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Eosinophil ETosis-mediated release of galectin-10 in eosinophilic granulomatosis with polyangiitis
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COMPARISON OF VIRTUAL UNENHANCED AND TRUE UNENHANCED ATTENUATION VALUES BY DUAL-ENERGY CT FOR DETECTING INDISTINCT LIVER METASTASES ON CONTRAST-ENHANCED CT
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Differentiating Between Primary Central Nervous System Lymphoma and Glioblastoma: The Diagnostic Value of Combining 18 F Fluorodeoxyglucose Positron Emission Tomography with Arterial Spin Labeling
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Effects of GLP-1 receptor agonist on changes in the gut bacterium and the underlying mechanisms
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Geochemical and stable isotope studies of groundwater and river water in the Bor and Majdanpek porphyry copper mining areas in Eastern Serbia: Implications for the environmental impact on groundwater
Get PDF秋田大学博士（理学）Contamination of water bodies is a large problem in many mining areas in the world. A similar problem exists in Eastern Serbia, where mining activities have been carried out for about 120 years. Currently, in Eastern Serbia, there are four active copper mines, three in the Bor mining area and one in the Majdanpek mining area. The long history of mining in the Bor mining area has led to serious environmental problems, which are most pronounced on water pollution downstream of the mining sites. This research aims to clarify the geochemistry of river water and groundwater in the study area and to estimate the environmental impact on groundwater in the Bor and Majdanpek mining areas.
River water of Bor River, Krivelj River and Bela River located in the Bor mining area showed acidic pH ranging from 2.9 to 5.1, from upstream to downstream direction, with high concentrations of SO42-, Fe, As, Cu and Mn. River water of Small Pek River and the upper reach of Pek River are characterized by weakly alkaline pH and high concentrations of SO42-, Fe, As, Cu and Mn, although lower than the concentrations of these components in river water in the Bor mining area. The acidic river water in the Bor mining area transports large quantities of heavy metals and arsenic downstream, including 6900 t/year of Fe, 42 t/year of As, 910 t/year of Cu and 187 t/year of Mn. On the other hand, the weakly alkaline river water in the Majdanpek mining area transports smaller quantities of heavy metals and arsenic downstream (160 t/year of Fe, 0.1 t/year of As, 6 t/year of Cu and 272 t/year of Mn). This indicates that the environmental impact in the Bor mining area is significantly larger than that in the Majdanpek mining area. However, concentrations of SO42-, Fe, As, Cu and Mn in Bela River in the Bor mining area have greatly decreased after mixing of acidic polluted water of Bela River with water of Timok River containing a high bicarbonate concentration. This fact suggests that river water in the study area including Bor and Majdanpek mining areas has sufficient capacity for neutralization.
Stable isotope ratios of groundwater are typical for the moderate continental climate. However, groundwater samples collected in mountainous areas are relatively depleted in δD and δ18O compared with samples that are collected in plain areas of the
study area. This difference is thought to be caused by the altitude effect due to the Rayleigh process, which means that precipitations enriched in stable isotopes, that form groundwater in the study area, will occur first in the plain areas, and going towards higher altitudes precipitations will become depleted in stable isotopes.
Groundwater in the study area is characterized by pH values ranging from 6.4 to 8.8 and a high concentration of HCO3-. The groundwater is Ca-Mg-HCO3-dominant type water. In general, groundwater from the study area has good quality with low content of trace elements, which are below maximum admissible concentrations according to the Serbian standard for drinking water. Trace elements that are mainly present in groundwater are Ba and Sr. Barium and strontium concentrations are especially high in limestone-rich areas.
To determine whether mining activities are causing groundwater pollution in the study area, geochemical maps were created and threshold values for discrimination of anomalous populations from background populations were estimated for Ca2+, SO42-, and 24 other components. Geochemical maps created for Ca2+ and SO42- show that groundwater with high concentrations of these components is found along polluted rivers downstream of the Bor mining area, especially in the area along the Bela River. The actual concentrations of Ca2+ and SO42- exceeded the threshold values, although the concentrations in some groundwater samples in the area downstream of the Bor mine were below the standard values. Pollution of the groundwater along the polluted rivers is therefore thought to have been caused by mining activities of the Bor mine. Elevated concentrations of the studied components in groundwater from the Majdanpek mining area were not detected.
Based on the mixing analysis between interstitial water present in tailings along strongly polluted rivers and unpolluted groundwater, it is thought that interstitial water in tailings along Bor River and Bela River is causing pollution of groundwater in the vicinity of those rivers. While river water does not directly affect groundwater in the study area.
Calcium and sulfate concentrations were shown to be good indicators for monitoring of early-stage groundwater pollution caused by mining activities in the
study area, this evaluation is mainly suitable for groundwater with a near-neutral pH. In addition to this, the evaluation method used in this study, which is based on geochemical maps, threshold values and mixing analysis considering geochemical reactions, is widely applicable to environmental assessment in mining areas
GLP-1 receptor signaling differentially modifies the outcomes of sterile vs. viral pulmonary inflammation in male mice
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Initial experience of high-dose helical tomotherapy for medically inoperable esophageal cancer patients
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Optimization and Governance of Reverse Supply Chain for E-waste Treatment
Get PDF秋田大学博士（工学）Development and optimization of reverse supply chain (RSC) for electronic waste (e-waste) treatment has attracted increasing interests worldwide due to the economic value and environmental influence of e-waste. RSC is generally defined as the series of activities required to retrieve a used product from a customer and either dispose of it or recycle/reuse it. Compared to informal RSC, formal RSC is usually used to refer the RSC that comply with environmental-friendly requirements for e-waste treatment. Due to the concerns of the adverse influence on environment and human health, it urges the development of formal RSC to replace the rampant informal RSC in most developing countries. Furthermore, a well-designed formal RSC is essential considering the inherent advantages of informal RSC. In this end, this study focuses on the development of formal RSC and its optimization and governance, in order to promote the proper and appropriate treatment of e-waste. The study pays major attention to the prominent problems practically encountered in formal RSC in China. Wherein the prominent problems are summarized as the suitable collection channel structure and facility layout of formal RSC, and channel coordination between formal and informal RSCs. Specifically, this study firstly ① explores the optimal formal channel structure from different aspects; then ② discusses and compares the effectiveness of different policies on formalizing the collector in informal RSC; finally ③ conducts location planning of recycling centers for waste mobile phones (WMPs) treatment in China. This study firstly focuses on the competitive formal and informal RSCs. By modelling the influence of collection efforts, green technology investment and the government subsidy, this study establishes three game theoretic models that corresponding respectively to three different dual-channel structures. These models are used to analyze the optimal collection strategy and channel structure of formal RSC under the competitive formal and informal RSCs, and indicate the optimal government subsidies. Then, this study considers the coordination of formal and informal RSCs for its benefits on e-waste treatment. A game theory model is built to analyze how to effectively promote the formalization of informal collectors. Based on the model, we discuss and compare the influences of four different policies (two subsidies and two penalties). Finally, the study pays attention to the development and rational layout of recycling centers in formal RSC. This study establishes several forecasting models to estimate and forecast the provincial WMPs of mainland China and develops a mixed-integer programming model for location planning of corresponding recycling infrastructures. Based on the theoretical models and related numerical analysis, several key findings are concluded. The study firstly analyzes the optimal formal channel structures from the perspectives of formal recycler, consumer and government respectively. It is concluded that there exists the conflict of interests when deciding the optimal formal channel structure. The results further indicate that formal recyclers should positively implement collection efforts in order to improve the collected quantity and the profit of the formal channel even they outsource collection activities to independent collectors. Besides, the optimal subsidies are calculated for different formal channel structures from the aspect of minimizing the profit of informal RSC. Thirdly, the study concludes that both the subsidy and penalty policies can promote the formalization of informal collectors. And there is no difference between the subsidy to informal collectors and formal recyclers (penalty on informal collectors or informal recyclers) regarding the change of recycling quantity. It is noteworthy that there exist the decremental effect of subsidy and the incremental effect of penalty on promoting formalization activity. Lastly, the study estimates the WMPs in all 31 provinces of mainland China from year 1992 to 2036. Through the location planning study, it indicates the concrete locations of recycling centers and the WMPs flows across provinces, and concludes that a total of 175 recycling centers are required for WMPs treatment in China in 2036. Accordingly, this study indicates major managerial implications for both the government and the recycler in formal RSC. The implications for the government include prudently designing and implementing policies, simplifying the supervision system and improving its responsiveness, and promoting the co-construction of recycling centers and cooperation on WMPs treatment across provinces in China. For formal recyclers, they are suggested to establish their own collection channel or to centralize other independent collection channels, to positively implement activities to promote consumers’ participation, and to establish its recycling centers following the planned locations. In summary, the whole study can benefit the development and optimization of RSC as follows. Firstly, the whole study can help maximize the economic profit of formal RSC and benefit the environment. Secondly, the study can help promote the collection rate of formal RSC through the optimized formal channel structure and the efficiently coordinated formal and informal RSCs. Thirdly, because of the optimized locations of recycling centers, the study can contribute to the rational layout of recycling centers in formal RSC