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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]

OBJECTIVE: Emergency medicine is an evolving discipline in Canadian medical schools. Little has been published regarding student preferences for emergency medicine training during the clerkship phase of MD programs. We assessed medical students' perceptions of a newly developed emergency medicine clerkship rotation involving multiple learning modalities. The evaluation process included assessment of the rotation's instructional elements and overall educational value. METHODS: The first cohort of medical students to complete this new emergency medicine clerkship was invited to answer a questionnaire just before graduation. Students rated their preferences for components of the rotation using paired comparisons. Open ended questions explored students' satisfaction with the emergency medicine clerkship as well as perceptions of the rotation's impact on career development. RESULTS: Of the 94 students in the first clerkship cohort, 81 (86%) responded to the survey. Students found the emergency medicine clerkship highly valuable, citing the broad range of cases seen, close supervision, and opportunities to develop clinical assessment, decision making and procedural skills. Students' curricular preferences were for advanced cardiac life support (ACLS) (26.4%), clinical shifts (20.6%), supervised clinical shifts (17.8%), procedural skills laboratories (14.8%), tutorials (10.8%) and preceptor assisted learning sessions (9.8%). CONCLUSION: This new emergency medicine clerkship program incorporated multiple learning methods within a 4-week rotation and was highly rated by students. Although clinical shifts and ACLS were generally preferred activities, students had varying individual preferences for specific learning activities. Multiple learning methods allowed all students to benefit from the rotation. This study makes a compelling case for including an emergency medicine rotation with multiple learning modalities as a core element of clerkship at every medical school. [ABSTRACT FROM AUTHOR]

A mentor is a person who takes a special interest in the professional development of a junior colleague and provides guidance and support. Mentoring can be beneficial for students, residents, junior colleagues and researchers and can be very rewarding for the physician who provides this guidance. Although mentoring is a well recognized topic in academic medicine, relatively little has been written about mentoring in emergency medicine (EM). Consequently, we conducted a literature review on mentoring in EM and present our findings in this paper. We discuss different models of mentoring, factors that foster the development of strong mentor ship programs, the responsibilities of mentors and mentees, and issues specific to mentorship of female, minority and research physicians. We also present several case scenarios as a basis for recommendations for teachers and learners in EM. [ABSTRACT FROM AUTHOR]

BACKGROUND: The faculty development community has been challenged to more rigorously assess program impact and move beyond traditional outcomes of knowledge tests and self ratings. PURPOSE: The purpose was to (a) assess our ability to measure supervisors' feedback skills as demonstrated in a clinical setting and (b) compare the results with traditional outcome measures of faculty development interventions. METHODS: A pre-post study design was used. Resident and expert ratings of supervisors' demonstrated feedback skills were compared with traditional outcomes, including a knowledge test and participant self-evaluation. RESULTS: Pre-post knowledge increased significantly (pre = 61%, post = 85%; p < .001) as did participant's self-evaluation scores (pre = 4.13, post = 4.79; p < .001). Participants' self-evaluations were moderately to poorly correlated with resident (pre r = .20, post r = .08) and expert ratings (pre r = .43, post r = -.52). Residents and experts would need to evaluate 110 and 200 participants, respectively, to reach significance. CONCLUSIONS: It is possible to measure feedback skills in a clinical setting. Although traditional outcome measures show a significant effect, demonstrating change in teaching behaviors used in practice will require larger scale studies than typically undertaken currently. [ABSTRACT FROM AUTHOR]

Discusses the composition of chondritic meteorites with pre-solar diamonds and silicon carbide grains. Similarities of noble gases isotope composition; Systematic survey of meteorite types for pre-solar materials; Implications for meteoritics.

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.)

Context: Available literature exploring medical liability and postgraduate medical education consistently posits that postgraduate trainees worry about their exposure to medico-legal liability. This assumption has formed the basis for research and curriculum development., Objectives: The aim of this study was to describe the encounters that lead physicians-in-training to seek external medico-legal guidance. We sought to provide empirical evidence on trends and themes related to medico-legal advice requests from physicians-in-training., Methods: Our primary dataset consisted of records of calls from physicians-in-training to the medico-legal helpline of the Canadian Medical Protective Association (CMPA), a national mutual defence organisation providing medico-legal advice and liability protection for over 95% of Canada's physicians. We conducted a trend analysis of the frequency of calls for advice over 10 years from physician-in-training compared with non-trainee physicians. Furthermore, we performed a content analysis of calls made over the most recent 2 years (2016-2017) to elucidate the concerns that led to trainees seeking medico-legal advice., Results: The 10-year trend analysis revealed that the annual growth in the number of physician-in-training advice calls (8.8%) exceeded other CMPA physician groups and was in excess of trainee population growth over the same period. The content analysis identified four core themes: managing confidential information, complex care situations, academic matters and patient safety incidents., Conclusions: Our findings indicate that trainees are asking questions about their medico-legal liability with increasing frequency. This study contributes new evidence on the issues that lead to trainees seeking help. We believe that understanding trainees' medico-legal advice requests will support medical educators to tailor quality improvement education to learners' needs., (© 2020 John Wiley & Sons Ltd and The Association for the Study of Medical Education.)

Dust is found throughout the universe and plays an important role for a wide range of astrophysical phenomena. In recent years, new IR facilities have provided powerful new data for understanding these phenomena. However, interpretation of these data is often complicated by a lack of complementary information about the optical properties of astronomically relevant materials. The Optical Properties of Astronomical Silicates with Infrared Techniques (OPASI-T) program at NASA's Goddard Space Flight Center is designed to provide new high-quality laboratory data from which we can derive the optical properties of astrophysical dust analogues. This program makes use of multiple instruments, including new equipment designed and built specifically for this purpose. The suite of instruments allows us to derive optical properties over a wide wavelength range, from the near-IR through the millimeter, also providing the capability for exploring how these properties depend upon the temperature of the sample. In this paper, we discuss the overall structure of the research program, describe the new instruments that have been developed to meet the science goals, and demonstrate the efficacy of these tools., (© 2011 Optical Society of America)

Understanding dynamic conditions in the Solar Nebula is the key to prediction of the material to be found in comets. We suggest that a dynamic, large-scale circulation pattern brings processed dust and gas from the inner nebula back out into the region of cometesimal formation-extending possibly hundreds of astronomical units (AU) from the sun-and that the composition of comets is determined by a chemical reaction network closely coupled to the dynamic transport of dust and gas in the system. This scenario is supported by laboratory studies of Mg silicates and the astronomical data for comets and for protoplanetary disks associated with young stars, which demonstrate that annealing of nebular silicates must occur in conjunction with a large-scale circulation. Mass recycling of dust should have a significant effect on the chemical kinetics of the outer nebula by introducing reduced, gas-phase species produced in the higher temperature and pressure environment of the inner nebula, along with freshly processed grains with "clean" catalytic surfaces to the region of cometesimal formation. Because comets probably form throughout the lifetime of the Solar Nebula and processed (crystalline) grains are not immediately available for incorporation into the first generation of comets, an increasing fraction of dust incorporated into a growing comet should be crystalline olivine and this fraction can serve as a crude chronometer of the relative ages of comets. The formation and evolution of key organic and biogenic molecules in comets are potentially of great consequence to astrobiology.

The timescale for the accretion of bodies in the disk surrounding a young star depends upon a number of assumptions, but there are few observational constraints. In our own Solar System, measurements of meteoritic components can provide information about the inner regions of the nebula, but not the outer parts. Observations of the evolution of more massive protostellar systems (Herbig Ae/Be stars) imply that significant changes occur in the physical properties of their dust with time. The simplest explanation is that thermal annealing of the original, amorphous grains in the hot inner nebula slowly increases the fractional abundance of crystalline material over time. Crystalline dust is then transported outward, where it is incorporated into comets that serve as a long-term reservoir for dust disks, such as that surrounding Beta Pictoris. Here we show that when applied to our own Solar System, this process can explain observed variations in both the volatile and dusty components of comets, while also providing a natural indicator of a comet's mean formation age. Studies of comets with different dust contents can therefore be used to investigate the timescales of the early Solar System.