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[en] Remote sensing hyper spectral data has many applications especially in the field of , earth science. Utilization of this technology has shown a rapid increase in many areas of economic and scientific significance. Hyper spectral sensors capture the detailed spectral signatures that uniquely characterize a great number of diverse surface materials. Classification, clustering, and visualization of these very high dimensional signatures need untraditional methods. Different approaches for spectral image interpretation have been studied using Artificial Neural Networks (ANNs) and Support Vector Machines (SVM) to meet the challenge of high dimensionality. The study used SVMs for geological mapping of hyper spectral imagery at Abu Zenima area, western Sinai, Egypt, the hyper spectral data has been captured in 2003 by Hyperion instrument on the United States Geological survey (USGS) Earth Observing 1 (EO-I) satellite. Precisely the study compares between the use of SVMs and a neural network built on the concept of SVMs, this network uses the Kernel-Adatron algorithm with the Gaussian kernel for the process of training. The SVMs also uses the Gaussian kernel with different bandwidths to enhance the performance of the interpretation process; the results are compared in details. The Neural Network was trained with four data sets, the first consists of 11310 samples, gives recognition rate of 84%, the second has 22620 samples, recognition rate was 91.5%; the third has 33930 samples, recognition rate was 94.6%; finally the fourth has 45240 samples, recognition rate of 99.2%. The previous results fall in comparison with the results of SVMs which use two algorithms for training the first is the one against one algorithm which gave a recognition rate of 84% for the first data set, a recognition rate of 76.9% for the second data set, a recognition rate of 95.2% for the third one and 98.5% for the fourth one. and the other is one against many algorithms which gave a recognition rate of 84% for the first data set, a recognition rate of n.3% for the first data set, recognition rate of 94.6% for the second one and 98.5% for the third one
[en] Highlights: • Radiation damage and sensitization effects on TLD-700 dosimeters were discussed. • Attempts to reset the sensitivity of the dosimeters were made using two anneal types. • The radiation damage and sensitization effects vary depending on each peak. • A sensitization factor of ∼35 could be achieved using post-irradiation anneal. • Peak 7 sensitization factor of ∼22 was the dominant factor. The radiation damage effects and enhancement the thermoluminescence (TL) efficiency of LiF:Mg,Ti (TLD-700)dosimeters via sensitization method were discussed. Attempts to eliminate the effects of damage and sensitization were made using different types of annealing processes. The results showed that after irradiating the dosimeters with dose > 250 Gy of 60Co gamma source, damage effects were observed. The sensitivity of the total area under the curve was decreased by a factor of ∼0.5 after irradiation at a pre-test dose of 2 kGy. However, the effects of radiation damage on each glow-peak are different. The glow-peak 2 was the only peak that was not affected by the high-dose irradiation. It has been shown that the degree of the radiation damage effect is related to the maximum dose-response function, of the glow-peak. In general, significant radiation damage effects were observed for the glow-peaks of high . Post-irradiation anneal at 280 °C for 30 min causes dramatic effects on the shape of the glow-curve and as well as on the sensitivity of the dosimeters. An increasing by a factor of ∼35 in the sensitivity of the total area under the curve was observed at a pre-test dose of 2 kGy. Improving the sensitivity of peak 7 by a factor of∼22 was the dominant factor in increasing the sensitivity of the dosimeters. On the other hand, an increasing by factors of ∼2.5 and ∼4 was found for peaks 2 and 5 respectively. On the other hand, a decreasing by a factor ∼0.5 was observed for peaks 3 and 4. At pre-test dose levels >250 Gy, a very strange and high intensity tail was observed in the high-temperature region of the glow-curves. The readout anneal was not enough to remove this tail. While, the furnace anneal could eliminate the sensitization effects but not the radiation damage effects on the sensitivity of the dosimeters.
[en] Glasses with composition [xWO-(25-x)-ZnO-20NaO-55BO where x = 0, 5, 10, 15 and 20 mol. %] were prepared by melt quenching method. The amorphous state of the current glass samples was checked by X-ray diffraction (XRD). The measured density and calculated molar volume of all prepared samples were found to increase with the replacement of the lighter ZnO by the heavier of WO. The network structure of the present glasses was studied using the infrared (IR) and Raman spectroscopic techniques. IR and Raman results show that the structure of the samples is BO and BO units located in several structural groups with W-O-W units. The decreasing of the band gap energy values by the introducing of WO showed that the creation increases of the number of non-bridging oxygens in the structure of glass. All results showed that the parameters were dependent upon the dopant concentration of WO in the prepared glasses.
[en] Hepcidin, a key regulator of iron metabolism, is synthesized by the liver. Hepcidin binds to the iron exporter ferroportin to regulate the release of iron into plasma from macrophages, hepatocytes, and enterocytes. Aim: To study hepcidin expression in liver tissue of patients with hepatocellular carcinoma (HCC), chronic hepatitis C (CHC) and normal human liver biopsies and to compare its level with serum and liver iron indices. Patients and Methods: Liver biopsies from 66 patients (36 HCC and 30 CHC) were analysed as well as normal human liver biopsies obtained from 20 healthy liver transplant donors as a control group. Liver function tests, AFP, hepatitis markers, HCV-RNA levels, hemoglobin concentration and serum iron parameters were analyzed. Hepcidin mRNA was quantified in all liver biopsies of patients and controls by real-time PCR. Liver iron concentration (LIC) was evaluated and hepatic iron index (HII) was calculated by dividing LIC in mmol/gm dry weight by the patient's age. Results: The mean level for hepcidin mRNA in HCC, CHC and healthy controls were 2351±505, 5735±2403 and 16308±2194 copies/ml, respectively; with significant decrease in cancerous (HCC) than non-cancerous (CHC) and control liver tissues. The level was significantly lower in patients with multiple tumour masses. Hepcidin mRNA had a significant positive correlation with synthetic function of the liver (serum albumin and prothrombin concentration) and haemoglobin. In contrast, hepcidin mRNA was negatively correlated with parameters of iron stores as (serum ferritin and HII) and grade of liver fibrosis in both patient groups. Conclusion: The expression of hepcidin mRNA is decreased in liver tissues of CHC patients and more suppressed in the liver tissues of patients with HCC, suggesting that hepcidin expression appears to be appropriately responsive to iron status and disease progression in cirrhosis and hepato carcinogenesis.