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1.
Environ Sci Pollut Res Int ; 31(9): 14270-14283, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38277103

RESUMEN

Cropland is the foundation of food security. Coal is the guarantee of energy security. As China's demand for coal and grain continues to increase, so does the overlap area of their production bases. Unrestrained underground mining can cause serious damage to cropland, leading to increasing conflicts between coal mining and food production. Thus, this paper used a partial backfilling mining technology to control surface subsidence and thus protect cropland. The key to successfully implementing the technology is how to design the panel size. However, the design efficiency of the conventional enumeration method is low. Therefore, this paper proposed a design approach based on improved particle swarm optimization. The results indicated that the approach could quickly find the optimal size of the panel compared with the enumeration method and particle swarm optimization. Moreover, if the longwall panel is mined according to the size designed by the approach, the cropland will be protected, and the cost will be reduced. This study can provide technical support for the cooperative development of cropland protection and coal mining in a coal-cropland overlapping area.


Asunto(s)
Minas de Carbón , Minas de Carbón/métodos , Carbón Mineral , Productos Agrícolas , China
2.
Sci Rep ; 14(1): 332, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172330

RESUMEN

Underground coal mining leads to land subsidence, which, in turn, results in damage to buildings and infrastructure, disturbs the original ecological environment, and hinders the sustainable development of coal mining cities. A reasonable estimation of land subsidence, on the other hand, is the foundation for building protection, land reclamation, and ecological environment reconstruction. However, when we applied the existing land subsidence estimation theory to the deep mining areas of the Ordos coalfield in western China, there was a significant deviation between the estimations and the measurements. To explain such unusual case, we propose using the overburden's average GSI (Geological Strength Index) value instead of the compressive strength (UCS) of rock specimens for a better representation of the overburden's overall properties. By using on-site subsidence monitoring results and historical data, we provided evidence which supports that the overburden's average GSI value has a much greater impact on subsidence rates than the UCS. Subsequently, we investigated the relationship between three typical overburden's GSI values and the subsidence rates via a calibrated numerical model, revealing the variation patterns of maximum surface subsidence when the overburden's average GSI value is set at 30, 50, and 75, respectively. Finally, on the basis of the measured and simulated results, we discussed a non-conventional strip mining method for mining subsidence control in the deep mining areas of the Ordos coalfield in western China, and explained why it is possible and what are the significant advantages behind. The proposed methods, findings, and suggestions in this paper are therefore quite helpful for researchers and engineers who wish to estimate and control the mining-induced land subsidence, as well as for those who are particularly interested in the study of environment science related to land subsidence.

3.
Environ Sci Pollut Res Int ; 31(6): 9685-9699, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38191739

RESUMEN

The planned viaduct in Jining, Shandong is a priority project in the city. However, the 63 working faces of a mine in Jining is only 3 m away from the planned viaduct, posing a serious threat to the safety of the viaduct's construction. Consequently, it is essential to evaluate the stability of the planned viaduct's goaf area under the influence of the 63 working faces. However, the 63 working faces are short faces, and there is a lack of corresponding prediction of surface residual subsidence. To address this issue, this paper employs theoretical analysis and numerical simulation to uncover the foundation deformation mechanism and characteristics of fractured rock and soil mass in the short goaf. Subsequently, a residual subsidence prediction method for the short goaf was proposed for the viaduct mined-out area. This new approach was implemented for the planned viaduct in Jining, and its effectiveness was validated through InSAR and leveling monitoring results. The research findings offer technical support for viaduct construction in areas affected by underground mining.


Asunto(s)
Minería , Suelo , Simulación por Computador , Ciudades
4.
Cell Calcium ; 117: 102822, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38101154

RESUMEN

Hypertrophic cardiomyopathy (HCM), the most common inherited heart disease, is frequently caused by mutations in the ß-cardiac myosin heavy chain gene (MYH7). Abnormal calcium handling and diastolic dysfunction are archetypical features of HCM caused by MYH7 gene mutations. However, the mechanism of how MYH7 mutations leads to these features remains unclear, which inhibits the development of effective therapies. Initially, cardiomyocytes were generated from induced pluripotent stem cells from an eight-year-old girl diagnosed with HCM carrying a MYH7(C.1063 G>A) heterozygous mutation(mutant-iPSC-CMs) and mutation-corrected isogenic iPSCs(control-iPSC-CMs) in the present study. Next, we compared phenotype of mutant-iPSC-CMs to that of control-iPSC-CMs, by assessing their morphology, hypertrophy-related genes expression, calcium handling, diastolic function and myofilament calcium sensitivity at days 15 and 40 respectively. Finally, to better understand increased myofilament Ca2+ sensitivity as a central mechanism of central pathogenicity in HCM, inhibition of calcium sensitivity with mavacamten can improveed cardiomyocyte hypertrophy. Mutant-iPSC-CMs exhibited enlarged areas, increased sarcomere disarray, enhanced expression of hypertrophy-related genes proteins, abnormal calcium handling, diastolic dysfunction and increased myofilament calcium sensitivity at day 40, but only significant increase in calcium sensitivity and mild diastolic dysfunction at day 15. Increased calcium sensitivity by levosimendan aggravates cardiomyocyte hypertrophy phenotypes such as expression of hypertrophy-related genes, abnormal calcium handling and diastolic dysfunction, while inhibition of calcium sensitivity significantly improves cardiomyocyte hypertrophy phenotypes in mutant-iPSC-CMs, suggesting increased myofilament calcium sensitivity is the primary mechanisms for MYH7 mutations pathogenesis. Our studies have uncovered a pathogenic mechanism of HCM caused by MYH7 gene mutations through which enhanced myofilament calcium sensitivity aggravates abnormal calcium handling and diastolic dysfunction. Correction of the myofilament calcium sensitivity was found to be an effective method for treating the development of HCM phenotype in vitro.


Asunto(s)
Cardiomiopatías , Cardiomiopatía Hipertrófica , Células Madre Pluripotentes Inducidas , Niño , Femenino , Humanos , Calcio/metabolismo , Miosinas Cardíacas/genética , Miosinas Cardíacas/metabolismo , Cardiomiopatías/metabolismo , Cardiomiopatía Hipertrófica/genética , Cardiomiopatía Hipertrófica/patología , Hipertrofia/metabolismo , Hipertrofia/patología , Células Madre Pluripotentes Inducidas/metabolismo , Mutación/genética , Miocitos Cardíacos/metabolismo , Miofibrillas/metabolismo , Miofibrillas/patología , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo
5.
Environ Sci Pollut Res Int ; 30(18): 52049-52061, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36826765

RESUMEN

In response to the problem that the actual extent of coal mining impacts on the surface in thick loose layer mines significantly exceeds the theoretical predictions, based on the literature study, the form of influence of thick loose layer on the predicted parameters of the probability integral method is summarized and analyzed; taking into account the influence of the subsidence coefficient, the sine modification formula of the major influence radius and the logistic modification formula of the subsidence coefficient are established, respectively, and based on the characteristics of the major influence radius, a new subsidence basin demarcation point is proposed and a novel probability integral method segmental parameter modified prediction model is constructed. The simulated experiment and real data experiment results prove that the constructed probability integral method segmented parameter modified model can both reduce the convergence of surface subsidence basin edge better and take into account the predicted accuracy inside the subsidence basin. The research achievements provide scientific data support for disaster warning, pollution management, ecological restoration, and coordination between coal mining and surface city construction in thick loose layer mining areas.


Asunto(s)
Minas de Carbón , Desastres , Minas de Carbón/métodos , China
6.
Artículo en Inglés | MEDLINE | ID: mdl-36429619

RESUMEN

Disasters such as rock bursts and mine earthquakes became increasingly serious with the increase in mining depth in Erdos Coal Field and became serious problems that restrict high-strength continuous mining of coal mines. In this study, strata movement and energy polling distribution of ultrathick weak-bonding sandstone layers were controlled by the local filling−caving multi-faces coordinated mining technique, which was based on the analysis of subsidence and overlying structural characteristics in the Yingpanhao mining area. Moreover, the influencing factors and the control effect laws were investigated. Surface subsidence and energy polling distribution control effects of different mining modes were compared, which confirmed the superiority of local filling based on the main key stratum. According to the results, the maximum surface subsidence velocity of the first mining face was 1.24 mm/d, which indicates the presence of a logistic functional relationship between the mining degree and subsidence factors. When the mining degree was close to full mining, the practical surface subsidence was smaller than the corresponding logistic functional value. The largest influencing factor for the strata movement control effect of partial filling mining based on the main key stratum was the width of the caving face, followed by the filling ratio, section pillar width, and width of the filling face, successively. With respect to the influencing degree on the energy polling distribution of partial filling mining based on the main key stratum, the order followed as section pillar width > filling ratio > caving working face > width of backfilling working face. Additionally, the comparative analysis from the perspectives of control effect, resource utilization, and cost-effectiveness demonstrated that partial filling mining based on the main key stratum was one of the techniques with high cost-effectiveness in controlling strata movement and relieving rock bursts, mining earthquakes, and subsidence disasters.

7.
Environ Sci Pollut Res Int ; 29(45): 69022-69036, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35554833

RESUMEN

Backfilling mining is a green mining method. The rational design of the compressed ratio of the backfilling body can reduce backfilling mining costs while avoiding mining-induced environmental damage. At present, the enumeration method is a common design method for the compressed ratio of the backfilling body of backfilling mining under buildings (structures). However, the design method has some problems, such as cumbersome processes and time consumption. Therefore, this paper proposes an intelligent optimization design method of the compressed ratio of backfilling body and constructs the design flow of the method. The method takes economic benefits as the optimization goal and takes the mining-induced subsidence of protected objects to meet their fortification requirements as the constraint condition. Within the feasible region of the compressed ratio, the intelligent optimization algorithm is used to search for the minimum compressed ratio that satisfies the constraints. This paper used the method to design the compressed ratio of the backfilling panel in the Dongtan Coal Mine. The research results show that the method can quickly design the optimal compressed ratio compared with the enumeration method and cut the production cost on the premise of the safety of ground buildings (structures).


Asunto(s)
Minas de Carbón , Carbón Mineral , Minas de Carbón/métodos , Presión
8.
Front Cardiovasc Med ; 9: 864366, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35514438

RESUMEN

Background: Heart failure with improved left ventricular ejection fraction (HFiEF) is linked to a good clinical outcome. The purpose of this study was to create an easy-to-use model to predict the occurrence of HFiEF in patients with heart failure (HF), 1 year after successful percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) (CTO PCI). Methods: Patients diagnosed with HF who successfully underwent CTO PCI between January 2016 and August 2019 were included. To mitigate the effect of residual stenosis on left ventricular (LV) function, we excluded patients with severe residual stenosis, as quantitatively measured by a residual synergy between PCI with Taxus and Cardiac Surgery score (rSS) of >8. We gathered demographic data, medical history, angiographic and procedural characteristics, echocardiographic parameters, laboratory results, and medication information. The least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression models were used to identify predictors of HFiEF 1 year after CTO revascularization. A nomogram was established and validated according to the area under the receiver operating characteristic curve (AUC) and calibration curves. Internal validation was performed using bootstrap resampling. Results: A total of 465 patients were finally included in this study, and 165 (35.5%) patients experienced HFiEF 1 year after successful CTO PCI. According to the LASSO regression and multivariate logistic regression analyses, four variables were selected for the final prediction model: age [odds ratio (OR): 0.969; 95% confidence interval (CI): 0.952-0.988; p = 0.001], previous myocardial infarction (OR: 0.533; 95% CI: 0.357-0.796; p = 0.002), left ventricular end-diastolic dimension (OR: 0.940; 95% CI: 0.910-0.972; p < 0.001), and sodium glucose cotransporter two inhibitors (OR: 5.634; 95% CI: 1.756-18.080; p = 0.004). A nomogram was constructed to present the results. The C-index of the model was 0.666 (95% CI, 0.613-0.719) and 0.656 after validation. The calibration curve demonstrated that the nomogram agreed with the actual observations. Conclusions: We developed an simple and effective nomogram for predicting the occurrence of HFiEF in patients with HF, 1 year after successful CTO PCI without severe residual stenosis.

9.
Stem Cell Res ; 58: 102622, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34929444

RESUMEN

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.


Asunto(s)
Cardiomiopatía Hipertrófica , Células Madre Pluripotentes Inducidas , Adulto , Cardiomiopatía Hipertrófica/genética , Diferenciación Celular , Genes Homeobox , Humanos , Leucocitos Mononucleares , Masculino , Mutación/genética , Troponina T/genética
10.
Stem Cell Res ; 53: 102262, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33636496

RESUMEN

HCM is one of the most common inheritable cardiac disease. In our study, we established a human-induced pluripotent stem cells (hiPSCs) line (ZZUNEUi016-A) from a hypertrophic cardiomyopathy patient with the pathogenic heterozygote mutation in MYH7 gene. ZZUNEUi016-A expressed pluripotency markers with normal karyotype and showed the ability to differentiate into all three germ layers in vitro.


Asunto(s)
Cardiomiopatía Hipertrófica , Células Madre Pluripotentes Inducidas , Miosinas Cardíacas/genética , Cardiomiopatía Hipertrófica/genética , Estratos Germinativos , Heterocigoto , Humanos , Mutación , Cadenas Pesadas de Miosina/genética
11.
Stem Cell Res ; 52: 102247, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33607470

RESUMEN

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.


Asunto(s)
Cardiomiopatías , Cardiomiopatía Hipertrófica , Células Madre Pluripotentes Inducidas , Cardiomiopatía Hipertrófica/genética , Heterocigoto , Humanos , Mutación
12.
Stem Cell Res ; 52: 102248, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33610015

RESUMEN

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.


Asunto(s)
Cardiomiopatía Dilatada , Células Madre Pluripotentes Inducidas , Cardiomiopatía Dilatada/genética , Diferenciación Celular , Conectina , Humanos , Leucocitos Mononucleares , Masculino , Mutación
13.
Stem Cell Res ; 51: 102158, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33453578

RESUMEN

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.


Asunto(s)
Cardiomiopatía Hipertrófica , Células Madre Pluripotentes Inducidas , Miosinas Cardíacas/genética , Cardiomiopatía Hipertrófica/genética , Femenino , Humanos , Leucocitos Mononucleares , Mutación , Cadenas Pesadas de Miosina/genética
14.
BMC Public Health ; 20(1): 1663, 2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33153479

RESUMEN

BACKGROUND: Ambient air pollution is becoming a serious environmental problem in China. The results were inconsistent on that air pollution was a risk factor of preeclampsia in pregnancy. METHODS: Total 116,042 pregnant women were enrolled from 22 hospitals in 10 cities of Hebei Province, China from January 1, 2015 to December 31, 2017. The parturients were divided into preeclampsia group (PE group) and non-preeclampsia group (non-PE group). The data of air pollutants, namely, particulate matter (PM)2.5, PM10, NO2, SO2, CO, O3 were collected from China Environmental Inspection Station. RESULTS: Among the 116,042 pregnant women, 2988 (2.57%) pregnant women were diagnosed with preeclampsia. The concentrations of exposed PM2.5, PM10, NO2 and O3 in the PE group were significantly higher than those in the non-PE group, and they were risk factors of the PE group in the first and second trimester of pregnancy respectively. The concentrations of exposed SO2 and CO in PE patients and non-PE women were not different, but high concentration of these air pollutants were risk factors to PE in the second trimester. CONCLUSION: The exposure to PM2.5, PM10, NO2, O3 were risk factors for preeclampsia in the first and second trimester of pregnancy, while only at high level, SO2 and CO were risk factors for preeclampsia in the second trimester of pregnancy.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Preeclampsia , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , China/epidemiología , Ciudades , Femenino , Humanos , Material Particulado/efectos adversos , Material Particulado/análisis , Preeclampsia/epidemiología , Preeclampsia/etiología , Embarazo , Estudios Retrospectivos
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