This study investagated the data of the prevalence of intestinal parasites of human from September 2007 to July 2008 using faecal samples which were picked from refuse dump sites. A total of 2,050 stool samples picked...This study investagated the data of the prevalence of intestinal parasites of human from September 2007 to July 2008 using faecal samples which were picked from refuse dump sites. A total of 2,050 stool samples picked and examined from five selected popular refuse dump sites in Ado-Ekiti. And Entamoeba histolytica, Giardia lamblia and Balantidium coli were mostly identified. The analysis of the infection shows that E. histolytica has a percentage prevalence of 65.5%, followed by G. lamblia with 42.5% and B. coli having 1.9%. Multiple infections of these parasites were also prevalent. There was a positive correlation (r=0.995, P〈0.05) between percentage prevalence of infection and home surroundings, waste, sewage disposal facilities and habits. Also, there was a significant difference (t=1 1.06, P〈0.05) in the prevalence of infections between location A and B. Probable ways of eliminating/controlling the disease are also highlighted.展开更多
The sustainability of ecosystem restoration of refuse dumps in open-pit coal mines depends on plant species selection, their configuration, and the optimal usage of water resources. This study is based on field experi...The sustainability of ecosystem restoration of refuse dumps in open-pit coal mines depends on plant species selection, their configuration, and the optimal usage of water resources. This study is based on field experiments in the northern refuse dump of the Heidaigou open-pit coal mine in Inner Mongolia of China established in 1995. Eight plant configurations, including trees, shrubs, grasses, and their combinations, as well as the adjacent community of natural vegetation, were selected. The succession of the revegetated plants, soil water storage, the spatiotemporal distribution of plant water deficits degree and its compensation degree were also studied. Results indicated that the vegetation cover (shrubs and herbaceous cover), richness, abundance, soil nutrients (soil organic matter, N and P), and biological soil crust coverage on the soil surface are significantly influenced by the vegetation configurations. The average soil water storage values in the shrub + grass and grass communities throughout the growing season are 208.69 mm and 206.55 mm, which are the closest to that of in the natural vegetation community (215.87 mm). Plant water deficits degree in the grass and shrub + grass communities were the lowest, but the degrees of water deficit compensation in these configuration were larger than those of the other vegetation configurations. Differences in plant water deficit degree and water compensation among the different config- urations were significant (P 〈0.05). Plant water deficit degrees were predominantly minimal on the surface, increased with increasing soil depth, and remained stable at 80 cm soil depth. The soil moisture compensation in the natural vegetation, shrub + grass, and grass communities changed at 10%, while that in other vegetation communities changed between 20% and 40%. Overall, we conclude that the shrub + grass and grass configuration modes are the optimal vegetation restoration models in terms of ecohydrology for future ecological engineering projects.展开更多
A self-heating intensity index(SHII)based on the highest(pixel max.)and lowest(pixel min.)values taken from satellite thermal maps of burning coal waste dumps are proposed.The index enables the classification of such ...A self-heating intensity index(SHII)based on the highest(pixel max.)and lowest(pixel min.)values taken from satellite thermal maps of burning coal waste dumps are proposed.The index enables the classification of such fires in Ukrainian-and Polish coal waste dumps.Both in Ukraine and in Poland,varying thermal intensities during 1985–2019 are revealed,using the SHII and following thermal intensity threshold values,namely,extreme thermal activity([7),advanced(3–7),moderate(3–1.5),initial(1.5–1),no activity(<1).The SHII shows decreasing thermal activity in the selected Ukrainian coal waste dumps during 2017–2019.It aids in reconstructing the thermal history of the dumps.Analysis of satellite images revealed a large number of burning coal waste dumps in the Donetsk Coal Basin(Ukraine)with high thermal activity.Such burning likely reflects large amounts of organic matter and sulphides in the dumped material subjected to self-heating and self-burning processes,lack of compaction of the coal waste and/or high methane contents.Comparison of SHII values calculated from satellite-and drone thermal-camera images were compared to show that SHII from drone thermal images have much higher values than those from satellite images;the former have better resolution.Thus,SHII from Landsat-and drone images should be used separately in dump heating studies.展开更多
Wastewater treatment plants and solid dump sites act as potential reservoirs of highly resistant bacterial strains. This study presents information on the patterns of antimicrobial resistance among pathogenic bacteria...Wastewater treatment plants and solid dump sites act as potential reservoirs of highly resistant bacterial strains. This study presents information on the patterns of antimicrobial resistance among pathogenic bacteria in the sewage treatment plants and solid dump site in Nairobi County, Kenya. We employed standard microbiological methods to isolate and identify bacteria from these selected sites. Members of Escherichia, Klebsiella, Serratia, Shigella, Pseudomonas, Citrobacter spp, Enterobacter, Salmonella, Staphylococcus, Bacillus, Yersinia, Vibro cholera, Providencia, Morganella and Proteus spp were isolated. Escherichia and Klebsiella recorded the highest occurrence at 13.9% and 10.3% in wastewater. Shigella, Serratia Citrobacterfreundii, Pseudomonas, Staphylococcus, Escherichia and Klebsiella recorded the highest level of occurrence at 15.1%, 14.1%, 12%, 11%, 10.4%, 10.3%, and 8.3% in dumpsite respectively. Drug sensitivity using the Disc diffusion method showed that Ampicillin, Ceftazidime, Cefotaxime, Amoxicillin, and Cefepime had the highest levels of inactivity at (68.5%, 89.5%), (64.2%, 87%), (54.5%, 80.2%), (52%, 74%) and (49.1%, 72.4%) respectively while Levofloxacin and Gentamicin showed the smallest level of antibiotic resistance at (4.8%, 4.7%) and (4.2%, 2.6%) in both sites. Members of Escherichia, Klebsiella, Proteus vulgaris, Salmonella, Pseudomonas, Shigella and Serratia showed the highest level of ESBLs production at 28.9%, 18.4%, 15.8%, 10.5%, 7.9%, 7.9%, 7.9% and 7.9% in the wastewater whereas Shigella, Escherichia, Serratia, Pseudomonas, Klebsiella, and Proteus vulgaris showed the highest level ESBLs production at 45.5%, 10.9%, 9.1%, 9.1%, 7.3% and 7.3% from the dump site. All the antibiotics tested except for Gentamicin, Chloramphenicol and Ciprofloxacin differed significantly in terms of resistance levels (p < 0.05). The study concluded that, wastewater treatment plant and dump sites bear heavy burdens of potentially virulent resistant bacterial strains which may constitute major public health hazards to scavengers and those living near these sites. There is need therefore to educate people on the use of appropriate protective materials and the settlement patterns of individuals and communities near these sites.展开更多
According to the degree of land cultivation based on the service life of dump, the soil quality and the natural circumstance, the land recultivation region may be diuided into three areas of high-technical agriculture...According to the degree of land cultivation based on the service life of dump, the soil quality and the natural circumstance, the land recultivation region may be diuided into three areas of high-technical agriculture, forestry and livestock farming. After land rebuilding, the vegetation will achieve the standard of farming and forestry to form an integrated harness area of agriculture, forestry and livestock farming. The purposes are to provide a magnitude of employment and enhance the land utilizing capability, as well as to generalize in other minefields in which the social benefit will be significant. Moreover, the recultivation will bring back a green urban to Fuxin City and eliminate a serious source of pollution, therefore the live quality of citizen will be improved.展开更多
Legacy mine shafts and waste dumps in the Witwatersrand continue to create social and environmental challenges for communities, even in areas where gold mining ceased over 100 years ago. The slow pace of eradication o...Legacy mine shafts and waste dumps in the Witwatersrand continue to create social and environmental challenges for communities, even in areas where gold mining ceased over 100 years ago. The slow pace of eradication of these gold mine shafts and waste dumps (or lack thereof) results in conflict between the communities and authorities, particularly the Department of Mineral Resources and Energy (DMRE) as the relevant authority in the field of environmental management in mining. This paper examines, through a literature review, the past and present legislative framework that resulted in legacy mine shafts and dumps and how communities find themselves living next to these mine sites, which results in social and environmental problems. The paper further explores the governments, particularly the DMRE, proposed initiatives to empower those who intend to extract value from the abandoned mines while curbing the scourge of crime in affected communities.展开更多
Reclamations of dumps in the Most Basin that is located in the North Bohemia consist of restoration of extremely unfavourable properties of rocks that are poured down onto the dump body. These rocks come from the surf...Reclamations of dumps in the Most Basin that is located in the North Bohemia consist of restoration of extremely unfavourable properties of rocks that are poured down onto the dump body. These rocks come from the surface layer and the layer where coal bed is present. Sands, clay sands and kaolin (illitic clays) are the main components that occur in the material. Other components are predominantly organic (coal) mass, siderite and pyrite. This report briefly summarizes the history and present of ore, non-metallic and coal mining in the region and addresses in detail the issue of moderating the consequences of mining, which is one of the principal activities of the Research Institute for Brown Coal, j.s.c. in Most. The concept of landscape reclamation in the largest dumps after mining ends, the technical reclamation methodology and the well considered use of fertilizable soil are main results presented in this article.展开更多
Safety berms(also called safety bunds or windrows),widely employed in surface mining and quarry operations,are typically designed based on rules of thumb.Despite having been used by the industry for more than half a c...Safety berms(also called safety bunds or windrows),widely employed in surface mining and quarry operations,are typically designed based on rules of thumb.Despite having been used by the industry for more than half a century and accidents happening regularly,their behaviour is still poorly understood.This paper challenges existing practices through a comprehensive investigation combining full-scale experiments and advanced numerical modelling.Focusing on a Volvo A45G articulated dump truck(ADT)and a CAT 773B rigid dump truck(RDT),collision scenarios under various approach conditions and different safety berm geometries and materials are rigorously examined.The calibrated numerical model is used to assess the energy absorption capacity of safety berms with different geometry and to predict a critical velocity for a specific scenario.Back analysis of an actual fatal accident indicated that an ADT adhering to the speed limit could not be stopped by the safety berm designed under current guidelines.The study highlights the importance of considering the entire geometry and the mass and volume of the material used to build the safety berm alongside the speed and approach conditions of the machinery.The findings of the study enable operators to set speed limits based on specific berm geometries or adapt safety berm designs to match speed constraints for specific machinery.This will reduce the risk of fatal accidents and improve haul road safety.展开更多
Minor errors in the spoil deposition process,such as placing stronger materials with higher shear strength over weaker ones,can lead to potential dump failure.Irregular deposition and inadequate compaction complicate ...Minor errors in the spoil deposition process,such as placing stronger materials with higher shear strength over weaker ones,can lead to potential dump failure.Irregular deposition and inadequate compaction complicate coal spoil behaviour,neces-sitating a robust methodology for temporal monitoring.This study explores using unmanned aerial vehicles(UAV)equipped with red-green-blue(RGB)sensors for efficient data acquisition.Despite their prevalence,raw UAV data exhibit temporal inconsistency,hindering accurate assessments of changes over time which could be attributed to radiometric errors.To this end,the study introduces an empirical line calibration with invariant targets(ELC-IT),for precise calibration across diverse scenes,particularly in the context of UAV imagery used to monitor the evolving nature of spoil dumps.To evaluate the effec-tiveness of this calibration approach,accuracy assessment of an object-based classification is conducted on both calibrated and uncalibrated data.This classification involves several steps:performing segmentation,carrying out feature extraction,and integrating the extracted features and ground truth labels collected over the time period of UAV image capture into machine learning pipelines.Calibrated RGB data exhibit a substantial performance advantage,achieving a 90.7%overall accuracy for spoil pile classification using ensemble(subspace discriminant),representing a noteworthy 7%improvement compared to classifying uncalibrated data.The study highlights the critical role of data calibration in optimising UAV effectiveness for spatio-temporal mine dump monitoring.These findings play a crucial role in informing and refining sustainable management practices within the domain of mine waste management.展开更多
High-steep waste dumps in open-pit mines frequently demonstrate complex particle-size distributions and fractal characteristics along their slopes,which have a significant impact on slope stability.This study takes th...High-steep waste dumps in open-pit mines frequently demonstrate complex particle-size distributions and fractal characteristics along their slopes,which have a significant impact on slope stability.This study takes the Dasuji South waste dump in Inner Mongolia as a case to quantify the fractal dimensions of soil-rock mixtures at various slope heights,and to clarify how these fractal properties govern shear strength and deformation behavior under overlying stress,thereby affecting the overall stability of the waste dump slope.Field sampling and laboratory tests were conducted to determine the particle-size composition and fractal dimensions while direct shear tests were conducted and revealed that lower fractal dimensions indicating coarser particle assemblages significantly enhance shear resistance.Complementary PFC_(2)D discrete element simulations demonstrate that slopes composed of lower-fractaldimension materials deform less and contain localized deformation zones,whereas higher-fractal-dimension slopes experience more extensive displacement and a heightened risk of landslides.These findings refine our understanding of the relationship between fractal grain-size distribution and slope stability,providing a robust theoretical basis for improved stability assessment and optimized support strategies in deep open-pit mining waste dumps,and ultimately aiding in more effective disaster prevention within geotechnical engineering.展开更多
BACKGROUND Endoscopic bariatric therapies(EBT)have been developed as an adjunctive therapy to treat persistent obesity and recurrent weight gain and dumping symptoms after metabolic and bariatric surgery(MBS).While th...BACKGROUND Endoscopic bariatric therapies(EBT)have been developed as an adjunctive therapy to treat persistent obesity and recurrent weight gain and dumping symptoms after metabolic and bariatric surgery(MBS).While the efficacy of revisional EBTs has been documented,no studies to date have examined how these procedures impact quality of life(QOL)and internalized weight bias(IWB).AIM To understand how endoscopic revisional therapies impact QOL,IWB,and dumping syndrome.METHODS Analysis included 19 participants treated for post-MBS recurrent weight gain and/or dumping syndrome.The short-form 36 survey,weight bias internalization scale,and the Sigstad scoring system were used to measure QOL,IWB,and dumping syndrome pre-and≥4 weeks post-EBT.RESULTS At 6-months,total body weight loss was 8.6%±7.15%(n=16),at 12-months was 13.4%±7.46%(n=16).Short-form 36 scores for all 8 scales significantly increased from pre-to post-procedure with the greatest improvement in the scales related to emotional(mean improvement=59.6,P<0.05)and physical health(mean improvement=31.1,P<0.05).Both total Sigstad score(mean difference=4.947,P<0.05)and total weight bias internalization score(mean difference=0.761,P<0.05)significantly decreased from pre-to post-procedure.CONCLUSION Findings suggest that revisional EBT may improve post-MBS QOL across a broad spectrum of outcomes beyond optimizing body weight.As early EBT results indicate positive mental and physical health outcomes,further research is needed to evaluate the relationship between these improvements,body weight and interdisciplinary post-MBS care.展开更多
Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump mate...Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump materials is imperative for an adequate evaluation of the seismic stability of OB dump slopes.In this study,pseudo-static seismic stability analyses are carried out for an OB dump slope by considering the material parameters obtained from an insitu field investigation.Spatial heterogeneity is simulated through use of the random finite element method(RFEM)and the random limit equilibrium method(RLEM)and a comparative study is presented.Combinations of horizontal and vertical spatial correlation lengths were considered for simulating isotropic and anisotropic random fields within the OB dump slope.Seismic performances of the slope have been reported through the probability of failure and reliability index.It was observed that the RLEM approach overestimates failure probability(P_(f))by considering seismic stability with spatial heterogeneity.The P_(f)was observed to increase with an increase in the coefficient of variation of friction angle of the dump materials.Further,it was inferred that the RLEM approach may not be adequately applicable for assessing the seismic stability of an OB dump slope for a horizontal seismic coefficient that is more than or equal to 0.1.展开更多
With the rapid growth of China's economic strength,the demand and market share are also constantly increasing.The number ofcars is rapidly increasing,and a large amount of fuel is consumed as a result.The massive ...With the rapid growth of China's economic strength,the demand and market share are also constantly increasing.The number ofcars is rapidly increasing,and a large amount of fuel is consumed as a result.The massive release of vehicle exhaust seriously damages the natural environment,and the environmental crisis is becoming increasingly serious.This article follows the principles of improving fuel efficiency,reducing emissions,andenhancing vehicle performance.Using NX 12.0 software,a three-dimensional model of a certain type of dump truck frame is constructed based on actual parameters.ANSYS Workbench is used to simplify the geometric model,mesh division,and material definition,and a finite element model is constructed.Obtain the structural performance and natural vibration characteristics of the original chassis under four typical working conditions:bending,torsion,lifting,and unloading,through static analysis and modal analysis.On this basis,the dimensions of the components that bear less load on the original frame were optimized,and the topology of the second crossbeam and rear end corner of the subframe that bear less load on the original frame was optimized to obtain a new frame.The new frame of the dump truck underwent secondary static analysis and modal analysis,and it was found that the weight of the new frame decreased by 41.03 kg,successfully reducing the weight of the frame by 4.38%,improving the vehicle's handling and stability,and extending its service life.展开更多
Water resources are vital for all living beings and should be managed properly to ensure the safety and well-being of humankind.Surface water bodies are constantly faced with serious contamination risks generated prim...Water resources are vital for all living beings and should be managed properly to ensure the safety and well-being of humankind.Surface water bodies are constantly faced with serious contamination risks generated primarily by human activities and urbanization.The problem of waste littering and dumping in developing countries like Nigeria is increasingly affecting environmental resources such as air and water.Several studies have revealed alarming levels of heavy metals that exceed the World Health Organization(WHO)standards.Plastic waste represents a substantial portion of litter,affecting water quality.Pollution results in the depletion of aquatic ecosystems and an increase in water-related diseases.This review aims to assess the impact of waste littering and dumping on surface water quality in Nigeria.In this review,the findings of various studies on surface water bodies in Nigeria,particularly those under the influence of urbanization and waste disposal,were compiled.This review compared numerous physical and chemical parameters like pH,dissolved oxygen,and heavy metals,and microbiological properties such as total coliforms.The water quality index(WQI)was also computed in these studies to ascertain the suitability of the water samples for human consumption.Review results showed that numerous water bodies in Nigeria have significantly diverse water quality levels,with some samples meeting or exceeding the WHO guidelines for microbiological,chemical,and physical characteristics.Notably,levels of heavy metals,turbidity,and pH frequently exceeded permissible limits,pointing to contamination from agricultural and industrial sources.The WQI results for multiple locations revealed that the majority of surface water sources were classified as“bad”to“very bad”,meaning they were unfit for human consumption.The results emphasized the critical need for immediate action to prevent further harm and deterioration of surface water bodies in Nigeria.Recommendations include strengthening waste management policies,promoting recycling initiatives,fostering collaborations among stakeholders,developing littering penalties and enforcing fines to curb the challenge,and raising educational awareness from the primary level.This review emphasizes the need for proactive measures to protect the environment and surface water quality in Nigeria.展开更多
Open pit mining operations generate significant spoil dumps that need to be characterised for stability to identify potentially unstable slopes.However,the current subjective practice for spoil characterisation often ...Open pit mining operations generate significant spoil dumps that need to be characterised for stability to identify potentially unstable slopes.However,the current subjective practice for spoil characterisation often involves tedious and risky field work.To this end,this study demonstrated the use of periodically acquired unmanned aerial vehicle(UAV)-based images over a coal mine spoil dump in New South Wales,Australia.A granular approach that captures the variability of each truck offload pile on a dump was adopted through morphology-based segmentation and ensemble algorithm-based classification which consolidates predictions from multiple classifiers.Overall accuracy of over 90% in the material characterisation based on the classification framework was achieved.The two-dimensional classification outcome was then transformed into three-dimensional(3D)block models using a point-based interpolation approach for stability analysis.The factor of safety derived from the granular approach offered improved assessment of failure risk compared to the conventional approaches,which treat the entire dump as a uniform category.This rapid classification and assessment method proposed in this study will help reduce the uncertainty associated with the variability of spoil dumps in slope stability assessments,thereby enhancing the safety and efficiency of mining operations.展开更多
文摘This study investagated the data of the prevalence of intestinal parasites of human from September 2007 to July 2008 using faecal samples which were picked from refuse dump sites. A total of 2,050 stool samples picked and examined from five selected popular refuse dump sites in Ado-Ekiti. And Entamoeba histolytica, Giardia lamblia and Balantidium coli were mostly identified. The analysis of the infection shows that E. histolytica has a percentage prevalence of 65.5%, followed by G. lamblia with 42.5% and B. coli having 1.9%. Multiple infections of these parasites were also prevalent. There was a positive correlation (r=0.995, P〈0.05) between percentage prevalence of infection and home surroundings, waste, sewage disposal facilities and habits. Also, there was a significant difference (t=1 1.06, P〈0.05) in the prevalence of infections between location A and B. Probable ways of eliminating/controlling the disease are also highlighted.
基金supported by the CAS Action-plan for Western Development(KZCX2-XB3-13-03)Chinese National Natural Scientific Foundation(4120108431170385)
文摘The sustainability of ecosystem restoration of refuse dumps in open-pit coal mines depends on plant species selection, their configuration, and the optimal usage of water resources. This study is based on field experiments in the northern refuse dump of the Heidaigou open-pit coal mine in Inner Mongolia of China established in 1995. Eight plant configurations, including trees, shrubs, grasses, and their combinations, as well as the adjacent community of natural vegetation, were selected. The succession of the revegetated plants, soil water storage, the spatiotemporal distribution of plant water deficits degree and its compensation degree were also studied. Results indicated that the vegetation cover (shrubs and herbaceous cover), richness, abundance, soil nutrients (soil organic matter, N and P), and biological soil crust coverage on the soil surface are significantly influenced by the vegetation configurations. The average soil water storage values in the shrub + grass and grass communities throughout the growing season are 208.69 mm and 206.55 mm, which are the closest to that of in the natural vegetation community (215.87 mm). Plant water deficits degree in the grass and shrub + grass communities were the lowest, but the degrees of water deficit compensation in these configuration were larger than those of the other vegetation configurations. Differences in plant water deficit degree and water compensation among the different config- urations were significant (P 〈0.05). Plant water deficit degrees were predominantly minimal on the surface, increased with increasing soil depth, and remained stable at 80 cm soil depth. The soil moisture compensation in the natural vegetation, shrub + grass, and grass communities changed at 10%, while that in other vegetation communities changed between 20% and 40%. Overall, we conclude that the shrub + grass and grass configuration modes are the optimal vegetation restoration models in terms of ecohydrology for future ecological engineering projects.
文摘A self-heating intensity index(SHII)based on the highest(pixel max.)and lowest(pixel min.)values taken from satellite thermal maps of burning coal waste dumps are proposed.The index enables the classification of such fires in Ukrainian-and Polish coal waste dumps.Both in Ukraine and in Poland,varying thermal intensities during 1985–2019 are revealed,using the SHII and following thermal intensity threshold values,namely,extreme thermal activity([7),advanced(3–7),moderate(3–1.5),initial(1.5–1),no activity(<1).The SHII shows decreasing thermal activity in the selected Ukrainian coal waste dumps during 2017–2019.It aids in reconstructing the thermal history of the dumps.Analysis of satellite images revealed a large number of burning coal waste dumps in the Donetsk Coal Basin(Ukraine)with high thermal activity.Such burning likely reflects large amounts of organic matter and sulphides in the dumped material subjected to self-heating and self-burning processes,lack of compaction of the coal waste and/or high methane contents.Comparison of SHII values calculated from satellite-and drone thermal-camera images were compared to show that SHII from drone thermal images have much higher values than those from satellite images;the former have better resolution.Thus,SHII from Landsat-and drone images should be used separately in dump heating studies.
文摘Wastewater treatment plants and solid dump sites act as potential reservoirs of highly resistant bacterial strains. This study presents information on the patterns of antimicrobial resistance among pathogenic bacteria in the sewage treatment plants and solid dump site in Nairobi County, Kenya. We employed standard microbiological methods to isolate and identify bacteria from these selected sites. Members of Escherichia, Klebsiella, Serratia, Shigella, Pseudomonas, Citrobacter spp, Enterobacter, Salmonella, Staphylococcus, Bacillus, Yersinia, Vibro cholera, Providencia, Morganella and Proteus spp were isolated. Escherichia and Klebsiella recorded the highest occurrence at 13.9% and 10.3% in wastewater. Shigella, Serratia Citrobacterfreundii, Pseudomonas, Staphylococcus, Escherichia and Klebsiella recorded the highest level of occurrence at 15.1%, 14.1%, 12%, 11%, 10.4%, 10.3%, and 8.3% in dumpsite respectively. Drug sensitivity using the Disc diffusion method showed that Ampicillin, Ceftazidime, Cefotaxime, Amoxicillin, and Cefepime had the highest levels of inactivity at (68.5%, 89.5%), (64.2%, 87%), (54.5%, 80.2%), (52%, 74%) and (49.1%, 72.4%) respectively while Levofloxacin and Gentamicin showed the smallest level of antibiotic resistance at (4.8%, 4.7%) and (4.2%, 2.6%) in both sites. Members of Escherichia, Klebsiella, Proteus vulgaris, Salmonella, Pseudomonas, Shigella and Serratia showed the highest level of ESBLs production at 28.9%, 18.4%, 15.8%, 10.5%, 7.9%, 7.9%, 7.9% and 7.9% in the wastewater whereas Shigella, Escherichia, Serratia, Pseudomonas, Klebsiella, and Proteus vulgaris showed the highest level ESBLs production at 45.5%, 10.9%, 9.1%, 9.1%, 7.3% and 7.3% from the dump site. All the antibiotics tested except for Gentamicin, Chloramphenicol and Ciprofloxacin differed significantly in terms of resistance levels (p < 0.05). The study concluded that, wastewater treatment plant and dump sites bear heavy burdens of potentially virulent resistant bacterial strains which may constitute major public health hazards to scavengers and those living near these sites. There is need therefore to educate people on the use of appropriate protective materials and the settlement patterns of individuals and communities near these sites.
文摘According to the degree of land cultivation based on the service life of dump, the soil quality and the natural circumstance, the land recultivation region may be diuided into three areas of high-technical agriculture, forestry and livestock farming. After land rebuilding, the vegetation will achieve the standard of farming and forestry to form an integrated harness area of agriculture, forestry and livestock farming. The purposes are to provide a magnitude of employment and enhance the land utilizing capability, as well as to generalize in other minefields in which the social benefit will be significant. Moreover, the recultivation will bring back a green urban to Fuxin City and eliminate a serious source of pollution, therefore the live quality of citizen will be improved.
文摘Legacy mine shafts and waste dumps in the Witwatersrand continue to create social and environmental challenges for communities, even in areas where gold mining ceased over 100 years ago. The slow pace of eradication of these gold mine shafts and waste dumps (or lack thereof) results in conflict between the communities and authorities, particularly the Department of Mineral Resources and Energy (DMRE) as the relevant authority in the field of environmental management in mining. This paper examines, through a literature review, the past and present legislative framework that resulted in legacy mine shafts and dumps and how communities find themselves living next to these mine sites, which results in social and environmental problems. The paper further explores the governments, particularly the DMRE, proposed initiatives to empower those who intend to extract value from the abandoned mines while curbing the scourge of crime in affected communities.
基金supported by project QJ1520307 entitled“Sustainable Forms of Management in an Anthropogenically Burdened Region.”financial support from state budget resources through the KUS program,Ministry of Agriculture of the Czech Republic.
文摘Reclamations of dumps in the Most Basin that is located in the North Bohemia consist of restoration of extremely unfavourable properties of rocks that are poured down onto the dump body. These rocks come from the surface layer and the layer where coal bed is present. Sands, clay sands and kaolin (illitic clays) are the main components that occur in the material. Other components are predominantly organic (coal) mass, siderite and pyrite. This report briefly summarizes the history and present of ore, non-metallic and coal mining in the region and addresses in detail the issue of moderating the consequences of mining, which is one of the principal activities of the Research Institute for Brown Coal, j.s.c. in Most. The concept of landscape reclamation in the largest dumps after mining ends, the technical reclamation methodology and the well considered use of fertilizable soil are main results presented in this article.
基金initiated and financially supported by Stevenson Aggregates and Fulton Hogan.
文摘Safety berms(also called safety bunds or windrows),widely employed in surface mining and quarry operations,are typically designed based on rules of thumb.Despite having been used by the industry for more than half a century and accidents happening regularly,their behaviour is still poorly understood.This paper challenges existing practices through a comprehensive investigation combining full-scale experiments and advanced numerical modelling.Focusing on a Volvo A45G articulated dump truck(ADT)and a CAT 773B rigid dump truck(RDT),collision scenarios under various approach conditions and different safety berm geometries and materials are rigorously examined.The calibrated numerical model is used to assess the energy absorption capacity of safety berms with different geometry and to predict a critical velocity for a specific scenario.Back analysis of an actual fatal accident indicated that an ADT adhering to the speed limit could not be stopped by the safety berm designed under current guidelines.The study highlights the importance of considering the entire geometry and the mass and volume of the material used to build the safety berm alongside the speed and approach conditions of the machinery.The findings of the study enable operators to set speed limits based on specific berm geometries or adapt safety berm designs to match speed constraints for specific machinery.This will reduce the risk of fatal accidents and improve haul road safety.
基金supported by the Australian Coal Industry's Research Program(ACARP)(C29048).
文摘Minor errors in the spoil deposition process,such as placing stronger materials with higher shear strength over weaker ones,can lead to potential dump failure.Irregular deposition and inadequate compaction complicate coal spoil behaviour,neces-sitating a robust methodology for temporal monitoring.This study explores using unmanned aerial vehicles(UAV)equipped with red-green-blue(RGB)sensors for efficient data acquisition.Despite their prevalence,raw UAV data exhibit temporal inconsistency,hindering accurate assessments of changes over time which could be attributed to radiometric errors.To this end,the study introduces an empirical line calibration with invariant targets(ELC-IT),for precise calibration across diverse scenes,particularly in the context of UAV imagery used to monitor the evolving nature of spoil dumps.To evaluate the effec-tiveness of this calibration approach,accuracy assessment of an object-based classification is conducted on both calibrated and uncalibrated data.This classification involves several steps:performing segmentation,carrying out feature extraction,and integrating the extracted features and ground truth labels collected over the time period of UAV image capture into machine learning pipelines.Calibrated RGB data exhibit a substantial performance advantage,achieving a 90.7%overall accuracy for spoil pile classification using ensemble(subspace discriminant),representing a noteworthy 7%improvement compared to classifying uncalibrated data.The study highlights the critical role of data calibration in optimising UAV effectiveness for spatio-temporal mine dump monitoring.These findings play a crucial role in informing and refining sustainable management practices within the domain of mine waste management.
基金supported by the National Key Research and Development Program of China(2024YFC2909500)State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering(SDGZ2505)National Natural Science Foundation of China(42377148)。
文摘High-steep waste dumps in open-pit mines frequently demonstrate complex particle-size distributions and fractal characteristics along their slopes,which have a significant impact on slope stability.This study takes the Dasuji South waste dump in Inner Mongolia as a case to quantify the fractal dimensions of soil-rock mixtures at various slope heights,and to clarify how these fractal properties govern shear strength and deformation behavior under overlying stress,thereby affecting the overall stability of the waste dump slope.Field sampling and laboratory tests were conducted to determine the particle-size composition and fractal dimensions while direct shear tests were conducted and revealed that lower fractal dimensions indicating coarser particle assemblages significantly enhance shear resistance.Complementary PFC_(2)D discrete element simulations demonstrate that slopes composed of lower-fractaldimension materials deform less and contain localized deformation zones,whereas higher-fractal-dimension slopes experience more extensive displacement and a heightened risk of landslides.These findings refine our understanding of the relationship between fractal grain-size distribution and slope stability,providing a robust theoretical basis for improved stability assessment and optimized support strategies in deep open-pit mining waste dumps,and ultimately aiding in more effective disaster prevention within geotechnical engineering.
文摘BACKGROUND Endoscopic bariatric therapies(EBT)have been developed as an adjunctive therapy to treat persistent obesity and recurrent weight gain and dumping symptoms after metabolic and bariatric surgery(MBS).While the efficacy of revisional EBTs has been documented,no studies to date have examined how these procedures impact quality of life(QOL)and internalized weight bias(IWB).AIM To understand how endoscopic revisional therapies impact QOL,IWB,and dumping syndrome.METHODS Analysis included 19 participants treated for post-MBS recurrent weight gain and/or dumping syndrome.The short-form 36 survey,weight bias internalization scale,and the Sigstad scoring system were used to measure QOL,IWB,and dumping syndrome pre-and≥4 weeks post-EBT.RESULTS At 6-months,total body weight loss was 8.6%±7.15%(n=16),at 12-months was 13.4%±7.46%(n=16).Short-form 36 scores for all 8 scales significantly increased from pre-to post-procedure with the greatest improvement in the scales related to emotional(mean improvement=59.6,P<0.05)and physical health(mean improvement=31.1,P<0.05).Both total Sigstad score(mean difference=4.947,P<0.05)and total weight bias internalization score(mean difference=0.761,P<0.05)significantly decreased from pre-to post-procedure.CONCLUSION Findings suggest that revisional EBT may improve post-MBS QOL across a broad spectrum of outcomes beyond optimizing body weight.As early EBT results indicate positive mental and physical health outcomes,further research is needed to evaluate the relationship between these improvements,body weight and interdisciplinary post-MBS care.
基金the financial support provided by MHRD,Govt.of IndiaCoal India Limited for providing financial assistance for the research(Project No.CIL/R&D/01/73/2021)the partial financial support provided by the Ministry of Education,Government of India,under SPARC project(Project No.P1207)。
文摘Sudden and unforeseen seismic failures of coal mine overburden(OB)dump slopes interrupt mining operations,cause loss of lives and delay the production of coal.Consideration of the spatial heterogeneity of OB dump materials is imperative for an adequate evaluation of the seismic stability of OB dump slopes.In this study,pseudo-static seismic stability analyses are carried out for an OB dump slope by considering the material parameters obtained from an insitu field investigation.Spatial heterogeneity is simulated through use of the random finite element method(RFEM)and the random limit equilibrium method(RLEM)and a comparative study is presented.Combinations of horizontal and vertical spatial correlation lengths were considered for simulating isotropic and anisotropic random fields within the OB dump slope.Seismic performances of the slope have been reported through the probability of failure and reliability index.It was observed that the RLEM approach overestimates failure probability(P_(f))by considering seismic stability with spatial heterogeneity.The P_(f)was observed to increase with an increase in the coefficient of variation of friction angle of the dump materials.Further,it was inferred that the RLEM approach may not be adequately applicable for assessing the seismic stability of an OB dump slope for a horizontal seismic coefficient that is more than or equal to 0.1.
文摘With the rapid growth of China's economic strength,the demand and market share are also constantly increasing.The number ofcars is rapidly increasing,and a large amount of fuel is consumed as a result.The massive release of vehicle exhaust seriously damages the natural environment,and the environmental crisis is becoming increasingly serious.This article follows the principles of improving fuel efficiency,reducing emissions,andenhancing vehicle performance.Using NX 12.0 software,a three-dimensional model of a certain type of dump truck frame is constructed based on actual parameters.ANSYS Workbench is used to simplify the geometric model,mesh division,and material definition,and a finite element model is constructed.Obtain the structural performance and natural vibration characteristics of the original chassis under four typical working conditions:bending,torsion,lifting,and unloading,through static analysis and modal analysis.On this basis,the dimensions of the components that bear less load on the original frame were optimized,and the topology of the second crossbeam and rear end corner of the subframe that bear less load on the original frame was optimized to obtain a new frame.The new frame of the dump truck underwent secondary static analysis and modal analysis,and it was found that the weight of the new frame decreased by 41.03 kg,successfully reducing the weight of the frame by 4.38%,improving the vehicle's handling and stability,and extending its service life.
基金support received by the University of South Africa for a conducive research environment。
文摘Water resources are vital for all living beings and should be managed properly to ensure the safety and well-being of humankind.Surface water bodies are constantly faced with serious contamination risks generated primarily by human activities and urbanization.The problem of waste littering and dumping in developing countries like Nigeria is increasingly affecting environmental resources such as air and water.Several studies have revealed alarming levels of heavy metals that exceed the World Health Organization(WHO)standards.Plastic waste represents a substantial portion of litter,affecting water quality.Pollution results in the depletion of aquatic ecosystems and an increase in water-related diseases.This review aims to assess the impact of waste littering and dumping on surface water quality in Nigeria.In this review,the findings of various studies on surface water bodies in Nigeria,particularly those under the influence of urbanization and waste disposal,were compiled.This review compared numerous physical and chemical parameters like pH,dissolved oxygen,and heavy metals,and microbiological properties such as total coliforms.The water quality index(WQI)was also computed in these studies to ascertain the suitability of the water samples for human consumption.Review results showed that numerous water bodies in Nigeria have significantly diverse water quality levels,with some samples meeting or exceeding the WHO guidelines for microbiological,chemical,and physical characteristics.Notably,levels of heavy metals,turbidity,and pH frequently exceeded permissible limits,pointing to contamination from agricultural and industrial sources.The WQI results for multiple locations revealed that the majority of surface water sources were classified as“bad”to“very bad”,meaning they were unfit for human consumption.The results emphasized the critical need for immediate action to prevent further harm and deterioration of surface water bodies in Nigeria.Recommendations include strengthening waste management policies,promoting recycling initiatives,fostering collaborations among stakeholders,developing littering penalties and enforcing fines to curb the challenge,and raising educational awareness from the primary level.This review emphasizes the need for proactive measures to protect the environment and surface water quality in Nigeria.
基金supported by the Australian coal industry's research(Grant No.C29048).
文摘Open pit mining operations generate significant spoil dumps that need to be characterised for stability to identify potentially unstable slopes.However,the current subjective practice for spoil characterisation often involves tedious and risky field work.To this end,this study demonstrated the use of periodically acquired unmanned aerial vehicle(UAV)-based images over a coal mine spoil dump in New South Wales,Australia.A granular approach that captures the variability of each truck offload pile on a dump was adopted through morphology-based segmentation and ensemble algorithm-based classification which consolidates predictions from multiple classifiers.Overall accuracy of over 90% in the material characterisation based on the classification framework was achieved.The two-dimensional classification outcome was then transformed into three-dimensional(3D)block models using a point-based interpolation approach for stability analysis.The factor of safety derived from the granular approach offered improved assessment of failure risk compared to the conventional approaches,which treat the entire dump as a uniform category.This rapid classification and assessment method proposed in this study will help reduce the uncertainty associated with the variability of spoil dumps in slope stability assessments,thereby enhancing the safety and efficiency of mining operations.