Assessing the two-dimensional behaviour of drystone retaining walls by full-scale experiments and yield design simulation

International audienceDrystone walling is a widespread form of construction that utilises local materials. It has received growing interest over the past few years, owing to the recognition of its rich heritage in the framework of sustainable development. However, the growth of dry masonry has been slowed by the lack of scientific evidence proving its reliability. The authors have previously established a model based on yield design to assess drystone wall stability. This theoretical approach has been supplemented by field experiments on full-scale drystone retaining walls that were backfilled until failure with a cohesionless soil. These field experiments followed a first set of experiments in 2002-2003 in which the walls were loaded using hydrostatic pressure. The aim of these experimental programmes was to achieve better understanding of drystone masonry behaviour under loading, and of its failure mode. The present paper consists of a comparative analysis of these theoretical and experimental results, and provides a richer understanding of drystone retaining wall phenomenology. Further perspectives on this work are presented in the conclusion

Effects of the nature of the doping salt and of the thermal pre-treatment and sintering temperature on spark plasma sintering of transparent alumina

A slurry of a-Al2O3 was doped with Mg, Zr and La nitrates or chlorides, in various amounts in the range 150-500 wt ppm and then freeze-dried to produce nanosized doped powder (~150 nm). The powder was sintered by SPS to yield transparent polycrystalline alpha alumina. The influence of the nature of the doping element and the starting salt, the thermal treatment before sintering and the sintering emperature on the transparency of the ceramics were investigated. The transparency of the ceramics of nanosized Al2O3 was shown to depend mainly on the way the powder was prepared, the nature of the doping salt also had an effect. Finally, a high real inline transmittance, reaching 48.1% was achieved after optimization

Comparison of health benefits between a high intensity interval training and a moderate intensity continuous training when performed in a nonlaboratory setting, in moderately obese women

The objective of this pilot study was to compare the effects of a high-intensity interval training (HIIT) and a moderate intensity continuous training (MICT) performed within a fitness center, on various health indices of 49 sedentary and moderately obese women (age 37 ± 7 years; BMI 32 ± 4 kg/m2) randomly assigned to supervised exercise on a cycle ergometer, 3 times/week, during 12 weeks, at 60% (MICT, n=24) or 85% (HIIT, n=25) of their heart rate reserve for weeks 5-12. Anthropometry, body composition, cardiorespiratory fitness, CRF (2 km-walking test estimated V; O2max), quality of life, QoL (SF-36 Questionnaire), eating behaviors (Three Factor Eating Questionnaire, TFEQ) and perceived health (Short Health Perceived Questionnaire, SHPQ) were obtained before and after training from 10 HIIT vs. 13 MICT participants who completed the program. At baseline, both groups showed similar characteristics, except for a better sleep quality (SHPQ) in MICT than in HIIT participants (p<0.005). Increases in CRF (+3 to +5%) and decreases in body weight (-2%) and thus BMI (-2.5 to -4.5%), waist girth (-4%) and fat mass (-6 to - 8%) were comparable (0.0001<p<0.05). The physical component score (SF-36), the cognitive restriction and hunger scores (TFEQ), and the perceived health items (SPHQ) were similarly improved, irrespective of the training mode (0.01<p<0.05). Twelve weeks of either HIIT or MICT led to similar body weight and fat mass losses as well as to comparable improvements in CRF, QoL, eating behaviors and perceived health, in healthy, sedentary and moderately obese women. However, the large dropout in the HIIT (58%; 14 of 24) and MICT (48%; 12 of 25) groups questions the implementation of such training programs within a non-laboratory setting. Further studies are clearly needed to better adapt the conditions of practice to subjects' characteristics and thus promote their long-term adherence to exercise

Architecture sociale et logiques capitalistes

Sophie Accolas – Pourquoi des architectes et des urbanistes contemporains maintiennent-ils un regard irénique (selon vos termes) sur la ville en privilégiant des représentations pacifiées et fantasmées ? Jean-Pierre Garnier – C’est, pourrait-on dire, parce que leur profes­sion le leur impose. Et cela à deux niveaux. D’abord, sur le plan psychologique. Les individus qui choisissent ce métier se doivent de considérer qu’ils peuvent, à leur échelle, « changer la ville pour changer la vie ». Sino..

Exploratory behaviour in NO-dependent cyclase mutants of Drosophila shows defects in coincident neuronal signalling

<p>Abstract</p> <p>Background</p> <p><it>Drosophila </it>flies explore the environment very efficiently in order to colonize it. They explore collectively, not individually, so that when a few land on a food spot, they attract the others by signs. This behaviour leads to aggregation of individuals and optimizes the screening of mates and egg-laying on the most favourable food spots.</p> <p>Results</p> <p>Flies perform cycles of exploration/aggregation depending on the resources of the environment. This behavioural ecology constitutes an excellent model for analyzing simultaneous processing of neurosensory information. We reasoned that the decision of flies to land somewhere in order to achieve aggregation is based on simultaneous integration of signals (visual, olfactory, acoustic) during their flight. On the basis of what flies do in nature, we designed laboratory tests to analyze the phenomenon of neuronal coincidence. We screened many mutants of genes involved in neuronal metabolism and the synaptic machinery.</p> <p>Conclusion</p> <p>Mutants of NO-dependent cyclase show a specifically-marked behaviour phenotype, but on the other hand they are associated with moderate biochemical defects. We show that these mutants present errors in integrative and/or coincident processing of signals, which are not reducible to the functions of the peripheral sensory cells.</p

Mental maps of students - Volume 5

This eurobroadmap working paper, split in 5 different volumes, presents the synthesis of a large survey launched in 2009 on 9000 undergraduate students from 18 different countries. The volume 1 includes the executive summary, plus elements regarding the five different volumes (references, list of figures, etc). The second one presents the aims and the organisation of the survey. The third one deals with the scale of the feeling of belonging. The fourth one presents explanatory models about countries and cities attractiveness. The final volume presents Europe representations in both cartographic and lexical ways

Rheumatoid arthritis seropositive for the rheumatoid factor is linked to the protein tyrosine phosphatase nonreceptor 22-620W allele

The protein tyrosine phosphatase nonreceptor type 22 (PTPN22) gene encodes for lymphoid tyrosine phosphatase LYP, involved in the negative regulation of early T-cell activation. An association has recently been reported between the PTPN22-620W functional allele and rheumatoid factor-positive (RF(+)) rheumatoid arthritis (RA), among other autoimmune diseases. Expected linkage proof for consistency cannot be definitely produced by an affected sib-pair (ASP) analysis. Our aim was therefore to search for linkage evidence with the transmission disequilibrium test. DNA from the French Caucasian population was available for two samples of 100 families with one RA patient and both parents, and for 88 RA index cases from RA ASP families. Genotyping was carried out by PCR-restriction fragment length polymorphism. The analysis was performed using the transmission disequilibrium test, genotype relative risk and ASP-based analysis. The transmission disequilibrium test of the PTPN22-620W allele revealed linkage and association for RF(+ )RA (61% of transmission, P = 0.037). The genotype relative risk showed the risk allele in 34% of RF(+ )RA patients and in 24% of controls derived from nontransmitted parental chromosomes (P = 0.047, odds ratio = 1.69, 95% confidence interval = 1.03–2.78). The ASP investigation showed no enriched risk allele in RA multiplex families, resulting in a lack of power of ASP analysis, explaining the published negative results. This study is the first to show linkage of PTPN22 to RF(+ )RA, consistent with PTPN22 as a new RA gene

Letter Regarding "Impact of the COVID-19 Pandemic on Training and Well-Being of Nephrology Residents in France and Belgium".

International audienc