Objective To investigate the stress distribution of the femur after cemented prosthetic replacement in aged patients with comminuted intertrochanteric fracture and to analyze the difference of stress distribution betw...Objective To investigate the stress distribution of the femur after cemented prosthetic replacement in aged patients with comminuted intertrochanteric fracture and to analyze the difference of stress distribution between cemented long展开更多
Background Although the use of an intramedullary fibular allograft together with locking plate fixation can provide additional medial support and prevent varus malalignment in displaced proximal humeral fractures with...Background Although the use of an intramedullary fibular allograft together with locking plate fixation can provide additional medial support and prevent varus malalignment in displaced proximal humeral fractures with promising results,the fibular autograft donor site often sustains significant trauma and cannot restore the articular surface of comminuted fractures.The aim of this study was to evaluate the clinical and radiographic outcomes of a locking plate and crest bone autologous graft for treating proximal humerus comminuted fractures.Methods We assessed the functional outcomes and complication rates in 40 patients with proximal humerus comminuted fractures.Eighteen patients were treated with a locking plate and an autologous crest bone graft (experimental group),and 22 were treated with only the locking plate and no bone graft (control group).Postoperative assessments included radiographic imaging,range of motion analysis,pain level based on the visual analogue scale (VAS),and the SF-36 (Short Form (36) Health Survey),as well as whether patients could retum to their previous occupation.Results All fractures healed both clinically and radiologically in the experimental group.There was no more than 2 mm collapse of the humeral head,and no osteonecrosis or screw penetration of the articular surface.In contrast,two patients had a nonunion in the control group,and they eventually accepted total shoulder replacements.The average time from surgery to radiographic union was significantly shorter in the experimental group ((4.66±1.63) months) compared with the control group ((5.98±1.57) months) (P <0.05).For the experimental versus controls groups,the mean shoulder active flexion (148.00±18.59 vs.121.73±17.20) degrees,extension (49.00±2.22 vs.42.06±2.06) degrees,internal rotation (45.00±5.61 vs.35.00±3.55)degrees,external rotation (64.00±9.17 vs.52.14±5.73)degrees,and abduction (138.00±28.78 vs.105.95±15.66) degrees were all significantly higher (all P <0.001).The median SF-36 in the experimental group ((88.00±5.71) points) was significantly higher than that of the control group ((69.45±9.45) points; P <0.001).The median VAS pain level (mean rank,10.50) in the experimental group was lower than that (mean rank,47.19) of the control group (P <0.001).All but one patient (17 of 18,94.4%) in the experimental group returned to their previous activities or occupations,and that one patient changed to a different occupation because of slight restrictions to activities.On the other hand,four patients could not return to their previous activities or occupations in the control group.Conclusion Locking plate fixation combined with an iliac crest bone graft is an effective technique for treating proximal humerus comminuted fractures.展开更多
Bone graft may be needed to fill bone defect in elderly patients with a metaphyseal comminuted distal radius fracture. In this retrospective, nonrandomized, single-surgeon study, we evaluated the clinical and radiolog...Bone graft may be needed to fill bone defect in elderly patients with a metaphyseal comminuted distal radius fracture. In this retrospective, nonrandomized, single-surgeon study, we evaluated the clinical and radiologic outcomes of using both dorsal locking plates with or without augmentation with mineralized collagen (MC) bone graft for elderly patients with dorsally metaphyseal comminuted radius fractures. Patients in group 1 (n = 12) were treated with dorsal locking plates with MC bone graft application into the metaphyseal bone defect, and those in group 2 (n - 12) only with dorsal locking plates. Clinical and radiologic parameters were determined at three and 12 months after surgery. At final follow-up, no significant difference was noted between the 2 groups in terms of palmar tilt and radial inclination (p - 0.80); however, ulnar variance increased significantly in the group 2 treated with dorsal locking plates without augmentation (p〈0.05). Functionally, there was no significant difference between the groups. Our preliminary study suggests that combination of MC as bone-graft substitutes and dorsal locking plates may be a usefully alternative for elderly patients with metaphyseal comminuted distal radius fracture.展开更多
Purpose:Comminuted intraarticular distal radial fractures are difficult to treat conservatively and require operative treatment.This study compared the functional outcomes between variable angle volar plating and exte...Purpose:Comminuted intraarticular distal radial fractures are difficult to treat conservatively and require operative treatment.This study compared the functional outcomes between variable angle volar plating and external fixator with K-wire augmentation in open reduction and internal fixation.Methods:A total of 62 adult patients with comminuted intraarticular distal radius fracture were randomized into 2 groups:volar plate group and external fixator group.These patients aged between 18 and 60 years had unilateral fractures,and agreed to be included in the study.Patients with a history of fracture,bilateral fracture,associated other injuries,delayed injury for more than 2 weeks,open fracture,pre-existing arthrosis or disability,psychiatric illness and pathological fracture were excluded.Patients were followed up at 6 weeks,3 months,6 months and 1 year.The assessment of pain,functional activity,range of motion and grip strength was done at each stage of follow-up.The pain and functional activities were assessed by patient rated wrist evaluation(PRWE)score and disabilities of the arm,shoulder and hand(DASH)score.Results:Patients in volar plate group had superior PRWE score and DASH score at each stage of followup.At 1 year follow-up,the mean PRWE score were 7.48 for volar plate group and 7.35 for external fixator group;while the mean DASH score was 4.65 for volar plate group and 5.61 for external fixator group.They had better flexion and extension range of movement.They also had better pronation and supination range of motion at initial follow-up,however the difference get attenuated by 1 year.Volar plate group had significantly better grip strength than external fixator group.Complication rates were higher in external fixation group.Conclusion:Fixation with variable angle volar plate results in early wrist mobilization,better range of movement,less pain and disability and early return of function.展开更多
The objective of this study was to expound a novel surgical management technique assisted by patient-specific implants(PSIs)for comminuted fractures of the zygomaticomaxillary complex(ZMC).The aim of this study was to...The objective of this study was to expound a novel surgical management technique assisted by patient-specific implants(PSIs)for comminuted fractures of the zygomaticomaxillary complex(ZMC).The aim of this study was to explore the feasibility of using PSIs to accurately restore and fix comminuted fractures.A male patient with an old ZMC comminuted fracture was used to describe the workflow,technique,and method.Computerassisted surgical simulation was used to determine the optimal plan for the reduction of bone segments prior to surgery.The PSIs were used to accurately guide the surgeon’s position of the bone segments,as planned,during the operation.Oral panoramic films and cephalometric films were taken immediately at 1,3,6,and 12 months after the operation,while computed tomography images of the whole skull were taken immediately,half a year,and one year after the operation.The patient’s follow-up showed that the zygomatic symmetry recovered well post-surgery and the patient was satisfied with the outcome.This new surgical method greatly improved the facial symmetry of this patient.展开更多
Osteoporosis is characterized by a decrease in bone mass and strength, rendering people prone to osteoporotic fractures caused by low-energy forces. The primary treatment strategy for osteoporotic fractures is surgery...Osteoporosis is characterized by a decrease in bone mass and strength, rendering people prone to osteoporotic fractures caused by low-energy forces. The primary treatment strategy for osteoporotic fractures is surgery;however, the compromised and comminuted bones in osteoporotic fracture sites are not conducive to optimum reduction and rigid fixation. In addition, these patients always exhibit accompanying aging-related disorders, including high inflammatory status, decreased mechanical loading and abnormal skeletal metabolism, which are disadvantages for fracture healing around sites that have undergone orthopedic procedures. Since the incidence of osteoporosis is expected to increase worldwide, orthopedic surgeons should pay more attention to comprehensive strategies for improving the poor prognosis of osteoporotic fractures. Herein, we highlight the molecular basis of osteoimmunology and bone mechanosensation in different healing phases of elderly osteoporotic fractures, guiding perioperative management to alleviate the unfavorable effects of insufficient mechanical loading, high inflammatory levels and pathogen infection. The well-informed pharmacologic and surgical intervention, including treatment with anti-inflammatory drugs and sufficient application of antibiotics, as well as bench-to-bedside strategies for bone augmentation and hardware selection, should be made according to a comprehensive understanding of bone biomechanical properties in addition to the remodeling status of osteoporotic bones, which is necessary for creating proper biological and mechanical environments for bone union and remodeling. Multidisciplinary collaboration will facilitate the improvement of overall osteoporotic care and reduction of secondary fracture incidence.展开更多
The cerclage wire is an important adjuvant in the management of Orthopaedic and trauma cases and is particularly useful in long bone fractures. It is especially useful for addressing the fractures, especially the comm...The cerclage wire is an important adjuvant in the management of Orthopaedic and trauma cases and is particularly useful in long bone fractures. It is especially useful for addressing the fractures, especially the comminuted ones with a butterfly fragment. Orthopaedic cerclage Wiring is used as an adjunct to maintain fracture reduction (either temporarily or permanently), while the bone is primarily stabilised by either a plate intramedullary nail or external fixation frame. Multiple cerclage wires provide adjunctive fixation against compressive shear, bending & rotational forces and have been used in traumatology since many years. The aim of this article is to introduce a new year simple low cost instrument named as “Suyash cerclage wire passer”, with excellent outcomes without any major complications to the Orthopaedic community.展开更多
Blasting of rocks has intrinsic environmental impacts such as ground vibration,which can interfere with the safety of lives and property.Hence,accurate prediction of the environmental impacts of blasting is imperative...Blasting of rocks has intrinsic environmental impacts such as ground vibration,which can interfere with the safety of lives and property.Hence,accurate prediction of the environmental impacts of blasting is imperative as the empirical models are not accurate as evident in the literature.Therefore,there is need to consider some robust predictive models for accurate prediction results.Gene expression programming(GEP),adaptive neuro-fuzzy inference system(ANFIS),and sine cosine algorithm optimized artificial neural network(SCA-ANN)models are proposed for predicting the blast-initiated ground vibration in five granite quarries.The input parameters into the models are the distance from the point of blasting to the point of measurement(D),the weight of charge per delay(W),rock density(q),and the Schmidt rebound hardness(SRH)value while peak particle velocity(PPV)is the targeted output.100 datasets were used in developing the proposed models.The performance of the proposed models was examined using the coefficient of determination(R2)and error analysis.The R2 values obtained for the GEP,ANFIS,and SCA-ANN models are 0.989,0.997,and 0.999,respectively,while their errors are close to zero.The proposed models are compared with an empirical model and are found to outperform the empirical model.展开更多
The latest progress in mineral processing in China is described. It is also pointed out that the existing technology can not meet the needs of economic development. The combined challenges of poor resources, economica...The latest progress in mineral processing in China is described. It is also pointed out that the existing technology can not meet the needs of economic development. The combined challenges of poor resources, economical benefits and environmental pollution issues require further research to upgrade the separation efficiency economically. The methods of mineral processing should play a more important part in waste treatment such as wastewater treatment, the remediation of contaminated soil and the recycling of wastes. Biomineral technology will be utilised in the near future.展开更多
Comminution of coal to ultrafine sizes by high-pressure waterjet provides a novel method for preparation of coal-water fuels for next generation,near-zero emission electric power generation.The particle size distribut...Comminution of coal to ultrafine sizes by high-pressure waterjet provides a novel method for preparation of coal-water fuels for next generation,near-zero emission electric power generation.The particle size distribution(PSD)of ground coal is a key parameter in the preparation of slurries as it determines the settling behavior of the particles and viscosity of the coal-water mixture.There are several methods available for representation and evaluation of particle size analysis data.However,fractal theory provides a means by which the entire PSD of comminuted materials can be quantified by using of a specific and exact value.In this paper,a volume-based fractal model was deduced to characterize the PSD of the coal which is ground in a specially designed comminution cell.During the size reduction process,the inlet pressures up to 276 MPa were used.展开更多
The capabilities and opportunities of the application of automated mineralogy for the characterization of lithium-bearing zinnwaldite-micas are critically assessed. Samples of a crushed greisen-type ore comprising mos...The capabilities and opportunities of the application of automated mineralogy for the characterization of lithium-bearing zinnwaldite-micas are critically assessed. Samples of a crushed greisen-type ore comprising mostly of quartz, topaz and zinnwaldite (Li-rich mica) were exposed to further comminution by cone crusher and high voltage pulse power fragmentation. Product properties were analyzed by using a Mineral Liberation Analyser (MLA) and the obtained mineralogical and mineral processing relevant parameters were carefully evaluated with special focus on the characteristics of zinnwaldite. The results illustrate that both samples contain a significant quantity of very fine particles that are products of comminution. The modal mineralogy in the different sieve fractions is characterized by the accumulation of minerals of low hardness in the finest fraction and the enrichment of topaz, having a high hardness, in the somewhat larger fractions. Based on the results of mineral association data for zinnwaldite, a displacement of the muscovite-quartz ratio, in comparison to the results of modal mineralogy, was observed by indicating good quartz-zinnwaldite boundary breakage and weak muscovite-zinnwaldite breakage. Liberation as well as mineral grade recovery curves indicate that fraction 1000 to +500 μm is most suitable for beneficiation. The results of this study demonstrate that SEM-based image analysis, such as MLA, can effectively be used to investigate and evaluate phyllosilicate minerals in a fast and precise way. It is shown that the results of MLA investigations, such as modal mineralogy, are in good agreement with other analytical methods such as quantitative X-ray powder diffraction.展开更多
Introduction: Proximal femoral nail is a better choice of implant for the treatment of an unstable trochanteric fracture, however it is associated with screw migration and cutout because of greater trochanteric commin...Introduction: Proximal femoral nail is a better choice of implant for the treatment of an unstable trochanteric fracture, however it is associated with screw migration and cutout because of greater trochanteric comminution and coronal split. This study is to evaluate the results of Trochanteric Buttress Plate (TBP) combined with PFN in an unstable IT fractures for buttressing lateral wall and reinforcing fixation. Materials and Methods: We carried out a consecutive study of 32 patients of Unstable intertrochanteric fracture femur with lateral wall comminution. It was studied at Ashwini Sahakari Rugnalaya and Sanshodhan Kendra Solapur India and Government medical college Chandrapur India from April-2015 to December-2017 using innovative Trochanteric buttress plate along with PFN. Eighteen male and fourteen female in the age group of 55 to 80 years were included in the study. There were 26 cases of A3 and six cases of A2 were fixed by PFN combined with trochanteric buttress plate to augment the comminuted lateral wall. Results: The bone healing is observed in all the cases in the mean period of 12.6 weeks. Four patients developed complications, including lateral migration of neck screws (n = 2), superficial infection (n = 2). Patients were followed up for a mean of 10.6 months. At the end of follow-up the Salvati and Wilson hip function was 36 (out of 40) in 87.5% of patients [twenty eight patients]. The clinical, radiological and functional outcomes were found to be satisfactory. Conclusion: The stabilization of lateral trochanteric wall with trochanteric buttress plate restores anatomy, increases the stability of construct and prevents inherent complication of screw migration and cutout.展开更多
The comminution of mica with an abrasive water jet is mainly based on three knids of effects, that is, high-speed collision, cavitating effect and shearing effect. Cavitation abrasive water jet was applied for the com...The comminution of mica with an abrasive water jet is mainly based on three knids of effects, that is, high-speed collision, cavitating effect and shearing effect. Cavitation abrasive water jet was applied for the comminution of mica because cavitation abrasive water jet can make full use of the three effects mentioned above. Besides high speed impacting among particles,cavitation and shearing were also enhanced due to the divergent angle at the outlet of the cavitation nozzle.A JME-200CX transmission electron microscope was used for observing the size distribution of particles.Variance analysis on the experimental results indicates that the effect of cavitation is much more significant than that of collision.The effect of pressure on comminution results becomes less with the decrease of the particle size.展开更多
As one of main raw materials in ceramic industry, chinastone mostly contains minerals such as quartz and sericite. In ultrafine processing of chinastone, the aggregation and adhesion of micropowders caused by surface ...As one of main raw materials in ceramic industry, chinastone mostly contains minerals such as quartz and sericite. In ultrafine processing of chinastone, the aggregation and adhesion of micropowders caused by surface effect lower the efficiency of ultrafine comminution. In this paper, a kind of grinding aid for chinastone delaminating has been developed by the author to change the surfacial electronic property of particles and decrease the viscosity of pulp. Experiments about delaminating-comminuting chinastone ores from Ningcun and Shangzhu (Jiangxi Province, China) reveal that the contents of 2 um grade particles are increased from 23. 0% and 27. 1% to 42. 7% and 45. 3% respectively, the products reach the index at first-class chinastone.展开更多
The ground powders with the same particle size distribution and the same mean particle diameter were prepared by five different types of mills. The flowability index (FI) and the particle shape indices, namely, Wadell...The ground powders with the same particle size distribution and the same mean particle diameter were prepared by five different types of mills. The flowability index (FI) and the particle shape indices, namely, Wadell's working sphericity Ψ W and circularity Ψ C, of five kinds of test powders were measured. The effect of the comminuting mechanisms on the flowability of ground powders was investigated, and the relationship between the flowability of ground powders and the particle shape indices was analyzed. The experimental results show that the ground powders obtained by collision have irregular particle shapes and smooth surfaces, showing a high flowability. On the other hand, though the particle obtained by grinding is close to a spherical particle, but it has a rugged surface, and shows a bad flowability. Furthermore, the flowability index is more correlated with the circularity than the working sphericity is. This means that the surface roughness is more effective in determining the flowability of powders than the roundness is.展开更多
Based upon the aspect of continuous damaging,the process of ore comminution may be des- cribed as the growth and propagation of the microcracks in the ore grains under external load- ing,and a theoretical expression h...Based upon the aspect of continuous damaging,the process of ore comminution may be des- cribed as the growth and propagation of the microcracks in the ore grains under external load- ing,and a theoretical expression has been developed on the relationship between the grain size distribution and the total energy consumption during entire ore comminution process.The en- ergy consumed totally may be considered consisting of two portions,i.e.with fresh crack sur- faces growth and with crack propagation.The proposed expression seems to be an advance over previous conventional ones,especially that from the viewpoint of energy distribution.展开更多
In this paper, the main factors that influence on qualities of kaolin in the area are revealed by studying the properties of coal-series kaolin in Enshi, Hubei (P. R. China), technologies of ferrum and carbon eliminat...In this paper, the main factors that influence on qualities of kaolin in the area are revealed by studying the properties of coal-series kaolin in Enshi, Hubei (P. R. China), technologies of ferrum and carbon elimination for coal-series kaolin are investigated , and ways to fully uti-lize the resource are hopeful to be sought.展开更多
文摘Objective To investigate the stress distribution of the femur after cemented prosthetic replacement in aged patients with comminuted intertrochanteric fracture and to analyze the difference of stress distribution between cemented long
文摘Background Although the use of an intramedullary fibular allograft together with locking plate fixation can provide additional medial support and prevent varus malalignment in displaced proximal humeral fractures with promising results,the fibular autograft donor site often sustains significant trauma and cannot restore the articular surface of comminuted fractures.The aim of this study was to evaluate the clinical and radiographic outcomes of a locking plate and crest bone autologous graft for treating proximal humerus comminuted fractures.Methods We assessed the functional outcomes and complication rates in 40 patients with proximal humerus comminuted fractures.Eighteen patients were treated with a locking plate and an autologous crest bone graft (experimental group),and 22 were treated with only the locking plate and no bone graft (control group).Postoperative assessments included radiographic imaging,range of motion analysis,pain level based on the visual analogue scale (VAS),and the SF-36 (Short Form (36) Health Survey),as well as whether patients could retum to their previous occupation.Results All fractures healed both clinically and radiologically in the experimental group.There was no more than 2 mm collapse of the humeral head,and no osteonecrosis or screw penetration of the articular surface.In contrast,two patients had a nonunion in the control group,and they eventually accepted total shoulder replacements.The average time from surgery to radiographic union was significantly shorter in the experimental group ((4.66±1.63) months) compared with the control group ((5.98±1.57) months) (P <0.05).For the experimental versus controls groups,the mean shoulder active flexion (148.00±18.59 vs.121.73±17.20) degrees,extension (49.00±2.22 vs.42.06±2.06) degrees,internal rotation (45.00±5.61 vs.35.00±3.55)degrees,external rotation (64.00±9.17 vs.52.14±5.73)degrees,and abduction (138.00±28.78 vs.105.95±15.66) degrees were all significantly higher (all P <0.001).The median SF-36 in the experimental group ((88.00±5.71) points) was significantly higher than that of the control group ((69.45±9.45) points; P <0.001).The median VAS pain level (mean rank,10.50) in the experimental group was lower than that (mean rank,47.19) of the control group (P <0.001).All but one patient (17 of 18,94.4%) in the experimental group returned to their previous activities or occupations,and that one patient changed to a different occupation because of slight restrictions to activities.On the other hand,four patients could not return to their previous activities or occupations in the control group.Conclusion Locking plate fixation combined with an iliac crest bone graft is an effective technique for treating proximal humerus comminuted fractures.
文摘Bone graft may be needed to fill bone defect in elderly patients with a metaphyseal comminuted distal radius fracture. In this retrospective, nonrandomized, single-surgeon study, we evaluated the clinical and radiologic outcomes of using both dorsal locking plates with or without augmentation with mineralized collagen (MC) bone graft for elderly patients with dorsally metaphyseal comminuted radius fractures. Patients in group 1 (n = 12) were treated with dorsal locking plates with MC bone graft application into the metaphyseal bone defect, and those in group 2 (n - 12) only with dorsal locking plates. Clinical and radiologic parameters were determined at three and 12 months after surgery. At final follow-up, no significant difference was noted between the 2 groups in terms of palmar tilt and radial inclination (p - 0.80); however, ulnar variance increased significantly in the group 2 treated with dorsal locking plates without augmentation (p〈0.05). Functionally, there was no significant difference between the groups. Our preliminary study suggests that combination of MC as bone-graft substitutes and dorsal locking plates may be a usefully alternative for elderly patients with metaphyseal comminuted distal radius fracture.
文摘Purpose:Comminuted intraarticular distal radial fractures are difficult to treat conservatively and require operative treatment.This study compared the functional outcomes between variable angle volar plating and external fixator with K-wire augmentation in open reduction and internal fixation.Methods:A total of 62 adult patients with comminuted intraarticular distal radius fracture were randomized into 2 groups:volar plate group and external fixator group.These patients aged between 18 and 60 years had unilateral fractures,and agreed to be included in the study.Patients with a history of fracture,bilateral fracture,associated other injuries,delayed injury for more than 2 weeks,open fracture,pre-existing arthrosis or disability,psychiatric illness and pathological fracture were excluded.Patients were followed up at 6 weeks,3 months,6 months and 1 year.The assessment of pain,functional activity,range of motion and grip strength was done at each stage of follow-up.The pain and functional activities were assessed by patient rated wrist evaluation(PRWE)score and disabilities of the arm,shoulder and hand(DASH)score.Results:Patients in volar plate group had superior PRWE score and DASH score at each stage of followup.At 1 year follow-up,the mean PRWE score were 7.48 for volar plate group and 7.35 for external fixator group;while the mean DASH score was 4.65 for volar plate group and 5.61 for external fixator group.They had better flexion and extension range of movement.They also had better pronation and supination range of motion at initial follow-up,however the difference get attenuated by 1 year.Volar plate group had significantly better grip strength than external fixator group.Complication rates were higher in external fixation group.Conclusion:Fixation with variable angle volar plate results in early wrist mobilization,better range of movement,less pain and disability and early return of function.
文摘The objective of this study was to expound a novel surgical management technique assisted by patient-specific implants(PSIs)for comminuted fractures of the zygomaticomaxillary complex(ZMC).The aim of this study was to explore the feasibility of using PSIs to accurately restore and fix comminuted fractures.A male patient with an old ZMC comminuted fracture was used to describe the workflow,technique,and method.Computerassisted surgical simulation was used to determine the optimal plan for the reduction of bone segments prior to surgery.The PSIs were used to accurately guide the surgeon’s position of the bone segments,as planned,during the operation.Oral panoramic films and cephalometric films were taken immediately at 1,3,6,and 12 months after the operation,while computed tomography images of the whole skull were taken immediately,half a year,and one year after the operation.The patient’s follow-up showed that the zygomatic symmetry recovered well post-surgery and the patient was satisfied with the outcome.This new surgical method greatly improved the facial symmetry of this patient.
基金supported by the National Natural Science Foundation of China (81772369, 81401809, 81373150)CAMS Innovation Fund for Medical Sciences (CIFMS, 2017-I2M-3-001)+1 种基金supported by the Beijing Nova program (Z171100001117110)supported by the Beijing Natural Science Foundation (7192127)
文摘Osteoporosis is characterized by a decrease in bone mass and strength, rendering people prone to osteoporotic fractures caused by low-energy forces. The primary treatment strategy for osteoporotic fractures is surgery;however, the compromised and comminuted bones in osteoporotic fracture sites are not conducive to optimum reduction and rigid fixation. In addition, these patients always exhibit accompanying aging-related disorders, including high inflammatory status, decreased mechanical loading and abnormal skeletal metabolism, which are disadvantages for fracture healing around sites that have undergone orthopedic procedures. Since the incidence of osteoporosis is expected to increase worldwide, orthopedic surgeons should pay more attention to comprehensive strategies for improving the poor prognosis of osteoporotic fractures. Herein, we highlight the molecular basis of osteoimmunology and bone mechanosensation in different healing phases of elderly osteoporotic fractures, guiding perioperative management to alleviate the unfavorable effects of insufficient mechanical loading, high inflammatory levels and pathogen infection. The well-informed pharmacologic and surgical intervention, including treatment with anti-inflammatory drugs and sufficient application of antibiotics, as well as bench-to-bedside strategies for bone augmentation and hardware selection, should be made according to a comprehensive understanding of bone biomechanical properties in addition to the remodeling status of osteoporotic bones, which is necessary for creating proper biological and mechanical environments for bone union and remodeling. Multidisciplinary collaboration will facilitate the improvement of overall osteoporotic care and reduction of secondary fracture incidence.
文摘The cerclage wire is an important adjuvant in the management of Orthopaedic and trauma cases and is particularly useful in long bone fractures. It is especially useful for addressing the fractures, especially the comminuted ones with a butterfly fragment. Orthopaedic cerclage Wiring is used as an adjunct to maintain fracture reduction (either temporarily or permanently), while the bone is primarily stabilised by either a plate intramedullary nail or external fixation frame. Multiple cerclage wires provide adjunctive fixation against compressive shear, bending & rotational forces and have been used in traumatology since many years. The aim of this article is to introduce a new year simple low cost instrument named as “Suyash cerclage wire passer”, with excellent outcomes without any major complications to the Orthopaedic community.
基金supported by Korea Research Fellowship Program through the National Research Foundation of Korea(NRF)funded(2019H1D3A1A01102993)。
文摘Blasting of rocks has intrinsic environmental impacts such as ground vibration,which can interfere with the safety of lives and property.Hence,accurate prediction of the environmental impacts of blasting is imperative as the empirical models are not accurate as evident in the literature.Therefore,there is need to consider some robust predictive models for accurate prediction results.Gene expression programming(GEP),adaptive neuro-fuzzy inference system(ANFIS),and sine cosine algorithm optimized artificial neural network(SCA-ANN)models are proposed for predicting the blast-initiated ground vibration in five granite quarries.The input parameters into the models are the distance from the point of blasting to the point of measurement(D),the weight of charge per delay(W),rock density(q),and the Schmidt rebound hardness(SRH)value while peak particle velocity(PPV)is the targeted output.100 datasets were used in developing the proposed models.The performance of the proposed models was examined using the coefficient of determination(R2)and error analysis.The R2 values obtained for the GEP,ANFIS,and SCA-ANN models are 0.989,0.997,and 0.999,respectively,while their errors are close to zero.The proposed models are compared with an empirical model and are found to outperform the empirical model.
文摘The latest progress in mineral processing in China is described. It is also pointed out that the existing technology can not meet the needs of economic development. The combined challenges of poor resources, economical benefits and environmental pollution issues require further research to upgrade the separation efficiency economically. The methods of mineral processing should play a more important part in waste treatment such as wastewater treatment, the remediation of contaminated soil and the recycling of wastes. Biomineral technology will be utilised in the near future.
基金supported by the Missouri University of Science and Technology/Waterjet Laboratory and funded by the China Postdoctoral Science Foundation(Grant No.2014M552555XB)Doctoral Program in Xi’an University of Science and Technology(Grant No.2013QDJ039).
文摘Comminution of coal to ultrafine sizes by high-pressure waterjet provides a novel method for preparation of coal-water fuels for next generation,near-zero emission electric power generation.The particle size distribution(PSD)of ground coal is a key parameter in the preparation of slurries as it determines the settling behavior of the particles and viscosity of the coal-water mixture.There are several methods available for representation and evaluation of particle size analysis data.However,fractal theory provides a means by which the entire PSD of comminuted materials can be quantified by using of a specific and exact value.In this paper,a volume-based fractal model was deduced to characterize the PSD of the coal which is ground in a specially designed comminution cell.During the size reduction process,the inlet pressures up to 276 MPa were used.
文摘The capabilities and opportunities of the application of automated mineralogy for the characterization of lithium-bearing zinnwaldite-micas are critically assessed. Samples of a crushed greisen-type ore comprising mostly of quartz, topaz and zinnwaldite (Li-rich mica) were exposed to further comminution by cone crusher and high voltage pulse power fragmentation. Product properties were analyzed by using a Mineral Liberation Analyser (MLA) and the obtained mineralogical and mineral processing relevant parameters were carefully evaluated with special focus on the characteristics of zinnwaldite. The results illustrate that both samples contain a significant quantity of very fine particles that are products of comminution. The modal mineralogy in the different sieve fractions is characterized by the accumulation of minerals of low hardness in the finest fraction and the enrichment of topaz, having a high hardness, in the somewhat larger fractions. Based on the results of mineral association data for zinnwaldite, a displacement of the muscovite-quartz ratio, in comparison to the results of modal mineralogy, was observed by indicating good quartz-zinnwaldite boundary breakage and weak muscovite-zinnwaldite breakage. Liberation as well as mineral grade recovery curves indicate that fraction 1000 to +500 μm is most suitable for beneficiation. The results of this study demonstrate that SEM-based image analysis, such as MLA, can effectively be used to investigate and evaluate phyllosilicate minerals in a fast and precise way. It is shown that the results of MLA investigations, such as modal mineralogy, are in good agreement with other analytical methods such as quantitative X-ray powder diffraction.
文摘Introduction: Proximal femoral nail is a better choice of implant for the treatment of an unstable trochanteric fracture, however it is associated with screw migration and cutout because of greater trochanteric comminution and coronal split. This study is to evaluate the results of Trochanteric Buttress Plate (TBP) combined with PFN in an unstable IT fractures for buttressing lateral wall and reinforcing fixation. Materials and Methods: We carried out a consecutive study of 32 patients of Unstable intertrochanteric fracture femur with lateral wall comminution. It was studied at Ashwini Sahakari Rugnalaya and Sanshodhan Kendra Solapur India and Government medical college Chandrapur India from April-2015 to December-2017 using innovative Trochanteric buttress plate along with PFN. Eighteen male and fourteen female in the age group of 55 to 80 years were included in the study. There were 26 cases of A3 and six cases of A2 were fixed by PFN combined with trochanteric buttress plate to augment the comminuted lateral wall. Results: The bone healing is observed in all the cases in the mean period of 12.6 weeks. Four patients developed complications, including lateral migration of neck screws (n = 2), superficial infection (n = 2). Patients were followed up for a mean of 10.6 months. At the end of follow-up the Salvati and Wilson hip function was 36 (out of 40) in 87.5% of patients [twenty eight patients]. The clinical, radiological and functional outcomes were found to be satisfactory. Conclusion: The stabilization of lateral trochanteric wall with trochanteric buttress plate restores anatomy, increases the stability of construct and prevents inherent complication of screw migration and cutout.
文摘The comminution of mica with an abrasive water jet is mainly based on three knids of effects, that is, high-speed collision, cavitating effect and shearing effect. Cavitation abrasive water jet was applied for the comminution of mica because cavitation abrasive water jet can make full use of the three effects mentioned above. Besides high speed impacting among particles,cavitation and shearing were also enhanced due to the divergent angle at the outlet of the cavitation nozzle.A JME-200CX transmission electron microscope was used for observing the size distribution of particles.Variance analysis on the experimental results indicates that the effect of cavitation is much more significant than that of collision.The effect of pressure on comminution results becomes less with the decrease of the particle size.
文摘As one of main raw materials in ceramic industry, chinastone mostly contains minerals such as quartz and sericite. In ultrafine processing of chinastone, the aggregation and adhesion of micropowders caused by surface effect lower the efficiency of ultrafine comminution. In this paper, a kind of grinding aid for chinastone delaminating has been developed by the author to change the surfacial electronic property of particles and decrease the viscosity of pulp. Experiments about delaminating-comminuting chinastone ores from Ningcun and Shangzhu (Jiangxi Province, China) reveal that the contents of 2 um grade particles are increased from 23. 0% and 27. 1% to 42. 7% and 45. 3% respectively, the products reach the index at first-class chinastone.
文摘The ground powders with the same particle size distribution and the same mean particle diameter were prepared by five different types of mills. The flowability index (FI) and the particle shape indices, namely, Wadell's working sphericity Ψ W and circularity Ψ C, of five kinds of test powders were measured. The effect of the comminuting mechanisms on the flowability of ground powders was investigated, and the relationship between the flowability of ground powders and the particle shape indices was analyzed. The experimental results show that the ground powders obtained by collision have irregular particle shapes and smooth surfaces, showing a high flowability. On the other hand, though the particle obtained by grinding is close to a spherical particle, but it has a rugged surface, and shows a bad flowability. Furthermore, the flowability index is more correlated with the circularity than the working sphericity is. This means that the surface roughness is more effective in determining the flowability of powders than the roundness is.
文摘Based upon the aspect of continuous damaging,the process of ore comminution may be des- cribed as the growth and propagation of the microcracks in the ore grains under external load- ing,and a theoretical expression has been developed on the relationship between the grain size distribution and the total energy consumption during entire ore comminution process.The en- ergy consumed totally may be considered consisting of two portions,i.e.with fresh crack sur- faces growth and with crack propagation.The proposed expression seems to be an advance over previous conventional ones,especially that from the viewpoint of energy distribution.
文摘In this paper, the main factors that influence on qualities of kaolin in the area are revealed by studying the properties of coal-series kaolin in Enshi, Hubei (P. R. China), technologies of ferrum and carbon elimination for coal-series kaolin are investigated , and ways to fully uti-lize the resource are hopeful to be sought.