4,024 research outputs found

    Performance evaluation of a low cost processor with wireless connectivity

    Get PDF
    The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file viewed on (July 17, 2006)Includes bibliographical references.Thesis (M.S.) University of Missouri-Columbia 2005.Dissertations, Academic -- University of Missouri--Columbia -- Electrical engineering.This study shows the development and analysis of the connectivity of a wireless system using a low cost processor. First, we designed a system with two sensor processors and a server PC. Second, we developed two protocols; the Ethernet protocol and the Round Robin protocol. Third, we analyzed the system. It was discovered that the Ethernet protocol had a faster transmission time while the Round Robin protocol had fewer collisions. Finally, we measured the overhead and found it to occupy between 50 and 90% of the transmission and processing time. In addition, it was found that the measurement of the data error rate for the transmission through different environments such as steel and wooden doors and unobstructed openings can be ignored compared to walls, and floors which cause significant problems. The stamp processor is a low cost, but low data rate wireless sensor system

    Sleep Duration, Sleep Quality, and the Development of Nonalcoholic Fatty Liver Disease:A Cohort Study

    Get PDF
    INTRODUCTION: The longitudinal relationship between sleep duration, sleep quality, and the risk of nonalcoholic fatty liver disease (NAFLD) is unknown. We aimed to examine the association between sleep duration, sleep quality, and NAFLD development.METHODS: Using the Pittsburgh Sleep Quality Index, sleep duration and quality were evaluated for 143,306 NAFLD-free Korean adults with a mean age of 36.6 years, who were followed for an average of 4.0 years. Hepatic steatosis (HS) was assessed using ultrasonography and liver fibrosis by the fibrosis-4 index (FIB-4) or the NAFLD fibrosis score. Flexible parametric proportional hazard models were used to determine the hazard ratios (HRs) and 95% confidence intervals.RESULTS: There were 27,817 subjects with incident HS, of whom 1,471 had incident HS plus intermediate/high FIB-4. Multivariable-adjusted HRs (95% confidence intervals) for incident HS comparing sleep durations of ≤5, 6, 8, and ≥ 9 hours with 7 hours were 1.19 (1.14-1.23), 1.07 (1.04-1.10), 0.98 (0.94-1.02), and 0.95 (0.87-1.03), respectively. The corresponding HRs for incident HS plus intermediate/high FIB-4 were 1.30 (1.11-1.54), 1.14 (1.01-1.29), 1.11 (0.93-1.33), and 1.08 (0.71-1.63). The association between sleep duration and HS plus intermediate/high FIB-4 was inverse in individuals with good sleep quality but tended to be U-shaped in those with poor sleep quality. The results were similar if FIB-4 was replaced by the NAFLD fibrosis score.DISCUSSION: In young adults, short sleep duration was independently associated with an increased risk of incident NAFLD with or without intermediate/high fibrosis score, suggesting a role for inadequate sleep quantity in NAFLD risk and severity.</p

    Decrease in sleep duration and poor sleep quality over time is associated with an increased risk of incident non-alcoholic fatty liver disease

    Get PDF
    The impact of changes in sleep duration and sleep quality over time on the risk of nonalcoholic fatty liver disease (NAFLD) is not known. We investigated whether changes in sleep duration and in sleep quality between baseline and follow-up are associated with the risk of developing incident NAFLD. The cohort study included 86,530 Korean adults without NAFLD and with a low fibrosis score at baseline. The median follow-up was 3.6 years. Sleep duration and quality were assessed using the Pittsburgh Sleep Quality Index. Hepatic steatosis (HS) and liver fibrosis were assessed using ultrasonography and the fibrosis-4 index (FIB-4). Cox proportional hazard models were used to determine hazard ratios (HRs) and 95% confidence intervals (Cis). A total of 12,127 subjects with incident HS and 559 with incident HS plus intermediate/high FIB-4 was identified. Comparing the decrease in sleep duration of &gt;1 h, with stable sleep duration, the multivariate-adjusted HR (95% CIs) for incident HS was 1.24 (1.15–1.35). The corresponding HRs for incident HS plus intermediate/high FIB-4 was 1.58 (1.10–2.29). Comparing persistently poor sleep quality with persistently good sleep quality, the multivariate-adjusted HR for incident HS was 1.13 (95% CI, 1.05–1.20). A decrease in sleep duration or poor sleep quality over time was associated with an increased risk of incident NAFLD, underscoring an important potential role for good sleep in preventing NAFLD risk.</p

    Small anisotropy of the lower critical field and s±s_\pm-wave two-gap feature in single crystal LiFeAs

    Full text link
    The in- and out-of-plane lower critical fields and magnetic penetration depths for LiFeAs were examined. The anisotropy ratio γHc1(0)\gamma_{H_{c1}}(0) is smaller than the expected theoretical value, and increased slightly with increasing temperature from 0.6TcT_c to TcT_c. This small degree of anisotropy was numerically confirmed by considering electron correlation effect. The temperature dependence of the penetration depths followed a power law(\simTnT^n) below 0.3TcT_c, with nn>>3.5 for both λab\lambda_{ab} and λc\lambda_c. Based on theoretical studies of iron-based superconductors, these results suggest that the superconductivity of LiFeAs can be represented by an extended s±s_\pm-wave due to weak impurity scattering effect. And the magnitudes of the two gaps were also evaluted by fitting the superfluid density for both the in- and out-of-plane to the two-gap model. The estimated values for the two gaps are consistent with the results of angle resolved photoemission spectroscopy and specific heat experiments.Comment: 10 pages, 5 figure

    Aldo-keto reductases are biomarkers of NRF2 activity and are co-ordinately overexpressed in non-small cell lung cancer

    Get PDF
    BACKGROUND: Although the nuclear factor-erythroid 2-related factor 2 (NRF2) pathway is one of the most frequently dysregulated in cancer, it is not clear whether mutational status is a good predictor of NRF2 activity. Here we utilise four members of the aldo-keto reductase (AKR) superfamily as biomarkers to address this question. METHODS: Twenty-three cell lines of diverse origin and NRF2-pathway mutational status were used to determine the relationship between AKR expression and NRF2 activity. AKR expression was evaluated in lung cancer biopsies and Cancer Genome Atlas (TCGA) and Oncomine data sets. RESULTS: AKRs were expressed at a high basal level in cell lines carrying mutations in the NRF2 pathway. In non-mutant cell lines, co-ordinate induction of AKRs was consistently observed following activation of NRF2. Immunohistochemical analysis of lung tumour biopsies and interrogation of TCGA data revealed that AKRs are enriched in both squamous cell carcinomas (SCCs) and adenocarcinomas that contain somatic alterations in the NRF2 pathway but, in the case of SCC, AKRs were also enriched in most other tumours. CONCLUSIONS: An AKR biomarker panel can be used to determine NRF2 status in tumours. Hyperactivation of the NRF2 pathway is far more prevalent in lung SCC than previously predicted by genomic analyses
    corecore