Apollo communications system support. Improvements in contact printing and metal masking techniques Final report, 1 Aug. 1967 - 29 Mar. 1968

Production methods for contact prints in emulsions or chromium coated glass plat

Conductor development for a wide bore 10 T Nb3Sn model dipole magnet

An 87.8 mm bore single aperture 10 T Nb3Sn model dipole magnet is under development as a next step in the realization of high-field Nb3Sn dipole magnets. The magnet is a 2 layer cos(&thetas;)-dipole model as an alternative for the proposed NbTi D1 beam separator magnets for the LHC. After completion of the general magnetic and mechanical design, all attention is focused on the manufacturing and cabling of a novel powder-in-tube Nb3Sn conductor. This Nb3Sn conductor is characterized by a high non-Cu Jc of 2680 A/mm2 at 10 T with an effective filament size of about 20 ¿m. Cabling should result in a Rutherford type of cable exhibiting a moderate Jc degradation due to the cabling process itself, a low transverse stress sensitivity and a controllable minimum value of Rc. The conductor development program is presented and the results are evaluated. Progress on the actual realization of the coils is briefly describe

Undergraduate Science Students and Electronic Scholarly Journals

Phase I of a 2‐phase project funded by the NSF‐National Science Digital Library Project used focus groups to determine how undergraduate science students perceive journal literature and how they use digital library resources. Their perceptions and use are contrasted with faculty and graduate teaching assistants in engineering, chemistry, and physics. Undergraduates have difficulties understanding journal articles. Although they consider themselves experts on the web, they rarely use online indexes or e‐journals unless required to for class. E‐Journals should be incrementally introduced to students starting at the time they declare a major. E‐Modules developed by the library and faculty could introduce the structure and content of articles, including links to glossaries and encyclopedias, tutorials about the publishing process, and study of the structure of articles

Development and psychometric testing of a multi-dimensional instrument of perceived discrimination among African Americans in the Jackson Heart Study

Objective Assessing the discrimination-health disparities hypothesis requires psychometrically sound, multidimensional measures of discrimination. Among the available discrimination measures, few are multidimensional and none have adequate psychometric testing in a large, African American sample. We report the development and psychometric testing of the multidimensional Jackson Heart Study Discrimination (JHSDIS) Instrument. Methods A multidimensional measure assessing the occurrence, frequency, attribution, and coping responses to perceived everyday and lifetime discrimination; lifetime burden of discrimination; and effect of skin color was developed and tested in the 5302-member cohort of the Jackson Heart Study. Internal consistency was calculated by using Cronbach α. coefficient. Confirmatory factor analysis established the dimensions, and intercorrelation coefficients assessed the discriminant validity of the instrument. Setting Tri-county area of the Jackson, MS metropolitan statistical area. Results The JHSDIS was psychometrically sound (overall α=.78, .84 and .77, respectively, for the everyday and lifetime subscales). Confirmatory factor analysis yielded 11 factors, which confirmed the a priori dimensions represented. Conclusions The JHSDIS combined three scales into a single multidimensional instrument with good psychometric properties in a large sample of African Americans. This analysis lays the foundation for using this instrument in research that will examine the association between perceived discrimination and CVD among African Americans. Keywords: Discrimination, Racism, Jackson Heart Study, African American, Cardiovascular Diseas

Duality symmetry of N=4 Yang-Mills theory on T^3

We study the spectrum of BPS states in N=4 supersymmetric U(N) Yang-Mills theory. This theory has been proposed to describe M-theory on T^3 in the discrete light-cone formalism. We find that the degeneracy of irreducible BPS bound states in this model exhibits a (partially hidden) SL(5,Z) duality symmetry. Besides the electro-magnetic symmetry, this duality group also contains Nahm-like transformations that interchange the rank N of the gauge group with some of the magnetic or electric fluxes. In the M-theory interpretation, this mapping amounts to a reflection that interchanges the longitudinal direction with one of the transverse directions.Comment: 16 pages, Latex, no figures. Some eqns in section 4 on Nahm duality correcte

Development and psychometric testing of a multi-dimensional instrument of perceived discrimination among African Americans in the Jackson Heart Study

Objective Assessing the discrimination-health disparities hypothesis requires psychometrically sound, multidimensional measures of discrimination. Among the available discrimination measures, few are multidimensional and none have adequate psychometric testing in a large, African American sample. We report the development and psychometric testing of the multidimensional Jackson Heart Study Discrimination (JHSDIS) Instrument. Methods A multidimensional measure assessing the occurrence, frequency, attribution, and coping responses to perceived everyday and lifetime discrimination; lifetime burden of discrimination; and effect of skin color was developed and tested in the 5302-member cohort of the Jackson Heart Study. Internal consistency was calculated by using Cronbach α. coefficient. Confirmatory factor analysis established the dimensions, and intercorrelation coefficients assessed the discriminant validity of the instrument. Setting Tri-county area of the Jackson, MS metropolitan statistical area. Results The JHSDIS was psychometrically sound (overall α=.78, .84 and .77, respectively, for the everyday and lifetime subscales). Confirmatory factor analysis yielded 11 factors, which confirmed the a priori dimensions represented. Conclusions The JHSDIS combined three scales into a single multidimensional instrument with good psychometric properties in a large sample of African Americans. This analysis lays the foundation for using this instrument in research that will examine the association between perceived discrimination and CVD among African Americans. Keywords: Discrimination, Racism, Jackson Heart Study, African American, Cardiovascular Diseas

Association of Cognitive Performance with Time at Altitude, Sleep Quality, and Acute Mountain Sickness Symptoms

Objective It is well documented that cognitive performance may be altered with ascent to altitude, but the association of various cognitive performance tests with symptoms of acute mountain sickness (AMS) is not well understood. Our objective was to assess and compare cognitive performance during a high-altitude expedition using several tests and to report the association of each test with AMS, headache, and quality of sleep. Methods During an expedition to Mount Everest, 3 cognitive tests (Stroop, Trail Making, and the real-time cognitive assessment tool, an in-house developed motor accuracy test) were used along with a questionnaire to assess health and AMS. Eight team members were assessed pre-expedition, postexpedition, and at several time points during the expedition. Results There were no significant differences (P >.05) found among scores taken at 3 time points at base camp and the postexpedition scores for all 3 tests. Changes in the Stroop test scores were significantly associated with the odds of AMS (P <.05). The logistic regression results show that the percent change from baseline for Stroop score (β = −5.637; P = .032) and Stroop attempts (β = −5.269; P = .049) are significantly associated with the odds of meeting the criteria for AMS. Conclusions No significant changes were found in overall cognitive performance at altitude, but a significant relationship was found between symptoms of AMS and performance in certain cognitive tests. This research shows the need for more investigation of objective physiologic assessments to associate with self-perceived metrics of AMS to gauge effect on cognitive performance

FALLING AS A STRATEGY TO DECREASE KNEE LOADING DURING LANDINGS

Anterior cruciate ligament injuries often occur when individuals land with a single leg. Falling has been suggested as a potential strategy to decrease knee loading during landings. The purpose was to compare knee flexion angles, peak impact forces, and peak knee extension moments among natural landings, soft landings, and falling in forward and vertical landing tasks under single or double leg conditions. Sixteen male and sixteen female participants completed each landing condition, while three-dimensional kinematics and ground reaction forces (GRF) were collected. In the natural landing condition, participants landed as they would in a sport setting. In the soft-landing condition, participants landed as softly as possible with increased knee and hip flexion. In the falling condition, participants initially landed softly and then fell forward or backward onto a mat in the forward and vertical landing tasks, respectively. Knee flexion angles at initial contact and peak knee flexion angles were generally the greatest for the falling, the second greatest for the soft landing, and the least for the natural landing. Peak vertical and posterior GRF and knee extension moments during early landing were generally the least for the falling, the second least for the soft landing, and the greatest for the natural landing. When the sports environment allows, falling appears to be an innovative strategy to decrease knee loading when individuals must land with a single leg and sub-optimal body postures

Screening for prediabetes and type 2 diabetes in dental offices

ObjectivesMost Americans see dentists at least once a year. Chair‐side screening and referral may improve diagnosis of prediabetes and diabetes. In this study, we developed a multivariate model to screen for dysglycemia (prediabetes and diabetes defined as HbA1c ≥5.7 percent) using information readily available to dentists and assessed the prevalence of dysglycemia in general dental practices.MethodsWe recruited 1,033 adults ≥30 years of age without histories of diabetes from 13 general dental practices. A sample of 181 participants selected on the basis of random capillary glucose levels and periodontal status underwent definitive diagnostic testing with hemoglobin A1c. Logistic models were fit to identify risk factors for dysglycemia, and sample weights were applied to estimate the prevalence of dysglycemia in the population ≥30 years of age.ResultsIndividuals at high risk for dysglycemia could be identified using a questionnaire that assessed sex, history of hypertension, history of dyslipidemia, history of lost teeth, and either self‐reported body mass index ≥35 kg/m2 (severe obesity) or random capillary glucose ≥110 mg/dl. We estimate that 30 percent of patients ≥30 years of age seen in these general dental practices had dysglycemia.ConclusionsThere is a substantial burden of dysglycemia in patients seen in general dental practices. Simple chair‐side screening for dysglycemia that includes or does not include fingerstick random capillary glucose testing can be used to rapidly identify high‐risk patients.Practical implicationsFurther studies are needed to demonstrate the acceptability, feasibility, effectiveness, and cost‐effectiveness of chair‐side screening.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/113762/1/jphd12082.pd