Evaluating Urology Program Directors' Perception on Resident Application Parameters Following the Transition of USMLE Step 1 to Pass/Fail.

OBJECTIVE: To investigate how the shift of the United States Medical Licensing Examination (USMLE) Step 1 to a Pass/Fail (P/F) scoring system impacts the perceptions of Urology Program Directors (PDs) on evaluating urology residency applicants. METHODS AND MATERIALS: A cross-sectional survey was sent to 117 PDs, including questions about program characteristics, perceptions of shelf scores and medical school rank post-transition, beliefs about the predictive value of Step 1 and Step 2 Clinical Knowledge (CK) scores for board success and residency performance, and changes in applicant parameter ranking. RESULTS: Forty-five PDs (38% response rate) participated. Notably, 49% favored releasing quantitative clerkship grades, and 71% valued medical school rank more. Opinions on Step 1 scores' correlation with board success were split (49% agreed), and 44% endorsed Step 2 CK scores' connection to board performance. As predictors of good residents, only 9% and 22% considered Step 1 and Step 2 CK scores, respectively, indicative. Clerkship grades and Urology rotation recommendation letters maintained significance, while research experience gained importance. Step 2 CK scores' importance rose but did not match Step 1 scores' previous significance. CONCLUSION: The transition to P/F for USMLE Step 1 adds intricacies to urology residency selection, exposing PDs' uncertainties regarding clerkship grades and the relevance of medical school rank. This research underscores the dynamic nature of urology residency admissions, emphasizing the increasing importance of research in evaluating applicants and a diminishing emphasis on volunteering and leadership.

Hydrogen peroxide treatment promotes chlorophytes over toxic cyanobacteria in a hyper-eutrophic aquaculture pond.

Controlling blooms of toxigenic phytoplankton, including cyanobacteria, is a high priority for managers of aquatic systems that are used for drinking water, recreation, and aquaculture production. Although a variety of treatment approaches exist, hydrogen peroxide (H2O2) has the potential to be an effective and ecofriendly algaecide given that this compound may select against cyanobacteria while not producing harmful residues. To broadly evaluate the effectiveness of H2O2 on toxigenic phytoplankton, we tested multiple concentrations of H2O2 on (1) four cyanobacterial cultures, including filamentous Anabaena, Cylindrospermopsis, and Planktothrix, and unicellular Microcystis, in a 5-day laboratory experiment and (2) a dense cyanobacterial bloom in a 7-day field experiment conducted in a nutrient-rich aquaculture pond. In the laboratory experiment, half-maximal effective concentrations (EC50) were similar for Anabaena, Cylindrospermopsis, and Planktothrix (average EC50 = 0.41 mg L-1) but were ∼10x lower than observed for Microcystis (EC50 = 5.06 mg L-1). Results from a field experiment in an aquaculture pond showed that ≥1.3 and ≥ 6.7 mg L-1 of H2O2 effectively eliminated Planktothrix and Microcystis, respectively. Moreover, 6.7 mg L-1 of H2O2 reduced microcystin and enhanced phytoplankton diversity, while causing relatively small negative effects on zooplankton abundance. In contrast, 20 mg L-1 of H2O2 showed the greatest negative effect on zooplankton. Our results demonstrate that H2O2 can be an effective, rapid algaecide for controlling toxigenic cyanobacteria when properly dosed.