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981.
Combinations of problem structuring methods with hard OR methodologies are seldom described in the literature. This paper will reflect on the barriers to such combinations that can be seen at the philosophical level—paradigm incommensurability—and cognitive level—type of personality and difficulty of switching paradigm. This paper examines the combination of Soft Systems Methodology and Discrete Event Simulation within an Intermediate Care case study. The paper will argue, by way of the practical application, that these problems are not insurmountable and that the result can be seen as interplay of the soft and hard paradigms. The idea of yin and yang is proposed as a metaphor for this process. 相似文献
982.
N Murakami T Tanase S Nagai Y Sato T Ueda J Sakakibara H Ando Y Hotta K Takeya 《Chemical & pharmaceutical bulletin》1991,39(8):1962-1966
The Diels-Alder reactions of a cardiac glycoside, proscillaridin (1), with some dienophiles were investigated. The reaction of 1 with alkenes such as methyl vinyl ketone and methyl acrylate afforded 3-oxo-2-oxabicyclo[2.2.2]oct-7-enes (2-5) and para-substituted benzene derivatives (6 and 7), while 1 reacted with alkynes (3-butyn-2-one, methyl propiolate) to yield para- or meta-substituted benzene derivatives (6-9). The biological activities of the resulting derivatives were evaluated by the use of isolated guinea-pig papillary muscle preparations and Na+,K(+)-adenosine triphosphatase (ATPase) preparation from dog kidney. Among the proscillaridin derivatives, compounds 4 and 7 moderately inhibited Na+,K(+)-ATPase activity. Furthermore, the concentration range of 7 over which its positive inotropic effect on guinea-pig papillary muscle preparations, increased from 5% to 95% of maximum was broader than that of 1, i.e., concentration dependency was maintained over a greater range of concentration. 相似文献
983.
A Haag-Ruelle Scattering Theory for Euclidean Lattice Field Theories is developed.Work supported by DAAD, Deutscher Akademischer Austauschdienst. Partially supported by CNPq 相似文献
984.
Gulis I. M. Komyak A. I. Saechnikov K. A. Tsvirko V. A. 《Journal of Applied Spectroscopy》1989,50(3):257-262
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 50, No. 3, pp. 385–391, March, 1989. 相似文献
985.
Summary The influence of internal degrees of freedom on the behaviour of one-dimensional systems is discussed. For systems with half-filled
bands the coupling to internalviz. lattice coordinates decides whether Peierls distortion is caused by intramonomer coordinates or by a lattice coordinate.
Thereby the various intramonomer degrees of freedom act cooperatively. We show that there is a small regime of parameters
where both kinds of distortion exist simultaneously. For increasing temperature we find that distortions can also move from
the lattice coordinate to the intramonomer coordinate. 相似文献
986.
High-average-power and high-energy lasers with good beam quality are fundamental tools for pumping high-peak and high-average-power ultrafast Ti:sapphire laser systems. Laser-diode (LD) pumped solid slate lasers with phase conjugation offer a unique combination of efficiency, reliability, and compactness. We present the design details and performance characteristics of a 360-W 1-kHz LD pumped Nd:YAG phase-conjugated laser. We also discuss the basic design aspects and present our preliminary experimental investigations on ultrashort-pulse laser systems. 相似文献
987.
988.
989.
Y Watanabe M Suda Y Matsumoto K Takayama M Matsumoto W Zhao 《Chemical & pharmaceutical bulletin》1991,39(9):2391-2394
The dissolution behavior of the aspirin enteric granule prepared using acylglycerols, glyceryl monostearate (GMS) and glyceryl trilaurate (GTL), was investigated in vitro and in human subjects in a fasting or non-fasting state. Aspirin was slowly released from the granule in vitro at pH 1.2. No acceleration of the aspirin dissolution rate in the medium without lipase and cholic acid was observed when the pH level of the medium increased to a neutral region (pH 6.4). However, the dissolution of aspirin was significantly increased by increasing the concentrations of lipase and cholic acid in the medium. Lipase appears to play an essential role in the dissolution process of aspirin granules. In human subjects, the average levels of the cumulative amount of total salicylate excreted in a urine-time curve, and the mean residence time (MRT) obtained after oral administration of a granule in the fasting state were markedly delayed in comparison with the results observed using an aqueous solution and a crystalline form of aspirin. In comparing the fasting condition with the non-fasting condition (after food ingestion), no significant difference was recognized in the total amount of salicylate excreted in urine to an infinite time (Ae(infinity)), whether the MRT was obtained by granule, crystalline form or aqueous solution. It can be concluded that aspirin granule prepared by GMS and GTL has a property of pancreatic lipase-sensitive dissolution, and its bioavailability is unaffected by food intake. 相似文献
990.
We found a strong paraoxon-hydrolyzing activity (23.4 +/- 8.50 nmol/h/individual and 137 +/- 86.2 nmol/h/mg protein) in the crude extract from larvae of Culex tritaeniorhynchus Toyama 89, which is markedly resistant to organophosphorous insecticides. The activity was higher than those from Cx. tritaeniorhynchus re-e-ae (0.175 +/- 0.0336 and 1.83 +/- 0.651), Anopheles omorii (0.112 +/- 0.0301 and 1.86 +/- 0.746) and An. stephensi (0.0651 +/- 0.0713 and 0.789 +/- 0.910), which are susceptible to organophosphorous insecticides. These facts suggest that the high paraoxon-hydrolyzing activity plays a role in the development of organophosphorous resistance in Cx. tritaeniorhynchus. The enzyme preparation obtained from Toyama 89 showed higher activity in the alkaline pH range and its Km values to paraoxon were 0.67 mM in larvae and 0.50 mM in adults. A calcium ion was strictly required for the hydrolysis of paraoxon. Fenitroxon was also hydrolyzed, in addition to paraoxon. However, it did not degradate parathion and fenitrothion at all. Dichlorvos and phenyl acetate competitively inhibited the enzyme. The phenyl acetate-hydrolyzing activity in the preparation of Toyama 89 was significantly (p less than 0.01) lower than those in susceptible strains, and was irreversibly inhibited by paraoxon. Therefore, the paraoxon-hydrolyzing activity belongs to the class of organophosphate compound hydrolases; it must be thus distinguished from bacterial phosphotriesterase. 相似文献