311 research outputs found

    A 3-D display head-set for personalized computing

    Get PDF
    Thesis (M.S.V.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1983.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCHIncludes bibliographical references (leaves 106-109).This thesis covers the design and implementation of a binocular display head-set akin to Dr . Ivan E. Sutherland's head-mounted display, but using several new technologies and new techniques in computer graphics: small portable video display, transmitter and receiver; write-once optical video disc recorder; a magnetic position sensor, and a depth cue based animation package. This implementation has permitted the creation of a highly interactive three dimensional trainer/simulator . Computer generated controlled images are optically mixed into the surrounding environment by imaging through two beamsplitter mirrors positioned in front of the viewer's eyes. The source of the images on the display head-set is two Sony Flat CRT's mounted on top of the head-set pointing downward. The beamsplitter mirrors are angled out from the bottom of a pair of eyeglasses. Normal vision is through the eyeglasses; the TV images are reflected in the mirrors . The viewer is able to manipulate the display image by "touching" and "moving" the image with his hand, or even to "look around" the display image. A position sensor located on either the viewers hand or the head-set itself provides the - input for the manipulation. Stereo for 3-D viewing is obtained by transmitting two video sources to the two receivers on two OHF channels located in a small beltpack. This thesis also describes a write-once optical video disc recorder that is used to store "pre-computed" view-point dependent images. The images of a scene were recorded in coherent segments to create a visual data base; included were full rotations and general movements of stereoscopic image pairs. Real-time manipulation of the pre-recorded images is done though fast-executing commands on the optical write-once recorder. The graphics package permits quick construction and scripting of objects. To increase the sensation of 3-D, special attention is paid to the inclusion and the highlighting of physiological and psychological depth cues.by Mark A. Callahan.M.S.V.S

    Progress in heavy ion target capsule and hohlraum design

    Full text link

    Connecting Science with Engineering: Using Inquiry and Design in a Teacher Professional Development Course

    Get PDF
    The engineering design process has evolved over time to be the central and effective framework that engineers use to conduct their work. Logically, K-12 STEM professional development efforts have then attempted to incorporate the design process into their work. There has been little in the STEM literature, though, of the explicit measurement of the growth in design process knowledge. Our study presents findings of significant improvements in knowledge of the design process that resulted over the course of a recent summer STEM institute and professional development program among K-5 teachers. As more emphasis is placed on integrating STEM into the curriculum 1 there is a need to enhance the capacity for K-12 teachers. Responding to this call the Colleges of Engineering and Education at Boise State University collaborated to offer an intensive three-day summer institute to address the preparation of elementary school teachers (grades K-5) to teach STEM curriculum. The focus of our institute was on the use of both inquiry and design as approaches for integrating STEM content. In particular we explicitly stressed the link between science and inquiry and engineering and design, how these processes differ, how they can complement each other and how they can be used instructionally to teach a wide range of STEM content. The instructional materials used in the workshop included Lego®-like bricks called PCS BrickLab® (supplied by PCS Edventures! an educational products company) and other common classroom items such as paper, tape, string, and cardboard.. Each participant received a classroom set of the materials at the close of the workshop. The BrickLab® kit contains over 5,000 bricks which is sufficient to simultaneously engage up to about 30 students in hands-on activities, which makes these instructional materials particularly suitable to facilitate classroom instruction using inquiry and design. We engaged the participants in a series of hands-on activities focused on the inquiry process of manipulating variables to gather data to explain phenomena or design processes that focus on creating and refining the best solution given constraints. To determine the effectiveness of our workshop we gathered pre and post data to assess our 58 participants\u27 comfort for teaching STEM, their STEM pedagogical discontentment, their implementation of inquiry curriculum, and their knowledge of the design process. Our initial results indicate significant increases in comfort teaching STEM (t = 12.761, p \u3c .01), decreases in STEM pedagogical discontentment (t = 7.281, p \u3c .01), and increases in design process knowledge (t = 6.072, p \u3c .01). Delayed post data collection for the implementation of inquiry took place in Fall 2010, which allowed time for the participating teachers to apply their learned knowledge and develop a post conference context for their instructional practice with students. All instruments used for data collection were extant and had established reliability and validity. Our results indicate that our three-day summer institute and follow-up support increased our participants\u27 knowledge of design along with comfort for teaching STEM. Also, the institute decreased the teachers’ pedagogical discontentment for teaching STEM

    The Grizzly, February 10, 1984

    Get PDF
    Guards Receive Training • Internships for Credit • Alcoholism: Prime Health Problem • Businessman to Share Experiences • Fish Find a Home • China in the 20th Century • Television Forum Presented • DJ Spotlight on...Ed Johns • Two Decades of the Beatles • Grapplers Keep Rolling • Lady Bears Quash Cabrini • Bears Impressive in Win Over Drew • UC Gymnasts Post Best Score of Seasonhttps://digitalcommons.ursinus.edu/grizzlynews/1112/thumbnail.jp

    Optimization of biotinyl-tyramide-based in situ hybridization for sensitive background-free applications on formalin-fixed, paraffin-embedded tissue specimens

    Get PDF
    BACKGROUND: Over the past five years in situ hybridization techniques employing tyramide amplification reagents have been developed and promise the potential detection of low/single-copy nucleic acid sequences. However the increased sensitivity that tyramide amplification brings about may also lead to problems of background staining that confound data interpretation. METHODS: In this study those factors enabling background-free biotinyl-tyramide based in situ hybridization assay of formalin-fixed paraffin-embedded tissues have been examined. SiHa, HeLa and CaSki cell lines known to contain HPV integrated into the cell genome, and archival cervical pre-invasive lesions and carcinomas have been successfully assessed using biotinylated HPV and centromeric probes. RESULTS: The single most important factor both for sensitivity and clean background was a tissue unmasking regimen that included treatment with 10 mM sodium citrate pH 6.0 at 95°C followed by digestion with pepsin/0.2 M HCl. Concentrations both of probe and primary streptavidin-peroxidase conjugate and pH of hybridization mix and stringency washes were also critical for sensitivity. Certain probes were more associated with background staining than others. This problem was not related to probe purity or size. In these instances composition of hybridization mix solution was especially critical to avoid background. 3-amino-9-ethylcarbazole was preferred over 3,3'-diaminobenzidene as a chromogen because background was cleaner and the 1–2 copies of HPV16 integrated in SiHa cells were readily demonstrable. HPV detection on metaphase spreads prepared from SiHa cells was only successful when a fluorescent detection method was combined with tyramide reagent. 'Punctate' and 'diffuse' signal patterns were identified amongst tissues consistent with the former representing integration and 'diffuse' representing episomal HPV. Only punctate signals were detected amongst the cell lines and were common amongst high-grade pre-invasive lesions and carcinomas. However it remains to be determined why single/low-copy episomal HPV in basal/parabasal cells of low-grade lesions is not also detectable using tyramide-based techniques and whether every punctate signal represents integration. CONCLUSIONS: A tyramide-based in situ hybridization methodology has been established that enables sensitive, background-free assay of clinical specimens. As punctate signals characterize HPV in high-grade cervical lesions the method may have potential for clinical applications

    Development and psychometric analysis of the PROMIS pain behavior item bank

    Get PDF
    The measurement of pain behavior is a key component of the assessment of persons with chronic pain; however few self-reported pain behavior instruments have been developed. We developed a pain behavior item bank as part of the Patient Reported Outcome Measurement Information System (PROMIS). For the Wave I testing, because of the large number of PROMIS items, a complex sampling approach was used where participants were randomly assigned to either respond to two full item banks or to multiple 7-item blocks of items. A web-based survey was designed and completed by 15,528 members of the general population and 967 individuals with different types of chronic pain. Item response theory (IRT) analysis models were used to evaluate item characteristics and to scale both items and individuals on the pain behavior domain. The pain behavior item bank demonstrated good fit to a unidimensional model (Comparative Fit Index = 0.94). Several iterations of IRT analyses resulted in a final 39 item pain behavior bank, and different IRT models were fit to the total sample and to those participants who experienced some pain. The results indicated that these items demonstrated good coverage of the pain behavior construct. Pain behavior scores were strongly related to pain intensity and moderately related to self-reported general health status. Mean pain behavior scores varied significantly by groups based on pain severity and general health status. The PROMIS pain behavior item bank can be used to develop static short-form and dynamic measures of pain behavior for clinical studies

    Glucose testing and insufficient follow-up of abnormal results: a cohort study

    Get PDF
    BACKGROUND: More than 6 million Americans have undiagnosed diabetes. Several national organizations endorse screening for diabetes by physicians, but actual practice is poorly understood. Our objectives were to measure the rate, the predictors and the results of glucose testing in primary care, including rates of follow-up for abnormal values. METHODS: We conducted a retrospective cohort study of 301 randomly selected patients with no known diabetes who received care at a large academic general internal medicine practice in New York City. Using medical records, we collected patients' baseline characteristics in 1999 and followed patients through the end of 2002 for all glucose tests ordered. We used multivariate logistic regression to measure associations between diabetes risk factors and the odds of glucose testing. RESULTS: Three-fourths of patients (78%) had at least 1 glucose test ordered. Patient age (≥45 vs. <45 years), non-white ethnicity, family history of diabetes and having more primary care visits were each independently associated with having at least 1 glucose test ordered (p < 0.05), whereas hypertension and hyperlipidemia were not. Fewer than half of abnormal glucose values were followed up by the patients' physicians. CONCLUSION: Although screening for diabetes appears to be common and informed by diabetes risk factors, abnormal values are frequently not followed up. Interventions are needed to trigger identification and further evaluation of abnormal glucose tests

    Constitutive Overexpression of the OsNAS Gene Family Reveals Single-Gene Strategies for Effective Iron- and Zinc-Biofortification of Rice Endosperm

    Get PDF
    BACKGROUND: Rice is the primary source of food for billions of people in developing countries, yet the commonly consumed polished grain contains insufficient levels of the key micronutrients iron (Fe), zinc (Zn) and Vitamin A to meet daily dietary requirements. Experts estimate that a rice-based diet should contain 14.5 µg g−1 Fe in endosperm, the main constituent of polished grain, but breeding programs have failed to achieve even half of that value. Transgenic efforts to increase the Fe concentration of rice endosperm include expression of ferritin genes, nicotianamine synthase genes (NAS) or ferritin in conjunction with NAS genes, with results ranging from two-fold increases via single-gene approaches to six-fold increases via multi-gene approaches, yet no approach has reported 14.5 µg g−1 Fe in endosperm. METHODOLOGY/PRINCIPAL FINDINGS: Three populations of rice were generated to constitutively overexpress OsNAS1, OsNAS2 or OsNAS3, respectively. Nicotianamine, Fe and Zn concentrations were significantly increased in unpolished grain of all three of the overexpression populations, relative to controls, with the highest concentrations in the OsNAS2 and OsNAS3 overexpression populations. Selected lines from each population had at least 10 µg g−1 Fe in polished grain and two OsNAS2 overexpression lines had 14 and 19 µg g−1 Fe in polished grain, representing up to four-fold increases in Fe concentration. Two-fold increases of Zn concentration were also observed in the OsNAS2 population. Synchrotron X-ray fluorescence spectroscopy demonstrated that OsNAS2 overexpression leads to significant enrichment of Fe and Zn in phosphorus-free regions of rice endosperm. CONCLUSIONS: The OsNAS genes, particularly OsNAS2, show enormous potential for Fe and Zn biofortification of rice endosperm. The results demonstrate that rice cultivars overexpressing single rice OsNAS genes could provide a sustainable and genetically simple solution to Fe and Zn deficiency disorders affecting billions of people throughout the world.Alexander A. T. Johnson, Bianca Kyriacou, Damien L. Callahan, Lorraine Carruthers, James Stangoulis, Enzo Lombi and Mark Teste

    Communications Biophysics

    Get PDF
    Contains research objectives, summary of research and reports on two research project.National Institutes of Health (Grant 5 PO1 GM14940-03)National Institutes of Health (Grant 5 TO1 GM01555-03)National Aeronautics and Space Administration (Grant NGL 22-009-304

    A study of the diagnostic accuracy of the PHQ-9 in primary care elderly

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The diagnostic accuracy of the Patient Health Questionnaire-9 (PHQ-9) for assessment of depression in elderly persons in primary care settings in the United States has not been previously addressed. Thus, the purpose of this study was to evaluate the test performance of the PHQ-9 for detecting major and minor depression in elderly patients in primary care.</p> <p>Methods</p> <p>A prospective study of diagnostic accuracy was conducted in two primary care, university-based clinics in the Pacific Northwest of the United States. Seventy-one patients aged 65 years or older participated; all completed the PHQ-9 and the 15-item Geriatric Depression Scale (GDS) and underwent the Structured Clinical Interview for Depression (SCID). Sensitivity, specificity, area under the receiver operating characteristic (ROC) curve, and likelihood ratios (LRs) were calculated for the PHQ-9, the PHQ-2, and the 15-item GDS for major depression alone and the combination of major plus minor depression.</p> <p>Results</p> <p>Two thirds of participants were female, with a mean age of 78 and two chronic health conditions. Twelve percent met SCID criteria for major depression and 13% minor depression. The PHQ-9 had an area under the curve (AUC) of 0.87 (95% confidence interval [CI], 0.74-1.00) for major depression, while the PHQ-2 and the 15-item GDS each had an AUC of 0.81 (95% CI for PHQ-2, 0.64-0.98, and for 15-item GDS, 0.70-0.91; <it>P </it>= 0.551). For major and minor depression combined, the AUC for the PHQ-9 was 0.85 (95% CI, 0.73-0.96), for the PHQ-2, 0.80 (95% CI, 0.68-0.93), and for the 15-item GDS, 0.71 (95% CI, 0.55-0.87; <it>P </it>= 0.187).</p> <p>Conclusions</p> <p>Based on AUC values, the PHQ-9 performs comparably to the PHQ-2 and the 15-item GDS in identifying depression among primary care elderly.</p
    • …
    corecore