A new blasting approach of combined blastholes with different diameters is proposed to solve the problems of oversize boulders and rock toes in open-pit mine. A non-ideal detonation model and a statistical damage cons...A new blasting approach of combined blastholes with different diameters is proposed to solve the problems of oversize boulders and rock toes in open-pit mine. A non-ideal detonation model and a statistical damage constitutive model are implemented in dynamic finite element analysis to investigate the formation mechanism of oversize boulders and toes. The damage distribution and evolution process of rock blasting fragmentation is simulated, and the scheme is further optimized. Numerical analysis results showed that pocket charges and satellite blastholes can only improve bench top fragmentation, but they cannot reduce the oversize in the middle and bottom of bench as well as the toe problem. The new blasting approach of combined blastholes with different diameters can effectively reduce the oversize boulders and toes as well as the production costs.展开更多
BACKGROUND Cholesterol crystal embolization(CCE)is a multisystemic and fatal disease with multiple clinical manifestations;however,there are few cases of idiopathic CCE.Here we report a patient with idiopathic CCE acc...BACKGROUND Cholesterol crystal embolization(CCE)is a multisystemic and fatal disease with multiple clinical manifestations;however,there are few cases of idiopathic CCE.Here we report a patient with idiopathic CCE accompanied by atheroembolic renal disease and blue toes who had a relatively good prognosis in the short-term due to early treatment with corticosteroids and statins.CASE SUMMARY A 76-year-old man complained of coldness,numbness and purple color change in his left foot for 7 d.He had a feeling of fatigue,constipation,foamy urine,poor appetite and sleep.He had a lacunar infarction for 5 years and hypertension for 9 mo.Laboratory results showed elevated eosinophils,cholesterol,uric acid,serum creatinine,urea and 24 h urine analysis revealed proteinuria.A renal biopsy revealed atheroembolic renal disease.Taken together,these findings strongly supported the diagnosis of idiopathic CCE and atheroembolic renal disease.CONCLUSION Atheroembolic renal disease and blue toes syndrome can be caused by idiopathic CCE,and early treatment with corticosteroids is effective but requires further investigation.展开更多
Located on eastern slope of Mingsha Mountain and the west bank of Dangquan River,which is 25 km to the southeast of Dunhuang city,Mogao Grottoes were first constructed in366 A.D.and continuously built for around1,000 ...Located on eastern slope of Mingsha Mountain and the west bank of Dangquan River,which is 25 km to the southeast of Dunhuang city,Mogao Grottoes were first constructed in366 A.D.and continuously built for around1,000 years across 11 dynasties or periods.展开更多
基金supported by Chinese National Natural Science Foundation (No. 51809016 and No. 51979152)Chongqing Municipal Natural Science Foundation (No. cstc2019jcyjmsxmX0645)
文摘A new blasting approach of combined blastholes with different diameters is proposed to solve the problems of oversize boulders and rock toes in open-pit mine. A non-ideal detonation model and a statistical damage constitutive model are implemented in dynamic finite element analysis to investigate the formation mechanism of oversize boulders and toes. The damage distribution and evolution process of rock blasting fragmentation is simulated, and the scheme is further optimized. Numerical analysis results showed that pocket charges and satellite blastholes can only improve bench top fragmentation, but they cannot reduce the oversize in the middle and bottom of bench as well as the toe problem. The new blasting approach of combined blastholes with different diameters can effectively reduce the oversize boulders and toes as well as the production costs.
文摘BACKGROUND Cholesterol crystal embolization(CCE)is a multisystemic and fatal disease with multiple clinical manifestations;however,there are few cases of idiopathic CCE.Here we report a patient with idiopathic CCE accompanied by atheroembolic renal disease and blue toes who had a relatively good prognosis in the short-term due to early treatment with corticosteroids and statins.CASE SUMMARY A 76-year-old man complained of coldness,numbness and purple color change in his left foot for 7 d.He had a feeling of fatigue,constipation,foamy urine,poor appetite and sleep.He had a lacunar infarction for 5 years and hypertension for 9 mo.Laboratory results showed elevated eosinophils,cholesterol,uric acid,serum creatinine,urea and 24 h urine analysis revealed proteinuria.A renal biopsy revealed atheroembolic renal disease.Taken together,these findings strongly supported the diagnosis of idiopathic CCE and atheroembolic renal disease.CONCLUSION Atheroembolic renal disease and blue toes syndrome can be caused by idiopathic CCE,and early treatment with corticosteroids is effective but requires further investigation.
文摘Located on eastern slope of Mingsha Mountain and the west bank of Dangquan River,which is 25 km to the southeast of Dunhuang city,Mogao Grottoes were first constructed in366 A.D.and continuously built for around1,000 years across 11 dynasties or periods.
