104 research outputs found

    Experimental and computational study on dynamic analysis of cracked simply supported structures under moving mass

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    In this study, the influences of crack parameters like crack location from the left end, crack height, number of cracks and the magnitude of mass and the velocity of the transit load on the vertical displacements of the cracked simply supported beams subjected to transit mass are investigated. The transverse open cracks with numerous damage scenerios are considered for the mathematical modelling of the system. The governing equations of motion for the system have been obtained and the equations have been solved by the help of Duhamel integral technique. The theoretical formulation has been exemplified with numerical studies. By utilizing ANSYS Workbench 2020, transient  structural analysis has been carried out. The mode shapes and the frequency ratios of damaged simply supported beam have also been determined.  To validate the numerical and FEM models, the experiments with damaged beams have been carried out in the laboratory. It has been proven that the results of the theoretical and FEM models are well convergent with the experimental data. The results gathered from the numerical analysis, FEA as well as experimental study have been presented with comparative graphs and tables. The outcomes of the examinations have been interpreted in the conclusions part. It has been observed that subject parameters are of considerable significance on the time dependent response of the cracked beams

    Biomarker-based asthma phenotypes of corticosteroid response

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    BackgroundAsthma is a heterogeneous disease with different phenotypes. Inhaled corticosteroid (ICS) therapy is a mainstay of treatment for asthma, but the clinical response to ICSs is variable.ObjectiveWe hypothesized that a panel of inflammatory biomarkers (ie, fraction of exhaled nitric oxide [Feno], sputum eosinophil count, and urinary bromotyrosine [BrTyr] level) might predict steroid responsiveness.MethodsThe original study from which this analysis originates comprised 2 phases: a steroid-naive phase 1 and a 28-day trial of ICSs (phase 2) during which Feno values, sputum eosinophil counts, and urinary BrTyr levels were measured. The response to ICSs was based on clinical improvements, including a 12% or greater increase in FEV1, a 0.5-point or greater decrease in Asthma Control Questionnaire score, and 2 doubling dose or greater increase in provocative concentration of adenosine 5′-monophosphate causing a 20% decrease in FEV1 (PC20AMP). Healthy control subjects were also evaluated in this study for comparison of biomarkers with those seen in asthmatic patients.ResultsAsthmatic patients had higher than normal Feno values, sputum eosinophil counts, and urinary BrTyr levels during the steroid-naive phase and after ICS therapy. After 28-day trial of ICSs, Feno values decreased in 82% of asthmatic patients, sputum eosinophil counts decreased in 60%, and urinary BrTyr levels decreased in 58%. Each of the biomarkers at the steroid-naive phase had utility for predicting steroid responsiveness, but the combination of high Feno values and high urinary BrTyr levels had the best power (13.3-fold, P < .01) to predict a favorable response to ICS therapy. However, the magnitude of the decrease in biomarker levels was unrelated to the magnitude of clinical response to ICS therapy.ConclusionA noninvasive panel of biomarkers in steroid-naive asthmatic patients predicts clinical responsiveness to ICS therapy

    Measurement of the total antioxidant response using a novel automated method in subjects with nonalcoholic steatohepatitis

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    BACKGROUND: Oxidative stress, an increase in oxidants and/or a decrease in antioxidant capacity, is one of the potential biochemical mechanisms involved in the pathogenesis of nonalcoholic steatohepatitis. We aimed to investigate the total antioxidant response using a novel automated method in nonalcoholic steatohepatitis subjects. As a reciprocal measure, we also aimed to determine total peroxide level in the same plasma samples. METHODS: Twenty-two subjects with biopsy proven nonalcoholic steatohepatitis and 22 healthy controls were enrolled. Total antioxidant response and total peroxide level measurements were done in all participants. The ratio percentage of total peroxide level to total antioxidant response was regarded as oxidative stress index. RESULTS: Total antioxidant response of subjects with nonalcoholic steatohepatitis was significantly lower than controls (p < 0.05), while mean total peroxide level and mean oxidative stress index were higher (all p < 0.05). In subjects with nonalcoholic steatohepatitis, fibrosis score was significantly correlated with total peroxide level, total antioxidant response and oxidative stress index (p < 0.05, r = 0.607; p < 0.05, r = -0.506; p < 0.05, r = 0.728, respectively). However, no correlation was observed between necroimflamatory grade and those oxidative status parameters (all p > 0.05). CONCLUSION: Nonalcoholic steatohepatitis is associated with increased oxidant capacity, especially in the presence of liver fibrosis. The novel automated assay is a reliable and easily applicable method for total plasma antioxidant response measurement in nonalcoholic steatohepatitis

    Breath Formate Is a Marker of Airway S-Nitrosothiol Depletion in Severe Asthma

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    -nitrosothiols (SNOs), a class of endogenous airway smooth muscle relaxants. This deficiency results from increased activity of an enzyme that both reduces SNOs to ammonia and oxidizes formaldehyde to formic acid, a volatile carboxylic acid that is more easily detected in exhaled breath condensate (EBC) than SNOs. We therefore hypothesize that depletion of airway SNOs is related to asthma pathology, and breath formate concentration may be a proxy measure of SNO catabolism. (r = −0.39, p = 0.002, asthmatics only), and positively correlated with the NO-derived ion nitrite (r = 0.46, p<0.0001) as well as with total serum IgE (r = 0.28, p = 0.016, asthmatics only). Furthermore, formate was not significantly correlated with other volatile organic acids nor with inhaled corticosteroid dose.-nitrosothiols

    Determination of indoor radon levels at campuses of uskudar and Okan Universities

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    4th International Conference on Computational and Experimental Science and Engineering (ICCESEN) -- OCT 04-08, 2017 -- Kemer, TURKEY --Radon is the largest source of natural radiation all people exposed to. It can form in houses due to building materials or enters through cracks in walls, basement floors and with water used in bathroom showers and faucets. The buildings keep radon inside, where it accumulates and may become a health hazard if the building is not properly ventilated. Radon can be inhaled into the lung, and especially short-lived products of its disintegration can cause long-term internal exposure. In this study, indoor radon survey was carried out at several campuses of uskudar and Okan Universities by using AlphaGUARD active radon detector.WOS:0004788945000422-s2.0-8506819373

    Assessment of proofing of bread dough in the microwave oven

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    The effects of different proofing times in the microwave oven on the quality of microwave baked breads were investigated. The proofing height of the dough, specific volume and the firmness of the breads were found to be dependent on proofing time. When emulsifiers were added, the optimum proofing condition in the microwave oven was found to be 6 minutes at 10% power. The effects of different emulsifiers on the properties of the dough and, the volume and the firmness of the microwave-baked breads were compared. DATEM, Lecimulthin M-45 and Purawave were the three emulsifiers used. Purawave was found to be the most effective emulsifier on bread quality

    Effects of different formulations on the quality of microwave baked breads

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    Effects of different amounts of gluten, fat, emulsifier. and dextrose on the quality of breads baked in the microwave oven were investigated. Response surface methodology was used to optimize the formulation of microwave baked breads. Firmness, specific volume, and weight loss of the breads were determined. Breads formulated with low gluten flour were softer and had higher volume. Volume of these breads can be comparable with the volume of conventionally baked breads. For breads formulated with flour containing low gluten, the increase in fat and emulsifier contents decreased the firmness and increased the specific volume of breads. Fat. emulsifier, and dextrose contents were found to be the significant factors to reduce the weight loss of microwave baked breads

    The usefulness of GST lsoenzymes as markers of malignancy in urinary cytology

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    This study investigated the usefulness of GST lsoenzymes immunostaining as an early marker of malignancy in urinary cytology. They are also correlated with cytopathology diagnosis. In this study, the slides from 22 patients of benign urinary cytology who have benign urinary diseases and 6 patients who have clinical diagnosis of bladder carcinoma were observed. The cytomorphological characteristics and the immunocytochemical expression of GST alpha (GSTA), pi (GSTP), mu (GSTM4), theta (GSTT 1) isoen2ymes were examined. Immunohistochemical examinations showed that the urothelial cancer cells had stronger staining intensity than the benign cells in 5 (83%) cases for GSTA, 5 (%83) cases for GSTP, 1(%17) case for GSTM4 and 4 (%67) cases for GSTT1. The atypical cells had stronger staining intensity than the benign cells in 10 (%45) cases for GSTA, 16 (%73) cases for GSTP, 12 (%55) cases for GSTM4 and 13(%59) cases for GSTT1. There was no significant difference in GSTA, GSTM4, GSTT1, GSTP expressions for benign, atypical and malign cells (p>0.05). In conclusion, GST lsoenzymes were not found to be markers of malignancy in urinary cytology. © IDOSI Publications, 2010

    Influence of fat content and emulsifier type on the rheological properties of cake batter

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    The effects of fat content and emulsifier type on the rheological properties of cake batter have been investigated by using a parallel-plate rheometer. The apparent viscosity of cake batter with five different fat concentrations (0, 12.5, 25, 37.5, and 50%) and two types of emulsifier, namely Purawave and Lecigran, was studied as a function of the shear rate. In addition, the time dependency of different cake formulations was investigated. It was found that cake batter with different fat concentrations and emulsifier types exhibited shear thinning and time-independent behavior. Experimental data provided a good fit for the power law model. The increase in fat content and addition of emulsifier caused a decrease in the apparent viscosity. The flow behavior index was not found to be dependent on the composition of cake batter
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