制药行业在严格的监管标准下运作,以确保无菌药品的安全性和质量。欧盟良好生产规范(EU GMP)附录1要求基于科学评估制定污染控制策略(Contamination Control Strategy,CCS),以理解工艺并应用风险管理原则。污染控制的一个重要方面是物...制药行业在严格的监管标准下运作,以确保无菌药品的安全性和质量。欧盟良好生产规范(EU GMP)附录1要求基于科学评估制定污染控制策略(Contamination Control Strategy,CCS),以理解工艺并应用风险管理原则。污染控制的一个重要方面是物料的转移,特别是进入A级区域。本文探讨了独立快速净化站(Rapid Decontamination Stations,RDS)在污染控制中的作用,并描述了使用RDS对物料进行去污并将其转移到灌装线隔离器中的过程。此外,还提供了从制造应用中获得的见解,涉及物料进出灌装隔离器的转移。RDS符合不断发展的监管标准,优化的装载配置和严格的循环设计标准确保了有效的净化。自动化控制确保了无菌性,从而实现安全高效的物料转移。展开更多
This study investigated the effects of weathering depth and thickness on the failure mechanisms of rock samples through experimental and numerical methods.The first configuration involved conducting artificial weather...This study investigated the effects of weathering depth and thickness on the failure mechanisms of rock samples through experimental and numerical methods.The first configuration involved conducting artificial weathering on limestone using the freezing and thawing(F-T)for 40 cycles.The mechanical parameters of the samples were measured at the end of the 40th cycle.In the second configuration,a series of specimens underwent salt crystallization(S-C)tests for 20 cycles.Experimental results were validated using discrete element method(DEM).Next,the weathered limestone model with dimensions of 108 mm54 mm were prepared.The weathering layers were tested at four different thicknesses(i.e.2.5 mm,5 mm,7.5 mm,and 10 mm)and three different positions(at the surface,5 mm under the rock surface,and 10 mm under the rock surface).According to the results,weathering depth and thickness have a considerable effect on the failure process.The results also showed a correlation between the values of compressive strength and failure mechanisms associated with the weathering layer.The numerical results revealed that the tension crack was the dominant factor.Additionally,with increasing weathering thickness,Young's modulus,crack initiation stress,and final strength decreased in constant weathering depth.The results also demonstrated that the failure progress of the numerical models was similar to that observed in the laboratory.展开更多
A severe spinal cord involvement may rarely occur in patients with cirrhosis and other chronic liver diseases;this complication is usually associated with overt liver failure and surgical or spontaneous porto-systemic...A severe spinal cord involvement may rarely occur in patients with cirrhosis and other chronic liver diseases;this complication is usually associated with overt liver failure and surgical or spontaneous porto-systemic shunt.Hepatic myelopathy(HM)is characterized by progressive weakness and spasticity of the lower extremities,while sensory and sphincter disturbances have rarely been described and are usually less important.The diagnosis is assigned in the appropriate clinical setting on clinical grounds after the exclusion of other clinical entities leading to spastic paraparesis.Magnetic resonance imaging is often unremarkable;however,also intracerebral corticospinal tract abnor-malities have been reported recently.The study of motor evoked potentials may disclose central conduction abnormalities even before HM is clinically manifest.HM responds poorly to blood ammonia-lowering and other conservative medical therapy.Liver transplantation represents a potentially definitive treatment for HM in patients with decompensated cirrhosis of Child-Pugh B and C grades.Other surgical treatment options in HM include surgical ligation,shunt reduction,or occlusion by interventional procedures.展开更多
Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment a...Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment at a nicotine exposure corresponding to that of an average European smoker. 63 male Fischer344 rats were randomized in three consecutive experiments of 21 animals each （A/B/C） to 3 experimental groups （7 rats, 112/3）. （A） cone-beam-computed tomography （CBCT）; （B） histology/serology; （C） reverse- transcription quantitative real-time polymerase chain reaction （RT-qPCR）/cotinine serology--（1） control; （2） orthodontic tooth movement （OTM） of the first and second upper left molar （NiTi closed coil spring, 0.25 N）; （3） OTM with 1.89 mg-kg- 1 per day s.c. of L（- ）-nicotine. After 14 days of OTM, serum cotinine and IL-6 concentration as well as orthodontically induced inflammatory root resorption （OIIRR）, osteoclast activity （histology）, orthodontic tooth movement velocity （CBCT, within 14 and 28 days of OTM） and relative gene expression of known inflammatory and osteoclast markers were quantified in the dental-periodontal tissue （RT-qPCR）. Animals exposed to nicotine showed significantly heightened serum cotinine and IL-6 levels corresponding to those of regular European smokers. Both the extent of root resorption, osteoclast activity, orthodontic tooth movement and gene expression of inflammatory and osteoclast markers were significantly increased compared to controls with and without OTM under the influence of nicotine. We conclude that apart from increased periodontal bone loss, a progression of dental root resorption and accelerated orthodontic tooth movement are to be anticipated during orthodontic therapy, if nicotine consumption is present. Thus patients should be informed about these risks and the necessity of nicotine abstinence during treatment.展开更多
本文发展了一种氮掺杂稻壳基多孔炭(N-RHPC)的制备方法,即将RHPC在氨气氛围下进行高温处理,操作简单,有利于大规模制备。结果表明,N-RHPC的介孔体积、石墨化程度明显提高,XPS N 1s谱证实了N原子在RHPC结构上的有效掺杂。N-RHPC作为ORR...本文发展了一种氮掺杂稻壳基多孔炭(N-RHPC)的制备方法,即将RHPC在氨气氛围下进行高温处理,操作简单,有利于大规模制备。结果表明,N-RHPC的介孔体积、石墨化程度明显提高,XPS N 1s谱证实了N原子在RHPC结构上的有效掺杂。N-RHPC作为ORR电催化剂具有与商用Pt/C接近的电催化活性,并具有较好的稳定性以及耐甲醇毒性,这主要是由于氨气氛围下对RHPC的高温处理使N原子进入RHPC中而引入了大量的催化位点所致。N-RHPC制备方法简单,性价比高,作为电催化剂具有很好的应用前景。展开更多
Superior ballistic performance and the lightweight character of Ti alloys are considered as main reasons for their use in armour applications against a broad spectrum of ballistic threats,e.g.bullet,fragment or blast ...Superior ballistic performance and the lightweight character of Ti alloys are considered as main reasons for their use in armour applications against a broad spectrum of ballistic threats,e.g.bullet,fragment or blast impact.Because dynamic loading caused by typical penetrators is characterized by high strain rates,only specific test methods allow a closer investigation of the respective material behaviour.In the present study,quasi-static and dynamic compression tests as well as ballistic tests were conducted on a twophase a+βalloy Ti-6Al-4V(in m%)manufactured by hot-rolling.Post-deformation heat treatments,influencing microstructure and mechanical properties were applied in order to compare three different microstructural configurations:as-rolled,mill-annealed and bimodal.While,on the one hand,ballistic tests were employed for the determination of the ballistic limit velocity v_(50),compression tests,on the other hand,delivered essential input parameters for the application of the Johnson-Cook constitutive model in a finite element simulation of the impact event.The comparison of experimental results to simulation results was supplemented by means of microstructural characterization of tested samples with the focus set on the prevalently observed deformation and damage mechanisms,as for example adiabatic shearing.展开更多
The ability of the adult central nervous system to reorganize its circuits over time is the key to understand the functional improvement in subjects with spinal cord injury （SCI）. Adaptive changes within spared neur...The ability of the adult central nervous system to reorganize its circuits over time is the key to understand the functional improvement in subjects with spinal cord injury （SCI）. Adaptive changes within spared neuronal circuits may occur at cortical, brainstem, or spinal cord level, both above and below a spinal lesion （Bareyre et al., 2004）. At each level the reorganization is a very dynamic process, and its degree is highly variable, depending on several factors, including the age of the subject when SCI has occurred and the rehabilitative therapy. The use of electrophysiological techniques to assess these functional changes in neural networks is of great interest, because invasive methodologies as employed in preclinical models can obviously not be used in clinical studies.展开更多
In recent years,wire-arc directed energy deposition(wa DED),which is also commonly known as wire-arc additive manufacturing(WAAM),has emerged as a promising new fabrication technique for magnesium alloys.The major rea...In recent years,wire-arc directed energy deposition(wa DED),which is also commonly known as wire-arc additive manufacturing(WAAM),has emerged as a promising new fabrication technique for magnesium alloys.The major reason for this is the possibility of producing parts with a complex geometry as well as a fine-grained microstructure.While the process has been shown to be applicable for Mg-Al-Zn alloys,there is still a lack of knowledge in terms of the influence of the WAAM process on the age-hardening response.Consequently,this study deals with the aging response of a WAAM AZ91 alloy.In order to fully understand the mechanisms during aging,first,the as-built condition was analyzed by means of high-energy X-ray diffraction(HEXRD)and scanning electron microscopy.These investigations revealed a finegrained,equiaxed microstructure with adjacent areas of alternating Al content.Subsequently,the difference between single-and double-step aging as well as conventional and direct aging was studied on the as-built WAAM AZ91 alloy for the first time.The aging response during the various heat treatments was monitored via in situ HEXRD experiments.Corroborating electron microscopy and hardness studies were conducted.The results showed that the application of a double-step aging heat treatment at 325℃with pre-aging at 250℃slightly improves the mechanical properties when compared to the single-step heat treatment at 325℃.However,the hardness decreases considerably after the pre-aging step.Thus,aging at lower temperatures is preferable within the investigated temperature range of 250-325℃.Moreover,no significant difference between the conventionally aged and directly aged samples was found.Lastly,the specimens showed enhanced precipitation kinetics during aging as compared to cast samples.This could be attributed to a higher amount of nucleation sites and the particular temperature profile of the solution heat treatment.展开更多
Does a post-lesional rewiring exist in the central nervous system （CNS）？ Whereas neuroimaging and neuromodulation techniques illustrate the extensive cortical reshaping after a brain injury, the remodeling of ascen...Does a post-lesional rewiring exist in the central nervous system （CNS）？ Whereas neuroimaging and neuromodulation techniques illustrate the extensive cortical reshaping after a brain injury, the remodeling of ascending and descending neuronal pathway is more difficult to be investigated. Here, we discuss how the studies dealing with hemispherectomy （HS） can provide interesting information about the functional and anatomical reorganization which take place after an extensive unilateral lesion. Indeed, studies in humans and animal models of HS clearly illustrate that the brain is capable of a widespread rewiring between the contralesional cortices and the subcortical structures as well as the medullary segments linked to the affected side of the body.展开更多
Polycrystalline zinc oxide (ZnO) thin films have been deposited at 450°C onto glass and silicon substrates by pulsed laser deposition technique (PLD). The used source was a KrF excimer laser (248 nm, 25 ns, 5 Hz,...Polycrystalline zinc oxide (ZnO) thin films have been deposited at 450°C onto glass and silicon substrates by pulsed laser deposition technique (PLD). The used source was a KrF excimer laser (248 nm, 25 ns, 5 Hz, 2 J/cm2). The effects of glass and silicon substrates on structural and optical properties of ZnO films have been investigated. X-ray diffraction patterns showed that ZnO films are polycrystalline with a hexagonal wurtzite—type structure with a strong (103) orientation and have a good crystallinity on monocrystalline Si(100) substrate. The thickness and compositional depth profile were studied by Rutherford Backscattering spectrometry (RBS). The average transmittance of ZnO films deposited on glass substrate in the visible range is 70%.展开更多
A combination of both conventional and advanced high-resolution characterization techniques was applied to study the modified layers on the surface of three composite Al-Cr arc cathodes with identical nominal composit...A combination of both conventional and advanced high-resolution characterization techniques was applied to study the modified layers on the surface of three composite Al-Cr arc cathodes with identical nominal composition of Al-50 at.%Cr but varying powder grain sizes.The results revealed that the modified layers consist mainly of metastable phases such as Cr solid solution,high temperature cubic Al8 Cr5,supersaturated Al solid solution,and icosahedral quasicrystal.The metastable phase formation indicates that high cooling rates were involved during the solidification of molten material produced in the arc craters during cathode spot events.The average cooling rate was estimated to be 10^(6)K/s based on secondary dendrite arm spacing measurements and supporting phase-field based simulations.The formation mechanisms of the modified layers are discussed based on the obtained results and the current literature.展开更多
Transcranial magnetic stimulation（TMS）represents a useful non-invasive approach to studying cortical physiology,in addition to the descending motor pathways（Hallett,2000）,and may also be used to investigate the in...Transcranial magnetic stimulation（TMS）represents a useful non-invasive approach to studying cortical physiology,in addition to the descending motor pathways（Hallett,2000）,and may also be used to investigate the intracortical facilitatory and inhibitory mechanisms.展开更多
要独步就要唯一,要独步就要创新!中国许多民间美术工艺不但工艺高超,更具有非凡的创意设计,这些工艺设计同时是最 Local 的魅力。东方有着深厚的文化和美学底蕴,而位于东方的中国不但拥有这些,还有享誉全世界的瓷器,从某种程度来说,全...要独步就要唯一,要独步就要创新!中国许多民间美术工艺不但工艺高超,更具有非凡的创意设计,这些工艺设计同时是最 Local 的魅力。东方有着深厚的文化和美学底蕴,而位于东方的中国不但拥有这些,还有享誉全世界的瓷器,从某种程度来说,全世界的人们都应该感谢中国人发明了纯洁、完美又优雅无比的瓷器。展开更多
The role of the ipsilaterally descending motor pathways in the recovery mechanisms after unilateral hemispheric damage is still poorly understood. Motor output reorganization was investigated in a 56-year-old male pat...The role of the ipsilaterally descending motor pathways in the recovery mechanisms after unilateral hemispheric damage is still poorly understood. Motor output reorganization was investigated in a 56-year-old male patient with acquired unilateral hemispheric atrophy due to Rasmussen encephalitis. In particular,the ipsilateral corticospinal pathways were explored using focal transcranial magnetic stimulation. In the first dorsal interosseous and wrist extensors muscles, the median amplitudes of the ipsilateral motor evoked potentials induced by transcranial magnetic stimulation in the patient were higher than those of 10 age-matched healthy control subjects. In the biceps brachii muscle, the median amplitudes of the ipsilateral motor evoked potentials were the second largest in the patient compared to the controls. This study demonstrated a reinforcement of ipsilateral motor projections from the unaffected motor cortex to the hemiparetic hand in a subject with acquired unihemispheric cortical damage.展开更多
文摘This study investigated the effects of weathering depth and thickness on the failure mechanisms of rock samples through experimental and numerical methods.The first configuration involved conducting artificial weathering on limestone using the freezing and thawing(F-T)for 40 cycles.The mechanical parameters of the samples were measured at the end of the 40th cycle.In the second configuration,a series of specimens underwent salt crystallization(S-C)tests for 20 cycles.Experimental results were validated using discrete element method(DEM).Next,the weathered limestone model with dimensions of 108 mm54 mm were prepared.The weathering layers were tested at four different thicknesses(i.e.2.5 mm,5 mm,7.5 mm,and 10 mm)and three different positions(at the surface,5 mm under the rock surface,and 10 mm under the rock surface).According to the results,weathering depth and thickness have a considerable effect on the failure process.The results also showed a correlation between the values of compressive strength and failure mechanisms associated with the weathering layer.The numerical results revealed that the tension crack was the dominant factor.Additionally,with increasing weathering thickness,Young's modulus,crack initiation stress,and final strength decreased in constant weathering depth.The results also demonstrated that the failure progress of the numerical models was similar to that observed in the laboratory.
文摘A severe spinal cord involvement may rarely occur in patients with cirrhosis and other chronic liver diseases;this complication is usually associated with overt liver failure and surgical or spontaneous porto-systemic shunt.Hepatic myelopathy(HM)is characterized by progressive weakness and spasticity of the lower extremities,while sensory and sphincter disturbances have rarely been described and are usually less important.The diagnosis is assigned in the appropriate clinical setting on clinical grounds after the exclusion of other clinical entities leading to spastic paraparesis.Magnetic resonance imaging is often unremarkable;however,also intracerebral corticospinal tract abnor-malities have been reported recently.The study of motor evoked potentials may disclose central conduction abnormalities even before HM is clinically manifest.HM responds poorly to blood ammonia-lowering and other conservative medical therapy.Liver transplantation represents a potentially definitive treatment for HM in patients with decompensated cirrhosis of Child-Pugh B and C grades.Other surgical treatment options in HM include surgical ligation,shunt reduction,or occlusion by interventional procedures.
基金the ReForM-A-research funding programme of the Faculty of Medicine(University of Regensburg)for their financial supportsupported by a ReForM-A grant from the ReForM research funding programme of the Faculty of Medicine of the University of Regensburg,Germany(Kirschneck 31 March 2015)the German Research Foundation(DFG)within the funding programme Open Access Publishing
文摘Orthodontic forces have been reported to significantly increase nicotine-induced periodontal bone loss. At present, however, it is unknown, which further （side） effects can be expected during orthodontic treatment at a nicotine exposure corresponding to that of an average European smoker. 63 male Fischer344 rats were randomized in three consecutive experiments of 21 animals each （A/B/C） to 3 experimental groups （7 rats, 112/3）. （A） cone-beam-computed tomography （CBCT）; （B） histology/serology; （C） reverse- transcription quantitative real-time polymerase chain reaction （RT-qPCR）/cotinine serology--（1） control; （2） orthodontic tooth movement （OTM） of the first and second upper left molar （NiTi closed coil spring, 0.25 N）; （3） OTM with 1.89 mg-kg- 1 per day s.c. of L（- ）-nicotine. After 14 days of OTM, serum cotinine and IL-6 concentration as well as orthodontically induced inflammatory root resorption （OIIRR）, osteoclast activity （histology）, orthodontic tooth movement velocity （CBCT, within 14 and 28 days of OTM） and relative gene expression of known inflammatory and osteoclast markers were quantified in the dental-periodontal tissue （RT-qPCR）. Animals exposed to nicotine showed significantly heightened serum cotinine and IL-6 levels corresponding to those of regular European smokers. Both the extent of root resorption, osteoclast activity, orthodontic tooth movement and gene expression of inflammatory and osteoclast markers were significantly increased compared to controls with and without OTM under the influence of nicotine. We conclude that apart from increased periodontal bone loss, a progression of dental root resorption and accelerated orthodontic tooth movement are to be anticipated during orthodontic therapy, if nicotine consumption is present. Thus patients should be informed about these risks and the necessity of nicotine abstinence during treatment.
文摘本文发展了一种氮掺杂稻壳基多孔炭(N-RHPC)的制备方法,即将RHPC在氨气氛围下进行高温处理,操作简单,有利于大规模制备。结果表明,N-RHPC的介孔体积、石墨化程度明显提高,XPS N 1s谱证实了N原子在RHPC结构上的有效掺杂。N-RHPC作为ORR电催化剂具有与商用Pt/C接近的电催化活性,并具有较好的稳定性以及耐甲醇毒性,这主要是由于氨气氛围下对RHPC的高温处理使N原子进入RHPC中而引入了大量的催化位点所致。N-RHPC制备方法简单,性价比高,作为电催化剂具有很好的应用前景。
文摘Superior ballistic performance and the lightweight character of Ti alloys are considered as main reasons for their use in armour applications against a broad spectrum of ballistic threats,e.g.bullet,fragment or blast impact.Because dynamic loading caused by typical penetrators is characterized by high strain rates,only specific test methods allow a closer investigation of the respective material behaviour.In the present study,quasi-static and dynamic compression tests as well as ballistic tests were conducted on a twophase a+βalloy Ti-6Al-4V(in m%)manufactured by hot-rolling.Post-deformation heat treatments,influencing microstructure and mechanical properties were applied in order to compare three different microstructural configurations:as-rolled,mill-annealed and bimodal.While,on the one hand,ballistic tests were employed for the determination of the ballistic limit velocity v_(50),compression tests,on the other hand,delivered essential input parameters for the application of the Johnson-Cook constitutive model in a finite element simulation of the impact event.The comparison of experimental results to simulation results was supplemented by means of microstructural characterization of tested samples with the focus set on the prevalently observed deformation and damage mechanisms,as for example adiabatic shearing.
文摘The ability of the adult central nervous system to reorganize its circuits over time is the key to understand the functional improvement in subjects with spinal cord injury （SCI）. Adaptive changes within spared neuronal circuits may occur at cortical, brainstem, or spinal cord level, both above and below a spinal lesion （Bareyre et al., 2004）. At each level the reorganization is a very dynamic process, and its degree is highly variable, depending on several factors, including the age of the subject when SCI has occurred and the rehabilitative therapy. The use of electrophysiological techniques to assess these functional changes in neural networks is of great interest, because invasive methodologies as employed in preclinical models can obviously not be used in clinical studies.
基金supported by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020the financial support of the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Grant No.771146 TOUGHIT)funded within the AIT’s strategic research portfolio 2022 and by the European Commission within the framework INTERREG V-A Austria–Czech Republic in the project“ReMaP“(Interreg project no.ATCZ229)。
文摘In recent years,wire-arc directed energy deposition(wa DED),which is also commonly known as wire-arc additive manufacturing(WAAM),has emerged as a promising new fabrication technique for magnesium alloys.The major reason for this is the possibility of producing parts with a complex geometry as well as a fine-grained microstructure.While the process has been shown to be applicable for Mg-Al-Zn alloys,there is still a lack of knowledge in terms of the influence of the WAAM process on the age-hardening response.Consequently,this study deals with the aging response of a WAAM AZ91 alloy.In order to fully understand the mechanisms during aging,first,the as-built condition was analyzed by means of high-energy X-ray diffraction(HEXRD)and scanning electron microscopy.These investigations revealed a finegrained,equiaxed microstructure with adjacent areas of alternating Al content.Subsequently,the difference between single-and double-step aging as well as conventional and direct aging was studied on the as-built WAAM AZ91 alloy for the first time.The aging response during the various heat treatments was monitored via in situ HEXRD experiments.Corroborating electron microscopy and hardness studies were conducted.The results showed that the application of a double-step aging heat treatment at 325℃with pre-aging at 250℃slightly improves the mechanical properties when compared to the single-step heat treatment at 325℃.However,the hardness decreases considerably after the pre-aging step.Thus,aging at lower temperatures is preferable within the investigated temperature range of 250-325℃.Moreover,no significant difference between the conventionally aged and directly aged samples was found.Lastly,the specimens showed enhanced precipitation kinetics during aging as compared to cast samples.This could be attributed to a higher amount of nucleation sites and the particular temperature profile of the solution heat treatment.
文摘Does a post-lesional rewiring exist in the central nervous system （CNS）？ Whereas neuroimaging and neuromodulation techniques illustrate the extensive cortical reshaping after a brain injury, the remodeling of ascending and descending neuronal pathway is more difficult to be investigated. Here, we discuss how the studies dealing with hemispherectomy （HS） can provide interesting information about the functional and anatomical reorganization which take place after an extensive unilateral lesion. Indeed, studies in humans and animal models of HS clearly illustrate that the brain is capable of a widespread rewiring between the contralesional cortices and the subcortical structures as well as the medullary segments linked to the affected side of the body.
文摘Polycrystalline zinc oxide (ZnO) thin films have been deposited at 450°C onto glass and silicon substrates by pulsed laser deposition technique (PLD). The used source was a KrF excimer laser (248 nm, 25 ns, 5 Hz, 2 J/cm2). The effects of glass and silicon substrates on structural and optical properties of ZnO films have been investigated. X-ray diffraction patterns showed that ZnO films are polycrystalline with a hexagonal wurtzite—type structure with a strong (103) orientation and have a good crystallinity on monocrystalline Si(100) substrate. The thickness and compositional depth profile were studied by Rutherford Backscattering spectrometry (RBS). The average transmittance of ZnO films deposited on glass substrate in the visible range is 70%.
基金Financial support by the Osterreichische Forschungs forderungsgesellschaft mb H(FFG)within the framework of the project“Arc Cathode Erosion”(Project No.856889)。
文摘A combination of both conventional and advanced high-resolution characterization techniques was applied to study the modified layers on the surface of three composite Al-Cr arc cathodes with identical nominal composition of Al-50 at.%Cr but varying powder grain sizes.The results revealed that the modified layers consist mainly of metastable phases such as Cr solid solution,high temperature cubic Al8 Cr5,supersaturated Al solid solution,and icosahedral quasicrystal.The metastable phase formation indicates that high cooling rates were involved during the solidification of molten material produced in the arc craters during cathode spot events.The average cooling rate was estimated to be 10^(6)K/s based on secondary dendrite arm spacing measurements and supporting phase-field based simulations.The formation mechanisms of the modified layers are discussed based on the obtained results and the current literature.
文摘Transcranial magnetic stimulation（TMS）represents a useful non-invasive approach to studying cortical physiology,in addition to the descending motor pathways（Hallett,2000）,and may also be used to investigate the intracortical facilitatory and inhibitory mechanisms.
文摘The role of the ipsilaterally descending motor pathways in the recovery mechanisms after unilateral hemispheric damage is still poorly understood. Motor output reorganization was investigated in a 56-year-old male patient with acquired unilateral hemispheric atrophy due to Rasmussen encephalitis. In particular,the ipsilateral corticospinal pathways were explored using focal transcranial magnetic stimulation. In the first dorsal interosseous and wrist extensors muscles, the median amplitudes of the ipsilateral motor evoked potentials induced by transcranial magnetic stimulation in the patient were higher than those of 10 age-matched healthy control subjects. In the biceps brachii muscle, the median amplitudes of the ipsilateral motor evoked potentials were the second largest in the patient compared to the controls. This study demonstrated a reinforcement of ipsilateral motor projections from the unaffected motor cortex to the hemiparetic hand in a subject with acquired unihemispheric cortical damage.
