Polarization and relaxation of radon

Investigations of the polarization and relaxation of $^{209}$Rn by spin exchange with laser optically pumped rubidium are reported. On the order of one million atoms per shot were collected in coated and uncoated glass cells. Gamma-ray anisotropies were measured as a signal of the alignment (second order moment of the polarization) resulting from the combination of polarization and quadrupole relaxation at the cell walls. The temperature dependence over the range 130$^\circ$C to 220$^\circ$C shows the anisotropies increasing with increasing temperature as the ratio of the spin exchange polarization rate to the wall relaxation rate increases faster than the rubidium polarization decreases. Polarization relaxation rates for coated and uncoated cells are presented. In addition, improved limits on the multipole mixing ratios of some of the main gamma-ray transitions have been extracted. These results are promising for electric dipole moment measurements of octupole-deformed $^{223}$Rn and other isotopes, provided sufficient quantities of the rare isotopes can be produced.Comment: 4 pages, 4 figure

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Anisotropic intergranular damage development and fracture in a 14Cr ferritic ODS steel under high-temperature tension and creep

International audienceThis work addresses damage mechanisms at high temperature of a hot extruded 14Cr oxide dispersion strengthened steel rod, in particular, anisotropy induced by its strong morphological and crystallographic texture. Under uniaxial tension, intergranular damage and unstable fracture increased with test temperature; they appeared much easier along the rod axis than perpendicular to it. Creep fracture of smooth specimens involved crack initiation from the side surfaces and intergranular crack propagation, accompanied by intergranular damage. In order to get rid of fracture surface oxidation by the air environment, a methodology promoting crack nucleation from inside the specimen was built. From tensile and creep tests on notched specimens the fracture initiation location and fracture stability were first mapped as a function of test temperature, maximal stress triaxiality and loading direction. Then, for the first time to the authors' knowledge, interrupted tests on notched tensile and creep specimens, followed by low-temperature fracture allowed revealing fracture surfaces formed at high temperature, but unconnected to the external environment. Intergranular fracture and grain boundary grooving were evidenced there, together with strong chemical reactivity at the surface of internal cavities during damage development at high temperature

Estimation of physical performance and measurements of habitual physical activity may capture men with high risk to fall-Data from the Mr Os Sweden cohort

To evaluate if clinically usable estimates of physical performance and level of habitual physical activity are associated with fall risk in elderly men. A population-based sample of 3014 randomly selected men aged 69-80 years was recruited to medical centers in Gothenburg, Malmoe, or Uppsala. The level of physical activity and self-reported falls during the preceding 12 months was evaluated using a questionnaire. The physical performance ability was estimated by measurements of handgrip strength, a timed stands test, a 6-m walking test and a 20-cm narrow walk test. Falls were reported in 16.5% of the men. Fallers performed 6.2 ± 19.0% (mean ± standard deviations; S.D.) less in right handgrip measures, 8.8 ± 40.6% slower in the timed stands test, 6.8 ± 30.8% slower in the 6-m walking test, and 5.3 ± 28.8% slower in the 20-cm narrow walk test (all p < 0.001, respectively). The odds ratio for falls among men who performed <-3 S.D. or failed compared to the mean (+1 S.D. to -1 S.D.) in the timed stands test was 3.41 (95% CI 2.31-5.02; p < 0.001) and 2.46 (95% CI 1.80-3.34; p < 0.001) in 20-cm narrow walk test. There were more fallers that never were physical active (73.0% vs. 65.4%, p < 0.001) and who were sitting more (6.4 ± 2.5 h/day vs. 6.0 ± 2.3 h/day, p < 0.05) than among the non-fallers. Fallers scored less than non-fallers in all the estimates of physical performance and they were more sedentary in their life style. The report suggests that clinical usable tests of physical performance and evaluation of habitual physical activity in the clinical situation possibly can be used to predict risk of falls in elderly men

Thermokinetic Modelling of High-Temperature Evolution of Primary Nb(C,N) in Austenite Applied to Recrystallization of 316Nb Austenitic Stainless Steel

International audienceThe size evolution of niobium carbonitrides Nb(C,N) and the evolution of the composition of an austenitic matrix in 316Nb stainless steel were simulated using DICTRA software. For the first time, the complete nine-element composition of steel was taken into account during isothermal and even anisothermal heat treatments. A reduced model was then proposed to optimize the calculation time for complex heat treatments. The change in the mean Nb content in austenite due to Nb(C,N) evolution during different heat treatments was studied. It qualitatively agrees with experimental data as obtained by electron probe microanalysis. Furthermore, the model was successfully applied to explain the effect of heat treatments on the recrystallization behavior of 316Nb steel during hot torsion tests. Moreover, the effect of the thermodynamic database and the number of alloying elements chosen was discussed. We showed that taking into account seven or even nine elements greatly improves the accuracy compared to usual simplified compositions. The proposed method can be useful in designing heat treatments promoting or conversely hindering recrystallization for a wide variety of Nb-bearing steels

Differential response to donepezil in MRI subtypes of mild cognitive impairment

Abstract Background Donepezil is an approved therapy for the treatment of Alzheimer’s disease (AD). Results across clinical trials have been inconsistent, which may be explained by design-methodological issues, the pathophysiological heterogeneity of AD, and diversity of included study participants. We investigated whether response to donepezil differs in mild cognitive impaired (MCI) individuals demonstrating different magnetic resonance imaging (MRI) subtypes. Methods From the Hippocampus Study double-blind, randomized clinical trial, we included 173 MCI individuals (donepezil = 83; placebo = 90) with structural MRI data, at baseline and at clinical follow-up assessments (6–12-month). Efficacy outcomes were the annualized percentage change (APC) in hippocampal, ventricular, and total grey matter volumes, as well as in the AD cortical thickness signature. Participants were classified into MRI subtypes as typical AD, limbic-predominant, hippocampal-sparing, or minimal atrophy at baseline. We primarily applied a subtyping approach based on continuous scale of two subtyping dimensions. We also used the conventional categorical subtyping approach for comparison. Results Donepezil-treated MCI individuals showed slower atrophy rates compared to the placebo group, but only if they belonged to the minimal atrophy or hippocampal-sparing subtypes. Importantly, only the continuous subtyping approach, but not the conventional categorical approach, captured this differential response. Conclusions Our data suggest that individuals with MCI, with hippocampal-sparing or minimal atrophy subtype, may have improved benefit from donepezil, as compared with MCI individuals with typical or limbic-predominant patterns of atrophy. The newly proposed continuous subtyping approach may have advantages compared to the conventional categorical approach. Future research is warranted to demonstrate the potential of subtype stratification for disease prognosis and response to treatment. Trial registration ClinicalTrial.gov NCT00403520. Submission Date: November 21, 2006

Polarization and relaxation of ^209Rn

The study of the nuclear polarization of radon is motivated by the expected large enhancement of sensitivity to a CP-violating electric dipole moment (EDM) in isotopes with octupole deformation or vibrational strength. In preparation for EDM measurements, the polarization of radon by spin exchange with laser-polarized alkali metals is studied. The measurement of the alignment of 209Rn using HPGe detectors to observe the resulting anisotropy in the 337 and 745 keV gamma rays emitted following electron-capture decay of 209Rn to 209At is demonstrated. Radon is polarized via spin-exchange collisions with rubidium atoms in an uncoated Pyrex optical pumping cell. Anisotropy measurements at several temperatures are used to study polarization and relaxation

Low-dose IL-2 in children with recently diagnosed type 1 diabetes: a Phase I/II randomised, double-blind, placebo-controlled, dose-finding study

International audienceAims/hypothesis: Low-dose IL-2 (ld-IL2) selectively activates and expands regulatory T cells (Tregs) and thus has the potential to skew the regulatory/effector T (Treg/Teff) cell balance towards improved regulation. We investigated which low doses of IL-2 would more effectively and safely activate Tregs during a 1 year treatment in children with recently diagnosed type 1 diabetes.Methods: Dose Finding Study of IL-2 at Ultra-low Dose in Children With Recently Diagnosed Type 1 Diabetes (DF-IL2-Child) was a multicentre, double-blinded, placebo-controlled, dose-finding Phase I/II clinical trial conducted in four centres at university hospitals in France: 24 children (7-14 years old) with type 1 diabetes diagnosed within the previous 3 months were randomly assigned 1:1:1:1 to treatment by a centralised randomisation system, leading to a 7/5/6/6 patient distribution of placebo or IL-2 at doses of 0.125, 0.250 or 0.500 million international units (MIU)/m2, given daily for a 5 day course and then fortnightly for 1 year. A study number was attributed to patients by an investigator unaware of the randomisation list and all participants as well as investigators and staff involved in the study conduct and analyses were blinded to treatments. The primary outcome was change in Tregs, expressed as a percentage of CD4+ T cells at day 5. It pre-specified that a ≥60% increase in Tregs from baseline would identify Treg high responders. Results: There were no serious adverse events. Non-serious adverse events (NSAEs) were transient and mild to moderate. In treated patients vs placebo, the commonest NSAE was injection site reaction (37.9% vs 3.4%), whereas other NSAEs were at the same level (23.3% vs 19.2%). ld-IL2 induced a dose-dependent increase in the mean proportion of Tregs, from 23.9% (95% CI -11.8, 59.6) at the lowest to 77.2% (44.7, 109.8) at the highest dose, which was significantly different from placebo for all dose groups. However, the individual Treg responses to IL-2 were variable and fluctuated over time. Seven patients, all among those treated with the 0.250 and 0.500 MIU m-2 day-1 doses, were Treg high responders. At baseline, they had lower Treg proportions in CD4+ cells than Treg low responders, and serum soluble IL-2 receptor α (sIL-2RA) and vascular endothelial growth factor receptor 2 (VEGFR2) levels predicted the Treg response after the 5 day course. There was no significant change in glycaemic control in any of the dose groups compared with placebo. However, there was an improved maintenance of induced C-peptide production at 1 year in the seven Treg high responders as compared with low responders.Conclusions/interpretation: The safety profile at all doses, the dose-dependent effects on Tregs and the observed variability of the Treg response to ld-IL2 in children with newly diagnosed type 1 diabetes call for use of the highest dose in future developments. The better preservation of insulin production in Treg high responders supports the potential of Tregs in regulating autoimmunity in type 1 diabetes, and warrants pursuing the investigation of ld-IL2 for its treatment and prevention