Passing Muster: Evaluating Teacher Evaluation Systems

Describes how state or federal governments could reward exceptional teachers based on a uniform standard across various district-level teacher evaluation systems by determining the systems' reliability in predicting future performance. Includes Q & A

Evaluating Teachers: The Important Role of Value-Added

Outlines issues for evaluating teachers based on value added -- their contribution to student learning -- and the use of value added information, implications of classifying teachers, and reliability compared with other fields and evaluations

A comparison of the performance of new and used common rail diesel injectors

An investigation was conducted into the effects of wear on the performance of common-rail fuel injectors, in terms of flow and spray characteristics. The investigation conducted involved the testing of four used injectors, and the comparison of the performance of these injectors with that of an identical brand new injector. The used injectors had deteriorated in different ways, with solenoid wear, mechanical wear in the body of the injector, and mechanical wear in the upper section of the injector being identified. All of the manners of deterioration affected the flow characteristics. The solenoid wear and mechanical wear in the body did not affect the spray performance, but wear in the upper section of the body and a combination of wear in the body and solenoid did affect spray performance. A correlation was developed between the spray penetration of the new injector and the spray theories according to Dent and Hiroyasu

On Numerical Modeling of Equal Channel Angular Extrusion of Ultra High Molecular Weight Polyethylene

Ultra high molecular weight polyethylene (UHMWPE) is widely used in biomedical applications, e.g. as a bearing surface in total joint arthroplasty. Recently, equal channel angular extrusion (ECAE) was proposed as a processing method to achieve higher molecular entanglement and superior mechanical properties of this material. Numerical modeling can be utilized to evaluate the influence of such important manufacturing parameters as the extrusion rate, temperature, geometry of the die, back pressure and friction effects in the ECAE of polyethylenes. In this paper we focus on the development of efficient FE models of ECAE for UHMWPE. We study the applicability of the available constitutive models traditionally used in polymer mechanics for UHMWPE, evaluate the importance of the proper choice of the friction parameters between the billet and the die, and compare the accuracy of predictions between 2D (plane strain) and 3D models. Our studies demonstrate that the choice of the constitutive model is extremely important for the accuracy of numerical modeling predictions. It is also shown that the friction coefficient significantly influences the punch force and that 2D plane strain assumption can become inaccurate in the presence of friction between the billet and the extrusion channel

Technical Report: Distributed Parallel Computing Using Windows Desktop Systems

See also: http://sbml.org/Main_PageLike many large institutions, Indiana University has thousands of desktop computers devoted primarily to running office productivity applications on the Windows operating system, tasks which are necessary but that do not use the computers’ full capacity. This is a resource worth pursuing. However, the individual desktop systems do not offer enough processing power for a long enough period of time to complete large scientific computing applications. Some form of distributed, parallel programming is required, to make them worth the chase. They must be instantly available to their primary users, so they are available only intermittently. This has been a serious stumbling block: currently available communications libraries for distributed computing do not support such a dynamic communications world well. This paper introduces Simple Message Broker Library (SMBL), which provides the flexibility needed to take advantage of such ephemeral resources

QuickSNP: an automated web server for selection of tagSNPs

Although large-scale genetic association studies involving hundreds to thousands of SNPs have become feasible, the associated cost is substantial. Even with the increased efficiency introduced by the use of tagSNPs, researchers are often seeking ways to maximize resource utilization given a set of SNP-based gene-mapping goals. We have developed a web server named QuickSNP in order to provide cost-effective selection of SNPs, and to fill in some of the gaps in existing SNP selection tools. One useful feature of QuickSNP is the option to select only gene-centric SNPs from a chromosomal region in an automated fashion. Other useful features include automated selection of coding non-synonymous SNPs, SNP filtering based on inter-SNP distances and information regarding the availability of genotyping assays for SNPs and whether they are present on whole genome chips. The program produces user-friendly summary tables and results, and a link to a UCSC Genome Browser track illustrating the position of the selected tagSNPs in relation to genes and other genomic features. We hope the unique combination of features of this server will be useful for researchers aiming to select markers for their genotyping studies. The server is freely available and can be accessed at the URL http://bioinformoodics.jhmi.edu/quickSNP.pl

Developmentally Sensitive Implementation of Core Elements of Evidence-Based Treatments: Practical Strategies for Youth With Internalizing Disorders

MANY TREATMENT APPROACHES for psychological disorders among children and adolescents are downward extensions of adult treatment models. According to Barrett (2000), when treatments for childhood disorders are based on cognitive behavioral models of adult disorders, clinicians may make inaccurate assumptions, such as viewing children as “little adults,” thereby failing to adjust treatment terminology for children and ignoring contextual factors such as families and peers. Subscribing to adult models may also result in a lack of awareness of research findings in the field of developmental psychology (e.g., cognitive abilities, social skills, emotion regulation) and, consequently, implementation of treatment strategies in a similar manner across levels of development (e.g., assuming all children possess the same level of meta-cognitive skills). As Kingery and colleagues (2006) emphasize, simply utilizing a treatment that has been developed for youth is not sufficient. Particularly when implementing manual-based CBT for youth with internalizing disorders, clinicians must be knowledgeable, creative, and flexible, taking each child’s individual cognitive, social, and emotional skills into consideration to provide the most developmentally appropriate intervention

Computational complexity of the landscape I

We study the computational complexity of the physical problem of finding vacua of string theory which agree with data, such as the cosmological constant, and show that such problems are typically NP hard. In particular, we prove that in the Bousso-Polchinski model, the problem is NP complete. We discuss the issues this raises and the possibility that, even if we were to find compelling evidence that some vacuum of string theory describes our universe, we might never be able to find that vacuum explicitly. In a companion paper, we apply this point of view to the question of how early cosmology might select a vacuum.Comment: JHEP3 Latex, 53 pp, 2 .eps figure

A novel method for monitoring mineralisation in hydrogels at the engineered hard–soft tissue interface

The capacity to study the deposition of mineral within a hydrogel structure is of significant interest to a range of therapies that seek to replace the hard tissues and the hard–soft tissue interface. Here, a method is presented that utilises Confocal Raman microscopy as a tool for monitoring mineralisation within hydrogels. Synthetic hard–soft material interfaces were fabricated by apposing brushite (a sparingly soluble calcium phosphate) and biopolymer gel monoliths. The resulting structures were matured over a period of 28 days in phosphate buffered saline. Confocal Raman microscopy of the interfacial region showed the appearance of calcium phosphate salt deposits away from the original interface within the biopolymeric structures. Furthermore, the appearance of octacalcium phosphate and carbonated hydroxyapatite was observed in the region of the brushite cement opposing the biopolymer gel. This study describes not only a method for analysing these composite structures, but also suggests a method for recapitulating the graduated tissue structures that are often found in vivo

Perception of American English Consonants /v/ and /w/ by Hindi Speakers of English

This study examined perception of the American English (AE) /v/-/w/ consonant contrast by Hindi speakers of English as a second language (L2). A second aim was to determine whether residence in the US modulated perception of this difficult contrast for proficient bilingual Hindi-English listeners. Two groups of Hindi-English bilinguals (the first resided in the US for more than five years, the second lived in India) and a group of AE-speaking listeners participated in the study. Listeners’ identification and discrimination of nonsense words (e.g., “vagag” vs. “wagag”) were examined. Hindi listeners performed significantly less accurately than AE controls. Accuracy by Hindi listeners was near chance for identification and higher-than-chance for discrimination. Exposure to AE in the US did not improve performance. These results are consistent with previous studies of late L2 learners and extend findings to a population that was proficient in an L2 before arriving in the L2 environment