21,797 research outputs found
Recommended from our members
Estimators for QST and coalescence times.
Comparisons of QST to FST can provide insights into the evolutionary processes that lead to differentiation, or lack thereof, among the phenotypes of different groups (e.g., populations, species), and these comparisons have been performed on a variety of taxa, including humans. Here, I show that for neutrally evolving (i.e., by genetic drift, mutation, and gene flow alone) quantitative characters, the two commonly used QST estimators have somewhat different interpretations in terms of coalescence times, particularly when the number of groups that have been sampled is small. A similar situation occurs for FST estimators. Consequently, when observations come from only a small number of groups, which is not an unusual situation, it is important to match estimators appropriately when comparing QST to FST
Oregon Mathematics Leadership Institute Project: Evaluation Results on Teacher Content Knowledge, Implementation Fidelity, and Student Achievement
The Oregon Mathematics Leadership Institute (OMLl) National Science Foundation Mathematics and Science Partnership project partners are Oregon State University, Portland State University, Teachers Development Group, and ten Oregon school districts. The primary activities of the project were a sequence of three intensive three-week residential institutes emphasizing mathematics content knowledge for teaching, collegial leadership, and the building of Professional Learning Communities. Teachers at all levels of grades K-12 participated together in the mathematics content courses. By the conclusion of the. third Summer Institute, teachers had shown signiïŹcant improvements in mathematical content knowledge for teaching. Analysis of student achievement data in participating schools was initially inconclusive. However, once implementation fidelity traits were taken into account, a positive relationship between project participation and student achievement emerged. The degree to which schools implement the practices promoted by the OMLI project is a significant positive predictor of student perfomiance above and beyond what can be explained by the socioeconomic factor as indicated by the percentage of students who qualify for the free and reduced lunch program. This relationship is particularly acute at secondary levels, but additional factors appear to be at play at elementary grade levels
Viscosity dependence of the rates of diffusional processes
It is shown that the rates of diffusion-controlled processes may have a solvent vicosity independent part as well as a viscosity dependent part. Some relevant experiments involving intramolecular polypeptide movements are discussed, and implications for some experiments on diffusion in membranes are outlined
Protein folding, protein structure and the origin of life: Theoretical methods and solutions of dynamical problems
Theoretical methods and solutions of the dynamics of protein folding, protein aggregation, protein structure, and the origin of life are discussed. The elements of a dynamic model representing the initial stages of protein folding are presented. The calculation and experimental determination of the model parameters are discussed. The use of computer simulation for modeling protein folding is considered
Recommended from our members
Job Performance Comparisons - Mexican-American and Anglo Employees
A comparison of job performance of Mexican-American and non-Mexican-American employees in various city departments and in a large department store measured absentee rates, accident rates, efficiency ratings, promotional test scores, and sales records. The conclusions revealed that Mexican-Americans meet the same qualifications as non-Mexican-Americans in employment areas.Sociolog
Designing Crop Insurance to Manage Moral Hazard Costs
A new crop insurance model based on just random risk (natural states) is presented instead of traditional model based on random risk, guaranteed price, and guaranteed yield. The simulation approach shows how the incentive compatibility constraints resolve the moral hazard problem by the insured under the insurer-agency crop insurance contracting.Risk and Uncertainty,
TARGETING ENVIRONMENTAL PROTECTION IN AGRICULTURE: IPM AND BMPS AS ENVIRONMENTAL PERFORMANCE INDICATORS
Nonparametric technical efficiency estimates of potentially polluting input use in soybean and wheat indicate substantial heterogeneity across farms. This implies large costs would be associated with uniform standards or incentives to regulate these inputs. While technical efficiency is not observable, indicators of environmentally beneficial practices are found useful predictors.technical efficiency, DEA, environment performance, pollution, Environmental Economics and Policy,
An implementation and analysis of the Abstract Syntax Notation One and the basic encoding rules
The details of abstract syntax notation one standard (ASN.1) and the basic encoding rules standard (BER) that collectively solve the problem of data transfer across incompatible host environments are presented, and a compiler that was built to automate their use is described. Experiences with this compiler are also discussed which provide a quantitative analysis of the performance costs associated with the application of these standards. An evaluation is offered as to how well suited ASN.1 and BER are in solving the common data representation problem
- âŠ