An isospectral problem with four potentials is discussed. The corresponding hierarchy of nonlinearevolution equations is derived. It is shown that the AKNS, Levi, D-AKNS hierarchies and a new oneare reductions of the... An isospectral problem with four potentials is discussed. The corresponding hierarchy of nonlinearevolution equations is derived. It is shown that the AKNS, Levi, D-AKNS hierarchies and a new oneare reductions of the above hierarchy. In each case the relevant Hamiltonian form is established bymaking use of the trase identity.展开更多
The Global Stratotype Section and Point （GSSP） for the boundary between the Capitanian and Wuchiapingian stages, also the boundary between the Guadalupian and Lopingian Series is defined at the First Appearance Dat...The Global Stratotype Section and Point （GSSP） for the boundary between the Capitanian and Wuchiapingian stages, also the boundary between the Guadalupian and Lopingian Series is defined at the First Appearance Datum （FAD） of the conodont Clarkina postbitteri postbitteri at the base of Bed 6k in the Penglaitan Section along the Hongshui River in Guangxi Province, South China. This point is within a chronomorphocline from Clarkina postbitteri hongshuiensis to C. dukouensis and nearly coincides with the Middle-Upper Absaroka Megasequence boundary and as such is documented within a continuously deposited carbonate lowstand succession with deep-water facies of the Maokou Formation below and deep-water facies of the Heshan Formation above. Furthermore, this point also coincides with a major extinction of various Permian fossils including corals, fusulinaceans, ammonoids and brachiopods. The proximity to an apparently global major sequence boundary and extinction event will serve as a means of correlation of this GSSP into other regions in which the defining taxon is not present because of profound provincialism during the Middle and Upper Permian. Carbon isotopic trends and magnetostratigraphic signatures are also provided to help correlate this GSSP into other regions, including those with continental facies successions. The Tieqiao Section near the county town of Laibin is also described as a supplementary reference section.展开更多
Research into the suppressive activity of CD4＋FoxP3＋ T regulatory cells （Treg） has defined a sublineage of CD4＋ cells that contribute to self-tolerance and resistance to autoimmune disease. Much less attention ha...Research into the suppressive activity of CD4＋FoxP3＋ T regulatory cells （Treg） has defined a sublineage of CD4＋ cells that contribute to self-tolerance and resistance to autoimmune disease. Much less attention has been given to the potential contribution of regulatory sublineages of CD8＋ cells. Analysis of a small fraction of CD8＋ cells that target autoreactive CD4＋ cells through recognition of the MHC class Ib molecule Qa-1 in mouse and HLA-E in human has revitalized interest in CD8＋ Treg. Here we summarize recent progress and future directions of research into the role of this CD8＋ sublineage in resistance to autoimmune disease. Cellular ＆ Molecular Immunology. 2008; 5（6）：401-406.展开更多
The principle and technique were reported here to produce lignin-based sand stabilizing material （LSSM） using extracted lignin from black liquor of straw paper mills. Field tests using LSSM to stabilize and green sa...The principle and technique were reported here to produce lignin-based sand stabilizing material （LSSM） using extracted lignin from black liquor of straw paper mills. Field tests using LSSM to stabilize and green sand dunes were started in 2002. The field experiment was carded out in August 2005 when the newly formed plant community was 3 years old. The results from the comprehensive field experiment demonstrated that unlike polyvinyl acetate or foamed asphalt commonly used for dune stabilization, LSSM was plant- friendly material and could be used in combination with seeding and planting of desert species. With the help of LSSM, the desert species （i.e., Agriophyllum squarrosum （L.） Moq. and Artemisia desertorum Spreng. etc.） could be used to form community in 2-3 yeas and to stabilize sand dune effectively. The newly formed community was sustainable under an extremely dry climate condition. The organic matter and total nitrogen in the soil increased significantly as the community were formed, while the change in P and K contents in the soil was negligible.展开更多
Coumarins belong to a diverse group of naturally occurring non-nutrient phytochemicals known as benzo-α- pyrones. In this study, esculetin, a 6,7-dihydroxy derivative of coumarin with pleiotropic biological activitie...Coumarins belong to a diverse group of naturally occurring non-nutrient phytochemicals known as benzo-α- pyrones. In this study, esculetin, a 6,7-dihydroxy derivative of coumarin with pleiotropic biological activities, was found to have no significant cytotoxic effect on normal murine macrophages, but it could increase the in vivo migration of the thioglycollate-elicited macrophages in a dose-dependent manner. Moreover, esculetin significantly increased the endocytic activity, and augmented the nitric oxide production and iNOS gene expression in LPS-treated macrophages. In addition, in vivo administration of esculetin into mice was shown to increase the mitogenesis of splenic lymphocytes towards Con A and LPS stimulations, and induced the LAK activity of splenic lymphocytes. Collectively, our results indicate that esculetin could exert immunomodulatory effects on murine macrophages and lymphocytes, both in vitro and in vivo, and this might be one of the possible mechanisms by which coumarins can exert their chemopreventive and anti-tumor activities in vivo. Cellular ＆ Molecular Immunology. 2005;2（3）： 181-188.展开更多
In this paper, the existence and smoothness of the collision local time are proved for two independent fractional Brownian motions, through L^2 convergence and Chaos expansion. Furthermore, the regularity of the colli...In this paper, the existence and smoothness of the collision local time are proved for two independent fractional Brownian motions, through L^2 convergence and Chaos expansion. Furthermore, the regularity of the collision local time process is studied.展开更多
This paper investigates a multi-period mean-variance portfolio selection with regime switching and uncertain exit time. The returns of assets all depend on the states of the stochastic market which are assumed to foll...This paper investigates a multi-period mean-variance portfolio selection with regime switching and uncertain exit time. The returns of assets all depend on the states of the stochastic market which are assumed to follow a discrete-time Markov chain. The authors derive the optimal strategy and the efficient frontier of the model in closed-form. Some results in the existing literature are obtained as special cases of our results.展开更多
China＇ s state planned land use system, including regulations such as setting planned quotas for land use, basic cropland preservation, and pursuing a balance between the conversion of arable land into non-agricultur...China＇ s state planned land use system, including regulations such as setting planned quotas for land use, basic cropland preservation, and pursuing a balance between the conversion of arable land into non-agricultural use and the supplement of new agricultural land, has substantially constrained the economic growth of industrial provinces in China. This article explores the innovative reforms adopted by Zhejiang Province through land development rights （LDR） transfer within a locality and LDR trading across localities. We argue that there is a ＂Zhejiang model of LDR transferring and trading,＂ which, we believe, has significant implications not only for fostering an efficiency-enhancing market for land development rights and agricultural land preservation, but also for optimal use of land and a more balanced regional development. One important policy issue relating to China＇s rural land system is that under China＇ s land requisition system, farmers are usually under compensated for urban land-taking.展开更多
To determine the regulatory effects of estrogen and cytokine IL-6 and IL-8 on the growth of epithelial ovarian cancer （OVCA）, we first examined the status of estrogen receptors （ERα and ERβ）, IL-6 receptor （IL...To determine the regulatory effects of estrogen and cytokine IL-6 and IL-8 on the growth of epithelial ovarian cancer （OVCA）, we first examined the status of estrogen receptors （ERα and ERβ）, IL-6 receptor （IL-6Rα and gp130）, and IL-8 receptor （IL-8RA and IL-8RB） on five epithelial OVCA cell lines by semiquantitative RT-PCR and Western blot analysis. Results showed that the expressions of these receptors were variable on the five cells. Those OVCA ceUs expressing the receptors were selected to study related molecular mechanism. MTT assay was performed to observe the effects of 17β-estradiol （E2）, IL-6 and IL-8 on cell proliferation. We discovered that E2 markedly promoted the proliferation of CAOV-3 and OVCAR-3 cell in a time- and dose-dependent manner. Tamoxifen （Txf）, an ER inhibitor, completely blocked the proliferation of the E2-induced cells, and IL-6- or/and IL-8-neutralizing antibody only showed partially blocking activity. IL-6 and IL-8 were able to significantly stimulate CAOV-3 and OVCAR-3 cell proliferation in a time- and dose-dependent manner, which had a potential synergistic effect on CAOV-3 cells but not on OVCAR-3 cells. The cell proliferation induced by these two cytokines was abolished completely by their specific neutralizing antibodies, partially by Txf, but not by unrelated goat IgG. Taken together, our results suggested that estrogen, IL-6 and IL-8 could modulate OVCA growth by forming a reciprocal cascade with amplifying effect.展开更多
Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on t...Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on this sport, no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance. The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers. Methods： Four electronic databases were searched using relevant subject headings and keywords. Only original research articles published in peerreviewed journals and the English language and addressing performance, biomechanics, physiology, and anthropometry of XCS racers were reviewed. Results： All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies. None of the articles involved the use of an experimental design. Furthermore, potential changes in external conditions （e.g.,weather, ski properties） were not taken into consideration. A comparable number of studies focused on the skating or classical technique. In most cases, positive pacing was observed, with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy. The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies, which was not the case for cycle rate. In general, uphill performance was closely related to overall race performance, with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers. Moreover, pacing was coupled to the selection and distribution of technique during a race, with faster skiers employing more double poling and kick double poling, less diagonal stride, and more V2 （double dance） than V1 （single dance） skating across a rac展开更多
Exercise training is beneficial to the cardiovascular system. MicroRNAs （miRNAs, miRs） are a class of conserved non-coding RNAs and play a wide-ranging role in the regulation of eukaryotic gene expression. Exercise ...Exercise training is beneficial to the cardiovascular system. MicroRNAs （miRNAs, miRs） are a class of conserved non-coding RNAs and play a wide-ranging role in the regulation of eukaryotic gene expression. Exercise training alters the expression levels of large amounts ofmiRNAs in the heart. In addition, circulating miRNAs appear to be regulated by exercise training. In this review, we will summarize recent advances in the regulation of miRNAs during physical exercise intervention in various cardiovascular diseases, including pathologic cardiac hypertrophy, myocardial fibrosis, ischemia-reperfusion injury, myocardial infarction, and heart failure. The regulatory role of circulating miRNAs after exercise training was also reviewed. In conclusion, miRNAs might be a valuable target for treatment of cardiovascular diseases and have great potential as biomarkers for assessment of physical performance.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.展开更多
T lymphocytes with dedicated suppressor function(Treg)play a crucial role in the homeostatic control of immunity in the periphery.Several Treg phenotypes have now been identified in the CD4 and CD8 T cell populations,...T lymphocytes with dedicated suppressor function(Treg)play a crucial role in the homeostatic control of immunity in the periphery.Several Treg phenotypes have now been identified in the CD4 and CD8 T cell populations, suggesting their down-regulatory function in both human and animal models of autoimmunity,transplantation and tumor immunity.Here we will focus on the CD8 Treg population and their ability to specifically inhibit a pathogenic autoimmune response.This review will detail the current advances in the knowledge of CD8 Treg in the context of antigen specificity,phenotype,MHC restriction,mechanism of action,and priming.Cellular & Molecular Immunology.2005;2(1):11-19.展开更多
This work focuses on the relationship between flexibility of molecular chains and thermal properties of polyurethane elastomer（PUE）, which laid the foundation of further research about how to improve thermal propert...This work focuses on the relationship between flexibility of molecular chains and thermal properties of polyurethane elastomer（PUE）, which laid the foundation of further research about how to improve thermal properties of PUE. A series of PUE samples with different flexibility of molecular chains was prepared by using 1,4-butanediol（1,4-BDO）/bisphenol-a（BPA） blends with different mole ratios including9/1, 8/2, 7/3, 6/4 and 5/5. As comparison, PUE extended with pure 1,4-BDO and BPA was also synthesized.These samples were characterized by differential scanning calorimetry（DSC）, thermogravimetric analysis（TGA）, dynamic mechanical analysis（DMA）, etc. The results showed that with the decrease in flexibility of molecular chains the glass transition temperature（Tg） increased and low-temperature properties became worse. Besides, all samples had a certain degree of microphase separation, and soft segments in some samples were crystallized, i.e. the decreasing flexibility of molecular chains led to the impossibility of chains tightly packing and crystalline domains forming so that the degree of microphase separation decreased and the thermal properties became worse.展开更多
The biathlon, an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship, entails considerable physiological demands, as well as fine motor control while shooting after intense exercise ...The biathlon, an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship, entails considerable physiological demands, as well as fine motor control while shooting after intense exercise and under mental pressure. Although much of our knowledge about cross-country skiing is probably also applicable to the biathlon, carrying the rifle and shooting under stress make this discipline somewhat unique. The present review summarizes and examines the scientific literature related to biathlon performance, with a focus on physiological and biomechanical factors and shooting technique, as well as psychophysiological aspects of shooting performance. We conclude with suggestions for future research designed to extend our knowledge about the biathlon, which is presently quite limited.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.展开更多
Purpose： The aims of this study were to assess differences of limb symmetry index （LSI） in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related pe...Purpose： The aims of this study were to assess differences of limb symmetry index （LSI） in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related performance levels and to prospectively assess limb differences as a possible risk factor for traumatic and overuse injury in youth ski racers. Methods： The study （Study 1） included 285 high-level competitive ski racers （125 females, 160 males） of 3 age-related performance levels and based on the school system： 95 youth （10-14 years, secondary modem school）, 107 adolescent （15-19 years, grammar school）, and 83 elite athletes （20-34 years）. To investigate the second aim （Study 2）, 67 of the 95 youth athletes were included and any traumatic or overuse injuries were prospectively recorded over 2 seasons. All athletes performed 4 unilateral tests （strength related： one-leg counter movement jump （OL-CMJ） and one-leg isometric/isokinetic press strength test （OL-ILS）; coordination related： one-leg stability test （OL-ST） and one-leg speedy jump test （OL-SJ））. The LSI was calculated by dividing the dominant leg by the nondominant leg and multiplying by 100. Kruskal-Wallis H tests and binary logistic regression analyses were conducted. Results： There were significant differences between the LSI of the 3 age-related performance-level groups only in the strength-related tests： the OL-CMJ （X^2（2, 285） = 9.09; p = 0.01） and the OL-ILS （X^2（2,285） = 14.79; p 〈 0.01）. The LSI for OL-ILS was found to be a significant risk factor for traumatic injury in youth ski racers （Wald = 7.08; p 〈 0.01）. No significant risk factors were found for overuse injuries. Conclusion： Younger athletes display slightly greater LSI values only in the strength-related tests. The cut-off value of limb differences of 〈 10% for return to sport decisions seems to be appropriate for elite athletes, but for youth and adolescent athletes it has to be critically d展开更多
In recent years,photocatalytic technology,driven by solar energy,has been extensively investigated to ease energy crisis and environmental pollution.Nevertheless,efficiency and stability of photocatalysts are still un...In recent years,photocatalytic technology,driven by solar energy,has been extensively investigated to ease energy crisis and environmental pollution.Nevertheless,efficiency and stability of photocatalysts are still unsatisfactory.To address these issues,design of advanced photocatalysts is important.Cadmium sulphide(CdS)nanomaterials are one of the promising photocatalysts.Among them,hollow-structured CdS,featured with enhanced light absorption ability,large surface area,abundant active sites for redox reactions,and reduced diffusion distance of photogenerated carriers,reveals a broad application prospect.Herein,main synthetic strategies and formation mechanism of hollow CdS photocatalysts are summarized.Besides,we comprehensively discuss the current development of hollow-structured CdS nanomaterials in photocatalytic applications,including H2 production,CO2 reduction and pollutant degradation.Finally,brief conclusions and perspectives on the challenges and future directions for hollow CdS photocatalysts are proposed.展开更多
In this paper,the authors obtain the boundedness of the fractional integral operators with variable kernels on the variable exponent generalized weighted Morrey spaces and the variable exponent vanishing generalized w...In this paper,the authors obtain the boundedness of the fractional integral operators with variable kernels on the variable exponent generalized weighted Morrey spaces and the variable exponent vanishing generalized weighted Morrey spaces.And the corresponding commutators generated by BMO function are also considered.展开更多
In this paper,the authors investigate three aspects of statistical inference for the partially linear regression models where some covariates are measured with errors.Firstly, a bandwidth selection procedure is propos...In this paper,the authors investigate three aspects of statistical inference for the partially linear regression models where some covariates are measured with errors.Firstly, a bandwidth selection procedure is proposed,which is a combination of the differencebased technique and GCV method.Secondly,a goodness-of-fit test procedure is proposed, which is an extension of the generalized likelihood technique.Thirdly,a variable selection procedure for the parametric part is provided based on the nonconcave penalization and corrected profile least squares.Same as＂Variable selection via nonconcave penalized likelihood and its oracle properties＂（J.Amer.Statist.Assoc.,96,2001,1348-1360）,it is shown that the resulting estimator has an oracle property with a proper choice of regularization parameters and penalty function.Simulation studies are conducted to illustrate the finite sample performances of the proposed procedures.展开更多
The fidelity of teleportation of continuous quantum variables can be improved by tuning the local displacement gain. We investigate the optimization of the fidelity for the teleportation of Schrodinger cat states, and...The fidelity of teleportation of continuous quantum variables can be improved by tuning the local displacement gain. We investigate the optimization of the fidelity for the teleportation of Schrodinger cat states, and of coherent states. It is found that the gain corresponding to the maximum fidelity is not equal to one for the two input states in the case of the small squeezing degree of the entanglement resource, while unity displacement gain is the best choice for teleporting arbitrary quantum states in the case of large squeezing.展开更多
A proper edge coloring of a graph G is called adjacent vertex-distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the coloring set of edges incident with u is not equal to the coloring set of ...A proper edge coloring of a graph G is called adjacent vertex-distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the coloring set of edges incident with u is not equal to the coloring set of edges incident with v, where uv∈ E（G）. The adjacent vertex distinguishing acyclic edge chromatic number of G, denoted by X＇Aa（G）, is the minimal number of colors in an adjacent vertex distinguishing acyclic edge coloring of G. If a graph G has an adjacent vertex distinguishing acyclic edge coloring, then G is called adjacent vertex distinguishing acyclic. In this paper, we obtain adjacent vertex-distinguishing acyclic edge coloring of some graphs and put forward some conjectures.展开更多
基金The project supported by National Natural Science Foundation Committeethrough Nankai Institute of Mathematics
文摘 An isospectral problem with four potentials is discussed. The corresponding hierarchy of nonlinearevolution equations is derived. It is shown that the AKNS, Levi, D-AKNS hierarchies and a new oneare reductions of the above hierarchy. In each case the relevant Hamiltonian form is established bymaking use of the trase identity.
文摘The Global Stratotype Section and Point （GSSP） for the boundary between the Capitanian and Wuchiapingian stages, also the boundary between the Guadalupian and Lopingian Series is defined at the First Appearance Datum （FAD） of the conodont Clarkina postbitteri postbitteri at the base of Bed 6k in the Penglaitan Section along the Hongshui River in Guangxi Province, South China. This point is within a chronomorphocline from Clarkina postbitteri hongshuiensis to C. dukouensis and nearly coincides with the Middle-Upper Absaroka Megasequence boundary and as such is documented within a continuously deposited carbonate lowstand succession with deep-water facies of the Maokou Formation below and deep-water facies of the Heshan Formation above. Furthermore, this point also coincides with a major extinction of various Permian fossils including corals, fusulinaceans, ammonoids and brachiopods. The proximity to an apparently global major sequence boundary and extinction event will serve as a means of correlation of this GSSP into other regions in which the defining taxon is not present because of profound provincialism during the Middle and Upper Permian. Carbon isotopic trends and magnetostratigraphic signatures are also provided to help correlate this GSSP into other regions, including those with continental facies successions. The Tieqiao Section near the county town of Laibin is also described as a supplementary reference section.
基金supported in part by research grants from the NIH (AI037562)National Multiple Sclerosis Society and a gift from the Schecter Family Research Foundation to HC LL is a Claudia Adams Barr Investigator and NIH NRSA Fellow (T32 AI07386)
文摘Research into the suppressive activity of CD4＋FoxP3＋ T regulatory cells （Treg） has defined a sublineage of CD4＋ cells that contribute to self-tolerance and resistance to autoimmune disease. Much less attention has been given to the potential contribution of regulatory sublineages of CD8＋ cells. Analysis of a small fraction of CD8＋ cells that target autoreactive CD4＋ cells through recognition of the MHC class Ib molecule Qa-1 in mouse and HLA-E in human has revitalized interest in CD8＋ Treg. Here we summarize recent progress and future directions of research into the role of this CD8＋ sublineage in resistance to autoimmune disease. Cellular ＆ Molecular Immunology. 2008; 5（6）：401-406.
基金supported by the National Natural Science Foundation of China (No. 40675040, 30771687, and90302015)the National Basic Research Program of China (No. 2006CB400505)
文摘The principle and technique were reported here to produce lignin-based sand stabilizing material （LSSM） using extracted lignin from black liquor of straw paper mills. Field tests using LSSM to stabilize and green sand dunes were started in 2002. The field experiment was carded out in August 2005 when the newly formed plant community was 3 years old. The results from the comprehensive field experiment demonstrated that unlike polyvinyl acetate or foamed asphalt commonly used for dune stabilization, LSSM was plant- friendly material and could be used in combination with seeding and planting of desert species. With the help of LSSM, the desert species （i.e., Agriophyllum squarrosum （L.） Moq. and Artemisia desertorum Spreng. etc.） could be used to form community in 2-3 yeas and to stabilize sand dune effectively. The newly formed community was sustainable under an extremely dry climate condition. The organic matter and total nitrogen in the soil increased significantly as the community were formed, while the change in P and K contents in the soil was negligible.
文摘Coumarins belong to a diverse group of naturally occurring non-nutrient phytochemicals known as benzo-α- pyrones. In this study, esculetin, a 6,7-dihydroxy derivative of coumarin with pleiotropic biological activities, was found to have no significant cytotoxic effect on normal murine macrophages, but it could increase the in vivo migration of the thioglycollate-elicited macrophages in a dose-dependent manner. Moreover, esculetin significantly increased the endocytic activity, and augmented the nitric oxide production and iNOS gene expression in LPS-treated macrophages. In addition, in vivo administration of esculetin into mice was shown to increase the mitogenesis of splenic lymphocytes towards Con A and LPS stimulations, and induced the LAK activity of splenic lymphocytes. Collectively, our results indicate that esculetin could exert immunomodulatory effects on murine macrophages and lymphocytes, both in vitro and in vivo, and this might be one of the possible mechanisms by which coumarins can exert their chemopreventive and anti-tumor activities in vivo. Cellular ＆ Molecular Immunology. 2005;2（3）： 181-188.
基金the National Natural Science Foundation of China(No. 10471003).
文摘In this paper, the existence and smoothness of the collision local time are proved for two independent fractional Brownian motions, through L^2 convergence and Chaos expansion. Furthermore, the regularity of the collision local time process is studied.
基金This research is supported by the National Science Foundation for Distinguished Young Scholars under Grant No. 70825002, the National Natural Science Foundation of China under Grant No. 70518001, and the National Basic Research Program of China 973 Program, under Grant No. 2007CB814902.
文摘This paper investigates a multi-period mean-variance portfolio selection with regime switching and uncertain exit time. The returns of assets all depend on the states of the stochastic market which are assumed to follow a discrete-time Markov chain. The authors derive the optimal strategy and the efficient frontier of the model in closed-form. Some results in the existing literature are obtained as special cases of our results.
基金the China National Science Foundation (70633002)the Chinese Ministry of Science+3 种基金Technology Key Technologies R&D Program (2006 BAJI1B06)the Chinese Academy of Science Innovation project (KSCX2-YW-N-039)the Lincoln Institute of LPolicy for generous financial support
文摘China＇ s state planned land use system, including regulations such as setting planned quotas for land use, basic cropland preservation, and pursuing a balance between the conversion of arable land into non-agricultural use and the supplement of new agricultural land, has substantially constrained the economic growth of industrial provinces in China. This article explores the innovative reforms adopted by Zhejiang Province through land development rights （LDR） transfer within a locality and LDR trading across localities. We argue that there is a ＂Zhejiang model of LDR transferring and trading,＂ which, we believe, has significant implications not only for fostering an efficiency-enhancing market for land development rights and agricultural land preservation, but also for optimal use of land and a more balanced regional development. One important policy issue relating to China＇s rural land system is that under China＇ s land requisition system, farmers are usually under compensated for urban land-taking.
基金supported by grants from National Basic Research Priorities 973 Program(No.2003CCA04300)the National Natural Science Foundation of China(No.30471962)Program for New Century Excellent Talents in University(NCET-04-0245).
文摘To determine the regulatory effects of estrogen and cytokine IL-6 and IL-8 on the growth of epithelial ovarian cancer （OVCA）, we first examined the status of estrogen receptors （ERα and ERβ）, IL-6 receptor （IL-6Rα and gp130）, and IL-8 receptor （IL-8RA and IL-8RB） on five epithelial OVCA cell lines by semiquantitative RT-PCR and Western blot analysis. Results showed that the expressions of these receptors were variable on the five cells. Those OVCA ceUs expressing the receptors were selected to study related molecular mechanism. MTT assay was performed to observe the effects of 17β-estradiol （E2）, IL-6 and IL-8 on cell proliferation. We discovered that E2 markedly promoted the proliferation of CAOV-3 and OVCAR-3 cell in a time- and dose-dependent manner. Tamoxifen （Txf）, an ER inhibitor, completely blocked the proliferation of the E2-induced cells, and IL-6- or/and IL-8-neutralizing antibody only showed partially blocking activity. IL-6 and IL-8 were able to significantly stimulate CAOV-3 and OVCAR-3 cell proliferation in a time- and dose-dependent manner, which had a potential synergistic effect on CAOV-3 cells but not on OVCAR-3 cells. The cell proliferation induced by these two cytokines was abolished completely by their specific neutralizing antibodies, partially by Txf, but not by unrelated goat IgG. Taken together, our results suggested that estrogen, IL-6 and IL-8 could modulate OVCA growth by forming a reciprocal cascade with amplifying effect.
文摘Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on this sport, no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance. The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers. Methods： Four electronic databases were searched using relevant subject headings and keywords. Only original research articles published in peerreviewed journals and the English language and addressing performance, biomechanics, physiology, and anthropometry of XCS racers were reviewed. Results： All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies. None of the articles involved the use of an experimental design. Furthermore, potential changes in external conditions （e.g.,weather, ski properties） were not taken into consideration. A comparable number of studies focused on the skating or classical technique. In most cases, positive pacing was observed, with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy. The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies, which was not the case for cycle rate. In general, uphill performance was closely related to overall race performance, with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers. Moreover, pacing was coupled to the selection and distribution of technique during a race, with faster skiers employing more double poling and kick double poling, less diagonal stride, and more V2 （double dance） than V1 （single dance） skating across a rac
基金supported by grants from the National Natural Science Foundation of China(81722008,91639101,and81570362 to JX and 81800358 to LW)the Innovation Program of Shanghai Municipal Education Commission(2017-01-07-00-09-E00042 to JX)+1 种基金the Science and TechnologyCommission of Shanghai Municipality(17010500100 to JX)the development fund for Shanghai talents(to JX)
文摘Exercise training is beneficial to the cardiovascular system. MicroRNAs （miRNAs, miRs） are a class of conserved non-coding RNAs and play a wide-ranging role in the regulation of eukaryotic gene expression. Exercise training alters the expression levels of large amounts ofmiRNAs in the heart. In addition, circulating miRNAs appear to be regulated by exercise training. In this review, we will summarize recent advances in the regulation of miRNAs during physical exercise intervention in various cardiovascular diseases, including pathologic cardiac hypertrophy, myocardial fibrosis, ischemia-reperfusion injury, myocardial infarction, and heart failure. The regulatory role of circulating miRNAs after exercise training was also reviewed. In conclusion, miRNAs might be a valuable target for treatment of cardiovascular diseases and have great potential as biomarkers for assessment of physical performance.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.
文摘T lymphocytes with dedicated suppressor function(Treg)play a crucial role in the homeostatic control of immunity in the periphery.Several Treg phenotypes have now been identified in the CD4 and CD8 T cell populations, suggesting their down-regulatory function in both human and animal models of autoimmunity,transplantation and tumor immunity.Here we will focus on the CD8 Treg population and their ability to specifically inhibit a pathogenic autoimmune response.This review will detail the current advances in the knowledge of CD8 Treg in the context of antigen specificity,phenotype,MHC restriction,mechanism of action,and priming.Cellular & Molecular Immunology.2005;2(1):11-19.
基金supported financially by the National Natural Science Foundation of China (Grant No. 51372200)Program for New Century Excellent Talents in University of Ministry of Education of China (Grant No. NCET-12-1045)+2 种基金Special Program for local serving from Education Department of Shaanxi Provincial Government (Grant No. 2013JC19)Program for Innovation Team in Xi’an University of Technology (Grant No. 108-25605T401)Ph.D. Innovation Fund Projects of Xi’an University of Technology (Fund No. 310-252071501)
文摘This work focuses on the relationship between flexibility of molecular chains and thermal properties of polyurethane elastomer（PUE）, which laid the foundation of further research about how to improve thermal properties of PUE. A series of PUE samples with different flexibility of molecular chains was prepared by using 1,4-butanediol（1,4-BDO）/bisphenol-a（BPA） blends with different mole ratios including9/1, 8/2, 7/3, 6/4 and 5/5. As comparison, PUE extended with pure 1,4-BDO and BPA was also synthesized.These samples were characterized by differential scanning calorimetry（DSC）, thermogravimetric analysis（TGA）, dynamic mechanical analysis（DMA）, etc. The results showed that with the decrease in flexibility of molecular chains the glass transition temperature（Tg） increased and low-temperature properties became worse. Besides, all samples had a certain degree of microphase separation, and soft segments in some samples were crystallized, i.e. the decreasing flexibility of molecular chains led to the impossibility of chains tightly packing and crystalline domains forming so that the degree of microphase separation decreased and the thermal properties became worse.
文摘The biathlon, an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship, entails considerable physiological demands, as well as fine motor control while shooting after intense exercise and under mental pressure. Although much of our knowledge about cross-country skiing is probably also applicable to the biathlon, carrying the rifle and shooting under stress make this discipline somewhat unique. The present review summarizes and examines the scientific literature related to biathlon performance, with a focus on physiological and biomechanical factors and shooting technique, as well as psychophysiological aspects of shooting performance. We conclude with suggestions for future research designed to extend our knowledge about the biathlon, which is presently quite limited.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. （http：//creativecommons.org/licenses/by-nc-nd/4.0/）.
文摘Purpose： The aims of this study were to assess differences of limb symmetry index （LSI） in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related performance levels and to prospectively assess limb differences as a possible risk factor for traumatic and overuse injury in youth ski racers. Methods： The study （Study 1） included 285 high-level competitive ski racers （125 females, 160 males） of 3 age-related performance levels and based on the school system： 95 youth （10-14 years, secondary modem school）, 107 adolescent （15-19 years, grammar school）, and 83 elite athletes （20-34 years）. To investigate the second aim （Study 2）, 67 of the 95 youth athletes were included and any traumatic or overuse injuries were prospectively recorded over 2 seasons. All athletes performed 4 unilateral tests （strength related： one-leg counter movement jump （OL-CMJ） and one-leg isometric/isokinetic press strength test （OL-ILS）; coordination related： one-leg stability test （OL-ST） and one-leg speedy jump test （OL-SJ））. The LSI was calculated by dividing the dominant leg by the nondominant leg and multiplying by 100. Kruskal-Wallis H tests and binary logistic regression analyses were conducted. Results： There were significant differences between the LSI of the 3 age-related performance-level groups only in the strength-related tests： the OL-CMJ （X^2（2, 285） = 9.09; p = 0.01） and the OL-ILS （X^2（2,285） = 14.79; p 〈 0.01）. The LSI for OL-ILS was found to be a significant risk factor for traumatic injury in youth ski racers （Wald = 7.08; p 〈 0.01）. No significant risk factors were found for overuse injuries. Conclusion： Younger athletes display slightly greater LSI values only in the strength-related tests. The cut-off value of limb differences of 〈 10% for return to sport decisions seems to be appropriate for elite athletes, but for youth and adolescent athletes it has to be critically d
基金supported by the National Key Research and Development Program of China(2018YFB1502001)the National Natural Science Foundation of China(51932007,51961135303,U1905215,21871217,and U1705251)+1 种基金National Innovation and Entrepreneurship Training Program for College Students(No.201910497026)the Innovative Research Funds of Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory(XHD2020-001).
文摘In recent years,photocatalytic technology,driven by solar energy,has been extensively investigated to ease energy crisis and environmental pollution.Nevertheless,efficiency and stability of photocatalysts are still unsatisfactory.To address these issues,design of advanced photocatalysts is important.Cadmium sulphide(CdS)nanomaterials are one of the promising photocatalysts.Among them,hollow-structured CdS,featured with enhanced light absorption ability,large surface area,abundant active sites for redox reactions,and reduced diffusion distance of photogenerated carriers,reveals a broad application prospect.Herein,main synthetic strategies and formation mechanism of hollow CdS photocatalysts are summarized.Besides,we comprehensively discuss the current development of hollow-structured CdS nanomaterials in photocatalytic applications,including H2 production,CO2 reduction and pollutant degradation.Finally,brief conclusions and perspectives on the challenges and future directions for hollow CdS photocatalysts are proposed.
基金supported by the National Natural Science Foundation of China(No.11561062)Natural Science Foundation of Gansu Province(21JR1RM337).
文摘In this paper,the authors obtain the boundedness of the fractional integral operators with variable kernels on the variable exponent generalized weighted Morrey spaces and the variable exponent vanishing generalized weighted Morrey spaces.And the corresponding commutators generated by BMO function are also considered.
文摘In this paper,the authors investigate three aspects of statistical inference for the partially linear regression models where some covariates are measured with errors.Firstly, a bandwidth selection procedure is proposed,which is a combination of the differencebased technique and GCV method.Secondly,a goodness-of-fit test procedure is proposed, which is an extension of the generalized likelihood technique.Thirdly,a variable selection procedure for the parametric part is provided based on the nonconcave penalization and corrected profile least squares.Same as＂Variable selection via nonconcave penalized likelihood and its oracle properties＂（J.Amer.Statist.Assoc.,96,2001,1348-1360）,it is shown that the resulting estimator has an oracle property with a proper choice of regularization parameters and penalty function.Simulation studies are conducted to illustrate the finite sample performances of the proposed procedures.
基金This project was supported by the National Fundamental Research Program (2001CB309300)the Innovation Funds from Chinese Academy of Sciences.
文摘The fidelity of teleportation of continuous quantum variables can be improved by tuning the local displacement gain. We investigate the optimization of the fidelity for the teleportation of Schrodinger cat states, and of coherent states. It is found that the gain corresponding to the maximum fidelity is not equal to one for the two input states in the case of the small squeezing degree of the entanglement resource, while unity displacement gain is the best choice for teleporting arbitrary quantum states in the case of large squeezing.
基金supported by NSFC of China (No. 19871036 and No. 40301037)Faculty Research Grant,Hong Kong Baptist University
文摘A proper edge coloring of a graph G is called adjacent vertex-distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the coloring set of edges incident with u is not equal to the coloring set of edges incident with v, where uv∈ E（G）. The adjacent vertex distinguishing acyclic edge chromatic number of G, denoted by X＇Aa（G）, is the minimal number of colors in an adjacent vertex distinguishing acyclic edge coloring of G. If a graph G has an adjacent vertex distinguishing acyclic edge coloring, then G is called adjacent vertex distinguishing acyclic. In this paper, we obtain adjacent vertex-distinguishing acyclic edge coloring of some graphs and put forward some conjectures.
