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Ethnopharmacological relevance Japanese Angelica acutiloba root (Angelica root) is included in several Kampo medicines including Yokukansan (YKS). Angelica root and YKS are used for the treatment of a variety of psychological and neurodegenerative disorders. Development of safe and effective therapeutic agents against cerebrovascular disorders will improve the treatment of patients with dementia. Aim of the study The effect of Angelica root and YKS on ischemia-impaired memory has not yet been fully investigated. The present study investigated whether Angelica root is also involved in memory improving and neuroprotective effect of YKS in a model of cerebrovascular ischemia. Materials and methods Male Wistar rats grouped into sham rats received saline, and other three groups subjected to repeated cerebral ischemia induced by 4-vessel occlusion (4-VO), received a 7-day oral administration of either saline, Angelica root or YKS. Memory was evaluated by eight-arm radial maze task. Acetylcholine release (ACh) in the dorsal hippocampus was investigated by microdialysis-HPLC. Apoptosis was determined by terminal deoxynucleotidyl transferase (TdT)-mediated fluorescein-deoxyuridine triphosphate (dUTP) nick-end labeling. Results Ischemia induced apoptosis, reduced release of ACh, and impaired the memory (increased error choices and decreased correct choices). Angelica root and YKS improved the memory deficits, upregulated the release of ACh and prevented 4-VO-induced hippocampal apoptosis. Conclusion The dual ACh-increasing and neuroprotective effect of Angelica root could make it a promising therapeutic agent useful for the treatment of symptoms of cerebrovascular dementia. Angelica root could be one of the components contributing to the memory-improving and neuroprotective effects of YKS. [ABSTRACT FROM AUTHOR]

Phase change and heat transfer in a polystyrene packed bed during melting were experimentally and numerically investigated. When the polystyrene particles were melted, the calculated porosity decreased at the bottom and side walls and increased at the top wall. The tendency of the calculation agreed qualitatively with the observation of the visualized packed bed. However, the interfacial position between the gas layer and the packed bed near the central axis could not be reproduced by the calculation. This may be accounted for by the following two reasons. Firstly, it is not considered in the calculation that the particles above the interfacial position between the gas layer and the packed bed tend to move over the interfacial level due to the buoyancy of the gas in the not-melted packed bed. Secondly, in the experiments, some of the exhausted gas at the melting positions may move not only upward but also to the central region in the packed bed. For the heating rate of a drying oven at T ̇ d = 50 K/h, the measured temperatures at all six positions increased linearly over time and agreed well with the calculated temperatures for all positions. On the other hand, the measured temperatures could not be reproduced by the calculated temperatures except for at the points near the bottom wall at T ̇ d = 500 K/h. Numerical simulation of heat transfer with natural convection in the packed bed before melting was conducted. As the natural convection strongly influenced the heat transfer in the packed bed, the calculated temperature in the packed bed did not agree with the experimental temperature before melting at T ̇ d = 500 K/h. [ABSTRACT FROM AUTHOR]

Abstract: In the distillation process, heat is supplied at a feed heater and a reboiler, and an overhead stream is cooled at a condenser. Almost all of the supplied heat at the reboiler in the conventional distillation process is discarded in the overhead condenser. Conventional energy savings of the distillation processes were fundamentally attained as a result of heat recovery duty in the feed heater being maximized by using the heat of the bottom stream, which enabled the utility (steam or hot oil) rate to the feed heater to be reduced. To achieve further energy saving in the distillation process, “self-heat recuperation technology” (SHRT) was adopted. In this technology, two compressors are installed in the overhead vapor line, which consists of the reflux and the overhead product streams. A compressor (compressor-1) treats the reflux stream and the other compressor (compressor-2) treats the overhead stream. The reboiler duty is supplied by the recuperated heat of the discharged stream from compressor-1 and the feed heater duty is supplied by that from compressor-2, by adiabatic compressions. It could be found that the advanced process with SHRT was able to reduce the energy consumption significantly by using the recuperated heat of the overhead vapor. [Copyright &y& Elsevier]