报道了浙江蔷薇科Rosaceae悬钩子属Rubus L.植物分类研究中的若干新发现:(1)描述了1新种--掌叶山莓R.palmatiformisZ.H.Chen,F.ChenetF.G.Zhang;2新变种--圆叶悬钩子R.amphidasysFockevar.suborbiculatus Z. H. Chen, W. Y. Xie et F. G...报道了浙江蔷薇科Rosaceae悬钩子属Rubus L.植物分类研究中的若干新发现:(1)描述了1新种--掌叶山莓R.palmatiformisZ.H.Chen,F.ChenetF.G.Zhang;2新变种--圆叶悬钩子R.amphidasysFockevar.suborbiculatus Z. H. Chen, W. Y. Xie et F. G. Zhang和展毛悬钩子R. hakonensis Franch. et Sav. var. villosulusZ. H.Chen, W. Y. Xie et F. G. Zhang。(2)恢复了箱根悬钩子R. hakonensis Franch. et Sav.的种级地位,纠正了以往的错误鉴定;将三裂中南悬钩子R.grayanusMaxim.var.trilobatusT.T.YuetL.T.Lu和无毛光果悬钩子R.glabricarpus var. glabratus C. Z. Zheng et Y. Y. Fang作为武夷悬钩子R. jiangxiensis Z. X. Yu, W. T. Ji et H. Zheng的新异名。(3)报道了3个植物分布新记录,其中攀枝莓R. flagelliflorus Focke ex Diels.和铅山悬钩子R. tsangii Merr.var.yanshanensis(Z.X.YuetW.T.Ji)L.T.Lu为浙江分布新记录,黄果蓬蘽R.hirsutusThunb.f.xanthocarpus(Nakai) M. Kim为中国分布新记录。展开更多
Neurons in the brain utilize various firing trains to encode the input signals they have received. Firing behavior of one single neuron is thoroughly explained by using a bifurcation diagram from polarized resting to ...Neurons in the brain utilize various firing trains to encode the input signals they have received. Firing behavior of one single neuron is thoroughly explained by using a bifurcation diagram from polarized resting to firing, and then to depolarized resting. This explanation provides an important theoretical principle for understanding neuronal biophysical behaviors. This paper reports the novel experimental and modeling results of the modification of such a bifurcation dia- gram by adjusting small conductance potassium （SK） channel. In experiments, changes in excitability and depolarization block in nucleus accumbens shell and medium-spiny projection neurons are explored by increasing the intensity of injected current and blocking the SK channels by apamin. A shift of bifurcation points is observed. Then, a Hodgkin-Huxley type model including the main electrophysiological processes of such neurons is developed to reproduce the experimental results. The reduction of SK channel conductance also shifts the bifurcations, which is in consistence with experiment. A global bifurcation paradigm of this shift is obtained by adjusting two parameters, intensity of injected current and SK channel con- ductance. This work reveals the dynamics underpinning modulation of neuronal firing behaviors by biologically important ionic conductance. The results indicate that small ionic conductance other than that responsible for spike generation can modify bifurcation points and shift the bifurcation diagram and, thus, change neuronal excitability and adaptation.展开更多
文摘报道了浙江蔷薇科Rosaceae悬钩子属Rubus L.植物分类研究中的若干新发现:(1)描述了1新种--掌叶山莓R.palmatiformisZ.H.Chen,F.ChenetF.G.Zhang;2新变种--圆叶悬钩子R.amphidasysFockevar.suborbiculatus Z. H. Chen, W. Y. Xie et F. G. Zhang和展毛悬钩子R. hakonensis Franch. et Sav. var. villosulusZ. H.Chen, W. Y. Xie et F. G. Zhang。(2)恢复了箱根悬钩子R. hakonensis Franch. et Sav.的种级地位,纠正了以往的错误鉴定;将三裂中南悬钩子R.grayanusMaxim.var.trilobatusT.T.YuetL.T.Lu和无毛光果悬钩子R.glabricarpus var. glabratus C. Z. Zheng et Y. Y. Fang作为武夷悬钩子R. jiangxiensis Z. X. Yu, W. T. Ji et H. Zheng的新异名。(3)报道了3个植物分布新记录,其中攀枝莓R. flagelliflorus Focke ex Diels.和铅山悬钩子R. tsangii Merr.var.yanshanensis(Z.X.YuetW.T.Ji)L.T.Lu为浙江分布新记录,黄果蓬蘽R.hirsutusThunb.f.xanthocarpus(Nakai) M. Kim为中国分布新记录。
基金Project supported by the National Natural Science Foundation of China (Grant No.30900443)the Fundamental Research Funds for the Central Universities,China (Grant Nos.GK201302052 and GK261001007)
文摘Neurons in the brain utilize various firing trains to encode the input signals they have received. Firing behavior of one single neuron is thoroughly explained by using a bifurcation diagram from polarized resting to firing, and then to depolarized resting. This explanation provides an important theoretical principle for understanding neuronal biophysical behaviors. This paper reports the novel experimental and modeling results of the modification of such a bifurcation dia- gram by adjusting small conductance potassium （SK） channel. In experiments, changes in excitability and depolarization block in nucleus accumbens shell and medium-spiny projection neurons are explored by increasing the intensity of injected current and blocking the SK channels by apamin. A shift of bifurcation points is observed. Then, a Hodgkin-Huxley type model including the main electrophysiological processes of such neurons is developed to reproduce the experimental results. The reduction of SK channel conductance also shifts the bifurcations, which is in consistence with experiment. A global bifurcation paradigm of this shift is obtained by adjusting two parameters, intensity of injected current and SK channel con- ductance. This work reveals the dynamics underpinning modulation of neuronal firing behaviors by biologically important ionic conductance. The results indicate that small ionic conductance other than that responsible for spike generation can modify bifurcation points and shift the bifurcation diagram and, thus, change neuronal excitability and adaptation.
