Even in healthy aging, cardiac morbidity and mortality increase with age in both mice and humans. These effects include a decline in diastolic function, left ventricular hypertrophy, metabolic substrate shifts, and alterations in the cardiac proteome.Previous work from our laboratory indicated that short-term (10-week) treatment with rapamycin, an mTORC1 inhibitor, improved measures of these age-related changes. In this report, we demonstrate that the rapamycin-dependent improvement of diastolic function is highly persistent, while decreases in both cardiac hypertrophy and passive stiffness are substantially persistent 8 weeks after cessation of an 8-week treatment of rapamycin in both male and female 22-to 24-month-old C57BL/6NIA mice. The proteomic and metabolomic abundance changes that occur after 8 weeks of rapamycin treatment have varying persistence after 8 further weeks without the drug. However, rapamycin did lead to a persistent increase in abundance of electron transport chain (ETC) complex components, most of which belonged to Complex I. Although ETC protein abundance and Complex I activity were each differentially affected in males and females, the ratio of Complex I activity to Complex I protein abundance was equally and persistently reduced after rapamycin treatment in both sexes. Thus, rapamycin treatment in the aged mice persistently improved diastolic function and myocardial stiffness, persistently altered the cardiac proteome in the absence of persistent metabolic changes, and led to persistent alterations in mitochondrial respiratory chain activity. These observations suggest that an optimal translational regimen for rapamycin therapy that promotes enhancement of healthspan may involve intermittent short-term treatments.

Hundreds of thousands of students drop out of school each year in the United States, despite billions of dollars of funding and myriad educational reforms. Existing research tends to look at the effect of easily measurable student characteristics. However, a vast number of harder-to-measure student traits, skills, and resources affect educational success. We present a conceptual framework for the cumulative effect of all factors, which we call student capital. We develop a method for estimating student capital in groups of students and find that student capital is distributed exponentially in each of 140 cohorts of community college students. Students’ ability to be successful does not behave like standard tests of intelligence. Instead, it acts like a limited resource, distributed unequally. The results suggest that rather than removing barriers related to easily measured characteristics, interventions should be focused on building up the skills and resources needed to be successful in school.

Objective: Remedial mathematics courses are widely considered a barrier to student success in community college, and there has been a significant amount of work recently to reform them. Yet, there is little research that explicitly examines whether increasing learning in remedial classes improves grades or completion rates. This study examines the relationship between procedural and conceptual learning in developmental math and measures of progress toward a degree, such as grades. Method: A mathematical skills assessment was given to all intermediate algebra students at a large, urban community college, and to students in the following collegelevel class at the beginning of the next term. Assessment scores were compared with student characteristics, grades in intermediate algebra, grades in college-level math, and whether the student earned a credential. Results: After controlling for grades in previous classes, procedural algebra skills were not associated with higher grades in college-level math. Conceptual mathematics proficiency was associated with higher grades in general education math but not in precalculus. In developmental classes, however, learning gains were primarily procedural, which were correlated with grades. In addition, students who took at least one term off of math had significantly lower procedural skills but not conceptual skills. Contributions: The findings challenge the assumption in community college research that increased student learning in remedial mathematics will improve student outcomes. The results suggest that the type of mathematics taught in developmental classes can have an effect on student outcomes. Instruction focused on procedural skills may not be preparing students for college mathematics.

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Objective: This study evaluates the postgraduate earnings of students with an applied baccalaureate (AB) degree compared to the earnings of students with the same associate degree but no baccalaureate degree. The research questions include the following: For those students who earn an AB degree, does it result in higher earnings than the associate degree? Does the earnings difference vary by field of study? Which student characteristics account for variation in earnings beyond the effect of the AB degree? Method: This study used propensity score weighted regression to examine the difference in earnings of AB degree and associate degree graduates in three programs—health, technology, and social science—at three different community and technical colleges in Washington state. Results: We find that the AB degree graduates have higher earnings than associate degree graduates in each of the three programs, although for certain programs the earnings increase is small enough to be explained by characteristics intrinsic to the student. Higher earnings are also associated to other student characteristics such as age, gender, earnings prior to enrollment, and academic proficiency, indicating a difference in economic benefit for some students. Contributions: The findings from this study contribute to the overall understanding of the complex relationship between level of education and earnings, specifically the impact on earnings of an AB above and beyond the associate degree. The analyses revealed evidence of a gender gap in earnings by program, which is an area that requires further study.