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21.
22.
Ki Mun Jung Lyn C Thomas Mee Chi So 《The Journal of the Operational Research Society》2015,66(10):1656-1668
Data-based scorecards, such as those used in credit scoring, age with time and need to be rebuilt or readjusted. Unlike the huge literature on modelling the replacement and maintenance of equipment there have been hardly any models that deal with this problem for scorecards. This paper identifies an effective way of describing the predictive ability of the scorecard and from this describes a simple model for how its predictive ability will develop. Using a dynamic programming approach one is then able to find when it is optimal to rebuild and when to readjust a scorecard. Failing to readjust or rebuild a scorecard when they aged was one of the defects in credit scoring identified in the investigations into the sub-prime mortgage crisis. 相似文献
23.
Da Jung Kim Sang-deok Mun Sungwoo YoonChang Hwa Oh Hyoung-Ryun ParkTae-Soo You Junseong Lee Youngjo Kim 《Polyhedron》2011,30(6):1076-1079
Three monomeric boratranes B[(OCH2CH2)nN(CH2CMe2O)3−n] (n = 0, 1; n = 1, 2; n = 2, 3) have been synthesized by the reaction of B(OMe)3 with a series of triethanolateamines such as [(OCH2CH2)nN(CH2CMe2O)3−n]3− (n = 0, L1; n = 1, L2; n = 2, L3), where the number of CMe2 groups adjacent to the OH functionality varied from 3 (L1H3) to 2 (L2H3) to 1 (L3H3). These boratranes 1-3 have been characterized by solution 1H, 13C{1H} and 11B NMR, and the crystal structures of 1 and 2 have been determined by single crystal X-ray diffraction. 相似文献
24.
Jung Hee MoonSo Han Kim Kang Mun LeeTae-Soo You Youngkyu DoYoungjo Kim 《Polyhedron》2011,30(13):2333-2338
Three monomeric germatranes, 1-isopropoxy-3,3,7,7,10,10-hexamethyl-2,8,9-trioxa-5-aza-1-germatricyclo[3.3.3.01,5]undecane (1), 1-isopropoxy-3,3,7,7-tetramethyl-2,8,9-trioxa-5-aza-1-germatricyclo[3.3.3.01,5]undecane (2), and 1-isopropoxy-3,3-dimethyl-2,8,9-trioxa-5-aza-1-germatricyclo[3.3.3.01,5]undecane (3) have been synthesized by the reaction of Ge(O-i-Pr)4 in refluxing toluene with corresponding triethanolamines, (HOCH2CH2)nN(CH2CMe2OH)3−n (n = 0, L1H3; n = 1, L2H3; n = 2, L3H3), where the number of CMe2 groups adjacent to a OH functionality varied from 3 (L1H3) to 2 (L2H3), and to 1 (L3H3). These germatranes 1-3 have been characterized by solution 1H and 13C{1H} NMR and the solid state structure of 2 has been determined by single crystal X-ray diffraction. 相似文献
25.
26.
Choi JH Park JG Jeon HJ Kim MS Lee MR Lee MN Sonn S Kim JH Lee MH Choi MS Park YB Kwon OS Jeong TS Lee WS Shim HB Shin DH Oh GT 《Experimental & molecular medicine》2011,43(8):471-478
A variety of benzylidenethiazole analogs have been demonstrated to inhibit 5-lipoxygenase (5-LOX). Here we report the anti-atherogenic potential of 5-(4-hydroxy- 2,3,5-trimethylbenzylidene) thiazolidin-2,4-dione (HMB-TZD), a benzylidenethiazole analog, and its potential mechanism of action in LDL receptor-deficient (Ldlr-/-) mice. HMB-TZD Treatment reduced leukotriene B4 (LTB4) production significantly in RAW264.7 macrophages and SVEC4-10 endothelial cells. Macrophages or endothelial cells pre-incubated with HMB-TZD for 2 h and then stimulated with lipopolysaccharide or tumor necrosis factor-alpha (TNF-α) displayed reduced cytokine production. Also, HMB-TZD reduced cell migration and adhesion in accordance with decreased proinflammatory molecule production in vitro and ex vivo. HMB-TZD treatment of 8-week-old male Ldlr-/- mice resulted in significantly reduced atherosclerotic lesions without a change to plasma lipid profiles. Moreover, aortic expression of pro-atherogenic molecules involved in the recruitment of monocytes to the aortic wall, including TNF-α , MCP-1, and VCAM-1, was downregulated. HMB-TZD also reduced macrophage infiltration into atherosclerotic lesions. In conclusion, HMB-TZD ameliorates atherosclerotic lesion formation possibly by reducing the expression of proinflammatory molecules and monocyte/macrophage recruitment to the lesion. These results suggest that HMB-TZD, and benzylidenethiazole analogs in general, may have therapeutic potential as treatments for atherosclerosis. 相似文献
27.
Murale DP Lee KM Kim K Churchill DG 《Chemical communications (Cambridge, England)》2011,47(46):12512-12514
A novel fluorescent difluoroboroazaoxobenzazulene dye has been synthesized from commercially available substrates in "one pot"; it was characterized structurally and spectroscopically, derivatized and finally compared to a related BODIPY system that demonstrates "turn-on" H(+) (42-fold) and F(-) (~5-fold) responses. 相似文献
28.
Four proteoglycans were sequentially extracted from Hypsizygus marmoreus using 0.1 M NaOH (alkali-soluble proteoglycans [F1] and alkali-insoluble proteoglycans [F3]) and 0.1 M HCl (acid-soluble proteoglycans [F2] and acid-insoluble proteoglycans [F4]), and their structures and immunomodulatory activities were investigated. The proteoglycans were found to contain carbohydrates (19.8-82.4%) with various amounts of proteins (7.7-67.3%), and glucose was the major monosaccharide unit present, along with trace amounts of galactose. The molecular weights (Mw) and the radius of gyration (Rg) of these proteoglycans showed ranges of 16 × 10(4)-19,545 × 10(4) g/mol and 35-148 nm, respectively, showing significant variations in their molecular conformations. The backbones of F1 and F2 were mainly connected through a-(1→3), (1→4) and b-(1→6)-glycosidic linkages with some branches. The F1 and F2 proteoglycans significantly stimulated Raw264.7 cells to release nitric oxide (NO), prostaglandin E2 (PGE(2)) and various cytokines, such as IL-1β, TNF-α and IL-6 by inducing their mRNA expressions. 相似文献
29.
A new method for the identification and colorimetric estimation of Co(II) with 2-carboxy-isonitrosoacetanilide has been developed. This reagent is specific and its sensitiviness is D = 10b-6(1:1,000,000). The best possible conditions are indicated for the colorimetric determination whereby Beer's law holds for dilutions to 1,2:1,000,000. 相似文献
30.
Streed EW Mun J Boyd M Campbell GK Medley P Ketterle W Pritchard DE 《Physical review letters》2006,97(26):260402
Continuous and pulsed quantum Zeno effects were observed using a 87Rb Bose-Einstein condensate. Oscillations between two ground hyperfine states of a magnetically trapped condensate, externally driven at a transition rate omega(R), were suppressed by destructively measuring the population in one of the states with resonant light. The suppression of the transition rate in the two-level system was quantified for pulsed measurements with a time interval deltat between pulses and continuous measurements with a scattering rate gamma. We observe that the continuous measurements exhibit the same suppression in the transition rate as the pulsed measurements when gammadeltat=3.60(0.43), in agreement with the predicted value of 4. Increasing the measurement rate suppressed the transition rate down to 0.005 omega(R). 相似文献