is likely to expand in southern Europe from the current rates of 5.0/100,000 in Spain and 7.7 in France to approach 20/100,000 within the next 2-3 decades. Urgent interventions for smoking cessation in women are therefore required.

An epidemiological and clinical approach to adolescent suicide. A comparison between suicidal and non-suicidal clinical groups in a health foundation center for French students.

Suicidal behaviour among young people represents a major public health problem. This study seeks to compare the major sociological, clinical, schooling and family features of suicidal and non-suicidal subgroups of adolescents hospitalised in the Health Foundation Center for French Students of neufmoutiers en Brie (France). All these adolescents suffered from the severe mental disorders. The adolescents from the suicidal subgroup presented significantly fewer psychoses and more mood disorders than those of the non-suicidal subgroup. Half of the patients from the suicidal subgroup presented some features of personality disorders, mostly borderline personality disorders. Nevertheless, their global functioning was more frequently improved between admission and discharge than was the case for the non-suicidal group.