Université Paris Nanterre

This revised edition includes a new Preface outlining developments in Relevance Theory since 1986, discussing the more serious criticisms of the theory, and ...

The density of states on a fractal is calculated taking into account the scaling properties of both the volume and the connectivity. We use a Green's function method developed elsewhere which utilizes a relationship to the diffusion problem. It is found that proper mode counting requires a reciprocal space with new intrinsic fracton dimensionality d = 2 d/(2 + δ). Here, d is the effective dimensionality, and δ the exponent giving the dependence of the diffusion constant on distance. For example, we find for percolation clusters d = 4/3 within the numerical accuracy available, independent of the Euclidean dimensionality d. Crossover to normal behaviour at low frequencies is discussed for finite fractals and for percolation above the percolation threshold pc. Relevance to experimental results on proteins is also discussed.

BACKGROUND: Public health recommendations and governmental measures during the COVID-19 pandemic have resulted in numerous restrictions on daily living including social distancing, isolation and home confinement. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on health behaviours and lifestyles at home is undefined. Therefore, an international online survey was launched in April 2020, in seven languages, to elucidate the behavioural and lifestyle consequences of COVID-19 restrictions. This report presents the results from the first thousand responders on physical activity (PA) and nutrition behaviours. METHODS: Following a structured review of the literature, the "Effects of home Confinement on multiple Lifestyle Behaviours during the COVID-19 outbreak (ECLB-COVID19)" Electronic survey was designed by a steering group of multidisciplinary scientists and academics. The survey was uploaded and shared on the Google online survey platform. Thirty-five research organisations from Europe, North-Africa, Western Asia and the Americas promoted the survey in English, German, French, Arabic, Spanish, Portuguese and Slovenian languages. Questions were presented in a differential format, with questions related to responses "before" and "during" confinement conditions. RESULTS: 1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%) were included in the analysis. The COVID-19 home confinement had a negative effect on all PA intensity levels (vigorous, moderate, walking and overall). Additionally, daily sitting time increased from 5 to 8 h per day. Food consumption and meal patterns (the type of food, eating out of control, snacks between meals, number of main meals) were more unhealthy during confinement, with only alcohol binge drinking decreasing significantly. CONCLUSION: While isolation is a necessary measure to protect public health, results indicate that it alters physical activity and eating behaviours in a health compromising direction. A more detailed analysis of survey data will allow for a segregation of these responses in different age groups, countries and other subgroups, which will help develop interventions to mitigate the negative lifestyle behaviours that have manifested during the COVID-19 confinement.

Die Geschwindigkeit der Reaktionen, welche von Elektrolyten (Säuren und Basen) bewirkt werden, steht in einem sehr engen Zusammenhange mit der elektrischen Leitfähigkeit derselben.Aus theoretischen Gründen wurde Proportionalität zwischen diesen beiden Grössen angenommen 1 ), und die nachher ausgeführten experimentellen Bestimmungen 8 ) zeigten, dass dies annähernd der Fall ist.Jedoch konnte diese Beziehung nicht strenge aufrecht erhalten werden.Nachdem man die Möglichkeit gefunden hatte, den

Die Geschwindigkeit der Reaktionen, welche von Elektrolyten (Säuren und Basen) bewirkt werden, steht in einem sehr engen Zusammenhange mit der elektrischen Leitfähigkeit derselben.Aus theoretischen Gründen wurde Proportionalität zwischen diesen beiden Grössen angenommen 1 ), und die nachher ausgeführten experimentellen Bestimmungen 8 ) zeigten, dass dies annähernd der Fall ist.Jedoch konnte diese Beziehung nicht strenge aufrecht erhalten werden.Nachdem man die Möglichkeit gefunden hatte, den

The study of school bullying has recently assumed an international dimension, but is faced with difficulties in finding terms in different languages to correspond to the English word bullying. To investigate the meanings given to various terms, a set of 25 stick-figure cartoons was devised, covering a range of social situations between peers. These cartoons were shown to samples of 8- and 14-year-old pupils (N = 1,245; n = 604 at 8 years, n = 641 at 14 years) in schools in 14 different countries, who judged whether various native terms cognate to bullying, applied to them. Terms from 10 Indo-European languages and three Asian languages were sampled. Multidimensional scaling showed that 8-year-olds primarily discriminated nonaggressive and aggressive cartoon situations; however, 14-year-olds discriminated fighting from physical bullying, and also discriminated verbal bullying and social exclusion. Gender differences were less appreciable than age differences. Based on the 14-year-old data, profiles of 67 words were then constructed across the five major cartoon clusters. The main types of terms used fell into six groups: bullying (of all kinds), verbal plus physical bullying, solely verbal bullying, social exclusion, solely physical aggression, and mainly physical aggression. The findings are discussed in relation to developmental trends in how children understand bullying, the inferences that can be made from cross-national studies, and the design of such studies.

Foreword 1. The Problem Defined: The Need for an Anthropology of Art 2. The Theory of the Art Nexus 3. The Art Nexus and the Index 4. The Involution of the Index in the Art Nexus 5. The Origination of the Index 6. The Critique of the Index 7. The Distributed Person 8. Style and Culture 9. Conclusion: The Extended Mind Bibliography Index

Though key to fostering innovation, interpersonal exchanges of resources between R&D scientists across organizational boundaries can represent intellectual capital leaks. A grounded theoretical fra...

BACKGROUND: Applying the concept of burnout to medical students before residency is relatively recent. Its estimated prevalence varies significantly between studies. Our objective was to estimate the prevalence of burnout in medical students worldwide. METHODS: We systematically searched Medline for English-language articles published between January 1, 2010 and December 31, 2017. We selected all the original studies about the prevalence of burnout in medical students before residency, using validated questionnaires for burnout. Statistical analyses were conducted using the OpenMetaAnalyst software. RESULTS: Prevalence of current burnout was extracted from 24 studies encompassing 17,431 medical students. Among them, 8060 suffered from burnout and we estimated the prevalence to be 44.2% [33.4%-55.0%]. The information about the prevalence of each subset of burnout dimensions was given in nine studies including 7588 students. Current prevalence was estimated to be 40.8% for 'emotional exhaustion' [32.8%-48.9%], 35.1% [27.2%-43.0%] for 'depersonalization' and 27.4% [20.5%-34.3%] for 'personal accomplishment'. There is no significant gender difference in burnout. The prevalence of burnout is slightly different across countries with a higher prevalence in Oceania and the Middle East than in other continents. CONCLUSIONS: The results of this meta-analysis suggest that one student out of two is suffering from burnout, even before residency. Again, our findings highlight the high level of distress in the medical population. These results should encourage the development of preventive strategies.

Abstract Arabinosyl cytosine (ara-C), a synthetic pyrimidine nucleoside related to the normal metabolites cytidine and deoxycytidine, has been found capable of producing marrow remission at tolerable doses in acute myelocytic and acute lymphocytic leukemia in adults. There were 16 per cent remissions complete in all aspects, 3 per cent complete except for hemoglobin level, and 6 per cent partial remissions among 180 adults with acute myelocytic leukemia treated with any one of 8 variants of infusion duration or daily dose of ara-C. Twenty-four per cent of 37 adults with acute lymphocytic or unclassified leukemia had complete or partial remissions. The comparison of 1, 4, 12 and 24 hours infusion of ara-C (to total dose tolerated) does not show significant superiority for any one group. The complete remission rate with 1 or 12 hour infusions, however, is 25 per cent (superior to that obtained with 6-mercaptopurine) and the recommended schedule of treatment for ara-C based on these data is, therefore, daily infusions of 100 or 50 mg./m.2 in one hour for approximately 3 to 6 weeks followed by maintenance therapy of once weekly subcutaneous injection of 30 mg./m.2 of ara-C. Platelet transfusions should be available when ara-C is used.

This study aimed to validate a simple field method for determining force- and power-velocity relationships and mechanical effectiveness of force application during sprint running. The proposed method, based on an inverse dynamic approach applied to the body center of mass, estimates the step-averaged ground reaction forces in runner's sagittal plane of motion during overground sprint acceleration from only anthropometric and spatiotemporal data. Force- and power-velocity relationships, the associated variables, and mechanical effectiveness were determined (a) on nine sprinters using both the proposed method and force plate measurements and (b) on six other sprinters using the proposed method during several consecutive trials to assess the inter-trial reliability. The low bias (<5%) and narrow limits of agreement between both methods for maximal horizontal force (638 ± 84 N), velocity (10.5 ± 0.74 m/s), and power output (1680 ± 280 W); for the slope of the force-velocity relationships; and for the mechanical effectiveness of force application showed high concurrent validity of the proposed method. The low standard errors of measurements between trials (<5%) highlighted the high reliability of the method. These findings support the validity of the proposed simple method, convenient for field use, to determine power, force, velocity properties, and mechanical effectiveness in sprint running.

BACKGROUND: The combination of multiple cycles of rituximab and intravenous immune globulins has been reported to be effective in patients with severe pemphigus. The aim of this study was to assess the efficacy of a single cycle of rituximab in severe types of pemphigus. METHODS: We studied 21 patients with pemphigus whose disease had not responded to an 8-week course of 1.5 mg of prednisone per kilogram of body weight per day (corticosteroid-refractory disease), who had had at least two relapses despite doses of prednisone higher than 20 mg per day (corticosteroid-dependent disease), or who had severe contraindications to corticosteroids. The patients were treated with four weekly infusions of 375 mg of rituximab per square meter of body-surface area. The primary end point was complete remission 3 months after the end of rituximab treatment; complete remission was defined as epithelialization of all skin and mucosal lesions. RESULTS: Eighteen of 21 patients (86%; 95% confidence interval, 64 to 97%) had a complete remission at 3 months. The disease relapsed in nine patients after a mean of 18.9+/-7.9 months. After a median follow-up of 34 months, 18 patients (86%) were free of disease, including 8 who were not receiving corticosteroids; the mean prednisone dose decreased from 94.0+/-10.2 to 12.0+/-7.5 mg per day (P=0.04) in patients with corticosteroid-refractory disease and from 29.1+/-12.4 to 10.9+/-16.5 mg per day (P=0.007) in patients with corticosteroid-dependent disease. Pyelonephritis developed in one patient 12 months after rituximab treatment, and one patient died of septicemia 18 months after rituximab treatment. These patients had a profound decrease in the number of circulating B lymphocytes but normal serum levels of IgG. CONCLUSIONS: A single cycle of rituximab is an effective treatment for pemphigus. Because of its potentially severe side effects, its use should be limited to the most severe types of the disease. (ClinicalTrials.gov number, NCT00213512 [ClinicalTrials.gov].).

Most people hold beliefs about personality characteristics typical of members of their own and others' cultures. These perceptions of national character may be generalizations from personal experience, stereotypes with a "kernel of truth," or inaccurate stereotypes. We obtained national character ratings of 3989 people from 49 cultures and compared them with the average personality scores of culture members assessed by observer ratings and self-reports. National character ratings were reliable but did not converge with assessed traits. Perceptions of national character thus appear to be unfounded stereotypes that may serve the function of maintaining a national identity.

Ancient migrations in Southeast Asia The past movements and peopling of Southeast Asia have been poorly represented in ancient DNA studies (see the Perspective by Bellwood). Lipson et al. generated sequences from people inhabiting Southeast Asia from about 1700 to 4100 years ago. Screening of more than a hundred individuals from five sites yielded ancient DNA from 18 individuals. Comparisons with present-day populations suggest two waves of mixing between resident populations. The first mix was between local hunter-gatherers and incoming farmers associated with the Neolithic spreading from South China. A second event resulted in an additional pulse of genetic material from China to Southeast Asia associated with a Bronze Age migration. McColl et al. sequenced 26 ancient genomes from Southeast Asia and Japan spanning from the late Neolithic to the Iron Age. They found that present-day populations are the result of mixing among four ancient populations, including multiple waves of genetic material from more northern East Asian populations. Science , this issue p. 92 , p. 88 ; see also p. 31

Public health recommendations and governmental measures during the new coronavirus disease (COVID-19) pandemic have enforced numerous restrictions on daily living including social distancing, isolation, and home confinement. While these measures are imperative to mitigate spreading of COVID-19, the impact of these restrictions on psychosocial health is undefined. Therefore, an international online survey was launched in April 2020 to elucidate the behavioral and lifestyle consequences of COVID-19 restrictions. This report presents the preliminary results from more than one thousand responders on social participation and life satisfaction. Methods: Thirty-five research organizations from Europe, North-Africa, Western Asia, and the Americas promoted the survey through their networks to the general society, in 7 languages (English, German, French, Arabic, Spanish, Portuguese, and Slovenian). Questions were presented in a differential format with questions related to responses “before” and “during” confinement conditions. Results: 1047 participations (54% women) from Asia (36%), Africa (40%), Europe (21%), and others (3%) were included in the analysis. Findings revealed psychosocial strain during the enforced COVID-19 home confinement. Large decreases (p &lt; 0.001) in the amount of social activity through family (−58%), friends/neighbors (−44.9%), or entertainment (−46.7%) were triggered by the enforced confinement. These negative effects on social participation were also associated with lower life satisfaction (−30.5%) during the confinement period. Conversely, the social contact score through digital technologies significantly increased (p &lt; 0.001) during the confinement period with more individuals (+24.8%) being socially connected through digital technology. Conclusion: These preliminary findings elucidate the risk of psychosocial strain during the early COVID-19 home confinement period in 2020. Therefore, in order to mitigate the negative psychosocial effects of home confinement, implementation of national strategies focused on promoting social inclusion through a technology-based solution is strongly suggested.

Geometric-phase metasurfaces, recently utilized for controlling wavefronts of circular polarized (CP) electromagnetic waves, are drastically limited to the cross-polarization modality. Combining geometric with propagation phase allows to further control the co-polarized output channel, nevertheless addressing only similar functionality on both co-polarized outputs for the two different CP incident beams. Here we introduce the concept of chirality-assisted phase as a degree of freedom, which could decouple the two co-polarized outputs, and thus be an alternative solution for designing arbitrary modulated-phase metasurfaces with distinct wavefront manipulation in all four CP output channels. Two metasurfaces are demonstrated with four arbitrary refraction wavefronts, and orbital angular momentum modes with four independent topological charge, showcasing complete and independent manipulation of all possible CP channels in transmission. This additional phase addressing mechanism will lead to new components, ranging from broadband achromatic devices to the multiplexing of wavefronts for application in reconfigurable-beam antenna and wireless communication systems.

The objective of this study was to characterize the mechanics of maximal running sprint acceleration in high-level athletes. Four elite (100-m best time 9.95-10.29 s) and five sub-elite (10.40-10.60 s) sprinters performed seven sprints in overground conditions. A single virtual 40-m sprint was reconstructed and kinetics parameters were calculated for each step using a force platform system and video analyses. Anteroposterior force (FY), power (PY), and the ratio of the horizontal force component to the resultant (total) force (RF, which reflects the orientation of the resultant ground reaction force for each support phase) were computed as a function of velocity (V). FY-V, RF-V, and PY-V relationships were well described by significant linear (mean R(2) of 0.892 ± 0.049 and 0.950 ± 0.023) and quadratic (mean R(2) = 0.732 ± 0.114) models, respectively. The current study allows a better understanding of the mechanics of the sprint acceleration notably by modeling the relationships between the forward velocity and the main mechanical key variables of the sprint. As these findings partly concern world-class sprinters tested in overground conditions, they give new insights into some aspects of the biomechanical limits of human locomotion.

The five-factor model (FFM) is a representation of the patterns of covariation of personality traits in terms of five broad factors. The Revised NEO Personality Inventory, a questionnaire measure of the FFM, has recently been translated into a number of different languages, permitting tests of its cross-cultural replicability. Data from Filipino and French translations are presented, showing clear and detailed replication of the American normative factor structure when targeted rotation is used. Results from these and other cross-cultural and behavior genetic studies suggest that the FFM is a biologically based human universal. Applications of trait psychology in clinical, educational, and organizational settings may prove generalizable across cultures, and cross-cultural psychologists can profitably explore the expression of the same personality traits in different cultural contexts.

This book examines “the great contraction” of 2007–2010 within the context of the neoliberal globalization that began in the early 1980s. This new phase of capitalism greatly enriched the top 5 percent of Americans, including capitalists and financial managers, but at a significant cost to the country as a whole. Declining domestic investment in manufacturing, unsustainable household debt, rising dependence on imports and financing, and the growth of a fragile and unwieldy global financial structure threaten the strength of the dollar. Unless these trends are reversed, the authors predict, the U.S. economy will face sharp decline. Summarizing a large amount of troubling data, the authors show that manufacturing has declined from 40 percent of GDP to under 10 percent in thirty years. Since consumption drives the American economy and since manufactured goods comprise the largest share of consumer purchases, clearly we will not be able to sustain the accumulating trade deficits. Rather than blame individuals, such as Greenspan or Bernanke, the authors focus on larger forces. Repairing the breach in our economy will require limits on free trade and the free international movement of capital; policies aimed at improving education, research, and infrastructure; reindustrialization; and the taxation of higher incomes.

Exact spectra of periodic samples are computed up to N=36. Evidence of an extensive set of low-lying levels, lower than the softest magnons, is exhibited. These low-lying quantum states are degenerated in the thermodynamic limit; their symmetries and dynamics as well as their finite-size scaling are strong arguments in favor of N\'eel order. It is shown that the N\'eel order parameter agrees with first-order spin-wave calculations. A simple explanation of the low-energy dynamics is given as well as the numerical determinations of the energies, order parameter, and spin susceptibilities of the studied samples. It is shown how suitable boundary conditions, which do not frustrate N\'eel order, allow the study of samples with N=3p+1 spins. A thorough study of these situations is done in parallel with the more conventional case N=3p.