2,416 research outputs found

    A study of mapping exogenous knowledge representations into CONFIG

    Get PDF
    Qualitative reasoning is reasoning with a small set of qualitative values that is an abstraction of a larger and perhaps infinite set of quantitative values. The use of qualitative and quantitative reasoning together holds great promise for performance improvement in applications that suffer from large and/or imprecise knowledge domains. Included among these applications are the modeling, simulation, analysis, and fault diagnosis of physical systems. Several research groups continue to discover and experiment with new qualitative representations and reasoning techniques. However, due to the diversity of these techniques, it is difficult for the programs produced to exchange system models easily. The availability of mappings to transform knowledge from the form used by one of these programs to that used by another would open the doors for comparative analysis of these programs in areas such as completeness, correctness, and performance. A group at the Johnson Space Center (JSC) is working to develop CONFIG, a prototype qualitative modeling, simulation, and analysis tool for fault diagnosis applications in the U.S. space program. The availability of knowledge mappings from the programs produced by other research groups to CONFIG may provide savings in CONFIG's development costs and time, and may improve CONFIG's performance. The study of such mappings is the purpose of the research described in this paper. Two other research groups that have worked with the JSC group in the past are the Northwest University Group and the University of Texas at Austin Group. The former has produced a qualitative reasoning tool named SIMGEN, and the latter has produced one named QSIM. Another program produced by the Austin group is CC, a preprocessor that permits users to develop input for eventual use by QSIM, but in a more natural format. CONFIG and CC are both based on a component-connection ontology, so a mapping from CC's knowledge representation to CONFIG's knowledge representation was chosen as the focus of this study. A mapping from CC to CONFIG was developed. Due to differences between the two programs, however, the mapping transforms some of the CC knowledge to CONFIG as documentation rather than as knowledge in a form useful to computation. The study suggests that it may be worthwhile to pursue the mappings further. By implementing the mapping as a program, actual comparisons of computational efficiency and quality of results can be made between the QSIM and CONFIG programs. A secondary study may reveal that the results of the two programs augment one another, contradict one another, or differ only slightly. If the latter, the qualitative reasoning techniques may be compared in other areas, such as computational efficiency

    The distribution of maximum temperatures of coronal active region loops

    Get PDF
    The emission measure distribution across the range 4.5 log T 6.5 was derived for several coronal active regions by combining EUV line fluxes with broadband X-ray fluxes. The distributions of the maximum temperature was then derived using a numerical model. It is shown that the emission measure distribution can be represented over the full range 5.6 log Tm 6.5 by the superposition of simple loop models, if the models incorporate a substantial rise in their individual emission measure distributions near the maximum temperature. The unresolved loops may have substantial area ratios, since it is this ratio that fixes the extent of the rise in the emission measure distribution. Since the bulk of the emission measure is then contributed from the loop tops, the distribution of maximum temperatures has approximately the same shape as does the integrated emission measure distributions. The EUV and X-ray data used were obtained by from two separate experiments on ATM/Skylab

    The Role of Resilience in Rebuilding Lives of Injured Veterans

    Get PDF
    The aim of this commentary is to discuss potential clinical implications of introducing resilience building interventions into care for veterans who are living with a war wound. Some war veterans are expected to live with a wound upon discharge from an active military role and also to fit into civilian life. These lifestyle adjustments can tax the person’s coping abilities and in that context may hinder successful adaptation. The experience of living with a wound or wounds, either acute or chronic, is connected to losses, including loss of mobility, loss of financial capacity (unable to work during some of the wound healing period) and losses attached to changed social roles. Psychological stress is also a common experience for veterans returning to civilian life. Psychological stress is associated with impaired healing or dysregulation of a biomarker associated with wound healing. Modern health practice is centred on symptom reduction and working with pathology however, working with people’s adaptive behaviours such as resilience has not been a consideration. Using the resilience model as a conceptual framework healthcare professionals can engage with veterans towards resilience within the context of their personal experience of ill health. Using this contemporary framework for considering these aspects of care has the potential to facilitate resistance to stressors associated with being injured potentially averting quality of life impairments

    Effects of habitat and livestock on nest productivity of the Asian houbara Chlamydotis macqueenii in Bukhara Province, Uzbekistan

    Get PDF
    To inform population support measures for the unsustainably hunted Asian houbara Chlamydotis macqueenii (IUCN Vulnerable) we examined potential habitat and land-use effects on nest productivity in the Kyzylkum Desert, Uzbekistan. We monitored 177 nests across different semi-arid shrub assemblages (clay-sand and salinity gradients) and a range of livestock densities (0–80 km-2). Nest success (mean 51.4%, 95% CI 42.4–60.4%) was similar across four years; predation caused 85% of those failures for which the cause was known, and only three nests were trampled by livestock. Nesting begins within a few weeks of arrival when food appears scarce, but later nests were more likely to fail owing to the emergence of a key predator, suggesting foraging conditions on wintering and passage sites may be important for nest productivity. Nest success was similar across three shrub assemblages and was unrelated to landscape rugosity, shrub frequency or livestock density, but was greater with taller mean shrub height (range 13–67 cm) within 50 m. Clutch size (mean = 3.2 eggs) and per-egg hatchability in successful nests (87.5%) did not differ with laying date, shrub assemblage or livestock density. We therefore found no evidence that livestock density reduced nest productivity across the range examined, while differing shrub assemblages appeared to offer similar habitat quality. Asian houbara appear well-adapted to a range of semi-desert habitats and tolerate moderate disturbance by pastoralism. No obvious in situ mitigation measures arise from these findings, leaving regulation and control as the key requirement to render hunting sustainable

    Effects of PAG1 on Src-family kinase trafficking in neuroblastoma cells

    Get PDF
    The receptor tyrosine kinases (RTKs) are known to help regulate cell behaviors including differentiation, proliferation and migration during embryonic development of the neural crest. RTKs are believed to initiate signaling cascades in response to extracellular cues in part by controlling localization of Src-family kinases (SFKs). The scaffolding protein PAG1 binds SFKs and is believed to influence SFK activity and location within the cell by promoting interaction of SFKs with regulatory proteins and by drawing SFKs into different components of the endocytic pathway. By targeting the PAG1 gene in SH-SY5Y neuroblastoma cells with CRISPR/Cas9 plasmids, we created PAG1-mutant cell-lines in which a truncated, cytosolic form of PAG1 is expressed. Here I show that PAG1 mutants display increased proliferation. Furthermore I show that proliferation in PAG1 mutants was less sensitive to SFK inhibition than proliferation in wild-type cells. This was surprising because previously collected data had demonstrated that PAG1 mutants have higher levels of actively phosphorylated SFKs (pSFKs). SFKs may be increasingly targeted to multivesicular endosomes (MVEs) in PAG1 mutants, which can fuse with the plasma membrane releasing exosomes. Normally, SH-SY5Y cells release exosomes containing SFKs including LYN and FYN. Here, I show that exosomes released from PAG1 mutants contain lower levels of LYN and pSFKs than those from wild-type cells

    Peri-implant diseases: Consensus Report of the Sixth European Workshop on Periodontology

    Get PDF
    Issues related to peri-implant disease were discussed. It was observed that the most common lesions that occur, i.e. peri-implant mucositis and peri-implantitis are caused by bacteria. While the lesion of peri-implant mucositis resides in the soft tissues, peri-implantitis also affects the supporting bone. Peri-implant mucositis occurs in about 80% of subjects (50% of sites) restored with implants, and peri-implantitis in between 28% and 56% of subjects (12-40% of sites). A number of risk indicators were identified including (i) poor oral hygiene, (ii) a history of periodontitis, (iii) diabetes and (iv) smoking. It was concluded that the treatment of peri-implant disease must include anti-infective measures. With respect to peri-implant mucositis, it appeared that non-surgical mechanical therapy caused the reduction in inflammation (bleeding on probing) but also that the adjunctive use of antimicrobial mouthrinses had a positive effect. It was agreed that the outcome of non-surgical treatment of peri-implantitis was unpredictable. The primary objective of surgical treatment in peri-implantitis is to get access to the implant surface for debridement and decontamination in order to achieve resolution of the inflammatory lesion. There was limited evidence that such treatment with the adjunctive use of systemic antibiotics could resolve a number of peri-implantitis lesions. There was no evidence that so-called regenerative procedures had additional beneficial effects on treatment outcome

    Accounting for outliers and calendar effects in surrogate simulations of stock return sequences

    Full text link
    Surrogate Data Analysis (SDA) is a statistical hypothesis testing framework for the determination of weak chaos in time series dynamics. Existing SDA procedures do not account properly for the rich structures observed in stock return sequences, attributed to the presence of heteroscedasticity, seasonal effects and outliers. In this paper we suggest a modification of the SDA framework, based on the robust estimation of location and scale parameters of mean-stationary time series and a probabilistic framework which deals with outliers. A demonstration on the NASDAQ Composite index daily returns shows that the proposed approach produces surrogates that faithfully reproduce the structure of the original series while being manifestations of linear-random dynamics.Comment: 21 pages, 7 figure

    Effect of PAG1 on Src-Family Kinase Trafficking in Neuroblastoma Exosomes

    Get PDF
    SRC-family kinases (SFKs) are important in regulating cell-fate in neuroblastoma cells. PAG1, binds SFKs and helps regulate their activity by directing their movement within the cell. To better understand the role of PAG1, we created a line of mutant SH-SY5Y cells, called PAG1TM- cells, which express a truncated PAG1 protein, lacking a transmembrane domain. These cells still express high levels of mutant, cytosolic PAG1. We have found that PAG1TM- cells express a hyper-cancerous phenotype, including increased proliferation, and display higher global levels of active phosphorylated SFKs (pSFKs). The activity of pSFKs in PAG1TM- is still unknown. Protease protection experiments suggest that PAG1TM- cells may accumulate more pSFKs in multivesicular bodies (MVBs), however fractionation experiments have indicated that pSFKs primarily localize to early endosome and cytosol fractions. Once in MVBs, proteins may be recycled back to the plasma membrane or targeted to lysosomes for degradation. Alternatively, MVB cargo may be incorporated into exosomes and released by fusion of MVBs with the plasma membrane. SH-SY5Y cells, have been shown to release exosomes containing SFKs, including FYN and LYN. To determine if PAG1 is important for trafficking of SFKs into exosomes, I isolated exosomes from both wild-type (WT) and PAG1TM- SH-SY5Y cells and probed digested exosomes for SFKs. I found both LYN and pSFKs were greatly reduced in exosomes from PAG1TM- cells

    Assessing and Responding to Palliative Care Needs in Rural Sub-Saharan Africa: Results from a Model Intervention and Situation Analysis in Malawi

    Get PDF
    Introduction: Palliative care is rarely accessible in rural sub-Saharan Africa. Partners In Health and the Malawi government established the Neno Palliative Care Program (NPCP) to provide palliative care in rural Neno district. We conducted a situation analysis to evaluate early NPCP outcomes and better understand palliative care needs, knowledge, and preferences. Methods: Employing rapid evaluation methodology, we collected data from 3 sources: 1) chart review of all adult patients from the NPCP’s first 9 months; 2) structured interviews with patients and caregivers; 3) semi-structured interviews with key stakeholders. Results: The NPCP enrolled 63 patients in its first 9 months. Frequent diagnoses were cancer (n = 50, 79%) and HIV/AIDS (n = 37 of 61, 61%). Nearly all (n = 31, 84%) patients with HIV/AIDS were on antiretroviral therapy. Providers registered 112 patient encounters, including 22 (20%) home visits. Most (n = 43, 68%) patients had documented pain at baseline, of whom 23 (53%) were treated with morphine. A majority (n = 35, 56%) had ≥1 follow-up encounter. Mean African Palliative Outcome Scale pain score decreased non-significantly between baseline and follow-up (3.0 vs. 2.7, p = 0.5) for patients with baseline pain and complete pain assessment documentation. Providers referred 48 (76%) patients for psychosocial services, including community health worker support, socioeconomic assistance, or both. We interviewed 36 patients referred to the NPCP after the chart review period. Most had cancer (n = 19, 53%) or HIV/AIDS (n = 10, 28%). Patients frequently reported needing income (n = 24, 67%) or food (n = 22, 61%). Stakeholders cited a need to make integrated palliative care widely available. Conclusions: We identified a high prevalence of pain and psychosocial needs among patients with serious chronic illnesses in rural Malawi. Early NPCP results suggest that comprehensive palliative care can be provided in rural Africa by integrating disease-modifying treatment and palliative care, linking hospital, clinic, and home-based services, and providing psychosocial support that includes socioeconomic assistance
    corecore