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A fully automated isotopic profile deconvoluted chromatogram (IPDC) algorithm (Fakouri Baygi et al. in Anal Chem 91:15509–15517, 2019) and user interactive HaloSeeker 1.0 (Léon et al. in Anal Chem 91:3500–3507, 2019) were compared to test the efficacy of these two computationally enhanced non-targeted screening (CENTS) tools in isolating unknown Br/Cl compounds using high-resolution mass spectrometry (HRMS) data. HaloSeeker depends on a user to monitor the performance of the peak picking algorithm and assign molecular formulas for each isotopic signature in an ergonomic interface. Alternatively, the IPDC algorithm automatically assigns and ranks candidate molecular formulas within a set of search criteria. Both CENTS tools were evaluated using fish and sediment data acquired at 22,000 (mHRMS) and > 100,000 (uHRMS) mass resolutions, respectively. The IPDC algorithm detected 85% of compounds detected by HaloSeeker as the first candidate compound in the sediment sample, with fewer false positives. In the sediment data, the IPDC algorithm detected several compounds such as clofoctol and chlorinated paraffins that were not reported using HaloSeeker 1.0. Upon further inspection, these compounds were isolated by the HaloSeeker program, but not reported by the user. HaloSeeker detected all significant and insignificant chemical ionization products (relative to IPDC), but additional false positives were isolated in the mHRMS polychlorinated biphenyl reference standard and trout sample. HaloSeeker detected 62% of the legacy contaminant features isolated by the IPDC algorithm in the fish data (mHRMS). The comparison of these two CENTS tools demonstrates that matrix complexity and mass resolution of the HRMS platform are the key factors when choosing automated and user interactive CENTS tools. [ABSTRACT FROM AUTHOR]

Background: As aerospace cast parts move to more complex geometries, the impact of process variabilities must be evaluated more precisely to provide new, less empirical acceptation criteria. However, experimental lifetime assessment with Thermal Gradient Mechanical Fatigue (TGMF) are still complicated to reproduce in a laboratory environment. Objective: This paper investigates the impact of geometrical variability on thermo-mechanical fatigue life of Nickel-based superalloy single crystal parts. Methods: To this end, hollow specimens with cooling holes drilled in their centre have been produced with parametrized variations of the wall thickness and have been characterized by X-ray tomography. An experimental fatigue setup operating at 1100 ∘ C, with a thermal gradient of 50 ∘ C across the wall, has been developed to assess the life of each specimen. Results: Experimental lifetime assessment were conducted on a sample of specimens containing geometrical defects. Optical observations during the tests have permitted to study crack initiation and propagation in the vicinity of the cooling hole, an area of high thermal and stress gradients where damage localize. Axial strains (in the loading direction) were also gathered and compared to prove the impact of process variabilities on mechanical behaviour. Conclusions: Significant mechanical differences are observed during the tests which can related to the geometrical variations of the specimens and their interaction with the shaped hole. Tests results will be further used to calibrate a creep-fatigue model for lifetime predictions. [ABSTRACT FROM AUTHOR]

Brominated flame retardants (BFR) are primarily used as flame retardant additives in insulating materials. These lipophilic compounds can bioaccumulate in animal tissues, leading to human exposure via food ingestion. Although their concentration in food is not yet regulated, several of these products are recognised as persistent organic pollutants; they are thought to act as endocrine disruptors. The present study aimed to characterise the occurrence of two families of BFRs (hexabromocyclododecane (HBCDD) and polybrominated diphenyl ethers (PBDE)) in hen eggs and broiler or pig meat in relation to their rearing environments. Epidemiological studies were carried out on 60 hen egg farms (34 without an open-air range, 26 free-range), 57 broiler farms (27 without an open-air range, 30 free-range) and 42 pig farms without an open-air range in France from 2013 to 2015. For each farm, composite samples from either 12 eggs, five broiler pectoral muscles or three pig tenderloins were obtained. Eight PBDE congeners and three HBCDD stereoisomers were quantified in product fat using gas chromatography–high-resolution mass spectrometry, or high-performance liquid chromatography–tandem mass spectrometry, respectively. The frequencies of PBDE detection were 28% for eggs (median concentration 0.278 ng/g fat), 72% for broiler muscle (0.392 ng/g fat) and 49% for pig muscle (0.403 ng/g fat). At least one HBCDD stereoisomer was detected in 17% of eggs (0.526 ng/g fat), 46% of broiler muscle (0.799 ng/g fat) and 36% of pig muscle (0.616 ng/g fat). Results were similar in concentration to those obtained in French surveillance surveys from 2012 to 2016. Nevertheless, the contamination of free-range eggs and broilers was found to be more frequent than that of conventional ones, suggesting that access to an open-air range could be an additional source of exposure to BFRs for animals. However, the concentration of BFRs in all products remained generally very low. No direct relationship could be established between the occurrence of BFRs in eggs and meat and the characteristics of farm buildings (age, building materials). The potential presence of BFRs in insulating materials is not likely to constitute a significant source of animal exposure as long as the animals do not have direct access to these materials. [ABSTRACT FROM AUTHOR]

We report on unusual low temperature (175 °C) heteroepitaxial growth of germanium thin films using a standard radio-frequency plasma process. Spectroscopic ellipsometry and transmission electron microscopy (TEM) reveal a perfect crystalline quality of epitaxial germanium layers on (100) c-Ge wafers. In addition direct germanium crystal growth is achieved on (100) c-Si, despite 4.2% lattice mismatch. Defects rising from Ge/Si interface are mostly located within the first tens of nanometers, and threading dislocation density (TDD) values as low as 106 cm-2 are obtained. Misfit stress is released fast: residual strain of -0.4% is calculated from Moiré pattern analysis. Moreover we demonstrate a striking feature of low temperature plasma epitaxy, namely the fact that crystalline quality improveswith thicknesswithout epitaxy breakdown, as shown by TEM and depth profiling of surface TDD. [ABSTRACT FROM AUTHOR]

Background: The current standard initial therapies for deep venous thrombosis are low-molecular-weight heparin and unfractionated heparin. In a dose-ranging study of patients with symptomatic deep venous thrombosis, fondaparinux had efficacy and a safety profile similar to those of low-molecular-weight heparin (dalteparin).Objective: To evaluate whether fondaparinux has efficacy and safety similar to those of enoxaparin in patients with deep venous thrombosis.Design: Randomized, double-blind study.Setting: 154 centers worldwide.Patients: 2205 patients with acute symptomatic deep venous thrombosis.Intervention: Fondaparinux, 7.5 mg (5.0 mg in patients weighing <50 kg and 10.0 mg in patients weighing >100 kg) subcutaneously once daily, or enoxaparin, 1 mg/kg of body weight, subcutaneously twice daily for at least 5 days and until vitamin K antagonists induced an international normalized ratio greater than 2.0.Measurements: The primary efficacy outcome was the 3-month incidence of symptomatic recurrent venous thromboembolic complications. The main safety outcomes were major bleeding during initial treatment and death. An independent, blinded committee adjudicated all outcomes.Results: 43 (3.9%) of 1098 patients randomly assigned to fondaparinux had recurrent thromboembolic events compared with 45 (4.1%) of 1107 patients randomly assigned to enoxaparin (absolute difference, -0.15 percentage point [95% CI, -1.8 to 1.5 percentage points]). Major bleeding occurred in 1.1% of patients receiving fondaparinux and 1.2% of patients receiving enoxaparin. Mortality rates were 3.8% and 3.0%, respectively.Limitations: Follow-up was incomplete in 0.4% of fondaparinux-treated patients and 1.0% of enoxaparin-treated patients.Conclusions: Once-daily subcutaneous fondaparinux was at least as effective (not inferior) and safe as twice-daily, body weight-adjusted enoxaparin in the initial treatment of patients with symptomatic deep venous thrombosis. [ABSTRACT FROM AUTHOR]

Objective: Fondaparinux sodium is the first in a new class of synthetic factor Xa inhibitors that binds reversibly with high affinity to antithrombin III. It has been investigated for the prevention and treatment of arterial and venous thrombotic disorders and approved for use at a dose of 2.5mg once daily in the prevention of venous thromboembolism in major orthopaedic surgery. The pharmacokinetics of fondaparinux sodium were determined in eight studies in young and elderly healthy volunteers. Results: After a 2.5mg subcutaneous dose to young volunteers, absolute bioavailability was 100% and absorption was rapid and complete [peak plasma concentration (C) 0.34 mg/L occurred at approximately 2 hours]. Within- and total-subject variability estimates were small: 5.5 and 11.6%, respectively, for Cand 4.4 and 17.5% for area under the concentration-time curve (AUC). Steady state was obtained after the third or fourth once-daily dose, with a 1.3-fold increase in C and AUC. Distribution volume (7 to 11L) was limited to blood volume. There was no evidence of metabolism. Fondaparinux sodium was almost completely excreted in urine as unchanged compound (64 to 77% of the dose was recovered at 72 hours after administration). Plasma clearance was 5.1 to 7.9 ml/min, renal clearance 4.0 to 7.9 ml/min, and the terminal half-life was 17 hours in young volunteers and 21 hours in elderly volunteers. Pharmacokinetics of fondaparinux sodium were linear in the range 2 to 8mg subcutaneously and 2 to 20mg intravenously. Pharmacokinetics observed in healthy elderly volunteers were consistent with findings in young male volunteers. Conclusion: The favourable pharmacokinetic profile of fondaparinux sodium is likely to play an important role in the major advance that the drug represents in the prevention and treatment of thrombotic disorders. [ABSTRACT FROM AUTHOR]