In order to solve the difficult conditions of soft rock,water-trickling and hard-maintain of main air-return roadway in Tarangaole Colliery,high pretensioned stress and intensive bolt-shotcrete support program was des...In order to solve the difficult conditions of soft rock,water-trickling and hard-maintain of main air-return roadway in Tarangaole Colliery,high pretensioned stress and intensive bolt-shotcrete support program was designed and mechanical property of shotcrete layer was specially monitored through utilizing a type of concrete stress meter with oscillating chord after the program was carried out.It was indicated that,due to rock pressure and support resistance,the interior of shotcrete layer would emerge diverse stresses in axial,radial and tangential directions.With time passing internal stresses in three directions,whose average values were-0.061,0.043 and 0.517 MPa respectively,fluctuated first and then tended to stability slowly.The axial and radial stresses were relatively smaller than tangential stress which was 11,12 times the two formers respectively.Along the section of roadway,axial and tangential stresses distributed symmetrically and increased gradually from the top of arch to the waist of wall,but reduced at the foot of wall.Radial stresses reduced from the top of arch to the waist of arch first,and then increased in the waist of wall.Axial stresses were tensile substantially,except for stresses in arch vault tending to compressive,but all the radial stresses were compressive.Nevertheless,tangential stresses in the wall were compressive and tangential stresses in the arch were tensile.During the period of roadway excavating,the stress of shotcrete layer was less than its ultimate bearing capacity,with no significant stress concentration.At the end of this article,some suggests are given to shotcrete support design.展开更多
There is less research on vertical sculptured grinding technology. Especially in high vertical surface grinding process with the cup abrasive wheel, the thermal damage is prone to happen and undermine the grinding sur...There is less research on vertical sculptured grinding technology. Especially in high vertical surface grinding process with the cup abrasive wheel, the thermal damage is prone to happen and undermine the grinding surface integrity. This problem limits to improve the grinding efficiency and the grinding ratio greatly. Through the analysis of vertical surface grinding process and features in depth, this paper revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel. Based on the previous research achievements, the grinding experiments on TC4 (Ti-6A1-4V) and GH4169 are carried out utilizing the self-inhaling internal cooling wheel. The experimental results show that the self-inhaling internal cooling wheel can efficiently reduce the grinding surface temperature. Moreover, the inherent mechanism of reducing the grinding temperature using the internal cooling method is revealed. Meanwhile, under the same grinding conditions, the grinding ratio during the experiments on GH4169 using self-inhaling internal cooling method is about 3 times as high as using conventional external cooling method. And the grinding forces can be reduced by about 20%. This research revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel, which provides theoretical basis for the design and application of self-inhaling internal cooling wheel. At the same time, an efficient and non-invasive surface grinding method of TC4 and GH4169 is presented.展开更多
In this paper, iterative learning control (ILC) design is studied for an iteration-varying tracking problem in which reference trajectories are generated by high-order internal models (HOLM). An HOlM formulated as...In this paper, iterative learning control (ILC) design is studied for an iteration-varying tracking problem in which reference trajectories are generated by high-order internal models (HOLM). An HOlM formulated as a polynomial operator between consecutive iterations describes the changes of desired trajectories in the iteration domain and makes the iterative learning problem become iteration varying. The classical ILC for tracking iteration-invariant reference trajectories, on the other hand, is a special case of HOlM where the polynomial renders to a unity coefficient or a special first-order internal model. By inserting the HOlM into P-type ILC, the tracking performance along the iteration axis is investigated for a class of continuous-time nonlinear systems. Time-weighted norm method is utilized to guarantee validity of proposed algorithm in a sense of data-driven control.展开更多
AIM:To assess the impact of macular surgery on the functional and anatomic outcomes of the patients in different grades of epiretinal membrane(ERM).METHODS:Seventy-one eyes of 71 patients who underwent 23-gauge tr...AIM:To assess the impact of macular surgery on the functional and anatomic outcomes of the patients in different grades of epiretinal membrane(ERM).METHODS:Seventy-one eyes of 71 patients who underwent 23-gauge transconjunctival sutureless pars plana vitrectomy for primary isolated ERM were evaluated in this study.RESULTS:There were 38 females(53.5%) and 33 males(46.5%).The average age of the patients was 68.1 y(range 42-89 y).Mean follow up period was 14 mo(range 6-26 mo).The cases were divided into two subgroups of cellophane maculopathy(CM) and macular pucker(MP).An improvement was observed in the postoperative best-corrected visual acuity(BCVA),as well as a decrement in central foveal thickness(CFT) in both groups(both of these being statistically significant;P=0.001).In comparison between two groups,it was found that there was a significant improvement on BCVA and CFT in CM group than MP group(P=0.01).Furthermore,the postoperative fundus findings regarding RPE alterations and macular edema were significantly higher in MP group when compared to the CM group(P=0.01).CONCLUSION:ERM and internal limiting membrane peeling surgery can lead to a significant reduction of CFT and visual improvements in idiopathic ERM.A long-term ERM persistence will cause unrecoverable retinal damage and visual loss.展开更多
Internal bond (IB) strength is one of the most important me- chanical properties that indicate particleboard quality. The aim of this study was to find a simple regression model that considers the most important par...Internal bond (IB) strength is one of the most important me- chanical properties that indicate particleboard quality. The aim of this study was to find a simple regression model that considers the most important parameters that can influence on IB strength. In this study, IB strength was predicted by three kinds of equations (linear, quadratic, and exponential) that were based on the percentage of adhesive (8%, 9.5%, and 11%), particle size (+5, -5 +8, -8 12, and -12 mesh), and density (0.65, 0.7, and 0.75 g/cm3). Our analysis of the results (using SHAZAM 9 software) showed that the exponential function best fitted the experi- mental data and predicted the IB strength with 18~,/0 error. In order de- crease the error percentage, the Buckingham Pi theorem was used to build regression models for predicting IB strength based on particle size,展开更多
The present study observed hemodynamic changes in 26 patients with cerebral arteriosclerosis using a cerebral circulation dynamics detector and transcranial Doppler. In patients with cerebral arteriosclerosis the bloo...The present study observed hemodynamic changes in 26 patients with cerebral arteriosclerosis using a cerebral circulation dynamics detector and transcranial Doppler. In patients with cerebral arteriosclerosis the blood supply and flow rate in the bilateral carotid arteries and the blood flow rate in the anterior cerebral and middle cerebral arteries were similar to normal controls, but the cerebral vascular resistance, critical pressure and pulsatility index were increased, and cerebral arterial elasticity and cerebral blood flow autoregulation were decreased. Compared with the lesioned hemisphere of patients with cerebral infarction, the total blood supply and blood flow rate of patients with cerebral arteriosclerosis were higher. Compared with normal subjects, patients with cerebral arteriosclerosis exhibited cognitive disturbances, mainly in short-term memory, attention, abstract capability, and spatial and executive dysfunction. Results showed that cerebral arteriosclerosis does not directly affect the blood supply of a cerebral hemisphere, but affects cognitive function. The increased cerebral vascular resistance and reduced autoregulation of cerebral blood vessels may be important hemodynamic mechanisms of arteriosclerosis-induced cerebral infarction.展开更多
Objective: To construct recombinant adeno-associated virus co-expressing human vascular epithelial growth factor 165(hVEGF165) and bone morphogenetic protein 7(hBMPT), measure the virus titer and verify the recom...Objective: To construct recombinant adeno-associated virus co-expressing human vascular epithelial growth factor 165(hVEGF165) and bone morphogenetic protein 7(hBMPT), measure the virus titer and verify the recombination. Methods:The AAV helper-free system was used as basis to generate recombinant AAV. The IRES sequence of plasmid plRES was cut down and subcloned into ITR/ MCS containing vector pAAV-MCS to construct recombinant plasmid pAAV-MCSa-IRES-MCSb. The hVEGF165 and hBMP7 gene was amplified by PCR and inserted into upstream MCSa and downstream MCSb respectively. Then, recombinant plasmid pAAV- hVEGF165-IRES-hBMP7, pAAV-RC and pHelper were co-transfected into AAV-293 cells to complete rAAV-hVEGF165-IRES-hBMP7 packaging. The GFP labeled rAAV-IRES-GFP was simultaneously packaged by using the parallel plasmid pAAV-IRES-hrGFP. The efficiency of AAV packaging was monitored under fluorescent microscope and recombinant viral particles were harvested from infected AAV-293 cells. The virus titer was measured by infecting AAV-HT1080 cells, and the recombinant AAV-hVEGF165-IRES-hBMP7 was verified by PCR of the exogenous interest genes. Results:Recombinant pAAV-hVEGF165-IRES-hBMP7 was verified by double digestion. GFP expression in AAV-293 could be observed under fluorescent microscope 72 h after transfection and the system provided a high packing ratio of 95%. The recombinant adeno-associated virus has a high titer of 5.5 ×10^11vp/ml, and AAV-HT 1080 was infected at a ratio of 90%. The recombinant virus was confirmed by PCR of exogenous hBMP7 and hVEGF165 gene. Conclusion:Recombinant rAAV-hVEGF165-IRES-hBMP7 was successfully constructed with a high virus titer, which may offer foundation for in vitro and in vivo experiments of hVEGF165 and hBMP7 co-expression and provide a new method for gene therapy of bone regeneration.展开更多
在英语世界中,对jus gentium的翻译最初以保留其拉丁语形态为主。经过三次语义转移,罗马法对jus gentium赋予了更多的自然理性色彩,jus naturale也成了jus gentium的同义词之一。阿奎那的“ius inter gentes”(民族间法)和“ius inter o...在英语世界中,对jus gentium的翻译最初以保留其拉丁语形态为主。经过三次语义转移,罗马法对jus gentium赋予了更多的自然理性色彩,jus naturale也成了jus gentium的同义词之一。阿奎那的“ius inter gentes”(民族间法)和“ius inter omnes gentes”(全民族间法)推动“jus gentium”现代国际法内涵逐渐饱满,后来格劳秀斯将其基本确定为现代的“国际法”。边沁创制的“international law”一词至今仍存在争议,与“law of nations”并行使用的同时,“universal public law”(公法)、“transnational law”(跨国法)、“universal law”(普遍法)等术语均未能弱化“international law”的稳固地位。在中国,“international law”通过晚清政府的“各国律例”被降格为国内法,但也在一定程度上承认了各国的主体地位。日本未经转译等复杂的中间环节,将国际法支点术语“international law”创译为更贴近原作的“国际法”,精准地表现出了“国家之间的法”(interstate law)的内涵。展开更多
The astonishing surge in China's international trade is the result of comprehensive economic reforms in the 1980s and 1990s. Trade was further bolstered by China's accession to the World Trade Organization (WTO) i...The astonishing surge in China's international trade is the result of comprehensive economic reforms in the 1980s and 1990s. Trade was further bolstered by China's accession to the World Trade Organization (WTO) in 2001. We examine several aspects of China's international trade that might help to explain its surprisingly fast growth and its ever-growing role in the global economy. A large number of studies have analyzed how trade liberalization, the WTO accession in particular, has profoundly changed the Chinese economy. We survey notable contributions to this literature that analyze the effects of trade liberalization on Chinese firms, individuals and households. Meanwhile, China "s exports have had various effects on importing countries and the enormous growth of China's exports is seen by some observers as posing a threat to China "s trading partners. Therefore, we discuss the emerging literature on the effects of China "s spectacular export growth on consumers, labor markets, innovation, media and politics in foreign countries. Given the new domestic and external circumstances, the Chinese Government is determined to push for the formation of a new trade structure characterized by broad opening up to transform China into a strong trading powerhouse.展开更多
An examination of available data reveals large trade misinvoicing between China and its trade partners. The analysis finds a net trade misinvoicing of US$287.6bn between 2000 and 2005, while the full magnitude of unre...An examination of available data reveals large trade misinvoicing between China and its trade partners. The analysis finds a net trade misinvoicing of US$287.6bn between 2000 and 2005, while the full magnitude of unrecorded trade is estimated at US$1.4tn. China needs to establish more effective management of its international trade flows. At the same time, the international community needs to provide more effective governance mechanisms to address trade misinvoicing.展开更多
Using an internationally linked patent database, this paper compares the types of R &D activities undertaken by multinationals in China by home country and industry. In China, multinationals recently began investing ...Using an internationally linked patent database, this paper compares the types of R &D activities undertaken by multinationals in China by home country and industry. In China, multinationals recently began investing in R&D, mainly in the areas of product and manufacturing process development. However, US firms, which are the most actively invested in R&D, are involved in some technology-driven R&D activities; European firms are inclined toward market-driven R &D, while Japanese firms, which lag behind the other two, focus on production-driven R &D. This pattern may be related to the relative competitiveness of each country: Japanese firms are strong in electronics and automobiles, where production process improvement is important, while US firms flourish in science-based industries, such as pharmaceuticals and software, where interacting with the local science base is a critical factor.展开更多
The Lin-gang Special Area of the China(Shanghai)Pilot Free Trade Zone(FTZ)was off icially unveiled on August 20 after an overall plan was issued by the State Council on August 6.The special area is one of the measures...The Lin-gang Special Area of the China(Shanghai)Pilot Free Trade Zone(FTZ)was off icially unveiled on August 20 after an overall plan was issued by the State Council on August 6.The special area is one of the measures for advancing further opening up initiated by Chinese President Xi Jin ping at the First China International Import Expo in November 2018.展开更多
Interactions between an isolate of dark septate endophytes (DSE) and roots of Dendrobium nobile Lindl. seedlings are reported in this paper. The isolate was obtained from orchid mycorrhizas on Dendrobium sp. in subt...Interactions between an isolate of dark septate endophytes (DSE) and roots of Dendrobium nobile Lindl. seedlings are reported in this paper. The isolate was obtained from orchid mycorrhizas on Dendrobium sp. in subtropical forest. The fungus formed typical orchid mycorrhiza in aseptic co-culture with D. nobile seedlings on modified Murashige-Skoog (MMS) medium. Anatomic observations of the infected roots showed that the DSE hyphae invaded the velamen layer, passed through passage cells in exodermis, entered the cortex cells, and then formed fungal pelotons of orchid mycorrhiza. D. nobile seedlings' plant height, stem diameter, new roots number and biomass were greatly enhanced by inoculating the fungus to seedlings. The fungus was identified as Leptodontidium by sequencing the polymerase chain reaction-amplified rDNA ITS1-5,8S-ITS2 (internal transcribed spacer (ITS)) regions and comparison with similar taxa.展开更多
In this study, an analysis on the internal wave generation via the gravity collapse mechanism is carried out based on the theoretical formulation and the numerical simulation. With the linear theoretical model, a rect...In this study, an analysis on the internal wave generation via the gravity collapse mechanism is carried out based on the theoretical formulation and the numerical simulation. With the linear theoretical model, a rectangle shape wave is generated and propagates back and forth in the domain, while a two-dimensional non-hydrostatic numerical model could reproduce all the observed phenomena in the laboratory experiments conducted by Chen et al. (2007), and the related process realistically. The model results further provide more quantitative information in the whole domain, thus allowing an in depth understanding of the corresponding internal solitary wave generation and propagation. It is shown that the initial type of the internal wave is determined by the relative height between the perturbation and the environmental density interface, while the final wave type is related to the relative height of the upper and lower layers of the environmental fluid. The shape of the internal wave generated is consistent with that predicted by the KdV and EKdV theories if its amplitude is small, as the amplitude becomes larger, the performance of the EKdV becomes better after the wave adjusts itself to the ambient stratification and reaches an equilibrium state between the nonlinear and dispersion effects. The evolution of the mechanical energy is also analyzed.展开更多
Compared to single arm robot system, dual arm robot has the ability of performing human-like dexterity and cooperation. Dual arm cooperative operation has attracted more and more attention in industrial applications, ...Compared to single arm robot system, dual arm robot has the ability of performing human-like dexterity and cooperation. Dual arm cooperative operation has attracted more and more attention in industrial applications, such as in assembly of complex parts, manufacturing tasks and handling objects. A unified dynamic control method, which is divided into three modes, namely, independent mode, dependent mode, and half dependent mode, is proposed for a redundant dual arm robot with focus on the movement and force of the desired task being operated. Attention is devoted to develop a unified formulation of the above three modes. In addition, a closed form of inverse kinematic solution instead of numerical integration approach is proposed with the aim to guarantee position accuracy. Different from traditional dynamic controllers, where the independent redundancy resolution is obtained based on particular velocity or acceleration levels, here the two dynamic controllers are improved by combining a closed form of inverse kinematic solution with velocity and acceleration levels. Furthermore, the theoretical results of the proposed control method are validated by simulations and experiments.展开更多
文摘In order to solve the difficult conditions of soft rock,water-trickling and hard-maintain of main air-return roadway in Tarangaole Colliery,high pretensioned stress and intensive bolt-shotcrete support program was designed and mechanical property of shotcrete layer was specially monitored through utilizing a type of concrete stress meter with oscillating chord after the program was carried out.It was indicated that,due to rock pressure and support resistance,the interior of shotcrete layer would emerge diverse stresses in axial,radial and tangential directions.With time passing internal stresses in three directions,whose average values were-0.061,0.043 and 0.517 MPa respectively,fluctuated first and then tended to stability slowly.The axial and radial stresses were relatively smaller than tangential stress which was 11,12 times the two formers respectively.Along the section of roadway,axial and tangential stresses distributed symmetrically and increased gradually from the top of arch to the waist of wall,but reduced at the foot of wall.Radial stresses reduced from the top of arch to the waist of arch first,and then increased in the waist of wall.Axial stresses were tensile substantially,except for stresses in arch vault tending to compressive,but all the radial stresses were compressive.Nevertheless,tangential stresses in the wall were compressive and tangential stresses in the arch were tensile.During the period of roadway excavating,the stress of shotcrete layer was less than its ultimate bearing capacity,with no significant stress concentration.At the end of this article,some suggests are given to shotcrete support design.
基金supported by National Natural Science Foundation of China(Grant No.51105024)
文摘There is less research on vertical sculptured grinding technology. Especially in high vertical surface grinding process with the cup abrasive wheel, the thermal damage is prone to happen and undermine the grinding surface integrity. This problem limits to improve the grinding efficiency and the grinding ratio greatly. Through the analysis of vertical surface grinding process and features in depth, this paper revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel. Based on the previous research achievements, the grinding experiments on TC4 (Ti-6A1-4V) and GH4169 are carried out utilizing the self-inhaling internal cooling wheel. The experimental results show that the self-inhaling internal cooling wheel can efficiently reduce the grinding surface temperature. Moreover, the inherent mechanism of reducing the grinding temperature using the internal cooling method is revealed. Meanwhile, under the same grinding conditions, the grinding ratio during the experiments on GH4169 using self-inhaling internal cooling method is about 3 times as high as using conventional external cooling method. And the grinding forces can be reduced by about 20%. This research revealed the inherent mechanism of higher grinding temperature in the process of vertical sculptured grinding using the cup wheel, which provides theoretical basis for the design and application of self-inhaling internal cooling wheel. At the same time, an efficient and non-invasive surface grinding method of TC4 and GH4169 is presented.
基金supported by the General Program (No.60774022)the State Key Program of National Natural Science Foundation of China(No.60834001)the State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University (No.RCS2009ZT011)
文摘In this paper, iterative learning control (ILC) design is studied for an iteration-varying tracking problem in which reference trajectories are generated by high-order internal models (HOLM). An HOlM formulated as a polynomial operator between consecutive iterations describes the changes of desired trajectories in the iteration domain and makes the iterative learning problem become iteration varying. The classical ILC for tracking iteration-invariant reference trajectories, on the other hand, is a special case of HOlM where the polynomial renders to a unity coefficient or a special first-order internal model. By inserting the HOlM into P-type ILC, the tracking performance along the iteration axis is investigated for a class of continuous-time nonlinear systems. Time-weighted norm method is utilized to guarantee validity of proposed algorithm in a sense of data-driven control.
文摘AIM:To assess the impact of macular surgery on the functional and anatomic outcomes of the patients in different grades of epiretinal membrane(ERM).METHODS:Seventy-one eyes of 71 patients who underwent 23-gauge transconjunctival sutureless pars plana vitrectomy for primary isolated ERM were evaluated in this study.RESULTS:There were 38 females(53.5%) and 33 males(46.5%).The average age of the patients was 68.1 y(range 42-89 y).Mean follow up period was 14 mo(range 6-26 mo).The cases were divided into two subgroups of cellophane maculopathy(CM) and macular pucker(MP).An improvement was observed in the postoperative best-corrected visual acuity(BCVA),as well as a decrement in central foveal thickness(CFT) in both groups(both of these being statistically significant;P=0.001).In comparison between two groups,it was found that there was a significant improvement on BCVA and CFT in CM group than MP group(P=0.01).Furthermore,the postoperative fundus findings regarding RPE alterations and macular edema were significantly higher in MP group when compared to the CM group(P=0.01).CONCLUSION:ERM and internal limiting membrane peeling surgery can lead to a significant reduction of CFT and visual improvements in idiopathic ERM.A long-term ERM persistence will cause unrecoverable retinal damage and visual loss.
文摘Internal bond (IB) strength is one of the most important me- chanical properties that indicate particleboard quality. The aim of this study was to find a simple regression model that considers the most important parameters that can influence on IB strength. In this study, IB strength was predicted by three kinds of equations (linear, quadratic, and exponential) that were based on the percentage of adhesive (8%, 9.5%, and 11%), particle size (+5, -5 +8, -8 12, and -12 mesh), and density (0.65, 0.7, and 0.75 g/cm3). Our analysis of the results (using SHAZAM 9 software) showed that the exponential function best fitted the experi- mental data and predicted the IB strength with 18~,/0 error. In order de- crease the error percentage, the Buckingham Pi theorem was used to build regression models for predicting IB strength based on particle size,
基金the Technology Research Program of Shaanxi Province, No. 2009K18-02
文摘The present study observed hemodynamic changes in 26 patients with cerebral arteriosclerosis using a cerebral circulation dynamics detector and transcranial Doppler. In patients with cerebral arteriosclerosis the blood supply and flow rate in the bilateral carotid arteries and the blood flow rate in the anterior cerebral and middle cerebral arteries were similar to normal controls, but the cerebral vascular resistance, critical pressure and pulsatility index were increased, and cerebral arterial elasticity and cerebral blood flow autoregulation were decreased. Compared with the lesioned hemisphere of patients with cerebral infarction, the total blood supply and blood flow rate of patients with cerebral arteriosclerosis were higher. Compared with normal subjects, patients with cerebral arteriosclerosis exhibited cognitive disturbances, mainly in short-term memory, attention, abstract capability, and spatial and executive dysfunction. Results showed that cerebral arteriosclerosis does not directly affect the blood supply of a cerebral hemisphere, but affects cognitive function. The increased cerebral vascular resistance and reduced autoregulation of cerebral blood vessels may be important hemodynamic mechanisms of arteriosclerosis-induced cerebral infarction.
基金National Natural Science Foundation of China(No.30600624)
文摘Objective: To construct recombinant adeno-associated virus co-expressing human vascular epithelial growth factor 165(hVEGF165) and bone morphogenetic protein 7(hBMPT), measure the virus titer and verify the recombination. Methods:The AAV helper-free system was used as basis to generate recombinant AAV. The IRES sequence of plasmid plRES was cut down and subcloned into ITR/ MCS containing vector pAAV-MCS to construct recombinant plasmid pAAV-MCSa-IRES-MCSb. The hVEGF165 and hBMP7 gene was amplified by PCR and inserted into upstream MCSa and downstream MCSb respectively. Then, recombinant plasmid pAAV- hVEGF165-IRES-hBMP7, pAAV-RC and pHelper were co-transfected into AAV-293 cells to complete rAAV-hVEGF165-IRES-hBMP7 packaging. The GFP labeled rAAV-IRES-GFP was simultaneously packaged by using the parallel plasmid pAAV-IRES-hrGFP. The efficiency of AAV packaging was monitored under fluorescent microscope and recombinant viral particles were harvested from infected AAV-293 cells. The virus titer was measured by infecting AAV-HT1080 cells, and the recombinant AAV-hVEGF165-IRES-hBMP7 was verified by PCR of the exogenous interest genes. Results:Recombinant pAAV-hVEGF165-IRES-hBMP7 was verified by double digestion. GFP expression in AAV-293 could be observed under fluorescent microscope 72 h after transfection and the system provided a high packing ratio of 95%. The recombinant adeno-associated virus has a high titer of 5.5 ×10^11vp/ml, and AAV-HT 1080 was infected at a ratio of 90%. The recombinant virus was confirmed by PCR of exogenous hBMP7 and hVEGF165 gene. Conclusion:Recombinant rAAV-hVEGF165-IRES-hBMP7 was successfully constructed with a high virus titer, which may offer foundation for in vitro and in vivo experiments of hVEGF165 and hBMP7 co-expression and provide a new method for gene therapy of bone regeneration.
文摘在英语世界中,对jus gentium的翻译最初以保留其拉丁语形态为主。经过三次语义转移,罗马法对jus gentium赋予了更多的自然理性色彩,jus naturale也成了jus gentium的同义词之一。阿奎那的“ius inter gentes”(民族间法)和“ius inter omnes gentes”(全民族间法)推动“jus gentium”现代国际法内涵逐渐饱满,后来格劳秀斯将其基本确定为现代的“国际法”。边沁创制的“international law”一词至今仍存在争议,与“law of nations”并行使用的同时,“universal public law”(公法)、“transnational law”(跨国法)、“universal law”(普遍法)等术语均未能弱化“international law”的稳固地位。在中国,“international law”通过晚清政府的“各国律例”被降格为国内法,但也在一定程度上承认了各国的主体地位。日本未经转译等复杂的中间环节,将国际法支点术语“international law”创译为更贴近原作的“国际法”,精准地表现出了“国家之间的法”(interstate law)的内涵。
基金The authors thank the National Natural Science Foundation of China for financial support through research No. 71703130.
文摘The astonishing surge in China's international trade is the result of comprehensive economic reforms in the 1980s and 1990s. Trade was further bolstered by China's accession to the World Trade Organization (WTO) in 2001. We examine several aspects of China's international trade that might help to explain its surprisingly fast growth and its ever-growing role in the global economy. A large number of studies have analyzed how trade liberalization, the WTO accession in particular, has profoundly changed the Chinese economy. We survey notable contributions to this literature that analyze the effects of trade liberalization on Chinese firms, individuals and households. Meanwhile, China "s exports have had various effects on importing countries and the enormous growth of China's exports is seen by some observers as posing a threat to China "s trading partners. Therefore, we discuss the emerging literature on the effects of China "s spectacular export growth on consumers, labor markets, innovation, media and politics in foreign countries. Given the new domestic and external circumstances, the Chinese Government is determined to push for the formation of a new trade structure characterized by broad opening up to transform China into a strong trading powerhouse.
文摘An examination of available data reveals large trade misinvoicing between China and its trade partners. The analysis finds a net trade misinvoicing of US$287.6bn between 2000 and 2005, while the full magnitude of unrecorded trade is estimated at US$1.4tn. China needs to establish more effective management of its international trade flows. At the same time, the international community needs to provide more effective governance mechanisms to address trade misinvoicing.
文摘Using an internationally linked patent database, this paper compares the types of R &D activities undertaken by multinationals in China by home country and industry. In China, multinationals recently began investing in R&D, mainly in the areas of product and manufacturing process development. However, US firms, which are the most actively invested in R&D, are involved in some technology-driven R&D activities; European firms are inclined toward market-driven R &D, while Japanese firms, which lag behind the other two, focus on production-driven R &D. This pattern may be related to the relative competitiveness of each country: Japanese firms are strong in electronics and automobiles, where production process improvement is important, while US firms flourish in science-based industries, such as pharmaceuticals and software, where interacting with the local science base is a critical factor.
文摘The Lin-gang Special Area of the China(Shanghai)Pilot Free Trade Zone(FTZ)was off icially unveiled on August 20 after an overall plan was issued by the State Council on August 6.The special area is one of the measures for advancing further opening up initiated by Chinese President Xi Jin ping at the First China International Import Expo in November 2018.
基金Supported by the National Science Fund of China for Distinguished YoungScholars(30325047).
文摘Interactions between an isolate of dark septate endophytes (DSE) and roots of Dendrobium nobile Lindl. seedlings are reported in this paper. The isolate was obtained from orchid mycorrhizas on Dendrobium sp. in subtropical forest. The fungus formed typical orchid mycorrhiza in aseptic co-culture with D. nobile seedlings on modified Murashige-Skoog (MMS) medium. Anatomic observations of the infected roots showed that the DSE hyphae invaded the velamen layer, passed through passage cells in exodermis, entered the cortex cells, and then formed fungal pelotons of orchid mycorrhiza. D. nobile seedlings' plant height, stem diameter, new roots number and biomass were greatly enhanced by inoculating the fungus to seedlings. The fungus was identified as Leptodontidium by sequencing the polymerase chain reaction-amplified rDNA ITS1-5,8S-ITS2 (internal transcribed spacer (ITS)) regions and comparison with similar taxa.
基金the National Natural Science Foundation of China (Grant Nos. 61072145, 41176016)the Fundfor Creative Research Groups by National Natural Science Foundation of China (Grant No. 41121064)the State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences (Grant No. LTO1104)
文摘In this study, an analysis on the internal wave generation via the gravity collapse mechanism is carried out based on the theoretical formulation and the numerical simulation. With the linear theoretical model, a rectangle shape wave is generated and propagates back and forth in the domain, while a two-dimensional non-hydrostatic numerical model could reproduce all the observed phenomena in the laboratory experiments conducted by Chen et al. (2007), and the related process realistically. The model results further provide more quantitative information in the whole domain, thus allowing an in depth understanding of the corresponding internal solitary wave generation and propagation. It is shown that the initial type of the internal wave is determined by the relative height between the perturbation and the environmental density interface, while the final wave type is related to the relative height of the upper and lower layers of the environmental fluid. The shape of the internal wave generated is consistent with that predicted by the KdV and EKdV theories if its amplitude is small, as the amplitude becomes larger, the performance of the EKdV becomes better after the wave adjusts itself to the ambient stratification and reaches an equilibrium state between the nonlinear and dispersion effects. The evolution of the mechanical energy is also analyzed.
基金This paper is supported by the project of National Natural Science Foundation of China (No. 51405469, No. 51275505), and science and technology support plan key projects of Jiangsu province (No. BE2013003).
文摘Compared to single arm robot system, dual arm robot has the ability of performing human-like dexterity and cooperation. Dual arm cooperative operation has attracted more and more attention in industrial applications, such as in assembly of complex parts, manufacturing tasks and handling objects. A unified dynamic control method, which is divided into three modes, namely, independent mode, dependent mode, and half dependent mode, is proposed for a redundant dual arm robot with focus on the movement and force of the desired task being operated. Attention is devoted to develop a unified formulation of the above three modes. In addition, a closed form of inverse kinematic solution instead of numerical integration approach is proposed with the aim to guarantee position accuracy. Different from traditional dynamic controllers, where the independent redundancy resolution is obtained based on particular velocity or acceleration levels, here the two dynamic controllers are improved by combining a closed form of inverse kinematic solution with velocity and acceleration levels. Furthermore, the theoretical results of the proposed control method are validated by simulations and experiments.