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1.
Inorg Chem ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973778

RESUMO

Pentazole (cyclo-HN5) is a unique heterocycle categorized as both an organic and inorganic compound. However, attempts to synthesize and characterize cyclo-HN5 have been unsuccessful thus far. In this study, we synthesized a cyclo-HN5 solution and investigated the spectra, structure, aromaticity, acidity, and stability of cyclo-HN5. The lone pair of electrons on the protonated N atom of cyclo-HN5 participates in π-electron delocalization, forming two N═N bonds. Further investigations suggest that cyclo-HN5 exhibits significantly decreased π aromaticity and slightly lower σ aromaticity than cyclo-N5-. Experimental results suggest that pure cyclo-HN5 is unstable at ambient temperatures and pressures, but it can be isolated at high pressures or stabilized in solution by abundant hydrogen bonds. The pKa of cyclo-HN5 was determined as 1.63 (H2O, 25 °C) via potentiometric titration, indicating that cyclo-HN5 is a medium-strong acid. This study reveals the fundamental structure and properties of cyclo-HN5, thereby providing important data for advancing cyclo-HN5 chemistry.

2.
Chemphyschem ; 25(12): e202400105, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38721760

RESUMO

Pentazole is regarded as a unique inorganic molecule that possess organic heterocyclic structure. Therefore, the research on pentazolyl derivatives represents a cutting-edge direction in both contemporary inorganic chemistry and heterocyclic chemistry. Moreover, their synthesis is regarded as the most significant research topic in the field of energetic materials due to the great potential of pentazolyl derivatives to breakthrough the energy bottleneck of CHNO-based energetic materials. However, synthesizing pentazolyl derivatives is challenging. To provide a theoretical support for the synthesis, we conducted theoretical studies on six single-ring pentazolyl derivatives with different functional groups. The results suggest that derivatization reduces the bond strength and weakens the aromaticity of the pentazolate ring. Further analysis showed that derivatization mainly affects the π aromaticity of the pentazolate ring, and ultimately causing poor stability of the pentazolyl derivatives. Among the six derivatives investigated in this study, fluoro pentazole (cyclo-N5-F) and hydroxyl pentazole (cyclo-N5-OH) possess good aromaticity, which is similar to the reported cyclo-N5-NCHN(CH3)2. Further calculations show that the kinetic stability of cyclo-N5-OH is higher than that of cyclo-N5-F. These results collectively indicate that cyclo-N5-OH is a promising candidate for synthesizing single-ring pentazolyl derivatives.

3.
J Affect Disord ; 356: 105-114, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38580036

RESUMO

BACKGROUND: Seeking objective quantitative indicators is important for accurately recognizing major depressive disorder (MDD). Lempel-Ziv complexity (LZC), employed to characterize neurological disorders, faces limitations in tracking dynamic changes in EEG signals due to defects in the coarse-graining process, hindering its precision for MDD objective quantitative indicators. METHODS: This work proposed Adaptive Permutation Lempel-Ziv Complexity (APLZC) and Adaptive Weighted Permutation Lempel-Ziv Complexity (AWPLZC) algorithms by refining the coarse-graining process and introducing weight factors to effectively improve the precision of LZC in characterizing EEGs and further distinguish MDD patients better. APLZC incorporated the ordinal pattern, while False Nearest Neighbor and Mutual Information algorithms were introduced to determine and adjust key parameters adaptively. Furthermore, we proposed AWPLZC by assigning different weights to each pattern based on APLZC. Thirty MDD patients and 30 healthy controls (HCs) were recruited and their 64-channel resting EEG signals were collected. The complexities of gamma oscillations were then separately computed using LZC, APLZC, and AWPLZC algorithms. Subsequently, a multi-channel adaptive K-nearest neighbor model was constructed for identifying MDD patients and HCs. RESULTS: LZC, APLZC, and AWPLZC algorithms achieved accuracy rates of 78.29 %, 90.32 %, and 95.13 %, respectively. Sensitivities reached 67.96 %, 85.04 %, and 98.86 %, while specificities were 88.62 %, 95.35 %, and 89.92 %, respectively. Notably, AWPLZC achieved the best performance in accuracy and sensitivity, with a specificity limitation. LIMITATION: The sample size is relatively small. CONCLUSION: APLZC and AWPLZC algorithms, particularly AWPLZC, demonstrate superior effectiveness in differentiating MDD patients from HCs compared with LZC. These findings hold significant clinical implications for MDD diagnosis.


Assuntos
Algoritmos , Transtorno Depressivo Maior , Eletroencefalografia , Humanos , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/diagnóstico , Adulto , Feminino , Masculino , Processamento de Sinais Assistido por Computador , Pessoa de Meia-Idade , Estudos de Casos e Controles , Sensibilidade e Especificidade
4.
Animals (Basel) ; 14(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38396529

RESUMO

Cadmium (Cd) pollution has become a global issue due to industrial and agricultural developments. However, the molecular mechanism of Cd-induced detrimental effects and relevant signal transduction/metabolic networks are largely unknown in marine fishes. Here, greenfin horse-faced filefish (Thamnaconus septentrionalis) were exposed to 5.0 mg/L Cd up to 7 days. We applied both biochemical methods and multi-omics techniques to investigate how the gills respond to Cd exposure. Our findings revealed that Cd exposure caused the formation of reactive oxygen species (ROS), which in turn activated the MAPK and apoptotic pathways to alleviate oxidative stress and cell damage. Glycolysis, protein degradation, as well as fatty acid metabolism might assist to meet the requirements of nutrition and energy under Cd stress. We also found that long-term (7 days, "long-term" means compared to 12 and 48 h) Cd exposure caused the accumulation of succinate, which would in turn trigger an inflammatory response and start an immunological process. Moreover, ferroptosis might induce inflammation. Overall, Cd exposure caused oxidative stress, energy metabolism disturbance, and immune response in greenfin horse-faced filefish. Our conclusions can be used as references for safety risk assessment of Cd to marine economic fishes.

5.
Angew Chem Int Ed Engl ; 63(11): e202317355, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38165698

RESUMO

As the fourth full-nitrogen structure, the pentazolate anion (cyclo-N5 - ) was highly coveted for decades. In 2017, the first air-stable non-metal pentazolate salt, (N5 )6 (H3 O)3 (NH4 )4 Cl, was obtained, representing a milestone in this field. As the latest member of the azole family, cyclo-N5 - is comprised of five nitrogen atoms. Although significant attention has been paid to the potential of cyclo-N5 - as an energetic material, its poor thermostability hinders any practical application. However, the unique ring structure and multiple coordination capability of cyclo-N5 - provide a platform for the fabrication of various structures, among which pentasil-zeolite topologies are the most intriguing. In addition, the introduction of structure-directing auxiliaries enables the self-assembly of diverse topological architectures, potentially imparting cyclo-N5 - with the potential to impact wide-ranging areas of coordination chemistry and topology. In this minireview, different pentasil-zeolite topologies based on metal-pentazolate frameworks are evaluated. To date, three zeolitic and zeolite-like topologies have been reported, namely the melanophlogite (MEP), chibaite (MTN), and unj topologies. The MEP topology consists of two nanocages, Na20 N60 and Na24 N60 , whereas the MTN topology contains Na20 N60 and Na28 N80 nanocages. Furthermore, the unj topology features multiple homochiral channels consisting of two helical chains. Various possible strategies for obtaining additional pentasil-zeolite topologies are also discussed.

6.
Exp Ther Med ; 27(2): 89, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38274342

RESUMO

Ferroptosis-related genes may play a critical regulatory role in the pathogenesis of Crohn's disease (CD). The purpose of the present study was to identify genes expressed in CD that are associated with ferroptosis, and to provide guidance in the diagnosis and therapy of CD. CD mRNA expression data were initially gathered from the Gene Expression Omnibus (GEO) database. GSE75214 and GSE102133 datasets were selected as the major targets and were analyzed for differentially expressed genes (DEGs). Subsequently, R software was used to analyze the common genes among the DEGs between CD and ferroptosis-related genes. Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genome pathway analysis were conducted to identify related pathways and functions. Protein-protein interaction (PPI) analysis was performed to identify target genes. The DSigDB website was used to predict potential target drugs for hub genes. Reverse transcription-quantitative (RT-q) PCR was employed to detect the expression of these ferroptosis-related genes in clinical samples obtained from healthy controls and patients with CD. According to the two GEO datasets, 13 ferroptosis DEGs (11 upregulated genes and two downregulated genes) were identified in CD with thresholds of P<0.05 and |log2 fold change|>1, and were selected for further analysis. PPI analysis indicated the mutual effects among these genes and filtered out five hub genes. The top 10 potential targeted drugs were selected. The qPCR results showed that the expression levels of three genes, namely, IL-6, prostaglandin-endoperoxide synthase 2 (PTGS2) and dual oxidase 2 (DUOX2), were different between CD samples and healthy samples. This result was consistent with the results obtained from the bioinformatics analysis. In conclusion, bioinformatics analysis identified a total of 13 ferroptosis-associated genes in CD. Further verification by qPCR showed that IL-6, PTGS2 and DUOX2 may affect the process of CD by regulating ferroptosis. These findings might provide new biomarkers, diagnostic and therapeutic markers for CD.

7.
ACS Omega ; 8(48): 45854-45866, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38075766

RESUMO

In this paper, a full solid waste-based grouting material was prepared using three industrial solid wastes, i.e., sludge, coal gangue (CG), and ground granulated blast furnace slag (GGBS), based on the concepts of synergy and complementarity. The effects of the dosage of raw sewage sludge (SS), incineration-activated sewage sludge ash (SSA), and an alkali activator on the fluidity, water separation rate, and mechanical strength of solid waste-based grouting materials were systematically investigated. The mechanism of action was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Finally, the leaching characteristics and stabilization efficiency of heavy metals in solid-sample-based slurry stones were determined. The experimental results show that the slurry fluidity and water separation proportion are negatively correlated with the amount of sludge. The rate of decline first increases and then decreases. When the SSA content is greater than 10%, the precipitation rate can be controlled to within 5%. The optimal amount of alkaline activator is 8%, and its effect on the mechanical strength is more significant than that of sludge. With an increase in the SSA dosage, the compressive strength first increases and then decreases. At 25%, the strength still reaches 20.8 MPa, and the decrease from 0 to 25% is only 26.2%. On the contrary, the addition of SS continues to decrease the strength of the stone body by 81.9%. The high organic content and low volcanic ash activity in SS hinder the development of hydration cementation. In addition, the comparative analysis demonstrated the contribution of the volcanic ash activity possessed by SSA to the mechanical strength supplement after incineration. The incineration treatment caused the calcite (CaCO3) in SS to decompose at high temperatures, and more Ca sources were introduced in SSA. The incorporation of SSA in the cementation system resulted in higher Ca/Si and Ca/Al ratios, promoting the formation of C-(A)-S-H gel. Moreover, this incorporation enhances the stability of heavy metals within the slurry, reducing the potential environmental risk associated with the leaching of Cr and Ni from the raw materials. Consequently, these findings comply with the leaching requirements specified by the environmental standards. The research provides innovative insights into the synergistic resource utilization of SS and SSA with coal-based solid waste to prepare environmentally friendly, high-performance, and cost-effective grouting materials.

8.
J Fungi (Basel) ; 9(10)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37888234

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are persistent environmental pollutants that pose a threat to human health. Among these PAHs, benzo[a]pyrene (BaP), a five-ring compound, exhibits high resistance to biodegradation. White-rot fungus Phlebia acerina S-LWZ20190614-6 has demonstrated higher BaP degradation capabilities compared with Phanerochaete chrysosporium and P. sordida YK-624, achieving a degradation rate of 57.7% after 32 days of incubation under a ligninolytic condition. To further enhance the biodegradation rate, three nonionic surfactants were used, and the addition of 1 or 2 g·L-1 of polyethylene glycol monododecyl ether (Brij 30) resulted in nearly complete BaP biodegradation by P. acerina S-LWZ20190614-6. Interestingly, Brij 30 did not significantly affect the activity of manganese peroxidase and lignin peroxidase, but it did decrease laccase activity. Furthermore, the impact of cytochrome P450 on BaP degradation by P. acerina S-LWZ20190614-6 was found to be relatively mild. Transcriptomic analysis provided insights into the degradation mechanism of BaP, revealing the involvement of genes related to energy production and the synthesis of active enzymes crucial for BaP degradation. The addition of Brij 30 significantly upregulated various transferase and binding protein genes in P. acerina S-LWZ20190614-6. Hence, the bioremediation potential of BaP by the white-rot fungus P. acerina S-LWZ20190614-6 holds promise and warrants further exploration.

9.
iScience ; 26(10): 108054, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37822502

RESUMO

Peroxymonosulfate (PMS)-based advanced oxidation processes in liquid phase systems can actively degrade toluene. In this work, the catechol structural surfactant was introduced to synthesize the dispersed and homogeneous CoFe2O4 nanospheres and embedded into MoS2 nanoflowers to form magnetically separable heterojunction catalysts. The innovative approach effectively mitigated the traditionally low reduction efficiency of transition metal ions during the heterogeneous activation process. In CoFe2O4/MoS2/PMS system, the toluene removal efficiency remained 95% within 2 h. The contribution of SO4⋅-, ·O2-, ·OH, and 1O2 was revealed by radical quenching experiment and electron paramagnetic resonance spectroscopy. The results illustrated that MoS2 offers ample reduction sites for facilitating PMS activation via Fe3+/Fe2+ redox interactions. Furthermore, an investigation into the toluene degradation pathway within the CoFe2O4/MoS2/PMS system revealed its capability to suppress the formation of toxic byproducts. This ambient-temperature liquid-phase method presented promising route for the removal of industrial volatile organic pollutants.

10.
Inorg Chem ; 62(42): 17199-17206, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37823764

RESUMO

Energetic materials have been widely applied in civil and military fields, whose thermostability is a key indicator to evaluate their safety levels under severe conditions. Herein, two novel energetic metal-organic frameworks (EMOFs), namely, 4 and 6, were experimentally obtained and comprehensively characterized. The two EMOFs both possess unique three-dimensional (3D) coordination structures. With a high crystal density of 2.184 g·cm-3, EMOF 4 exhibits outstandingly superior thermostability (onset: 290 °C; peak: 303 °C), while EMOF 6 features onset and peak decomposition temperatures of 220 and 230 °C. The calculated energetic parameters of 4 and 6 are as follows: detonation velocity: 8731 m·s-1 and 8294 m·s-1; detonation pressure: 26.5 and 26.4 GPa. Compared to EMOF 6, EMOF 4 features high energy, excellent thermostability, and low mechanical sensitivities, which should be partly attributed to more plentiful coordination interactions. More coordination bonds are conducive to strengthening the EMOF framework, which needs much more energy to collapse, thereby maintaining higher thermal stability. The above favorable characteristics not only indicate EMOF 4 has a promising future in applications as a thermostable explosive but also provide an effective and feasible strategy for developing novel heat-resistant energetic materials via reinforced frame structures of EMOFs.

11.
Cereb Cortex ; 33(15): 9313-9324, 2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37310187

RESUMO

Auditory steady-state response underlying gamma oscillations (gamma-ASSR) have been explored in patients with major depressive disorder (MDD), while ignoring the spatiotemporal dynamic characteristics. This study aims to construct dynamic directed brain networks to explore the disruption of spatiotemporal dynamics underlying gamma-ASSR in MDD. This study recruited 29 MDD patients and 30 healthy controls for a 40 Hz auditory steady-state evoked experiment. The propagation of gamma-ASSR was divided into early, middle, and late time interval. Partial directed coherence was applied to construct dynamic directed brain networks based on graph theory. The results showed that MDD patients had lower global efficiency and out-strength in temporal, parietal, and occipital regions over three time intervals. Additionally, distinct disrupted connectivity patterns occurred in different time intervals with abnormalities in the early and middle gamma-ASSR in left parietal regions cascading forward to produce dysfunction of frontal brain regions necessary to support gamma oscillations. Furthermore, the early and middle local efficiency of frontal regions were negatively correlated with symptom severity. These findings highlight patterns of hypofunction in the generation and maintenance of gamma-band oscillations across parietal-to-frontal regions in MDD patients, which provides novel insights into the neuropathological mechanism underlying gamma oscillations associated with aberrant brain network dynamics of MDD.


Assuntos
Transtorno Depressivo Maior , Humanos , Encéfalo , Mapeamento Encefálico , Lobo Parietal , Comunicação , Imageamento por Ressonância Magnética/métodos
12.
Front Neurosci ; 17: 1092539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36777641

RESUMO

For decades, neuromodulation technology has demonstrated tremendous potential in the treatment of neuropsychiatric disorders. However, challenges such as being less intrusive, more concentrated, using less energy, and better public acceptance, must be considered. Several novel and optimized methods are thus urgently desiderated to overcome these barriers. In specific, temporally interfering (TI) electrical stimulation was pioneered in 2017, which used a low-frequency envelope waveform, generated by the superposition of two high-frequency sinusoidal currents of slightly different frequency, to stimulate specific targets inside the brain. TI electrical stimulation holds the advantages of both spatial targeting and non-invasive character. The ability to activate deep pathogenic targets without surgery is intriguing, and it is expected to be employed to treat some neurological or psychiatric disorders. Recently, efforts have been undertaken to investigate the stimulation qualities and translation application of TI electrical stimulation via computational modeling and animal experiments. This review detailed the most recent scientific developments in the field of TI electrical stimulation, with the goal of serving as a reference for future research.

13.
Clin Neurophysiol ; 146: 65-76, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36535093

RESUMO

OBJECTIVE: Neural oscillations during sensory and cognitive events interact at different frequencies. However, such evidence in major depressive disorder (MDD) remains scarce. We explored the possible abnormal neural oscillations in MDD by analyzing theta-phase/gamma-amplitude coupling (TGC). METHODS: Resting-state and auditory steady-state response (ASSR) electroencephalography recordings were obtained from 35 first-episode MDD and 35 healthy controls (HCs). TGC during rest, ASSR stimulation, and ASSR baseline between and within groups were analyzed to evaluate MDD alterations. Receiver operating characteristic (ROC), TGC comparison between MDD severity subgroups (mild, moderate, major), and correlations were investigated to determine the potential use of altered TGC for identifying MDD. RESULTS: In MDD, left fronto-central TGC decreased during stimulation, while right fronto-central TGC increased during baseline. The area under ROC curve for altered TGC was 0.863. Furthermore, during stimulation, moderate and major MDD groups exhibited significantly lower TGC than mild group, and fronto-central TGC was negatively correlated with depression scale scores. CONCLUSIONS: Our results provided the first evidence for an abnormal TGC response of fronto-central regions in MDD during an ASSR task. Importantly, altered TGC may be promising biomarkers of MDD. SIGNIFICANCE: Our findings enhance the understanding of physiological mechanisms underlying MDD and aid in its clinical diagnosis.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/diagnóstico , Eletroencefalografia , Ritmo Gama/fisiologia , Curva ROC
14.
J Affect Disord ; 323: 299-308, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36462607

RESUMO

BACKGROUND: Increasing depression patients puts great pressure on clinical diagnosis. Audio-based diagnosis is a helpful auxiliary tool for early mass screening. However, current methods consider only speech perception features, ignoring patients' vocal tract changes, which may partly result in the poor recognition. METHODS: This work proposes a novel machine speech chain model for depression recognition (MSCDR) that can capture text-independent depressive speech representation from the speaker's mouth to the listener's ear to improve recognition performance. In the proposed MSCDR, linear predictive coding (LPC) and Mel-frequency cepstral coefficients (MFCC) features are extracted to describe the processes of speech generation and of speech perception, respectively. Then, a one-dimensional convolutional neural network and a long short-term memory network sequentially capture intra- and inter-segment dynamic depressive features for classification. RESULTS: We tested the MSCDR on two public datasets with different languages and paradigms, namely, the Distress Analysis Interview Corpus-Wizard of Oz and the Multi-modal Open Dataset for Mental-disorder Analysis. The accuracy of the MSCDR on the two datasets was 0.77 and 0.86, and the average F1 score was 0.75 and 0.86, which were better than the other existing methods. This improvement reveals the complementarity of speech production and perception features in carrying depressive information. LIMITATIONS: The sample size was relatively small, which may limit the application in clinical translation to some extent. CONCLUSION: This experiment proves the good generalization ability and superiority of the proposed MSCDR and suggests that the vocal tract changes in patients with depression deserve attention for audio-based depression diagnosis.


Assuntos
Percepção da Fala , Fala , Humanos , Depressão/diagnóstico , Reconhecimento Psicológico , Redes Neurais de Computação
15.
Sci Rep ; 12(1): 17049, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36220976

RESUMO

We have investigated the activation characteristics of mining faults and the effect of grouting reinforcement under thick loose layer and thin bedrock of the working face and evaluate their impact on the safety of mining at similar working faces. Implementing the geological conditions of the 331 working face of the Yangcun Coal Mine (China) of the Yankuang Energy Group Corporation, we have analyzed mechanically the process of fault activation at first. Subsequently, we have obtained the mechanical criterion of fault slip and the expression of relative strength of the nearby rock mass. Using numerical software we have simulated and analyzed the damage characteristics of different bedrock thicknesses on overlying rocks and faults in the fluid-solid coupling mode. In addition, we have studied the controlling effect of grouting reinforcement on fault activation, which has been verified in the field. The main results of our study show that: 1. The mechanical properties of the rock mass near the fault interface have changed and they are related to the cohesive force of the interface; 2. The water inrush mode of the working face changes under different bedrock thickness, and the thinner the bedrock, the less easily the fault is destroyed 3. The slip of the high-level fault is reduced after the grouting of the fault, the propagation of the fracture zone at the fault is suppressed, the seepage of the aquifer water is prevented, and the safe recovery is realized. The results of our study provide a scientific basis for the secure mining across the fault of the 331 working face of Yangcun Coal Mine. Based on the results of our study the working face can be mined safely from now on and in the future.

16.
ACS Omega ; 7(16): 13604-13614, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35559151

RESUMO

Mining-induced fractures often constitute water inrush channels, which lead to mine water inrush accidents. In this paper, a coupled model of stress-seepage-damage based on micromechanics is established, which simulates the initiation and propagation of cracks in rock materials and their interaction with fluid flow. The method combines the continuous damage model with the effective stress principle, in which the elastic modulus and permeability are related to the damage variables. The model is implemented via the COMSOL code based on the finite element method, and the reliability of the model is verified by the axial compression-seepage test of standard rock samples. According to the actual geological conditions of F13 fault in Wugou Coal Mine, Anhui Province, the damage of the floor rock mass and the risk of fault water inrush in the 1033 mining face with 50, 40, 30, and 20 m waterproof coal pillars are predicted. When the coal pillar width is 30 or 20 m, the fault, the surrounding rock of the fault, and the failure zone of the floor constitute the water inrush channel. This model provides an intuitive understanding of the rock damage and water inrush evolution, which is difficult to observe, and will contribute to prevent water inrush disasters in practical engineering.

17.
ACS Omega ; 7(11): 9430-9442, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35350366

RESUMO

To study and prevent bed separation water inrush accidents in coal mines, it is necessary to evaluate the risk according to the limited geological data correctly. In this work, based on hydrogeological and mining conditions, we established a risk evaluation model and selected seven important factors, including the aquifer thickness, aquifer water abundance, hydraulic pressure of the aquifer, effective aquifuge thickness, mining failure ratio, mining height of the working face, and advancing distance as evaluation indexes. The intuitionistic fuzzy analytic hierarchy process (IFAHP) and entropy weight method (EWM) were used to analyze the weights of the original data, and the minimum information entropy principle was used to further integrate the abovementioned calculation results. With the weight results, set pair analysis-variable fuzzy set (SPA-VFS) theory was applied to determine the risk grade of each working face, which provided scientific guidance for the safe mining of coal mines. For the working face where water inrush may occur, the risk of bed separation water inrush can be reduced by optimizing the parameters or changing the mining conditions through the model analysis.

18.
ACS Omega ; 6(50): 34596-34605, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34963944

RESUMO

Coal mining under thick loose strata in North China leads to ground subsidence, which is a natural result of hydromechanical coupling (fluid flow coupled with solid deformation). Therefore, the land surrounding the mining areas is greatly damaged. In this study, the combined weight (CW) method and the fuzzy matter-element analysis (FMEA) method were used to analyze and evaluate the control effect of subsiding land. Overall, 20 sets of geological samples were collected from this area. The influencing factors and the corresponding weights for the control effect of subsiding land were comprehensively analyzed, and an FMEA model was built to predict and verify the results. The results showed that (1) the two evaluation indicators with the most significant impact on land reclamation were the degree of integration and the economic and social benefits and (2) among the 20 sets of samples selected, the predicted conclusions of 17 sets were consistent with the actual engineering situations, which led to an accuracy of 85%. In other words, the CW-FMEA model showed good reliability for evaluating the control effect of subsiding land, which can provide scientific references for control and quality evaluations of land subsidence due to coal mining.

19.
ACS Omega ; 6(50): 35144, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34963995

RESUMO

[This corrects the article DOI: 10.1021/acsomega.0c03535.].

20.
Appl Geogr ; 1322021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34121782

RESUMO

Social scientists routinely rely on methods of interpolation to adjust available data to their research needs. Spatial data from different sources often are based on different geographies that need to be reconciled, and some boundaries (e.g., administrative or political boundaries) change frequently. This study calls attention to the potential for substantial error in efforts to harmonize data to constant boundaries using standard approaches to areal and population interpolation. The case in point is census tract boundaries in the United States, which are redefined before every decennial census. Research on neighborhood effects and neighborhood change rely heavily on estimates of local area characteristics for a consistent area of time, for which they now routinely use estimates based on interpolation offered by sources such as the Neighborhood Change Data Base (NCDB) and Longitudinal Tract Data Base (LTDB). We identify a fundamental problem with how these estimates are created, and we reveal an alarming level of error in estimates of population characteristics in 2000 within 2010 boundaries. We do this by comparing estimates from one of these sources (the LTDB) to true values calculated by re-aggregating original 2000 census microdata to 2010 tract areas. We then demonstrate an alternative approach that allows the re-aggregated values to be publicly disclosed, using "differential privacy" (DP) methods to inject random noise that meets Census Bureau standards for protecting confidentiality of the raw data. We show that the DP estimates are considerably more accurate than the LTDB estimates based on interpolation, and we examine conditions under which interpolation is more susceptible to error. This study reveals cause for greater caution in the use of interpolated estimates from any source. Until and unless DP estimates can be publicly disclosed for a wide range of variables and years, research on neighborhood change should routinely examine data for signs of estimation error that may be substantial in a large share of tracts that experienced complex boundary changes.

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