6 research outputs found

    Highway Lighting Test Bed on INDOT Facility (Off-Roadway)

    Get PDF
    According to the National Highway Traffic Safety Administration (NHTSA), during 2016 there were 7,277,000 vehicle crashes nationally. Among them, approximately 70% happened during the daytime and around 30% of crashes occurred during the nighttime. There were 11,375 nighttime fatal crashes that account for about 48% of total fatal crashes (23,714). Given the fact that only 25%–33% of the vehicle miles traveled (VMT) occur at night, the above statistics indicate that the nighttime crash fatality rate is much higher and nighttime crashes are usually more severe compared to daytime crashes. Providing lighting on roadways is one of the proven safety countermeasures for preventing crashes and reducing fatalities. In particular, lighting at roadway intersections can reduce vehicle crashes by 10% to 26%. Currently, to conduct lighting field testing, INDOT is using several in-service highways, intersections, interchanges, and rest areas. These locations require traffic control and lane closures, which raises safety concerns and causing inconvenience to the public. In addition to the cost and safety concerns, during the evaluation period the new luminaires being tested actually functioned as lighting sources in place of the existing luminaires that were removed in order to install the new luminaires. This means that the new luminaries were used for roadway lighting at the test sites even before they were proven to meet the roadway lighting requirements. To eliminate traffic control and potential safety concerns, it was proposed to create test beds for field evaluating and to verify the performance of new lighting technologies and luminaires in a controlled, standard setting. Through this study, two lighting test bed facilities were designed and constructed. Illuminance values of installed luminaires were manually measured by a remotely controlled electric cart and drone. The measured illuminance values were analyzed and the analysis indicated that the efficiency of illuminance measurement can be significantly improved by automated methods. An illuminance data repository model was developed to be an effective tool that can greatly facilitate data input and storage process. The use of this model will further increase the productivity of illuminance measurement at the lighting test beds

    Truck Traffic and Load Spectra of Indiana Roadways for the Mechanistic-Empirical Pavement Design Guide

    Get PDF
    The Mechanistic-Empirical Pavement Design Guide (MEPDG) has been employed for pavement design by the Indiana Department of Transportation (INDOT) since 2009 and has generated efficient pavement designs with a lower cost. It has been demonstrated that the success of MEPDG implementation depends largely on a high level of accuracy associated with the information supplied as design inputs. Vehicular traffic loading is one of the key factors that may cause not only pavement structural failures, such as fatigue cracking and rutting, but also functional surface distresses, including friction and smoothness. In particular, truck load spectra play a critical role in all aspects of the pavement structure design. Inaccurate traffic information will yield an incorrect estimate of pavement thickness, which can either make the pavement fail prematurely in the case of under-designed thickness or increase construction cost in the case of over-designed thickness. The primary objective of this study was to update the traffic design input module, and thus to improve the current INDOT pavement design procedures. Efforts were made to reclassify truck traffic categories to accurately account for the specific axle load spectra on two-lane roads with low truck traffic and interstate routes with very high truck traffic. The traffic input module was updated with the most recent data to better reflect the axle load spectra for pavement design. Vehicle platoons were analyzed to better understand the truck traffic characteristics. The unclassified vehicles by traffic recording devices were examined and analyzed to identify possible causes of the inaccurate data collection. Bus traffic in the Indiana urban areas was investigated to provide additional information for highway engineers with respect to city streets as well as highway sections passing through urban areas. New equivalent single axle load (ESAL) values were determined based on the updated traffic data. In addition, a truck traffic data repository and visualization model and a TABLEAU interactive visualization dashboard model were developed for easy access, view, storage, and analysis of MEPDG related traffic data

    Highway Lighting Test Bed on INDOT Facility (Off-Roadway)

    Get PDF
    SPR-4442According to the National Highway Traffic Safety Administration (NHTSA), during 2016 there were 7,277,000 vehicle crashes nationally. Among them, approximately 70% happened during the daytime and around 30% of crashes occurred during the nighttime. There were 11,375 nighttime fatal crashes that account for about 48% of total fatal crashes (23,714). Given the fact that only 25%\u201333% of the vehicle miles traveled (VMT) occur at night, the above statistics indicate that the nighttime crash fatality rate is much higher and nighttime crashes are usually more severe compared to daytime crashes. Providing lighting on roadways is one of the proven safety countermeasures for preventing crashes and reducing fatalities. In particular, lighting at roadway intersections can reduce vehicle crashes by 10% to 26%. Currently, to conduct lighting field testing, INDOT is using several in-service highways, intersections, interchanges, and rest areas. These locations require traffic control and lane closures, which raises safety concerns and causing inconvenience to the public. In addition to the cost and safety concerns, during the evaluation period the new luminaires being tested actually functioned as lighting sources in place of the existing luminaires that were removed in order to install the new luminaires. This means that the new luminaries were used for roadway lighting at the test sites even before they were proven to meet the roadway lighting requirements. To eliminate traffic control and potential safety concerns, it was proposed to create test beds for field evaluating and to verify the performance of new lighting technologies and luminaires in a controlled, standard setting. Through this study, two lighting test bed facilities were designed and constructed. Illuminance values of installed luminaires were manually measured by a remotely controlled electric cart and drone. The measured illuminance values were analyzed and the analysis indicated that the efficiency of illuminance measurement can be significantly improved by automated methods. An illuminance data repository model was developed to be an effective tool that can greatly facilitate data input and storage process. The use of this model will further increase the productivity of illuminance measurement at the lighting test beds

    SDH mutations, as potential predictor of chemotherapy prognosis in small cell lung cancer patients

    No full text
    Abstract Purpose Small cell lung cancer (SCLC) is an aggressive and rapidly progressive malignant tumor characterized by a poor prognosis. Chemotherapy remains the primary treatment in clinical practice; however, reliable biomarkers for predicting chemotherapy outcomes are scarce. Methods In this study, 78 SCLC patients were stratified into “good” or “poor” prognosis cohorts based on their overall survival (OS) following surgery and chemotherapeutic treatment. Next-generation sequencing was employed to analyze the mutation status of 315 tumorigenesis-associated genes in tumor tissues obtained from the patients. The random forest (RF) method, validated by the support vector machine (SVM), was utilized to identify single nucleotide mutations (SNVs) with predictive power. To verify the prognosis effect of SNVs, samples from the cbioportal database were utilized. Results The SVM and RF methods confirmed that 20 genes positively contributed to prognosis prediction, displaying an area under the validation curve with a value of 0.89. In the corresponding OS analysis, all patients with SDH, STAT3 and PDCD1LG2 mutations were in the poor prognosis cohort (15/15, 100%). Analysis of public databases further confirms that SDH mutations are significantly associated with worse OS. Conclusion Our results provide a potential stratification of chemotherapy prognosis in SCLC patients, and have certain guiding significance for subsequent precise targeted therapy

    Protection of Pancreatic β-Cells by Group VIA Phospholipase A2-Mediated Repair of Mitochondrial Membrane Peroxidation

    No full text
    Mitochondrial production of reactive oxygen species and oxidation of cardiolipin are key events in initiating apoptosis. We reported that group VIA Ca2+-independent phospholipase A2 (iPLA2β) localizes in and protects β-cell mitochondria from oxidative damage during staurosporine-induced apoptosis. Here, we used iPLA2β-null (iPLA2β−/−) mice to investigate the role of iPLA2β in the repair of mitochondrial membranes. We show that islets isolated from iPLA2β−/− mice are more sensitive to staurosporine-induced apoptosis than those from wild-type littermates and that 2 wk of daily ip administration of staurosporine to iPLA2β−/− mice impairs both the animals’ glucose tolerance and glucose-stimulated insulin secretion by their pancreatic islets. Moreover, the iPLA2β inhibitor bromoenol lactone caused mitochondrial membrane peroxidation and cytochrome c release, and these effects were reversed by N-acetyl cysteine. The mitochondrial antioxidant N-t-butyl hydroxylamine blocked staurosporine-induced cytochrome c release and caspase-3 activation in iPLA2β−/− islets. Furthermore, the collapse of mitochondrial membrane potential in INS-1 insulinoma cells caused by high glucose and fatty acid levels was attenuated by overexpressing iPLA2β. Interestingly, iPLA2β was expressed only at low levels in islet β-cells from obesity- and diabetes-prone db/db mice. These findings support the hypothesis that iPLA2β is important in repairing oxidized mitochondrial membrane components (e.g. cardiolipin) and that this prevents cytochrome c release in response to stimuli that otherwise induce apoptosis. The low iPLA2β expression level in db/db mouse β-cells may render them vulnerable to injury by reactive oxygen species
    corecore