The epidermis, and in particular its outermost layer, the stratum corneum, contributes much of the barrier function of the skin and is a readily visible representation of skin health. Maintaining the health of the ski...The epidermis, and in particular its outermost layer, the stratum corneum, contributes much of the barrier function of the skin and is a readily visible representation of skin health. Maintaining the health of the skin barrier has arguably become more important than ever in the modern world, in which a large majority of people are exposed to environmental insults. These external factors can damage the integrity of the skin barrier and prematurely age the skin. Therefore, it has become increasingly important to maintain and protect the stratum corneum. Here, we briefly review the complex, multilayered structure of the skin and relate it to clinically translatable function, with an emphasis on the stratum corneum. In the context of epidermal structure and function, the formulation and clinical data for Phelityl® Reviving Cream will be reviewed. Phelityl Reviving Cream was shown to be associated with improvements in both immediate- and long-term parameters, including a significant positive effect on the skin barrier and immediate and long-lasting hydration.展开更多
目的:分析血浆高同型半胱氨酸(Hcy)对Revive支架取栓治疗急性前循环大血管闭塞性脑卒中预后的影响。方法:选取2022年1月—2023年5月博罗县人民医院收治的应用Revive支架取栓治疗的41例急性前循环大血管闭塞性脑卒中患者。根据血清Hcy水...目的:分析血浆高同型半胱氨酸(Hcy)对Revive支架取栓治疗急性前循环大血管闭塞性脑卒中预后的影响。方法:选取2022年1月—2023年5月博罗县人民医院收治的应用Revive支架取栓治疗的41例急性前循环大血管闭塞性脑卒中患者。根据血清Hcy水平(血清Hcy≥15μmol/L定义为高Hcy)分为高Hcy组(n=20)和正常Hcy组(n=21)(血清Hcy<15μmol/L定义为正常)。比较两组患者行Revive支架取栓术后血管再通率、术后24 h NIHSS评分、出院时NIHSS评分、症状性颅内出血及治疗结局。结果:高Hcy组在术前、术后24 h及出院当天的Hcy水平、NIHSS评分均显著高于正常Hcy组(P<0.05);高Hcy组的血管再通(mTICI评级1-2a)的患者占比及颅内出血症状(sICH)发生率均高于正常Hcy组,差异有统计学意义(P<0.05),高Hcy组的90 d内预后良好(MRS≤2分)患者占比低于正常Hcy组,差异有统计学意义(P<0.05)。结论:Hcy不利于Revive支架取栓治疗急性前循环大血管闭塞性脑卒中患者术后神经功能的恢复和闭塞血管再通,术前维持Hcy正常有利于提升患者术后预后效果。展开更多
In the international communist movement in the 19th century,the national uprising in Europe and the workers’movement were intertwined,forming a complex historical background.The Polish National Uprising in 1863 becam...In the international communist movement in the 19th century,the national uprising in Europe and the workers’movement were intertwined,forming a complex historical background.The Polish National Uprising in 1863 became a historical opportunity for the establishment of the First International.Although the unity of the British workers and the French workers was the realistic basis of the First International,the French workers showed a vague attitude different from the British workers on the Polish issue.In the first Congress of the First International,the French workers who almost are Proudhonists rejected the issue of supporting the Polish nation against the Tsar Russian oppression.Pierre-Joseph Proudhon did not link the Polish issue with the workers’movement,while he insisted that social and economic issues should not be confused with political reconstruction,and artificially separated national revival from workers’liberation.In order to promote and assist the establishment of the First International,Marx made certain consideration and concessions on national issues in the formulation of its declaration and constitution.Then Engels,commissioned by Marx,made some specific interpretations that they based on the difference between nation and nationality,and adhere it to the international national principle,both clearly shows the Marxism view of nation state,reveals the risk if international communist movement limited to the principle of nationalities,and also further reveals the importance to combine two great cause,national revival and workers liberation.展开更多
The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationshi...The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationship between street centrality and land use patterns or commercial activities at interurban or intraurban scales. We considered Shichahai in this study to determine if street centrality applied at the street scale and if the street network was the only factor influencing the selection of store location. First, the nearest neighbor index, nearest neighbor hierarchical spatial cluster(NNHSC), and kernel density estimation(KDE) methods were used to provide baseline spatial distributions of commercial stores. Second, urban network analysis(UNA) tools were used to measure the street centrality indices under two conditions, with and without the weighting of cultural relics calculated by a principal component analysis(PCA). Finally, both store locations and centrality values at nodes were transformed to one unit(raster pixel) for a correlation analysis.The results showed that three of the four store types were clustered and had their own hotspots that were mostly located in the eastern and central parts of city blocks. The most momentous findings were determined from the street centrality indices. Among the three store types with correlation coefficients above 0.5, all centrality indices with landmark weighting, except straightness, had higher correlations,with closeness with landmark weighting having the highest correlation, followed by betweenness with landmark weighting. Therefore,we statistically concluded that street centrality could apply at the street scale and that the street network was not the only factor that influenced store location pattern, with landmarks also playing a significant role. The results provide guidance in determining the selection strategy for stores in a historic conservation area.展开更多
Rural areas in the K?odzko Region were subject to a long-term depopulation,marginalization,and long-lasting socio-economic decline since the 19th century.In recent years,however,the study area has been subject to a sh...Rural areas in the K?odzko Region were subject to a long-term depopulation,marginalization,and long-lasting socio-economic decline since the 19th century.In recent years,however,the study area has been subject to a shift in socio-economic trends that show rural revival.The main goal of the research is to assess the actual role of tourism in socio-economic revival of rural areas in the K?odzko Region.To determine the dynamics of the tourism function development,statistical data were used and an inventory of tourism beds in accommodation facilities was conducted.The results show that there was a substantial development of the tourism function in the study area and its most intense scale was noted in the depopulating villages,as evidenced by the increase in the numbers of tourism facilities and numbers of tourism beds.Therefore,it can be concluded that the development of tourism contributed to the limitation of negative socioeconomic processes in the area and,in the case of some villages,even to the reversal of these trends,which might testify to the rural revival.Moreover,the improvement of the socio-economic situation is visible also in the villages that do not have significant tourist values but are in the neighbourhood of tourism hotspots.This observation might be important for forecasting future development and planning of rural areas.展开更多
We introduce the concept of truncated states obtained via iterative processes (TSI) and study its statistical features, making an analogy with dynamical systems theory (DST). As a specific example, we have studied...We introduce the concept of truncated states obtained via iterative processes (TSI) and study its statistical features, making an analogy with dynamical systems theory (DST). As a specific example, we have studied TSI for the doubling and the logistic functions, which are standard functions in studying chaos. TSI for both the doubling and logistic functions exhibit certain similar patterns when their statistical features are compared from the point of view of DST.展开更多
Taking the intensity-dependent coupling between atoms and cavity mode into account, we investigate a system consisting of N homogeneously broadened two-level atoms interacting with the field inside a single-mode Fabry...Taking the intensity-dependent coupling between atoms and cavity mode into account, we investigate a system consisting of N homogeneously broadened two-level atoms interacting with the field inside a single-mode Fabry- Perot cavity containing a nonlinear Kerr-like medium. We derive the steady-state bistable behaviour of the system, and further analyse in details the influence of several critical parameters on the bistable behaviour.展开更多
We report the long time dynamical behaviour of ac Stark effect in a simple quantum model in which two level atoms interact with quantized coherent radiation field. A new phenomenon of periodic quantum collapse and rev...We report the long time dynamical behaviour of ac Stark effect in a simple quantum model in which two level atoms interact with quantized coherent radiation field. A new phenomenon of periodic quantum collapse and revival of the ac Stark shift of energy level due to ac Stark effect is expressed accurately by analysing the phase of transition probability amplitude. The analytic prediction is confirmed by the numerical results.展开更多
The nonequilibrium phase transition and the symmetry revival induced by time delay in a bistable system are investigated. The stationary probability distribution function (SPDF) of the bistable system with time dela...The nonequilibrium phase transition and the symmetry revival induced by time delay in a bistable system are investigated. The stationary probability distribution function (SPDF) of the bistable system with time delay and correlated noises are calculated by an analytical method and stochastic simulation respectively. The analytical and simulative results indicate that: (1) There is a certain value of λ(λ denotes the strength of correlations between the multiplicative and additive noises) to make the SPDF symmetric under some time delay; however, above or below the given value, the symmetry will be broken; (2) With the monotonic change of λ, the unimodal peak structure of SPDF becomes bimodal at the beginning, then it becomes unimodal again; this means that there is a reentrance phenomenon in the process; (3) There is a critical value of delay time, which makes the lower peak of SPDF equal to the higher one under the critical condition. This means that the symmetry revival phenomenon emerges.展开更多
AD = 1 position-dependent mass approach to constructing nonlinear quantum states for a modified Coulomb potential is used to generate Gazeau–Klauder coherent states. It appears that their energy eigenvalues are scale...AD = 1 position-dependent mass approach to constructing nonlinear quantum states for a modified Coulomb potential is used to generate Gazeau–Klauder coherent states. It appears that their energy eigenvalues are scaled down by the quantum number and the nonlinearity coefficient. We study the basic properties of these states, which are found to be undefined on the whole complex plane, and some details of their revival structure are discussed.展开更多
We investigate interference properties of a trapped atom interferometer where two symmetric optical dipole traps(ODTs)act as the atomic wave-packets splitter and combiner with internal state labelling.After the prepar...We investigate interference properties of a trapped atom interferometer where two symmetric optical dipole traps(ODTs)act as the atomic wave-packets splitter and combiner with internal state labelling.After the preparation of initial superposition states,the atomic wave-packet is adiabatically split and moves into two spatially separate asymmetric ODTs.The atomic wave-packets in two ODTs are then adiabatically recombined after a duration of free evolving in traps,completing the interference cycle of this atom interferometer.We show that the interferogram exhibits a series of periodic revivals in interference visibility.Furthermore,the revival period decreases as the asymmetry of two dipole potentials increases.By introducing an echo sequence to the interferometer,we show that while the echo effect is not influenced by the asymmetry of the two ODTs,the onset of periodic revivals changes by the echo sequence.Our study provides an effective method to cancel or compensate the phase shift caused by position and time correlated force.展开更多
The Hamiltonian of a superconducting charge qubit with a configuration of dc SQUID contains an interac-tion between the LC oscillator part and charge qubit.This interaction may leads to quantum state collapse and revi...The Hamiltonian of a superconducting charge qubit with a configuration of dc SQUID contains an interac-tion between the LC oscillator part and charge qubit.This interaction may leads to quantum state collapse and revivalwhich degrades the charge qubits and leads to serious decoherence.An analysis shows that the existing charge qubitparameters do not lead to this phenomenon,which is very good for the superconducting charge展开更多
An evaluation system of hydrocarbon-bearing availability of fault traps was established based on the comprehensive analysis of fault segment growth history,fine reservoir anatomy and geochemistry tracing,with the Qiko...An evaluation system of hydrocarbon-bearing availability of fault traps was established based on the comprehensive analysis of fault segment growth history,fine reservoir anatomy and geochemistry tracing,with the Qikou sag in the Bohai Bay Basin as target area.The displacement/separation transform and displacement gradient method were used to prove the interpretation reliability of fault traps.The method of maximum throw subtraction was used to recover the history of fault growth and determine the availability of the forming period of fault traps.Based on the quantitative relationship between shale gouge ratio and cross-fault pressure difference of known reservoirs in southern Qikou sag,the critical shale gouge ratio of fault lateral sealing was calculated at 20%,and the quantitative evaluation chart based on the relationship of"fault throw–sand-formation ratio and hydrocarbon column height"was constructed.Based on the results of reservoir fine anatomy and quantitative fluorescence tracing test shale smear factor method is suitable for evaluating the vertical sealing of faults in the caprock of the middle submember of first member of Paleogene Shahejie Formation,and the shale smear factor critical value is 3.5.The juxtaposition thickness method is suitable for evaluating vertical sealing of faults in the caprock of the second member of Paleogene Dongying Formation,and the critical juxtaposition thickness of fault is 70–80 m.By combining four factors,the availability of fault trap interpretation,the availability of the forming period of fault trap,the availability of fault lateral sealing and the availability of fault vertical sealing,the comprehensive evaluation chart on hydrocarbon-bearing availability of fault traps in Qikou sag has been established,which provides a reasonable basis for risk assessment of fault traps.展开更多
On March 6,2009,Russian Foreign Minister Sergei Lavrov and U.S.Secretary of State Hillary Clinton pressed together the"reset button"in Geneva,signifying that both sides wanted to thaw their bilateral ties si...On March 6,2009,Russian Foreign Minister Sergei Lavrov and U.S.Secretary of State Hillary Clinton pressed together the"reset button"in Geneva,signifying that both sides wanted to thaw their bilateral ties since it hit an all-time low over the Russia-Georgia conflict in August,2008.Although there were some positive signs in improving US-Russian ties,bilateral relations are hard to revive in the near future.展开更多
文摘The epidermis, and in particular its outermost layer, the stratum corneum, contributes much of the barrier function of the skin and is a readily visible representation of skin health. Maintaining the health of the skin barrier has arguably become more important than ever in the modern world, in which a large majority of people are exposed to environmental insults. These external factors can damage the integrity of the skin barrier and prematurely age the skin. Therefore, it has become increasingly important to maintain and protect the stratum corneum. Here, we briefly review the complex, multilayered structure of the skin and relate it to clinically translatable function, with an emphasis on the stratum corneum. In the context of epidermal structure and function, the formulation and clinical data for Phelityl® Reviving Cream will be reviewed. Phelityl Reviving Cream was shown to be associated with improvements in both immediate- and long-term parameters, including a significant positive effect on the skin barrier and immediate and long-lasting hydration.
文摘目的:分析血浆高同型半胱氨酸(Hcy)对Revive支架取栓治疗急性前循环大血管闭塞性脑卒中预后的影响。方法:选取2022年1月—2023年5月博罗县人民医院收治的应用Revive支架取栓治疗的41例急性前循环大血管闭塞性脑卒中患者。根据血清Hcy水平(血清Hcy≥15μmol/L定义为高Hcy)分为高Hcy组(n=20)和正常Hcy组(n=21)(血清Hcy<15μmol/L定义为正常)。比较两组患者行Revive支架取栓术后血管再通率、术后24 h NIHSS评分、出院时NIHSS评分、症状性颅内出血及治疗结局。结果:高Hcy组在术前、术后24 h及出院当天的Hcy水平、NIHSS评分均显著高于正常Hcy组(P<0.05);高Hcy组的血管再通(mTICI评级1-2a)的患者占比及颅内出血症状(sICH)发生率均高于正常Hcy组,差异有统计学意义(P<0.05),高Hcy组的90 d内预后良好(MRS≤2分)患者占比低于正常Hcy组,差异有统计学意义(P<0.05)。结论:Hcy不利于Revive支架取栓治疗急性前循环大血管闭塞性脑卒中患者术后神经功能的恢复和闭塞血管再通,术前维持Hcy正常有利于提升患者术后预后效果。
文摘In the international communist movement in the 19th century,the national uprising in Europe and the workers’movement were intertwined,forming a complex historical background.The Polish National Uprising in 1863 became a historical opportunity for the establishment of the First International.Although the unity of the British workers and the French workers was the realistic basis of the First International,the French workers showed a vague attitude different from the British workers on the Polish issue.In the first Congress of the First International,the French workers who almost are Proudhonists rejected the issue of supporting the Polish nation against the Tsar Russian oppression.Pierre-Joseph Proudhon did not link the Polish issue with the workers’movement,while he insisted that social and economic issues should not be confused with political reconstruction,and artificially separated national revival from workers’liberation.In order to promote and assist the establishment of the First International,Marx made certain consideration and concessions on national issues in the formulation of its declaration and constitution.Then Engels,commissioned by Marx,made some specific interpretations that they based on the difference between nation and nationality,and adhere it to the international national principle,both clearly shows the Marxism view of nation state,reveals the risk if international communist movement limited to the principle of nationalities,and also further reveals the importance to combine two great cause,national revival and workers liberation.
基金Under the auspices of National Natural Science Foundation of China(No.51478007,51178016)Project of Fundamental Research of Chinese Cultural Heritage Research Institute(No.2016-JBKY-08)
文摘The location pattern of different commercial stores in Shichahai, a historic conservation area in Beijing, was investigated from a street centrality perspective. Many previous studies have investigated the relationship between street centrality and land use patterns or commercial activities at interurban or intraurban scales. We considered Shichahai in this study to determine if street centrality applied at the street scale and if the street network was the only factor influencing the selection of store location. First, the nearest neighbor index, nearest neighbor hierarchical spatial cluster(NNHSC), and kernel density estimation(KDE) methods were used to provide baseline spatial distributions of commercial stores. Second, urban network analysis(UNA) tools were used to measure the street centrality indices under two conditions, with and without the weighting of cultural relics calculated by a principal component analysis(PCA). Finally, both store locations and centrality values at nodes were transformed to one unit(raster pixel) for a correlation analysis.The results showed that three of the four store types were clustered and had their own hotspots that were mostly located in the eastern and central parts of city blocks. The most momentous findings were determined from the street centrality indices. Among the three store types with correlation coefficients above 0.5, all centrality indices with landmark weighting, except straightness, had higher correlations,with closeness with landmark weighting having the highest correlation, followed by betweenness with landmark weighting. Therefore,we statistically concluded that street centrality could apply at the street scale and that the street network was not the only factor that influenced store location pattern, with landmarks also playing a significant role. The results provide guidance in determining the selection strategy for stores in a historic conservation area.
基金financed by the National Science Centre in Poland by project no.2017/27/B/HS4/01220。
文摘Rural areas in the K?odzko Region were subject to a long-term depopulation,marginalization,and long-lasting socio-economic decline since the 19th century.In recent years,however,the study area has been subject to a shift in socio-economic trends that show rural revival.The main goal of the research is to assess the actual role of tourism in socio-economic revival of rural areas in the K?odzko Region.To determine the dynamics of the tourism function development,statistical data were used and an inventory of tourism beds in accommodation facilities was conducted.The results show that there was a substantial development of the tourism function in the study area and its most intense scale was noted in the depopulating villages,as evidenced by the increase in the numbers of tourism facilities and numbers of tourism beds.Therefore,it can be concluded that the development of tourism contributed to the limitation of negative socioeconomic processes in the area and,in the case of some villages,even to the reversal of these trends,which might testify to the rural revival.Moreover,the improvement of the socio-economic situation is visible also in the villages that do not have significant tourist values but are in the neighbourhood of tourism hotspots.This observation might be important for forecasting future development and planning of rural areas.
文摘We introduce the concept of truncated states obtained via iterative processes (TSI) and study its statistical features, making an analogy with dynamical systems theory (DST). As a specific example, we have studied TSI for the doubling and the logistic functions, which are standard functions in studying chaos. TSI for both the doubling and logistic functions exhibit certain similar patterns when their statistical features are compared from the point of view of DST.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10575040 and 90503010.
文摘Taking the intensity-dependent coupling between atoms and cavity mode into account, we investigate a system consisting of N homogeneously broadened two-level atoms interacting with the field inside a single-mode Fabry- Perot cavity containing a nonlinear Kerr-like medium. We derive the steady-state bistable behaviour of the system, and further analyse in details the influence of several critical parameters on the bistable behaviour.
基金Supported by the National Key Basic Research Programme of China under Grant No 2005CB724500, and the National Natural Science Foundation of China under Grant Nos 60178016 and 10104002.
文摘We report the long time dynamical behaviour of ac Stark effect in a simple quantum model in which two level atoms interact with quantized coherent radiation field. A new phenomenon of periodic quantum collapse and revival of the ac Stark shift of energy level due to ac Stark effect is expressed accurately by analysing the phase of transition probability amplitude. The analytic prediction is confirmed by the numerical results.
基金Project supported by the National Natural Science Foundation of China (Grant No 10865006)
文摘The nonequilibrium phase transition and the symmetry revival induced by time delay in a bistable system are investigated. The stationary probability distribution function (SPDF) of the bistable system with time delay and correlated noises are calculated by an analytical method and stochastic simulation respectively. The analytical and simulative results indicate that: (1) There is a certain value of λ(λ denotes the strength of correlations between the multiplicative and additive noises) to make the SPDF symmetric under some time delay; however, above or below the given value, the symmetry will be broken; (2) With the monotonic change of λ, the unimodal peak structure of SPDF becomes bimodal at the beginning, then it becomes unimodal again; this means that there is a reentrance phenomenon in the process; (3) There is a critical value of delay time, which makes the lower peak of SPDF equal to the higher one under the critical condition. This means that the symmetry revival phenomenon emerges.
文摘AD = 1 position-dependent mass approach to constructing nonlinear quantum states for a modified Coulomb potential is used to generate Gazeau–Klauder coherent states. It appears that their energy eigenvalues are scaled down by the quantum number and the nonlinearity coefficient. We study the basic properties of these states, which are found to be undefined on the whole complex plane, and some details of their revival structure are discussed.
基金Project supported by the Postdoctoral Applied Research Program of Qingdao(Grant No.62350079311135)the National Natural Science Foundation of China(Grant Nos.11704053 and 11947057)the Science and Technology Project Affiliated to the Education Department of Chongqing Municipality(Grant No.KJQN201800629)。
文摘We investigate interference properties of a trapped atom interferometer where two symmetric optical dipole traps(ODTs)act as the atomic wave-packets splitter and combiner with internal state labelling.After the preparation of initial superposition states,the atomic wave-packet is adiabatically split and moves into two spatially separate asymmetric ODTs.The atomic wave-packets in two ODTs are then adiabatically recombined after a duration of free evolving in traps,completing the interference cycle of this atom interferometer.We show that the interferogram exhibits a series of periodic revivals in interference visibility.Furthermore,the revival period decreases as the asymmetry of two dipole potentials increases.By introducing an echo sequence to the interferometer,we show that while the echo effect is not influenced by the asymmetry of the two ODTs,the onset of periodic revivals changes by the echo sequence.Our study provides an effective method to cancel or compensate the phase shift caused by position and time correlated force.
基金The project supported by the 973 Program under Grant No.2006CB921106National Natural Science Foundation of China under Grant Nos.10325521,60433050,60635040the SRFDP Program of Education Ministry of China under Grant No.20060003048
文摘The Hamiltonian of a superconducting charge qubit with a configuration of dc SQUID contains an interac-tion between the LC oscillator part and charge qubit.This interaction may leads to quantum state collapse and revivalwhich degrades the charge qubits and leads to serious decoherence.An analysis shows that the existing charge qubitparameters do not lead to this phenomenon,which is very good for the superconducting charge
基金Supported by the National Natural Science Foundation of China(41972157)Natural Science Foundation of Heilongjiang Province,China(TD2019D001)+1 种基金Natural Science Foundation of Heilongjiang Province,China(QC2018041)PetroChina Major Project of Ministry of Science and Technology(2019D-0706)。
文摘An evaluation system of hydrocarbon-bearing availability of fault traps was established based on the comprehensive analysis of fault segment growth history,fine reservoir anatomy and geochemistry tracing,with the Qikou sag in the Bohai Bay Basin as target area.The displacement/separation transform and displacement gradient method were used to prove the interpretation reliability of fault traps.The method of maximum throw subtraction was used to recover the history of fault growth and determine the availability of the forming period of fault traps.Based on the quantitative relationship between shale gouge ratio and cross-fault pressure difference of known reservoirs in southern Qikou sag,the critical shale gouge ratio of fault lateral sealing was calculated at 20%,and the quantitative evaluation chart based on the relationship of"fault throw–sand-formation ratio and hydrocarbon column height"was constructed.Based on the results of reservoir fine anatomy and quantitative fluorescence tracing test shale smear factor method is suitable for evaluating the vertical sealing of faults in the caprock of the middle submember of first member of Paleogene Shahejie Formation,and the shale smear factor critical value is 3.5.The juxtaposition thickness method is suitable for evaluating vertical sealing of faults in the caprock of the second member of Paleogene Dongying Formation,and the critical juxtaposition thickness of fault is 70–80 m.By combining four factors,the availability of fault trap interpretation,the availability of the forming period of fault trap,the availability of fault lateral sealing and the availability of fault vertical sealing,the comprehensive evaluation chart on hydrocarbon-bearing availability of fault traps in Qikou sag has been established,which provides a reasonable basis for risk assessment of fault traps.
文摘On March 6,2009,Russian Foreign Minister Sergei Lavrov and U.S.Secretary of State Hillary Clinton pressed together the"reset button"in Geneva,signifying that both sides wanted to thaw their bilateral ties since it hit an all-time low over the Russia-Georgia conflict in August,2008.Although there were some positive signs in improving US-Russian ties,bilateral relations are hard to revive in the near future.