Une pratique généraliste du service social informée par la neuroscience sociale : et pourquoi pas?

La place de la neuroscience dans le domaine de la santé n’est plus à faire. Les livres, les revues scientifiques ainsi que les magazines populaires font régulièrement référence à cette science pour expliquer le comportement humain. Plusieurs disciplines, des sciences infirmières à la psychoéducation en passant par l’économie et la philosophie, utilisent les connaissances issues de ce domaine. Mais quelle est la place actuelle de la neuroscience, plus précisément la neuroscience sociale, dans la pratique du service sociale ? Comment serait-il possible d’intégrer certaines connaissances de la neuroscience sociale à une pratique généraliste du service social tout en respectant la profession ? Ce mémoire vise à offrir quelques pistes de réflexion et d’intégration quant aux possibilités qu’offre la neuroscience sociale pour la pratique du service social.Maîtrise en Service Socia

Dynamic Mechanical Properties of PMMA/Organoclay Nanocomposite: Experiments and Modeling

Similarly to unfilled polymers, the dynamic mechanical properties of polymer/organoclay nanocomposites are sensitive to frequency and temperature, as well as to clay concentration

CorE from Myxococcus xanthus Is a Copper-Dependent RNA Polymerase Sigma Factor

The dual toxicity/essentiality of copper forces cells to maintain a tightly regulated homeostasis for this metal in all living organisms, from bacteria to humans. Consequently, many genes have previously been reported to participate in copper detoxification in bacteria. Myxococcus xanthus, a prokaryote, encodes many proteins involved in copper homeostasis that are differentially regulated by this metal. A σ factor of the ECF (extracytoplasmic function) family, CorE, has been found to regulate the expression of the multicopper oxidase cuoB, the P1B-type ATPases copA and copB, and a gene encoding a protein with a heavy-metal-associated domain. Characterization of CorE has revealed that it requires copper to bind DNA in vitro. Genes regulated by CorE exhibit a characteristic expression profile, with a peak at 2 h after copper addition. Expression rapidly decreases thereafter to basal levels, although the metal is still present in the medium, indicating that the activity of CorE is modulated by a process of activation and inactivation. The use of monovalent and divalent metals to mimic Cu(I) and Cu(II), respectively, and of additives that favor the formation of the two redox states of this metal, has revealed that CorE is activated by Cu(II) and inactivated by Cu(I). The activation/inactivation properties of CorE reside in a Cys-rich domain located at the C terminus of the protein. Point mutations at these residues have allowed the identification of several Cys involved in the activation and inactivation of CorE. Based on these data, along with comparative genomic studies, a new group of ECF σ factors is proposed, which not only clearly differs mechanistically from the other σ factors so far characterized, but also from other metal regulators

A worldwide survey on incidence, management and prognosis of oesophageal fistula formation following atrial fibrillation catheter ablation: The POTTER-AF study.

AIMS Oesophageal fistula represents a rare but dreadful complication of atrial fibrillation catheter ablation. Data on its incidence, management and outcome are sparse. METHODS AND RESULTS This international multicenter registry investigates the characteristics of oesophageal fistulae after treatment of atrial fibrillation by catheter ablation. A total of 553,729 catheter ablation procedures (radiofrequency: 62.9%, cryoballoon: 36.2%, other modalities: 0.9%) were performed at 214 centers in 35 countries. In 78 centers 138 patients (0.025%, radiofrequency: 0.038%, cryoballoon: 0.0015% (p<0.0001)) were diagnosed with an oesophageal fistula. Periprocedural data were available for 118 patients (85.5%). Following catheter ablation, the median time to symptoms and the median time to diagnosis were 18 (7.75, 25; range: 0-60) days and 21 (15, 29.5; range: 2-63) days, respectively. The median time from symptom onset to oesophageal fistula diagnosis was 3 (1, 9; range: 0-42) days. The most common initial symptom was fever (59.3%). The diagnosis was established by chest computed tomography in 80.2% of patients. Oesophageal surgery was performed in 47.4% and direct endoscopic treatment in 19.8%, and conservative treatment in 32.8% of patients. The overall mortality was 65.8%. Mortality following surgical (51.9%) or endoscopic treatment (56.5%) was significantly lower as compared to conservative management (89.5%) (odds ratio 7.463 (2.414, 23.072) p<0.001). CONCLUSIONS Oesophageal fistula after catheter ablation of atrial fibrillation is rare and occurs mostly with the use of radiofrequency energy rather than cryoenergy. Mortality without surgical or endoscopic intervention is exceedingly high

Co-limitation towards lower latitudes shapes global forest diversity gradients

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we produce a high-resolution (0.025° × 0.025°) map of local tree species richness using a global forest inventory database with individual tree information and local biophysical characteristics from ~1.3 million sample plots. We then quantify drivers of local tree species richness patterns across latitudes. Generally, annual mean temperature was a dominant predictor of tree species richness, which is most consistent with the metabolic theory of biodiversity (MTB). However, MTB underestimated LDG in the tropics, where high species richness was also moderated by topographic, soil and anthropogenic factors operating at local scales. Given that local landscape variables operate synergistically with bioclimatic factors in shaping the global LDG pattern, we suggest that MTB be extended to account for co-limitation by subordinate drivers

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Effect of Modified Eucalyptus nitens Lignin on the Morphology and Thermo-mechanical Properties of Recycled Polystyrene

The morphology and thermo-mechanical properties of recycled polystyrene-based materials (rPS) reinforced with 5 and 15% lignin from kraft pulping of Eucalyptus nitens were studied. The lignin was modified through two esterification processes using either acetic or maleic anhydride, and changes in the structure of the esterified lignin functional groups were analyzed by Fourier transform infrared spectroscopy. The lignin was then incorporated into rPS by melt mixing. Torque variation in the process was evaluated, and the values were compared to those of neat rPS and virgin PS. The results show a plasticizing effect of lignin with a reduction in the torque values. The morphology, studied through scanning electron microscopy, shows a particle size reduction of acetylated and maleated lignin and a more homogeneous dispersion at 5%. The thermal behavior of the composites, studied through differential scanning calorimetry, does not show significant changes in the glass-transition temperature of rPS with the presence of lignin. The dynamic mechanical analysis shows an increasing storage modulus with increasing lignin content. Thermal stability, studied through thermogravimetric analysis, improved for composites containing 5% esterified lignin. The flexural modulus also increased with lignin addition. These results suggest that the thermal and mechanical properties of post-consumer recycled polystyrene can be significantly improved with only 5% esterified lignin

Desempenho agronômico de genótipos de feijão‑caupi no sudoeste da Amazônia brasileira

The objective of this work was to evaluate the agronomic performance of cowpea (Vigna unguiculata) genotypes over three crop years, in the ecosystem of Rio Branco, in the state of Acre, Brazil. The experiments were carried out in the 2016, 2017, and 2018 crop seasons, in a randomized complete block design, with four replicates. Eight agronomic traits were evaluated in 14 cowpea genotypes, which included: 12 lines (BDO 1-5-11, BDO 1-5-15, BDO 1-5-19, BDO 1-5-24, PDO 1-5-26, PDO 1-5-4, PDO 1-5-5, PDO 1-5-7, PDO 1-5-8, PDO 1-5-10, PDO 1-5-11, and PDO 1-5-14) and two cultivars (BRS Tumucumaque and BRS Imponente). A significant difference was observed in the genotype x crop year interaction, for most traits. Although there was no statistical difference between genotypes in the studied crop years, dry seed productivity was higher than the national average. All cowpea lines and cultivars from the genetic breeding program show equivalent and favorable agronomic performances in the environmental conditions of Rio Branco. Therefore, these genotypes can be selected for incorporation into the production system of Rio Branco.O objetivo deste trabalho foi avaliar o desempenho agronômico de genótipos de feijão-caupi (Vigna unguiculata) em três anos agrícolas, no ecossistema de Rio Branco, no estado do Acre, Brasil. Os experimentos foram conduzidos nos anos agrícolas de 2016, 2017 e 2018, em delineamento de blocos ao acaso, com quatro repetições. Foram avaliados oito caracteres agronômicos, em 14 genótipos de feijão-caupi, que incluíram: 12 linhagens (BDO 1-5-11, BDO 1-5-15, BDO 1-5-19, BDO 1-5-24, PDO 1-5-26, PDO 1-5-4, PDO 1-5-5, PDO 1-5-7, PDO 1-5-8, PDO 1-5-10, PDO 1-5-11 e PDO 1-5-14) e duas cultivares (BRS Tumucumaque e BRS Imponente). Observou-se diferença significativa na interação genótipo x safra, para a maioria das características. Embora não tenha havido diferença estatística entre os genótipos nas safras estudadas, a produtividade de grãos secos foi superior à da média nacional. Todas as linhagens e as cultivares de feijão-caupi do programa de melhoramento genético apresentam desempenho agronômico equivalente e favorável nas condições ambientais de Rio Branco. Portanto, esses genótipos podem ser selecionados para incorporação ao sistema produtivo de Rio Branco