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排序方式: 共有1002条查询结果,搜索用时 31 毫秒
101.
Elder John P.; Ayala Guadalupe X.; Campbell Nadia R.; Slymen Donald; Lopez-Madurga Eva T.; Engelberg Moshe; Baquero Barbara 《Canadian Metallurgical Quarterly》2005,24(1):49
Participants (N = 357) were randomly assigned to 1 of 3 conditions: lay health advisor (promotora) plus tailored print materials, tailored print materials only (tailored), or off-the-shelf print materials (control). The primary outcomes were calories from fat and daily grams of fiber. Secondary outcomes included total energy intake, total and saturated fat intake, and total carbohydrates. Adjusted for baseline values, calories from fat were 29%, 30%, and 30% for the promotora, tailored, and control conditions, respectively, and grams of fiber consumed were 16 g, 17 g, and 16 g. Significant Condition X Time interactions were not observed between baseline and 12-weeks postintervention. The LHA condition achieved significantly lower levels of energy intake, total fat and saturated fat, and total carbohydrates. The relative superiority of the promotora condition may derive from the personal touch achieved in the face-to-face interactions or from the women's use of print materials under the promotora's guidance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Nadia Maïzi 《Systems & Control Letters》1994,22(6):457-465
We present an approach to the problem of finding an L∞ approximant of the infinite-dimensional system describing the diffusion of heat in a wall. We show that this system can be regarded as a delay system with Laplace variable √s. We are able to get results, established in Zwart et al. (1988), about partial fraction expansion for delay systems, achieved by some adjustment to the specificities of our particular case. The determination of an L∞ approximant is realised in two steps, using the optimal Hankel-norm approximation. 相似文献
103.
Efficient self-collision detection on smoothly discretized surface animations using geometrical shape regularity 总被引:6,自引:0,他引:6
We present a new algorithm for detecting self-collisionson highly discretized moving polygonal surfaces. If is based on geometrical shape regularity properties that permit avoiding many useless collision tests. We use an improved hierarchical representation of our surface that, besides the optimizations inherent to hierarchisation, allows us to fake adjacency information to our advantage for applying efficiently our geometrical optimizations. We reduce the computation time between each frame by building automatically the hierarchical structure once as a preprocessing task. We describe the main principles of our algorithm, followed by some performance tests. 相似文献
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G Cristalli R Volpini S Vittori E Camaioni A Monopoli A Conti S Dionisotti C Zocchi E Ongini 《Canadian Metallurgical Quarterly》1994,37(11):1720-1726
A series of new 2-alkynyl and 2-cycloalkynyl derivatives of adenosine-5'-N-ethyluronamide (NECA) and of N-ethyl-1'-deoxy-1'-(6-amino-2-hexynyl-9H-purin-9-yl)-beta-D- ribofuranuronamide (1, HE-NECA), bearing hydroxy, amino, chloro, and cyano groups in the side chain, were synthesized. The compounds were studied in binding and functional assays to assess their potency for the A2 compared to A1 adenosine receptor. The presence of an alpha-hydroxyl group in the alkynyl chain of NECA derivatives accounts for the A2 agonist potency, leading to compounds endowed with sub-nanomolar affinity in binding studies. However, these analogues also possess good A1 receptor affinity resulting in low A2 selectivity. From functional experiments the 4-hydroxy-1-butynyl (6) and the 4-(2-tetrahydro-2H-pyranyloxy)-1-butynyl (16) derivatives appear to be very potent in inducing vasorelaxation without appreciable effect on heart rate. The new compounds were also tested as inhibitors of platelet aggregation induced by ADP. Introduction of an alpha-hydroxyl group in the alkynyl side chain caused a greater increase in antiaggregatory activity than either NECA or HE-NECA, resulting in the most potent inhibitors of platelet aggregation so far known in the nucleoside series. The presence of an alpha-quaternary carbon such as the 3-hydroxy-3,5-dimethyl-1-hexynyl (12) and the 3-hydroxy-3-phenyl-1-butynyl (15) derivatives markedly reduced the antiaggregatory potency without affecting the A2 affinity. The hydrophobicity index (k') of the new nucleosides barely correlated with the binding data, whereas high k' values were associated with increased A2 vs A1 selectivity but with reduced activity in all functional assays. Some of the compounds synthesized possess interesting pharmacological properties. Compounds having an appropriate balance between vasorelaxation and antiplatelet activity, if confirmed in vivo, deserve further development for the treatments of cardiovascular disorders. 相似文献
106.
The paper is concerned with simulating the macroeconomic adjustment processes arising in a small open economy experiencing a temporary period of oil production. In a recent paper, Harvie conducted a similar exercise for an economy in which the spending effect arising from such oil production dominated the resource movement effect. That paper concluded that the wage adjustment processes operative were important in influencing the macroeconomic adjustment process arising. Specifically, that paper concluded that wage indexation was preferable during the period of oil production, but that de-indexation was preferable in the post oil production period. Although, in the present paper, the principles underlying the simulated model are the same as in Harvie, the emphasis here is placed on the resource movement consequences arising from temporary oil production. The major conclusion identified is that wages policy is still important in influencing the macroeconomic adjustment processes identified. However, a difference arises not in regard to the profile of that adjustment but rather in its magnitude. The paper emphasizes, in particular, developments in non-oil output, consumer prices, and the stock of domestically held foreign assets. The simulation results suggest that, where the resource movement effect dominates, it would be preferable to de-index wages during the period of oil production and index wages in the post oil production period. Hence wages policy should be regarded as an important component of a government's policy response arising from a period of temporary oil production, irrespective of whether the resource movement or spending effect dominates. However, what that policy response should be would depend on the relative importance of either effect. 相似文献
107.
108.
The serum tocopherol levels were determined on 923 workers (18–62 years of age) from the textile, chemical and metallurgical industries. Tocopherol levels varied between 0,20 and 1,86 mg per 100 ml serum, the mean value being 0,77 ± 0,01 mg per 100 ml, but in 148 subjects (16%) concentrations under 0,5 mg per 100 ml were found. For women the average was significantly (p < 0,05) lower than that for men (0,75 ± 0,02 compared to 0,79 ± 0,01) and the prevalence of levels below 0,5 mg per 100 ml greater (18,4% compared to 12,6%). Independent of sex the serum tocopherol level increased with age (from 0,59 ± 0,02 under 26 years, to 0,87 ± 0,05 mg per 100 ml for the group over 55 years, p < 0,001). By grouping the persons according to the tocopherol levels (A = up to 0,5 mg per 100 ml; B = 0,51–1,0 and C = over 1,0 mg per 100 ml) and by calculating for each group the average values of the daily fat intake (supplied especially by sunflower oil) a relationship was found between the two series of values, but overall this did not reach statistical significance. 相似文献
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110.