AIM: To investigate the acupuncture-modulated gastric motility and its underlying neural mechanism.METHODS: Intragastric pressure and/or waves of gastric contraction in rats were recorded by intrapyloric balloon and c...AIM: To investigate the acupuncture-modulated gastric motility and its underlying neural mechanism.METHODS: Intragastric pressure and/or waves of gastric contraction in rats were recorded by intrapyloric balloon and changes of gastric motility induced by acupuncture stimulation were compared with the background activity before any stimulation. Gastro-vagal or splanchnic-sympathetic nerves were recorded or cut respectively for investigating the involvement of autonomic nerve pathways. Spinalization experiment was also performed.RESULTS: Acupuncture-stimulation by exciting Aδ and/or C afferent fibers, could only modulate gastric motility. Acupuncture-stimulation on fore- and hind-limbs evoked a moderate gastric motility followed by increased vagus discharges with unchanged sympathetic activity, while the same stimulus to the acupoints in abdomen resulted in reversed effects on gastric motility and autonomic nervous activities. The inhibitory gastric response was completely abolished by splanchnic denervation, but the facilitative gastric response to stimulation of acupoints in limbs was not influenced, which was opposite to the effect when vagotomy was performed. The similar depressive effects were produced by the stimulation at the acupoints homo-segmental to the gastric innervation in the animals with or without spinalization. However, the facilitation induced by the stimulation at the acupoints hetero-segmental to the gastric innervation was not observed in the spinalized animals.CONCLUSION: Facilitative effects of stimulating hetero-segmental acupoints are involved in the intact preparation of vagal nerves and spinal cord, while the inhibitory response induced by stimulating homo-segmental acupoints is involved in the intact preparation of sympathetic nerves. Only the acupuncture-stimulation with intensity over the threshold of Aδ and/or C afferent fibers can markedly modulate gastrointestinal motility.展开更多
A resource-based economy is an economic system driven by the exploitation of mineral resources and dominated by the energy, mineral and other resource sectors. In resource- rich areas, there is often an investment bia...A resource-based economy is an economic system driven by the exploitation of mineral resources and dominated by the energy, mineral and other resource sectors. In resource- rich areas, there is often an investment bias toward the resource sector because of the existence of a threshold for investment in human capital in the manufacturing sector. Once the resource sector is dominant, it has a particular atwaction effect on the economic factors; its expansion and spread have a viscosity effect on industry families;, and the sunk costs and path dependence that emerge as industrialization evolves have a lock-in effect on the role of resources. This may give rise to development path dependence and the trap of resource advantage, resulting in a self-strengthening mechanism in resource-based economies. The key to escaping this trap is to break down the resource sector＇s original self-perpetuating mechanism and path dependence, introduce learning and innovation, adjust mechanisms far the distribution of resource benefits and realize industry coordination and transformational economic development.展开更多
We investigate a spin-to-charge conversion mechanism which maps the spin singlet and triplet states to two charge states differing by one electron mediated by an intermediate metastable charge state. This mechanism al...We investigate a spin-to-charge conversion mechanism which maps the spin singlet and triplet states to two charge states differing by one electron mediated by an intermediate metastable charge state. This mechanism allows us to observe fringes in the spin-unblocked region beyond the triplet transition line in the measurement of the exchange oscillations between singlet and triplet states in a four-electron dou- ble quantum dot. Moreover, these fringes are amplified and π-phase shifted, compared with those in the spin blockade region. Unlike the signal enhancement mechanism reported before which produces similar effects, this mechanism only requires one dot coupling to the lead, which is a commonly encountered case especially in imperfect devices. Besides, the crucial tunnel rate asymmetry is provided by the dependence on spin state, not by the asymmetric couplings to the leads. We also design a scheme to control the amplification process, which enables us to extract the relevant time parameters. This mechanism will have potential applications in future investigations of spin qubits.展开更多
基金supported by a grant from the National Social Sciences Fund project "Exploitation of Coal Resources and Regional Economic Development" (Approval Number:08BJL052)a grant from the Program for Supporting Outstanding Young Academic Leaders in Shanxi Higher Education Institutions
基金Supported by National Natural Science Foundation of China, No. C30100245 National Basic Research 973 Program, No. 2005CB523308
文摘AIM: To investigate the acupuncture-modulated gastric motility and its underlying neural mechanism.METHODS: Intragastric pressure and/or waves of gastric contraction in rats were recorded by intrapyloric balloon and changes of gastric motility induced by acupuncture stimulation were compared with the background activity before any stimulation. Gastro-vagal or splanchnic-sympathetic nerves were recorded or cut respectively for investigating the involvement of autonomic nerve pathways. Spinalization experiment was also performed.RESULTS: Acupuncture-stimulation by exciting Aδ and/or C afferent fibers, could only modulate gastric motility. Acupuncture-stimulation on fore- and hind-limbs evoked a moderate gastric motility followed by increased vagus discharges with unchanged sympathetic activity, while the same stimulus to the acupoints in abdomen resulted in reversed effects on gastric motility and autonomic nervous activities. The inhibitory gastric response was completely abolished by splanchnic denervation, but the facilitative gastric response to stimulation of acupoints in limbs was not influenced, which was opposite to the effect when vagotomy was performed. The similar depressive effects were produced by the stimulation at the acupoints homo-segmental to the gastric innervation in the animals with or without spinalization. However, the facilitation induced by the stimulation at the acupoints hetero-segmental to the gastric innervation was not observed in the spinalized animals.CONCLUSION: Facilitative effects of stimulating hetero-segmental acupoints are involved in the intact preparation of vagal nerves and spinal cord, while the inhibitory response induced by stimulating homo-segmental acupoints is involved in the intact preparation of sympathetic nerves. Only the acupuncture-stimulation with intensity over the threshold of Aδ and/or C afferent fibers can markedly modulate gastrointestinal motility.
文摘A resource-based economy is an economic system driven by the exploitation of mineral resources and dominated by the energy, mineral and other resource sectors. In resource- rich areas, there is often an investment bias toward the resource sector because of the existence of a threshold for investment in human capital in the manufacturing sector. Once the resource sector is dominant, it has a particular atwaction effect on the economic factors; its expansion and spread have a viscosity effect on industry families;, and the sunk costs and path dependence that emerge as industrialization evolves have a lock-in effect on the role of resources. This may give rise to development path dependence and the trap of resource advantage, resulting in a self-strengthening mechanism in resource-based economies. The key to escaping this trap is to break down the resource sector＇s original self-perpetuating mechanism and path dependence, introduce learning and innovation, adjust mechanisms far the distribution of resource benefits and realize industry coordination and transformational economic development.
基金supported by the National Key Research and Development Program (2016YFA0301700)the National Natural Science Foundation of China (11674300, 11304301, 11575172,61674132, and 91421303)+2 种基金the Strategic Priority Research Program of Chinese Academy of Sciences (XDB01030000)the Fundamental Research Fund for the Central UniversitiesThis work was partially carried out at the USTC Center for Micro and Nanoscale Research and Fabrication
文摘We investigate a spin-to-charge conversion mechanism which maps the spin singlet and triplet states to two charge states differing by one electron mediated by an intermediate metastable charge state. This mechanism allows us to observe fringes in the spin-unblocked region beyond the triplet transition line in the measurement of the exchange oscillations between singlet and triplet states in a four-electron dou- ble quantum dot. Moreover, these fringes are amplified and π-phase shifted, compared with those in the spin blockade region. Unlike the signal enhancement mechanism reported before which produces similar effects, this mechanism only requires one dot coupling to the lead, which is a commonly encountered case especially in imperfect devices. Besides, the crucial tunnel rate asymmetry is provided by the dependence on spin state, not by the asymmetric couplings to the leads. We also design a scheme to control the amplification process, which enables us to extract the relevant time parameters. This mechanism will have potential applications in future investigations of spin qubits.
