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Rationale: Stable carbon and oxygen isotope data of biogenic and abiogenic aragonite are of fundamental relevance in paleoclimate research. Wet-chemical analysis of such materials requires well-homogenized, fine-grained powder. In the present study, the effect of different grinding/milling methods on sample homogeneity and the potential risk of unintentional calcite formation and isotope shift were evaluated., Methods: Shells of Arctica islandica and aragonite sputnik crystals were pulverized using a set of commonly used methods, including a hand-held drill, a vibromill operated at various settings (with and without liquid nitrogen cooling, changes in ball diameters, frequencies, and processing durations), and an agate mortar and pestle. Stable isotope values were measured using an isotope ratio mass spectrometer operated in continuous flow mode. Identification of mineral phases was obtained by powder X-ray diffraction (PXRD), Raman spectroscopy, and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. Calcite content was quantified by PXRD Rietveld refinement., Results: Samples showed substantial homogeneity, in particular after vibromilling (duration 3-10 min). More vigorous grinding resulted in larger fractions of calcite (0.5-4.2 wt%) and a concomitant δ 18 O and δ 13 C decrease, specifically in bivalve shells. The only method for producing pure aragonite powder was by pounding the aragonite sputniks manually with an agate mortar and pestle., Conclusions: None of the studied, commonly used machine-based pulverization methods produced pure aragonite powder from samples consisting originally of aragonite. These findings have significant implications for light-stable isotope-based paleoclimate reconstructions. Except for abiogenic aragonite powder produced by pounding in an agate mortar, paleotemperatures would be overestimated., (© 2024 The Author(s). Rapid Communications in Mass Spectrometry published by John Wiley & Sons Ltd.)

Phenomenon: With the proliferation of pass/fail grading practices in the pre-clerkship phase of undergraduate medical education, questions arise about the transparency and variability of grading and grade reporting practices, raising issues of equity in assessment, particularly regarding residency matching. The purpose of this survey was to determine the remediation and academic performance reporting practices of United States (U.S.) allopathic medical schools in the pre-clerkship phase of their curricula. Approach: After an extensive literature search and feedback from curriculum deans and learning experts, we developed a survey that we sent in the Spring of 2022 to pre-clerkship curriculum officials at all 154 accredited U.S. allopathic medical schools. It addressed curriculum content and structure; pre-clerkship remediation (e.g., course retakes) and reporting (e.g., permanency of transcript notation) practices; documentation and reporting of nonacademic competencies; and participant opinions and recommendations regarding reporting, transparency, and equity. We generated descriptive statistics and did manifest coding of open-ended responses. Findings: We had a response rate of 40% (62/155), with over 71% indicating mainly organ systems-based curricula. Depending on the situation, there were a wide range of remediation approaches for single- and multiple-course failures, including tutoring or learning support, re-exams, and referrals to a promotion board. Professionalism concerns were a top priority to report to residency directors, with significant variability in respondent opinions and practices in reporting remedial activities. Respondents were concerned about equity, both in terms of flexible grading practices and transparency of reporting practices. Insights: The variability in reporting practices across schools, while allowing holistic and individualized approaches to academic support, also creates potential inequities. More work is needed to understand how different reporting practices across institutions may disadvantage marginalized and minoritized student groups at different points in their preparation.

Binary expression systems like the LexA-LexAop system provide a powerful experimental tool kit to study gene and tissue function in developmental biology, neurobiology, and physiology. However, the number of well-defined LexA enhancer trap insertions remains limited. In this study, we present the molecular characterization and initial tissue expression analysis of nearly 100 novel StanEx LexA enhancer traps, derived from the StanEx 1 index line. This includes 76 insertions into novel, distinct gene loci not previously associated with enhancer traps or targeted LexA constructs. Additionally, our studies revealed evidence for selective transposase-dependent replacement of a previously-undetected KP element on chromosome III within the StanEx 1 genetic background during hybrid dysgenesis, suggesting a molecular basis for the over-representation of LexA insertions at the NK7.1 locus in our screen. Production and characterization of novel fly lines were performed by students and teachers in experiment-based genetics classes within a geographically diverse network of public and independent high schools. Thus, unique partnerships between secondary schools and university-based programs have produced and characterized novel genetic and molecular resources in Drosophila for open-source distribution, and provide paradigms for development of science education through experience-based pedagogy., (Copyright © 2019 Kockel et al.)

Two young Labrador retriever dogs with bradycardia-induced syncope resulting from atrial myopathy underwent permanent transvenous pacemaker implantation. Both dogs developed heart failure 3-5 years after pacemaker implantation. Both were managed medically for approximately 7 years after pacemaker implantation and, ultimately, were humanely euthanized due to refractory heart failure signs and quality of life concerns. Long-term management of dogs with atrial myopathy and secondary atrial standstill with pacemaker implantation and medical therapy for heart failure is feasible and prognosis may be better than previously reported or speculated., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Renin-angiotensin system inhibitor (RASi) agents improve renal and cardiovascular outcomes in patients with diabetes mellitus (DM) and chronic kidney disease (CKD). Studies examining conformity to guidelines have relied on pharmacy claims or filled prescriptions rather than provider-based information. The main outcome of RASi use was examined in 2889 patients with CKD and DM for its association with patient characteristics and specialty clinic visits. RASi use was 77% during the 2-year study period, and declined with worsening CKD stages (79%, 59%, and 48% in stages III, IV, and V, respectively; P<.0001). By multivariate analysis, hypertension (odds ratio [OR], 5.49, 95% confidence interval [CI], 4.16-7.25); older age (OR, 0.85; 95% CI, 0.78-0.93), and higher glomerular filtration rate (OR, 1.42; 95% CI, 1.31-1.53) were associated with RASi use. In a model examining the effect of each specialty, RASi use was greater in patients attending cardiology (OR, 3.52; 95% CI, 2.63-4.71), pharmacy (OR, 3.15; 95% CI, 2.49-3.98), endocrine (OR, 3.39; 95% CI, 2.22-5.16), and renal clinic visits (OR, 2.04; 95% CI, 1.54-2.71). Diagnosis of hypertension increases RASi usage, whereas older age and lower glomerular filtration rate reduce that likelihood. Appropriate specialty referrals improve conformity to guidelines in practice., (© 2011 Wiley Periodicals, Inc.)

Background: hypertension is a modifiable risk factor in chronic kidney disease (CKD), and medication adherence (MA) is critical in reaching the treatment goals. Patterns of MA for antihypertensive agents and its impact on blood pressure (BP) in CKD practice settings are not well studied., Methods: we examined 7,227 CKD patients receiving at least one antihypertensive prescription between 2006 and 2007. Outpatient BP measurements were averaged as high (>130/ 80 mm Hg) versus normal (others). MA was calculated using medication possession ratio (MPR = actual treatment days/total possible treatment days). Good versus Poor MA (MPR ≥ 0.8 vs. <0.8) groups were compared for differences in demographic, co-morbid, and laboratory variables. The relationship between MA and BP was examined by logistic regression., Results: 4,867/7,227 patients (67%) had Good MA; the frequency of patients with Good MA varied by each drug class (p < 0.0001). MPR declined with worsening CKD (stage III: MPR = 0.83 standard deviation (SD 0.18); stage IV: MPR = 0.78 (SD 0.22); stage V: MPR = 0.75 (SD 0.21); p < 0.0001). Hospitalization episodes also negatively impacted adherence. Only 35% of CKD patients had normal BP. By multivariate analysis, Poor MA was associated with high BP (odds ratio 1.23, 95% confidence interval 1.11-1.37)., Conclusions: 33% of CKD patients have Poor MA for antihypertensive agents, and MA worsens with declining renal function. Poor MA is associated with a 23% greater risk of uncontrolled hypertension. Monitoring and improving adherence in CKD practice may improve outcomes., (2010 S. Karger AG, Basel.)