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Jamile A Ashmore,1,2 Anthony C Waddimba,2– 4 Megan E Douglas,5 Stacey V Coombes,6 Tait D Shanafelt,7 J Michael DiMaio2,4,8 1Office of Professionalism and Well-Being, Baylor Scott & White-The Heart Hospital, Plano, TX, USA; 2College of Medicine, Texas A&M University, Dallas, TX, USA; 3Division of Surgical Research, Department of Surgery, Baylor University Medical Center, Dallas, TX, USA; 4Research Development & Analytics Core, Baylor Scott and White Research Institute, Dallas, TX, USA; 5Trauma Research Consortium, Baylor Scott and White Research Institute, Dallas, TX, USA; 6OrganizationRx, Los Angeles, CA, USA; 7Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA; 8Division of Cardiothoracic Surgery, Baylor Scott & White-The Heart Hospital, Plano, TX, USACorrespondence: Jamile A Ashmore, Office of Professionalism and Well-being, Baylor Scott & White-The Heart Hospital, 1100 Allied Drive, Plano, TX, 75093, Tel +1469814-4289, Email Jamile.Ashmore@BSWHealth.orgImportance: Physician burnout has reached crisis levels. Supportive leadership is one of the strongest drivers of physician well-being, and monitoring supervisor support is key to developing well-being focused leadership skills. Existing measures of leader support were designed within “direct report” supervision structures limiting their applicability to matrixed leadership reporting structures where direct reports are not the predominant norm. Antecedently, no measure of leadership support is validated specifically for implementation in matrixed leadership structures.Objective: Adapt and validate the Mayo Leadership Impact Index (MLII) for settings with matrixed leadership structures.Design: A psychometric validation study utilizing classical test theory and item response theory.Setting: A tripartite hospital system in the southwestern US.Participants: Physician-respondents to a 2023 cross-sectional survey.Main Outcomes and Measures: After pilot testing, the adapted MLII was examined using a unidimensional graded response model and confirmatory factor analyses. Convergent validity was investigated via correlations with professional fulfillment, perceived autonomy support, self-valuation, and peer connectedness/respect. Divergent validity was tested via correlations with burnout.Results: Of the three candidate revisions of the MLII, the 9-item adaptation was selected for its superior validity/reliability indices. Standardized Cronbach’s and Ordinal alpha coefficients were 0.958 and 0.973, respectively. CFA loadings exceeded 0.70 (p < 0.001), and coefficients of variation (R2) exceeded 0.60 for all items. GRM slope parameters indicated “high” to “very high” item discrimination. Items 2, 5, and 8 were the most informative. Positive correlations of the adapted MLII with professional fulfillment, perceived autonomy support, and peer connectedness/respect were observed, supporting convergent validity. Negative correlation with overall burnout supports divergent validity.Conclusions and Relevance: The findings provide evidence of the adapted MLII’s validity, reliability, and appropriateness for implementation within matrixed leadership settings. Prior to this study, no leadership support measure had been validated for use among the growing number of healthcare systems with matrixed leadership reporting structures.Plain Language Summary: Question: What is the validity and reliability of a well-being centered leadership measure adapted for use in healthcare systems with matrixed, multiform reporting structures?Findings: Classical test theory and item response theory analyses of cross-sectional survey data from 158 physician-respondents supported the adapted measure’s construct validity. All reliability coefficients were strong. Leadership ratings positively correlated with professional fulfillment, autonomy support, self-valuation, and peer connectedness/respect, and negatively correlated with burnout.Meaning: Findings support the adapted measure’s validity and reliability. This study is the first to demonstrate a valid empirical measure of well-being centered leadership behaviors in settings with multiform, matrixed leadership structures.Keywords: physician, psychometrics, well-being, burnout, leader support

Key points Outer hair cells of the mammalian cochlea are cells which amplify the incoming sound using mechanisms based on prestin, a molecular actuator related to a family of chloride-bicarbonate exchangers., It has not been clear so far whether prestin has any bicarbonate-chloride exchange properties, often being described as an 'incomplete transporter'., Here we show, using a pH probe linked to prestin in an expression system, that prestin can transport bicarbonate at low rates and acts as an electrogenic transporter for chloride., The high expression level of prestin in mammalian outer hair cells thus accounts for a number of previous observations of the cells' internal pH regulation, and may indicate an additional role for prestin in homeostatic regulation of cochlear amplification., Abstract The lateral membrane of mammalian cochlear outer hair cells contains prestin, a protein which can act as a fast voltage-driven actuator responsible for electromotility and enhanced sensitivity to sound. The protein belongs to the SLC26 family of transporters whose members are characterised as able to exchange halides for SO42− or HCO3− yet previous analyses of mammalian prestin have suggested that such exchange functions were minimal. Here anion transport is investigated both in guinea-pig outer hair cells (OHCs) and in an expression system where we employ a sensitive intracellular pH (pHi) probe, pHluorin, to report HCO3− transport and to monitor the small pHi changes observable in the cells. In the presence of extracellular HCO3−, pHi recovered from an acid load 4 times faster in prestin-transfected cells. The acceleration required a chloride gradient established by reducing extracellular chloride to 2 m m. Similar results were also shown using BCECF as an alternative pHi sensor, but with recovery only found in those cells expressing prestin. Simultaneous electrophysiological recording of the transfected cells during bicarbonate exposure produced a shift in the reversal potential to more negative potentials, consistent with electrogenic transport. These data therefore suggest that prestin can act as a weak Cl−/HCO3− antiporter and it is proposed that, in addition to participating in wide band cochlear sound amplification, prestin may also be involved in the slow time scale (>10 s) phenomena where changes in cell stiffness and internal pressure have been implicated. The results show the importance of considering the effects of the endogenous bicarbonate buffering system in evaluating the function of prestin in cochlear outer hair cells. [ABSTRACT FROM AUTHOR]

Ultracold atoms can be manipulated using microfabricated devices known as atom chips. These have significant potential for applications in sensing, metrology, and quantum information processing. To date, the chips are loaded by transfer of atoms from an external macroscopic magnetooptical trap (MOT) into microscopic traps on the chip. This transfer involves a series of steps, which complicate the experimental procedure and lead to atom losses. In this paper, we present a design for integrating a MOT into a silicon wafer by combining a concave pyramidal mirror with a square wire loop. We describe how an array of such traps has been fabricated, and we present magnetic, thermal, and optical properties of the chip. [ABSTRACT FROM AUTHOR]

Objective: To describe doses of ionizing radiation and their possible associations with mortality rates and cancer incidence among Canadian dental workers. Methods: The National Dose Registry (NDR) of Canada was used to assess occupational dose of ionizing radiation received by dental workers. The NDR cohort includes 42,175 people classified as dental workers. Subjects in the NDR were linked to both the Canadian Mortality Database and the Canadian Cancer Database to ascertain cause of death and cancer incidence, respectively. Results: The cohort consisted of 9,051 male and 33,124 female dental workers. A total of 656 incident cases of cancer and 558 deaths were observed. The standardized mortality ratio associated with all-cause mortality was 0.53 (90% confidence interval [CI] 0.49-0.57). The incidence of cancer among dental workers was lower than that for the Canadian population ratio was 1.46 [90% CI 1.14-1.85]). Occupational doses of ionizing radiation among dentists and dental workers have decreased markedly since the 1950s. Conclusions: Dental workers receive very low doses of ionizing radiation, and these doses do not appear to be associated with any increase in cancer incidence; the increased incidence of melanoma is more likely related to other risk factors such as exposure to ultraviolet radiation from sunlight. [ABSTRACT FROM AUTHOR]