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INCREASED EXPRESSION OF TOLL-LIKE RECEPTOR 4 IN HEPATOCELLULAR CARCINOMA-ITS CLINICOPATHOLOGICAL SIGNIFICANCE
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ATP release from bladder urothelium and serona in a rat model of partial bladder outlet obstruction
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A novel ZC4H2 gene mutation, K209N, in Japanese siblings with arthrogryposis multiplex congenita and intellectual disability： characterization of the K209N mutation and clinical findings
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Spatial distribution and mobility of metals and arsenic in river water and river bed sediments affected by copper mining activities in eastern Serbia
Get PDF秋田大学博士（工学）Contamination of river water and river bed sediments caused by copper mining is a serious problem in many regions of the world. The main cause of contamination is generation of acid mine drainage (AMD) by weathering of sulfide minerals in overburden and flotation tailings. The processing of copper ores may generate additional quantities of wastewater. Flotation reagents that are used for mineral processing of copper ore may also cause adverse effects in aquatic environment. There are two copper mining areas in eastern Serbia, located around towns of Bor and Majdanpek. Mining operations in Bor and Majdanpek started in 1903 and 1961, respectively, and are still continuing. Numerous open pits, underground mines, overburden and flotation tailing ponds are present in both mining areas. However, copper smelter and refining facility is present only in Bor. The aim of this PhD thesis is to determine spatial distribution and mobility of metals and arsenic in river water and river bed sediments that were affected by mining activities in eastern Serbia.
Field survey for creation of geochemical maps was conducted in 2015 and early 2016. Total number of river water and river bed sediment samples was 198 and 181, respectively, with average sampling density of 1 sample per 42 and 46 km², respectively. Spatial distribution and mobility of 9 elements (Al, Mn, Fe, Ni, Cu, Zn, As, Cd, and Pb) in river water and river bed sediments were considered. Additional field surveys for determination of seasonal variation of concentrations of metals and arsenic were carried out in September 2016, February 2017, and August 2017.
Geochemical maps, histograms and cumulative probability (CP) diagrams were created for 9 elements in river water and river bed sediments from eastern Serbia. Variations of background and threshold concentrations were determined from histograms and CP diagrams. Spatial distribution of elements was determined from geochemical maps. Grouping of data points on histograms, CP diagrams and geochemical maps indicated patterns that were considered in detail. Minimum, median, mean, maximum, mean–2σ and mean+2σ values for 9 elements were calculated, and threshold values that separate background and anomalous concentrations were obtained from the brakes of slope on CP diagrams. Concentration of Mn was decreased in river bed sediments that were in contact with acidic river water because of dissolution caused by acidic pH value. Higher concentrations of Ni were found in an area that consists of ultramafic rocks. High concentrations of Cu, Zn, As, Cd and Pb were found in river bed sediments downstream from Bor and Majdanpek copper mines; however, those concentrations were higher downstream from Bor copper mines. There were no anomalous values of Al in river bed sediment. Higher concentrations of Fe were found in the region of Timok Magmatic Complex that consists of upper Cretaceous andesitic rocks. Concentration of Fe was also high in river bed sediments of Bor and Bela Rivers due to presence of Fe-rich minerals (pyrite, fayalite, magnetite) that originated from flotation tailings.
Water of rivers downstream from Bor copper mines was acidic. Geochemical maps of total and dissolved concentrations of metals and arsenic in river water showed that rivers downstream from Bor and Majdanpek copper mines were contaminated. Higher concentrations of metals and arsenic were more frequently found in water of rivers downstream from Bor copper mines. Metallurgical facilities in Bor had the largest impact on Bor River by discharging about 400 t of Cu per year through highly acidic wastewater (pH = 2.6). The highest measured concentrations of Cu in river water and sediments were 40 mg/L and 1.6%, respectively. Dissolution of calcite from limestone bedrock and a high concentration of bicarbonate ions in natural river water (about 250 mg/L) enhanced the neutralization of acidic river water and subsequent precipitation of metals and arsenic on the river bed. Decreases in the concentrations of Al, Fe, Cu, As, and Pb in river water were mainly due to precipitation on the river bed. On the other hand, dilution played an important role in the decreases in concentrations of Mn, Ni, Zn and Cd.
Instead of remediation of contaminated river bed sediments downstream from Bor mining area, natural attenuation of metals and arsenic should be monitored. However, in order to enhance the processes of natural attenuation, removal of sources of contaminanation is necessary
Ore Genesis and Geochemical Characteristics of Carbonate-hosted Talc Deposits in Nangarhar Province, Afganistan.
Get PDF秋田大学博士（資源学）Talc occurs as economic deposits in amphibolite facies metamorphosed dolomite marble and magnesite rocks in the Spinghar Fault Block in Afghanistan. This block is composed of various Proterozoic gneisses, schists, quartzites, marbles and amphibolites metamorphosed to amphibolite facies which were intruded by Early Cretaceous igneous rocks such as migmatite-granite and gabbro-monzonite-diorite. Eight deposits and two prospects were chosen from three areas. Six quarries and outcrops among ten from the western part i.e., Anarokas, Kherwasti, Dar, Janinaw, Kotikhel (Dawood mine and Noor mine), three from the middle part i.e., Wachalgad, Lesho, Sargare and one from the most eastern part i.e., Mamond dara in Spinghar Fault Block were studied. The objective of this study is to understand the talc mineralization and formation processes in these areas on the basis of field relations, petrography, X-ray diffractometry (XRD), X-ray fluorescence spectroscopy (XRF), inductively coupled plasma mass spectrometry (ICP-MS), scanning electron microscope energy-dispersive X-ray spectroscopy (SEM-EDX) and electron probe micro analysis (EPMA).
In this block, talc ore bodies occur parallel to subparallel to host magnesite rocks, dolomite marble and gneiss. Intrusive rocks such as dolerite and diorite cross cut the talc ore bodies, host carbonate rocks and gneiss, and are also parallel to sub parallel to the beddings of host carbonate rocks and talc ore bodies. Tremolite was observed with most of talc, and antigorite (serpentine) in the altered dolerite and host carbonate rocks. Quartz veins follow the gneissosity of gneiss all over the study areas. Quartz veins were cross cut by granitic rocks at Anarokas. Talc was mainly formed by alteration of magnesite and tremolite in Kherwasti, Anarokas, Dar, Wachalgad, Lesho and Sargare, while in Janinaw, Kotikhel and Mamond dara, talc was formed by alteration of dolomite and tremolite. Common mineral assemblages in the study area of talc ores are (a) talc + magnesite, (b) talc + tremolite, in magnesite rocks (c) magnesite ± olivine and (d) magnesite + antigorite in Dar, Anarokas and Kherwasti, (e) talc + magnesite , in talc ores and (f) dolomite + calcite + tremolite in dolomite marble in Wachalgad, (g) talc + magnesite, in talc ores, (h) dolomite + tremolite ± talc in dolomite marble, and (i) hornblende + quartz + plagioclase in amphibolites in Lesho and Sargare, (j) talc + dolomite, in talc ores, (k) tremolite + dolomite in dolomite marble and (l) quartz + talc in quartz veins in Kotikhel and Janinaw, and (m) dolomite + talc + quartz ± calcite, in host dolomite marble (n) quartz + microcline + muscovite + biotite + allanite in gneiss in Mamond dara, and (o) quartz + muscovite + biotite in gneiss in Anarokas, Wachalgad and Kotikhel. On the basis of the mineral assemblages, the formation temperatures of different minerals such as talc, tremolite and antigorite were estimated. In Mamond dara, the temperature ranged from 360 to 460℃. In Anarokas, Dar and Kherwasti, the temperature was 380 to 460℃. In Janinaw and Kotikhel, it ranged from 405 to 500℃.
The SiO₂ contents of talc rocks from all deposits range from 56.1 to 65.1 wt% and carbonate rocks of Kotikhel are 16.2 wt%, those from Kherwasti range from 1.6 to 25.8 wt%, Anarokas range from 16.6 to 45.5 wt%, Dar range from 6.9 to 8.9 wt%, Wachalgad range from 5.6 to 22.2 wt%, Lesho are 31.0 wt%, Sargare range from 9.6 to 13.9 wt% and Mamond dara range from 10.9 to 15.7 wt%. It is evident that SiO₂ content increased to form talc from magnesite rocks and dolomite marble. The whole-rock MgO contents of those range from 30.2 to 35.5 wt% and 27.1 wt%, from 25.1 to 46.3 wt%, from 37.3 to 47.7 wt%, from 43.7 to 46.0 wt%, 23.1 to 53.5 wt%, 37.5 wt%, 26.2 to 48.1 wt%, and 19.3 to 21.9 wt%, respectively. The whole-rock CaO contents of talc rocks and magnesite rocks of all deposits are less than 1 wt%, while those of dolomite marbles of Kotikhel, Kherwasti, Wachalgad, Sargare and Mamond dara range from 17.0 to 33.5 wt%. The ƩREE contents of talc rocks, magnesite rocks and dolomite marbles in Wachalgad and Sargare are 0.4, 1.3, 3.5 ppm and 2.1, 1.7 and 6.6 ppm respectively. The ƩREE contents of talc rocks and magnesite rocks in Kherwasti range from 0.2 to 1.2 ppm, 0.7 to 18.6 ppm respectively, in Anarokas 0.5 ppm, 1.0 to 4.2 ppm respectively, in Dar from 0.2 to 0.8 ppm, 1.1 to 4.7 ppm respectively and in Lesho 2.6 ppm and 13.0 ppm respectively. The ƩREE contents of talc rocks and dolomite marble in Kotikhel are 0.12 ppm and 14.0 ppm respectively, in Janinaw from 0.08 to 6.6 ppm and 2.5 ppm respectively, while in Mamond dara it ranges from 0.04 to 3.2 ppm and 23.5 ppm respectively. EPMA analysis of carbonate minerals from all deposits shows that dolomite and magnesite compositions are close to the ideal composition with FeCO₃ ranging from 0.2 to 0.6 wt% and from 0.2 to 0.5 wt%, and MnCO₃ ranging from 0.02 to 0.06 wt% and from 0.01 to 0.09 wt%, respectively. The chemical compositions of talc and tremolite slightly deviate from ideal compositions with FeO, Na₂O, K₂O, MnO, Al₂O₃, TiO₂ and Cr₂O₃ contents less than 1 wt%. Concentrations of Al, Ta, Th, Cr, Ni, Co and ƩREE in talc ores and carbonates rocks are comparatively very low with mafic and ultramafic rocks, so inconsistent with mafic and ultramafic rocks protolith. Therefore, the metamorphosed sedimentary carbonate rocks were likely the protolith of talc ores. Magnesium has been derived from pre-existing Mg-rich carbonate host rocks, i.e., magnesite and dolomite marbles
Elevation of Serum Acid Sphingomyelinase Activity in Children with Acute Respiratory Syncytial Virus Bronchiolitis.
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An Investigation of Molecular Lesions in Two Japanese Families with Familial Paroxysmal Kinesigenic Dyskinesia.
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Clinical characteristics of Lynch-like cases collaterally classified by Lynch syndrome identification strategy using screening in endometrial cancer
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