X-ray Linear Dichroism in cubic compounds: the case of Cr3+ in MgAl2O4

The angular dependence (x-ray linear dichroism) of the Cr K pre-edge in MgAl2O4:Cr3+ spinel is measured by means of x-ray absorption near edge structure spectroscopy (XANES) and compared to calculations based on density functional theory (DFT) and ligand field multiplet theory (LFM). We also present an efficient method, based on symmetry considerations, to compute the dichroism of the cubic crystal starting from the dichroism of a single substitutional site. DFT shows that the electric dipole transitions do not contribute to the features visible in the pre-edge and provides a clear vision of the assignment of the 1s-->3d transitions. However, DFT is unable to reproduce quantitatively the angular dependence of the pre-edge, which is, on the other side, well reproduced by LFM calculations. The most relevant factors determining the dichroism of Cr K pre-edge are identified as the site distortion and 3d-3d electronic repulsion. From this combined DFT, LFM approach is concluded that when the pre-edge features are more intense than 4 % of the edge jump, pure quadrupole transitions cannot explain alone the origin of the pre-edge. Finally, the shape of the dichroic signal is more sensitive than the isotropic spectrum to the trigonal distortion of the substitutional site. This suggests the possibility to obtain quantitative information on site distortion from the x-ray linear dichroism by performing angular dependent measurements on single crystals

Stress and anxiety during pregnancy and length of gestation: a federated study using data from five Canadian and European birth cohorts.

While its etiology is not fully elucidated, preterm birth represents a major public health concern as it is the leading cause of child mortality and morbidity. Stress is one of the most common perinatal conditions and may increase the risk of preterm birth. In this paper we aimed to investigate the association of maternal perceived stress and anxiety with length of gestation. We used harmonized data from five birth cohorts from Canada, France, and Norway. A total of 5297 pregnancies of singletons were included in the analysis of perceived stress and gestational duration, and 55,775 pregnancies for anxiety. Federated analyses were performed through the DataSHIELD platform using Cox regression models within intervals of gestational age. The models were fit for each cohort separately, and the cohort-specific results were combined using random effects study-level meta-analysis. Moderate and high levels of perceived stress during pregnancy were associated with a shorter length of gestation in the very/moderately preterm interval [moderate: hazard ratio (HR) 1.92 (95%CI 0.83, 4.48); high: 2.04 (95%CI 0.77, 5.37)], albeit not statistically significant. No association was found for the other intervals. Anxiety was associated with gestational duration in the very/moderately preterm interval [1.66 (95%CI 1.32, 2.08)], and in the early term interval [1.15 (95%CI 1.08, 1.23)]. Our findings suggest that perceived stress and anxiety are associated with an increased risk of earlier birth, but only in the earliest gestational ages. We also found an association in the early term period for anxiety, but the result was only driven by the largest cohort, which collected information the latest in pregnancy. This raised a potential issue of reverse causality as anxiety later in pregnancy could be due to concerns about early signs of a possible preterm birth

Associations of Maternal Educational Level, Proximity to Green Space During Pregnancy, and Gestational Diabetes With Body Mass Index From Infancy to Early Adulthood:A Proof-of-Concept Federated Analysis in 18 Birth Cohorts

International sharing of cohort data for research is important and challenging. We explored the feasibility of multicohort federated analyses by examining associations between 3 pregnancy exposures (maternal education, exposure to green vegetation, and gestational diabetes) and offspring body mass index (BMI) from infancy to age 17 years. We used data from 18 cohorts (n = 206,180 mother-child pairs) from the EU Child Cohort Network and derived BMI at ages 0-1, 2-3, 4-7, 8-13, and 14-17 years. Associations were estimated using linear regression via 1-stage individual participant data meta-analysis using DataSHIELD. Associations between lower maternal education and higher child BMI emerged from age 4 and increased with age (difference in BMI z score comparing low with high education, at age 2-3 years = 0.03 (95% confidence interval (CI): 0.00, 0.05), at 4-7 years = 0.16 (95% CI: 0.14, 0.17), and at 8-13 years = 0.24 (95% CI: 0.22, 0.26)). Gestational diabetes was positively associated with BMI from age 8 years (BMI z score difference = 0.18, 95% CI: 0.12, 0.25) but not at younger ages; however, associations attenuated towards the null when restricted to cohorts that measured gestational diabetes via universal screening. Exposure to green vegetation was weakly associated with higher BMI up to age 1 year but not at older ages. Opportunities of cross-cohort federated analyses are discussed.</p

Associations of Maternal Educational Level, Proximity to Green Space During Pregnancy, and Gestational Diabetes With Body Mass Index From Infancy to Early Adulthood:A Proof-of-Concept Federated Analysis in 18 Birth Cohorts

International sharing of cohort data for research is important and challenging. We explored the feasibility of multicohort federated analyses by examining associations between 3 pregnancy exposures (maternal education, exposure to green vegetation, and gestational diabetes) and offspring body mass index (BMI) from infancy to age 17 years. We used data from 18 cohorts (n = 206,180 mother-child pairs) from the EU Child Cohort Network and derived BMI at ages 0-1, 2-3, 4-7, 8-13, and 14-17 years. Associations were estimated using linear regression via 1-stage individual participant data meta-analysis using DataSHIELD. Associations between lower maternal education and higher child BMI emerged from age 4 and increased with age (difference in BMI z score comparing low with high education, at age 2-3 years = 0.03 (95% confidence interval (CI): 0.00, 0.05), at 4-7 years = 0.16 (95% CI: 0.14, 0.17), and at 8-13 years = 0.24 (95% CI: 0.22, 0.26)). Gestational diabetes was positively associated with BMI from age 8 years (BMI z score difference = 0.18, 95% CI: 0.12, 0.25) but not at younger ages; however, associations attenuated towards the null when restricted to cohorts that measured gestational diabetes via universal screening. Exposure to green vegetation was weakly associated with higher BMI up to age 1 year but not at older ages. Opportunities of cross-cohort federated analyses are discussed.</p

Kenya in Motion 2000-2020

This edited volume offers a broad understanding and particular visions of Kenya in the first quarter of the twenty-first century. By bringing together rigorous yet accessible contributions, it shows how, since the 2002 transition, Kenya has been striving for change through economic modernisation and political liberalisation. The planned transformations are coming to fruition, even if the legacies of the past and political habits are slowing down the process. The various chapters take us from developmental capitalism to extreme poverty and enduring inequalities, from reforms on paper to mixed results in multiple sectors: decentralised governance, natural resources, land, and education. They also explore Kenya’s ancient and colonial history and the diversity of its population. Thus, the book helps understand contemporary political, religious and community cleavages, the asymmetries between towns and the countryside, between Nairobi and the coast, in a country open to the world, as much through trade and finance as through art networks.Cet ouvrage offre une saisie synthétique et des visions particulières du Kenya en ce premier quart du XXIe siècle. Il rassemble des contributions rigoureuses et accessibles pour montrer comment, depuis l’alternance de 2002, le Kenya s’efforce de changer par la modernisation économique et la libéralisation politique. Les transformations annoncées voient le jour, même si les legs du passé et les habitus politiques en ralentissent la marche. Les différents chapitres nous mènent du capitalisme développemental kényan à la grande pauvreté et aux inégalités vivaces, des réformes sur le papier aux mises en œuvre en demi-teinte dans de multiples secteurs : gouvernance décentralisée, ressources naturelles, foncier, éducation. L’histoire ancienne et coloniale, la diversité du peuplement au Kenya permettent de mieux comprendre les clivages politiques, religieux et communautaires, les asymétries entre villes et campagnes, entre Nairobi et la côte, dans un Kenya ouvert sur le monde, autant par le commerce et la finance que par les réseaux de l’art

Le Kenya en marche, 2000-2020

Cet ouvrage offre une saisie synthétique et des visions particulières du Kenya en ce premier quart du XXIe siècle. Il rassemble des contributions rigoureuses et accessibles pour montrer comment, depuis l’alternance de 2002, le Kenya s’efforce de changer par la modernisation économique et la libéralisation politique. Les transformations annoncées voient le jour, même si les legs du passé et les habitus politiques en ralentissent la marche. Les différents chapitres nous mènent du capitalisme développemental kényan à la grande pauvreté et aux inégalités vivaces, des réformes sur le papier aux mises en œuvre en demi-teinte dans de multiples secteurs : gouvernance décentralisée, ressources naturelles, foncier, éducation. L’histoire ancienne et coloniale, la diversité du peuplement au Kenya permettent de mieux comprendre les clivages politiques, religieux et communautaires, les asymétries entre villes et campagnes, entre Nairobi et la côte, dans un Kenya ouvert sur le monde, autant par le commerce et la finance que par les réseaux de l’art.This edited volume offers a broad understanding and particular visions of Kenya in the first quarter of the twenty-first century. By bringing together rigorous yet accessible contributions, it shows how, since the 2002 transition, Kenya has been striving for change through economic modernisation and political liberalisation. The planned transformations are coming to fruition, even if the legacies of the past and political habits are slowing down the process. The various chapters take us from developmental capitalism to extreme poverty and enduring inequalities, from reforms on paper to mixed results in multiple sectors: decentralised governance, natural resources, land, and education. They also explore Kenya’s ancient and colonial history and the diversity of its population. Thus, the book helps understand contemporary political, religious and community cleavages, the asymmetries between towns and the countryside, between Nairobi and the coast, in a country open to the world, as much through trade and finance as through art networks

Fiche de syntaxe sur la négation (Corneille, Nicomède, Acte II, 3, v. 691-727)

Garagnon Anne-Marie, Calas Frédéric. Fiche de syntaxe sur la négation (Corneille, Nicomède, Acte II, 3, v. 691-727). In: L'Information Grammaticale, N. 77, 1998. pp. 6-10

Le Signe et la lettre, textes réunis par Jacques Anis, André Eskénazi et Jean-François Jeandillou, en hommage à Michel Arrivé, Paris, L’Harmattan, collection «Sémantiques » , 2002

Calas Frédéric, Garagnon Anne-Marie. Le Signe et la lettre, textes réunis par Jacques Anis, André Eskénazi et Jean-François Jeandillou, en hommage à Michel Arrivé, Paris, L’Harmattan, collection «Sémantiques » , 2002. In: L'Information Grammaticale, N. 108, 2006. pp. 57-59

Esquisse de lecture syntaxique de Britannicus et Bérénice (parties du discours)

Garagnon Anne-Marie, Calas Frédéric. Esquisse de lecture syntaxique de Britannicus et Bérénice (parties du discours). In: L'Information Grammaticale, N. 68, 1996. pp. 16-24

Le Signe et la lettre, textes réunis par Jacques Anis, André Eskénazi et Jean-François Jeandillou, en hommage à Michel Arrivé, Paris, L’Harmattan, collection «Sémantiques » , 2002

Calas Frédéric, Garagnon Anne-Marie. Le Signe et la lettre, textes réunis par Jacques Anis, André Eskénazi et Jean-François Jeandillou, en hommage à Michel Arrivé, Paris, L’Harmattan, collection «Sémantiques » , 2002. In: L'Information Grammaticale, N. 108, 2006. pp. 57-59