Effect of Plasma Temperature on Major Element Prediction Accuracy From Laser‐Induced Breakdown Spectroscopy

Laser-induced breakdown spectra (LIBS) were collected on a diverse suite of ∼2,600 geological standards using four laser energies (2.4–7.2 mJ) to assess how variations in irradiance from stand-off distance affect prediction accuracy. Mismatches in laser energies and plasma temperatures between training and prediction datasets introduce substantial uncertainty in major element predictions. For example, using 2.4 mJ spectra to predict 7.2 mJ data results in errors of ±8.9, ±1.4, ±3.8, ±3.2, ±1.6, ±1.0, ±0.6, and ±1.0 wt% for SiO2, TiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, and K2O, respectively. When plasma temperatures of unknowns are represented in a multiple-plasma-temperature training set, prediction accuracies improve for the same oxides: ±3.0, ±0.3, ±1.3, ±1.4, ±1.0, ±0.7, ±0.5, and ±0.5 wt%. These results suggest that accuracies reported for Mars LIBS predictions based on single-distance, single laser-power calibration data may be overly optimistic except where Mars plasmas serendipitously match those acquired in the laboratory

Temperature dependence and recoil-free fraction effects in olivines across the Mg-Fe solid solution.

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The effect of gamma irradiation on the structural properties of olivine

Gamma irradiation studies of (Mg0.905Fe0.095)2SiO4 olivine were performed using X-ray fluorescence method, X-ray diffraction, Raman and Mössbauer spectroscopy. The absorbed doses were 300, 600 and 1000 Gy. Small irradiation doses cause an increase of lattice vibrations and small deformation of both M1 and M2 octahedron. The observed effect is similar to the results expose to high temperature. However, the small deformation takes place only in unit cell of Olivine’s structure

Barriers and Facilitators to Implementation of Antibiotic Stewardship Programmes in Hospitals in Developed Countries: Insights From Transnational Studies

Objectives: To identify perceived influences on implementation of antibiotic stewardship programmes (ASPs) in hospitals, across healthcare systems, and to exemplify the use of a behavioral framework to conceptualize those influences. Methods: EMBASE and MEDLINE databases were searched from 01/2001 to 07/2017 and reference lists were screened for transnational studies that reported barriers and/or facilitators to implementing actual or hypothetical ASPs or ASP-supporting strategies. Extracted data were synthesized using content analysis with the Theoretical Domains Framework as an organizing framework. Commonly reported influences were quantified. Results: From 3,196 abstracts 75 full-text articles were screened for inclusion. Eight studies met the eligibility criteria. The number of countries involved in each study ranged from 2 to 36. These studies included a total of 1849 participants. North America, Europe and Australasia had the strongest representation. Participants were members of special interest groups, designated hospital representatives or clinical experts. Ten of the 14 theoretical domains in the framework were present in the results reported in the included studies. The most commonly reported (≥4 out of 8 studies) influences on ASP implementation were coded in the domain “environmental context and resources” (e.g., problems with data and information systems; lack of key personnel; inadequate financial resources) and “goals” (other higher priorities). Conclusions: Despite an extensive transnational research effort, there is evidence from international studies of substantial barriers to implementing ASPs in hospitals, even in developed countries. Large-scale efforts to implement hospital antibiotic stewardship in those countries will need to overcome issues around inadequacy of information systems, unavailability of key personnel and funding, and the competition from other priority initiatives. We have enhanced the evidence base to inform guidance by taking a behavioral approach to identify influences on ASP uptake. Systematic review registration: PROSPERO registration number CRD42017076425

Isolated Absent Aortic Valve: A Unique Fetal Case With Echocardiographic, Pathologic, and Genetic Correlation

We present a 22-week fetus with isolated absent aortic valve and inverse circular shunt. The pregnancy was interrupted. Here, echocardiography and pathology images demonstrate this rare entity. Whole genome sequencing revealed a potentially disease-causing variant in the APC gene. Whole genome sequencing should be considered in severe and rare fetal diseases. (Level of Difficulty: Advanced.