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.

Self-phase modulation and spectral broadening of optical pulses in semiconductor laser amplifiers

Abstract: Amplification of ultrashort optical pulses in semiconductor laser amplifiers is shown to result in considerable spectral broadening and distortion as a result of the nonlinear phenomenon of self-phase modulation (SPM). The physical mechanism behind SPM is gain saturation, which leads to intensity-dependent changes in the refractive index in response to variations in the carrier density. The effect of the shape and the initial frequency chirp of input pulses on the shape and the spectrum of amplified pulses is discussed in detail. Particular attention is paid to the case in which the input pulsewidth is comparable to the carrier lifetime so that the saturated gain has time to recover partially before the trailing edge of the pulse arrives. The experimental results, performed by using picosecond input pulses from a 1.52- mu m mode-locked semiconductor laser, are in agreement with the theory. When the amplified pulse is passed through a fiber, it is initially compressed because of the frequency chirp imposed on it by the amplifier. This feature can be used to compensate for fiber dispersion in optical communication systems. >

Nonsense-mediated mRNA decay: splicing, translation and mRNP dynamics

Abstract: Studies of nonsense-mediated mRNA decay in mammalian cells have proffered unforeseen insights into changes in mRNA–protein interactions throughout the lifetime of an mRNA. Remarkably, mRNA acquires a complex of proteins at each exon–exon junction during pre-mRNA splicing that influences the subsequent steps of mRNA translation and nonsense-mediated mRNA decay. Complex-loaded mRNA is thought to undergo a pioneer round of translation when still bound by cap-binding proteins CBP80 and CBP20 and poly(A)-binding protein 2. The acquisition and loss of mRNA-associated proteins accompanies the transition from the pioneer round to subsequent rounds of translation, and from translational competence to substrate for nonsense-mediated mRNA decay.

Inequality in quality : Addressing socioeconomic, racial, and ethnic disparities in health care

Abstract: Socioeconomic and racial/ethnic disparities in health care quality have been extensively documented. Recently, the elimination of disparities in health care has become the focus of a national initiative. Yet, there is little effort to monitor and address disparities in health care through organizational quality improvement. After reviewing literature on disparities in health care, we discuss the limitations in existing quality assessment for identifying and addressing these disparities. We propose 5 principles to address these disparities through modifications in quality performance measures: disparities represent a significant quality problem; current data collection efforts are inadequate to identify and address disparities; clinical performance measures should be stratified by race/ethnicity and socioeconomic position for public reporting; population-wide monitoring should incorporate adjustment for race/ethnicity and socioeconomic position; and strategies to adjust payment for race/ethnicity and socioeconomic position should be considered to reflect the known effects of both on morbidity. JAMA. 2000;283:2579-2584

Lenalidomide in the myelodysplastic syndrome with chromosome 5q deletion.

Abstract: Background Severe, often refractory anemia is characteristic of the myelodysplastic syndrome associated with chromosome 5q31 deletion. We investigated whether lenalidomide (CC5013) could reduce the transfusion requirement and suppress the abnormal 5q31− clone in patients with this disorder. Methods One hundred forty-eight patients received 10 mg of lenalidomide for 21 days every 4 weeks or daily. Hematologic, bone marrow, and cytogenetic changes were assessed after 24 weeks of treatment by an intention-to-treat analysis. Results Among the 148 patients, 112 had a reduced need for transfusions (76%; 95% confidence interval [CI], 68 to 82) and 99 patients (67%; 95% CI, 59 to 74) no longer required transfusions, regardless of the karyotype complexity. The response to lenalidomide was rapid (median time to response, 4.6 weeks; range, 1 to 49) and sustained; the median duration of transfusion independence had not been reached after a median of 104 weeks of follow-up. The maximum hemoglobin concentration reached...