In the last two decades, China has become one of the areas that have the greatest potential in industrial production, thus it has ranked second only to USA in the flow of international capital. By the end of 1998, the...In the last two decades, China has become one of the areas that have the greatest potential in industrial production, thus it has ranked second only to USA in the flow of international capital. By the end of 1998, the real value of FDI (Foreign Direct Investment) in China has utilized has added up to $268.1 billion. The big flow of FDI has not only promoted the development of social economy, but also worsened the existing regional difference by choosing spatial location. Under this circumstance, China’s economy faces new restrictions and opportunities while adjusting its regional structure and industrial structure. So it is more and more important for us how to seize the opportunity, to seek the regularity of FDI in choosing location from the aspect of space, to set up relevant strategy to direct FDI at inland regions (areas deficient of capital), and to make appropriate policies, esp. the industrial and regional policies so as for FDI to exert positive influence and avoid negative influence on China and its regional economy and society. Based on the latest domestic and overseas materials and data of the FDI in China, combining with the investigation of the enterprises, this paper has systematically revealed the progress of development of the FDI in China and the developing conditions of the main enterprises directly invested by foreign capital since the reform and opening-up in China. The characters of FDI such as spatial concentration, transference as time goes on, change of the technical content and up-gradation of industrial structure and their forming mechanism have been studied. Then the basic conclusions have been made as follows. Firstly, FDI has been highly concentrated in space. But as time goes by, it has been transferring from coastal regions to inland ones, from big cities to their surrounding districts, and the degree of concentration is decreasing. Secondly, the technical content of the invested projects has gradually increased and the up-gradation of the industrial structure is obvious. Thirdly, the regional choice of the FDI in China is mainly affected by labor and other productive factors. The relative change of the cost of productive factors in different regions since the reform and opening-up is one of the main factors that have caused the spatial transference of the FDI in China. Fourthly, as people’s income increases and the accumulation of the capacity of the technique and labor advances, FDI whose aim is to get more market has increased and tended to transfer from coastal regions to inland ones. Fifthly, the changes of the industrial structure of the main areas and countries who have directly invested in China and the changes of inter-regional industries and regional policies in China are also the important factors that affect the industries directly invested by foreign capital and their spatial transference.展开更多
Background:Many disease-specific factors such as muscular weakness,increased muscle stiffness,varying postural strategies,and changes in postural reflexes have been shown to lead to postural instability and fall risk ...Background:Many disease-specific factors such as muscular weakness,increased muscle stiffness,varying postural strategies,and changes in postural reflexes have been shown to lead to postural instability and fall risk in people with Parkinson's disease(PD).Recently,analytical techniques,inspired by the dynamical systems perspective on movement control and coordination,have been used to examine the mechanisms underlying the dynamics of postural declines and the emergence of postural instabilities in people with PD.Methods:A wavelet-based technique was used to identify limit cycle oscillations(LCOs) in the anterior–posterior(AP) postural sway of people with mild PD(n = 10) compared to age-matched controls(n = 10).Participants stood on a foam and on a rigid surface while completing a dual task(speaking).Results:There was no significant difference in the root mean square of center of pressure between groups.Three out of 10 participants with PD demonstrated LCOs on the foam surface,while none in the control group demonstrated LCOs.An inverted pendulum model of bipedal stance was used to demonstrate that LCOs occur due to disease-specific changes associated with PD:time-delay and neuromuscular feedback gain.Conclusion:Overall,the LCO analysis and mathematical model appear to capture the subtle postural instabilities associated with mild PD.In addition,these findings provide insights into the mechanisms that lead to the emergence of unstable posture in patients with PD.展开更多
For improving the performance of differential geometric guidance command(DGGC), a new formation of this guidance law is proposed, which can guarantee the finite time convergence(FTC) of the line of sight(LOS) rate to ...For improving the performance of differential geometric guidance command(DGGC), a new formation of this guidance law is proposed, which can guarantee the finite time convergence(FTC) of the line of sight(LOS) rate to zero or its neighborhood against maneuvering targets in three-dimensional(3D) space. The extended state observer(ESO) is employed to estimate the target acceleration, which makes the new DGGC more applicable to practical interception scenarios. Finally, the effectiveness of this newly proposed guidance command is demonstrated by the numerical simulation results.展开更多
The purpose of this study was to investigate the effect of Laggera alata flavonen (LAF) on the inhibit- ing effect of human ovarian cancer HO-8910 cells proliferation and its possible mechanism in vitro. Methods: H...The purpose of this study was to investigate the effect of Laggera alata flavonen (LAF) on the inhibit- ing effect of human ovarian cancer HO-8910 cells proliferation and its possible mechanism in vitro. Methods: Human ovarian cancer HO-8910 cells were cultured in vitro. Inhibitory effect of LAF on the viability of HO-8910 cells was evaluated by the MTT assay. Apoptotic effect of different concentrations of LAF on HO-8910 cells was assessed by AO/EB staining and FCM with propidium iodide (PI) staining. Expression of proteins related to apoptosis was analyzed by Western blot. Results: LAF significantly inhibited the viability of HO-8910 cells proliferation in a dose-dependent and time-dependent manner, there were statistical significance compared with NS group (P 〈 0.05), and the ICso was 4.28 pg/mL for 48 h. The cells treated with LAF showed typical morphological change and apoptotic rate increased by FCM in a dose-dependent, and there was notable dif- ference compared with NS group (P 〈 0.05). Western blot showed that expression of Fas, caspase-8, tBid and Cyto-c proteins were up-regulated after treatment with LAF for 48 h in a concentration dependent. Conclusion: LAF could inhibit HO-8910 cells proliferation and induce apoptosis, which may be through the pathway of death receptor in vitro.展开更多
When orthopedic joints coated by hydroxyapatite(HA) were implanted in the human body, they release wear debris into the surrounding tissues. The generation and accumulation of wear particles will induce aseptic loosen...When orthopedic joints coated by hydroxyapatite(HA) were implanted in the human body, they release wear debris into the surrounding tissues. The generation and accumulation of wear particles will induce aseptic loosening. However, the potential bioeffect and mechanism of HA-coated orthopedic implants on bone cells are poorly understood. In this study, defect-related luminescent bur-like hydroxyapatite(BHA) microspheres with the average diameter of 7–9 μm which are comparable to that of the wear-debris particles from aseptically loosened HA implants or HA debris have been synthesized by hydrothermal synthesis and the MC3 T3-E1 cells were set as a cells model to study the potential bioeffect and mechanism of BHA microspheres. The studies demonstrated that BHA microspheres could be taken into MC3 T3-E1 cells via endocytosis involved in micropinocytosisand clathrin-mediated endocytosis process, and exert cytotoxicity effect. BHA microspheres could induce the cell apoptosis by intracellular production of reactive oxygen species(ROS), which led to not only an increase in the permeability of lysosome and release of cathepsins B, but also mitochondrial dysfunction and DNA damage. Our results provide novel evidence to elucidate their toxicity mechanisms and might be helpful for more reasonable applications of HA-based orthopaedic implants in the future.展开更多
Objective:To study gene expression of collagen types IX and X in human lumbar intervertebral discs during aging and degeneratio n and to explore the role of collagen types IX and X in disc degeneration. Methods:Fetal,...Objective:To study gene expression of collagen types IX and X in human lumbar intervertebral discs during aging and degeneratio n and to explore the role of collagen types IX and X in disc degeneration. Methods:Fetal, adult and pathologic specimens were subjected t o in situ hybridization with cDNA probes to investigate mRNA-expressions of typ es IX and X collagen gene. Results:In fetal intervertebral discs, positive mRNA hybridiza tion signals of type IX collagen were concentrated in the nucleus pulposus and t he inner layer of anulus fibrosus. Interstitial matrix of the nucleus pulposus a lso showed positive type X collagen staining. Positive mRNA hybridization signal s of types IX and X were not detected in the middle and outer layers of anulus f ibrosus. In adult specimens, expression of type IX collagen mRNA was markedly de creased. No hybridization signals of type X collagen was observed. As for pathol ogical specimens, there was no gene expression of type IX collagen. In severe de generated discs from adults, there were focal positive expressions of type X col lagen. Conclusions:Obvious changes of collagen gene expression occur with aging. Expression of type IX collagen decreases in adult and pathological d iscs. Results of type X collagen expression suggest that type X collagen is expr essed only in older adult and senile discs (i.e., when disc degeneration has alr eady reached a terminal stage), indicating the terminal stage of degeneration.展开更多
In this paper, we study the existence, uniqueness and stability of memristor-based syn- chronous switching neural networks with time delays. Several criteria of exponential stability are given by introducing multiple ...In this paper, we study the existence, uniqueness and stability of memristor-based syn- chronous switching neural networks with time delays. Several criteria of exponential stability are given by introducing multiple Lyapunov functions. In comparison with the existing publications on simplice memristive neural networks or switching neural net- works, we consider a system with a series of switchings, these switchings are assumed to be synchronous with memristive switching mechanism. Moreover, the proposed stability conditions are straightforward and convenient and can reflect the impact of time delay on the stability. Two examples are also presented to illustrate the effectiveness of the theoretical results.展开更多
基金the important project of National Natural Science Foundation of China (49831003)and the important project of the Ninth Five-Year
文摘In the last two decades, China has become one of the areas that have the greatest potential in industrial production, thus it has ranked second only to USA in the flow of international capital. By the end of 1998, the real value of FDI (Foreign Direct Investment) in China has utilized has added up to $268.1 billion. The big flow of FDI has not only promoted the development of social economy, but also worsened the existing regional difference by choosing spatial location. Under this circumstance, China’s economy faces new restrictions and opportunities while adjusting its regional structure and industrial structure. So it is more and more important for us how to seize the opportunity, to seek the regularity of FDI in choosing location from the aspect of space, to set up relevant strategy to direct FDI at inland regions (areas deficient of capital), and to make appropriate policies, esp. the industrial and regional policies so as for FDI to exert positive influence and avoid negative influence on China and its regional economy and society. Based on the latest domestic and overseas materials and data of the FDI in China, combining with the investigation of the enterprises, this paper has systematically revealed the progress of development of the FDI in China and the developing conditions of the main enterprises directly invested by foreign capital since the reform and opening-up in China. The characters of FDI such as spatial concentration, transference as time goes on, change of the technical content and up-gradation of industrial structure and their forming mechanism have been studied. Then the basic conclusions have been made as follows. Firstly, FDI has been highly concentrated in space. But as time goes by, it has been transferring from coastal regions to inland ones, from big cities to their surrounding districts, and the degree of concentration is decreasing. Secondly, the technical content of the invested projects has gradually increased and the up-gradation of the industrial structure is obvious. Thirdly, the regional choice of the FDI in China is mainly affected by labor and other productive factors. The relative change of the cost of productive factors in different regions since the reform and opening-up is one of the main factors that have caused the spatial transference of the FDI in China. Fourthly, as people’s income increases and the accumulation of the capacity of the technique and labor advances, FDI whose aim is to get more market has increased and tended to transfer from coastal regions to inland ones. Fifthly, the changes of the industrial structure of the main areas and countries who have directly invested in China and the changes of inter-regional industries and regional policies in China are also the important factors that affect the industries directly invested by foreign capital and their spatial transference.
基金the National Science Foundation for partial financial support for this project provided through the grant CMMI-1300632Purdue University for partial financial support for this project through a Research Incentive Grant
文摘Background:Many disease-specific factors such as muscular weakness,increased muscle stiffness,varying postural strategies,and changes in postural reflexes have been shown to lead to postural instability and fall risk in people with Parkinson's disease(PD).Recently,analytical techniques,inspired by the dynamical systems perspective on movement control and coordination,have been used to examine the mechanisms underlying the dynamics of postural declines and the emergence of postural instabilities in people with PD.Methods:A wavelet-based technique was used to identify limit cycle oscillations(LCOs) in the anterior–posterior(AP) postural sway of people with mild PD(n = 10) compared to age-matched controls(n = 10).Participants stood on a foam and on a rigid surface while completing a dual task(speaking).Results:There was no significant difference in the root mean square of center of pressure between groups.Three out of 10 participants with PD demonstrated LCOs on the foam surface,while none in the control group demonstrated LCOs.An inverted pendulum model of bipedal stance was used to demonstrate that LCOs occur due to disease-specific changes associated with PD:time-delay and neuromuscular feedback gain.Conclusion:Overall,the LCO analysis and mathematical model appear to capture the subtle postural instabilities associated with mild PD.In addition,these findings provide insights into the mechanisms that lead to the emergence of unstable posture in patients with PD.
文摘For improving the performance of differential geometric guidance command(DGGC), a new formation of this guidance law is proposed, which can guarantee the finite time convergence(FTC) of the line of sight(LOS) rate to zero or its neighborhood against maneuvering targets in three-dimensional(3D) space. The extended state observer(ESO) is employed to estimate the target acceleration, which makes the new DGGC more applicable to practical interception scenarios. Finally, the effectiveness of this newly proposed guidance command is demonstrated by the numerical simulation results.
文摘The purpose of this study was to investigate the effect of Laggera alata flavonen (LAF) on the inhibit- ing effect of human ovarian cancer HO-8910 cells proliferation and its possible mechanism in vitro. Methods: Human ovarian cancer HO-8910 cells were cultured in vitro. Inhibitory effect of LAF on the viability of HO-8910 cells was evaluated by the MTT assay. Apoptotic effect of different concentrations of LAF on HO-8910 cells was assessed by AO/EB staining and FCM with propidium iodide (PI) staining. Expression of proteins related to apoptosis was analyzed by Western blot. Results: LAF significantly inhibited the viability of HO-8910 cells proliferation in a dose-dependent and time-dependent manner, there were statistical significance compared with NS group (P 〈 0.05), and the ICso was 4.28 pg/mL for 48 h. The cells treated with LAF showed typical morphological change and apoptotic rate increased by FCM in a dose-dependent, and there was notable dif- ference compared with NS group (P 〈 0.05). Western blot showed that expression of Fas, caspase-8, tBid and Cyto-c proteins were up-regulated after treatment with LAF for 48 h in a concentration dependent. Conclusion: LAF could inhibit HO-8910 cells proliferation and induce apoptosis, which may be through the pathway of death receptor in vitro.
基金supported by the National Natural Science Foundation of China (21301046, 51302062)the Natural Science Foundation of Hebei Province (B2017201125, B2017201100)+1 种基金the Second Batch of Top Youth Talent Support Program of Hebei ProvinceDistinguished Young Scholars Fund of Hebei University (2015JQ04)
文摘When orthopedic joints coated by hydroxyapatite(HA) were implanted in the human body, they release wear debris into the surrounding tissues. The generation and accumulation of wear particles will induce aseptic loosening. However, the potential bioeffect and mechanism of HA-coated orthopedic implants on bone cells are poorly understood. In this study, defect-related luminescent bur-like hydroxyapatite(BHA) microspheres with the average diameter of 7–9 μm which are comparable to that of the wear-debris particles from aseptically loosened HA implants or HA debris have been synthesized by hydrothermal synthesis and the MC3 T3-E1 cells were set as a cells model to study the potential bioeffect and mechanism of BHA microspheres. The studies demonstrated that BHA microspheres could be taken into MC3 T3-E1 cells via endocytosis involved in micropinocytosisand clathrin-mediated endocytosis process, and exert cytotoxicity effect. BHA microspheres could induce the cell apoptosis by intracellular production of reactive oxygen species(ROS), which led to not only an increase in the permeability of lysosome and release of cathepsins B, but also mitochondrial dysfunction and DNA damage. Our results provide novel evidence to elucidate their toxicity mechanisms and might be helpful for more reasonable applications of HA-based orthopaedic implants in the future.
文摘Objective:To study gene expression of collagen types IX and X in human lumbar intervertebral discs during aging and degeneratio n and to explore the role of collagen types IX and X in disc degeneration. Methods:Fetal, adult and pathologic specimens were subjected t o in situ hybridization with cDNA probes to investigate mRNA-expressions of typ es IX and X collagen gene. Results:In fetal intervertebral discs, positive mRNA hybridiza tion signals of type IX collagen were concentrated in the nucleus pulposus and t he inner layer of anulus fibrosus. Interstitial matrix of the nucleus pulposus a lso showed positive type X collagen staining. Positive mRNA hybridization signal s of types IX and X were not detected in the middle and outer layers of anulus f ibrosus. In adult specimens, expression of type IX collagen mRNA was markedly de creased. No hybridization signals of type X collagen was observed. As for pathol ogical specimens, there was no gene expression of type IX collagen. In severe de generated discs from adults, there were focal positive expressions of type X col lagen. Conclusions:Obvious changes of collagen gene expression occur with aging. Expression of type IX collagen decreases in adult and pathological d iscs. Results of type X collagen expression suggest that type X collagen is expr essed only in older adult and senile discs (i.e., when disc degeneration has alr eady reached a terminal stage), indicating the terminal stage of degeneration.
文摘In this paper, we study the existence, uniqueness and stability of memristor-based syn- chronous switching neural networks with time delays. Several criteria of exponential stability are given by introducing multiple Lyapunov functions. In comparison with the existing publications on simplice memristive neural networks or switching neural net- works, we consider a system with a series of switchings, these switchings are assumed to be synchronous with memristive switching mechanism. Moreover, the proposed stability conditions are straightforward and convenient and can reflect the impact of time delay on the stability. Two examples are also presented to illustrate the effectiveness of the theoretical results.