College Campus Sexual Assault and Retention Rates

Increased media attention on college crime, specifically sexual assault, has led to greater prioritization of campus safety when deciding whether to continue attending a college. This, coupled with society’s view of a four-year college education as a necessity to succeed in the labor market, creates a potential tradeoff between safety on campus and future employment success. To analyze such tradeoff, I use data from the US Department of Education from 2014 to 2017 to examine whether college campus sexual assault at four-year American institutions impacts retention rates. Such results have implications for college policies to combat sexual assault on campus not only to keep students safe, but to prevent students from transferring or dropping out which could curb institutional money flow. Using an OLS model that addresses typical difficulties associated with time series work, I find that college campus sexual assault decreases retention rates at a statistically significant level, implying that college students value their safety at school more than any potential change in their future job market success due to transferring or dropping out

College Crime and Retention Rates

Increased media attention on college crime has led to greater prioritization of campus safety when selecting a college to attend. This, coupled with society’s view of higher education as a necessity to succeed in the labor market, creates a potential tradeoff between safety on campus and future job success. To analyze such tradeoff, I examine whether college crime affects retention rates at four-year American institutions. While literature has focused on college crime and factors that affect the decision to begin attending a college, no study has solely focused on the college crime and the decision to continue attending a college. Using data from the US Department of Education, I estimate the effect of college crime and changing college crime expectations on retention rates from 2009 to 2016 for four-year institutions using linear and nonlinear OLS regressions. Such results have implications for college policies to combat crime on campus not only to keep students safe, but to prevent students from transferring or dropping out. Using an instrumental regression with a proxy for average state temperature, along with fixed effects and interaction terms, I find that college crime expectations and college crime overall have a negative, statistically insignificant effect on retention rates

Guidelines: The do's, don'ts and don't knows of direct observation of clinical skills in medical education.

IntroductionDirect observation of clinical skills is a key assessment strategy in competency-based medical education. The guidelines presented in this paper synthesize the literature on direct observation of clinical skills. The goal is to provide a practical list of Do's, Don'ts and Don't Knows about direct observation for supervisors who teach learners in the clinical setting and for educational leaders who are responsible for clinical training programs.MethodsWe built consensus through an iterative approach in which each author, based on their medical education and research knowledge and expertise, independently developed a list of Do's, Don'ts, and Don't Knows about direct observation of clinical skills. Lists were compiled, discussed and revised. We then sought and compiled evidence to support each guideline and determine the strength of each guideline.ResultsA final set of 33 Do's, Don'ts and Don't Knows is presented along with a summary of evidence for each guideline. Guidelines focus on two groups: individual supervisors and the educational leaders responsible for clinical training programs. Guidelines address recommendations for how to focus direct observation, select an assessment tool, promote high quality assessments, conduct rater training, and create a learning culture conducive to direct observation.ConclusionsHigh frequency, high quality direct observation of clinical skills can be challenging. These guidelines offer important evidence-based Do's and Don'ts that can help improve the frequency and quality of direct observation. Improving direct observation requires focus not just on individual supervisors and their learners, but also on the organizations and cultures in which they work and train. Additional research to address the Don't Knows can help educators realize the full potential of direct observation in competency-based education

Directed evolution of Vibrio fischeri LuxR for improved response to butanoyl-homoserine lactone

LuxR is the 3-oxohexanoyl-homoserine lactone (3OC6HSL) dependent transcriptional activator of the prototypical acyl-homoserine lactone (AHL) quorum sensing system of Vibrio fischeri. Wild-type LuxR exhibits no response to butanoyl-HSL (C4HSL) in quantitative bioassays at concentrations of up to 1 µM; a previously described LuxR variant (LuxR-G2E) exhibits a broadened response to diverse AHLs, including pentanoyl-HSL (C5HSL), but not to C4HSL. Here, two rounds of directed evolution of LuxR-G2E generated variants of LuxR that responded to C4HSL at concentrations as low as 10 nM. One variant, LuxR-G4E, had only one change, I45F, relative to the parent LuxR-G2E, which itself differs from wild-type at three residues. Dissection of the four mutations within LuxR-G4E demonstrated that at least three of these changes were simultaneously required to achieve any measurable C4HSL response. The four changes improved both sensitivity and specificity towards C4HSL relative to any of the other 14 possible combinations of those residues. These data confirm that LuxR is evolutionarily pliable and suggest that LuxR is not intrinsically asymmetric in its response to quorum sensing signals with different acyl-side chain lengths

Nanoscale Torsional Optomechanics

Optomechanical transduction is demonstrated for nanoscale torsional resonators evanescently coupled to optical microdisk whispering gallery mode resonators. The on-chip, integrated devices are measured using a fully fiber-based system, including a tapered and dimpled optical fiber probe. With a thermomechanically calibrated optomechanical noise floor down to 7 fm/sqrt(Hz), these devices open the door for a wide range of physical measurements involving extremely small torques, as little as 4x10^-20 N*m.Comment: 4 pages, 4 figures - Accepted to APL Oct 22nd, 2012. To appear in February 4th issue - as cover articl