A shortage of courtrooms has long been a challenge in Malawi,especially since more judges were hired to help to streamline the country’s judicial process.Yet,while the current judiciary is headquartered in the countr...A shortage of courtrooms has long been a challenge in Malawi,especially since more judges were hired to help to streamline the country’s judicial process.Yet,while the current judiciary is headquartered in the country’s second-largest city of Blantyre,due to a lack of work space;some sections of the judiciary are located elsewhere,such as the juvenile,commercial and industrial courts.展开更多
Mining-induced fracture zone will be produced in the overlying strata after the coal was mined.In this article,the mining-induced deformation of overlying strata and the time-space evolution law of fissure were studie...Mining-induced fracture zone will be produced in the overlying strata after the coal was mined.In this article,the mining-induced deformation of overlying strata and the time-space evolution law of fissure were studied by the methods of physical simulation and field measurement.The results show that bed separation fissure and vertical fissure will appear in the overlying strata above mining face,which form the wedge-shaped fissure zone.The open degree of fissure depends on the size of uncoordinated deformation between neighbor layers,and the absolute strata sinking controls both the width of bed separation zone and the open degree of vertical breakage fissure.At last,the calculating formula was deducted based on theoretical analysis.展开更多
Based on specific geology and mining conditions of certain coal working face in China, a series of numerical models under different unconsolidated layers thickness were respectively established by employing FLAC3D. Th...Based on specific geology and mining conditions of certain coal working face in China, a series of numerical models under different unconsolidated layers thickness were respectively established by employing FLAC3D. The relationship between the unconsolidated layers thickness and surface movement laws was studied. Maximum surface subsidence, Maximum horizontal displacement and surface subsidence degree were obtained. Contours of surface subsidence/horizontal displacement and curves were drawn. Some laws of surface subsidence/horizontal displacement were analyzed. The role of the unconsolidated layers in surface subsidence was revealed. It is significant to predict surface subsidence of thick unconsolidated layers for coal mine and take effective measures to control surface subsidence.展开更多
The strata movement induced by sub-critical extraction is a problem not receiving due attention because of its relatively small magnitude of deformation. However, with the increase of mining depth, sub-critical extrac...The strata movement induced by sub-critical extraction is a problem not receiving due attention because of its relatively small magnitude of deformation. However, with the increase of mining depth, sub-critical extraction has become a general phenomenon. This calls for an in-depth investigation into the characteristics of ground movements observed under different extents of sub-critical extraction, so as to determine the appropriate mining technique for use. Following a discussion of the factors influencing the extent of super-critical extraction, the super-critical extraction extent evaluation criteria was presented, the characteristics and laws of the strata and ground movements caused by such an extraction condition were systematically analyzed, and the mechanism of surface subsidence induced by sub-critical extraction was revealed. The result of study may serve as a basis for the development of the strata and ground movement prediction model and the mining techniques appropriate for use at depth beneath surface structures and buildings.展开更多
When mining the fully-mechanized longwall caving face along strike, the unstable equipment, the low top-coal recovery ratio and the difficulty in controlling surrounding rock may occur due to large dip angle. Consider...When mining the fully-mechanized longwall caving face along strike, the unstable equipment, the low top-coal recovery ratio and the difficulty in controlling surrounding rock may occur due to large dip angle. Considering the effects of strike angle on support stability, the ‘‘support-surrounding rock"mechanical models of support topple and support slip were established in this paper. On the basis, the influencing factors of support stability were analyzed and the technical measures of controlling support and surrounding rock stability were put forward. Then the loose particles simulation experiment was conducted to analyze the impacts of caving directions and methods on the top-coal recovery in large dip angle fully-mechanized caving face. Finally, the ‘‘upward sequence and double-openings doublerounds" caving technology was determined. The research results are of great scientific significance and practical values to improve large dip thick seam mining technology.展开更多
Based on the results of similar material simulation, the laws of slope movementdue to mining under a gully were analyzed. Selected a slope rock as objective, the mechanisms of slope movement influence upon underground...Based on the results of similar material simulation, the laws of slope movementdue to mining under a gully were analyzed. Selected a slope rock as objective, the mechanisms of slope movement influence upon underground mining were proposed, and respective structural models were built by means of numerical modeling and physical simulation.It holds the point that the influence of slope movement on underground mining could becontrolled to some extent by appropriate measures. The results indicate that, forgully-ward mining, which mines toward a gully, the slope rock slides horizontally and rotates in layers; for gully-away mining, which mines away from the gully, the slope rock rotates in a reversed polygon. The slope movement associated with mining under a gully isattributed to pre-existing free faces in the ground gully and underground mining-inducedfree faces.展开更多
We combined the similar simulation with numerical simulation to analyze the movement and deforma- tion features of overlying strata caused by paste backfill mining, study the movement and deformation laws of the overl...We combined the similar simulation with numerical simulation to analyze the movement and deforma- tion features of overlying strata caused by paste backfill mining, study the movement and deformation laws of the overlying strata in paste backfill mining, structural movement of the stope strata as well as the stope stress distribution laws. Furthermore, authors also explored the key factors to the movement and deformation of the overlying strata in paste backfill mining. The results indicate that a caving zone existed in the bending zone only in the overlying strata of the paste backfill mining. Compared with the roof caving mining, the degree of stress concentration and area of influence in the paste filling stope were apparently smaller. And the degree of destruction and area of the overlying strata decreased prominently. Also, there was no apparent strata behavior in the working face. Lastly, the filling ratio was the key to control the movement and deformation of the overlying strata. Combined with a specific engineering example, the author proved the reliability of the simulation results and provided a theoretical basis for the further extension of the paste backfill mining.展开更多
According to the problem during mining coal seam with high gas and its control, the theory numerical calculation of gas and strata movement law caused by protection layer mining was studied, with the background of Sna...According to the problem during mining coal seam with high gas and its control, the theory numerical calculation of gas and strata movement law caused by protection layer mining was studied, with the background of Snake Mountain coal mine. First of all, the basic principle of fluid(gas)-solid coupling was briefly described, and a three dimensional model was established by FLAC software. Secondly, the calculation parameters of fluid-solid coupling were obtained based on the measured data, and the numerical calculation of sublevel mining was carried out in turn. Lastly, initial stress state, gas movement law, deformation law of pore pressure and movement characteristics of rock strata were studied, respectively. The results show that the gas and pressure were greatly reduced with the advance of 4 coal seam working surface, as well as the constant increase of area of goaf. Facilitating gas and the stress were gradually penetrated and released to goaf during the whole process of mining. The gas pressure, the aggregation degree and the surrounding rock pressure of the 1 coal seam and the 3 coal seam were greatly reduced.展开更多
It is an important part of green mining to control the disasters of coal mining which have caused irreversible damages to buildings and ecological environment. Strip mining is one of the efficient measures to control ...It is an important part of green mining to control the disasters of coal mining which have caused irreversible damages to buildings and ecological environment. Strip mining is one of the efficient measures to control surface subsidence and mining damage. However, the research on the laws of the surface subsidence are still deficient in multi-coal seam strip mining at present. Based on the Fast Lagrangian Analysis of Continua(short for FLAC3D) numerical simulation software, the laws of the surface subsidence and horizontal movement were systematically studied for different depths, different mining widths, different distances between seams, different mining thickness, different parameters between seams and the special relations of the upper pillar and the lower pillar in the vertical direction in multi-seam strip mining. The function relation between the maximum subsidence and the maximum horizontal movement with the depth, the mining width, the seam distance, mining thickness, different parameters between seams and the partial offset are summarized respectively. Finally the formula integrating the surface maximum subsidence value and the maximum horizontal movement was deduced. The results can be used for reference theory and measure in forecasting the surface displacement in multi-coal seam strip mining.展开更多
Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relati...Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relationship between research funding and citations of papers using 831,337 documents recorded in the Web of Science database.Findings:The original results reveal general characteristics of the diffusion of science in research fields:a)Funded articles receive higher citations compared to unfunded papers in journals;b)Funded articles exhibit a super-linear growth in citations,surpassing the increase seen in unfunded articles.This finding reveals a higher diffusion of scientific knowledge in funded articles.Moreover,c)funded articles in both basic and applied sciences demonstrate a similar expected change in citations,equivalent to about 1.23%,when the number of funded papers increases by 1%in journals.This result suggests,for the first time,that funding effect of scientific research is an invariant driver,irrespective of the nature of the basic or applied sciences.Originality/value:This evidence suggests empirical laws of funding for scientific citations that explain the importance of robust funding mechanisms for achieving impactful research outcomes in science and society.These findings here also highlight that funding for scientific research is a critical driving force in supporting citations and the dissemination of scientific knowledge in recorded documents in both basic and applied sciences.Practical implications:This comprehensive result provides a holistic view of the relationship between funding and citation performance in science to guide policymakers and R&D managers with science policies by directing funding to research in promoting the scientific development and higher diffusion of results for the progress of human society.展开更多
In this paper, the law of roof-coal movement has been investigated through the field measurement, theoretical analysis and numerical calculation. Several results, which are of important values for caving process, desi...In this paper, the law of roof-coal movement has been investigated through the field measurement, theoretical analysis and numerical calculation. Several results, which are of important values for caving process, design of the supports, controlling end-face stability, raising recovery rate, realizing working face high output and other related aspects in practice, have been obtained. These results mainly include the following: roof-coal breaking curve of soft-coal seam, roof-coal movement curve of soft-coal and medium-hard coal seam, and roof-coal movement equation. The roof-coal caveability has been analyzed.展开更多
Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain a...Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain an illegitimate benefit or createmisleading publicity by using tempered images.Exiting forgery detectionmethods can classify only one of the most widely used Copy-Move and splicing forgeries.However,an image can contain one or more types of forgeries.This study has proposed a hybridmethod for classifying Copy-Move and splicing images using texture information of images in the spatial domain.Firstly,images are divided into equal blocks to get scale-invariant features.Weber law has been used for getting texture features,and finally,XGBOOST is used to classify both Copy-Move and splicing forgery.The proposed method classified three types of forgeries,i.e.,splicing,Copy-Move,and healthy.Benchmarked(CASIA 2.0,MICCF200)and RCMFD datasets are used for training and testing.On average,the proposed method achieved 97.3% accuracy on benchmarked datasets and 98.3% on RCMFD datasets by applying 10-fold cross-validation,which is far better than existing methods.展开更多
Background:Emerging adulthood is a pivotal life stage,presenting significant psychological and social changes,such as decreased sociability,depression,and other mental health problems.Previous studies have associated ...Background:Emerging adulthood is a pivotal life stage,presenting significant psychological and social changes,such as decreased sociability,depression,and other mental health problems.Previous studies have associated these changes with an unhealthy lifestyle.The 24-h movement guidelines for healthy lifestyles have been developed to promote appropriate health behaviors and improve individual wellness.However,the relationship between adherence to the 24-h movement guidelines and different characteristics of Chinese emerging adults is yet to be explored.This cross-sectional study aimed to investigate the association between adherence to the 24-h movement guidelines and four characteristics(self-exploration,instability,possibilities,and responsibility)of Chinese emerging adults.Methods:Overall,1,510 Chinese emerging adults aged 18–29 years were included in this study.Each participant completed a self-administered questionnaire that included questions on adherence to the 24-h movement guidelines(physical activity,sedentary behavior,and sleep)and the inventory of dimensions of emerging adulthood.Multivariable logistic regression analysis was employed to investigate the associations between adherence to the 24-h movement guidelines and each of the four characteristics.Results:The proportion of participants who adhered to the 24-h movement guidelines was 31.72%.Multiple regression analysis revealed a significantly negative relationship between adhering to more guidelines and instability(β=−0.51,p<0.001).A statistically significant association was observed between instability and meeting only sedentary behavior(β=−1.27,95%confidence interval[CI]:[−2.32,−0.24],p=0.02),sedentary behavior+sleep(β=−1.30,95%CI:[−2.24,−0.35],p<0.01),and physical activity+sedentary behavior(β=−1.08,95%CI:[1.94,−0.21],p=0.02)guidelines.Further,positive and significant associations were observed between possibilities and meeting the guidelines for only physical activity(β=0.70,95%CI:[0.14,1.27),p=0.01),only sleep(β=0.61,95%CI:[0.01,1.21],p=0.04),physical activity+sedentary behavior(β=0.56,95%CI:[0.04,1.07),p=0.01),and physical activity+sleep(β=0.76,95%CI:[0.23,1.27],p=0.01).Conclusions:These findings suggest that adherence to the 24-h movement guidelines was associated with instability in Chinese emerging adults.Future studies are warranted to verify our findings to highlight the importance of maintaining a heath lifestyle to promote health in emerging adulthood.展开更多
With the discrete element method, the simulation and analysis of a series of numerical models were made. This research revealed ground movement laws for strip mining under thick alluvium and gave calculation formulae ...With the discrete element method, the simulation and analysis of a series of numerical models were made. This research revealed ground movement laws for strip mining under thick alluvium and gave calculation formulae for the maximum ground subsidence and horizontal movement as a function of basement rock thickness and mining width, thus providing sound evidence for future strip mining under thick alluvium.展开更多
The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of G...The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions.展开更多
Pyroptosis,an inflammatory caspase-dependent programmed cell death,plays a vital role in maintaining tissue homeostasis and activating inflammatory responses.Orthodontic tooth movement(OTM)is an aseptic force-induced ...Pyroptosis,an inflammatory caspase-dependent programmed cell death,plays a vital role in maintaining tissue homeostasis and activating inflammatory responses.Orthodontic tooth movement(OTM)is an aseptic force-induced inflammatory bone remodeling process mediated by the activation of periodontal ligament(PDL)progenitor cells.However,whether and how force induces PDL progenitor cell pyroptosis,thereby influencing OTM and alveolar bone remodeling remains unknown.In this study,we found that mechanical force induced the expression of pyroptosis-related markers in rat OTM and alveolar bone remodeling process.Blocking or enhancing pyroptosis level could suppress or promote OTM and alveolar bone remodeling respectively.Using Caspase-1^(−/−)mice,we further demonstrated that the functional role of the force-induced pyroptosis in PDL progenitor cells depended on Caspase-1.Moreover,mechanical force could also induce pyroptosis in human ex-vivo force-treated PDL progenitor cells and in compressive force-loaded PDL progenitor cells in vitro,which influenced osteoclastogenesis.Mechanistically,transient receptor potential subfamily V member 4 signaling was involved in force-induced Caspase-1-dependent pyroptosis in PDL progenitor cells.Overall,this study suggested a novel mechanism contributing to the modulation of osteoclastogenesis and alveolar bone remodeling under mechanical stimuli,indicating a promising approach to accelerate OTM by targeting Caspase-1.展开更多
1.Background The Olympic motto,"Faster,Higher,Stronger-Together",represents the pursuit of athletic excellence,united as a global community."Excellence,respect and friendship"are the Olympic values...1.Background The Olympic motto,"Faster,Higher,Stronger-Together",represents the pursuit of athletic excellence,united as a global community."Excellence,respect and friendship"are the Olympic values.Both the motto and values are multifaceted and holistic in nature,and all-encompassing in their reach while recognizing no single entity rises above the others.Collectively,these foundational statements anchor the Olympic movement in its quest to build a better world through sport.展开更多
The utilization of optimal orthodontic force is crucial to prevent undesirable side effects and ensure efficient tooth movement during orthodontic treatment.However,the sensitivity of existing detection techniques is ...The utilization of optimal orthodontic force is crucial to prevent undesirable side effects and ensure efficient tooth movement during orthodontic treatment.However,the sensitivity of existing detection techniques is not sufficient,and the criteria for evaluating optimal force have not been yet established.Here,by employing 3D finite element analysis methodology,we found that the apical distal region(A-D region)of mesial roots is particularly sensitive to orthodontic force in rats.Tartrate-resistant acidic phosphatase(TRAP)-positive osteoclasts began accumulating in the A-D region under the force of 40 grams(g),leading to alveolar bone resorption and tooth movement.When the force reached 80 g,TRAP-positive osteoclasts started appearing on the root surface in the A-D region.Additionally,micro-computed tomography revealed a significant root resorption at 80 g.Notably,the A-D region was identified as a major contributor to whole root resorption.It was determined that 40 g is the minimum effective force for tooth movement with minimal side effects according to the analysis of tooth movement,inclination,and hyalinization.These findings suggest that the A-D region with its changes on the root surface is an important consideration and sensitive indicator when evaluating orthodontic forces for a rat model.Collectively,our investigations into this region would aid in offering valuable implications for preventing and minimizing root resorption during patients’orthodontic treatment.展开更多
1.Background The importance of physical activity(PA)for health is unequivocal.^(1)Accordingly,population-based recommendations for exercise,and more recently public health guidelines for PA,have been developed and rel...1.Background The importance of physical activity(PA)for health is unequivocal.^(1)Accordingly,population-based recommendations for exercise,and more recently public health guidelines for PA,have been developed and released by authoritative groups for many decades.^(2)Such guidelines emerged with leadership from the exercise physiology discipline and were rooted in,and loyal to,the importance of moderate-to-vigorous intensity PA(MVPA)or exercise.展开更多
Introduction:Parkinson’s disease(PD)is the most common neurodegenerative movement disorder.The pathological hallmark is the progressive loss of dopaminergic neurons of the substantia nigra pars compacta,which is acco...Introduction:Parkinson’s disease(PD)is the most common neurodegenerative movement disorder.The pathological hallmark is the progressive loss of dopaminergic neurons of the substantia nigra pars compacta,which is accompanied by widespread alterations in the structu re and function of distributed brain networks.Togethe r,these processes cause a variety of motor symptoms such as bradykinesia,rigidity,tremor,gait disorders,or difficulties in fine motor control(Bange et al.,2022).展开更多
文摘A shortage of courtrooms has long been a challenge in Malawi,especially since more judges were hired to help to streamline the country’s judicial process.Yet,while the current judiciary is headquartered in the country’s second-largest city of Blantyre,due to a lack of work space;some sections of the judiciary are located elsewhere,such as the juvenile,commercial and industrial courts.
文摘Mining-induced fracture zone will be produced in the overlying strata after the coal was mined.In this article,the mining-induced deformation of overlying strata and the time-space evolution law of fissure were studied by the methods of physical simulation and field measurement.The results show that bed separation fissure and vertical fissure will appear in the overlying strata above mining face,which form the wedge-shaped fissure zone.The open degree of fissure depends on the size of uncoordinated deformation between neighbor layers,and the absolute strata sinking controls both the width of bed separation zone and the open degree of vertical breakage fissure.At last,the calculating formula was deducted based on theoretical analysis.
基金Project(2007BAK28B03)supported by the National Eleventh-Five Year Research Program of ChinaProject(2010YD05)supported by the Fundamental Research Funds for the Central UniversitiesProject(200911036)supported by the Ministry of Land and Resources Research Special
文摘Based on specific geology and mining conditions of certain coal working face in China, a series of numerical models under different unconsolidated layers thickness were respectively established by employing FLAC3D. The relationship between the unconsolidated layers thickness and surface movement laws was studied. Maximum surface subsidence, Maximum horizontal displacement and surface subsidence degree were obtained. Contours of surface subsidence/horizontal displacement and curves were drawn. Some laws of surface subsidence/horizontal displacement were analyzed. The role of the unconsolidated layers in surface subsidence was revealed. It is significant to predict surface subsidence of thick unconsolidated layers for coal mine and take effective measures to control surface subsidence.
基金Project supported by Doctoral Study Courses Foundation and Post-Doctoral Scientific Foundation .
文摘The strata movement induced by sub-critical extraction is a problem not receiving due attention because of its relatively small magnitude of deformation. However, with the increase of mining depth, sub-critical extraction has become a general phenomenon. This calls for an in-depth investigation into the characteristics of ground movements observed under different extents of sub-critical extraction, so as to determine the appropriate mining technique for use. Following a discussion of the factors influencing the extent of super-critical extraction, the super-critical extraction extent evaluation criteria was presented, the characteristics and laws of the strata and ground movements caused by such an extraction condition were systematically analyzed, and the mechanism of surface subsidence induced by sub-critical extraction was revealed. The result of study may serve as a basis for the development of the strata and ground movement prediction model and the mining techniques appropriate for use at depth beneath surface structures and buildings.
基金provided by the National Key Basic Research Program of China (973 Program) (No. 2015CB251600)the Qing Lan Projectthe Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘When mining the fully-mechanized longwall caving face along strike, the unstable equipment, the low top-coal recovery ratio and the difficulty in controlling surrounding rock may occur due to large dip angle. Considering the effects of strike angle on support stability, the ‘‘support-surrounding rock"mechanical models of support topple and support slip were established in this paper. On the basis, the influencing factors of support stability were analyzed and the technical measures of controlling support and surrounding rock stability were put forward. Then the loose particles simulation experiment was conducted to analyze the impacts of caving directions and methods on the top-coal recovery in large dip angle fully-mechanized caving face. Finally, the ‘‘upward sequence and double-openings doublerounds" caving technology was determined. The research results are of great scientific significance and practical values to improve large dip thick seam mining technology.
基金Supported by the Program for New Century Excellent Talents in University (NCET-05-0480)Gradute Student Scientific Research Innovation in University of Jiangsu Province
文摘Based on the results of similar material simulation, the laws of slope movementdue to mining under a gully were analyzed. Selected a slope rock as objective, the mechanisms of slope movement influence upon underground mining were proposed, and respective structural models were built by means of numerical modeling and physical simulation.It holds the point that the influence of slope movement on underground mining could becontrolled to some extent by appropriate measures. The results indicate that, forgully-ward mining, which mines toward a gully, the slope rock slides horizontally and rotates in layers; for gully-away mining, which mines away from the gully, the slope rock rotates in a reversed polygon. The slope movement associated with mining under a gully isattributed to pre-existing free faces in the ground gully and underground mining-inducedfree faces.
基金supported by the National Natural Science Foundation of China (No. 50774077)the Special Funds of Universities Outstanding Doctoral Dissertation (No. 200760)+1 种基金the Independent Research Funding of the State Key Laboratory of Coal Resources and Mine Safety (No. SKLCRSM10X02)the Fundamental Research Funds for the Central Universities (Nos. 2010QNA31 and2010QNA32)
文摘We combined the similar simulation with numerical simulation to analyze the movement and deforma- tion features of overlying strata caused by paste backfill mining, study the movement and deformation laws of the overlying strata in paste backfill mining, structural movement of the stope strata as well as the stope stress distribution laws. Furthermore, authors also explored the key factors to the movement and deformation of the overlying strata in paste backfill mining. The results indicate that a caving zone existed in the bending zone only in the overlying strata of the paste backfill mining. Compared with the roof caving mining, the degree of stress concentration and area of influence in the paste filling stope were apparently smaller. And the degree of destruction and area of the overlying strata decreased prominently. Also, there was no apparent strata behavior in the working face. Lastly, the filling ratio was the key to control the movement and deformation of the overlying strata. Combined with a specific engineering example, the author proved the reliability of the simulation results and provided a theoretical basis for the further extension of the paste backfill mining.
基金Funded by the Open Research Foundation of Key Laboratory of Safety and High-efficiency Coal Mining,Ministry of Education(Anhui University of Science and Technology)(No.JYBSYS2015201)the National Natural Science Foundation of China(No.51574122)the Natural Science Foundation of Hunan Province,China(No.2017JJ2082)
文摘According to the problem during mining coal seam with high gas and its control, the theory numerical calculation of gas and strata movement law caused by protection layer mining was studied, with the background of Snake Mountain coal mine. First of all, the basic principle of fluid(gas)-solid coupling was briefly described, and a three dimensional model was established by FLAC software. Secondly, the calculation parameters of fluid-solid coupling were obtained based on the measured data, and the numerical calculation of sublevel mining was carried out in turn. Lastly, initial stress state, gas movement law, deformation law of pore pressure and movement characteristics of rock strata were studied, respectively. The results show that the gas and pressure were greatly reduced with the advance of 4 coal seam working surface, as well as the constant increase of area of goaf. Facilitating gas and the stress were gradually penetrated and released to goaf during the whole process of mining. The gas pressure, the aggregation degree and the surrounding rock pressure of the 1 coal seam and the 3 coal seam were greatly reduced.
基金Funded by the Scientific Program of Hunan Provincial Science and Technology Department(2014FJ3104)Scientific Program of Hunan Provincial Education Department(13C313)
文摘It is an important part of green mining to control the disasters of coal mining which have caused irreversible damages to buildings and ecological environment. Strip mining is one of the efficient measures to control surface subsidence and mining damage. However, the research on the laws of the surface subsidence are still deficient in multi-coal seam strip mining at present. Based on the Fast Lagrangian Analysis of Continua(short for FLAC3D) numerical simulation software, the laws of the surface subsidence and horizontal movement were systematically studied for different depths, different mining widths, different distances between seams, different mining thickness, different parameters between seams and the special relations of the upper pillar and the lower pillar in the vertical direction in multi-seam strip mining. The function relation between the maximum subsidence and the maximum horizontal movement with the depth, the mining width, the seam distance, mining thickness, different parameters between seams and the partial offset are summarized respectively. Finally the formula integrating the surface maximum subsidence value and the maximum horizontal movement was deduced. The results can be used for reference theory and measure in forecasting the surface displacement in multi-coal seam strip mining.
文摘Purpose:The goal of this study is to analyze the relationship between funded and unfunded papers and their citations in both basic and applied sciences.Design/methodology/approach:A power law model analyzes the relationship between research funding and citations of papers using 831,337 documents recorded in the Web of Science database.Findings:The original results reveal general characteristics of the diffusion of science in research fields:a)Funded articles receive higher citations compared to unfunded papers in journals;b)Funded articles exhibit a super-linear growth in citations,surpassing the increase seen in unfunded articles.This finding reveals a higher diffusion of scientific knowledge in funded articles.Moreover,c)funded articles in both basic and applied sciences demonstrate a similar expected change in citations,equivalent to about 1.23%,when the number of funded papers increases by 1%in journals.This result suggests,for the first time,that funding effect of scientific research is an invariant driver,irrespective of the nature of the basic or applied sciences.Originality/value:This evidence suggests empirical laws of funding for scientific citations that explain the importance of robust funding mechanisms for achieving impactful research outcomes in science and society.These findings here also highlight that funding for scientific research is a critical driving force in supporting citations and the dissemination of scientific knowledge in recorded documents in both basic and applied sciences.Practical implications:This comprehensive result provides a holistic view of the relationship between funding and citation performance in science to guide policymakers and R&D managers with science policies by directing funding to research in promoting the scientific development and higher diffusion of results for the progress of human society.
文摘In this paper, the law of roof-coal movement has been investigated through the field measurement, theoretical analysis and numerical calculation. Several results, which are of important values for caving process, design of the supports, controlling end-face stability, raising recovery rate, realizing working face high output and other related aspects in practice, have been obtained. These results mainly include the following: roof-coal breaking curve of soft-coal seam, roof-coal movement curve of soft-coal and medium-hard coal seam, and roof-coal movement equation. The roof-coal caveability has been analyzed.
基金funded by Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2024R236),Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain an illegitimate benefit or createmisleading publicity by using tempered images.Exiting forgery detectionmethods can classify only one of the most widely used Copy-Move and splicing forgeries.However,an image can contain one or more types of forgeries.This study has proposed a hybridmethod for classifying Copy-Move and splicing images using texture information of images in the spatial domain.Firstly,images are divided into equal blocks to get scale-invariant features.Weber law has been used for getting texture features,and finally,XGBOOST is used to classify both Copy-Move and splicing forgery.The proposed method classified three types of forgeries,i.e.,splicing,Copy-Move,and healthy.Benchmarked(CASIA 2.0,MICCF200)and RCMFD datasets are used for training and testing.On average,the proposed method achieved 97.3% accuracy on benchmarked datasets and 98.3% on RCMFD datasets by applying 10-fold cross-validation,which is far better than existing methods.
基金the Research on Youth Physical Behavior and Mental Health Problems-Department of Science and Technology of Guangdong Province(2022SB0022).
文摘Background:Emerging adulthood is a pivotal life stage,presenting significant psychological and social changes,such as decreased sociability,depression,and other mental health problems.Previous studies have associated these changes with an unhealthy lifestyle.The 24-h movement guidelines for healthy lifestyles have been developed to promote appropriate health behaviors and improve individual wellness.However,the relationship between adherence to the 24-h movement guidelines and different characteristics of Chinese emerging adults is yet to be explored.This cross-sectional study aimed to investigate the association between adherence to the 24-h movement guidelines and four characteristics(self-exploration,instability,possibilities,and responsibility)of Chinese emerging adults.Methods:Overall,1,510 Chinese emerging adults aged 18–29 years were included in this study.Each participant completed a self-administered questionnaire that included questions on adherence to the 24-h movement guidelines(physical activity,sedentary behavior,and sleep)and the inventory of dimensions of emerging adulthood.Multivariable logistic regression analysis was employed to investigate the associations between adherence to the 24-h movement guidelines and each of the four characteristics.Results:The proportion of participants who adhered to the 24-h movement guidelines was 31.72%.Multiple regression analysis revealed a significantly negative relationship between adhering to more guidelines and instability(β=−0.51,p<0.001).A statistically significant association was observed between instability and meeting only sedentary behavior(β=−1.27,95%confidence interval[CI]:[−2.32,−0.24],p=0.02),sedentary behavior+sleep(β=−1.30,95%CI:[−2.24,−0.35],p<0.01),and physical activity+sedentary behavior(β=−1.08,95%CI:[1.94,−0.21],p=0.02)guidelines.Further,positive and significant associations were observed between possibilities and meeting the guidelines for only physical activity(β=0.70,95%CI:[0.14,1.27),p=0.01),only sleep(β=0.61,95%CI:[0.01,1.21],p=0.04),physical activity+sedentary behavior(β=0.56,95%CI:[0.04,1.07),p=0.01),and physical activity+sleep(β=0.76,95%CI:[0.23,1.27],p=0.01).Conclusions:These findings suggest that adherence to the 24-h movement guidelines was associated with instability in Chinese emerging adults.Future studies are warranted to verify our findings to highlight the importance of maintaining a heath lifestyle to promote health in emerging adulthood.
基金National Natural Science Foundation of China (5 98740 2 9) and F oundation of University Key Teacher by the Min-istry of Education
文摘With the discrete element method, the simulation and analysis of a series of numerical models were made. This research revealed ground movement laws for strip mining under thick alluvium and gave calculation formulae for the maximum ground subsidence and horizontal movement as a function of basement rock thickness and mining width, thus providing sound evidence for future strip mining under thick alluvium.
基金the National Key R&D Program of China(Grant No.2022YFF0503702)the National Natural Science Foundation of China(Grant Nos.42074186,41831071,42004136,and 42274195)+1 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20211036)the Specialized Research Fund for State Key Laboratories,and the University of Science and Technology of China Research Funds of the Double First-Class Initiative(Grant No.YD2080002013).
文摘The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical application.Assessing the credibility of GIM products in data-sparse regions is of paramount importance.In this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in 2013-2014.The indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM products.Results revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error variations.These results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions.
基金supported by the National Natural Science Foundations of China No.82230030,No.81871492(Y.L.)and No.82170996(D.H.)Beijing International Science and Technology Cooperation Project No.Z221100002722003(Y.L.)+3 种基金Beijing Natural Science Foundation No.L23002,No.L234017(Y.L.)Ten-Thousand Talents Program No.QNBJ2019-2(Y.L.)Key R&D Plan of Ningxia Hui Autonomous Region No.2020BCG01001(Y.L.)Innovative Research Team of High-level Local Universities in Shanghai No.SHSMU-ZLCX20212402(Y.L.).
文摘Pyroptosis,an inflammatory caspase-dependent programmed cell death,plays a vital role in maintaining tissue homeostasis and activating inflammatory responses.Orthodontic tooth movement(OTM)is an aseptic force-induced inflammatory bone remodeling process mediated by the activation of periodontal ligament(PDL)progenitor cells.However,whether and how force induces PDL progenitor cell pyroptosis,thereby influencing OTM and alveolar bone remodeling remains unknown.In this study,we found that mechanical force induced the expression of pyroptosis-related markers in rat OTM and alveolar bone remodeling process.Blocking or enhancing pyroptosis level could suppress or promote OTM and alveolar bone remodeling respectively.Using Caspase-1^(−/−)mice,we further demonstrated that the functional role of the force-induced pyroptosis in PDL progenitor cells depended on Caspase-1.Moreover,mechanical force could also induce pyroptosis in human ex-vivo force-treated PDL progenitor cells and in compressive force-loaded PDL progenitor cells in vitro,which influenced osteoclastogenesis.Mechanistically,transient receptor potential subfamily V member 4 signaling was involved in force-induced Caspase-1-dependent pyroptosis in PDL progenitor cells.Overall,this study suggested a novel mechanism contributing to the modulation of osteoclastogenesis and alveolar bone remodeling under mechanical stimuli,indicating a promising approach to accelerate OTM by targeting Caspase-1.
文摘1.Background The Olympic motto,"Faster,Higher,Stronger-Together",represents the pursuit of athletic excellence,united as a global community."Excellence,respect and friendship"are the Olympic values.Both the motto and values are multifaceted and holistic in nature,and all-encompassing in their reach while recognizing no single entity rises above the others.Collectively,these foundational statements anchor the Olympic movement in its quest to build a better world through sport.
基金funded by the National Natural Science Foundation of China for Key Program Projects(No.82030070,to L.C.)Hubei Provincial Natural Science Fund for Creative Research(No.2020CFA014,to L.C.)+1 种基金the National Natural Science Foundation of China(No.82100960,to S.Y.)Chinese Orthodontic Society Basic Research Fund(COS-B2021-01,to M.X.).
文摘The utilization of optimal orthodontic force is crucial to prevent undesirable side effects and ensure efficient tooth movement during orthodontic treatment.However,the sensitivity of existing detection techniques is not sufficient,and the criteria for evaluating optimal force have not been yet established.Here,by employing 3D finite element analysis methodology,we found that the apical distal region(A-D region)of mesial roots is particularly sensitive to orthodontic force in rats.Tartrate-resistant acidic phosphatase(TRAP)-positive osteoclasts began accumulating in the A-D region under the force of 40 grams(g),leading to alveolar bone resorption and tooth movement.When the force reached 80 g,TRAP-positive osteoclasts started appearing on the root surface in the A-D region.Additionally,micro-computed tomography revealed a significant root resorption at 80 g.Notably,the A-D region was identified as a major contributor to whole root resorption.It was determined that 40 g is the minimum effective force for tooth movement with minimal side effects according to the analysis of tooth movement,inclination,and hyalinization.These findings suggest that the A-D region with its changes on the root surface is an important consideration and sensitive indicator when evaluating orthodontic forces for a rat model.Collectively,our investigations into this region would aid in offering valuable implications for preventing and minimizing root resorption during patients’orthodontic treatment.
基金supported in part by an anonymous donation to develop the Precision Child and Youth Mental Health Initiative
文摘1.Background The importance of physical activity(PA)for health is unequivocal.^(1)Accordingly,population-based recommendations for exercise,and more recently public health guidelines for PA,have been developed and released by authoritative groups for many decades.^(2)Such guidelines emerged with leadership from the exercise physiology discipline and were rooted in,and loyal to,the importance of moderate-to-vigorous intensity PA(MVPA)or exercise.
文摘Introduction:Parkinson’s disease(PD)is the most common neurodegenerative movement disorder.The pathological hallmark is the progressive loss of dopaminergic neurons of the substantia nigra pars compacta,which is accompanied by widespread alterations in the structu re and function of distributed brain networks.Togethe r,these processes cause a variety of motor symptoms such as bradykinesia,rigidity,tremor,gait disorders,or difficulties in fine motor control(Bange et al.,2022).