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It is a challenge to map large-gradient deformation over mining areas via current InSAR (interferometric synthetic aperture radar) techniques. To this end, we present a new method that is combined ...

Coal mining can create a variety of environmental, ecological, and land-use problems. Subsidence areas resulting from coal mining are a common and particularly difficult problem to manage. Despite much discussion in the academic literature as well as among local and international stakeholders, there is neither a uniform standard nor a universally accepted approach for selecting an appropriate governance model for a subsidence area. In particular, the lack of quantitative evaluation methods and excessive subjectivity represent key obstacles to the effective selection of governance models for subsidence areas. This paper proposes a selection framework for a coal mining subsidence governance model that integrates the analytic hierarchy process (AHP) and entropy weight method (EWM). The model comprehensively considers the settlement characteristics of the subsidence area, its geographic location, the water index, as well as the vegetation index. These variables are used as indicators to develop an evaluation framework upon which different subsidence zones can be quantitatively analyzed. The selection framework is demonstrated using examples from three subsidence areas in the Huainan and Huaibei mining areas in China, for which relevant data were collected and processed with the help of field surveys, remote sensing images, and subsidence prediction software. Applying the novel selection framework, the most suitable governance model for each subsidence area was obtained and determined to be consistent with the recommendations of an academic panel composed of multiple experts. The novel selection framework has high efficacy and potential to overcome the problem of subjectivity in the selection of governance models for coal mining subsidence areas. It is also envisaged that future incorporation of the selection framework into a user-friendly software package will significantly improve the efficiency with which suitable governance models for coal mining subsidence areas are selected.

To explore the sources and distribution characteristics of SO42− in the surface waters of the Linhuan mining area in Huaibei, river and surface water samples in subsidence and mine drainage locations in the study area were collected at different times. The conventional hydrochemical indexes and the eigenvalues of sulfur and oxygen isotopes were tested and analyzed. The results suggested the following: (1) The SO42− content showed seasonal changes: low-flow seasons > mid-flow seasons > high-flow seasons. (2) Based on δ34SSO4 and δ18OSO4 isotope analyses, the main source of SO42− was the dissolution of evaporite salt rocks in the stratum of the upstream area. The SO42− in the subsidence area was mainly from the river water supply, mine drainage and coal gangue leaching. The high concentration of SO42− in the mine drainage was mainly from the dissolution of evaporative salt rocks. (3) The calculation results of the ternary mixing model showed that the SO42− in the subsidence area water was affected by mine drainage and gangue leaching to different degrees. The results showed that the sulfate contribution proportion of the river water source to the subsidence area water was 35.8–65.9%; the sulfate contribution proportion of the mine drainage source to the subsidence area water was 2.0–26.6%; and the sulfate contribution proportion of the gangue leaching end source ranged from 16.3% to 56.9%. Coal mining activities had an important impact on the sulfate in the subsidence area water.

The most prominent source of Cu contamination in soils is metal mining and processing, partly since the Middle Age. However, coal mining and combustion can also cause (some) Cu contamination. We studied the distribution of Cu concentrations and isotope ratios in soils of the Huaibei coal mining area. The contribution of the coal mining and combustion to total Cu concentrations in soil was determined with a two-end-member mixing model based on the distinct δ

The Cd and Hg contents in soils can be elevated due to coal mining. To estimate the effects of these two heavy metals on soil enzymes and the key microbial groups, coal mine–affected agricultural soils were cultured for 30 days with Cd and/or Hg. Soil enzyme activities were measured by a colorimetric method, and microbial abundance was assessed according to real-time quantitative PCR analysis of the 16S rRNA and 18S rRNA genes. In addition, the microbial communities were analyzed by Illumina sequencing. Heavy metals inhibited soil enzyme activities. For example, both Cd and Hg decreased 25.52–34.89% of the soil catalase activity; the highest level of Hg (30 mg kg−1) decreased 76.50–89.88% of the soil urease activity and 85.60–92.92% of the soil dehydrogenase activity; and the soil acid phosphatase activity significantly decreased by 15.18–32.64% under all the levels of Cd and decreased 17.09–30.32% under the high levels of the Cd–Hg combination (> 3 mg kg−1). In addition, increased Cd levels affected bacterial number more than fungal abundance; however, addition of Hg alone decreased the bacterial number but increased the fungal abundance. Furthermore, the bacterial communities but not fungal communities were altered by heavy metals. A total of 23 highly sensitive genera and 16 highly resistant genera were identified. The sensitive genera were assigned to Actinobacteria, Acidobacteria, Candidate division WS3, Chloroflexi, Gemmatimonadetes, Proteobacteria, and Thermotogae, while the resistant genera were affiliated to Bacteroidetes and Proteobacteria. Soils containing the highest level of the combination of Cd and Hg exhibited the lowest soil enzyme activities; bacterial communities were more sensitive to heavy metal contamination than fungi.

Many studies have been carried out on the water environment in coal-mining subsidence area, which have mainly focused on the two aspects of nitrogen and phosphorus as well as heavy metal pollution in water. However, little attention has been paid to the problem of sulfate pollution. The surrounding conditions of subsidence area in Linhuan are complex, and there are a large number of coal gangue accumulation and coal mining activities. The sulfate pollution in water body is serious, while the specific sulfate source remains unclear. In the present study, the mining subsidence area in Linhuan, Huaibei was selected as the main study area, and 21 water samples were systematically collected from river water, subsidence area water and mine drainage. The conventional hydrochemical indexes were analyzed, and sulfur and oxygen isotopes were used to trace sources of sulfate in river water and subsidence area water. Our results showed that the total dissolved solid content was high in surface water, the hydrochemical type of Huihe River water was mainly Na

The external nitrogen load input caused by human activities exacerbates the eutrophication process of aquatic ecosystems in mining areas, causing water quality problems. However, knowledge of the sources and environmental behavior of nitrate in the surface water of mining areas is still very limited. This study investigated the nitrate content and spatiotemporal variation characteristics of surface water in the Linhuan mining area, identified the sources and transformation processes of nitrate using isotopes and hydrochemistry, and evaluated the contribution rates of different potential nitrate sources based on a Bayesian mixing model. The nitrogen pollution in the surface water in the mining area seriously exceeded class Ⅴ of the Environmental Quality Standard of Surface Water of China (GB3838-2002). The NO3− content ranged from 0.87 to 3.41 mg/L, showing obvious seasonal and spatial differences. Isotope and NO3−/Cl− analysis indicated that nitrate in the subsidence area water (SAW) was mainly derived from chemical fertilizer (NF) and soil organic nitrogen (NS), while nitrate in the mainstream of the Huihe River water (HRW) was mainly derived from manure/sewage (MS). The nitrate in the tributary of the Baohe River water (BRW) was mainly derived from soil NS, and nitrification was a nitrogen conversion pathway in the soil. The results of the Bayesian mixing model showed that the main sources of nitrate in the BRW, HRW and SAW were NF (34.5%), MS (68.8%) and NF (40.8%) in the wet season, and NS (33.4%), MS (70.9%) and NF (58.1%) in the dry season, respectively. The results of this study provide a new integrated method for the identification of nitrate pollution sources in mining areas, and this method can be used to improve the biogeochemical information of nitrogen in the aquatic ecosystems of mining areas and help formulate relevant measures to reduce water nitrogen pollution.

The aim of the present study was to investigate the effect of different concentrations of mast cell chymase on the transforming growth factor (TGF)-β1/Smad signaling pathway in skin fibroblasts. Cultured skin fibroblasts were treated with various concentrations of chymase for different time periods. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to assess the rate of cell proliferation. In addition, protein expression in the fibroblasts was measured using western blot analysis. Chymase was shown to enhance the proliferation of skin fibroblasts following incubation for 48, 72 and 96 h (P

The present study assessed the existence of mast cell chymase in hypertrophic scars and determined whether chymase promotes fibrosis via the transforming growth factor (TGF)-β1/Smads signaling pathway. Five patients with hypertrophic scars and another five patients subjected to repair and reconstruction of other tissue defects were included in the present study. To detect the existence of mast cells and mast cell chymase in hypertrophic scars, immunohistochemistry was employed. To test the effect of chymase on TGF-β1, angiotensin, and type I and III collagen mRNA expression in isolated hypertrophic scar fibroblasts in vitro, reverse-transcription quantitative PCR was performed. To investigate how chymase affects TGF-β1, phosphorylated (P)-Smad2/3 as well as Smad4 and Smad7 protein expression, western blot analysis was used. Mast cell chymase was identified to promote the mRNA expression of TGF-β1, angiotensin, and type I and III collagen in hypertrophic scar fibroblasts in a time- and dose-dependent manner. Furthermore, treatment with 60 ng/ml mast cell chymase for 12 h led to the upregulation of TGF-β1, P-Smad2/3, Smad4 and Smad7 in hypertrophic scar fibroblasts. The present study demonstrated that mast cells and chymase are present in hypertrophic scars, and chymase promotes hypertrophic scar fibroblast proliferation and collagen synthesis by activating the TGF-β1/Smads signaling pathway.

Mast cells play a significant role in the late stage of wound healing following burn injuries. In the present study, the possible role of mast cell chymase in burn wound healing was examined using a mast cell membrane stabilizer, ketotifen, in hamsters. A total of 28 hamsters were randomly divided into two groups (n=14), termed as the control and ketotifen groups. A deep partial-thickness burn injury was made on the back skin of the hamsters. The control group was orally administered physiological saline (1 ml) and the ketotifen group was orally administered ketotifen (4 mg/kg) once daily, two days prior to and two days subsequent to the burn. The results showed that concentrations of angiotensin II (Ang II), TGF-β1, collagens I and III and interleukin (IL)-1β were significantly decreased in the ketotifen group compared with those in the control group. However, there was no significant difference in fibroblast apoptosis between the two groups. The release of mast cell chymase was inhibited by the mast cell membrane stabilizer ketotifen. Taken together, these results suggest that mast cell chymase may participate in the process of burn wound healing. Chymase may therefore be a promising therapeutic target for the treatment of burn wounds.

The present study aimed to investigate the changes in the expression levels and activity of mast cell chymase in the process of burn wound healing in a hamster model of deep second-degree burn. The hamster model was established by exposing a ~3 cm diameter area of bare skin to hot water (75°C) for 0, 6, 8, 10 or 12 sec. Tissue specimens were collected 24 h after burning and histological analysis revealed that hot water contact for 12 sec was required to produce a deep second-degree burn. Quantitative polymerase chain reaction and a radioimmunoassay were used to the determine changes in chymase mRNA expression levels and activity. The mRNA expression levels and activity of chymase were increased in the burn wound tissues when compared with the normal skin. However, no statistically significant differences were observed in mast cell chymase activity amongst the various post-burn stages. Chymase mRNA expression levels peaked at day 1 post-burn, subsequently decreasing at days 3 and 7 post-burn and finally increasing again at day 14 post-burn. In summary, a hamster model of deep second-degree burn can be created by bringing the skin into contact with water at 75°C for 12 sec. Furthermore, the mRNA expression levels and activity of chymase in the burn wound tissues increased when compared with those in normal skin tissues.

Reverse medial upper arm flap is usually utilized in the reconstruction of defects in soft tissues of head and facial skin and is with good clinical efficacy. However, it has not been used in the reconstruction of ripped defects. In this study, we used the reverse tubular medial upper arm flap to repair the ripped facial defects. The reverse tubular skin flap from the medial upper arm was longitudinally cut into two parts. One part was used for the reconstruction of ripped facial defects. The other part was used as inner lining to repair the defects of mucosa. Using this method, 3 patients with ripped facial defects were successfully repaired. Thus the reverse tubular medial upper arm flap was successfully used in the reconstruction of ripped facial defects with little surgical trauma, simple manipulation of the operation, increased success rate of the operation and reduced incidence of complications.

It was previously demonstrated that the main cause behind keloid formation may be keloid fibroblast abnormalities, which are closely associated with the microenvironment of the keloid lesion. The post-traumatic and chronic inflammation of the keloid lesion area suggest that inflammatory mediators play an important role in the keloid microenvironment and are crucial for keloid fibroblast abnormalities. In this study, we hypothesized that the mechanism underlying keloid formation may involve the continuous upregulation of proinflammatory gene expression in keloid lesions. This hypothesis may explain the inflammatory response, invasive growth and recurrence following resection of keloids, as well as the selective localization of keloids in specific parts of a patient's body and the differences in localization among different patients.

Wound healing is a complex process, with various intracellular molecules and cytokines involved. Chymase is a chymotrypsin-like serine protease originally found to be a mast cell protease. In this study, to further investigate the role of chymase in the process of wound healing, the effects of chymase on cell proliferation and cytokine activation in human skin fibroblasts were determined. To determine cell proliferation, MTT assay was employed. The cells were harvested and total proteins were extracted and detected by western blotting. It was found that in vitro cell treatments with chymase led to dose-dependent increases of skin fibroblast proliferation. Moreover, the treatment of cells with chymase for 6 h induced dose-dependent increases in the expression levels of transforming growth factor (TGF)-β1 and interleukin (IL)-1β, although higher doses (120 ng/ml for TGF-β1; 60 and 120 ng/ml for IL-1β) did not facilitate the detected cytokine expression. In addition, treatment for longer periods of time (12 or 24 h) did not increase TGF-β1 or IL-1β expression. The results from our study will strongly facilitate the understanding of the roles of chymase in the process of wound healing.

Infantile skin hemangiomas (ISHs), the most common tumor of infancy, is a kind of benign vascular tumors that are characterized by their dramatic growth after birth, by diffusing proliferation of immature endothelial cells, followed by a spontaneous involution phase. Existing therapeutic approaches have limited success and significant adverse effects of some treatment modalities due to the limitation of their use. Better understanding of the pathogenesis of ISH will enables the development of better therapeutic strategies. The mechanisms for the development of ISHs are not completely understood and their pathogenesis is just now being elucidated. We hypothesize that skin trauma-induced hypoxia triggers neovascularization, which encompasses both angiogenesis and vasculogenesis, leading to the formation of ISHs. Assuming the hypothesis correct, the paper is aimed at come up with a prophylaxis and therapy that prevent infants from both intrauterine and extrauterine trauma, and inhibit excessive neovascularization by some medicine to prevent the ISHs formation.