Estimation des propriétés de rétention en eau des sols : Utilisation de classes de pédotransfert après stratifications texturale et texturo-structurale

Un programme de mesures des propriétés de rétention en eau des sols a été développé par l'INRA depuis une dizaine d'années afin de constituer un jeu de données qui puisse être utilisé pour tester les fonctions de pédotransfert (FPT) qui ont été proposées dans la littérature, en établir de nouvelles si celles proposées se révèlent non satisfaisantes et dans ce dernier cas, tester les nouvelles FPT. Dans ce contexte général et partant du constat que les FPT proposées ne permettent pas de prédire les propriétés de rétention en eau de façon satisfaisante, cette étude se propose de suivre une autre voie que celle habituellement suivie pour établir un outil d'estimation des propriétés de rétention en eau. Des classes de pédotransfert (CPT) sont proposées par classe de texture ou par classe combinant texture et structure, cette dernière étant renseignée à l'aide de la densité apparente déterminée sur des mottes de dimensions centimétriques. Ainsi, en utilisant soit la texture seule, soit la texture et la densité apparente de motte, on dispose des teneurs en eau massiques à –10, –33, –100, –330, –1000, –3 300 et –15 000 hPa en fonction de l'appartenance de l'horizon à telle ou telle classe de texture ou, telle ou telle classe combinant texture et densité apparente de motte. La qualité de la prédiction a été testée sur un échantillon de validation ; elle a aussi été comparée à celle qui aurait été obtenue si l'on avait utilisé les CPT de Jamagne et al. (1977). Par rapport à ces CPT, les résultats montrent une importante réduction du biais et un accroissement de la précision lorsque l'on utilise les CPT par classe de texture proposées dans cette étude. Lorsque l'on compare les CPT par classes texturales aux CPT par classes texturo-structurales, il n'y a pas d'amélioration notable du biais mais celui-ci était déjà très faible avec les CPT par classes texturales. En revanche, les CPT par classes texturo-structurales, qui permettent de tenir compte à la fois de la texture et de l'état structural du sol, améliorent la précision des prédictions. Pour les CPT par classes texturales, des teneurs en eau volumiques sont déduites des teneurs en eau massiques en utilisant la densité apparente de l'horizon. Les paramètres du modèle de van Genuchten sont donnés pour chaque classe de CPT. Une démarche permettant de prédire les propriétés de rétention en eau d'un horizon est proposée

Genomic analysis of serogroup Y Neisseria meningitidis isolates reveals extensive similarities between carriage and disease-associated organisms

Background. Neisseria meningitidis is a frequent colonizer of the human nasopharynx with asymptomatic carriage providing the reservoir for invasive, disease-causing strains. Serogroup Y (MenY) strains are a major cause of meningococcal disease. High resolution genetic analyses of carriage and disease isolates can establish epidemiological relationships and identify potential virulence factors. Methods. Whole genome sequence data were obtained from UK MenY carriage isolates from 1997-2010 (n=99). Sequences were compared to those from MenY invasive isolates from 2010 and 2011 (n=73) using a gene-by-gene approach. Results. Comparisons across 1,605 core genes resolved 91% of isolates into one of eight clusters containing closely related disease and carriage isolates. Six clusters contained carried meningococci isolated in 1997-2001 suggesting temporal stability. One cluster of isolates, predominately sharing the designation Y: P1.5-1,10-1: F4-1: ST-1655 (cc23), was resolved into a sub-cluster with 86% carriage isolates and a second with 90% invasive isolates. These subclusters were defined by specific allelic differences in five core genes encoding glycerate kinase (glxK), valine-pyruvate transaminase (avtA), superoxide dismutase (sodB) and two hypothetical proteins. Conclusions. High resolution genetic analyses detected long-term temporal stability and temporally-overlapping carriage and disease populations for MenY clones but also evidence of a disease-associated clone

Atomic Configuration of Nitrogen Doped Single-Walled Carbon Nanotubes

Having access to the chemical environment at the atomic level of a dopant in a nanostructure is crucial for the understanding of its properties. We have performed atomically-resolved electron energy-loss spectroscopy to detect individual nitrogen dopants in single-walled carbon nanotubes and compared with first principles calculations. We demonstrate that nitrogen doping occurs as single atoms in different bonding configurations: graphitic-like and pyrrolic-like substitutional nitrogen neighbouring local lattice distortion such as Stone-Thrower-Wales defects. The stability under the electron beam of these nanotubes has been studied in two extreme cases of nitrogen incorporation content and configuration. These findings provide key information for the applications of these nanostructures.Comment: 25 pages, 13 figure

Hamiltonian BRST deformation of a class of n-dimensional BF-type theories

Consistent Hamiltonian interactions that can be added to an abelian free BF-type class of theories in any n greater or equal to 4 spacetime dimensions are constructed in the framework of the Hamiltonian BRST deformation based on cohomological techniques. The resulting model is an interacting field theory in higher dimensions with an open algebra of on-shell reducible first-class constraints. We argue that the Hamiltonian couplings are related to a natural structure of Poisson manifold on the target space.Comment: 27 pages, uses JHEP3.cl

Social preferences, accountability, and wage bargaining

We assess the extent of preferences for employment in a collective wage bargaining situation with heterogeneous workers. We vary the size of the union and introduce a treatment mechanism transforming the voting game into an individual allocation task. Our results show that highly productive workers do not take employment of low productive workers into account when making wage proposals, regardless of whether insiders determine the wage or all workers. The level of pro-social preferences is small in the voting game, while it increases as the game is transformed into an individual allocation task. We interpret this as an accountability effect

Smart continence care for people with profound intellectual and multiple disabilities:Protocol for a cluster randomized trial and trial-based economic evaluation

Background: People with profound intellectual and multiple disabilities (PIMD) cannot communicate the need to change their incontinence products. The smart continence care (SCC) product Abena Nova signals caregivers when change is needed. This provides the opportunity for more person-centered care, increased quality of life, and a decreased number of leakages. However, there is a need for evidence of the effectiveness and cost-effectiveness of such technology compared with regular continence care (RCC) for people with PIMD. Objective: This paper presents the research protocol for an effectiveness and cost-effectiveness study with people with PIMD living in long-term care facilities in the Netherlands. Methods: A cluster randomized trial will be conducted in 3 consecutive waves across 6 long-term care providers for people with disabilities and 160 participants with PIMD. Long-term care providers are randomized at a 1:1 ratio, resulting in an intervention group and a group continuing RCC. The intervention group will receive implementation guidance and use SCC for 3 months; the other group will continue their RCC as usual and then switch to SCC. This study consists of three components: effectiveness study, economic evaluation, and process evaluation. The primary outcome will be a change in the number of leakages. The secondary outcomes are quality of life, the difference in the number of changes, the work perception of caregivers, cost-effectiveness, and cost utility. Data collection will occur at T0 (baseline), T1 (6 weeks), T2 (12 weeks), and T3 (9-month follow-up) for the first 2 intervention groups. An intention-to-treat analysis will be performed. The economic evaluation will be conducted alongside the trial from the societal and long-term care provider perspectives. Qualitative data collection through interviews and field notes will complement these quantitative results and provide input for the process evaluation. Results: This research was funded in December 2019 by ZonMw, the Netherlands Organization for Health Research and Development. As of June 2022, we enrolled 118 of the 160 participants. The enrollment of participants will continue in the third and fourth quarters of 2022. Conclusions: This study will provide insights into the effectiveness and cost-effectiveness of SCC for people with PIMD, allowing long-term care providers to make informed decisions about implementing such a technology. This is the first time that such a large-scale study is being conducted for people with PIMD

Zinc-gallium oxynitride powders: effect of the oxide precursor synthesis route

International audienceZinc-gallium oxynitride powders (ZnGaON) were synthesized by nitridation of ZnGa2O4 oxide precursor obtained by polymeric precursors (PP) and solid state reaction (SSR) methods and the influence of the synthesis route of ZnGa2O4 on the final compound ZnGaON was investigated. Crystalline single phase ZnGa2O4 was obtained at 1100 oC / 12 h by SSR and at 600 oC / 2 h by PP with different grain sizes and specific surface areas according to the synthesis route. After nitridation, ZnGaON oxynitrides with a GaN würtzite-type structure were obtained in both cases, however at lower temperatures for PP samples. The microstructure and the specific surface area were strongly dependent on the oxide synthesis method and on the nitridation temperature (42 m2g-1 and 5 m2g-1 for PP and SSR oxides treated at 700 °C, respectively). The composition analyses showed a strong loss of Zn for the PP samples, favored by the increase of ammonolysis temperature and by the higher specific surface area

Oral contraceptives, depressive and insomnia symptoms in adult women with and without depression

Background: Worldwide, oral contraceptive (OC) use is a very common form of birth control, although it has been associated with symptoms of depression and insomnia. Insomnia is a risk factor for major depressive disorder (MDD) but may also be a symptom of the disorder. Despite the large number of women who use OC, it is yet unknown whether women with previous or current diagnosis of depression are more likely to experience more severe depressive and insomnia symptoms during concurrent OC use than women without diagnosis of depression. Aim: This study examined associations between OC use and concurrent symptoms of depression (including atypical depression) and insomnia as well as between OC and prevalences of concurrent dysthymia and MDD. Participants were adult women with and without a history of MDD or dysthymia. We hypothesized that OC use is associated with concurrent increased severity of depressive symptoms and insomnia symptoms, as well as with an increased prevalence of concurrent diagnoses of dysthymia and MDD. We also hypothesized that a history of MDD or dysthymia moderates the relationship between OC use and depressive and insomnia symptoms. Methods: Measurements from premenopausal adult women from the Netherlands Study of Depression and Anxiety (NESDA) were grouped, based on whether participants were using OC or naturally cycling (NC). OC use, timing and regularity of the menstrual cycle were assessed with a structured interview, self-reported symptoms of depression (including atypical depression), insomnia with validated questionnaires, and MDD and dysthymia with structured diagnostic interviews. Results: We included a total of 1301 measurements in women who reported OC use and 1913 measurements in NC women (mean age 35.6, 49.8% and 28.9% of measurements in women with a previous depression or current depression, respectively). Linear mixed models showed that overall, OC use was neither associated with more severe depressive symptoms (including atypical depressive symptoms), nor with higher prevalence of diagnoses of MDD or dysthymia. However, by disentangling the amalgamated overall effect, within-person estimates indicated increased depressive symptoms and depressive disorder prevalence during OC use, whereas between-person estimated indicated lower depressive symptoms and prevalence of depressive disorders. OC use was consistently associated with more severe concurrent insomnia symptoms, in the overall estimates as well as in the within-person and between-person estimates. Presence of current or previous MDD or dysthymia did not mod-erate the associations between OC use and depressive or insomnia symptoms. Discussion: The study findings showed consistent associations between OC use and more severe insomnia symptoms, but no consistent associations between OC and depressive symptoms or diagnoses. Instead, post-hoc analyses showed that associations between OC and depression differed between within-and between person -estimates. This indicates that, although OC shows no associations on the overall level, some individuals might experience OC-associated mood symptoms. Our findings underscore the importance of accounting for individual differences in experiences during OC use. Furthermore, it raises new questions about mechanisms underlying associations between OC, depression and insomnia.Stress-related psychiatric disorders across the life spa

Influence of the combination and phase variation status of the haemoglobin receptors HmbR and HpuAB on meningococcal virulence

Neisseria meningitidis can utilize haem, haemoglobin and haemoglobin–haptoglobin complexes as sources of iron via two TonB-dependent phase variable haemoglobin receptors, HmbR and HpuAB. HmbR is over-represented in disease isolates, suggesting a link between haemoglobin acquisition and meningococcal disease. This study compared the distribution of HpuAB and phase variation (PV) status of both receptors in disease and carriage isolates. Meningococcal disease (n = 214) and carriage (n = 305) isolates representative of multiple clonal complexes (CCs) were investigated for the distribution, polyG tract lengths and ON/OFF status of both haemoglobin receptors, and for the deletion mechanism for HpuAB. Strains with both receptors or only hmbR were present at similar frequencies among meningococcal disease isolates as compared with carriage isolates. However, >90 % of isolates from the three CCs CC5, CC8 and CC11 with the highest disease to carriage ratios contained both receptors. Strains with an hpuAB-only phenotype were under-represented among disease isolates, suggesting selection against this receptor during systemic disease, possibly due to the receptor having a high level of immunogenicity or being inefficient in acquisition of iron during systemic spread. Absence of hpuAB resulted from either complete deletion or replacement by an insertion element. In an examination of PV status, one or both receptors were found in an ON state in 91 % of disease and 71 % of carriage isolates. We suggest that expression of a haemoglobin receptor, either HmbR or HpuAB, is of major importance for systemic spread of meningococci, and that the presence of both receptors contributes to virulence in some strains

Macromolecular crowding links ribosomal protein gene dosage to growth rate in Vibrio cholerae

In fast-growing bacteria, the genomic location of ribosomal protein (RP) genes is biased towards the replication origin (oriC). This trait allows optimizing their expression during exponential phase since oriC neighboring regions are in higher dose due to multifork replication. Relocation of s10-spc-α locus (S10), which codes for most of the RP, to ectopic genomic positions shows that its relative distance to the oriC correlates to a reduction on its dosage, its expression, and bacterial growth rate. However, a mechanism linking S10 dosage to cell physiology has still not been determined.We hypothesized that S10 dosage perturbations impact protein synthesis capacity. Strikingly, we observed that in Vibrio cholerae, protein production capacity was independent of S10 position. Deep sequencing revealed that S10 relocation altered chromosomal replication dynamics and genome-wide transcription. Such changes increased as a function of oriC-S10 distance. Since RP constitutes a large proportion of cell mass, lower S10 dosage could lead to changes in macromolecular crowding, impacting cell physiology. Accordingly, cytoplasm fluidity was higher in mutants where S10 is most distant from oriC. In hyperosmotic conditions, when crowding differences are minimized, the growth rate and replication dynamics were highly alleviated in these strains.The genomic location of RP genes ensures its optimal dosage. However, besides of its essential function in translation, their genomic position sustains an optimal macromolecular crowding essential for maximizing growth. Hence, this could be another mechanism coordinating DNA replication to bacterial growth.Fil: Soler Bistue, Alfonso J. C.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Aguilar Pierlé, Sebastián. Institut Pasteur; FranciaFil: Garcia Garcerá, Marc. Institut Pasteur; FranciaFil: Val, Marie Eve. Institut Pasteur; FranciaFil: Sismeiro, Odile. Institut Pasteur; FranciaFil: Varet, Hugo. Institut Pasteur; FranciaFil: Sieira, Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Krin, Evelyne. Institut Pasteur; FranciaFil: Skovgaard, Ole. Roskilde Universitet; DinamarcaFil: Comerci, Diego José. Universidad Nacional de San Martin. Instituto de Investigaciones Biotecnologicas. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Investigaciones Biotecnologicas.; ArgentinaFil: Rocha, Eduardo P. C.. Institut Pasteur; FranciaFil: Mazel, Didier. Institut Pasteur; Franci