71 research outputs found

    The role of arts therapies in mitigating Sleep Initiation and Maintenance Disorders: a systematic review

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    IntroductionArts therapies offer effective non-pharmacological intervention for Sleep Initiation and Maintenance Disorders (SIMDs), encompassing both passive and active modalities. This review assesses their effectiveness and ethical considerations, focusing on music therapy, meditation, and Tai Chi.MethodsFollowing PRISMA guidelines, a detailed search across PubMed, the Cochrane Library, Web of Science, and CNKI identified 17 relevant RCTs. Utilizing the Joanna Briggs Institute (JBI) quality criteria and the PICO(S) framework for data extraction ensured methodological integrity.ResultsAnalysis shows arts therapies significantly improve sleep quality. Music therapy and meditation yield immediate benefits, while Tai Chi and Qigong require longer commitment for significant outcomes. DiscussionThe link between SIMDs and mental health issues like anxiety, stress, and depression suggests arts therapies not only enhance sleep quality but also address underlying mental health conditions. The evidence supports a wider adoption of arts therapies in treating SIMDs due to their dual benefits.Systematic review registrationPROSPERO, ID: CRD42024506393

    Damage evolution characteristics of 3D-reconstructed coal during loading and its size effects based on CT scanning

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    Coal is a porous material containing pore structures and mineral components, exhibiting pronounced anisotropy and size effects.In order to investigate the influence of coal anisotropy and size effects on its failure characteristics, this paper proposes a simulation method for characterizing and reconstructing three-dimensionally the internal pores and mineral components of coal samples based on CT scanning, nuclear magnetic resonance, and X-ray diffraction.Specifically, we obtained simulation parameters of three-dimensional reconstruction models of coal matrix and mineral components through inverse laboratory uniaxial compression experiments, while simulated and analyzed the strength damage characteristics of coal bodies with different aspect ratios.The simulation results show that: ① During the loading process, the plastic zone first gradually expands and connects outward around the pores and mineral components.In terms of spatial distribution, the plastic zone expands vertically from the loading end to the interior in the early stage, and in the later stage, it expands horizontally from the surroundings to the interior.After the model is damaged, a "double truncated cone structure" is formed in the non-plastic zone.② The increase of aspect ratio leads to an increase in the compressive strength(p) of coal samples, the strain(ζ) at yielding strength, and the elastic modulus(K), among which ζ and K increase linearly, while the margin of increase in p gradually decreases.③ The total energy and elastic energy of coal sample loading increase exponentially, while the dissipated energy increases linearly.The increase of aspect ratio leads to an increase both in the accumulated elastic energy in the coal body and in the released energy during failure, which easily induce dynamic impact-related disasters.This study provide references for the reasonable selection of coal pillar size in impact mine pressure area

    Damage characteristics and mechanical properties of superhigh-water material consolidated body under triaxial stress

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    In order to study the damage characteristics of superhigh-wate consolidated body under triaxial stress state, uniaxial experiments of superhigh-water consolidated body under different curing time (1, 7, 14, 21, 28 d) were carried out. Uniaxial compression models under different curing times were established by the parallel bonding model of PFC3D, and five groups of uniaxial strength of PFC3D simulation experiment were obtained, which were consistent with the uniaxial strength of the uniaxial experiment. Statistics each simulation experiment of uniaxial compression parallel bond, mesoscopic physical and mechanical parameters in the model on the basis of the parameters under different curing time, superhigh-water consolidation triaxial compression model body, the same confining pressure and axial stress is applied, record the triaxial experiments under different curing time in the process of stress-strain curve and the force when the damage distribution chain. Analyzed superhigh-water body of consolidation in the damage characteristics of three to the stress state, the results show that: ① the superhigh-water concretion body three to the stress state of the changing rule of the ultimate strength with curing time can be represented by the Bohr boltzmann equation. When curing time is 1 to 14 days, the ultimate strength increases fastest, and the maximum ultimate strength reaches 3.1 MPa when curing time is 28 days. ② The variation rule of the degree of penetration of force chains in the triaxial compression model of superhigh-water consolidated body with curing time is as follows: within curing time of 1-28 d, the number of transverse contact force chains is 4 006, 4 561, 4 891, 5 017, 5 062, respectively. The number of longitudinal contact force chains is 4 029, 4 439, 4 716, 4 917 and 5 123. The results show that the carrying capacity of the superhigh-water consolidated body increases with the increase of curing time, and increases fastest during the curing time from 0 to 14 days, and tends to be stable during 14 to 28 days. ③ The tensile chain was used to simulate the fracture development in the triaxial compression model of superhigh-water consolidated body. The results show that the cracks concentrate on the upper and lower ends of the specimen when the curing time is 1 d. With the increase of curing time, the cracks in the middle of the specimen begin to increase and finally connect with the cracks at the upper and lower ends of the specimen

    Research on the Floor Rockburst of Panel Entry under the Mining Influence: A Case Study

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    AbstractThe stability of the entries of longwall panels is the key to ensure efficient and safe production of coal mines. In order to solve the common problems of floor heave of panel entry in western China, based on a case study, this paper studies the rockburst instability mechanism of entry floor-induced mining by considering the results from a laboratory test, numerical simulations, and field practice. After testing, the coal and rock of the entry are hard and brittle. In particular under the action of impact dynamic load, its dynamic strength is higher and has a positive correlation with the impact pressure, which provides a mechanical premise for subsequent rockburst. Numerical simulation results show that with the mining of the panel, the vertical stress and the maximum principal stress of the floor are mainly concentrated in the coal pillar along the entry, and the area and degree of concentration continue to increase. The horizontal stress is mainly concentrated in the entry floor, which is distributed in the advanced range of the panel. The deformation rate of the entry roof and the ribs is stable, while the floor shows a “mutation” characteristic of not deforming when the panel is far away and suddenly rising when it is closer to the panel. The range of the plastic zone of the roof and floor remains unchanged, the ribs are further deepened, and the mechanical properties of the coal and rock mass are further weakened. The results of this study contribute to providing a reference for the control of surrounding rock of panel entry under similar geological and geotechnical circumstances

    Experimental Research on the Effect of Bedding Angle on the Static and Dynamic Behaviors of Burst-Prone Sandstone

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    AbstractIn order to understand the mechanism of some unconventional failures such as rockburst caused by deep rock excavation, the failure characteristics of burst-prone sandstone specimens under static and dynamic loads were studied by using the MTS816 rock mechanics testing system and the split Hopkinson pressure bar (SHPB) experimental system, as well as the effects of bedding angle and impact pressure on rock mechanical properties and failure patterns. The uniaxial compression test used a cylindrical specimen with a height of 50 mm and a diameter of 100 mm, and cylindrical specimens with height and diameter of 50 mm were adopted in the SHPB tests. The bedding angles in the tests are 0°, 45°, and 90°. In the dynamic impact test, three different impact pressures were applied to observe the magnitude of impact load on the mechanical behaviors of the burst-prone sandstone specimens. The results show that with the increase in the bedding angle, the uniaxial compressive strength firstly decreases and then increases. When the bedding angle is 45°, the uniaxial compressive strength is the lowest. The uniaxial compressive strength is highest when the bedding angle is 0°. The burst-prone sandstone specimens with different bedding angles had three different failure pattern types. Under the dynamic loading, the stress-strain curves show springback phenomenon; with the increase in impact pressure, the dynamic strength of the burst-prone sandstone specimens with each bedding angle increases; the fracture degree of the bedding sandstone specimens gradually increases. The dynamic strength of the 45° burst-prone sandstone specimen is the lowest, and it has the highest fracture degree

    Biocompatibility of subretinal parylene-based Ti/Pt microelectrode array in rabbit for further artificial vision studies

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    To evaluate the biocompatibility of subretinal implanted parylene-based Ti/Pt microelectrode arrays (MEA). Eyes were enucleated 3 months after MEAs were implanted into the subretinal space of rabbits. Morphological changes of the retinas were investigated by H&E staining. Immunohistochemical staining for glial fibrillary acidic protein and opsin were performed to evaluate changes in Muller cells and photoreceptors in the retinas. Retina tissue around the array remained intact. Photoreceptor degeneration and glial cell activation were observed in the retina overlaying the MEA implant. However, the cells in the inner retinal layers were preserved. Photoreceptor degeneration and glial cell activation at the MEA–retina interface are expected to be a normal reaction to implantation. Material used in this experiment has good biocompatibility within the subretinal environment and is expected to be promising in the further retinal prosthesis studies

    CO<sub>2</sub> Storage and Geothermal Extraction Technology for Deep Coal Mine

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    This paper aims at reducing greenhouse gas emissions, which contributes to carbon neutrality, and, at the same time, preventing mine heat disasters and extracting highly mineralized (HM) mine water, so as to realize the synergy between CO2 storage (CS) and geothermal extraction and utilization (GEU) in a high temperature (HT) goaf. With this purpose, an innovative CS-GEU technology for HT and HM water in deep mine is proposed, based on the mechanism of water-rock-CO2 effect (WRCE) and the principle of GEU in the mine. This technology uses GEU to offset the costs of CO2 storage and refrigeration in HT mine. A general scheme for a synergistic system of CS and GEU in the goaf is designed. The feasibility of CS-GEU technology in the deep goaf is demonstrated from the views of CS and GEU in the goaf and the principles of a synergistic system. It is clarified that the CO2 migration-storage evolution and the multi-field coupling principle in the goaf are the key scientific issues in realizing the synergic operation of CS and GEU. It proposes the key techniques involved in this process: CO2 capture and CO2 transportation, layout and support of drill holes and high-pressure (HP) pipelines, and HP sealing in the goaf. The research results provide new ideas for CS and GEU of HT and HM mine water in deep mine

    Practice and prospect of fully mechanised mininig technology for thin coal seams under complex conditions in China

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    In China, thin coal seam are rich in resources and complex in conditions, however, the characteristics such as narrow mining space, the low level of mechanised technology, bad working environment and the high cost of mining, directly restrict the development of mining safety and high-efficiency. In thin coal seams with hard gangue which contains concretions of pyrite, LS-DYNA is applied to calculate the rational blasting parameters and carry out the deep-hole pre-splitting blasting technology, the hard gangue is fractured effectively, hence advancing the productivity of thin coal seam mining. In addition, the mining rate is sped up in thin protective layers in extreme close coal seams by enhancing the level of fully mechanised equipment and other effective measures. Safety and high-efficiency mining can be realised in the outburst coal seam. Thin coal seam mining technology faces many problems presently, i.e. the low level of equipment automation, the low advance rate of mixed coal-rock drift, and the big intensity of worker labour. By lowering the labour intensity, improving the efficiency by means of advancing mining automatic equipment and other measures, respectively, thus manless working faces can be successfully realised in thin coal seam mining

    Practice and Prospect of Fully Mechanised Mining Technology for Thin Coal Seams under Complex Conditions in China

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    In China, thin coal seam are rich in resources and complex in conditions, however, the characteristics such as narrow mining space, the low level of mechanised technology, bad workingenvironment and the high cost of mining, directly restrict the development of mining safety andhigh-efficiency. In thin coal seams with hard gangue which contains concretions of pyrite, LS-DYNA isapplied to calculate the rational blasting parameters and carry out the deep-hole pre-splitting blastingtechnology, the hard gangue is fractured effectively, hence advancing the productivity of thin coal seammining. In addition, the mining rate is speeded up in thin protective layers in extreme close coal seams byenhancing the level of fully mechanised equipment and other effective measures. Safety andhigh-efficiency mining can be realised in the outburst coal seam. Thin coal seam mining technology facesmany problems presently, i.e. the low level of equipment automation, the low advance rate of mixedcoal-rock drift, and the big intensity of worker labour. By lowering the labour intensity, improving theefficiency by means of advancing mining automatic equipment and other measures, respectively, thusmanless working faces can be successfully realised in thin coal seam mining

    Advanced directional drilling technology for gas drainage and exploration in Australian coal mines

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    With the continuing technology innovation, directional drilling technology has provided the coal mining industry with effective and practical options for pre- and post-drainage and exploration in Australia. In the past thirty years, in-mine borehole steering equipment has been developed from the single shot camera survey systems to the advanced Directional Drill Monitor utilizing Modular Electrically Connected Cable Assembly (DDM-MECCA) survey instruments, which provides rapid and easy underground borehole survey measurements whilst drilling. The presence of coal seam gas such as methane poses a significant safety hazard to underground coal mining all over the world. However, gas can be captured using pre- and post-drainage techniques to improve coal production, energy recovery, enhance safety, environmental mitigation. An additional benefit of directional drilling is geological explorations in advance of mining. As any discontinuities intercepted during in-seam directional drilling, such as faults, folds and igneous intrusions, can be monitored by drilling fluid pressures, changes in thrust, vibration, rate of penetration and inspection of cuttings. Directional drilling technologies offer coal operators a cost effective exploration alternative without speculation. Applications of the directional drilling technologies in Australian coal mines have established the benefits of the methodology for gas control and geological explorations. Directionally drilled flank boreholes provide shielding to the gate entry developments, horizontal goaf boreholes for gas drainage in deep multi-level mines, and hydro fracturing and exploration in advance of mining. However, there still remains four major problems associated with directionally drilling, and these include: sticky drilling in complex conditions, sensitivity of down hole probe, in-hole stability and drill depth capacity
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