Al-20Si-5Fe-3Cu-1Mg alloy was synthesized by the spray atomization and deposition technique. The microstructure and mechanical properties of the spray deposited hypereutectic Al-Si alloy were studied using optical mic...Al-20Si-5Fe-3Cu-1Mg alloy was synthesized by the spray atomization and deposition technique. The microstructure and mechanical properties of the spray deposited hypereutectic Al-Si alloy were studied using optical microscopy, scanning electron microscopy, X-ray diffraction, TEM (Transmission Electron Microscope) and HREM (High-resolution Electron Microscope), DSC (Differential Scanning Calorimetry), microhardness measurement, and tensile tests. The effects of Mn on the microstructural evolution of the high-silicon aluminum alloy after extrusion and heat treatment have been examined. The results show that two kinds of phases, i. e. S (Al2CuMg) and σ(Al5Cu6,Mg2), precipitated from matrix and improved the tensile strength of the alloy efficiently at both the ambient and elevated temperatures (300℃). The tensile test results indicate that the spray-deposited Al-20Si-5Fe-3Cu-1Mg alloy has better strength than the powder metallurgy processed Al-20Si-3Cu-1Mg alloy at elevated temperature.展开更多
BACKGROUND： The abnormal posture and motor pattern have not stabilized in children with cerebral palsy at early period, thus timely treatment can establish normal postural reflex and motor pattern, and prevent compli...BACKGROUND： The abnormal posture and motor pattern have not stabilized in children with cerebral palsy at early period, thus timely treatment can establish normal postural reflex and motor pattern, and prevent complications of muscle contracture, ankylosis, skeletal deformity, etc. The clinical factors affecting the rehabilitative efficacy of gross motor function in children with cerebral palsy should be observed. OBJECTIVE： To observe the effects of therapeutic occasion, grading of gross motor function and developmental level on the rehabilitative efficacy in children with cerebral palsy. DESIGN： A case-controlled analysis. SETTING： Qilu Children＇s Hospital of Shandong University. PARTICIPANTS： Totally 138 children with cerebral palsy, who were hospitalized for 12 months in the Rehabilitation Center of Qilu Children＇s Hospital, Shandong University, were selected from April 2004 to September 2006, and all the children were diagnosed to be accorded with the standard set by the national seminar on cerebral palsy in 2004. There were 97 males and 41 females, including 55 cases of 0-2 years old, 47 cases of 2-4 years and 36 cases of 4-6 years. Informed contents were obtained from relatives of all the children. METHODS： ① Comprehensive rehabilitation treatment： Vojta method was to induce the children to turn over the body and crawl by stimulating reflective turn over and crawling on belly. Bobath method including trainings of head control, turning over body, keeping sitting position, keeping balance, crawling, keeping standing position, and walking, etc.; The children were massaged by using the maneuvers of push, press, rub, pull, wave, etc. according to the sites and types of palsy. Acupuncture was performed mainly at bilateral motor areas, the needle was retained for 1 hour per time, 6 days continuously every week, and followed by a 1-day interval. ② Prognosis assessment： The gross motor functional grading of the children with cerebral palsy at admission was assessed using the Chinese version of gross motor function classification system （GMFCS）. The gross motor functions of the children with cerebral palsy were assessed before rehabilitation treatment and 12 months after rehabilitation treatment by using gross motor function measure （GMFM）. The improved GMFM total score was calculated. Developmental quotient was evaluated using Gesell developmental schedules （GDS） after 12-month rehabilitation treatment. Univariate analysis of variance was performed using the improved GMFM total score with age, GMFCS grade and developmental level （developmental quotient）. MAIN OUTCOME MEASURES： Effects of age started to accept rehabilitation treatment, GMFCS grade and developmental level on the recovery of gross motor function in children with cerebral palsy. RESULTS： All the 138 children with cerebral palsy were involved in the analysis of results. The improved GMFM total scores were significantly different among the children with cerebral palsy of different ages started to accept treatment, GMFCS grades and developmental levels （F=13.464, 37.283, 30.814, P 〈 0.01）. The younger the children started to accept treatment, the lower the their GMFCS grades and the higher their developmental levels, then the higher their improved GMFM total scores. CONCLUSION： The recovery of gross motor function is better in younger children started to accepted treatment with cerebral palsy with lower GMFCS grades and higher developmental levels.展开更多
基金This works was financially supported by "863 " key foundation of China (No. 863-715-009-003).
文摘Al-20Si-5Fe-3Cu-1Mg alloy was synthesized by the spray atomization and deposition technique. The microstructure and mechanical properties of the spray deposited hypereutectic Al-Si alloy were studied using optical microscopy, scanning electron microscopy, X-ray diffraction, TEM (Transmission Electron Microscope) and HREM (High-resolution Electron Microscope), DSC (Differential Scanning Calorimetry), microhardness measurement, and tensile tests. The effects of Mn on the microstructural evolution of the high-silicon aluminum alloy after extrusion and heat treatment have been examined. The results show that two kinds of phases, i. e. S (Al2CuMg) and σ(Al5Cu6,Mg2), precipitated from matrix and improved the tensile strength of the alloy efficiently at both the ambient and elevated temperatures (300℃). The tensile test results indicate that the spray-deposited Al-20Si-5Fe-3Cu-1Mg alloy has better strength than the powder metallurgy processed Al-20Si-3Cu-1Mg alloy at elevated temperature.
文摘BACKGROUND： The abnormal posture and motor pattern have not stabilized in children with cerebral palsy at early period, thus timely treatment can establish normal postural reflex and motor pattern, and prevent complications of muscle contracture, ankylosis, skeletal deformity, etc. The clinical factors affecting the rehabilitative efficacy of gross motor function in children with cerebral palsy should be observed. OBJECTIVE： To observe the effects of therapeutic occasion, grading of gross motor function and developmental level on the rehabilitative efficacy in children with cerebral palsy. DESIGN： A case-controlled analysis. SETTING： Qilu Children＇s Hospital of Shandong University. PARTICIPANTS： Totally 138 children with cerebral palsy, who were hospitalized for 12 months in the Rehabilitation Center of Qilu Children＇s Hospital, Shandong University, were selected from April 2004 to September 2006, and all the children were diagnosed to be accorded with the standard set by the national seminar on cerebral palsy in 2004. There were 97 males and 41 females, including 55 cases of 0-2 years old, 47 cases of 2-4 years and 36 cases of 4-6 years. Informed contents were obtained from relatives of all the children. METHODS： ① Comprehensive rehabilitation treatment： Vojta method was to induce the children to turn over the body and crawl by stimulating reflective turn over and crawling on belly. Bobath method including trainings of head control, turning over body, keeping sitting position, keeping balance, crawling, keeping standing position, and walking, etc.; The children were massaged by using the maneuvers of push, press, rub, pull, wave, etc. according to the sites and types of palsy. Acupuncture was performed mainly at bilateral motor areas, the needle was retained for 1 hour per time, 6 days continuously every week, and followed by a 1-day interval. ② Prognosis assessment： The gross motor functional grading of the children with cerebral palsy at admission was assessed using the Chinese version of gross motor function classification system （GMFCS）. The gross motor functions of the children with cerebral palsy were assessed before rehabilitation treatment and 12 months after rehabilitation treatment by using gross motor function measure （GMFM）. The improved GMFM total score was calculated. Developmental quotient was evaluated using Gesell developmental schedules （GDS） after 12-month rehabilitation treatment. Univariate analysis of variance was performed using the improved GMFM total score with age, GMFCS grade and developmental level （developmental quotient）. MAIN OUTCOME MEASURES： Effects of age started to accept rehabilitation treatment, GMFCS grade and developmental level on the recovery of gross motor function in children with cerebral palsy. RESULTS： All the 138 children with cerebral palsy were involved in the analysis of results. The improved GMFM total scores were significantly different among the children with cerebral palsy of different ages started to accept treatment, GMFCS grades and developmental levels （F=13.464, 37.283, 30.814, P 〈 0.01）. The younger the children started to accept treatment, the lower the their GMFCS grades and the higher their developmental levels, then the higher their improved GMFM total scores. CONCLUSION： The recovery of gross motor function is better in younger children started to accepted treatment with cerebral palsy with lower GMFCS grades and higher developmental levels.
