232 research outputs found

    Techniques for optimal crop selection in a controlled ecological life support system

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    A Controlled Ecological Life Support System (CELSS) utilizes a plant's natural ability to regenerate air and water while being grown as a food source in a closed life support system. Current plant research is directed toward obtaining quantitative empirical data on the regenerative ability of each species of plant and the system volume and power requirements. Two techniques were adapted to optimize crop species selection while at the same time minimizing the system volume and power requirements. Each allows the level of life support supplied by the plants to be selected, as well as other system parameters. The first technique uses decision analysis in the form of a spreadsheet. The second method, which is used as a comparison with and validation of the first, utilizes standard design optimization techniques. Simple models of plant processes are used in the development of these methods

    Digital control of the Kuiper Airborne Observatory telescope

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    The feasibility of using a digital controller to stabilize a telescope mounted in an airplane is investigated. The telescope is a 30 in. infrared telescope mounted aboard a NASA C-141 aircraft known as the Kuiper Airborne Observatory. Current efforts to refurbish the 14-year-old compensation system have led to considering a digital controller. A typical digital controller is modeled and added into the telescope system model. This model is simulated on a computer to generate the Bode plots and time responses which determine system stability and performance parameters. Important aspects of digital control system hardware are discussed. A summary of the findings shows that a digital control system would result in satisfactory telescope performance

    Prevalence of mental health conditions and relationship with general health in a whole-country population of people with intellectual disabilities compared with the general population

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    Background: There are no previous whole-country studies on mental health and relationships with general health in intellectual disability populations; study results vary. Aims: To determine the prevalence of mental health conditions and relationships with general health in a total population with and without intellectual disabilities. Method: Ninety-four per cent completed Scotland’s Census 2011. Data on intellectual disabilities, mental health and general health were extracted, and the association between them was investigated. Results: A total of 26 349/5 295 403 (0.5%) had intellectual disabilities. In total, 12.8% children, 23.4% adults and 27.2% older adults had mental health conditions compared with 0.3, 5.3 and 4.5% of the general population. Intellectual disabilities predicted mental health conditions; odds ratio (OR)=7.1 (95% CI 6.8–7.3). General health was substantially poorer and associated with mental health conditions; fair health OR=1.8 (95% CI 1.7–1.9), bad/very bad health OR=4.2 (95% CI 3.9–4.6). Conclusions: These large-scale, whole-country study findings are important, given the previously stated lack of confidence in comparative prevalence results, and the need to plan services accordingly

    Techniques for optimal crop selection in a controlled ecological life support system

    Get PDF
    A Controlled Ecological Life Support System (CELSS) utilizes a plant's natural ability to regenerate air and water while being grown as a food source in a closed life support system. Current plant research is directed toward obtaining quantitative empirical data on the regenerative ability of each species of plant and the system volume and power requirements. Two techniques were adapted to optimize crop species selection while at the same time minimizing the system volume and power requirements. Each allows the level of life support supplied by the plants to be selected, as well as other system parameters. The first technique uses decision analysis in the form of a spreadsheet. The second method, which is used as a comparison with and validation of the first, utilizes standard design optimization techniques. Simple models of plant processes are used in the development of these methods

    Valve interstitial cells induce donor-specific T-cell anergy

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    AbstractObjectives: Valve allografts produce an immune response, which can influence their performance. The exact role of the interaction between recipient T cells and the different cellular components of the donor valve in stimulating an immune response is not known. Therefore the T-cell response to valve endothelial and interstitial cells was investigated in vitro. Methods: Valve endothelial and interstitial cells were characterized for cell-surface molecules before and after interferon γ treatment by means of a panel of specific monoclonal antibodies and flow cytometry. The proliferative response of highly purified T lymphocytes was used to assess the immunogenicity of cultured valve endothelial and interstitial cells. This was further investigated by using a 2-step tolerance-induction protocol. Results: Valve endothelial and interstitial cells express similar levels of human leukocyte antigens and adhesion and costimulatory molecules, which are either induced or upregulated after interferon γ treatment. T-cell responses to endothelial cells were detected after interferon γ treatment, but responses to interferon γ–treated interstitial cells were not detected. This lack of response resulted in the induction of T-cell anergy, which was reversed by the presence of the costimulatory molecule B7-1. Conclusions: Although valve endothelial and interstitial cells express a similar range of cell-surface molecules, it is only the endothelial cells that are immunogenic. In addition, we have shown that these 2 cell types interact in a donorspecific manner to orchestrate the immune response and therefore may have clinical relevance in the allogeneic response of the heart valve recipients.J Thorac Cardiovasc Surg 2001;122:129-3

    Fatal high-grade skull osteosarcoma 30 years following radiotherapy for Cushing's disease

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    Cushing’s disease is a rare disorder characterised by excessive cortisol production as a consequence of a corticotroph pituitary tumour. While the primary treatment is surgical resection, post-operative radiation therapy may be used in cases of ongoing inadequate hormonal control or residual or progressive structural disease. Despite improved outcomes, radiotherapy for pituitary tumours is associated with hypopituitarism, visual deficits and, rarely, secondary malignancies. We describe an unusual case of a 67-year-old female with presumed Cushing’s disease diagnosed at the age of 37, treated with transsphenoidal resection of a pituitary tumour with post-operative external beam radiotherapy (EBRT), ketoconazole for steroidogenesis inhibition, and finally bilateral adrenalectomy for refractory disease. She presented 30 years after her treatment with a witnessed generalised tonic-clonic seizure. Radiological investigations confirmed an extracranial mass infiltrating through the temporal bone and into brain parenchyma. Due to recurrent generalised seizures, the patient was intubated and commenced on dexamethasone and anti-epileptic therapy. Resection of the tumour revealed a high-grade osteoblastic osteosarcoma. Unfortunately, the patient deteriorated in intensive care and suffered a fatal cardiac arrest following a likely aspiration event. We describe the risk factors, prevalence and treatment of radiation-induced osteosarcoma, an exceedingly rare and late complication of pituitary irradiation. To our knowledge, this is the longest reported latency period between pituitary irradiation and the development of an osteosarcoma of the skull

    Prevalence of sensory impairments, physical and intellectual disabilities, and mental health in children and young people with self/proxy-reported autism: observational study of a whole country population

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    This study investigated the comorbid conditions in a whole country population of children/young people aged 0–24 years with and without autism. Data were drawn from Scotland’s Census 2011. We calculated the percentage with autism, their extent of comorbid conditions, odds ratio (with 95% confidence intervals) of autism predicting comorbidities, adjusted for age and gender, and odds ratio for age and gender predicting comorbidities within the cohort with autism. A total of 25,063/1,548,819 (1.6%) had autism: 19,880 (79.3%) males and 5183 (20.7%) females. Autism had an odds ratio of 5.4 (5.1–5.6) for predicting deafness/partial hearing loss, odds ratio of 8.9 (8.1–9.7) for blindness/partial sight loss, odds ratio of 49.7 (38.1–64.9) for intellectual disabilities, odds ratio of 15.7 (13.4–18.5) for mental health conditions, odds ratio of 15.8 (14.1–17.8) for physical disability and odds ratio of 3.9 (3.8–4.0) for other conditions. Females with autism were more likely to have each additional condition than males, including intellectual disabilities, suggesting they may have more severe autism than males and adding evidence that autism may be currently underdiagnosed in more intellectually able females. These conditions are disabling and have a significant impact on long-term quality of life; their coexistence with autism adds extra complexity. It is important to raise clinicians’ awareness of this extent of comorbidity, and to have accurate prevalence data to plan prevention and intervention measures, and to follow health inequality trends

    The relative influence of intellectual disabilities and autism on mental and general health in Scotland: a cross-sectional study of a whole country of 5.3 million children and adults

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    Objectives: To determine the relative extent that autism and intellectual disabilities are independently associated with poor mental and general health, in children and adults. Design: Cross-sectional study. For Scotland’s population, logistic regressions investigated odds of intellectual disabilities and autism predicting mental health conditions, and poor general health, adjusted for age and gender. Participants: 1 548 819 children/youth aged 0-24 years, and 3 746 584 adults aged more than 25 years, of whom 9396/1 548 819 children/youth had intellectual disabilities (0.6%), 25 063/1 548 819 children/youth had autism (1.6%); and 16 953/3 746 584 adults had intellectual disabilities (0.5%), 6649/3 746 584 adults had autism (0.2%). These figures are based on self-report. Main outcome measures: Self-reported general health status and mental health. Results: In children/youth, intellectual disabilities (OR 7.04, 95% CI 6.30 to 7.87) and autism (OR 25.08, 95% CI 23.08 to 27.32) both independently predicted mental health conditions. In adults, intellectual disabilities (OR 3.50, 95% CI 3.20 to 3.84) and autism (OR 5.30, 95% CI 4.80 to 5.85) both independently predicted mental health conditions. In children/youth, intellectual disabilities (OR 18.34, 95% CI 17.17 to 19.58) and autism (OR 8.40, 95% CI 8.02 to 8.80) both independently predicted poor general health. In adults, intellectual disabilities (OR 7.54, 95% CI 7.02 to 8.10) and autism (OR 4.46, 95% CI 4.06 to 4.89) both independently predicted poor general health. Conclusions: Both intellectual disabilities and autism independently predict poor health, intellectual disabilities more so for general health and autism more so for mental health. Intellectual disabilities and autism are not uncommon, and due to their associated poor health, sufficient services/supports are needed. This is not just due to coexistence of these conditions or just to having intellectual disabilities, as the population with autism is independently associated with substantial health inequalities compared with the general population, across the entire life course
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