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OBJECTIVE: To identify individual-level early warning indicators of virologic failure in HIV patients receiving antiretroviral therapy (ART) in South Africa. DESIGN: A matched case-control study of individuals with and without virologic failure (VF) (>5 months on ART and HIV-1 plasma viral load >1,000 copies/mL) was conducted between June 2014 and June 2018. Of the 1,000 participants enrolled in the parent cohort, 96 experienced VF, and 199 additional controls were identified from the parent cohort and matched 1:2 (some matched 1:3) for sex, age, ART duration, and site. Participants were interviewed while clinical, pharmacy refill, laboratory, and objective pharmacological data were obtained. Multivariate conditional logistic regression models were constructed using model selection to identify factors associated with VF. Significant determinants of VF were identified using an alpha level of 0.05. RESULTS: In a full conditional model, higher cumulative ART adherence, quantified using tenofovir-diphosphate concentrations in dried blood spots (OR 0.26) and medication possession ratio (OR 0.98) were protective against VF, whereas an increase in total depression score (OR 1.20) was predictive of VF. CONCLUSION: This analysis demonstrates the importance of depression as a key individual-level early warning indicator of VF. Efforts to address mental health concerns among patients with people living with HIV could improve virologic suppression.
OBJECTIF: Identifier les indicateurs d'alerte précoce au niveau individuel de l'échec virologique chez les patients séropositifs recevant un traitement antirétroviral (TAR) en Afrique du Sud. MÉTHODE: Une étude cas-témoins appariée de personnes avec et sans échec virologique (FV, pour l'anglais « virologic failure ¼) (>5 mois sous ART et charge virale plasmatique du VIH-1 >1 000 copies/ml) a été menée entre juin 2014 et juin 2018. Sur les 1 000 participants inscrits dans la cohorte parente, 96 ont présenté une FV et 199 témoins supplémentaires ont été identifiés dans la cohorte parentale et appariés 1:2 (certains appariés 1:3) pour le sexe, l'âge, la durée du TAR et le site. Les participants ont été interrogés pendant que des données cliniques, de renouvellement de pharmacie, de laboratoire et pharmacologiques objectives ont été obtenues. Des modèles de régression logistique conditionnelle multivariée ont été construits à l'aide d'une sélection de modèles pour identifier les facteurs associés à la FV. Les déterminants significatifs de la FV ont été identifiés à l'aide d'un niveau alpha de 0,05. RÉSULTATS: Dans un modèle conditionnel complet, une observance cumulative plus élevée du TAR, quantifiée à l'aide des concentrations de ténofovir-diphosphate dans les gouttes de sang séché (OR 0,26) et du ratio de possession de médicaments (OR 0,98) protégeait contre la FV, tandis qu'une augmentation du score de dépression totale (OR 1,20) était prédictive de la FV. CONCLUSION: Cette analyse démontre l'importance de la dépression en tant qu'indicateur précoce clé au niveau individuel de la FV. Les efforts visant à résoudre les problèmes de santé mentale chez les personnes vivant avec le VIH pourraient améliorer la suppression virologique.
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BACKGROUND: Programmed death receptor ligand 1 (PD-L1) tumor proportion score (TPS) and tumor mutational burden (TMB) are key predictive biomarkers for immune checkpoint inhibitor (ICI) efficacy in non-small-cell lung cancer (NSCLC). Data on their variation across multiple samples are limited. PATIENTS AND METHODS: Patients with NSCLC and multiple PD-L1 TPS and/or TMB assessments were included. Clinicopathologic and genomic data were analyzed according to PD-L1 and TMB variation. RESULTS: In total, 402 PD-L1 sample pairs and 413 TMB sample pairs were included. Concordance between pairs was moderate for PD-L1 (ρ = 0.53, P < 0.0001) and high for TMB (ρ = 0.80, P < 0.0001). Shorter time between biopsies correlated with higher concordance in PD-L1, but not in TMB. Major increases (ΔTPS ≥ +50%) and decreases (ΔTPS ≤ -50%) in PD-L1 were observed in 9.7% and 8.0% of cases, respectively. PD-L1, but not TMB, decreased with intervening ICI (P = 0.02). Acquired copy number loss of CD274, PDCD1LG2, and JAK2 were associated with major decrease in PD-L1 (q < 0.05). Among patients with multiple PD-L1 assessments before ICI, cases where all samples had a PD-L1 ≥1%, compared to cases with at least one sample with PD-L1 <1% and another with PD-L1 ≥1%, achieved improved objective response rate and progression-free survival (PFS). Among patients with at least one PD-L1 <1% and one ≥1% before ICI, cases where the most proximal sample was PD-L1 ≥1% had longer median PFS compared to cases where the most proximal PD-L1 was <1%. Among patients with multiple TMB assessments before ICI, patients with a TMB ≥10 mut/Mb based on the most recent assessment, as compared to those with a TMB <10 mut/Mb, achieved improved PFS and overall survival to ICI; instead, no differences were observed when patients were categorized using the oldest TMB assessment. CONCLUSIONS: Despite intrapatient concordance in PD-L1 and TMB, variation in these biomarkers can influence ICI outcomes, warranting consideration for reassessment before ICI initiation when feasible.
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Background: Women have smaller coronary size than men independent of body surface area. Female to male heart transplantation demonstrates coronary lumen enlargement. Purpose: To investigate relationships between endogenous androgens and coronary luminal size in women with suspected ischemic heart disease (IHD). Methods: We analyzed 69 women with available androgen levels. Results: Group mean age was 54 ± 10 years with 64 % post-menopausal. Lumen cross-sectional area (CSA) and external elastic membrane (EEM) CSA positively correlated with free testosterone (FT) (r = 0.29, p = 0.049; r = 0.29, p = 0.01), respectively, and negatively correlated with SHBG (r = -0.26, p = 0.03; r = -0.29, p = 0.02), respectively. Atheroma CSA positively correlated with FT (r = 0.24. p = 0.05). These correlations became non-significant after adjusting for waist circumference. Conclusions: In women with suspected ischemic heart disease, endogenous androgens, coronary atheroma and luminal size are related, and may be moderated by waist circumference.
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A gallium interstitial defect is thought to be responsible for the spectacular spin-dependent recombination in GaAs_{1-x}N_{x} dilute nitrides. Current understanding associates this defect with at least two in-gap levels corresponding to the (+/0) and (++/+) charge-state transitions. Using a spin-sensitive photoinduced current transient spectroscopy, the in-gap electronic structure of a x=0.021 alloy is revealed. The (+/0) state lies ≈0.27 eV below the conduction band edge, and an anomalous, negative activation energy reveals the presence of not one but two other in-gap states. The observations are consistent with a (++/+) state ≈0.19 eV above the valence band edge, and a (+++/++) state ≈25 meV above the valence band edge.
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A study of the dead layer thickness and quenching factor of a plastic scintillator for use in ultracold neutron (UCN) experiments is described. Alpha spectroscopy was used to determine the thickness of a thin surface dead layer to be 630 ± 110 nm. The relative light outputs from the decay of 241Am and Compton scattering of electrons were used to extract Birks' law coefficient, yielding a kB value of 0.087 ± 0.003 mm/MeV, consistent with some previous reports for other polystyrene-based scintillators. The results from these measurements are incorporated into the simulation to show that an energy threshold of (â¼9 keV) can be achieved for the UCNProBe experiment. This low threshold enables high beta particle detection efficiency and the indirect measurement of UCN. The ability to make the scintillator deuterated, accompanied by its relatively thin dead layer, gives rise to unique applications in a wide range of UCN experiments, where it can be used to trap UCN and detect charged particles in situ.
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Spin defects in silicon carbide are promising candidates for quantum sensing applications as they exhibit long coherence times even at room temperature. However, spin readout methods that rely on fluorescence detection can be challenging due to poor photon collection efficiency. Here, we demonstrate coherent spin control and all-electrical readout of a small ensemble of spins in a SiC junction diode using pulsed electrically detected magnetic resonance. A lock-in detection scheme based on a three stage modulation cycle is implemented, significantly enhancing the signal-to-noise ratio. This technique enabled observation of coherent spin dynamics, specifically Rabi spin nutation, spin dephasing, and spin decoherence. The use of these protocols for magnetometry applications is evaluated.
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INTRODUCTION: Exposure factor selection influences ionising radiation dose and image quality in projection radiography. Radiographers have a duty to comply with legislation, ensuring doses (resulting from exposure factor selection) are kept ALARP. Hence, this paper aims to explore variation in patient habitus perceptions among final-year student radiographers and any influence on imparted dose due to exposure factor selection. METHODS: Institutional ethics was granted. Student radiographers engaged in a 2-stage primary research study. Students were asked to select exposure factors (kVp and mAs values) and the most appropriate BMI category for several models undergoing a routine anteroposterior abdomen projection. Monte-Carlo simulation software was utilised to establish the absorbed and effective dose for these exposures. SPSS software was used to conduct statistical analysis of this data. RESULTS: A response rate of 19% (n = 14) was recorded. The findings identified variation in habitus perception with greater variation among female models. (p = 0.002). There was significant variation in exposure factor selection and ionising radiation dose, particularly between the male and female models. There was a significant difference between the healthy, overweight, and obese female models for absorbed (p = 0.032) and effective dose (p = 0.032) but not for the male models. CONCLUSION: There was a distinct difficulty recognising overweight and obese models and inconsistency regarding the selection of exposure factors. It was concluded that male models were more likely to receive a greater dose than females due to higher proposed exposure factors. IMPLICATIONS FOR PRACTICE: This study adds to the existing evidence base, providing insight into the perceptions of radiography students and the effect on exposure factor selection. This study will likely stand as a baseline for further investigation into competency levels among qualified radiographers to improve radiation protection.
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Dosis de Radiación , Humanos , Femenino , Masculino , Método de Montecarlo , Percepción , Índice de Masa CorporalRESUMEN
The American Veterinary Medical Association recognizes castration to be important for both human and animal safety. Lidocaine delivered through-the-needle has been shown to be effective at reducing cortisol response to castration, but this method has drawbacks for both animals and caretakers. As such, a study was conducted to examine the potential benefits of lidocaine delivery using a pneumatic needle-free device immediately before standing bovine castration. Twelve Holstein bulls weighing 400.7 ± 39.5 kg (mean ± standard deviation) were enrolled. Bulls were allocated to receive a local anesthetic block of 2% lidocaine for surgical castration by traditional needle injection or by needle-free injection. Outcomes were collected out to 48 h postcastration. Outcome variables included plasma cortisol concentrations, visual analog scale scores for pain, medial canthus temperatures as measured using infrared thermography, pressure mat changes, and chute defense scores. A time effect was observed for cortisol, visual analog scale scores, infrared thermography temperatures, and some pressure mat outcomes. No statistically significant differences between lidocaine delivery methods were observed, but further research is needed to build upon this small dataset.
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PURPOSE OF REVIEW: Cervical spine pain with or without radicular symptoms is a common condition leading to high utilization of the healthcare system with over 10 million medical visits per year. Many patients undergo surgical interventions and unfortunately are still left with neck and upper extremity pain, sometimes referred to as "Failed Neck Surgery Syndrome." When these options fail, cervical spinal cord stimulation can be a useful tool to decrease pain and suffering as well as reduce prescription medication use. RECENT FINDINGS: Spinal cord stimulation is a well-established therapy for chronic back and leg pain and is becoming more popular for neck and upper extremity pain. Recent studies have explored cervical spinal cord stimulation with successful outcomes regarding improved pain scores, functional outcomes, and reduction of prescription medication use. Continued research into cervical spinal cord stimulation is essential for maximizing its therapeutic potential for patients with chronic neck and upper extremity pain. This review highlights the importance of cervical spinal cord stimulation as an option for patients with failed neck surgery syndrome.
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Dolor de Cuello , Estimulación de la Médula Espinal , Humanos , Estimulación de la Médula Espinal/métodos , Dolor de Cuello/terapia , Vértebras Cervicales/cirugía , Insuficiencia del TratamientoRESUMEN
A high-spin nucleus coupled to a color center can act as a long-lived memory qudit in a spin-photon interface. The germanium vacancy (GeV) in diamond has attracted recent attention due to its excellent spectral properties and provides access to the ten-dimensional Hilbert space of the I=9/2 ^{73}Ge nucleus. Here, we observe the ^{73}GeV hyperfine structure, perform nuclear spin readout, and optically initialize the ^{73}Ge spin into any eigenstate on a µs timescale and with a fidelity of up to â¼84%. Our results establish ^{73}GeV as an optically addressable high-spin quantum platform for a high-efficiency spin-photon interface as well as for foundational quantum physics and metrology.
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We present the requirements, design, and evaluation of the cryogenic continuously rotating half-wave plate (CHWP) for the Simons Observatory (SO). SO is a cosmic microwave background polarization experiment at Parque Astronómico de Atacama in northern Chile that covers a wide range of angular scales using both small (â0.42 m) and large (â6 m) aperture telescopes. In particular, the small aperture telescopes (SATs) focus on large angular scales for primordial B-mode polarization. To this end, the SATs employ a CHWP to modulate the polarization of the incident light at 8 Hz, suppressing atmospheric 1/f noise and mitigating systematic uncertainties that would otherwise arise due to the differential response of detectors sensitive to orthogonal polarizations. The CHWP consists of a 505 mm diameter achromatic sapphire HWP and a cryogenic rotation mechanism, both of which are cooled down to â¼50 K to reduce detector thermal loading. Under normal operation, the HWP is suspended by a superconducting magnetic bearing and rotates with a constant 2 Hz frequency, controlled by an electromagnetic synchronous motor. We find that the number of superconductors and the number of magnets that make up the superconducting magnetic bearing are important design parameters, especially for the rotation mechanism's vibration performance. The rotation angle is detected through an angular encoder with a noise level of 0.07 µrad s. During a cooldown process, the rotor is held in place by a grip-and-release mechanism that serves as both an alignment device and a thermal path. In this paper, we provide an overview of the SO SAT CHWP: its requirements, hardware design, and laboratory performance.
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Using an 185-kg NaI[Tl] array, COHERENT has measured the inclusive electron-neutrino charged-current cross section on ^{127}I with pion decay-at-rest neutrinos produced by the Spallation Neutron Source at Oak Ridge National Laboratory. Iodine is one the heaviest targets for which low-energy (≤50 MeV) inelastic neutrino-nucleus processes have been measured, and this is the first measurement of its inclusive cross section. After a five-year detector exposure, COHERENT reports a flux-averaged cross section for electron neutrinos of 9.2_{-1.8}^{+2.1}×10^{-40} cm^{2}. This corresponds to a value that is â¼41% lower than predicted using the MARLEY event generator with a measured Gamow-Teller strength distribution. In addition, the observed visible spectrum from charged-current scattering on ^{127}I has been measured between 10 and 55 MeV, and the exclusive zero-neutron and one-or-more-neutron emission cross sections are measured to be 5.2_{-3.1}^{+3.4}×10^{-40} and 2.2_{-0.5}^{+0.4}×10^{-40} cm^{2}, respectively.
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PURPOSE OF REVIEW: Persistent spinal pain syndromes are pervasive and lead to functional impairment, increased healthcare utilization, potential disability, and high societal costs. Spinal (cervical, thoracic, lumbar, and sacroiliac joint) pain includes mechanical, degenerative, inflammatory, oncologic, and infectious etiologies. Regenerative medicine is a novel biotechnology targeting mechanical, degenerative, and inflammatory conditions believed to cause pain. Preparations including platelet-rich plasma, mesenchymal stem cells (adipose tissue and bone marrow aspirate concentrates), and growth factors are derived from an autologous donor. The goal of intervention through guided injection of the regenerative media is to reduce inflammation and reverse the degenerative cascade in hopes of restoring normal cellular composition (physiologic homeostasis) and anatomical function to improve pain and function. The authors review limited research supporting the use of platelet-rich plasma injections for facet joint arthropathy and sacroiliac joint pain compared to traditional steroid treatments, as well as the use of platelet rich plasma or mesenchymal stem cells for lumbar discogenic and radicular pain. RECENT FINDINGS: Current evidence to support regenerative medicine for spine-related pain is limited. Although several studies demonstrated a reduction in pain, many of these studies had a small number of participants and were case series or prospective trials. Regenerative medicine treatments lack evidence for the treatment of spine-related pain. Large randomized controlled trials are needed with consistent study protocols to make further recommendations.
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The objective of this study was to evaluate potency and timing of trenbolone acetate (TBA) administration on live performance and carcass characteristics of beefâ ×â dairy steers. A total of 6,895 beefâ ×â dairy steers [initial body weight (BW)â =â 157â ±â 5.2 kg] were allotted into 30 pens, with pen as the experimental unit. Each pen was randomly assigned one of three implant treatments: 1) Revalor-IS (IS) at d 0, IS at d 80, and Revalor-XS (XS) at d 160 (IS/IS/XS); 2) Ralgro at d 0, IS at d 80, and XS at d 160 (Ral/IS/XS); or 3) Encore at d 0 and XS at d 160 (Enc/XS). Steers were blocked by arrival date, each pen was terminally sorted in three ways at 257â ±â 22 days on feed and harvested at 329â ±â 25 days on feed. For live and carcass outcomes, fixed effect of implant treatment and random effect of block was evaluated. Data are reported on a deads and removals out basis. Removals, morbidity, and mortality were similar (Pâ ≥â 0.45). Steers administered TBA prior to d 160 were 5.8 kg heavier (Pâ =â 0.03) than Enc/XS steers at d 160. Final BW was not different (Pâ =â 0.78). Early administration of a TBA-containing implant resulted in an increased prevalence of bullers [2.40%, 5.18%, 6.86% (for Enc/XS, Ral/IS/XS, and IS/IS/XS) respectively; Pâ <â 0.01]. Dry matter intake (DMI) was 2.3% greater (Pâ <â 0.01) in steers administered Enc/XS compared to IS/IS/XS; however, DMI as a percentage of BW, average daily gain, and feed efficiency were not different (Pâ ≥â 0.12). Dressing percentage, hot carcass weight, heavy carcass occurrence, Longissimus muscle area, and 12th rib fat thickness were similar among all steers (Pâ ≥â 0.28). Marbling score tended to be greatest for Enc/XS and Ral/IS/XS (Pâ =â 0.09). Enc/XS graded a greater proportion of USDA Prime and fewer USDA Select carcasses than IS/IS/XS (Pâ <â 0.05). Enc/XS and Ral/IS/XS tended (Pâ =â 0.09) to have more USDA Yield Grade (YG) 1 carcasses. While delayed administration or decreased total potency of TBA-containing implants may decrease buller incidence and improve Quality Grade, few differences were observed in live or carcass outcomes.
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When humans begin learning new motor skills, they typically display early rapid performance improvements. It is not well understood how knowledge acquired during this early skill learning period generalizes to new, related skills. Here, we addressed this question by investigating factors influencing generalization of early learning from a skill A to a different, but related skill B. Early skill generalization was tested over four experiments (N = 2095). Subjects successively learned two related motor sequence skills (skills A and B) over different practice schedules. Skill A and B sequences shared ordinal (i.e., matching keypress locations), transitional (i.e., ordered keypress pairs), parsing rule (i.e., distinct sequence events like repeated keypresses that can be used as a breakpoint for segmenting the sequence into smaller units) structures, or possessed no structure similarities. Results showed generalization for shared parsing rule structure between skills A and B after only a single 10-second practice trial of skill A. Manipulating the initial practice exposure to skill A (1 to 12 trials) and inter-practice rest interval (0-30 s) between skills A and B had no impact on parsing rule structure generalization. Furthermore, this generalization was not explained by stronger sensorimotor mapping between individual keypress actions and their symbolic representations. In contrast, learning from skill A did not generalize to skill B during early learning when the sequences shared only ordinal or transitional structure features. These results document sequence structure that can be very rapidly generalized during initial learning to facilitate generalization of skill.
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Shape displays which actively manipulate surface geometry are an expanding robotics domain with applications to haptics, manufacturing, aerodynamics, and more. However, existing displays often lack high-fidelity shape morphing, high-speed deformation, and embedded state sensing, limiting their potential uses. Here, we demonstrate a multifunctional soft shape display driven by a 10 × 10 array of scalable cellular units which combine high-speed electrohydraulic soft actuation, magnetic-based sensing, and control circuitry. We report high-performance reversible shape morphing up to 50 Hz, sensing of surface deformations with 0.1 mm sensitivity and external forces with 50 mN sensitivity in each cell, which we demonstrate across a multitude of applications including user interaction, image display, sensing of object mass, and dynamic manipulation of solids and liquids. This work showcases the rich multifunctionality and high-performance capabilities that arise from tightly-integrating large numbers of electrohydraulic actuators, soft sensors, and controllers at a previously undemonstrated scale in soft robotics.
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OBJECTIVE: To describe the development, implementation, and validation of a radiology-administered protocol to obtain magnetic resonance imaging (MRI) in patients with cochlear implants and auditory brainstem implants without magnet removal. STUDY DESIGN: Retrospective review and description of novel care pathway. METHODS: A radiology-administered protocol was designed based on careful input from the radiology safety committee and neurotology. Radiology technologist training modules, consent instructions, patient educational material, clinical audits, and other safeguards were implemented, with samples provided in this report. The primary outcomes measured included instances of magnet displacement during MRI and premature termination of MRI studies secondary to pain. RESULTS: Between June 19, 2018, and October 12, 2021, 301 implanted ears underwent MRI without magnet removal, including 153 devices housing diametric MRI-conditional magnets, and 148 implants with conventional axial (i.e., nondiametric) magnets. Among cases with diametric MRI-conditional magnets, all studies were completed without magnet dislodgement or need to terminate imaging early due to pain. Among cases with conventional axial (nondiametric) magnets, 29 (19.6%) MRI studies were stopped prematurely secondary to pain or discomfort; the overall rate of this event was 9.6% (29 of 301) among the entire study cohort. In addition, 6.1% (9 of 148) experienced confirmed magnet displacement despite headwrap placement; the overall rate among all cases was 3.0% (9 of 301). Eight of these patients received successful external magnet reseating through manual pressure on the external scalp without surgery, and one required surgical replacement of the magnet in the operating room. There were no documented instances of hematoma, infection, device or magnet extrusion, internal device movement (i.e., gross receiver-stimulator migration), or device malfunction in this cohort related to MRI. CONCLUSIONS: We present the successful implementation of a radiology-administered protocol designed to streamline care for cochlear implant and auditory brainstem implant recipients who require MRI and ease clinical demands for otolaryngology providers. Examples of resources developed, including a process map, radiology training modules, consent instructions, patient educational materials, clinical audit, and other procedural safety measures are provided so interested groups may consider adapting and implementing related measures according to need.
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Implantación Coclear , Implantes Cocleares , Radiología , Humanos , Imanes , Flujo de Trabajo , Imagen por Resonancia Magnética/métodosRESUMEN
AIM: The purpose of this study was to explore whether grit is a predictor of success in associate degree nursing (ADN) programs. BACKGROUND: A question that challenges admission decision-making in nursing programs is "Who will succeed?" This question is particularly relevant in ADN programs, which often have higher attrition rates than baccalaureate programs. METHOD: This longitudinal, mixed-methods study was conducted with 451 ADN students across nine programs, including interviews with seven unsuccessful students and nine successful students. RESULTS: Short Grit Scale scores were not found to be statistically significant as a predictor of academic success; however, themes that emerged from the interviews do align with the theory of grit. CONCLUSION: Further research is needed to explore whether recognizing the level of grit in students during admission processes would help identify students who are likely to succeed.
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Health care workforce diversity is vital in combating health disparities. Despite much recent attention to downstream strategies to improve diversity in radiology, such as increased recruitment efforts and holistic application review, workforce diversity has not tangibly improved in recent decades. Yet, little discussion has been devoted to defining the obstacles that might delay, complicate, or altogether prevent persons from groups that have been traditionally marginalized and minoritized from a career in radiology. Refocusing attention to upstream barriers to medical education is vital to develop sustainable workforce diversity efforts in radiology. The purpose of this article is to highlight the varied obstacles students and trainees from historically underrepresented communities may face along the radiology career pathway and to provide concrete corollary programmatic solutions. Using a reparative justice framework, which encourages race- and gender-conscious repair of historical injustices, and the socioecological model, which recognizes an individual's choices are informed by historical and ongoing systems of power, this article advocates for tailored programs to improve justice, equity, diversity, and inclusion in radiology.