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The electron cyclotron (EC) heating & current drive (H&CD) system on ITER provides plasma heating by generating, transmitting, and launching high-intensity, high-frequency (170 GHz) electromagnetic wave energy steerable across the plasma cross-section. The transmission line (TL) subsystem connects the Matching Optics Unit (MOU) on each of the 24 gyrotrons to the 32 feed points in the four upper launchers and the 24 feed points in the equatorial launcher. Each TL must be able to operate at up to 1.2 MW of input power for up to 1 hour pulse lengths. The TL system contains 50 mm water-cooled corrugated waveguide, 90o miter bends, 140o miter bends, polarizer miter bend pairs, switches, expansion units, pumpouts, DC breaks, MOU-TL adapters, Radio Frequency (RF) loads, and isolation shutter valves. A detailed finite element analysis has been used to verify the thermo-mechanical performance of each component. The microwave performance has been analyzed using a 2-D electromagnetic code combined with a Monte Carlo code. This approach allows the impact of manufacturing and installation tolerances to be assessed and optimized to provide a high probability of achieving the system performance requirements. Prototypes of the waveguide and TL components have been fabricated and tested at high-power. Production contracts are now being issued for fabrication and delivery of the waveguide and components to ITER.

The ITER Electron Cyclotron Resonance Heating (ECRH) & Current Drive (ECCD) system is planned to be progressively installed and commissioned following the four stage approach of the ITER Research Plan. Starting with an injection of up to 5.8 MW from one Upper Launcher (UL) in the vacuum vessel to assist the plasma breakdown during First Plasma (FP) operation, the system will then be extended to achieve a capability of 20 MW injected power in Pre-Fusion Plasma Operation (PFPO) and Fusion Power Operation (FPO) phases. Development of optical modelling was required to characterize the optical performance of the FP configuration with the so-called First Plasma Protection Components. An optical 3D model using Zemax OpticStudio® has been developed and extended to the UL. Effects of higher order modes, thermal deformations and tolerances on the UL functionality have been characterized and are presented. Finally, in preparation of plasma operation and in the frame of the EC system upgrade layout optimisation, ECRH-ECCD modelling is being undertaken within the ITER Integrated Modelling and Analysis (IMAS) suite.

ProblemOur nation faces an urgent need for more primary care (PC) physicians, yet interest in PC careers is dwindling. Students from underrepresented in medicine (UIM) backgrounds are more likely to choose PC and practice in underserved areas yet their representation has declined. Accelerated PC programs have the potential to address workforce needs, lower educational debt, and diversify the physician workforce to advance health equity.ApproachWith support from Kaiser Permanente Northern California (KPNC) and the American Medical Association's Accelerating Change in Medical Education initiative, University of California School of Medicine (UC Davis) implemented the Accelerated Competency-based Education in Primary Care (ACE-PC) program - a six-year pathway from medical school to residency for students committed to health equity and careers in family medicine or PC-internal medicine. ACE-PC accepts 6-10 students per year using the same holistic admissions process as the 4-year MD program with an additional panel interview that includes affiliated residency program faculty from UC Davis and KPNC. The undergraduate curriculum features: PC continuity clinic with a single preceptor throughout medical school; a 9-month longitudinal integrated clerkship; supportive PC faculty and culture; markedly reduced student debt with full-tuition scholarships; weekly PC didactics; and clinical rotations in affiliated residency programs with the opportunity to match into specific ACE-PC residency tracks.OutcomesSince 2014, 70 students have matriculated to ACE-PC, 71% from UIM groups, 64% are first-generation college students. Of the graduates, 48% have entered residency in family medicine and 52% in PC-internal medicine. In 2020, the first graduates entered the PC workforce; all are practicing in California, including 66% at federally qualified health centers, key providers of underserved care.

This Viewpoint discusses what higher education institutions can learn from UC Davis when it comes to ensuring equity for their students now that the US Supreme Court has eliminated race-conscious college admissions.

ImportanceDespite decades-long calls for increasing racial and ethnic diversity, the medical profession continues to exclude members of Black or African American, Hispanic or Latinx, and Indigenous groups.ObjectiveTo describe US medical school admissions leaders' experiences with barriers to and advances in diversity, equity, and inclusion.Design, setting, and participantsThis qualitative study involved key-informant interviews of 39 deans and directors of admission from 37 US allopathic medical schools across the range of student body racial and ethnic composition. Interviews were conducted in person and online from October 16, 2019, to March 27, 2020, and analyzed from October 2019 to March 2021.Main outcomes and measuresParticipant experiences with barriers to and advances in diversity, equity, and inclusion.ResultsAmong 39 participants from 37 medical schools, admissions experience ranged from 1 to 40 years. Overall, 56.4% of participants identified as women, 10.3% as Asian American, 25.6% as Black or African American, 5.1% as Hispanic or Latinx, and 61.5% as White (participants could report >1 race and/or ethnicity). Participants characterized diversity broadly, with limited attention to racial injustice. Barriers to advancing racial and ethnic diversity included lack of leadership commitment; pressure from faculty and administrators to overemphasize academic scores and school rankings; and political and social influences, such as donors and alumni. Accreditation requirements, holistic review initiatives, and local policy motivated reforms but may also have inadvertently lowered expectations and accountability. Strategies to overcome challenges included narrative change and revision of school leadership structure, admissions goals, practices, and committee membership.Conclusions and relevanceIn this qualitative study, admissions leaders characterized the ways in which entrenched beliefs, practices, and power structures in medical schools may perpetuate institutional racism, with far-reaching implications for health equity. Participants offered insights on how to remove inequitable structures and implement process changes. Without such action, calls for racial justice will likely remain performative, and racism across health care institutions will continue.

This article describes the "The Admissions Revolution: Bold Strategies for Diversifying the Healthcare Workforce" conference, which preceded the 2022 Beyond Flexner Alliance Conference and called for health professions institutions to boldly reimagine the admission process to diversify the health care workforce. Proposed strategies encompassed 4 key themes: admission metrics, aligning admission practices with institutional mission, community partnerships to fulfill social mission, and student support and retention. Transformation of the health professions admission process requires broad institutional and individual effort. Careful consideration and implementation of these practices will help institutions achieve greater workforce diversity and catalyze progress toward health equity.

Introduction: Understanding how abundance, productivity and distribution of individual species may respond to climate change is a critical first step towards anticipating alterations in marine ecosystem structure and function, as well as developing strategies to adapt to the full range of potential changes. Methods: This study applies the NOAA (National Oceanic and Atmospheric Administration) Fisheries Climate Vulnerability Assessment method to 64 federally-managed species in the California Current Large Marine Ecosystem to assess their vulnerability to climate change, where vulnerability is a function of a species’ exposure to environmental change and its biological sensitivity to a set of environmental conditions, which includes components of its resiliency and adaptive capacity to respond to these new conditions. Results: Overall, two-thirds of the species were judged to have Moderate or greater vulnerability to climate change, and only one species was anticipated to have a positive response. Species classified as Highly or Very Highly vulnerable share one or more characteristics including: 1) having complex life histories that utilize a wide range of freshwater and marine habitats; 2) having habitat specialization, particularly for areas that are likely to experience increased hypoxia; 3) having long lifespans and low population growth rates; and/or 4) being of high commercial value combined with impacts from non-climate stressors such as anthropogenic habitat degradation. Species with Low or Moderate vulnerability are either habitat generalists, occupy deep-water habitats or are highly mobile and likely to shift their ranges. Discussion: As climate-related changes intensify, this work provides key information for both scientists and managers as they address the long-term sustainability of fisheries in the region. This information can inform near-term advice for prioritizing species-level data collection and research on climate impacts, help managers to determine when and where a precautionary approach might be warranted, in harvest or other management decisions, and help identify habitats or life history stages that might be especially effective to protect or restore.

Patients with valvular heart disease may present with or without symptoms. A thorough cardiac physical examination can identify patients who require further evaluation and management. Although the utility of different cardiac findings varies widely, diastolic murmurs indicate important underlying valvular pathology requiring further investigation, typically with echocardiography. The proper examination of patients with systolic murmurs, the most common murmurs in clinical practice, is fundamental to cost-effective care. We will review the key components of the cardiac examination and findings relevant to functional murmurs, aortic stenosis, mitral valve prolapse and regurgitation, tricuspid regurgitation, hypertrophic cardiomyopathy, aortic regurgitation, and mitral stenosis.

PurposeTo conduct a post-Americans with Disabilities Act Amendments Act of 2008 multisite, multicohort study called the Pathways Project to assess the performance and trajectory of medical students with disabilities (SWDs).MethodFrom June to December 2020, the authors conducted a matched cohort study of SWDs and nondisabled controls from 2 graduating cohorts (2018 and 2019) across 11 U.S. MD-granting medical schools. Each SWD was matched with 2 controls, one from their institution and, whenever possible, one from their cohort for Medical College Admission Test score and self-reported gender. Outcome measures included final attempt Step 1 and Step 2 Clinical Knowledge scores, time to graduation, leave of absence, matching on first attempt, and matching to primary care.ResultsA total of 171 SWDs and 341 controls were included; the majority of SWDs had cognitive/learning disabilities (118/171, 69.0%). Compared with controls, SWDs with physical/sensory disabilities had similar times to graduation (88.6%, 95% confidence interval [CI]: 77.0, 100.0 vs 95.1%, 95% CI: 90.3, 99.8; P = .20), Step 1 scores (229.6 vs 233.4; P = .118), and match on first attempt (93.9%, 95% CI: 86.9, 100.0 vs 94.6%, 95% CI: 91.8, 97.4; P = .842), while SWDs with cognitive/learning disabilities had lower Step 1 scores (219.4; P < .001) and were less likely to graduate on time (81.2%, 95% CI: 69.2, 93.2; P = .003) and match on first attempt (85.3%, 95% CI: 78.0, 92.7; P = .009). Accommodated SWDs had Step 1 scores that were 5.9 points higher than nonaccommodated SWDs (95% CI: -0.7, 12.5; P = .08).ConclusionsStructural barriers remain for SWDs with cognitive/learning disabilities, which could be partially mitigated by accommodations on high-stakes exams.

This article offers two case studies to illustrate the challenges in applying mainstream engineering educational training in a different culture and context while also offering some suggestions for more integrated and context-based educational approaches. The overall goal is not to dissuade energetic and well-meaning engineers looking to make a difference in the lives of communities around the world (although it is clear that in many cases, engineering solutions implemented at community levels have had mixed results) but rather to suggest that developing skills and contextual awareness to supplement those that they receive in traditional engineering programs is necessary to succeed in being part of a process of positive change in communities. This article will hopefully inspire engineering students and engineers to reflect on and ask important questions before they design solutions for communities different from the ones they grew up in. [ABSTRACT FROM AUTHOR]

The two-stage process for the treatment of rare earth phosphate minerals, involving an oxalic acid conversion leach and subsequent EDTA dissolution, has been demonstrated as a promising alternative to conventional extraction methods. To underpin a more detailed understanding, this work serves to further develop knowledge of the linkage between the stages and key practical aspects of the operation of the EDTA dissolution. A more detailed treatment of the phenomena observed in the EDTA treatment, characteristics of the solids, mass loss in dissolution, and the impact of parameter alterations in both stages provide greater holistic knowledge of the proposed flowsheet and considerations that will need to be addressed when increasing scale. Acid production (indicated by a pH decrease) in the EDTA dissolution stage was shown to be a feature of the reaction and not of residual acid associated with the solids from the oxalic acid stage. The consistency with which the rare earths were dissolved with respect to the phosphorus provided greater confidence that Nd and Pr (greater dissolution than P) are recovered at a higher efficiency than Ce and La (poorer dissolution than P). This was only not the case at high solids loading across both tests, leading to both oxalate and EDTA-deficient systems, respectively. Under high conversion conditions, it was demonstrated that Nd and Pr recoveries into solution approaching 70% were achieved. This equated to in excess of 17 gL−1 of total rare earths in solution. Solid/liquid separation was shown to be a significant challenge, created by both the fine particle size distribution of the leached residue and the dispersant nature of EDTA. [ABSTRACT FROM AUTHOR]

Global warming has significantly altered plant phenology by advancing the timing of leaf emergence, impacting vegetation productivity and adaptability. Winter and spring temperatures have commonly been used to explain spring phenology shifts, but we still lack a solid understanding of the effects of interactions between conditions in different seasons. This study utilizes normalized difference vegetation index (NDVI) and meteorological data to examine the effects of changes in winter and spring temperatures and precipitation on the start of the vegetation growing season (SOS) at high latitudes in China from 1982 to 2015. We found that SOS in Northeast China, as a whole, showed a weak advancing trend (moving earlier in the year), but with obvious regional differences. Even within the same vegetation type, changes in SOS were faster in the cold north (1.9 days/decade) and the cold and dry northwest (1.6 days/decade) than the regional averages for deciduous needleleaf forests (DNF; 1.2 days/decade) and grasslands (0.6 days/decade). Increases in spring temperatures dominate forest SOS advancement, while grassland SOS is mainly influenced by winter and spring precipitation. Decreases in winter minimum temperature (Tmin) enhance the spring temperature sensitivity of SOS. The way that winter precipitation regulates the spring temperature sensitivity of SOS differs among vegetation types: increasing sensitivity in grasslands but suppressing it in DNF. The moderating effects of winter conditions account for the greatest part of the regional differences in the magnitude of change in SOS. Our findings highlight that, although rising spring temperatures significantly affect SOS, winter Tmin and precipitation are crucial for understanding spatial SOS differences, particularly in cold, arid high-latitude regions. Winter conditions play an essential role in regulating the response of vegetation SOS to spring climate at high latitudes. These results suggest that considering the moderating effect of winter climate can facilitate more accurate predictions of temperature-driven phenological changes under future climate change. [ABSTRACT FROM AUTHOR]

Training programs in pulmonary and critical care medicine have greatly expanded in the past decade, yet they do not reflect the racial/ethnic and economic diversity of the United States, which has significant implications for health equity. The lack of representation across medical education is likely to worsen with the recent Supreme Court decision banning affirmative action. The authors review health disparities in pulmonary and critical care medicine, the relationship of the workforce to health equity, and 10 tactics for addressing this urgent public health issue. [ABSTRACT FROM AUTHOR]

With the acceleration of global warming, droughts are expected to both intensify and become more frequent. More so than forests, the productivity of grasslands is largely controlled by soil moisture and is highly susceptible to drought. Drought can impact grasslands though the effects may lag and accumulate over time. Because prior research has mainly focused on the annual or growing season scale, it remains unclear whether there are seasonal differences in the cumulative and lagged effects (CALEs) of drought. This study uses Normalized Difference Vegetation Index (NDVI) and Standardized Precipitation Evapotranspiration Index (SPEI) data to explore the seasonal characteristics of the CALEs of drought on grassland growth in East Asia from 2001 to 2020. The main results include the following: (1) More than 40% of grasslands are significantly affected by the CALEs of drought for all three seasons (spring, summer, and autumn). (2) Grasslands are more sensitive to the CALEs of drought in summer. The spatial variability of the cumulative time scale is the greatest in spring, whereas the spatial variability of the lagged time scale is the greatest in summer. The lag time scale gradually shortens as moisture decreases in summer and autumn but shows an inverted U-shape in spring. As drought conditions intensify, the cumulative time scale gradually increases in spring and autumn, while gradually decreasing in summer. (3) The dominant drought effects vary among different seasons: the lagged effect (LE) predominates in spring and autumn, whereas in summer it is the cumulative effect (CE) that dominates. The LE exceeds the CE in 54.89% of the study area during the growing season. We emphasize that annual- or growing season-scale studies of drought CE and LE may obscure seasonal response characteristics. Given the seasonal nature of droughts and the seasonally varying sensitivities of grassland growth to these droughts, the impacts on vegetation fluctuate significantly across different seasons. The results help us more accurately predict grassland ecosystem changes under the background of global warming and the increasing probability of severe drought, providing important reference values for future grassland ecological protection and planning. [ABSTRACT FROM AUTHOR]

Objective: Many mark–recapture models assume that releases and recaptures are discrete events, and researchers often aggregate continuous recapture data (e.g., passive integrated transponder [PIT] detections) into coarse temporal scales to satisfy this assumption. This temporal discretization could result in parameter biases by ignoring the individual heterogeneity in the time susceptible to mortality after recapture and the conditions experienced (e.g., temperature and predation risk) before and after recapture. Our objectives were to (1) estimate the amount of bias in survival and emigration rates due to different temporal discretization durations when recapture events occur continuously and (2) apply this semicontinuous model to estimate rates of early emigration and overwinter survival for Coho Salmon Oncorhynchus kisutch in a coastal California watershed. Methods: We developed a semicontinuous time multistate mark–recapture model to separately estimated emigration and survival rates throughout the year. We used weekly time‐varying occasions paired with discrete spatial states and conducted extensive simulation trials to explore potential model bias. We then applied the model to an existing 4‐year dataset of Coho Salmon PIT tag detections. Result: Our simulations indicated that that the amount of bias in survival and movement rates decreased as the temporal discretization duration decreased. The confidence interval of the bias estimates included zero with a duration of 8 days, indicating that this duration was sufficiently short to model movement and survival. Results from our Coho Salmon analysis suggest that overwinter survival rate ranged from 0.72 to 0.83, which is higher than previous estimates for Coho Salmon in this region. We estimate that a substantial proportion of smaller juveniles (0.21–0.28 annually) move to downstream nonnatal rearing habitats before the spring smolt migration. Conclusion: Our semicontinuous modeling approach can be implemented relatively easily and used to analyze continuous detection data to accurately estimate survival and movement rates. Our analysis of Coho Salmon PIT tag detections implies that previous low estimates of apparent overwinter survival of Coho Salmon were partially due to high movement rates to alternative rearing locations. This contrasts with conclusions from the previous research that suggested that overwinter survival was a major limiting factor for population recovery and implies that species recovery may be improved by considering multiple emigration patterns in the design of future research, monitoring, and restoration projects. Impact statementGrouping continuous mark–recapture data into single recapture events (e.g., monthly or seasonal) can bias estimates of survival and movement rates from mark–recapture models. [ABSTRACT FROM AUTHOR]

Soil aggregates are important indicators of soil structure stability and quality. The black soil region of northeast China, known for its high agricultural productivity, faces significant challenges due to soil erosion. This study investigates the impact of terracing on the stability and erodibility characteristics of soil aggregates in sloped farmlands, which is crucial for this important agricultural area. Three research sites with the same basic management modes were selected along a latitudinal gradient, from the mid-temperate zone to the cold temperate zone, in the black soil region of northeast China. The Savinov method was used to analyze the differences in soil aggregate size distribution, stability characteristics, and soil erodibility between terraced and non-terraced slopes at each research site. The results showed that terracing increased the content of large soil aggregates (>0.25 mm) by 5.38–6.35%, with the increase becoming more pronounced from north to south. The improvement in soil structure varied by location and slope position, with the most significant improvement at the middle slope position. Terracing enhanced soil aggregate stability, reduced soil erodibility, and improved soil structure by increasing clay and soil organic matter (SOM) content and reducing soil bulk density (BD), promoting the conversion of small aggregates to large aggregates. Soil stability indicators such as water-stable aggregates (WSAs), mean weight diameter (MWD), and geometric mean diameter (GMD) were dominated by aggregates > 5 mm, while erodibility indicators such as fractal dimensions (Ds) and the soil erodibility factor (K values) were mainly influenced by aggregates < 0.25 mm. Terraces can improve the soil structure and stability of sloping farmland by increasing the content of large soil aggregates and enhancing overall soil quality. The benefits of these improvements increase with latitude. These findings provide critical insights for determining effective management practices for sloped farmlands in the black soil region under various site conditions. They offer scientific evidence for preventing soil erosion and improving soil quality, thus supporting the sustainable development strategy for protecting black soil and ensuring long-term agricultural productivity. [ABSTRACT FROM AUTHOR]