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41.
Michael D. Cohen 《Asian Security》2020,16(3):323-342
ABSTRACT What causes variation in the foreign policies of U.S. allies regarding their desired U.S. military role in their region and their troop commitments to U.S. military interventions? This paper addresses this question through documenting and explaining the sources of variation in Australia’s foreign policies regarding these issues over four decades. Treating the two major political parties in Australia and their respective leaders who self-select into them as endogenous, the paper argues that Australian foreign policy, whilst always supportive of the U.S. alliance, has systematically varied. This variation has correlated with the political party in power while the late Cold War and post-Cold War balances of power remained constant. While the Labor party has only been willing to send combat troops to large U.S. military interventions when the latter have a supporting United Nations Security Council Resolution, the conservative Liberal party has been willing to military intervene without this multilateral support. The Labor party, unlike the Liberal party, has also frequently proposed the formation and consolidation of multilateral regional institutions. These preferences render the U.S. to have been necessary for the Labor Party but sufficient for the Liberal party. Future Sino-U.S. armed conflict would provide a harder test of these hypotheses. 相似文献
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Reliable, sensitive, rapid and quantitative enzyme-based assay for gamma-hydroxybutyric acid (GHB) 总被引:1,自引:0,他引:1
Several assays for gamma-hydroxybutyrate (4-hydroxybutyrate, GHB) have been developed based on the enzyme gamma-hydroxybutyrate dehydrogenase (GHB-DH). Enzymatic oxidation of GHB by NAD+ is coupled to diaphorase-mediated reduction of pro-dye to yield colored product. GHB-DH from Ralstonia eutropha was cloned and expressed as a stable fusion protein easily purified by affinity chromatography. Quantitative initial velocity and endpoint versions of the assay in solution are described. Michaelis-Menten parameters for oxidation of GHB and ethanol were estimated. A semi-quantitative "dipstick" version of the assay on paper also is described. Both solution endpoint and "dipstick" assays are sensitive to about 0.05 mg GHB/mL using 10 microL of sample. Ethanol at concentrations possible in urine and agents used to stabilize physiological fluids for forensics analysis do not interfere significantly. The "dipstick" assay also allows detection of GHB in alcoholic beverages after evaporation of about one-fourth drop of beverage before testing. The enzymatic assay for GHB is reliable, sensitive, inexpensive and rapid. 相似文献
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Genipin, the hydrolytic product of geniposide, which is extracted from gardenia fruit, shows good potential as a fingerprint reagent. It develops latent fingerprints on paper as blue impressions with good contrast and resolution. Even very faint impressions that are barely visible in ambient light will fluoresce brightly upon illumination at ca. 590 nm and are best viewed with a barrier filter above 630 nm. Potential advantages of genipin are the combination of colorimetric and fluorogenic activity in one reagent as well as its being a safe and environmentally friendly natural product. 相似文献
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