BACKGROUND Stroke is a type of cerebrovascular disease with high prevalence,mortality,and onset of disability.As a neurodevelopmental therapy,neuromuscular joint facilitation(NJF)is widely used in the treatment of ort...BACKGROUND Stroke is a type of cerebrovascular disease with high prevalence,mortality,and onset of disability.As a neurodevelopmental therapy,neuromuscular joint facilitation(NJF)is widely used in the treatment of orthopedic and neurological disorders in the clinical practice.It is mainly used for central nervous system diseases or orthopedic diseases,movement disorders,and pain rehabilitation.According to related studies,NJF can also be used as a rehabilitation treatment in patients with hemiplegic shoulder pain(HSP).AIM To investigate the clinical efficacy of acupuncture combined with NJF in patients with HSP.METHODS Forty patients with HSP were randomly divided into a treatment group and a control group.The treatment group was treated with acupuncture combined with NJF and the control group was treated with acupuncture alone.All patients were assessed by using the visual analogue scale(VAS),Fugl-Meyer assessment(FMA),Barthel index(BI),and passive range of motion(PROM)before and after the training.All the clinical data were analyzed using SPSS 20.0 statistical software.RESULTS There was no statistical difference in the general characteristics between the two groups.In the terms of duration of treatment,age,and pre-treatment indicators,the two groups were comparable(P>0.05).After the treatment,VAS,PROM,BI,and FMA scores were significantly improved in the two groups of patients(P<0.05).The VAS,PROM and FMA scores were significantly higher in the treatment group than in the control group(P<0.05).However,there was no significant difference in BI scores between the two groups(P>0.05).CONCLUSION Both acupuncture alone and acupuncture combined with NJF in the treatment of HSP are effective,and can improve the clinical symptoms of patients.Acupuncture combined with NJF can improve the upper limb motor function,relieve pain,and increase joint mobility in patients with HSP.The combination therapy is better than acupuncture alone.However,there is no significant difference in improving the score of patients’self-care ability.展开更多
Objective To observe the clinical effect of acupuncture on the obsolete lateral malleolus joint sprain. Methods Thirty-one cases of patients with obsolete lateral malleolus joint sprain were selected. Jiexi (解溪 ST...Objective To observe the clinical effect of acupuncture on the obsolete lateral malleolus joint sprain. Methods Thirty-one cases of patients with obsolete lateral malleolus joint sprain were selected. Jiexi (解溪 ST 41) were penetrated to Shenmei (申脉 BL 61), and Yanglingquan (阳陵泉 GB 34) was applied. The needles were retained for 30 min, and the treatment was performed only once, with follow-up visit after 1 month. Results All the patients were cured after treatment, and without relapse on the follow-up visit after 1 month. Conclusion The clinical effect of acupuncture on the obsolete lateral malleolus joint sprain is remarkable.展开更多
Objective To observe the effects of acupuncture and massage to improve the mobility of affected shoulder joint caused by acute cerebral infarction. Methods 120 cases of acute cerebral infarction were randomized into t...Objective To observe the effects of acupuncture and massage to improve the mobility of affected shoulder joint caused by acute cerebral infarction. Methods 120 cases of acute cerebral infarction were randomized into two groups, named treatment group with acupuncture and massage and control group with western medicine. Acupoint selection of treatment group with acupuncture and massage: Yōngquán (涌泉 KI1), Láogōng (劳宫 PC8), Hòuxī (后溪SI3), Gōngsūn (公孙 SP4), Fēngchī (风池 GB20), Jiānyú (肩髃 LI15), Qūchí (曲池 LI11), Hégǔ (合谷 LI4), Huántiào (环跳 GB30), Zúsānlǐ (足三里 ST36), Tàichōng (太冲 LR3), Anterior Oblique Line of Vertex-Temporal and Posterior Oblique Line of Vertex-Temporal. Massage techniques: roll for relax, hold and press, flick and fiddle, and shake. Control group with western medicine was treated with mannitol + low molecular weight dextran + CDP-choline. Results Compared with control group, treatment group could apparently improve the mobility of shoulder joint and lower the injury percentage (P〈0. 01) ; and the therapeutic effect of treatment group is better than that of control group (P〈0. 05) for treating acute cerebral infarction. Conclusion The therapy of acupuncture combined with massage could improve the function of the affected shoulder joint caused by acute cerebral infarction, and enhance therapeutic effect.展开更多
The fatigue property of AZ31 magnesium alloy and its TIG welded joints were investigated. The ultrasonic peening treatment (UPT) was used to improve the fatigue property of the TIG welded joints, which was treated a...The fatigue property of AZ31 magnesium alloy and its TIG welded joints were investigated. The ultrasonic peening treatment (UPT) was used to improve the fatigue property of the TIG welded joints, which was treated at the weld toe by the UPT process. The test results show that the fatigue strength of the base metal of AZ31 magnesium alloys is 57.8 MPa, and those of the fillet joint and the transverse cross joint are respectively 20. 0 MPa and 17.2 MPa at 2 × 10^6 cycles. The fatigue strengths of two kinds of welded joints treated by the UPT are respectively 30. 3 MPa and 24. 7 MPa, which have been improved by 51.5% and 43.6%, respectively. The fatigue life of the fillet joint specimens is prolonged by about 2. 74 times and the fatigue life of the transverse cross joint specimens is prolonged by about 1.05 times when the stress range is at 40. 0 MPa.展开更多
To get the movement mode and driving mechanism similar to human shoulder joint,a six degrees of freedom(DOF) serial-parallel bionic shoulder joint mechanism driven by pneumatic muscle actuators(PMAs)was designed.Howev...To get the movement mode and driving mechanism similar to human shoulder joint,a six degrees of freedom(DOF) serial-parallel bionic shoulder joint mechanism driven by pneumatic muscle actuators(PMAs)was designed.However,the structural parameters of the shoulder joint will affect various performances of the mechanism.To obtain the optimal structure parameters,the particle swarm optimization(PSO) was used.Besides,the mathematical expressions of indexes of rotation ranges,maximum bearing torque,discrete dexterity and muscle shrinkage of the bionic shoulder joint were established respectively to represent its many-sided characteristics.And the multi-objective optimization problem was transformed into a single-objective optimization problem by using the weighted-sum method.The normalization method and adaptive-weight method were used to determine each optimization index's weight coefficient;then the particle swarm optimization was used to optimize the integrated objective function of the bionic shoulder joint and the optimal solution was obtained.Compared with the average optimization generations and the optimal target values of many experiments,using adaptive-weight method to adjust weights of integrated objective function is better than using normalization method,which validates superiority of the adaptive-weight method.展开更多
Strong metal/non-polar plastic dissimilar joints are highly demanded for the lightweight design in many fields,which,however,are rather challenging to achieve directly via welding.In this study,we designed a laser pro...Strong metal/non-polar plastic dissimilar joints are highly demanded for the lightweight design in many fields,which,however,are rather challenging to achieve directly via welding.In this study,we designed a laser processing pretreatment on the Al alloy to create a deep porous Al surface structure,which was successfully joined to the polypropylene(PP) via friction spot welding.A maximum joint strength of29 MPa was achieved,the same as that of the base PP(i.e.the joint efficiency reached 100%),much larger than ever reported.The joining mechanism of the Al alloy and the PP was mainly attributed to the large mechanical interlocking effect between the laser processed Al porous structure and the re-solidified PP and the formation of chemical bond at the interface.The deep porous Al surface structure modified by laser processing largely changed the Al-PP reaction feature.The evidence of the C-O-Al chemical bond was first time found at the non-polar plastic/Al joint interface,which was the reaction result between the oxide on the Al alloy surface and thermal oxidization products of the PP during welding.This study provides a new way for enhancing metal-plastic joints via surface laser treatment techniques.展开更多
The authors have treated 50 cases of frozen shoulder in recent years with electro-acupuncture and the elevation manipulation. The results were satisfactory and reported as follows.
Friction stir welding (FSW) and stationary shoulder friction stir welding (SSFSW) were carried out for the butt joining of dissimilar AA2024-T3 and AA7050-T7651 aluminium alloys with thicknesses of 2 mm. A compari...Friction stir welding (FSW) and stationary shoulder friction stir welding (SSFSW) were carried out for the butt joining of dissimilar AA2024-T3 and AA7050-T7651 aluminium alloys with thicknesses of 2 mm. A comparison between the two processes was performed by varying the welding speed while keeping the rotational speed constant, Through the analysis of the force and torque produced during welding and a simple analytical model, it was possible to show that in SSFSW there is more effective coupling with the tool and the heat produced is more efficiently distributed. This process decreases both the welding area and the diffusion at the interface of the two alloys compared with FSW. The minimum microhardness occurred at the advancing side (AS) at the interface between the thermo-mechanically affected zone (TMAZ) and the stir zone (SZ) in both processes, although the decrease was more gradual in SSFSW. This interface is also where all specimens failed for both welding technologies. An increase in tensile strength was measured in SSFSW compared with standard FSW. Furthermore, it was possible to establish the mechanical performance of the material in the fracture zone using digital image correlation.展开更多
BACKGROUND Non-albicans Candida prosthetic joint infections (PJIs) are rare. Optimal treatment involves a two-stage revision surgery in combination with an antifungal agent. However, no clear guidelines have been deve...BACKGROUND Non-albicans Candida prosthetic joint infections (PJIs) are rare. Optimal treatment involves a two-stage revision surgery in combination with an antifungal agent. However, no clear guidelines have been developed regarding the agent or treatment duration. Hence, a broad range of antifungal and surgical treatments have been reported so far. AIM To clarify treatment of non-albicans Candida PJIs. METHODS A literature review of all existing non-albicans Candida PJIs cases through April 2018 was conducted. Information was extracted about demographics, comorbidities, responsible species, duration and type of antifungal treatment, type of surgical treatment, time between initial arthroplasty and symptom onset, time between symptom onset and definite diagnosis, outcome of the infection and follow-up. RESULTS A total of 83 cases, with a mean age of 66.3 years, were located. The causative yeast isolated in most cases was C. parapsilosis (45 cases;54.2%), followed by C. glabrata (18 cases;21.7%). The mean Charlson comorbidity index was 4.4 ± 1.5. The mean time from arthropalsty to symptom onset was 27.2 ± 43 mo, while the mean time from symptom onset to culture-confirmed diagnosis was 7.5 ± 12.5 mo. A two stage revision arthroplasty (TSRA), when compared to one stage revision arthroplasty, had a higher success rate (96% vs 73%, P = 0.023). Fluconazole was the preferred antifungal agent (59;71%), followed by amphotericin B (41;49.4%). CONCLUSION The combination of TSRA and administration of prolonged antifungal therapy after initial resection arthroplasty is suggested on the basis of limited data.展开更多
A pipeline steel X80 with welded joint was subjected to surface mechanical attrition treatment (SMAT). After SMAT, a nanostructure surface layer with an average grain size of about 10 nm was formed in the treated sa...A pipeline steel X80 with welded joint was subjected to surface mechanical attrition treatment (SMAT). After SMAT, a nanostructure surface layer with an average grain size of about 10 nm was formed in the treated sample, and the fatigue limit of the welded joint was elevated by about 13% relative to the untreated joints. In the low and the high amplitude stress regimes, both fatigue strength and fatigue life were enhanced. Formation of the nanostructured surface layer played more important role in the enhanced fatigue behavior than that of residual stress induced by the SMAT.展开更多
The dissimilar metals 1Crl8Ni9 and 16MnR are welded by shielded metal arc welding process using electrode A312. The corrosion experiments are carried out on welded joint samples, which is as-welded and post-weld heat ...The dissimilar metals 1Crl8Ni9 and 16MnR are welded by shielded metal arc welding process using electrode A312. The corrosion experiments are carried out on welded joint samples, which is as-welded and post-weld heat treatment at 650 ℃, 750 ℃ and 850 ℃, for 2 h in 70% sodium hydroxide solution. EDS and X-ray diffraction analysis are carried out on the samples after corrosion. Average corrosion rate calculation and microhardness measurement are conducted on both as- welded and post-weld heat treatment samples. The results indicate that average corrosion rate of as-welded joint metal is smaller than that of post-weld heat treatment joint metal. Compared with that of post-weld heat treatment at 750 ℃ and 850 ℃ for 2 h, the average corrosion rate of welded joint after post-weld heat treatment at 650 ℃ for 2 h increases greatly.展开更多
The surface of 1Cr5 Mo heat-resistant steel welding joint was processed with CO2 laser, and the corrosion behaviors before and after laser heat treatment(LHT) were investigated in the salt spray corrosion environments...The surface of 1Cr5 Mo heat-resistant steel welding joint was processed with CO2 laser, and the corrosion behaviors before and after laser heat treatment(LHT) were investigated in the salt spray corrosion environments. The microstructures, phases, residual stresses and retained austenite content of 1Cr5 Mo steel welding joint before and after LHT were analyzed with optical microscope and X-ray diffraction, respectively. The cracking morphologies and chemical compositions of corrosion products after salt spray corrosion were analyzed with field emission scanning electron microscopy(FESEM) and energy disperse spectroscopy(EDS), respectively, the polarization curves were measured on a PS-268 A type electrochemical workstation, and the mechanism of corrosion resistance by LHT was investigated as well. The results show that the passive film of original sample is destroyed owing to the corrosive media penetrating into the subsurface, resulting in the redox reaction. The content of residual austenite in the surface and the self-corrosion potential are increased by LHT, which is contributed to improving the capability of salt spray corrosion resistance.展开更多
With the development of an IT (Information Technology) society, the opportunity to use electronic devices, such as cell phones and personal computers, has increased. These electronic devices pro-vide many benefits to ...With the development of an IT (Information Technology) society, the opportunity to use electronic devices, such as cell phones and personal computers, has increased. These electronic devices pro-vide many benefits to society. However, there have been a number of reports of electromagnetic hypersensitivity (EHS) related to the use of electronic devices. The symptoms of EHS may include headaches, fatigue, tinnitus, dizziness, memory loss, irregular heartbeat, and skin trouble. Since the pathogenic mechanism of such conditions is not yet clear, further research is required. This report shows how a subject’s dizziness and joint mobility disorder, caused by electromagnetic waves emitted by electronic devices, were cured by removing an onlay from the patient’s mouth and replacing it with a gold alloy onlay. The result indicates that the subject’s symptoms were caused by EHS. Although the symptoms were improved after the dental treatment, the underlying mechanism of the symptoms and the reason why this treatment is successful remain unclear. Further research is required to clarify these issues.展开更多
BACKGROUND Condylar osteophytes,a remodeling form of temporomandibular joint osteoarthritis(TMJ OA),mainly manifest as marginal angular outgrowths of the condyle.Previous researchers have advocated surgical removal of...BACKGROUND Condylar osteophytes,a remodeling form of temporomandibular joint osteoarthritis(TMJ OA),mainly manifest as marginal angular outgrowths of the condyle.Previous researchers have advocated surgical removal of condylar osteophytes.Reports on the effect of occlusal splint on TMJ OA patients’joints have mostly focused on treatment with this splint,which can reduce the absorption of the affected condyle and promote repair and regeneration.However,the effect of the splint on the dissolution of condylar osteophytes has not yet been reported.CASE SUMMARY A 68-year-old female patient suffered from occlusal discomfort with left facial pain for 2 years.Cone beam computed tomography showed a rare osteophyte on top of her left condyle.She was finally diagnosed with TMJ OA.The patient refused surgical treatment and received conservative treatment with a muscle balance occlusal splint.The pain experienced by the patient on the left side of her face was relieved,and her chewing ability recovered after treatment.The osteophyte dissolved,and the condylar cortex remained stable during long-term follow-up observations.CONCLUSION The muscle balance occlusal splint could be a noninvasive means of treating condylar osteophytes in TMJ OA patients.展开更多
Tungsten inert gas(TIG) welding was performed on 2.7 mm thick commercial extruded AZ31 B magnesium alloy plates. We investigated the effect of post-weld heat treatment(PWHT) on the microstructure, mechanical prope...Tungsten inert gas(TIG) welding was performed on 2.7 mm thick commercial extruded AZ31 B magnesium alloy plates. We investigated the effect of post-weld heat treatment(PWHT) on the microstructure, mechanical properties and precipitated phase of the weld joints. The results showed that during the annealing treatment(200 ℃-1 h, 250 ℃-1 h, 300 ℃-1 h, 350 ℃-1 h, 400 ℃-1 h, and 450 ℃-1 h), the average grain size in the weld seam was the minimum after annealing at 400 ℃ for 1 hour, and then abnormally grew up after annealing at 450 ℃ for 1 hour. The mechanical properties enhanced when the joints were processed from 200 ℃-1 h to 400 ℃-1 h but sharply decreased with increasing annealing temperature. In contrast to the annealing treatment, solution treatment(250 ℃-10 h, 300 ℃-10 h, 350 ℃-10 h, 400 ℃-10 h, and 450 ℃-10 h) exhibited a better ductility but a slight deterioration in tensile strength. Especially speaking, no eutectic compounds(such as Mg17 Al12) were observed in the weld seam. The supersaturated Al atoms were precipitated in a coarse spherical shape dispersed in the weld seam. The precipitated Al atoms dissolved in the matrix substances at the condition(400 ℃-1 h) or(250 ℃-10 h). The solution treatment caused grain coarsening and precipitated Al atoms dissolved in the weld seam substantially, which resulted in a drop in micro-hardness at the weld seam compared to the area of the annealed joints.展开更多
Improvement of the fatigue life of welded tubular T-joints in offshore platforms due to weld toe grinding and TIG dressing is studied physically and experimentally. It is shown that the two methods of treatment can im...Improvement of the fatigue life of welded tubular T-joints in offshore platforms due to weld toe grinding and TIG dressing is studied physically and experimentally. It is shown that the two methods of treatment can improve the fatigue strength of welded tubular joints not only in the environment of air but even in the envirnment of seawater accordingly.展开更多
The electron beam local post-weld heat treatment (EBLPWHT) is a rather new method that provides the advantages of high precision, flexibility and efficiency, energy saving and higher productivity. This paper studies t...The electron beam local post-weld heat treatment (EBLPWHT) is a rather new method that provides the advantages of high precision, flexibility and efficiency, energy saving and higher productivity. This paper studies the effect of two post-weld heat treatment processes on the microstructure, mechanical properties and fracture toughness of an electron beam welded joints in 30CrMnSiNi2A steel. EBLPWHT, in a vacuum chamber, immediately after welding and a traditional furnace whole post-weld heat treatment (FWPWHT) were compared. The experimental results show that, after EBLPWHT treatment, the main microstructure of weld was changed from coarse acicular martensite into lath martensite, HAZ was changed from lath martensite, bainite into lower bainite, and base metal was changed from ferrite and pearlite into upper bainite and residual austenite. The microstructures of different zones of joints in FWPWHT condition were tempered sorbite. The properties of welded joints can be improved by the EBLPWHT in some extent, and especially largely for the fracture toughness of welded joints. However the value of fracture toughness of base metal is comparatively low, so appropriate heat treatment parameters should be explored in the future.展开更多
In this study, 3-mm-thick hot-extruded plates of A1-12.7Si-0.7Mg alloy were used to fabricate the joints welded by gas metal arc welding. Effects of the post-weld heat treatment include solid solution treatment, water...In this study, 3-mm-thick hot-extruded plates of A1-12.7Si-0.7Mg alloy were used to fabricate the joints welded by gas metal arc welding. Effects of the post-weld heat treatment include solid solution treatment, water quenching, and artificial aging treatment on the microstructure, and mechanical properties of the weld joints have been investigated. Results showed that the welded joints after solid solution and artificial aging exhibited the increases in yield strength of 166 MPa and ultimate tensile strength of 148 MPa, respectively. Based on the microstructural observations, the associated mechanisms were discussed.展开更多
AIM To evaluate the joint geometry and the clinical outcome of stemless,anatomical shoulder arthroplasty with the TESS system.METHODS Twenty-one shoulders with a mean follow-up 18 of months were included.On scaled dig...AIM To evaluate the joint geometry and the clinical outcome of stemless,anatomical shoulder arthroplasty with the TESS system.METHODS Twenty-one shoulders with a mean follow-up 18 of months were included.On scaled digital radiographs the premorbid center of rotation(CoR)was assessed and compared to the CoR of the prosthesis by using the MediC AD~?software.Additionally,the pre-and post-operative geometry of the CoR was assessed in relation to the glenoid,the acromion as well as to the proximal humerus.Radiological changes,such as radiolucencies,were also assessed.Clinical outcome was assessed with the Constant and DASH score.RESULTS Both,the Constant and DASH scores improved signifi-cantly from 11%to 75%and from 70 to 30 points,P<0.01 respectively.There were no significant differences regarding age,etiology,cemented or metal-backed glenoids,etc.(P>0.05).The pre-and postoperative humeral offset,the lateral glenohumeral offset,the height of the CoR,the acromiohumeral distance as well as neckshaft angle showed no significant changes(P>0.05).The mean deviation of the CoR of the prosthesis from the anatomic center was 1.0±2.8 mm.Three cases showed a medial deviation of more than 3 mm.These deviations of 5.1,5.7 and 7.6 mm and were caused by an inaccurate humeral neck cut.These 3 patients showed a relatively poor outcome scoring.CONCLUSION TESS arthroplasty allows an anatomical joint reconstruction with a very good outcome.Outliers described in this study sensitize the surgeon for an accurate humeral neck cut.展开更多
文摘BACKGROUND Stroke is a type of cerebrovascular disease with high prevalence,mortality,and onset of disability.As a neurodevelopmental therapy,neuromuscular joint facilitation(NJF)is widely used in the treatment of orthopedic and neurological disorders in the clinical practice.It is mainly used for central nervous system diseases or orthopedic diseases,movement disorders,and pain rehabilitation.According to related studies,NJF can also be used as a rehabilitation treatment in patients with hemiplegic shoulder pain(HSP).AIM To investigate the clinical efficacy of acupuncture combined with NJF in patients with HSP.METHODS Forty patients with HSP were randomly divided into a treatment group and a control group.The treatment group was treated with acupuncture combined with NJF and the control group was treated with acupuncture alone.All patients were assessed by using the visual analogue scale(VAS),Fugl-Meyer assessment(FMA),Barthel index(BI),and passive range of motion(PROM)before and after the training.All the clinical data were analyzed using SPSS 20.0 statistical software.RESULTS There was no statistical difference in the general characteristics between the two groups.In the terms of duration of treatment,age,and pre-treatment indicators,the two groups were comparable(P>0.05).After the treatment,VAS,PROM,BI,and FMA scores were significantly improved in the two groups of patients(P<0.05).The VAS,PROM and FMA scores were significantly higher in the treatment group than in the control group(P<0.05).However,there was no significant difference in BI scores between the two groups(P>0.05).CONCLUSION Both acupuncture alone and acupuncture combined with NJF in the treatment of HSP are effective,and can improve the clinical symptoms of patients.Acupuncture combined with NJF can improve the upper limb motor function,relieve pain,and increase joint mobility in patients with HSP.The combination therapy is better than acupuncture alone.However,there is no significant difference in improving the score of patients’self-care ability.
文摘Objective To observe the clinical effect of acupuncture on the obsolete lateral malleolus joint sprain. Methods Thirty-one cases of patients with obsolete lateral malleolus joint sprain were selected. Jiexi (解溪 ST 41) were penetrated to Shenmei (申脉 BL 61), and Yanglingquan (阳陵泉 GB 34) was applied. The needles were retained for 30 min, and the treatment was performed only once, with follow-up visit after 1 month. Results All the patients were cured after treatment, and without relapse on the follow-up visit after 1 month. Conclusion The clinical effect of acupuncture on the obsolete lateral malleolus joint sprain is remarkable.
文摘Objective To observe the effects of acupuncture and massage to improve the mobility of affected shoulder joint caused by acute cerebral infarction. Methods 120 cases of acute cerebral infarction were randomized into two groups, named treatment group with acupuncture and massage and control group with western medicine. Acupoint selection of treatment group with acupuncture and massage: Yōngquán (涌泉 KI1), Láogōng (劳宫 PC8), Hòuxī (后溪SI3), Gōngsūn (公孙 SP4), Fēngchī (风池 GB20), Jiānyú (肩髃 LI15), Qūchí (曲池 LI11), Hégǔ (合谷 LI4), Huántiào (环跳 GB30), Zúsānlǐ (足三里 ST36), Tàichōng (太冲 LR3), Anterior Oblique Line of Vertex-Temporal and Posterior Oblique Line of Vertex-Temporal. Massage techniques: roll for relax, hold and press, flick and fiddle, and shake. Control group with western medicine was treated with mannitol + low molecular weight dextran + CDP-choline. Results Compared with control group, treatment group could apparently improve the mobility of shoulder joint and lower the injury percentage (P〈0. 01) ; and the therapeutic effect of treatment group is better than that of control group (P〈0. 05) for treating acute cerebral infarction. Conclusion The therapy of acupuncture combined with massage could improve the function of the affected shoulder joint caused by acute cerebral infarction, and enhance therapeutic effect.
基金the National Natural Science Foundation of China (No.50675148)
文摘The fatigue property of AZ31 magnesium alloy and its TIG welded joints were investigated. The ultrasonic peening treatment (UPT) was used to improve the fatigue property of the TIG welded joints, which was treated at the weld toe by the UPT process. The test results show that the fatigue strength of the base metal of AZ31 magnesium alloys is 57.8 MPa, and those of the fillet joint and the transverse cross joint are respectively 20. 0 MPa and 17.2 MPa at 2 × 10^6 cycles. The fatigue strengths of two kinds of welded joints treated by the UPT are respectively 30. 3 MPa and 24. 7 MPa, which have been improved by 51.5% and 43.6%, respectively. The fatigue life of the fillet joint specimens is prolonged by about 2. 74 times and the fatigue life of the transverse cross joint specimens is prolonged by about 1.05 times when the stress range is at 40. 0 MPa.
基金the National Natural Science Foundation of China(NO.51405229)the Natural Science Foundation of Jiangsu Province of China(Nos.BK20151470 and BK20130796)
文摘To get the movement mode and driving mechanism similar to human shoulder joint,a six degrees of freedom(DOF) serial-parallel bionic shoulder joint mechanism driven by pneumatic muscle actuators(PMAs)was designed.However,the structural parameters of the shoulder joint will affect various performances of the mechanism.To obtain the optimal structure parameters,the particle swarm optimization(PSO) was used.Besides,the mathematical expressions of indexes of rotation ranges,maximum bearing torque,discrete dexterity and muscle shrinkage of the bionic shoulder joint were established respectively to represent its many-sided characteristics.And the multi-objective optimization problem was transformed into a single-objective optimization problem by using the weighted-sum method.The normalization method and adaptive-weight method were used to determine each optimization index's weight coefficient;then the particle swarm optimization was used to optimize the integrated objective function of the bionic shoulder joint and the optimal solution was obtained.Compared with the average optimization generations and the optimal target values of many experiments,using adaptive-weight method to adjust weights of integrated objective function is better than using normalization method,which validates superiority of the adaptive-weight method.
基金supported by the National Natural Science Foundation of China (Nos. 51975553 and 51931009)IMR SYNL-T.S. Kê Research Fellowship。
文摘Strong metal/non-polar plastic dissimilar joints are highly demanded for the lightweight design in many fields,which,however,are rather challenging to achieve directly via welding.In this study,we designed a laser processing pretreatment on the Al alloy to create a deep porous Al surface structure,which was successfully joined to the polypropylene(PP) via friction spot welding.A maximum joint strength of29 MPa was achieved,the same as that of the base PP(i.e.the joint efficiency reached 100%),much larger than ever reported.The joining mechanism of the Al alloy and the PP was mainly attributed to the large mechanical interlocking effect between the laser processed Al porous structure and the re-solidified PP and the formation of chemical bond at the interface.The deep porous Al surface structure modified by laser processing largely changed the Al-PP reaction feature.The evidence of the C-O-Al chemical bond was first time found at the non-polar plastic/Al joint interface,which was the reaction result between the oxide on the Al alloy surface and thermal oxidization products of the PP during welding.This study provides a new way for enhancing metal-plastic joints via surface laser treatment techniques.
文摘The authors have treated 50 cases of frozen shoulder in recent years with electro-acupuncture and the elevation manipulation. The results were satisfactory and reported as follows.
文摘Friction stir welding (FSW) and stationary shoulder friction stir welding (SSFSW) were carried out for the butt joining of dissimilar AA2024-T3 and AA7050-T7651 aluminium alloys with thicknesses of 2 mm. A comparison between the two processes was performed by varying the welding speed while keeping the rotational speed constant, Through the analysis of the force and torque produced during welding and a simple analytical model, it was possible to show that in SSFSW there is more effective coupling with the tool and the heat produced is more efficiently distributed. This process decreases both the welding area and the diffusion at the interface of the two alloys compared with FSW. The minimum microhardness occurred at the advancing side (AS) at the interface between the thermo-mechanically affected zone (TMAZ) and the stir zone (SZ) in both processes, although the decrease was more gradual in SSFSW. This interface is also where all specimens failed for both welding technologies. An increase in tensile strength was measured in SSFSW compared with standard FSW. Furthermore, it was possible to establish the mechanical performance of the material in the fracture zone using digital image correlation.
文摘BACKGROUND Non-albicans Candida prosthetic joint infections (PJIs) are rare. Optimal treatment involves a two-stage revision surgery in combination with an antifungal agent. However, no clear guidelines have been developed regarding the agent or treatment duration. Hence, a broad range of antifungal and surgical treatments have been reported so far. AIM To clarify treatment of non-albicans Candida PJIs. METHODS A literature review of all existing non-albicans Candida PJIs cases through April 2018 was conducted. Information was extracted about demographics, comorbidities, responsible species, duration and type of antifungal treatment, type of surgical treatment, time between initial arthroplasty and symptom onset, time between symptom onset and definite diagnosis, outcome of the infection and follow-up. RESULTS A total of 83 cases, with a mean age of 66.3 years, were located. The causative yeast isolated in most cases was C. parapsilosis (45 cases;54.2%), followed by C. glabrata (18 cases;21.7%). The mean Charlson comorbidity index was 4.4 ± 1.5. The mean time from arthropalsty to symptom onset was 27.2 ± 43 mo, while the mean time from symptom onset to culture-confirmed diagnosis was 7.5 ± 12.5 mo. A two stage revision arthroplasty (TSRA), when compared to one stage revision arthroplasty, had a higher success rate (96% vs 73%, P = 0.023). Fluconazole was the preferred antifungal agent (59;71%), followed by amphotericin B (41;49.4%). CONCLUSION The combination of TSRA and administration of prolonged antifungal therapy after initial resection arthroplasty is suggested on the basis of limited data.
基金supported by the CNPC (China National Petroleum Corporation) Innovation Foundation under grant No.07E1015
文摘A pipeline steel X80 with welded joint was subjected to surface mechanical attrition treatment (SMAT). After SMAT, a nanostructure surface layer with an average grain size of about 10 nm was formed in the treated sample, and the fatigue limit of the welded joint was elevated by about 13% relative to the untreated joints. In the low and the high amplitude stress regimes, both fatigue strength and fatigue life were enhanced. Formation of the nanostructured surface layer played more important role in the enhanced fatigue behavior than that of residual stress induced by the SMAT.
文摘The dissimilar metals 1Crl8Ni9 and 16MnR are welded by shielded metal arc welding process using electrode A312. The corrosion experiments are carried out on welded joint samples, which is as-welded and post-weld heat treatment at 650 ℃, 750 ℃ and 850 ℃, for 2 h in 70% sodium hydroxide solution. EDS and X-ray diffraction analysis are carried out on the samples after corrosion. Average corrosion rate calculation and microhardness measurement are conducted on both as- welded and post-weld heat treatment samples. The results indicate that average corrosion rate of as-welded joint metal is smaller than that of post-weld heat treatment joint metal. Compared with that of post-weld heat treatment at 750 ℃ and 850 ℃ for 2 h, the average corrosion rate of welded joint after post-weld heat treatment at 650 ℃ for 2 h increases greatly.
基金Project(CXLX14-1098)supported by Jiangsu Province Postgraduate Scientific Research Innovation Program,China
文摘The surface of 1Cr5 Mo heat-resistant steel welding joint was processed with CO2 laser, and the corrosion behaviors before and after laser heat treatment(LHT) were investigated in the salt spray corrosion environments. The microstructures, phases, residual stresses and retained austenite content of 1Cr5 Mo steel welding joint before and after LHT were analyzed with optical microscope and X-ray diffraction, respectively. The cracking morphologies and chemical compositions of corrosion products after salt spray corrosion were analyzed with field emission scanning electron microscopy(FESEM) and energy disperse spectroscopy(EDS), respectively, the polarization curves were measured on a PS-268 A type electrochemical workstation, and the mechanism of corrosion resistance by LHT was investigated as well. The results show that the passive film of original sample is destroyed owing to the corrosive media penetrating into the subsurface, resulting in the redox reaction. The content of residual austenite in the surface and the self-corrosion potential are increased by LHT, which is contributed to improving the capability of salt spray corrosion resistance.
文摘With the development of an IT (Information Technology) society, the opportunity to use electronic devices, such as cell phones and personal computers, has increased. These electronic devices pro-vide many benefits to society. However, there have been a number of reports of electromagnetic hypersensitivity (EHS) related to the use of electronic devices. The symptoms of EHS may include headaches, fatigue, tinnitus, dizziness, memory loss, irregular heartbeat, and skin trouble. Since the pathogenic mechanism of such conditions is not yet clear, further research is required. This report shows how a subject’s dizziness and joint mobility disorder, caused by electromagnetic waves emitted by electronic devices, were cured by removing an onlay from the patient’s mouth and replacing it with a gold alloy onlay. The result indicates that the subject’s symptoms were caused by EHS. Although the symptoms were improved after the dental treatment, the underlying mechanism of the symptoms and the reason why this treatment is successful remain unclear. Further research is required to clarify these issues.
文摘BACKGROUND Condylar osteophytes,a remodeling form of temporomandibular joint osteoarthritis(TMJ OA),mainly manifest as marginal angular outgrowths of the condyle.Previous researchers have advocated surgical removal of condylar osteophytes.Reports on the effect of occlusal splint on TMJ OA patients’joints have mostly focused on treatment with this splint,which can reduce the absorption of the affected condyle and promote repair and regeneration.However,the effect of the splint on the dissolution of condylar osteophytes has not yet been reported.CASE SUMMARY A 68-year-old female patient suffered from occlusal discomfort with left facial pain for 2 years.Cone beam computed tomography showed a rare osteophyte on top of her left condyle.She was finally diagnosed with TMJ OA.The patient refused surgical treatment and received conservative treatment with a muscle balance occlusal splint.The pain experienced by the patient on the left side of her face was relieved,and her chewing ability recovered after treatment.The osteophyte dissolved,and the condylar cortex remained stable during long-term follow-up observations.CONCLUSION The muscle balance occlusal splint could be a noninvasive means of treating condylar osteophytes in TMJ OA patients.
基金Funded by the National Natural Science Foundation of China(Nos.51505322,51175364)Natural Science Foundation of Shanxi Province of China(No.2013011014-3)
文摘Tungsten inert gas(TIG) welding was performed on 2.7 mm thick commercial extruded AZ31 B magnesium alloy plates. We investigated the effect of post-weld heat treatment(PWHT) on the microstructure, mechanical properties and precipitated phase of the weld joints. The results showed that during the annealing treatment(200 ℃-1 h, 250 ℃-1 h, 300 ℃-1 h, 350 ℃-1 h, 400 ℃-1 h, and 450 ℃-1 h), the average grain size in the weld seam was the minimum after annealing at 400 ℃ for 1 hour, and then abnormally grew up after annealing at 450 ℃ for 1 hour. The mechanical properties enhanced when the joints were processed from 200 ℃-1 h to 400 ℃-1 h but sharply decreased with increasing annealing temperature. In contrast to the annealing treatment, solution treatment(250 ℃-10 h, 300 ℃-10 h, 350 ℃-10 h, 400 ℃-10 h, and 450 ℃-10 h) exhibited a better ductility but a slight deterioration in tensile strength. Especially speaking, no eutectic compounds(such as Mg17 Al12) were observed in the weld seam. The supersaturated Al atoms were precipitated in a coarse spherical shape dispersed in the weld seam. The precipitated Al atoms dissolved in the matrix substances at the condition(400 ℃-1 h) or(250 ℃-10 h). The solution treatment caused grain coarsening and precipitated Al atoms dissolved in the weld seam substantially, which resulted in a drop in micro-hardness at the weld seam compared to the area of the annealed joints.
基金financially supported by the National Natural Science Foundation of China(No.51365014)the Industrial Support Key Project of Jiangxi Province,China(No.20161BBE50072)
文摘Improvement of the fatigue life of welded tubular T-joints in offshore platforms due to weld toe grinding and TIG dressing is studied physically and experimentally. It is shown that the two methods of treatment can improve the fatigue strength of welded tubular joints not only in the environment of air but even in the envirnment of seawater accordingly.
文摘The electron beam local post-weld heat treatment (EBLPWHT) is a rather new method that provides the advantages of high precision, flexibility and efficiency, energy saving and higher productivity. This paper studies the effect of two post-weld heat treatment processes on the microstructure, mechanical properties and fracture toughness of an electron beam welded joints in 30CrMnSiNi2A steel. EBLPWHT, in a vacuum chamber, immediately after welding and a traditional furnace whole post-weld heat treatment (FWPWHT) were compared. The experimental results show that, after EBLPWHT treatment, the main microstructure of weld was changed from coarse acicular martensite into lath martensite, HAZ was changed from lath martensite, bainite into lower bainite, and base metal was changed from ferrite and pearlite into upper bainite and residual austenite. The microstructures of different zones of joints in FWPWHT condition were tempered sorbite. The properties of welded joints can be improved by the EBLPWHT in some extent, and especially largely for the fracture toughness of welded joints. However the value of fracture toughness of base metal is comparatively low, so appropriate heat treatment parameters should be explored in the future.
基金financially supported by the Project of National Science & Technology Pillar Program (Nos.2009BAG12A07-B02 and 2009BAE80B01)National Natural Science Foundation of China (No.51071040)
文摘In this study, 3-mm-thick hot-extruded plates of A1-12.7Si-0.7Mg alloy were used to fabricate the joints welded by gas metal arc welding. Effects of the post-weld heat treatment include solid solution treatment, water quenching, and artificial aging treatment on the microstructure, and mechanical properties of the weld joints have been investigated. Results showed that the welded joints after solid solution and artificial aging exhibited the increases in yield strength of 166 MPa and ultimate tensile strength of 148 MPa, respectively. Based on the microstructural observations, the associated mechanisms were discussed.
文摘AIM To evaluate the joint geometry and the clinical outcome of stemless,anatomical shoulder arthroplasty with the TESS system.METHODS Twenty-one shoulders with a mean follow-up 18 of months were included.On scaled digital radiographs the premorbid center of rotation(CoR)was assessed and compared to the CoR of the prosthesis by using the MediC AD~?software.Additionally,the pre-and post-operative geometry of the CoR was assessed in relation to the glenoid,the acromion as well as to the proximal humerus.Radiological changes,such as radiolucencies,were also assessed.Clinical outcome was assessed with the Constant and DASH score.RESULTS Both,the Constant and DASH scores improved signifi-cantly from 11%to 75%and from 70 to 30 points,P<0.01 respectively.There were no significant differences regarding age,etiology,cemented or metal-backed glenoids,etc.(P>0.05).The pre-and postoperative humeral offset,the lateral glenohumeral offset,the height of the CoR,the acromiohumeral distance as well as neckshaft angle showed no significant changes(P>0.05).The mean deviation of the CoR of the prosthesis from the anatomic center was 1.0±2.8 mm.Three cases showed a medial deviation of more than 3 mm.These deviations of 5.1,5.7 and 7.6 mm and were caused by an inaccurate humeral neck cut.These 3 patients showed a relatively poor outcome scoring.CONCLUSION TESS arthroplasty allows an anatomical joint reconstruction with a very good outcome.Outliers described in this study sensitize the surgeon for an accurate humeral neck cut.