University of Rochester

About: University of Rochester is a education organization based out in Rochester, New York, United States. It is known for research contribution in the topics: Population & Laser. The organization has 63915 authors who have published 112762 publications receiving 5484122 citations. The organization is also known as: Rochester University.

Predictions for the rates of compact binary coalescences observable by ground-based gravitational-wave detectors

Abstract: We present an up-to-date, comprehensive summary of the rates for all types of compact binary coalescence sources detectable by the initial and advanced versions of the ground-based gravitational-wave detectors LIGO and Virgo. Astrophysical estimates for compact-binary coalescence rates depend on a number of assumptions and unknown model parameters and are still uncertain. The most confident among these estimates are the rate predictions for coalescing binary neutron stars which are based on extrapolations from observed binary pulsars in our galaxy. These yield a likely coalescence rate of 100 Myr−1 per Milky Way Equivalent Galaxy (MWEG), although the rate could plausibly range from 1 Myr−1 MWEG−1 to 1000 Myr−1 MWEG−1 (Kalogera et al 2004 Astrophys. J. 601 L179; Kalogera et al 2004 Astrophys. J. 614 L137 (erratum)). We convert coalescence rates into detection rates based on data from the LIGO S5 and Virgo VSR2 science runs and projected sensitivities for our advanced detectors. Using the detector sensitivities derived from these data, we find a likely detection rate of 0.02 per year for Initial LIGO–Virgo interferometers, with a plausible range between 2 × 10−4 and 0.2 per year. The likely binary neutron–star detection rate for the Advanced LIGO–Virgo network increases to 40 events per year, with a range between 0.4 and 400 per year.

Increased production of reactive oxygen species in hyperglycemic conditions requires dynamic change of mitochondrial morphology

Abstract: Increased production of mitochondrial reactive oxygen species (ROS) by hyperglycemia is recognized as a major cause of the clinical complications associated with diabetes and obesity [Brownlee, M. (2001) Nature 414, 813–820]. We observed that dynamic changes in mitochondrial morphology are associated with high glucose-induced overproduction of ROS. Mitochondria undergo rapid fragmentation with a concomitant increase in ROS formation after exposure to high glucose concentrations. Neither ROS increase nor mitochondrial fragmentation was observed after incubation of cells with the nonmetabolizable stereoisomer l-glucose. However, inhibition of mitochondrial pyruvate uptake that blocked ROS increase did not prevent mitochondrial fragmentation in high glucose conditions. Importantly, we found that mitochondrial fragmentation mediated by the fission process is a necessary component for high glucose-induced respiration increase and ROS overproduction. Extended exposure to high glucose conditions, which may mimic untreated diabetic conditions, provoked a periodic and prolonged increase in ROS production concomitant with mitochondrial morphology change. Inhibition of mitochondrial fission prevented periodic fluctuation of ROS production during high glucose exposure. These results indicate that the dynamic change of mitochondrial morphology in high glucose conditions contributes to ROS overproduction and that mitochondrial fission/fusion machinery can be a previously unrecognized target to control acute and chronic production of ROS in hyperglycemia-associated disorders.

On the measurement of achievement goals: critique, illustration, and application

Abstract: The authors identified several specific problems with the measurement of achievement goals in the current literature and illustrated these problems, focusing primarily on A. J. Elliot and H. A. McGregor's (2001) Achievement Goal Questionnaire (AGQ). They attended to these problems by creating the AGQ-Revised and conducting a study that examined the measure's structural validity and predictive utility with 229 (76 male, 150 female, 3 unspecified) undergraduates. The hypothesized factor and dimensional structures of the measure were confirmed and shown to be superior to a host of alternatives. The predictions were nearly uniformly supported with regard to both the antecedents (need for achievement and fear of failure) and consequences (intrinsic motivation and exam performance) of the 4 achievement goals. In discussing their work, the authors highlight the importance and value of additional precision in the area of achievement goal measurement.

Emerging Market Business Cycles: The Cycle is the Trend

Abstract: Emerging market business cycles exhibit strongly countercyclical current accounts, consumption volatility that exceeds income volatility, and “sudden stops” in capital inflows. These features contrast with developed small open economies. Nevertheless, we show that a standard model characterizes both types of markets. Motivated by the frequent policy regime switches observed in emerging markets, our premise is that these economies are subject to substantial volatility in trend growth. Our methodology exploits the information in consumption and net exports to identify the persistence of productivity. We find that shocks to trend growth—rather than transitory fluctuations around a stable trend—are the primary source of fluctuations in emerging markets. The key features of emerging market business cycles are then shown to be consistent with this underlying income process in an otherwise standard equilibrium model.

The effect of emergency department crowding on clinically oriented outcomes

Abstract: Background: An Institute of Medicine (IOM) report defines six domains of quality of care: safety, patient-centeredness, timeliness, efficiency, effectiveness, and equity. The effect of emergency department (ED) crowding on these domains of quality has not been comprehensively evaluated. Objectives: The objective was to review the medical literature addressing the effects of ED crowding on clinically oriented outcomes (COOs). Methods: We reviewed the English-language literature for the years 1989–2007 for case series, cohort studies, and clinical trials addressing crowding’s effects on COOs. Keywords searched included “ED crowding,”“ED overcrowding,”“mortality,”“time to treatment,”“patient satisfaction,”“quality of care,” and others. Results: A total of 369 articles were identified, of which 41 were kept for inclusion. Study quality was modest; most articles reflected observational work performed at a single institution. There were no randomized controlled trials. ED crowding is associated with an increased risk of in-hospital mortality, longer times to treatment for patients with pneumonia or acute pain, and a higher probability of leaving the ED against medical advice or without being seen. Crowding is not associated with delays in reperfusion for patients with ST-elevation myocardial infarction. Insufficient data were available to draw conclusions on crowding’s effects on patient satisfaction and other quality endpoints. Conclusions: A growing body of data suggests that ED crowding is associated both with objective clinical endpoints, such as mortality, as well as clinically important processes of care, such as time to treatment for patients with time-sensitive conditions such as pneumonia. At least two domains of quality of care, safety and timeliness, are compromised by ED crowding.