82 research outputs found

    Abnormal CO2 and H2O Diffusion in CALF-20(Zn) Metal-Organic Framework Angstropores

    Full text link
    Carbon mitigation is one challenging issue that the world is facing. To tackle deleterious impacts of CO2, processes emerged, including chemisorption from amine based solvents, and more recently physisorption in porous solids. While CO2 capture from amine is more mature, this process is corrosive and detrimental for environment. Physisorption in Metal-Organic Frameworks (MOFs) is currently attracting a considerable attention, however the selection of the optimum sorbent is still challenging. While CO2 adsorption by MOFs have been widely explored from a thermodynamics standpoint, dynamical aspects remain less explored. CALF-20(Zn) MOF was recently proposed as a promising alternative to the commercially used CO2 13X zeolite sorbents, however, in-depth understanding of microscopic mechanisms originating its good performance still have to be achieved. In this report, we deliver a microscopic insight of CO2 and H2O in CALF-20(Zn) by atomistic simulations. CALF-20(Zn) revealed to exhibit unconventional guest-host behaviors that give rise to abnormal thermodynamic and diffusion. The hydrophobic nature of the solid leads to a low water adsorption enthalpy at low loading followed by a gradual increase, driven by strong water hydrogen bonds, found to arrange as quasi 1D water wires in MOF porosity, recalling water behavior in carbon nanotubes and aquaporins. While no super-diffusion found, this behavior was shown to impact diffusion along with guests loading, with a minimum correlated with inflection point of adsorption isotherm corresponding to wires formation. Interestingly, diffusion of both CO2 and H2O were also found to be of the same order of magnitude with similar non-linear behaviors.Comment: 15 pages, 8 figure

    Human pregnancy complicated by Chlamydia psittaci acquired from goat, a new zaonotic infection ?

    Get PDF
    Nous rapportons le cas d’une femme dont la grossesse s’est spontané ment interrompue à 32 semaines d’aménorrhée en raison d’une infection très sévère par Chlamydia psittaci. Cette infection est secondaire à un contact avec un troupeau de chèvres. Neuf cas d’infection materno-fœtale par Chlamydia psittaci d’origine animale sont décrits dans la littérature, il s’agit toujours d’une contamination par les brebis atteintes de chlamydiose abortive. La chèvre peut également être infectée par ce germe, mais la trans mission à la femme enceinte de la chlamydiose abortive caprine n’a pas été décrit jusqu’à présent.A case of chlamydial infection in pregnant woman is described. This infection was contracted from goat. The woman, who had contact with caprine abortion, spontaneously delivered a stillborn infant in the 32nd week of pregnancy. She developed dessiminated intravascular coagulation post partum with acute renal failure and pulmonary oedema. Nine cases of chlamydial infections in pregnant women have been reported in literature, in all cases, the infection was contracted from ewes suffering from enzootic abortion. Such an infection acquired from goat have not been previously described

    Maternal Blood Lead Levels and the Risk of Pregnancy-Induced Hypertension: The EDEN Cohort Study

    Get PDF
    International audienceBACKGROUND: Prior studies revealed associations of environmental lead exposure with risks of hypertension and elevated blood pressure. OBJECTIVE: We examined the effect of blood lead levels on blood pressure and the incidence of pregnancy-induced hypertension (PIH) in the second and third trimesters of pregnancy. METHODS: One thousand seventeen pregnant women were enrolled in two French municipalities between 2003 and 2005 for the EDEN (Etude des Déterminants pré et post natals du développement et de la santé de l' Enfant) cohort study. Blood lead concentrations were measured by atomic absorption spectrometry in mothers between 24 and 28 weeks of gestation. RESULTS: PIH was diagnosed in 106 subjects (10.9%). Age, parity, weight gain, alcohol, smoking habits, and calcium supplementation were comparable between hypertensive and nonhypertensive women. Lead levels were significantly higher in PIH cases (mean +/- SD, 2.2 +/- 1.4 mug/dL) than in normotensive patients (1.9 +/- 1.2 mug/dL; p = 0.02). Adjustment for potential confounder effects slightly attenuated but did not eliminate the significant association between blood lead levels and the risk of PIH (adjusted odds ratio of PIH = 3.3; 95% confidence interval, 1.1-9.7). We also observed geographic differences in lead exposure and in the incidence of PIH and found significant correlations between blood lead levels and unadjusted as well as adjusted systolic and diastolic blood pressures after 24 weeks of gestation. CONCLUSIONS: These findings confirm the relationship between blood lead levels at mid-pregnancy and blood pressure and suggest that environmental lead exposure may play an etiologic role in PIH

    Maternal Personal Exposure to Airborne Benzene and Intrauterine Growth

    Get PDF
    International audienceBACKGROUND: Studies relying on outdoor pollutants measures have reported associations between air pollutants and birth weight. OBJECTIVE: Our aim was to assess the relation between maternal personal exposure to airborne benzene during pregnancy and fetal growth. METHODS: We recruited pregnant women in two French maternity hospitals in 2005-2006 as part of the EDEN mother-child cohort. A subsample of 271 nonsmoking women carried a diffusive air sampler for a week during the 27th gestational week, allowing assessment of benzene exposure. We estimated head circumference of the offspring by ultrasound measurements during the second and third trimesters of pregnancy and at birth. RESULTS: Median benzene exposure was 1.8 microg/m(3) (5th, 95th percentiles, 0.5, 7.5 microg/m(3)). Log-transformed benzene exposure was associated with a gestational age-adjusted decrease of 68 g in mean birth weight [95% confidence interval (CI), -135 to -1 g] and of 1.9 mm in mean head circumference at birth (95% CI, -3.8 to 0.0 mm). It was associated with an adjusted decrease of 1.9 mm in head circumference assessed during the third trimester (95% CI, -4.0 to 0.3 mm) and of 1.5 mm in head circumference assessed at the end of the second trimester of pregnancy (95% CI, -3.1 to 0 mm). CONCLUSIONS: Our prospective study among pregnant women is one of the first to rely on personal monitoring of exposure; a limitation is that exposure was assessed during 1 week only. Maternal benzene exposure was associated with decreases in birth weight and head circumference during pregnancy and at birth. This association could be attributable to benzene and a mixture of associated traffic-related air pollutants

    Low-dose hydrocortisone reduces norepinephrine duration in severe burn patients: a randomized clinical trial

    Get PDF
    INTRODUCTION: The aim of this study was to assess the effect of low-dose corticosteroid therapy in reducing shock duration after severe burn. METHODS: A placebo-controlled, double-blind, randomized clinical trial (RCT) was performed on two parallel groups in the burn intensive care unit (ICU). Patients were randomized to receive either low-dose corticosteroid therapy or placebo for seven days. A corticotropin test was performed at the time of randomization, before the administration of the treatment dose. Thirty-two severely burned patients with refractory shock (>0.5 μg/kg/min of norepinephrine) were prospectively included in the study. RESULTS: We included 12 patients in the hydrocortisone-treated group and 15 patients in the placebo group in the final analysis. Among these patients, 21 were nonresponders to the corticotropin test. Median norepinephrine treatment duration (primary objective) was significantly lower in the corticosteroid-treated versus the placebo group (57 hours versus 120 hours, P = 0.035). The number of patients without norepinephrine 72 hours after inclusion was significantly lower in the treated group (P = 0.003, log-rank test analysis). The total quantities of norepinephrine administered to patients were lower in the hydrocortisone-treated versus the placebo group (1,205 μg/kg (1,079 to 2,167) versus 1,971 μg/kg (1,535 to 3,893), P = 0.067). There was no difference in terms of ICU or hospital length of stay, sepsis incidence, cicatrization or mortality. CONCLUSIONS: In this placebo-controlled, randomized, double-blind clinical trial, we show for the first time that the administration of low-dose hydrocortisone in burn patients with severe shock reduces vasopressor administration. TRIAL REGISTRATION: Clinicaltrial.gov NCT00149123. Registered 6 September 2005. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13054-015-0740-0) contains supplementary material, which is available to authorized users

    Brain classification reveals the right cerebellum as the best biomarker of dyslexia

    Get PDF
    Background Developmental dyslexia is a specific cognitive disorder in reading acquisition that has genetic and neurological origins. Despite histological evidence for brain differences in dyslexia, we recently demonstrated that in large cohort of subjects, no differences between control and dyslexic readers can be found at the macroscopic level (MRI voxel), because of large variances in brain local volumes. In the present study, we aimed at finding brain areas that most discriminate dyslexic from control normal readers despite the large variance across subjects. After segmenting brain grey matter, normalizing brain size and shape and modulating the voxels' content, normal readers' brains were used to build a 'typical' brain via bootstrapped confidence intervals. Each dyslexic reader's brain was then classified independently at each voxel as being within or outside the normal range. We used this simple strategy to build a brain map showing regional percentages of differences between groups. The significance of this map was then assessed using a randomization technique. Results The right cerebellar declive and the right lentiform nucleus were the two areas that significantly differed the most between groups with 100% of the dyslexic subjects (N = 38) falling outside of the control group (N = 39) 95% confidence interval boundaries. The clinical relevance of this result was assessed by inquiring cognitive brain-based differences among dyslexic brain subgroups in comparison to normal readers' performances. The strongest difference between dyslexic subgroups was observed between subjects with lower cerebellar declive (LCD) grey matter volumes than controls and subjects with higher cerebellar declive (HCD) grey matter volumes than controls. Dyslexic subjects with LCD volumes performed worse than subjects with HCD volumes in phonologically and lexicon related tasks. Furthermore, cerebellar and lentiform grey matter volumes interacted in dyslexic subjects, so that lower and higher lentiform grey matter volumes compared to controls differently modulated the phonological and lexical performances. Best performances (observed in controls) corresponded to an optimal value of grey matter and they dropped for higher or lower volumes. Conclusion These results provide evidence for the existence of various subtypes of dyslexia characterized by different brain phenotypes. In addition, behavioural analyses suggest that these brain phenotypes relate to different deficits of automatization of language-based processes such as grapheme/phoneme correspondence and/or rapid access to lexicon entries. article available here: http://www.biomedcentral.com/1471-2202/10/6

    The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

    Get PDF
    Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age  6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score  652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

    Utilisation des tests de concordance de scripts pour l’évaluation en informatique

    No full text
    Student assessment must not only take into account their acquired knowledge but also their skills. To improve the assessment of their professional skills in computer science, we have chosen to adapt the concepts of Script Concordance Tests (SCT) to the scientific domain. In this paper, we describe how we adapted SCT to computer science. We propose some SCT and an experiment. The experiment has shown advantages and drawbacks of SCTs, that allows to think of a wider use of SCT in other disciplines.L’évaluation des étudiants doit porter non seulement sur les connaissances qu’ils ont acquises, mais également sur les compétences qu’ils ont développées. C’est pour améliorer l’évaluation du savoir-faire de nos élèves en informatique que nous avons choisi d’adapter le principe des tests de concordance de scripts (TCS) à ce domaine. Les TCS ont pour objectif d’évaluer le raisonnement d’étudiants placés dans une situation professionnelle. Nous avons défini un nouveau champ d’application pour les TCS, nous avons conçu des TCS et nous les avons expérimentés. Cette expérience nous a permis d’établir les forces et les limites des TCS en informatique, une analyse qui ouvre la porte à un usage plus large de ce dispositif dans d’autres disciplines.Magnin Morgan, Moreau Guillaume. Utilisation des tests de concordance de scripts pour l’évaluation en informatique. In: Sciences et Technologies de l'Information et de la Communication pour l'Éducation et la Formation, volume 18, 2011. TICE. pp. 263-286
    corecore