Carbonate pedofeatures were studied in details in a loess-paleosol pedocomplex near Kursk, in the central part of the European Plain. The soils studied included a modern Chernozem and five Pleistocene paleosols. Carbo...Carbonate pedofeatures were studied in details in a loess-paleosol pedocomplex near Kursk, in the central part of the European Plain. The soils studied included a modern Chernozem and five Pleistocene paleosols. Carbonate morphologies and distributions were described in the field. Various morphologies were sampled for further studies including micromorphology in thin sections and submicroscopic studies under a scanning electron microscope. The complex approach of investigation at macro-, micro-, and submicroscopic levels found that most of carbonate pedofeatures are secondary and multiphase. Many of them are related to cryogenic features. The general trend was of decreasing carbonate content in the older paleosols except for increased content in the 1St and 3rd paleosols. Most of carbonate morphologies are similar in the modern soil and paleosols, but pseudomycelium was found only in the modern Chernozem, while soft masses and impregnations are associated with the paleosols. Detailed study on carbonate attributes revealed their specific features in the modern soil and in paleosols. Veins have dissolution features under the modern environment and seem to reprecipitate in form of pseudomycelium. Coatings in paleosols at a depth of the Ist paleosol include specific fine tubes. Powdery soft masses and impregnations in the paleosols are strongly related to cryogenic fissures and paleopermafrost level. Under SEM they consist of tiny crystals, much smaller than in regular soft masses. Several types of hard concretions were identified：rounded, irregular and platy. Small concretions in the modern Chernozem have similar morphology and similar 14C-age as the rounded concretions of the upper paleosols. They are expected to represent the same generation of concretions. Platy concretions fill the bottom part of the large fissures. The 14C-age of hard concretions varies from 3310±80 yrs. B.P in the Ist paleosol up to 20 400 yrs. B.P. in the 3^rd. As a result we found the reflection of several wet-dry and cold-warm stages in carbonate morphologies and distributions. High variability of carbonates at macro-, micro- and submicroscopic levels indicates several generations and multiphase formation of carbonate pedofeatures in the loess-paleosol pedocomplex. Carbonate pedofeatures in the examined pedocomplex are more informative for the study of late Pleistocene and Holocene climatic cycles rather than characterization of a single paleosol.展开更多
双层宏蜂窝/小蜂窝异构网络不但能解决室内用户的覆盖问题,还可以大幅度降低网络能量消耗。但是,网络中的跨层和层间干扰会降低网络性能,高能效的无线资源分配和优化方法无疑将成为解决此问题的有效途径。首先,给出了一个移动云计算管...双层宏蜂窝/小蜂窝异构网络不但能解决室内用户的覆盖问题,还可以大幅度降低网络能量消耗。但是,网络中的跨层和层间干扰会降低网络性能,高能效的无线资源分配和优化方法无疑将成为解决此问题的有效途径。首先,给出了一个移动云计算管理框架。然后,针对无线单链路定义了空间传输效率,比较和分析了多种单链路效率度量的含义和数学性质,并针对基于LTE-A(long term evolution-advanced)的移动云计算接入网络,提出了一种高能效的无线资源管理算法。为了快速地达到最优解,设计了一个快速收敛的迭代算法。仿真分析说明此资源管理算法实现了移动云计算系统能量效率和吞吐量的高效折中。展开更多
Recent years,our research group focused the effects of G.polysaccharides,which are extracted from fruiting body of Ganoderma lucidum,on tumor evasion from immune surveillance.The immune system in patients with tumor o...Recent years,our research group focused the effects of G.polysaccharides,which are extracted from fruiting body of Ganoderma lucidum,on tumor evasion from immune surveillance.The immune system in patients with tumor often fails to control tumor growth because of deficient immunogenicity of tumor cells.Deficient major histocompatibility complex(MHC)classⅠ and costimulatory molecules on malignant cells partially results in tumor evasion since antigen bond MHC and costimulatory molecules provide two signals for T cell activation.Therefore,enhancement of MHC-Ⅰ and costimulatory molecules may favor restraint of the evasion.Our study found that G.polysaccharides can increase MHC classⅠ molecules such as H-2Kb and H-2Db as well as the costimulatory molecules B7-1 and B7-2 expression on B16F10 melanoma cells at both mRNA and protein levels,and can promote lymphocyte-mediated cytotoxicity.Tumour cells produce immune suppressive factors such as interleukin 10(IL-10),transforming growth factorβ1(TGF-β1)and vascular endothelial growth factor(VEGF)that suppress the function of immune cells or induce apoptosis of immune cells.Our study also found B16F10 cell culture supernatant(B16F10-CS)suppressed lymphocyte proliferation and perforin and granzyme B production in lymphocytes after induction with phytohemagglutinin(PHA),as well as lymphocyte proliferation in the mixed lymphocyte reaction.The suppression also associated with elevated levels of immunosuppressive IL-10,TGF-β1 and VEGF in B16F10-CS.Further,the production of IL-10,TGF-β1,and VEGF in B16F10 melanoma cells and lung carcinoma LA795 cells was suppressed by G.polysaccharides at both mRNA and protein levels.On the contrary,the production of IL-2,IFN-γand TNF-αin mononuclear lymphocytes was suppressed by B16F10-CF at both the mRNA and protein levels,whereas the suppression was ameliorated by G.polysaccharides.B16F10-CS was suppressive to the viability,phagocytic activity,NO production,TNF-αproduction and activity in peritoneal macrophages while G.polysaccharides had the antagonistic effects against this suppression.Then subsequently,the plasma of patients with lung cancer suppressed proliferation,CD69 expression,and perforin and granzyme B production in lymphocytes upon activation by PHA.However,these suppressive effects were reversed by G.polysaccharides.In conclusion,G.polysaccharides can improve the nature of B16F10 cells to activate lymphocytes and antagonize immunosuppression induced by B16F10-CS in lymphocytes and macrophages.These findings indicate that G.polysaccharides can restraint tumor evasion from immune surveillance,suggesting this potential value of G.polysaccharide to facilitate cancer immunotherapy.展开更多
基金supported by Russian Foundation for Basic Research (grants No 07-04-01146 and 06-05-65203)
文摘Carbonate pedofeatures were studied in details in a loess-paleosol pedocomplex near Kursk, in the central part of the European Plain. The soils studied included a modern Chernozem and five Pleistocene paleosols. Carbonate morphologies and distributions were described in the field. Various morphologies were sampled for further studies including micromorphology in thin sections and submicroscopic studies under a scanning electron microscope. The complex approach of investigation at macro-, micro-, and submicroscopic levels found that most of carbonate pedofeatures are secondary and multiphase. Many of them are related to cryogenic features. The general trend was of decreasing carbonate content in the older paleosols except for increased content in the 1St and 3rd paleosols. Most of carbonate morphologies are similar in the modern soil and paleosols, but pseudomycelium was found only in the modern Chernozem, while soft masses and impregnations are associated with the paleosols. Detailed study on carbonate attributes revealed their specific features in the modern soil and in paleosols. Veins have dissolution features under the modern environment and seem to reprecipitate in form of pseudomycelium. Coatings in paleosols at a depth of the Ist paleosol include specific fine tubes. Powdery soft masses and impregnations in the paleosols are strongly related to cryogenic fissures and paleopermafrost level. Under SEM they consist of tiny crystals, much smaller than in regular soft masses. Several types of hard concretions were identified：rounded, irregular and platy. Small concretions in the modern Chernozem have similar morphology and similar 14C-age as the rounded concretions of the upper paleosols. They are expected to represent the same generation of concretions. Platy concretions fill the bottom part of the large fissures. The 14C-age of hard concretions varies from 3310±80 yrs. B.P in the Ist paleosol up to 20 400 yrs. B.P. in the 3^rd. As a result we found the reflection of several wet-dry and cold-warm stages in carbonate morphologies and distributions. High variability of carbonates at macro-, micro- and submicroscopic levels indicates several generations and multiphase formation of carbonate pedofeatures in the loess-paleosol pedocomplex. Carbonate pedofeatures in the examined pedocomplex are more informative for the study of late Pleistocene and Holocene climatic cycles rather than characterization of a single paleosol.
文摘双层宏蜂窝/小蜂窝异构网络不但能解决室内用户的覆盖问题,还可以大幅度降低网络能量消耗。但是,网络中的跨层和层间干扰会降低网络性能,高能效的无线资源分配和优化方法无疑将成为解决此问题的有效途径。首先,给出了一个移动云计算管理框架。然后,针对无线单链路定义了空间传输效率,比较和分析了多种单链路效率度量的含义和数学性质,并针对基于LTE-A(long term evolution-advanced)的移动云计算接入网络,提出了一种高能效的无线资源管理算法。为了快速地达到最优解,设计了一个快速收敛的迭代算法。仿真分析说明此资源管理算法实现了移动云计算系统能量效率和吞吐量的高效折中。
文摘Recent years,our research group focused the effects of G.polysaccharides,which are extracted from fruiting body of Ganoderma lucidum,on tumor evasion from immune surveillance.The immune system in patients with tumor often fails to control tumor growth because of deficient immunogenicity of tumor cells.Deficient major histocompatibility complex(MHC)classⅠ and costimulatory molecules on malignant cells partially results in tumor evasion since antigen bond MHC and costimulatory molecules provide two signals for T cell activation.Therefore,enhancement of MHC-Ⅰ and costimulatory molecules may favor restraint of the evasion.Our study found that G.polysaccharides can increase MHC classⅠ molecules such as H-2Kb and H-2Db as well as the costimulatory molecules B7-1 and B7-2 expression on B16F10 melanoma cells at both mRNA and protein levels,and can promote lymphocyte-mediated cytotoxicity.Tumour cells produce immune suppressive factors such as interleukin 10(IL-10),transforming growth factorβ1(TGF-β1)and vascular endothelial growth factor(VEGF)that suppress the function of immune cells or induce apoptosis of immune cells.Our study also found B16F10 cell culture supernatant(B16F10-CS)suppressed lymphocyte proliferation and perforin and granzyme B production in lymphocytes after induction with phytohemagglutinin(PHA),as well as lymphocyte proliferation in the mixed lymphocyte reaction.The suppression also associated with elevated levels of immunosuppressive IL-10,TGF-β1 and VEGF in B16F10-CS.Further,the production of IL-10,TGF-β1,and VEGF in B16F10 melanoma cells and lung carcinoma LA795 cells was suppressed by G.polysaccharides at both mRNA and protein levels.On the contrary,the production of IL-2,IFN-γand TNF-αin mononuclear lymphocytes was suppressed by B16F10-CF at both the mRNA and protein levels,whereas the suppression was ameliorated by G.polysaccharides.B16F10-CS was suppressive to the viability,phagocytic activity,NO production,TNF-αproduction and activity in peritoneal macrophages while G.polysaccharides had the antagonistic effects against this suppression.Then subsequently,the plasma of patients with lung cancer suppressed proliferation,CD69 expression,and perforin and granzyme B production in lymphocytes upon activation by PHA.However,these suppressive effects were reversed by G.polysaccharides.In conclusion,G.polysaccharides can improve the nature of B16F10 cells to activate lymphocytes and antagonize immunosuppression induced by B16F10-CS in lymphocytes and macrophages.These findings indicate that G.polysaccharides can restraint tumor evasion from immune surveillance,suggesting this potential value of G.polysaccharide to facilitate cancer immunotherapy.
