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.

Dust mite allergens and asthma—A worldwide problem

Abstract: Cette etude generale aborde successivement l'epidemiologie, l'entomologie (taxonomie, physiologie, biologie et ecologie des acariens), les allergenes des acariens (identification et standardisation), la methodologie de l'evaluation des acariens, la methodologie pour la collecte et le traitement des echantillons de poussieres, la lutte contre les acariens

The evolutionary dynamics of complex polymorphisms.

Abstract: The theory of balanced polymorphism which has been elaborated by population geneticists, notably Sewall Wright and R. A. Fisher, has in the main been concerned with the effects of single loci. As theory generally goes apace with experiment, this accent on single locus polymorphisms has been due to the plethora of observational evidence relating to simple cases. It is sufficient to note the vast effort made by Dobzhansky and his co-workers in their elucidation of the inversion polymorphism of the third chromosome of Drosophila pseudoobscura. In recent years, however, a few cases have come to light of polymorphisms involving more than one Mendelian unit. Among these are the inversions on different chromosomes found in D. robustca studied by Levitan (1955 and 1958), the shell color of Cepaea nemoralis reported by Lamotte (1951) and by Cain and Sheppard (1952), the complex mimicry pattern in certain butterflies (Sheppard, 1959) and the inversions in two chromosomes of the grasshopper Moraba scurra analyzed by White (1957) and Lewontin and White (1960). The study of effects of natural selection on single locus polymorphisms must take into account only inter-allelic effects such as additivity and dominance. In multi-locus polymorphisms, however,

Estimation of the number of alpha-helical and beta-strand segments in proteins using circular dichroism spectroscopy.

Abstract: A simple approach to estimate the number of alpha-helical and beta-strand segments from protein circular dichroism spectra is described. The alpha-helix and beta-sheet conformations in globular protein structures, assigned by DSSP and STRIDE algorithms, were divided into regular and distorted fractions by considering a certain number of terminal residues in a given alpha-helix or beta-strand segment to be distorted. The resulting secondary structure fractions for 29 reference proteins were used in the analyses of circular dichroism spectra by the SELCON method. From the performance indices of the analyses, we determined that, on an average, four residues per alpha-helix and two residues per beta-strand may be considered distorted in proteins. The number of alpha-helical and beta-strand segments and their average length in a given protein were estimated from the fraction of distorted alpha-helix and beta-strand conformations determined from the analysis of circular dichroism spectra. The statistical test for the reference protein set shows the high reliability of such a classification of protein secondary structure. The method was used to analyze the circular dichroism spectra of four additional proteins and the predicted structural characteristics agree with the crystal structure data.

Accurate SHAPE-directed RNA structure determination

Abstract: Almost all RNAs can fold to form extensive base-paired secondary structures. Many of these structures then modulate numerous fundamental elements of gene expression. Deducing these structure–function relationships requires that it be possible to predict RNA secondary structures accurately. However, RNA secondary structure prediction for large RNAs, such that a single predicted structure for a single sequence reliably represents the correct structure, has remained an unsolved problem. Here, we demonstrate that quantitative, nucleotide-resolution information from a SHAPE experiment can be interpreted as a pseudo-free energy change term and used to determine RNA secondary structure with high accuracy. Free energy minimization, by using SHAPE pseudo-free energies, in conjunction with nearest neighbor parameters, predicts the secondary structure of deproteinized Escherichia coli 16S rRNA (>1,300 nt) and a set of smaller RNAs (75–155 nt) with accuracies of up to 96–100%, which are comparable to the best accuracies achievable by comparative sequence analysis.