Une correspondance sépharade : 1794-96

De l’historiographie révolutionnaire émerge une image de la vie quotidienne bordelaise faite de chaos, de peur et d’incertitude, ainsi que de ruine économique et de désastre politique. Il est rarement question d’amitié entre personnes « ordinaires » ou même, du moins à partir de 1794, d’enthousiasme pour la Révolution elle-même. Et pourtant, pendant que l’économie bordelaise sombrait et que sa communauté marchande était en proie à une période de crise, une série de lettres entre trois négocia..

The cell adhesion molecule Fasciclin2 regulates brush border length and organization in Drosophila renal tubules

Multicellular organisms rely on cell adhesion molecules to coordinate cell–cell interactions, and to provide navigational cues during tissue formation. In Drosophila, Fasciclin 2 (Fas2) has been intensively studied due to its role in nervous system development and maintenance; yet, Fas2 is most abundantly expressed in the adult renal (Malpighian) tubule rather than in neuronal tissues. The role Fas2 serves in this epithelium is unknown. Here we show that Fas2 is essential to brush border maintenance in renal tubules of Drosophila. Fas2 is dynamically expressed during tubule morphogenesis, localizing to the brush border whenever the tissue is transport competent. Genetic manipulations of Fas2 expression levels impact on both microvilli length and organization, which in turn dramatically affect stimulated rates of fluid secretion by the tissue. Consequently, we demonstrate a radically different role for this well-known cell adhesion molecule, and propose that Fas2-mediated intermicrovillar homophilic adhesion complexes help stabilize the brush border

The Effect of Processing Variables on Powder Interlayer Bonding in Nickel-Based Superalloys

Powder Interlayer Bonding (PIB) has been considered as a lower-energy joining technology for nickel-based superalloys compared to conventional methods; such as friction welding. Typically; nickel-based superalloys exhibit high energy requirements for joining due to their high operating temperatures. However; PIB utilizes a localized temperature gradient created by an induction current; reducing the energy requirements for the process. PIB is a solid-state joining method that compresses and heats a powder interlayer between two faying surfaces to produce one joined workpiece. It has been successfully used to bond titanium alloys; and the objectives of this work were to explore its application as a joining method for nickel-based superalloys. Initial results showed that joining nickel-based superalloys via PIB is possible; and bondlines with very little porosity were observed. Further analysis showed that these bonded areas had lower porosity than the base material; suggesting PIB could be a successful joining method for difficult-to-join nickel-based superalloys

From catchment to national scale rainfall-runoff modelling: demonstration of a hydrological modelling framework

The increasing availability of digital databases (e.g. of climatology, topography, soils and land use) has enabled research into the generalisation of hydrological model parameter values from physical properties and the development of grid-based models. A hydrological modelling framework (HMF) is being developed to exploit this generalisation and provide a flexible gridded infrastructure, operational over regional, national or larger scales at a range of spatial and temporal resolutions. The capability of the framework is demonstrated through adaptation of an existing semi-distributed catchment-based rainfall-runoff model, CLASSIC, for which a generalised methodology exists to determine parameter values. The main change required was to ensure consistency of parameter values between the runoff procedure in CLASSIC and flow routing in the HMF. Assessment is by comparison of modelled and observed flow at grid points in Britain corresponding to gauging stations, both for catchments previously modelled and for new locations, for a range of catchment areas and physical properties and for four spatial resolutions (10, 5, 2.5 and 1 km). Good model performance is achieved for 90% of catchments tested, with a 5 km resolution proving adequate for catchments larger than 500 km2. Applications are outlined for which the framework could be used to test alternative modelling approaches or undertake consistent studies across the range of resolutions

Influence of Muscle-Tendon Wrapping on Calculations of Joint Reaction Forces in the Equine Distal Forelimb

The equine distal forelimb is a common location of injuries related to mechanical overload. In this study, a two-dimensional model of the musculoskeletal system of the region was developed and applied to kinematic and kinetic data from walking and trotting horses. The forces in major tendons and joint reaction forces were calculated. The components of the joint reaction forces caused by wrapping of tendons around sesamoid bones were found to be of similar magnitude to the reaction forces between the long bones at each joint. This finding highlighted the importance of taking into account muscle-tendon wrapping when evaluating joint loading in the equine distal forelimb

Using mixed methods evaluation to assess the feasibility of online clinical training in evidence based interventions : a case study of cognitive behavioural treatment for low back pain

Background: Cognitive behavioural (CB) approaches are effective in the management of non-specific low back pain (LBP). We developed the CB Back Skills Training programme (BeST) and previously provided evidence of clinical and cost effectiveness in a large pragmatic trial. However, practice change is challenged by a lack of treatment guidance and training for clinicians. We aimed to explore the feasibility and acceptability of an online programme (iBeST) for providing training in a CB approach. Methods: This mixed methods study comprised an individually randomised controlled trial of 35 physiotherapists and an interview study of 8 physiotherapists. Participants were recruited from 8 National Health Service departments in England and allocated by a computer generated randomisation list to receive iBeST (n = 16) or a face-to-face workshop (n = 19). Knowledge (of a CB approach), clinical skills (unblinded assessment of CB skills in practice), self-efficacy (reported confidence in using new skills), attitudes (towards LBP management), and satisfaction were assessed after training. Engagement with iBeST was assessed with user analytics. Interviews explored acceptability and experiences with iBeST. Data sets were analysed independently and jointly interpreted. Results: Fifteen (94 %) participants in the iBeST group and 16 (84 %) participants in the workshop group provided data immediately after training. We observed similar scores on knowledge (MD (95 % CI): 0.97 (−1.33, 3.26)), and self-efficacy to deliver the majority of the programme (MD (95 % CI) 0.25 (−1.7; 0.7)). However, the workshop group showed greater reduction in biomedical attitudes to LBP management (MD (95 % CI): −7.43 (−10.97, −3.89)). Clinical skills were assessed in 5 (33 %) iBeST participants and 7 (38 %) workshop participants within 6 months of training and were similar between groups (MD (95 % CI): 0.17(−0.2; 0.54)). Interviews highlighted that while initially sceptical, participants found iBeST acceptable. A number of strategies were identified to enhance future versions of iBeST such as including more skills practice. Conclusions: Combined quantitative and qualitative data indicated that online training was an acceptable and promising method for providing training in an evidence based complex intervention. With future enhancement, the potential reach of this training method may facilitate evidence-based practice through large scale upskilling of the workforce

Unspoken playground rules discourage adolescent physical activity in school : a focus group study of constructs in the Prototype Willingness Model

The health benefits of exercise in school are recognised, yet physical activity continues to decline during early adolescence despite numerous interventions. In this study we investigated whether the Prototype Willingness Model, an account of adolescent decision-making that includes both reasoned behavioural choices and unplanned responses to social environments, might improve understanding of physical activity in school. We conducted focus groups with British pupils aged 12-13 and used deductive thematic analysis to search for themes relating to the model. Participants described reasoned decisions about physical activity outside school and unplanned choices to be inactive during break, in response to social contexts described as more ‘judgmental’ than in primary school. Social contexts appeared characterised by anxiety about competence, negative peer evaluation and inactive playground norms. The Prototype Willingness Model might more fully explain physical activity in school than reasoned behavioural models alone, indicating potential for interventions targeting anxieties about playground social environments

Diffusion bonding of TiC or TiB reinforced Ti–6Al–4V matrix composites to conventional Ti–6Al–4V alloy

The diffusion bonding of conventional alloy Ti–6Al–4V (Ti-64) and composites of this alloy with 10% of TiC or TiB fabricated using blended elemental powder metallurgy was successfully carried out at 850–1000°C, with a holding time of 60 min under 0.7–1.5 MPa pressure. The metallographic and electron backscattered diffraction studies as well as the bending and microhardness tests across the bonds are presented as the evidence of joint integrity. The selected experimental parameters do not cause undesirable structural changes (degradation) in the base metals adjacent to the bond interface. Particle reinforcement at ∼10% did not appear to modify bonding parameters when compared to the unreinforced Ti-64 alloy

Spatial scaling properties of coral reef benthic communities

The spatial structure of ecological communities on tropical coral reefs across seascapes and geographies have historically been poorly understood. Here we addressed this for the first time using spatially expansive and thematically resolved benthic community data collected around five uninhabited central Pacific oceanic islands, spanning 6° latitude and 17° longitude. Using towed-diver digital image surveys over ~140 linear km of shallow (8–20 m depth) tropical reef, we highlight the autocorrelated nature of coral reef seascapes. Benthic functional groups and hard coral morphologies displayed significant spatial clustering (positive autocorrelation) up to kilometre-scales around all islands, in some instances dominating entire sections of coastline. The scale and strength of these autocorrelation patterns showed differences across geographies, but patterns were more similar between islands in closer proximity and of a similar size. For example, crustose coralline algae (CCA) were clustered up to scales of 0.3 km at neighbouring Howland and Baker Islands and macroalgae were spatially clustered at scales up to ~3 km at both neighbouring Kingman Reef and Palmyra Atoll. Of all the functional groups, macroalgae had the highest levels of spatial clustering across geographies at the finest resolution of our data (100 m). There were several cases where the upper scale at which benthic community members showed evidence of spatial clustering correlated highly with the upper scales at which concurrent gradients in physical environmental drivers were spatially clustered. These correlations were stronger for surface wave energy than subsurface temperature (regardless of benthic group) and turf algae and CCA had the closest alignments in scale with wave energy across functional groups and geographies. Our findings suggest such physical drivers not only limit or promote the abundance of various benthic competitors on coral reefs, but also play a key role in governing their spatial scaling properties across seascapes

Coccolithophore biodiversity controls carbonate export in the Southern Ocean

Southern Ocean waters are projected to undergo profound changes in their physical and chemical properties in the coming decades. Coccolithophore blooms in the Southern Ocean are thought to account for a major fraction of the global marine calcium carbonate (CaCO3) production and export to the deep sea. Therefore, changes in the composition and abundance of Southern Ocean coccolithophore populations are likely to alter the marine carbon cycle, with feedbacks to the rate of global climate change. However, the contribution of coccolithophores to CaCO3 export in the Southern Ocean is uncertain, particularly in the circumpolar subantarctic zone that represents about half of the areal extent of the Southern Ocean and where coccolithophores are most abundant. Here, we present measurements of annual CaCO3 flux and quantitatively partition them amongst coccolithophore species and heterotrophic calcifiers at two sites representative of a large portion of the subantarctic zone. We find that coccolithophores account for a major fraction of the annual CaCO3 export, with the highest contributions in waters with low algal biomass accumulations. Notably, our analysis reveals that although Emiliania huxleyi is an important vector for CaCO3 export to the deep sea, less abundant but larger species account for most of the annual coccolithophore CaCO3 flux. This observation contrasts with the generally accepted notion that high particulate inorganic carbon accumulations during the austral summer in the subantarctic Southern Ocean are mainly caused by E. huxleyi blooms. It appears likely that the climate-induced migration of oceanic fronts will initially result in the poleward expansion of large coccolithophore species increasing CaCO3 production. However, subantarctic coccolithophore populations will eventually diminish as acidification overwhelms those changes. Overall, our analysis emphasizes the need for species-centred studies to improve our ability to project future changes in phytoplankton communities and their influence on marine biogeochemical cycles.info:eu-repo/semantics/publishedVersio