81 research outputs found

    Development and application of an acceptance testing model

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    The process of acceptance testing large software systems for NASA has been analyzed, and an empirical planning model of the process constructed. This model gives managers accurate predictions of the staffing needed, the productivity of a test team, and the rate at which the system will pass. Applying the model to a new system shows a high level of agreement between the model and actual performance. The model also gives managers an objective measure of process improvement

    Integration of a satellite ground support system based on analysis of the satellite ground support domain

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    This analysis defines a complete set of ground support functions based on those practiced in real space flight operations during the on-orbit phase of a mission. These functions are mapped against ground support functions currently in use by NASA and DOD. Software components to provide these functions can be hosted on RISC-based work stations and integrated to provide a modular, integrated ground support system. Such modular systems can be configured to provide as much ground support functionality as desired. This approach to ground systems has been widely proposed and prototyped both by government institutions and commercial vendors. The combined set of ground support functions we describe can be used as a standard to evaluate candidate ground systems. This approach has also been used to develop a prototype of a modular, loosely-integrated ground support system, which is discussed briefly. A crucial benefit to a potential user is that all the components are flight-qualified, thus giving high confidence in their accuracy and reliability

    Cottrell Scholars Collaborative New Faculty Workshop: Professional Development for New Chemistry Faculty and Initial Assessment of Its Efficacy

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    The Cottrell Scholars Collaborative New Faculty Workshop (CSC NFW) is a professional development program that was initiated in 2012 to address absences in the preparation of chemistry faculty at research universities as funded researchers and educators (i.e., teacher–scholars). The primary focus of the workshop is an introduction to evidence-based teaching methods; other topics including mentoring, work–life balance, time management, and grant writing are also addressed. A longer-term aim of the workshop is to develop lifelong teacher–scholars by encouraging workshop participants to engage with teaching-focused faculty learning communities through the CSC NFW and at their institutions. The workshop also provides a platform to investigate the adoption of student-centered pedagogies among new faculty, and a study of that process was initiated concurrently. Thus, the aim of the workshop program is to address professional development needs as well as understand the efficacy of that effort

    Measuring perceived benefit and disease-related burden in young cancer survivors: validation of the Benefit and Burden Scale for Children (BBSC) in the Netherlands

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    Item does not contain fulltextPURPOSE: Perceiving favourable changes from one's illness may go hand in hand with experiencing harmful psychosocial effects. Each of these constructs should be considered when examining children's levels of psychological adjustment following stressful life events. A paediatric instrument that accounts for both positive and negative impact of stressful events has not been investigated in The Netherlands before. The aim of the study was to investigate psychometric properties of the Dutch version of the Benefit and Burden Scale for Children (BBSC), a 20-item questionnaire that intends to measure potential benefit and burden of illness in children. METHODS: Dutch paediatric survivors of childhood cancer aged 8-18 (N = 77) completed the BBSC and other psychological questionnaires: Pediatric Quality of Life Inventory (health-related quality of life), State-Trait Anxiety Inventory for Children (anxiety), Children's Revised Impact of Event Scale (posttraumatic stress) and Strengths and Difficulties Questionnaire (behavioural functioning). Reliability and validity were evaluated. RESULTS: Internal consistency (Cronbach's alpha, benefit 0.84, burden 0.72), test-retest reliability (benefit r = 0.74, burden r = 0.78) and homogeneity (mean inter-item correlation, benefit r = 0.34, burden r = 0.22) were satisfactory. Burden was associated with HRQoL (-), anxiety (+), posttraumatic stress symptoms (+) and behavioural problems. Benefit did not correlate with the psychological outcomes. CONCLUSIONS: The Dutch version of the BBSC shows promising psychometric properties. Perceived benefit and disease-related burden are distinct constructs; both should be considered when examining children's psychological adjustment to potentially traumatic experiences. The BBSC may be useful as monitoring and screening instrument

    Human monoclonal antibodies targeting carbonic anhydrase IX for the molecular imaging of hypoxic regions in solid tumours

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    BACKGROUND: Hypoxia, which is commonly observed in areas of primary tumours and of metastases, influences response to treatment. However, its characterisation has so far mainly been restricted to the ex vivo analysis of tumour sections using monoclonal antibodies specific to carbonic anhydrase IX (CA IX) or by pimonidazole staining, after the intravenous administration of this 2-nitroimidazole compound in experimental animal models.METHODS: In this study, we describe the generation of high-affinity human monoclonal antibodies (A3 and CC7) specific to human CA IX, using phage technology.RESULTS: These antibodies were able to stain CA IX ex vivo and to target the cognate antigen in vivo. In one of the two animal models of colorectal cancer studied (LS174T), CA IX imaging closely matched pimonidazole staining, with a preferential staining of tumour areas characterised by little vascularity and low perfusion. In contrast, in a second animal model (SW1222), distinct staining patterns were observed for pimonidazole and CA IX targeting. We observed a complementary pattern of tumour regions targeted in vivo by the clinical-stage vascular-targeting antibody L19 and the anti-CA IX antibody A3, indicating that a homogenous pattern of in vivo tumour targeting could be achieved by a combination of the two antibodies.CONCLUSION: The new human anti-CA IX antibodies are expected to be non-immunogenic in patients with cancer and may serve as broadly applicable reagents for the non-invasive imaging of hypoxia and for pharmacodelivery applications. British Journal of Cancer (2009) 101, 645-657. doi: 10.1038/sj.bjc.6605200 www.bjcancer.com Published online 21 July 2009 (C) 2009 Cancer Research U

    A chronoamperometric method to estimate changes in the membrane composition of ion-selective membranes

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    A new chronoamperometric method is used to estimate changes in the membrane composition of mobile-site, ionophore-based membranes. The characteristic features of the chronoamperometric curves (initial current, slope, break time) of valinomycin-based, potassium-selective membranes loaded with potassium tetrakis(4-chlorophenyl)borate are correlated with the mobile-site and free ionophore concentration in the membrane. Limiting cases for strong and negligible ion pair formation are distinguished. Replicate measurements indicate a relative standard deviation in the calculated values less than 10%. The practical applicability of the method was tested with membranes incorporated into conventional ion-selective electrode bodies or cast onto microfabricated planar sensor structures
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