Aiming at the hybrid flow-shop （HFS） scheduling that is a complex NP-hard combinatorial problem with wide engineering background, an effective algorithm based on differential evolution （DE） is proposed. By using a...Aiming at the hybrid flow-shop （HFS） scheduling that is a complex NP-hard combinatorial problem with wide engineering background, an effective algorithm based on differential evolution （DE） is proposed. By using a special encoding scheme and combining DE based evolutionary search and local search, the exploration and exploitation abilities are enhanced and well balanced for solving the HFS problems. Simulation results based on some typical problems and comparisons with some existing genetic algorithms demonstrate the proposed algorithm is effective, efficient and robust for solving the HFS problems.展开更多
Long-term potentiation （LTP） at synapses between primary afferents and spinal dorsal horn neurons induced by noxious electrical stimulation or injury of peripheral nerve is con- sidered to underlie chronic pain [1]....Long-term potentiation （LTP） at synapses between primary afferents and spinal dorsal horn neurons induced by noxious electrical stimulation or injury of peripheral nerve is con- sidered to underlie chronic pain [1]. The mechanisms of the spinal LTP have been intensively investigated, since it was discovered in 1995 [2]. In recent years, spinal application of ATP [3], brain-derived neurotrophic factor （BDNF） [4] and opioid [5] has been shown to induce spinal LTP at C-fiber synapses in the absence of conditioning activation of primary afferents. This is contrary to the general belief that coinci- dent pre- and postsynaptic activity is needed for LTP induction. Recently, Sandkiihler and his co-workers reported in Science that combined activation of microglia and astro- cytes by P2X7 receptor agonist BzATP induces LTP at synapses between afferent C-fibers and spinal lamina I neurons in the absence of presynaptic activation, which is termed gliogenic LTP [6] （Fig. 1C）. To determine the rela- tionship between the gliogenic LTP and high frequency stimulation （HFS）-indueed LTP, they used transverse lum- bar spinal cord slices with long dorsal roots which were separated into halves. Twenty two lamina I neurons that received independent monosynaptic C-fiber inputs from each dorsal root half were recorded. Homosynaptic LTP is recorded in 12 neurons, among them 6 neurons also show heterosynaptic LTP （Fig. 1A）. Interestingly, heterosynaptic LTP is also induced in 5 neurons in which HFS fails to induce homosynaptic LTP （Fig. 1B）.展开更多
基金supported by the National Natural Science Fundation of China (60774082 70871065+2 种基金 60834004)the Program for New Century Excellent Talents in University (NCET-10-0505)the Doctoral Program Foundation of Institutions of Higher Education of China(20100002110014)
文摘Aiming at the hybrid flow-shop （HFS） scheduling that is a complex NP-hard combinatorial problem with wide engineering background, an effective algorithm based on differential evolution （DE） is proposed. By using a special encoding scheme and combining DE based evolutionary search and local search, the exploration and exploitation abilities are enhanced and well balanced for solving the HFS problems. Simulation results based on some typical problems and comparisons with some existing genetic algorithms demonstrate the proposed algorithm is effective, efficient and robust for solving the HFS problems.
文摘Long-term potentiation （LTP） at synapses between primary afferents and spinal dorsal horn neurons induced by noxious electrical stimulation or injury of peripheral nerve is con- sidered to underlie chronic pain [1]. The mechanisms of the spinal LTP have been intensively investigated, since it was discovered in 1995 [2]. In recent years, spinal application of ATP [3], brain-derived neurotrophic factor （BDNF） [4] and opioid [5] has been shown to induce spinal LTP at C-fiber synapses in the absence of conditioning activation of primary afferents. This is contrary to the general belief that coinci- dent pre- and postsynaptic activity is needed for LTP induction. Recently, Sandkiihler and his co-workers reported in Science that combined activation of microglia and astro- cytes by P2X7 receptor agonist BzATP induces LTP at synapses between afferent C-fibers and spinal lamina I neurons in the absence of presynaptic activation, which is termed gliogenic LTP [6] （Fig. 1C）. To determine the rela- tionship between the gliogenic LTP and high frequency stimulation （HFS）-indueed LTP, they used transverse lum- bar spinal cord slices with long dorsal roots which were separated into halves. Twenty two lamina I neurons that received independent monosynaptic C-fiber inputs from each dorsal root half were recorded. Homosynaptic LTP is recorded in 12 neurons, among them 6 neurons also show heterosynaptic LTP （Fig. 1A）. Interestingly, heterosynaptic LTP is also induced in 5 neurons in which HFS fails to induce homosynaptic LTP （Fig. 1B）.
