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Some active asteroids have been proposed to be the result of impact events. Because active asteroids are generally discovered serendipitously only after their tail formation, the process of the impact ejecta evolving into a tail has never been directly observed. NASA's Double Asteroid Redirection Test (DART) mission, apart from having successfully changed the orbital period of Dimorphos, demonstrated the activation process of an asteroid from an impact under precisely known impact conditions. Here we report the observations of the DART impact ejecta with the Hubble Space Telescope (HST) from impact time T+15 minutes to T+18.5 days at spatial resolutions of ~2.1 km per pixel. Our observations reveal a complex evolution of ejecta, which is first dominated by the gravitational interaction between the Didymos binary system and the ejected dust and later by solar radiation pressure. The lowest-speed ejecta dispersed via a sustained tail that displayed a consistent morphology with previously observed asteroid tails thought to be produced by impact. The ejecta evolution following DART's controlled impact experiment thus provides a framework for understanding the fundamental mechanisms acting on asteroids disrupted by natural impact., accepted by Nature

Statler et al., NASA’s Double Asteroid Redirection Test (DART) is the first full-scale test of an asteroid deflection technology. Results from the hypervelocity kinetic impact and Earth-based observations, coupled with LICIACube and the later Hera mission, will result in measurement of the momentum transfer efficiency accurate to ∼10% and characterization of the Didymos binary system. But DART is a single experiment; how could these results be used in a future planetary defense necessity involving a different asteroid? We examine what aspects of Dimorphos’s response to kinetic impact will be constrained by DART results; how these constraints will help refine knowledge of the physical properties of asteroidal materials and predictive power of impact simulations; what information about a potential Earth impactor could be acquired before a deflection effort; and how design of a deflection mission should be informed by this understanding. We generalize the momentum enhancement factor β, showing that a particular direction-specific β will be directly determined by the DART results, and that a related direction-specific β is a figure of merit for a kinetic impact mission. The DART β determination constrains the ejecta momentum vector, which, with hydrodynamic simulations, constrains the physical properties of Dimorphos’s near-surface. In a hypothetical planetary defense exigency, extrapolating these constraints to a newly discovered asteroid will require Earth-based observations and benefit from in situ reconnaissance. We show representative predictions for momentum transfer based on different levels of reconnaissance and discuss strategic targeting to optimize the deflection and reduce the risk of a counterproductive deflection in the wrong direction., This work was supported in part by the DART mission, NASA contract No. 80MSFC20D0004 to JHU/APL. Some of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). S.C. acknowledges funding through the Crosby Fellowship of the Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology. E.D., S.I., A.L., M.P., A.R., and P.T. are grateful to the Italian Space Agency (ASI) for financial support through agreement No. 2019-31-HH.0 in the context of ASI’s LICIACube mission, and agreement No. 2022-8-HH.0 for ESA’s Hera mission. R.L. appreciates the funding from the European Union’s Horizon 2020 research and innovation program, grant agreement No. 870377 (project NEO-MAPP). P.M. acknowledges funding support from the French space agency CNES, ESA and the European Union’s Horizon 2020 research and innovation program under grant agreement No. 870377 (project NEO-MAPP). R.M. acknowledges support from a NASA Space Technology Graduate Research Opportunities (NSTGRO) Award (80NSSC22K1173). R.N. acknowledges support from NASA/FINESST (NNH20ZDA001N). J.O. and I.H. were supported by the Spanish State Research Agency (AEI) project No. MDM-2017-0737 Unidad de Excelencia “María de Maeztu”—Centro de Astrobiología (CSIC-INTA). They are also grateful for all logistical support provided by Instituto Nacional de Técnica Aeroespacial (INTA). S.R.S. acknowledges support from the DART Participating Scientist Program, grant No. 80NSSC22K0318. J.M.T.R. was funded by FEDER/Ministerio de Ciencia e Innovación—Agencia Estatal de Investigación of Spain (grant No. PGC2018-097374-B-I00).

The association between the physio-pathological variables of type 2 diabetes (T2D) and gut microbiota composition suggests a new avenue to track the disease and improve the outcomes of pharmacological and non-pharmacological treatments. This enterprise requires new strategies to elucidate the metabolic disturbances occurring in the gut microbiome as the disease progresses. To this end, physiological knowledge and systems biology pave the way for characterizing microbiota and identifying strategies in a move toward healthy compositions. Here, we dissect the recent associations between gut microbiota and T2D. In addition, we discuss recent advances in how drugs, diet, and exercise modulate the microbiome to favor healthy stages. Finally, we present computational approaches for disentangling the metabolic activity underlying host-microbiota codependence. Altogether, we envision that the combination of physiology and computational modeling of microbiota metabolism will drive us to optimize the diagnosis and treatment of T2D patients in a personalized way.

IntroductionThe human gut microbiota (GM) is a dynamic system which ecological interactions among the community members affect the host metabolism. Understanding the principles that rule the bidirectional communication between GM and its host, is one of the most valuable enterprise for uncovering how bacterial ecology influences the clinical variables in the host.MethodsHere, we used SparCC to infer association networks in 16S rRNA gene amplicon data from the GM of a cohort of Mexican patients with type 2 diabetes (T2D) in different stages: NG (normoglycemic), IFG (impaired fasting glucose), IGT (impaired glucose tolerance), IFG + IGT (impaired fasting glucose plus impaired glucose tolerance), T2D and T2D treated (T2D with a 5-year ongoing treatment).ResultsBy exploring the network topology from the different stages of T2D, we observed that, as the disease progress, the networks lose the association between bacteria. It suggests that the microbial community becomes highly sensitive to perturbations in individuals with T2D. With the purpose to identify those genera that guide this transition, we computationally found keystone taxa (driver nodes) and core genera for a Mexican T2D cohort. Altogether, we suggest a set of genera driving the progress of the T2D in a Mexican cohort, among them Ruminococcaceae NK4A214 group, Ruminococcaceae UCG-010, Ruminococcaceae UCG-002, Ruminococcaceae UCG-005, Alistipes, Anaerostipes, and Terrisporobacter.DiscussionBased on a network approach, this study suggests a set of genera that can serve as a potential biomarker to distinguish the distinct degree of advances in T2D for a Mexican cohort of patients. Beyond limiting our conclusion to one population, we present a computational pipeline to link ecological networks and clinical stages in T2D, and desirable aim to advance in the field of precision medicine.

Single-cell transcriptomics (scRNA-seq) is becoming a technology that is transforming biological discovery in many fields of medicine. Despite its impact in many areas, scRNASeq is technologically and experimentally limited by the inefficient transcript capture and the high rise of noise sources. For that reason, imputation methods were designed to denoise and recover missing values. Many imputation methods (e.g., neighbor averaging or graph diffusion) rely on k nearest neighbor graph construction derived from a mathematical space as a low-dimensional manifold. Nevertheless, the construction of mathematical spaces could be misleading the representation of densities of the distinct cell phenotypes due to the negative effects of the curse of dimensionality. In this work, we demonstrated that the imputation of data through diffusion approach on PCA space favor over-smoothing when increases the dimension of PCA and the diffusion parameters, such k-NN (k-nearest neighbors) and t (value of the exponentiation of the Markov matrix) parameters. In this case, the diffusion on PCA space distorts the cell neighborhood captured in the Markovian matrix creating an artifact by connecting densities of distinct cell phenotypes, even though these are not related phenotypically. In this situation, over-smoothing of data is due to the fact of shared information among spurious cell neighbors. Therefore, it can not account for more information on the variability (from principal components) or nearest neighbors for a well construction of a cell-neighborhood. To solve above mentioned issues, we propose a new approach called sc-PHENIX( single cell-PHEnotype recovery by Non-linear Imputation of gene eXpression) which uses PCA-UMAP initialization for revealing new insights into the recovered gene expression that are masked by diffusion on PCA space. sc-PHENIX is an open free algorithm whose code and some examples are shown at https://github.com/resendislab/sc-PHENIX.

Oblique, low-velocity impacts onto extraterrestrial terrain are an inevitable occurrence during space exploration. We conduct two-dimensional discrete simulations to model such impacts into a bed of triangular grains. Finite element method provides the basis for simulation, enabling the angular grain geometry. Our findings re-create the three classes of impact behavior previously noted from experiments: full-stop, rollout, and ricochet \citep*{Wright2020}. An application of Set Voronoi tessellation assesses packing fraction at a high resolution, revealing how grains shift relative to each other during an impact event. Calculation of Von Mises strain distributions then reveal how grains shift relative to the overall system, leading to the notion of the 'skin zone'. Intuition would suggest that the region of perturbed grains would grow deeper with higher velocity impacts, results instead show that increasing velocity may actually evoke a change in the grains' dissipative response that boosts lateral perturbation. Finally, we consider as a whole how sub-surface response could link with impactor dynamics to deepen our understanding of oblique, low-velocity impact events and help to improve mission outcomes.

We carry out experiments of low velocity normal impacts into granular materials that fill an approximately cylindrical 42 litre tub. Motions in the granular medium are tracked with an array of 7 embedded accelerometers. Longitudinal pulses excited by the impact attenuate and their shapes broaden and become smoother as a function of travel distance from the site of impact. Pulse propagation is not spherically symmetric about the site of impact. Peak amplitudes are about twice as large for the pulse propagating downward than at 45 degrees from vertical. An advection-diffusion model is used to estimate the dependence of pulse properties as a function of travel distance from the site of impact. The power law forms for pulse peak pressure, velocity and seismic energy depend on distance from impact to a power of -2.5 and this rapid decay is approximately consistent with our experimental measurements. Our experiments support a seismic jolt model, giving rapid attenuation of impact generated seismic energy into rubble asteroids, rather than a reverberation model, where seismic energy slowly decays. We apply our diffusive model to estimate physical properties of the seismic pulse that will be excited by the forthcoming DART mission impact onto the secondary, Dimorphos, of the asteroid binary (65803) Didymos system. We estimate that the pulse peak acceleration will exceed the surface gravity as it travels through the asteroid.

NASA's Double Asteroid Redirection Test (DART) mission is the first full-scale planetary defense mission. The target is the binary asteroid (65803) Didymos, in which the smaller component Dimorphos (∼164 m equivalent diameter) orbits the larger component Didymos (∼780 m equivalent diameter). The DART spacecraft will impact Dimorphos, changing the system’s mutual orbit by an amount that correlates with DART's kinetic deflection capability. The spacecraft collision with Dimorphos creates an impact crater, which reshapes the body. Also, some particles ejected from the DART impact site on Dimorphos eventually reach Didymos. Because Didymos’s rapid spin period (2.26 hr) may be close to its stability limit for structural failure, the ejecta reaching Didymos may induce surface disturbance on Didymos. While large uncertainties exist, nonnegligible reshaping scenarios on Didymos and Dimorphos are possible if certain conditions are met. Our analysis shows that given a surface slope uncertainty on Dimorphos of 45°, with no other information about its local topography, and if the DART-like impactor is treated as spherical, the ejecta cone crosses Didymos with speeds ≳14 m s−1 in 13% of simulations. Additional work is necessary to determine the amount of mass delivered to Didymos from the DART impact and whether the amount of kinetic energy delivered is sufficient to overcome cohesive forces in those cases. If nonnegligible (but small) reshaping occurs for either of these asteroids, the resulting orbit perturbation and reshaping are measurable by Earth-based observations.

There is a lack of curricula addressing the alarming rates of resident physician mistreatment. As the ACGME works to address diversity, equity, and inclusion in GME, there has been increasing attention paid to the issue of mistreatment. Previous studies have noted a high prevalence of mistreatment within GME. Despite this, there are few published interventions to address the mistreatment of residents. We developed a workshop for residents to provide an overview of mistreatment in residency and teach them REWIND (relax, express, why, inquire, negotiate, determine), a communication tool to address mistreatment directly.We designed a 60-minute workshop for residents with didactics on mistreatment in GME, followed by three case discussions. Four case scenarios were developed to represent different types of mistreatment and situations. We implemented the workshop twice and asked participants to self-rate proficiency around the workshop objectives with pre- and postsurveys.A total of 11 GME learners completed both the pre- and postsurveys between the two workshop implementations. GME learners who responded demonstrated significantly higher self-rated proficiency on each objective postworkshop compared to preworkshop (Our workshop improved participant self-rated proficiency around the mistreatment of resident physicians. The workshop can be used in the future as part of a multifaceted institutional response to mistreatment.

International audience; Over the last decades, simulations by discrete elements methods (DEM) have proven to be a reliable analysis tool in various domains of science and engineering. By providing access to the local physical mechanisms, DEM allows the exploration of microscopic based phenomena related to particles properties and interactions in various conditions and to revisit constitutive equations consequently. The growing computer power and memory now allow us to handle large collections of grains of various shapes and sizes by DEM simulations and in particular, it offers new perspectives in the exploration of the behavior of asteroids seen as self-gravitating and cohesive granular aggregates. In this paper we describe the Contact Dynamics (CD) method, a class of DEM based on non-smooth mechanics, and its implementation in the open-source software LMGC90. In contrast to more classical approach, Hard-and Soft-Sphere DEM, the CD method is based on an implicit time integration of the equations of motion and on a non-regularized formulation of mutual exclusion between particles. This numerical strategy is particularly relevant to the study of dense granular assemblies (even of large size) because it does not introduce numerical artefacts due to contact stiffness. So that it can be used for Small Body research, we implement a parallelised kd-tree and monitor the performance of the code as it simulates a number of granular systems. We provide examples of the simulation of the accretion of self-gravitating aggregates as well as their rotational disruption. We use the routines at our disposal in the code to monitor their behaviour through the entire evolution and find agreement with previous research.

The COVID-19 pandemic has disproportionately affected Hispanics in the United States, who make up 18% of US inhabitants but 29% of COVID-19 cases as of June 2021. Recent studies have attributed higher COVID-19 infection, hospitalization, and death rates among Hispanics to social determinants of health. Given that the majority of US Hispanics are bilingual or Spanish-dominant, it is imperative for health care providers to be prepared to discuss COVID-19 prevention and treatment in Spanish.We developed an interactive workshop aimed at increasing health professionals' confidence in discussing COVID-19 prevention, risk factors, and treatments with Spanish-speaking patients. Learners were expected to have an intermediate level or higher proficiency in medical Spanish. The workshop consisted of a PowerPoint presentation and English/Spanish scripts to facilitate interactive learning. The workshop was evaluated using a postworkshop questionnaire to assess learners' perceived confidence in communicating with Spanish-speaking patients.The workshop was implemented with 70 participants, who had diverse ethnoracial identities and professional roles, at five different medical schools. Fifty-three participants completed the postworkshop questionnaire. More than 50% reported near complete to complete confidence in meeting the three learning objectives.With Hispanics being the largest non-White ethnoracial group in the US and being disproportionally affected by COVID-19, it is essential for health professionals to access training tools that allow them to practice medical Spanish. This module can uniquely aid in the preparation of health professionals caring for Spanish-speaking patients who present with COVID-19 symptoms.

The purpose of this research work was to calibrate the Manning's roughness coefficient in rural non-instrumented basins using a distributed hydrological model. The process consisted of the selection of several basins with vegetal cover of forests and grasslands, and its subsequent experimental numerical study, in which the hydrological response hydrograph of each reference basin was obtained from the HEC-HMS software and the hydrograph to be calibrated was the Iber software, which is a hydrodynamic model based on the two-dimensional Saint Venant equations, solved by the finite volume method. Once the calibration process was carried out, the roughness coefficients with the best fit for each basin were identified with increases in precipitation, identifying the limitations of these values and the standard model used. Resumen El presente trabajo de investigación tuvo como finalidad la calibración del coeficiente de rugosidad de Manning en cuencas rurales no instrumentadas mediante un modelo hidrológico distribuido. El proceso consistió en la elección de varias cuencas con cobertura vegetal de bosques y pastos, y su posterior estudio numérico experimental en donde el hidrograma de respuesta hidrológica de cada cuenca de referencia fue obtenido del software HEC-HMS y el hidrograma a calibrarse fue el del software Iber, el cual es un modelo hidrodinámico basado en las ecuaciones de Saint Venant bidimensionales, resueltas mediante el método de volúmenes finitos. Una vez llevado a cabo el proceso de calibración, se identificaron los coeficientes de rugosidad con mejor ajuste para cada cuenca con incrementos de precipitación, identificándose las limitaciones de estos valores y del modelo patrón empleado.

We consider an impact on an asteroid that is energetic enough to cause resurfacing by seismic reverberation and just below the catastrophic disruption threshold, assuming that seismic waves are not rapidly attenuated. In asteroids with diameter less than 1 km we identify a regime where rare energetic impactors can excite seismic waves with frequencies near those of the asteroid's slowest normal modes. In this regime, the distribution of seismic reverberation is not evenly distributed across the body surface. With mass-spring model elastic simulations, we model impact excitation of seismic waves with a force pulse exerted on the surface and using three different asteroid shape models. The simulations exhibit antipodal focusing and normal mode excitation. If the impulse excited vibrational energy is long lasting, vibrations are highest at impact point, its antipode and at high surface elevations such as an equatorial ridge. A near equatorial impact launches a seismic impulse on a non-spherical body that can be focused on two additional points on an the equatorial ridge. We explore simple flow models for the morphology of vibration induced surface slumping. We find that the initial seismic pulse is unlikely to cause large shape changes. Long lasting seismic reverberation on Bennu caused by a near equatorial impact could have raised the height of its equatorial ridge by a few meters and raised two peaks on it, one near impact site and the other near its antipode., Comment: submitted to Icarus

Introduction A growing number of Liaison Committee on Medical Education–accredited allopathic medical schools offer formal bilingual (English and Spanish) medical education, and numerous other schools offer medical Spanish through elective workshops as part of their curricula. One significant health disparity in the Hispanic community is the incidence of HIV among Spanish-speaking men who have sex with men (MSM). Pre-exposure prophylaxis (PrEP) has emerged as an effective strategy to reduce the risk of HIV transmission. Methods We developed an education module to train clinicians to discuss PrEP with Spanish-speaking MSM. Our module is adapted from an English module on PrEP education. It includes a Spanish-language PowerPoint slide deck with information about PrEP as well as a Spanish-language videotaped scripted clinical encounter. Results The module was implemented on three occasions with 18 participants, and learners reported increased comfort in discussing and confidence in prescribing PrEP with Spanish-speaking patients. Discussion This workshop can be incorporated within medical Spanish curriculums offered at health professional schools and community-based organizations dedicated to reducing the HIV burden in the Spanish-speaking Hispanic community.

Introduction The AAMC prioritizes promoting a diverse and culturally competent workforce which is thought to have a positive impact on the health of people living in the US. There is a lack of diversity in the current landscape of academic medicine and strategies are needed to effect change. This module introduced undergraduate and graduate medical trainees to leadership skills and opportunities in curriculum innovation and reform by learning about and interacting with the office of medical education (OME) at their institutions. Methods We implemented a workshop using small-group case discussions and didactics to help medical students and residents learn how to: (1) describe the structure and functions of an OME, (2) describe leadership competencies associated with various roles within the OME, and (3) identify opportunities for trainees to engage with the OME on curricular innovation and reform, especially advancing diversity and inclusion. Results Across three sites, 45 learners completed partial or full workshop evaluations. Of learners, 22 (49%) were not knowledgeable and 13 (29%) were somewhat knowledgeable in identifying leadership opportunities for trainees to become engaged through the OME. There was a statistically significant increase in confidence after the workshop in “discussing an interdisciplinary approach to the creation of a medical education innovation,” and, “assessing the need for curricula change.” Over 90% of attendees agreed learning objectives were met. Discussion This workshop succeeded in promoting awareness of the structure and function of OMEs and confidence in seeking opportunities to become engaged in medical education, especially in advancing diversity and inclusion.

Introduction Exposing trainees to roles within medical school offices is an important, but often overlooked, component of academic medicine career development. This module described the roles and responsibilities of staff within the Office of Student Affairs (OSA) and opportunities for trainees to become engaged, lead, and develop student affairs-related competencies. Methods The 90-minute workshop was presented at three regional conferences at US medical schools between September and December 2019. Participants were medical students, residents, and fellows from multiple institutions. The workshop consisted of a didactic portion describing OSA responsibilities and guiding principles, reflection exercises to gauge learners' engagement with the OSA, and case discussions on how trainees have led scholarly student affairs-related projects. Results Among 28 participants, over 90%, agreed that each of the workshop objectives was met. Using the Wilcoxon signed-rank test, there was a statistically significant increase (p < .001) in participants' confidence to “list skills to be an effective advisor in the OSA,” and, “Advocate for student issues through the OSA.” Discussion Trainees not only have the opportunity to access services through the OSA, but also serve and develop foundational competencies to eventually serve in an OSA leadership position. This workshop provided trainees early exposure to OSA administration to realize a career in academic medicine beyond the faculty role.

We compare low velocity impacts that ricochet with the same impact velocity and impact angle into granular media with similar bulk density, porosity and friction coefficient but different mean grain size. The ratio of projectile diameter to mean grain length ranges from 4 in our coarsest medium to 50 in our finest sand. Using high speed video and fluorescent markers, we measure the ratio of pre- to post-impact horizontal and vertical velocity components, which we refer to as coefficients of restitution, and the angle of deflection caused by the impact in the horizontal plane. Coefficients of restitution are sensitive to mean grain size with the ratio associated with the horizontal velocity component about twice as large for our coarsest gravel as that for our finest sand. This implies that coefficients for hydro-static-like, drag-like and lift-like forces, used in empirical force laws, are sensitive to mean grain size. The coefficient that is most strongly sensitive to grain size is the lift coefficient which decreases by a factor of 3 between our coarsest and finest media. The deflection angles are largest in the coarser media and their size approximately depends on grain size to the 3/2 power. This scaling is matched with a model where momentum transfer takes place via collisions with individual grains. The dependence of impact mechanics on substrate size distribution should be considered in future models for populations of objects that impact granular asteroid surfaces., Comment: Link to the high speed videos for the 4 experiments tracked and discussed: https://youtube.com/playlist?list=PLYnpHw29go3pCWwm554fwR6jNFvB5qVQn Submitted to the journal Icarus on September 12, 2021

As protests against racism occur all over the United States and medical institutions face calls to incorporate antiracism and health equity curricula into professional training and patient care, the antiracism discourse has largely occurred through a Black/African American and White lens. Hispanics, an umbrella category created by the U.S. government to include all people of Spanish-speaking descent, are the largest minority group in the country. Hispanics are considered an ethnic rather than a racial group, although some Hispanics self-identify their race in terms of their ethnicity and/or country of origin while other Hispanics self-identify with any of the 5 racial categories used by the U.S. government (White, Black/African American, American Indian or Alaska Native, Asian, or Native Hawaiian or Other Pacific Islander). Expanding the antiracism discourse in medicine to include Hispanic perspectives and the diversity of histories and health outcomes among Hispanic groups is crucial to addressing inequities and disparities in health and medical training. A lack of inclusion of Hispanics has contributed to a growing shortage of Hispanic physicians and medical school faculty in the United States as well as discrimination against Hispanic physicians, trainees, and patients. To reverse this negative trend and advance a health care equity and antiracist agenda, the authors offer steps that medical schools, academic medical centers, and medical accreditation and licensing bodies must take to increase the representation of Hispanics and foster their engagement in this evolving antiracism discourse.

Introduction Increasing faculty and leader diversity has been recommended as a way for health care organizations to achieve cultural competence in their patient care mission. Given the low numbers of underrepresented groups in medical school leadership positions, teaching diverse students and trainees the concept of leadership as influence may empower them to become more involved and bring diverse perspectives to their organizations. Methods This 70-minute workshop consisted of a short presentation, a self-assessment, small- and large-group discussions, and case studies to: (1) describe the importance of diversity in medical school leadership, (2) define leadership, (3) define self-leadership, and (4) assess one's own self-leadership skills. The workshop was implemented at three US medical schools to diverse medical students and residents between September and December of 2019. Pre- and postworkshop evaluations were analyzed. Results Greater than 95% of learners (n = 66) agreed that the workshop's learning objectives were met. Comments suggested participants appreciated learning about the lack of diversity among medical school leaders and the importance of cultivating their role in diversity in academic medicine. The case studies were highly rated and considered effective tools for learning. Discussion This submission defined an empowering notion of leadership as influence. It taught learners that we can all lead (by influence) if we can improve our own self-leadership skills and become involved and bring diverse perspectives to health care organizations. Future research may focus on longer-term follow-up of participants to reassess their self-leadership skills and describe their level of involvement in their organizations.

Introduction Encouraging trainee engagement with the Office of Admissions can be an effective method of training for a future career in academic medicine and allow trainees to develop critical leadership skills. Methods This workshop consisted of a short didactic presentation, a large-group activity, and case discussions in an effort to address four objectives describing the functions of the Office of Admissions, as well as identifying opportunities for involvement and leadership skills fostered through engaging in admissions activities. The module was administered to diverse students and residents at three regional conferences at US medical schools between September and December 2019. Pre- and postworkshop surveys were used to analyze the efficacy of the workshop. Results More than 95% of the 70 learners agreed that all four objectives had been met. Additionally, trainees had a statistically significant increase (p < .001) in confidence in their ability to address new issues, such as Deferred Action for Childhood Arrivals or LGBT inclusion, through the admissions process and engage in discussion about admissions policies and practices. Discussion This workshop was an effective tool for introducing trainees to leadership opportunities in academic medicine via involvement with the Office of Admissions. During the workshop, students expressed feedback about wanting more ways to become involved and more examples of student involvement. Attendees might also benefit from being encouraged to research the admissions processes and leadership structures at their respective institutions.

Spin off events and impacts can eject boulders from an asteroid surface and rubble pile asteroids can accumulate from debris following a collision between large asteroids. These processes produce a population of gravitational bound objects in orbit that can impact an asteroid surface at low velocity and with a distribution of impact angles. We present laboratory experiments of low velocity spherical projectiles into a fine granular medium, sand. We delineate velocity and impact angles giving ricochets, those giving projectiles that roll-out from the impact crater and those that stop within their impact crater. With high speed camera images and fluorescent markers on the projectiles we track spin and projectile trajectories during impact. We find that the projectile only reaches a rolling without slipping condition well after the marble has reached peak penetration depth. The required friction coefficient during the penetration phase of impact is 4-5 times lower than that of the sand suggesting that the sand is fluidized near the projectile surface during penetration. We find that the critical grazing impact critical angle dividing ricochets from roll-outs, increases with increasing impact velocity. The critical angles for ricochet and for roll-out as a function of velocity can be matched by an empirical model during the rebound phase that balances a lift force against gravity. We estimate constraints on projectile radius, velocity and impact angle that would allow projectiles on asteroids to ricochet or roll away from impact, finally coming to rest distant from their initial impact sites., Link to the high speed videos for the 3 experiments tracked and discussed: https://www.youtube.com/playlist?list=PLYnpHw29go3rKYOvM4WEQkHWYYIGgRC-E Preliminary results presented at American Geophysical Union (AGU) 2019 Fall Meeting (P43D-3497). Submitted to the journal Icarus on February 3, 2020

Introduction Hispanics are the largest minority group in the US at 18% of the population, of which Puerto Ricans are the second largest subgroup. Puerto Ricans have poorer health status than other US Hispanic and non-Hispanic populations. Thus, health care providers need to know about and distinguish the health care problems of Puerto Ricans to improve their health. Although there are some published curricula addressing how to provide health care to Hispanic populations, none address the specific needs of Puerto Ricans. Methods We developed a 60-minute interactive workshop consisting of a PowerPoint presentation and case discussion aimed at increasing health care providers' knowledge and understanding of the historical perspective that led to Puerto Rican identity, health issues and disparities, and the health care access problems of mainland and islander Puerto Ricans. Evaluation consisted of pre- and postworkshop questionnaires. Results There were a total of 64 participants with diverse ethnoracial identities including medical students, residents, faculty, physicians, researchers, administrators, and students/faculty from nursing, occupational therapy, genetic counseling, biomedical sciences, and social work programs. A comparison of pre- and postworkshop data showed a statistically significant increase in participants' confidence in meeting all learning objectives. Participants positively commented on the interactive nature of the workshop, the case discussion, and the historical perspective provided. Discussion With the increasing migration of Puerto Ricans to the US mainland this module can uniquely improve the preparation of current and future health care providers to provide competent care to Puerto Rican patients.

Using a damped mass-spring model, we simulate wobble of spinning homogeneous viscoelastic ellipsoids undergoing non-principal axis rotation. Energy damping rates are measured for oblate and prolate bodies with different spin rates, spin states, viscoelastic relaxation timescales, axis ratios, and strengths. Analytical models using a quality factor by Breiter et al. (2012) and for the Maxwell rheology by Frouard & Efroimsky (2018) match our numerical measurements of the energy dissipation rate after we modify their predictions for the numerically simulated Kelvin-Voigt rheology. Simulations of nearly spherical but wobbling bodies with hard and soft cores show that the energy dissipation rate is more sensitive to the material properties in the core than near the surface. The sensitivity to viscoelastic model implies that inferred statistics of tumbling lifetimes in asteroids might be interpreted in terms of differences in their material properties., accepted MNRAS

Introduction As a result of the common belief that professionals in academic medicine make less money than their private practice counterparts, as well as the rising cost of medical school and subsequent loans, medical students and residents alike are dissuaded from pursuing careers in academia. However, with greater knowledge of loan repayment programs and financial planning, students can make informed decisions about entering the field of academia. Methods Using the Kern model, a workshop was developed to educate medical students considering an academic career about financial resources, loan repayment, student debt, and the importance of budgets. The workshop also encouraged reflection on personal and financial factors that influence career choice. Results The workshop was implemented at five regional conferences with a total of 113 participants. After participating in the workshop, survey data showed that participants were statistically less likely to agree with the statement “Student debt will hinder my ability to pursue an academic medicine career,” and more likely to agree with the statement “Academic medicine is a financially viable career choice for me” and “A career in academic medicine will provide a comfortable salary.” Over 95% of respondents agreed or strongly agreed that each objective was met. Discussion This workshop provided an interactive and reflective method to increase participants' awareness of factors that influence financial considerations when considering postgraduate career choices. It highlighted factors that may be particularly relevant for an academic career choice and of resources available, especially loan repayment programs, to ensure a financially viable academic career.

Introduction While great strides have been made in favor of the LGBT community overall, transgender individuals are still facing many legal challenges and suffer from more marked health issues and disparities compared to other members of the LGBT community. Our multimodal transgender curriculum was designed in accordance with the Kern model to address educational gaps in the area of transgender health. Methods This three-part module consists of: (1) a didactic PowerPoint presentation reviewing unique health issues and disparities experienced by transgender patients, (2) a small-group session viewing and analyzing a pair of videos showcasing competent and poor communication between a provider and a transgender patient, and (3) a large-group patient panel featuring members of the transgender community. Results One hundred and sixty-one students returned pre- and postworkshop surveys with 123 matched pairs. When comparing participants reported pre- and postworkshop confidence levels, the mean rating increased significantly for all three learning objectives. Based on a 5-point Likert scale (1 = poor, 5 = excellent), participants’ mean ratings were highest for the patient panel at 4.5, compared to 3.9 for the large-group didactic lecture, and 3.8 for the small-group video session. Discussion The use of this multimodal approach using a didactic session, video-based case discussion, and patient panel provided a strong foundation and primer for transgender health and resulted in an increase in learner confidence in module objectives regarding care for the transgender community.

Introduction Gaps exist in educational materials addressing LGBTQ patient care and LGBTQ health. One such area is prescribing HIV pre-exposure prophylaxis (PrEP) for men who have sex with men (MSM). PrEP awareness, familiarity, and comfort in prescribing are very important in the rollout and success of PrEP as a preventative measure. Our needs assessments showed a lack of familiarity and comfort among clinicians/medical students in prescribing PrEP. Furthermore, studies have shown that since its launch as an effective prevention method of HIV transmission, PrEP has not been widely prescribed to at-risk populations. Educating clinicians about PrEP may increase its use among high-risk MSM populations and reduce the incidence of HIV infections. Methods For medical students, we developed a didactic presentation and video recording discussing (1) a brief history of HIV prevention, (2) indications for PrEP prescription, (3) medical testing for PrEP onboarding, (4) common PrEP side effects, and (5) appropriate follow-up and testing for PrEP maintenance and discontinuation. We also developed a videotaped clinical encounter demonstrating communication skills used in PrEP counseling. Pre- and postworkshop surveys assessed participants’ PrEP attitudes and knowledge. Results All 43 survey respondents were second- through fourth-year medical students. Pre- and postpresentation evaluation of questions assessing comfort demonstrated a statistically significant improvement in level of comfort with understanding when to prescribe PrEP and in level of knowledge in prescribing PrEP. Discussion Workshop participants acknowledged their training gaps in PrEP prescribing and acquired knowledge and comfort with prescribing PrEP for at-risk populations.

The goal of this chapter is to give an outline of how trainees can create scholarship from community service. The chapter will begin with basic definitions of community service, community engagement, service learning and opportunities for scholarship through community service. It will highlight trends in service activities engaged in by trainees, as they progress from their pre-medical to resident training, to show the myriad of possibilities and potential alignment with personal and professional interests. The concept of value-based alignment will be introduced to help readers align their activities not only with personal and professional interests but also community needs and institutional mission and strategic planning, yielding greater fulfillment and advancement. The chapter then introduces examples of frameworks and models to help transform community service work to scholarship with case scenarios to showcase how frameworks and models can be applied to achieve scholarship.

Demystifying the process of the critical transition from trainee to academic physician is an important goal in efforts to attract and retain talent in academic medical centers. Providing you with knowledge, skills, and resources that allow for informed decision-making when pursuing a position in academic medicine may help you gain greater self-efficacy towards obtaining an academic physician job. In this chapter, information about finding an academic position after residency is provided along with important considerations for selecting an academic position and preparing for successful academic career progression and promotion.