Reactive transport modelling of a low-pH concrete / clay interface

Versión aceptada de https://doi.org/10.1016/j.apgeochem.2020.104562[Abstract:] Cement-based materials are key components in the barrier system and structural support of repositories for disposal of nuclear waste. As such, increased understanding of their long-term performance under repository conditions is paramount for the safety assessment. Quantification of the impact that cement-based materials could have on the surrounding barriers and the host rock is essential to assess long-term safety of the repository system. This interaction can impact the physical properties of the system near the interface and needs to be assessed by means of numerical modelling. A reactive transport modelling study of the interaction between a newly-developed low-pH concrete and a clay host rock (i.e. Callovo Oxfordian) over 100,000 years is presented here. The main goal is to build confidence in the consistency of the different modelling approaches and in the application of different reactive transport codes (iCP, ORCHESTRA, OpenGeosys-GEM, CORE2D, and MIN3P) to analyse the performance of the recently developed low-pH concrete within the CEBAMA project. A common setup of a reference case was established, including precipitation/dissolution reactions, redox and cation exchange processes, building upon preliminary cases of increasing complexity. In addition, a set of sensitivity cases was simulated to test the effect of key geochemical and transport parameters on the results, including the impact of porosity changes on the diffusion coefficient and electrochemical couplings. Different reactive transport codes were used in the benchmark. Overall, the results show not only the high level of understanding of the governing processes but also the good agreement obtained with different codes, which is essential to demonstrate the applicability of reactive transport modelling to support safety assessment. The sensitivity and preliminary cases modelled show that the results obtained are much more sensitive to changes to transport parameters and couplings than to the different modelling tools used in each case. In addition, the impact of including or not the slow kinetics of dissolution of the claystone minerals is shown to be negligible in the studied scenarios.The research leading to these results has received funding from the European Union's European Atomic Energy Community's Horizon 2020 Programme (NFRP-2014/2015) under grant agreement, 662147 – CEBAMA. V. Montoya., J. Poonoosamy and G. Deissmann acknowledge the German Federal Ministry of Education and Research (Grant 02NUK053A) and the Initiative and Networking Fund of the Helmholtz Association (Grant SO-093) within the iCross project for partial funding. The authors would like to thank Barbara Lothenbach for fruitful discussions on modelling cement hydration of the low-pH cement system and the two reviewers for constructive and valuable comments that have helped to improve the manuscript.Alemania. German Federal Ministry of Education and Research; 02NUK053AAlemania. Initiative and Networking Fund of the Helmholtz Association; SO-09

Structural and functional characterization of the Mycobacterium tuberculosis uridine monophosphate kinase: insights into the allosteric regulation†

Nucleoside Monophosphate Kinases (NMPKs) family are key enzymes in nucleotide metabolism. Bacterial UMPKs depart from the main superfamily of NMPKs. Having no eukaryotic counterparts they represent attractive therapeutic targets. They are regulated by GTP and UTP, while showing different mechanisms in Gram(+), Gram(–) and archaeal bacteria. In this work, we have characterized the mycobacterial UMPK (UMPKmt) combining enzymatic and structural investigations with site-directed mutagenesis. UMPKmt exhibits cooperativity toward ATP and an allosteric regulation by GTP and UTP. The crystal structure of the complex of UMPKmt with GTP solved at 2.5 Å, was merely identical to the modelled apo-form, in agreement with SAXS experiments. Only a small stretch of residues was affected upon nucleotide binding, pointing out the role of macromolecular dynamics rather than major structural changes in the allosteric regulation of bacterial UMPKs. We further probe allosteric regulation by site-directed mutagenesis. In particular, a key residue involved in the allosteric regulation of this enzyme was identified

MR Imaging of Adverse Effects and Ocular Growth Decline after Selective Intra-Arterial Chemotherapy for Retinoblastoma

This retrospective multicenter study examines therapy-induced orbital and ocular MRI findings in retinoblastoma patients following selective intra-arterial chemotherapy (SIAC) and quantifies the impact of SIAC on ocular and optic nerve growth. Patients were selected based on medical chart review, with inclusion criteria requiring the availability of posttreatment MR imaging encompassing T2-weighted and T1-weighted images (pre- and post-intravenous gadolinium administration). Qualitative features and quantitative measurements were independently scored by experienced radiologists, with deep learning segmentation aiding total eye volume assessment. Eyes were categorized into three groups: eyes receiving SIAC (Rb-SIAC), eyes treated with other eye-saving methods (Rb-control), and healthy eyes. The most prevalent adverse effects post-SIAC were inflammatory and vascular features, with therapy-induced contrast enhancement observed in the intraorbital optic nerve segment in 6% of patients. Quantitative analysis revealed significant growth arrest in Rb-SIAC eyes, particularly when treatment commenced ≤ 12 months of age. Optic nerve atrophy was a significant complication in Rb-SIAC eyes. In conclusion, this study highlights the vascular and inflammatory adverse effects observed post-SIAC in retinoblastoma patients and demonstrates a negative impact on eye and optic nerve growth, particularly in children treated ≤ 12 months of age, providing crucial insights for clinical management and future research

Leber Congenital Amaurosis: Comprehensive Survey of the Genetic Heterogeneity, Refinement of the Clinical Definition, and Genotype-Phenotype Correlations as a Strategy for Molecular Diagnosis

Communicated by Jean-Claude Kaplan Leber congenital amaurosis (LCA) is the earliest and most severe form of all inherited retinal dystrophies, responsible for congenital blindness. Disease-associated mutations have been hitherto reported in seven genes. These genes are all expressed preferentially in the photoreceptor cells or the retinal pigment epithelium but they are involved in strikingly different physiologic pathways resulting in an unforeseeable physiopathologic variety. This wide genetic and physiologic heterogeneity that could largely increase in the coming years, hinders the molecular diagnosis in LCA patients. The genotyping is, however, required to establish genetically defined subgroups of patients ready for therapy. Here, we report a comprehensive mutational analysis of the all known genes in 179 unrelated LCA patients, including 52 familial and 127 sporadic (27/127 consanguineous) cases. Mutations were identified in 47.5% patients. GUCY2D appeared to account for most LCA cases of our series (21.2%), followed by CRB1 (10%), RPE65 (6.1%), RPGRIP1 (4.5%), AIPL1 (3.4%), TULP1 (1.7%), and CRX (0.6%). The clinical history of all patients with mutations was carefully revisited to search for phenotype variations. Sound genotype-phenotype correlations were found that allowed us to divide patients into two main groups. The first one includes patients whose symptoms fit the traditional definition of LCA, i.e., congenital or very early cone-rod dystrophy, while the second group gathers patients affected with severe yet progressive rodcone dystrophy. Besides, objective ophthalmologic data allowed us to subdivide each group into two subtypes. Based on these findings, we have drawn decisional flowcharts directing the molecular analysis of LCA genes in a given case. These flowcharts will hopefully lighten the heavy task of genotyping new patients but only if one has access to the most precise clinical history since birth

Gendered Pathways? : The Impact of Over-Education on Wage Trajectories Among Immigrant Men and Women in the UK

A growing body of research has examined over-education as a mechanism of post-employment inequality between immigrants and natives in host-country labor markets. Despite the growing share of high-skilled female migrants globally and their persistent disadvantages in labor market outcomes, male immigrants have been the focus of this literature. Addressing this gap, this study utilizes longitudinal data from the UK survey “Understanding Society” to examine the impact of over-education on native-immigrant wage disparities in the UK, and its intersection with gender. Through descriptive analysis, the study reveals persistent inequalities in over- education experiences among immigrant men, and in particular Western immigrant women. Growth curve modelling is used to estimate initial and long-term wage-effects over-education among immigrant men and women, finding that over-educated immigrant women face substantial initial wage penalties, albeit not statistically significant, but demonstrate a wage- recovery over time. Conversely, over-educated immigrant men face smaller initial wage penalties, but display significantly lower wage growth than their correctly matched counterparts. In conclusion, these disparities underscore the gendered constraints and opportunities shaping immigrants’ assimilation paths; while the wages of correctly matched immigrant men gradually converge with those of natives over time, correctly matched immigrant women face persistent wage disadvantages and limited upward mobility.

Är Sverige på väg mot en dubbel arbetsmarknad? : En kvantitativ studie om flexibilitet i arbetsmarknaden och arbetsmässiga konsekvenser av atypiska anställningar.

Hårdnande konkurrens i en globaliserad och teknologidriven arbetsmarknad föranleder ökade krav på flexibla affärsmodeller för allt fler arbetsgivare. Atypisk arbetskraft används som en reserv för att möta marknadens fluktuerande behov och som en buffert för fast anställda vilket förklaras ge upphov till ojämlika arbetsförhållanden och segmentering av arbetskraften i ”insiders” och ”outsiders”. Denna studie ämnar bidra till att fylla den kunskapslucka som finns avseende flexibilisering i den svenska arbetsmarknaden genom att studera skillnader i arbetstillfredsställelse mellan fast och atypiskt anställda och därtill den medierande effekten av lön och arbetsotrygghet. Studien utgår från Dual Labor Market Theory vilken dikotomiserar arbetsmarknaden i ett primärt och sekundärt segment med starka institutionella barriärer emellan. Arne Kallebergs teori om arbetsbelöningar utgör utgångspunkt för studiens teoretisering och operationalisering av arbetstillfredsställelse. Datamaterialet baseras på den sjätte europeiska undersökningen om arbetsvillkor, EWCS6, 2015. Analysen utgår från totalt 807 anställda män och kvinnor mellan 18–65 år som vid datainsamlingstillfället var folkbokförda i Sverige. Med bivariata analyser visas att atypiskt anställda har lägre lön och upplever en högre arbetsotrygghet än fast anställda. Genom enkel och multipel regressionsanalys visas att atypisk anställning är negativt associerat med arbetstillfredsställelse och att lön medierar det negativa sambandet. Resultaten går i linje med tidigare forskning som visat negativ inverkan av atypisk anställning på arbetstillfredsställelse och lön samt ger stöd åt Dual Labor Market Theory genom att påvisa strukturella komponenters betydelse i sammanhanget. Otrygghet i arbetet visas ha svag inverkan på arbetstillfredsställelse och obefintlig medierande effekt på sambandet mellan atypisk anställning och arbetstillfredsställelse vilket strider mot tidigare forskningsresultat och diskuteras med hänsyn till det ekonomiska skyddsnät som innefattas i svensk socialpolitik däribland A-kassa, socialbidrag och statligt finansierade basutgifter

Är Sverige på väg mot en dubbel arbetsmarknad? : En kvantitativ studie om flexibilitet i arbetsmarknaden och arbetsmässiga konsekvenser av atypiska anställningar.

Hårdnande konkurrens i en globaliserad och teknologidriven arbetsmarknad föranleder ökade krav på flexibla affärsmodeller för allt fler arbetsgivare. Atypisk arbetskraft används som en reserv för att möta marknadens fluktuerande behov och som en buffert för fast anställda vilket förklaras ge upphov till ojämlika arbetsförhållanden och segmentering av arbetskraften i ”insiders” och ”outsiders”. Denna studie ämnar bidra till att fylla den kunskapslucka som finns avseende flexibilisering i den svenska arbetsmarknaden genom att studera skillnader i arbetstillfredsställelse mellan fast och atypiskt anställda och därtill den medierande effekten av lön och arbetsotrygghet. Studien utgår från Dual Labor Market Theory vilken dikotomiserar arbetsmarknaden i ett primärt och sekundärt segment med starka institutionella barriärer emellan. Arne Kallebergs teori om arbetsbelöningar utgör utgångspunkt för studiens teoretisering och operationalisering av arbetstillfredsställelse. Datamaterialet baseras på den sjätte europeiska undersökningen om arbetsvillkor, EWCS6, 2015. Analysen utgår från totalt 807 anställda män och kvinnor mellan 18–65 år som vid datainsamlingstillfället var folkbokförda i Sverige. Med bivariata analyser visas att atypiskt anställda har lägre lön och upplever en högre arbetsotrygghet än fast anställda. Genom enkel och multipel regressionsanalys visas att atypisk anställning är negativt associerat med arbetstillfredsställelse och att lön medierar det negativa sambandet. Resultaten går i linje med tidigare forskning som visat negativ inverkan av atypisk anställning på arbetstillfredsställelse och lön samt ger stöd åt Dual Labor Market Theory genom att påvisa strukturella komponenters betydelse i sammanhanget. Otrygghet i arbetet visas ha svag inverkan på arbetstillfredsställelse och obefintlig medierande effekt på sambandet mellan atypisk anställning och arbetstillfredsställelse vilket strider mot tidigare forskningsresultat och diskuteras med hänsyn till det ekonomiska skyddsnät som innefattas i svensk socialpolitik däribland A-kassa, socialbidrag och statligt finansierade basutgifter

IMPACT DE LA POLLUTION ATMOSPHERIQUE URBAINE SUR L'ALTERATION DE VERRES MODELES DE FAIBLE DURABILITE

L'ETUDE DE FRAGMENTS DE VITRAUX DE LA SAINTE CHAPELLE MONTRE L'ALTERATION MORPHOLOGIQUE ET CHIMIQUE DU SUBSTRAT ET LA PRESENCE DE CROUTES SUPERFICIELLES. LA SURFACE EST GRANULEUSE, FRACTUREE, AVEC DES CRATERES. LA COMPOSITION CHIMIQUE MONTRE UNE PERTE EN POTASSIUM, UN ENRICHISSEMENT EN PLOMB. LES CROUTES SONT SURTOUT GYPSEUSES. ELLES PEUVENT ETRE CALCITIQUES OU HYPER-PLOMBIFERES. ELLES CONTIENNENT DES PARTICULES EXOGENES. DEUX VERRES MODELES DE FAIBLE DURABILITE ONT ETE EXPOSES AU SOMMET DE LA TOUR ST JACQUES. UNE SERIE DE VERRES A ETE EXPOSEE A PARTIR DE NOV. 1997, UNE AUTRE A PARTIR DE MAI 1998. LA MOITIE DES VERRES A ETE EXPOSEE A LA PLUIE, L'AUTRE A L'ABRI DE LA PLUIE. UN SUIVI DES PARAMETRES ATMOSPHERIQUES ET UNE ETUDE PONCTUELLE DE L'AEROSOL PARTICULAIRE ONT ETE MENES EN PARALLELE. QUELS QUE SOIENT LA PERIODE, LE MODE OU LA DUREE DE L'EXPOSITION, LA COMPOSITION CHIMIQUE DES DEUX VERRES SE MODIFIE AVEC LA FORMATION D'UNE COUCHE HYDRATEE ET APPAUVRIE EN CATIONS MODIFICATEURS. LA COMPOSITION DE CETTE COUCHE EVOLUE AVEC LA DUREE DE L'EXPOSITION. SA FORMATION EST ACCELEREE DANS LE CAS DES VERRES EXPOSES A LA PLUIE. LES VERRES EXPOSES A LA PLUIE PRESENTENT DES MICROFRACTURES. DES PARTICULES D'ORIGINE ATMOSPHERIQUE SE DEPOSENT SUR LA SURFACE QUEL QUE SOIT LE MODE D'EXPOSITION. LA SURFACE DES VERRES ABRITES SE RECOUVRE PEU A PEU DE NEOCRISTALLISATIONS. LA MORPHOLOGIE, LA COMPOSITION CHIMIQUE ET LA MINERALOGIE DES NEOCRISTALLISATIONS EST CARACTERISTIQUE DU VERRE SOUS-JACENT. LES SELS SULFATES SONT MAJORITAIRES. DES NITRATES ET DES CARBONATES SONT EGALEMENT OBSERVES. LEUR QUANTITE ET LEUR COMPOSITION EVOLUENT AVEC LA DUREE D'EXPOSITION. LA FORMATION DES SULFATES DEPEND DES TENEURS EN SO 2 ET DE LA TEMPERATURE MAIS EST INDEPENDANTE DES TENEURS EN SOUFRE PARTICULAIRE OU DE LA COMPOSITION DU VERRE. LA NATURE DU VERRE INFLUENCE LA QUANTITE DE NITRATES FORMEE. LA TEMPERATURE PEUT EN FAVORISER LA FORMATION ALORS QUE LES TENEURS EN OXYDES D'AZOTE NE SEMBLENT PAS INTERVENIR.PARIS12-CRETEIL BU Multidisc. (940282102) / SudocSudocFranceF

Irradiation stéréotaxique robotisée au Cyberknife des tumeurs primitives pulmonaires T1 T2 N0 inopérables (expérience préliminaire du CHU de Tours)

TOURS-BU Médecine (372612103) / SudocSudocFranceF

L'aromathérapie (conseils à l'officine et fiches pratiques)

MONTPELLIER-BU Pharmacie (341722105) / SudocSudocFranceF