Nonconventional fuels are gaining in importance due to limited availability of crude oil and rapid growth of the automotive industry and transportation sector which is resulting in increased emissions into the environment. Exhaust gases associated with combustion of fossil fuels used in transportation sector reduce air quality and thus have direct impact on human health. Biofuels are more environmentally friendly alternative fuels that are produced from animal or vegetable feedstocks. Developments of new and more effective analytical methods are increasing since the knowledge of the chemical composition represents challenge to analysts. In this paper, the most common and important chromatographic and spectroscopic methods in the analysis of feedstocks and nonconventional fuels are shown. The paper also presents the characteristic chromatogram and spectra of certain feedstocks for biofuel production and chromatogram of biodiesel recorded in the Laboratory for testing, water, hydrocarbons and materials (Central Testing Laboratory Department) in INA Petroleum Industry.
AbstractObjectivesTo investigate the additional value of transmural perfusion ratio (TPR) in dynamic CT myocardial perfusion imaging for detection of haemodynamically significant coronary artery disease compared with fractional flow reserve (FFR).MethodsSubjects with suspected or known coronary artery disease were prospectively included and underwent a CT-MPI examination. From the CT-MPI time-point data absolute myocardial blood flow (MBF) values were temporally resolved using a hybrid deconvolution model. An absolute MBF value was measured in the suspected perfusion defect. TPR was defined as the ratio between the subendocardial and subepicardial MBF. TPR and MBF results were compared with invasive FFR using a threshold of 0.80.ResultsForty-three patients and 94 territories were analysed. The area under the receiver operator curve was larger for MBF (0.78) compared with TPR (0.65, P = 0.026). No significant differences were found in diagnostic classification between MBF and TPR with a territory-based accuracy of 77 % (67-86 %) for MBF compared with 70 % (60-81 %) for TPR. Combined MBF and TPR classification did not improve the diagnostic classification.ConclusionsDynamic CT-MPI-based transmural perfusion ratio predicts haemodynamically significant coronary artery disease. However, diagnostic performance of dynamic CT-MPI-derived TPR is inferior to quantified MBF and has limited incremental value.Key Points• The transmural perfusion ratio from dynamic CT-MPI predicts functional obstructive coronary artery disease • Performance of the transmural perfusion ratio is inferior to quantified myocardial blood flow • The incremental value of the transmural perfusion ratio is limited
Introduction: Cigarette smoking is associated with severe health problems, especially cancers. In addition, cigarette smoking causes different genotoxic effects. Chromosome aberrations are one of well-known intermediate end points in carcinogenesis. The aim of this study was to compare frequencies of chromosome aberrations in peripheral blood lymphocytes between young smokers and non-smokes groups.Methods: The study was conducted with 30 smokers (average age 26.93 years) and 30 non-smokers (average age 26.96 years), and included the analysis of 100 metaphases per each blood sample. Differences in the arithmetic means of determined frequencies of chromosome aberrations were tested by two-tailed t-test for independent samples with the significance level of p < 0.05.Results: The results showed a significant increase in the frequencies of chromatid-type aberrations and total structural chromosome aberrations in smoker group. Frequencies of numerical aberrations did not differ significantly between two groups.Conclusions: This study confirmed genotoxicity of cigarette smoking and provided new evidence about its clastogenic activity.
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