Long term cryogenic storage facility systems study

The Long Term Cryogenic Storage Facility Systems Study (LTCSFSS) is a Phase A study of a large capacity propellant depot for the space based, cryogenic orbital transfer vehicle. The study is being performed for Marshall Space Flight Center by General Dynamics Space Systems Division and has five principal objectives: (1) Definition of preliminary concept designs for four storage facility concepts; (2) Selection of preferred concepts through the application of trade studies to candidate propellant management system components; (3) Preparation of a conceptual design for an orbital storage facility; (4) Development of supporting research and technology requirements; and (5) Development of a test program to demonstrate facility performance. The initial study has been completed, and continuation activities are just getting under way to provide greater detail in key areas and accommodate changes in study guidelines and assumptions

Anomie, Aspirations, and Delinquency: Implications for Education

The problem of this study is how can youth who have accepted deviant behavior as a pattern be identified. This study investigates relationships among anomie, aspirations, delinquency, and educational achievement, and it theorizes that students who are not anomic, hold high aspirations, and achieve normally in school will not exhibit deviant behavior as a pattern. The antithesis of the theoretical statement is also proposed

The Psychometric Validation of the International Baccalaureate Self-Study Questionnaire

The International Baccalaureate Self-Study Questionnaire: Diploma Programme is a self-study instrument that must be completed by IB Diploma Programme schools every five years as part of the IB program evaluation cycle. The purpose of this study was to psychometrically validate the self-study instrument. Content validity was examined through a modified Delphi technique using a panel of five experts. Construct validity was examined using a stratified random sample of 223 completed self-study questionnaires through a confirmatory factor analysis and internal consistency reliability check of the seven Likert scales contained in the instrument. Results validate portions of the instrument, but also indicate various validity and reliability issues that need to be addressed to strengthen the instrument. Recommendations for further research include a comparative analysis of IB schools completing the self-study questionnaire for the first time to IB schools completing the self-study questionnaire for the second or third time

Computing the shortest elementary flux modes in genome-scale metabolic networks

This article is available open access through the publisher’s website through the link below. Copyright @ The Author 2009.Motivation: Elementary flux modes (EFMs) represent a key concept to analyze metabolic networks from a pathway-oriented perspective. In spite of considerable work in this field, the computation of the full set of elementary flux modes in large-scale metabolic networks still constitutes a challenging issue due to its underlying combinatorial complexity. Results: In this article, we illustrate that the full set of EFMs can be enumerated in increasing order of number of reactions via integer linear programming. In this light, we present a novel procedure to efficiently determine the K-shortest EFMs in large-scale metabolic networks. Our method was applied to find the K-shortest EFMs that produce lysine in the genome-scale metabolic networks of Escherichia coli and Corynebacterium glutamicum. A detailed analysis of the biological significance of the K-shortest EFMs was conducted, finding that glucose catabolism, ammonium assimilation, lysine anabolism and cofactor balancing were correctly predicted. The work presented here represents an important step forward in the analysis and computation of EFMs for large-scale metabolic networks, where traditional methods fail for networks of even moderate size. Contact: [email protected] Supplementary information: Supplementary data are available at Bioinformatics online (http://bioinformatics.oxfordjournals.org/cgi/content/full/btp564/DC1).Fundação Calouste Gulbenkian, Fundação para a Ciência e a Tecnologia (FCT) and Siemens SA Portugal

Nocturnal nitrogen oxides at a rural mountain-site in south-western Germany

A new, two-channel instrument for simultaneous NO3 and N2O5 monitoring was used to make the first comprehensive set of nocturnal NOx measurements (NO, NO2, NO3 and N2O5) at the Taunus Observatory, a rural mountain site (Kleiner Feldberg) in South-western Germany. In May 2008, NO3 and N2O5 mixing ratios were well above the instrumental detection limit (a few ppt) on all nights of the campaign and were characterised by large variability. The concentrations of NO3, N2O5 and NO2 were consistent with the equilibrium constant, K2, defining the rates of formation and thermal dissociation of N2O5. A steady-state lifetime analysis is consistent with the loss of nocturnal NOx being dominated by the reaction of NO3 with volatile organic compounds in this forested region, with N2O5 uptake to aerosols of secondary importance. Analysis of a limited dataset obtained at high relative humidity indicated that the loss of N2O5 by reaction with water vapour is less efficient (>factor 3) than derived using laboratory kinetic data. The fraction of NOx present as NO3 and N2O5 reached ~20% on some nights, with night-time losses of NOx competing with daytime losses

Vocational Rehabilitation Outcomes for People with Mental Retardation, Cerebral Palsy, and Epilepsy: An Analysis of Trends from 1985 to 1998

This monograph presents the results of secondary analysis of the RSA-911 database from the Rehabilitation Services Administration. All successful VR closures for individuals with mental retardation, cerebral palsy, and epilepsy for six data points between 1985 and 1998 were investigated. Trends in competitive labor market and extended employment (sheltered workshops) closures were examined. The use of supported employment in the VR system and its outcomes were also discussed. Findings include increased incidence of competitive labor market closures and supported employment services, with a decrease in extended employment closures. Comparisons of successful VR closure outcomes to trends in the general labor market were also made. A significant inverse correlation between VR competitive labor market closure rates and national unemployment rates suggests that VR closures rise and decline with the performance of the general economy. The data also indicated a decrease in real (inflation adjusted) earnings at closure of 43% over the study time period. While there was also a decrease in real earnings for the general population, the decrease was more severe for VR closures