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[en] Mineralized radioactive occurrences are often found in linear tectonic features across the world, which can easily be captured and traced from space imagery. The uranium-bearing silica veins in El Missikat Younger Granite plutons of the central Eastern Desert are some of the important occurrences of fracture-type uranium-mineralization in Egypt. The mapping of lineament networks provided the basis for correlation and analysis of the lineament network in relation to radioactive mineral occurrences in El Missikat area. The purpose of this study is to analyze the spatial distribution of lineaments extracted from space image as well as geological maps to establish cost-effective techniques in mineral exploration programs. Using this technique, first of all, a lineament map of the study area is prepared. During the second stage of the study, four analyses are applied for the lineaments evaluation. These are: 1) density analysis, 2) intersection density analysis, 3) length analysis, and 4) orientation analysis. The attempt made here revealed that the lineaments of ENE-WSW trend is dominant while its intersection with those of the NNWSSE, NW-SE and NNE-SSW trends within the younger granite will help in proceeding further detailed exploration. Moreover, lineament density indicated that mineralization is associated with the high density areas. Results of these analyses indicate definite structural interaction control for localizing radioactive mineralization in El-Missikat area and make it possible to delineate possible mineralized areas favorable for future prospectively
[en] Traditionally, the least-squares method is applied to separate the highly radioactive zones of gamma-ray spectrometric maps in order to find the normal radioactive background of the host rocks. In the present study, the regional background of gamma-ray spectrometric data was calculated by using the median instead of least-squares method which is based on the mean. The obtained least-squares do not properly fit due to the strong effect of the few outlier data points that are extremely high or low. The median is less affected by outliers and skewed data. If we reject these anomalous zones data, the proper fitting takes place. This study deals with using the median as a more suitable measure of central tendency for data classified on an ordinal scale. The mean is not suitable when the data include exceptionally high or low values because these have great influence on the outcome. The median was applied to the gamma-ray spectrometric (Total Count) survey data of El-Missikkat-Gidami area to separate the radioactive anomalous zones from the normal radiation of the host rocks
[en] Most image’ s interpreters are concerned with recognizing linear features in images. For geological purposes, faults, joints, features, dykes and geological contacts are the main linear features which must be interpreted. The linear features are formed by edges, where some edges are marked by pronounced differences in brightness and become ready recognized. This paper deals with satellite image edge detection techniques. Edge detection is the name for a set of mathematical methods which aim at identifying points in a satellite image at which the image brightness changes sharply or, more formally, has discontinuities. These points are typically organized into a set of curved line segments termed edges. Important features can be extracted from the edges of an image (e.g., corners, geological boundary, linesand curves). In this paper, a novel edge detection technique which computes edges of satellite image using two dimensional (2D) design digital filter is presented and applied on Gabal Gattar granitic batholith to enhance boundaries between granite and surrounded rocks in one hand, and between the granitic phases on another hand, as well as, enhance the shape of granitic masses, and faults, dykes, fractures cutting them. Here the proposed methodology is compared with other edge detectors. Filters (Sobel, Roberts, Prewitt, Canny and Log filters) as applied on G. Gattar granitic mass. This study reveals that the new proposed (Raafat filter) porttery the contacts and linear features more obvious than the other operators.
[en] BCG has been used for more than 30 years and is currently the most effective agent for non-muscle invasive bladder cancer therapy after transurethral resection. The high-grade T1 lesion treated by transurethral resection alone is reported to progress to muscle invasion in 30% to 50% of the patients. Until now, optimal treatment schedule and optimal dose have not been defined as the toxicity related to BCG therapy is significant. In this study we tried to evaluate the efficacy and toxicity of 60 mg intravesical BCG (Pasteur strain) therapy in patients with T1 transitional cell carcinoma of the bladder. Patients and Methods: From January 2000 till December 2007, 74 patients with single T1 transitional cell carcinoma (TCC) of the urinary bladder (grade 3 in 24 patients and grade 2 in 50 patients) were treated by complete transurethral resection followed by a 6-weeks course of 60 mg BCG intravesically. Follow-up ranged from 26- 96 months with median of 61 months. Results: Nine patients (12.1%) exhibited recurrence with muscle invasion after 6-18 months (5 with grade 3 tumors and 4 with grade 2), all were subjected to radical cystectomy and urine diversion. Whereas 19 patients (29.2%) showed recurrent T1 tumor after 16-45 months (7 with grade 3 tumors and 12 with grade 2) and were treated by TUR-T followed by a second 6-weeks course of 60 mg BCG intravesically. Recurrence index was 0.82/100 patients/month and the median tumor free period was 20 months. Regarding toxicity; irritative symptoms occurred in 24% of patients, fever in 9%, microscopic hematuria in 14%; which appeared to be significantly low when compared with the rates reported for higher doses of BCG. Conclusion: Intravesical therapy of 60 mg BCG is effective in prophylaxis against recurrence and progression of T1 TCC of the bladder. Decreasing the dose resulted