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In order to understand the effects of the earliest fluid‐assisted hydration processes on asteroids, we performed one hydrothermal experiment using three different reactants (FeO‐rich amorphous silicates, iron metal powder, and water) at conditions informed by our current state of knowledge of asteroidal alteration. This experiment provides, for the first time, clear evidence that the growth of fayalite can occur during hydrothermal alteration, as described previously in meteorites. These newly formed fayalite crystals are elongated and porous, similar to the ones described in CV3, CK, and ordinary chondrites. The results show that (1) fayalite could form even if chemical equilibrium was not reached in the experiment, at a water to rock mass ratio (0.4 W/R at the beginning of the experiment) higher than the values calculated to be thermodynamically viable at equilibrium (W/R > 0.2); (2) the composition and the texture of the reactants changed during the hydrothermal alteration process, suggesting that the reactants, especially the amorphous silicates, underwent dissolution and reprecipitation; (3) fayalite can form at low temperature (220 °C), which is at the transition between hydrothermal alteration and fluid‐assisted metamorphism in chondrites. The results are consistent with previous mineralogical observations and thermodynamic models, which suggest that fayalite crystals are formed on asteroidal parent bodies by the interaction between a hydrothermal fluid and disequilibrium assemblages that compose the pristine materials that condensed in the early solar nebula. This experiment suggests that two variables play a very important role in the formation of fayalite during the hydrothermal growth (W/R mass ratio and the fluid composition). These results are similar to the recent observations of the fine‐grained matrix of ordinary chondrites. [ABSTRACT FROM AUTHOR]

Introduction: Water ice forms in the interstellar clouds along with preexisting silicate grains forming amorphous structures that sublimate and re-condense with temperature changes, developing the precursors to protoplanetary disks [1]. Throughout the formation process, planetesimals inside the snowline tend to outgas any H2O that may have been trapped in the silicate grains. This leads to a depletion of H2O in terrestrial planets. However, the simplicity ends there because planets forming in regions where adsorbed H2O has been lost, but absorbed water is still locked into the silicate grains, can still contain a significant amount of water. In fact, analysis of basaltic magma shows that H2O content was at least 3 wt.% H2O or higher [2]. Knowing the temperatures at which adsorbed, and absorbed, H2O leaves silicate grains is crucial in understanding planetary formation, transfer of H2O across the solar system, sequestration of gases, and habitability, amongst others. Laboratory experiments can better constrain the temperatures at which H2O remains incorporated in planetary formation. Methods: Amorphous Mg-silicate smokes, similarly synthesized in procedures by Nuth, et al. 2002 [3], was used for this study. These were chosen because the formation for the smokes are indicative of high-temperature processes in the circumstellar outflows. The amorphous Mg-silicate samples were powdered and placed in the sample holder of a AABSPEC #2000-A multimode system. The cell was pumped under vacuum to pressures of 9.3e-6 bar and initial spectral measurements were taken at 300 K. Subsequent measurements were taken in 50K increments up to 1000K. Each measurement consisted of 1000 scans with a resolution of 4 cm-1 to ensure high resolution data. Spectra was collected using a Mattson RS-10000 Fourier Transform InfraRed (FTIR) spectrometer operating in the near and mid-IR regimes (2 m - 17 m). The data for each sample was normalized and plotted to demonstrate the change in features with increasing temperature. Results: The preliminary results of this investigation indicate that the solid state H2O contained within the smokes is removed from the sample between 725 and 750K. Initial spectra of the Mg-silicate smoke sample before it was heated up clearly displayed the 3µm and 4.4µm water bands. The bands are broad and relatively smooth, indicating that they are solid-state absorption features. The characteristic 10µm silicate feature is also visible, although it is very weak compared to the intensity of the other bands. At 700K the spectra show the H2O still in the solid-state at around 3µm and 4.4µm. In the 750K measurement, H2O emission features replace the solid state features. Emission features that were present in the spectra taken at higher temperatures were diminished as the temperature increased, until they disappeared almost completely at 950K. After the sample was heated up to temperatures of 1000K and cooled back down to 300K, in 100K increments, the emission features returned, all while retaining the 10µm feature. Post-ramp spectra of the silicate smoke was collected after it had been cooled down to 300K. The spectra shows the water bands in the same position, but after being subjected to heat, the bands are now emission features, indicating that the H2O being measured is in the gas phase. The 10µm silicate feature remains and is more pronounced, suggesting that the chemical integrity of the sample remained intact over the course of the heating run. The solid-state H2O features did not return, indicating that the H2O in the samples had been removed completely. Conclusions & Future Work: Preliminary results from this study suggest that the samples started losing their solid-state H2O features between 725 and 750K. This suggests that planetesimals forming within the snow line could have a higher water content. The procedures outlined in this abstract will be repeated in order to clearly quantify the temperature at which water is released from the amorphous smokes. Further work will also involve kinetic studies to determine the activation energy of the H2O in order to determine exactly how much water can be released, and how long it would take to release it. [ABSTRACT FROM AUTHOR]

Objectives: Physician documentation plays a central role in the delivery of safe patient care. It describes a physician's clinical decision-making and supports essential communication between healthcare providers within the patient's circle of care. Good documentation can potentially also decrease a physician's medico-legal risk. This study provides examples of documentation issues attributed to physicians practicing emergency medicine as identified by peer experts in civil legal actions, regulatory authority complaints (College) and hospital complaints (collectively, medico-legal cases) in Canada., Methods: We conducted a descriptive study and content analysis of medico-legal cases involving emergency department physicians from a national repository at the Canadian Medical Protective Association. Cases with peer expert criticism of an emergency physician's documentation, which were closed between 2016 and 2020, and occurred in an emergency department were included in our analysis., Results: Of the 1628 cases involving emergency medicine, our inclusion criteria identified that absent or insufficiently detailed documentation was present in 24% of cases (391/1,628). A detailed review of 20% of the cases (79/391), selected randomly, found that documentation issues were most often associated with the assessment and investigation stage of care. This pertained to documenting details of the clinical examination, relevant medical history, diagnosis, and differential diagnosis., Conclusions: For physicians practicing emergency medicine, criticism of documentation was frequently observed in medico-legal cases. Based on the findings of this study and the expert criticism related to documentation, emergency medicine physicians may consider reflecting upon their documentation of the care provided to determine if their documentation provides a clear and accurate chronicle of the care and the rationale for their clinical decisions., (© 2023. The Author(s).)

Background: Medico-legal data show opportunities to improve safe medical care; little is published on the experience of physicians-in-training with medical malpractice. The purpose of this study was to examine closed civil legal cases involving physicians-in-training over time and provide novel insights on case and physicians characteristics., Methods: We conducted a retrospective descriptive study of closed civil legal cases at the Canadian Medical Protective Association (CMPA), a mutual medico-legal defence organization for more than 105 000 physicians, representing an estimated 95% of physicians in Canada. Eligible cases involved at least 1 physician-in-training and were closed between 1993 and 2017 (for time trends) or 2008 and 2017 (for descriptive analyses). We analyzed case rates over time using Poisson regression and the annualized change rate. Descriptive analyses addressed case duration, medico-legal outcome and patient harm. We explored physician specialties and practice characteristics in a subset of cases., Results: Over a 25-year period (1993-2017), 4921 physicians-in-training were named in 2951 closed civil legal cases, and case rates decreased significantly (β = -0.04, 95% confidence interval -0.05 to -0.03, where β was the 1-year difference in log case rates). The annualized change rate was -1.1% per year. Between 2008 and 2017, 1901 (4.1%) of 45 967 physicians-in-training were named in 1107 civil legal cases. Cases with physicians-in-training generally involved more severe patient harm than cases without physicians-in-training. In a subgroup with available information ( n = 951), surgical specialties were named most often ( n = 531, 55.8%)., Interpretation: The rate of civil legal cases involving physicians-in-training has diminished over time, but more recent cases featured severe patient harm and death. Efforts to promote patient safety may enhance medical care and reduce the frequency and severity of malpractice issues for physicians-in-training., Competing Interests: Competing interests: All authors except Taryn Taylor were employees of the Canadian Medical Protective Association (CMPA) during the preparation of this manuscript. No other competing interests were declared., (© 2022 CMA Impact Inc. or its licensors.)