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Abstract Collectively locomoting animals are often viewed as analogous to states of matter in that group-level phenomena emerge from individual-level interactions. Applying this framework to fish schools and bird flocks must account for visco-inertial flows as mediators of the physical interactions. Motivated by linear flight formations, here we show that pairwise flow interactions tend to promote crystalline or lattice-like arrangements, but such order is disrupted by unstably growing positional waves. Using robotic experiments on “mock flocks” of flapping wings in forward flight, we find that followers tend to lock into position behind a leader, but larger groups display flow-induced oscillatory modes – “flonons” – that grow in amplitude down the group and cause collisions. Force measurements and applied perturbations inform a wake interaction model that explains the self-ordering as mediated by spring-like forces and the self-amplification of disturbances as a resonance cascade. We further show that larger groups may be stabilized by introducing variability among individuals, which induces positional disorder while suppressing flonon amplification. These results derive from generic features including locomotor-flow phasing and nonreciprocal interactions with memory, and hence these phenomena may arise more generally in macroscale, flow-mediated collectives.

This article talks about the science of social education with the primary education system that has been the subject of social construction in Madagascar. Madagascar, starting from education based on traditional education, also opting for the evolution of modern education as in the whole world. the article analyzes the evolution of the life of the society which adopts this traditional education to those of the new education. the students are heirs of the culture but the stakes related to the socio-political vagaries, the new methods, and the traditional method remains predominant in teaching practices and favors this traditional educational practice.

This paper systematically addresses different concepts of anomy and norms among young men from selected groups in society. Government authorities in Madagascar who are responsible for public education are concerned about the social changes we are experiencing collectively. They have a more elaborate and better vision to guide young people in a professional and social world. In this perspective, they recognize that globalization, for example, is gradually creating a new phenomenon, in this case: technology. Many people believe that citizenship education enables adolescents to cope with these changes, since from this perspective, the child from birth is seen as part of a community, to whom he or she will eventually contribute. Citizenship is a mechanism that consolidates and convinces the future citizen of the importance of his social and political involvement and the valorization of his identity roots.

Active particles added to a material control its internal activity. Here the authors investigate such a system and control the annealing of a colloidal crystal, the dynamics of which depend on the persistence of the motion of active particles.

À Madagascar, le Tsiperifery, une espèce de poivrier sauvage endémique de l’île, est actuellement soumis à une surexploitation. Un programme participatif de domestication de cette plante a été lancé pour assurer la durabilité de son exploitation. Des techniques de culture sont co-construites par des chercheurs et des paysans sur trois sites pilotes. Cette étude s’intéresse aux facteurs influençant la propension des paysans à co-construire et expérimenter ces techniques. Les données collectées via 90 entretiens semi-dirigés ont été traitées en suivant les principes de l’approche « grounded theory ». Les principaux déterminants influençant le comportement des paysans sont (i) la logique économique, (ii) le contexte informationnel, (iii) l’accès au marché, (iv) les capacités productives de l’exploitation et (v) l’esprit de conservation de la nature. À partir de ces déterminants, nous avons pu définir cinq types de stratégies paysannes : les « homo-economicus » ; les « conservationnistes » ; les « opportunistes », les « exclus » et les « suiveurs ». Cette meilleure compréhension des stratégies paysannes permet d’améliorer la conception et la conduite des programmes de recherche participative.

The effects of solvent vapor on spin-coated films of a polymorphic phthalocyanine derivative were investigated. Growth of single crystal films via redissolving organic films under solvent vapor was revealed by in situ microscopic observations of the films. X-ray diffraction measurement of the films after exposing to solvent vapor revealed the phase transition of polymorphs under solvent vapor. The direction of crystal growth was clarified by measuring the crystal orientation in a grown monodomain film. The mechanism of crystal growth based on redissolving organic films under solvent vapor was discussed in terms of the different solubilities of the polymorphs.

Copyright of Néphrologie & Thérapeutique is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Néphrologie & Thérapeutique is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We analyzed, by home blood pressure (BP) self-measurement and conventional predialytic measurement of BP, a cohort of haemodialysis patients in two hospital units between 2008 and 2010. All patients who already own a BP self-measurement device were included in this study. BP was recorded by the two methods for one week. The number of patients with a validated self-measurement device was 69 of 350 (21%) and 60 patients were included in analyses. These patients were divided into 23 (38%) permanent uncontrolled hypertensive (elevated BP at home and in hospital), 13 (22%) masked hypertensive (normal BP in hospital and elevated at home), eight (13%) white coat hypertensive (elevated BP in hospital and normal at home), and 16 (27%) permanent controlled normotensive (normal BP in hospital and at home). Patient compliance with all the self BP measurements was 95%. We did not find in this cohort the factors associated with masked hypertension in the general population such as being male, smoking and high body mass index. These results obtained in an in-hospital dialysis unit should be extrapolated with caution to all haemodialysis patients. However it is, to our knowledge, the first study on home BP self-measurement published in patients undergoing haemodialysis in France. A significant proportion of patients have masked hypertension. This should alert clinicians because of the poor cardiovascular prognosis associated with masked hypertension., (Copyright © 2011 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.)

The treatment of a patient with 131I at activity over 740 mega Becquerel (MBq) must be performed in a nuclear medicine department. Isolation is stopped if the patient radiation level is less than 20 muSv/hour at one meter. As regards patients with chronic renal failure treated with hemodialysis (HD), the first HD session will eliminate the major part of the radioactivity. French regulations do not give definite recommendations for this session. However, it imposes to collect liquid and solid wastes contaminated by radioactivity. Thus, it seems necessary to collect dialysate and solid wastes and to stock them in a room dedicated to radiation decay. The risk for dialysis staff is to be contaminated by an accidental ingestion of a biologic fluid from the patient. The usual protection barriers used during the HD session are sufficient: mask, gloves, overgarments, cap. There is no risk linked to external exposure to radiations. The maximal theoretical dose received by the staff during the session is 65 muSv, while annual maximal dose for public exposed to radiations is 1000 muSv. Although the dosimetric follow-up of dialysis staff is not mandatory, the nuclear medicine department of Marseille University Hospital has decided to do it in an information perspective. The session is performed in the presence of a radiation safety technician who gives film badges and active dosimeters to the dialysis staff. He reports the dialysis staff to the nuclear safety agency (Autorité de sûreté nucléaire).