With increases in the mining depth and area in the Ordos coal field, the failure law of the super thick sandstone in the Zhidan group leads to frequent disasters, such as rock bursts and mine ...earthquakes, which have become a significant issue, restricting large-scale continuous mining. To adequately understand the movement mechanism of the super-thick and weakly cemented overburden, and to promote the large-scale mining of the coal resources under it, this study analyzes the physical and mechanical properties, along with the microstructural characteristics, of the weakly cemented overburden of the Yingpanhao Coal Mine through mechanics tests, scanning electron microscope tests (SEM) and hydrolysis experiments. A two-dimensional discrete element model of the survey region is then built to explore the temporal and spatial evolution laws of the overburden failure. The results show that, even though poorly cemented strata such as the Cretaceous Zhidan group sandstone and the Zhiluo group sandstone are weak in lithology, their unique mineral composition and microstructural characteristics give them a greater rigidity when their thickness reaches a certain value. The surface subsidence exhibits a sudden increase, and the dynamic disaster range of the overlying strata is wide when deep multi-face mining was carried out under the super-thick and weakly cemented overburden. The temporal and spatial evolution laws of the strata subsidence and influence boundary are closely related to their depth, and their relationships evolve into the Boltzmann function and Boltzmann–parabolic function, respectively. The failure mode of the super-thick and weakly cemented overburden is ‘beam–arch shell–half arch shell’, and the failure boundary exhibits arch fractures.
Hypertrophic cardiomyopathy (HCM) is a heterogeneous myocardial disease often caused by sarcomeric gene mutations. MYH7 is one of the most common genes associated with HCM. In this study, we ...generated a human induced pluripotent stem cell (iPSC) line ZZUNEUi020-A from peripheral blood mononuclear cells of a female HCM patient with the p. R719Q (c. 2156G > A) mutation in MYH7. This cell line expressed pluripotency markers, showed normal female karyotype and could differentiate into all three germ layers in vitro.
•An induced pluripotent stem cell line was generated from a 20-year-old male DCM patient.•The established iPSC line has been confirmed the stable expression of pluripotent markers.•This iPSC line ...provides a control group for studying disease mechanisms, drug screening, and toxicity testing.
Dilated cardiomyopathy (DCM) is the commonest type of cardiomyopathy. In this study, peripheral blood mononuclear cells (PBMCs) were isolated from a DCM patient with the p. Glu12513fs(c.37537delG) mutation in TTN and were reprogrammed to human induced pluripotent stem cells (iPSCs). The ZZUNEUi017-A iPSC line expressed pluripotency markers, exhibiting a normal male karyotype (46, XY) and demonstrating differentiation potential into three germ layers in vitro.
•An iPSC line was from a HCM patient with a heterozygous mutation in ALPK3 gene.•The established iPSC line has been confirmed the stable expression of pluripotent markers.•This iPSC line provides a ...model for studying disease mechanisms and drug screening.
Hypertrophic cardiomyopathy is the commonest monogenic cardiomyopathy in humans and was reported to be associated with ALPK3 gene mutation. We report the generation and characterization of the human induced pluripotent stem cell (iPSC) line ZZUNEUi015-A, which was derived from a patient with a heterozygous mutation in ALPK3 gene (c.1013 T > C) and diagnosed with hypertrophic cardiomyopathy. The ZZUNEUi015-A line maintains the morphology of stem cells, has pluripotency and normal karyotype, and differentiated into three germ layers in vitro.
Landslides caused by underground mining are very common in mountain mining areas, and thus threaten human lives and assets. Under the superposed influence of underground mining and landslides, ...surface movement in mountain areas is different from that in flat areas. Further understanding of the law of surface movement in mountain mining areas can protect the locals and their assets. In this study, an improved survey technique called spherical fitting real-time kinematic was employed to monitor surface movement regularly, and similar material simulation was used as a supplement to reveal the process of strata failure. Results showed that the ground would uplift during underground mining in the valley bottom areas, an action that caused the subsidence velocity curve to appear as a skewed distribution instead of a Gaussian distribution. To improve the prediction accuracy, the prediction model of surface subsidence in mountain mining areas was updated. The mountain surface subsidence prediction system was developed using Visual Basic. Finally, the mechanism of mining landslide was studied. This work is of general interest to the professional public and it will contribute to a more objective knowledge of understanding the surface movement in mountain mining areas.
•The iPSC line was generated from a hypertrophic Cardiomyopathy patient with TNNT2 mutation.•The iPSC line can stably express pluripotent markers and can differentiate into three germ layers.•This ...iPSC line provides a vitro model for studying cardiomyopathy mechanisms, drug screening, and toxicity testing.
A 25-years-old hypertrophic cardiomyopathy male patient donated his peripheral blood mononuclear cells (PBMCs) with heterozygote mutation in theTNNT2 gene. We generated induced pluripotent stem cell (iPSC) with normal karyotypic and expressing NANOG, Lin28, GDF3 and DNMT3. The iPSC line has demonstrated pluripotency by differentiating into three germ layers in vitro. The ZZUNEUi021-A would serve as an in vitro model for loss of TNNT2 function.
The “Three Under Mining” (mining under the buildings, the railways, and the waters) coal resources are stored in the central and eastern China. Many large-scale mine disasters occurred due to ...overburden strata movement and surface subsidence. Longwall mining with superhigh-water material backfilling technology has been improved efficiently to prevent the underground disasters and protect the surface ecological environment. Since underground mine pressure behavior and overlying strata movement are influenced by the backfilling strength and backfilling rates, rational design of backfilling parameters is key to realize the green mining of deep buried coal seams. Based on the combination of geological and production conditions of a deep buried coal seam with composite beam theory, the roof fracture distance was analyzed. The software of UDEC was used to simulate the overlying strata movement laws affected by the different backfilling strength and backfilling rates. With the comparative analysis of the vertical displacement movements and the vertical stress distributions, the reasonable filling rate and water volume fraction were determined to be 90% and 95%, respectively. According to the field experiments, the underground dynamic load was low enough for the safe mining, and the village building can be kept in a stable state with the application of the backfilling technology. The research results in a scientific basis for the coordinated development between the safe and efficient mining of deep buried coal resources and protection of the surface ecological environment.
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