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311.
Piasecki Thomas M.; Niaura Raymond; Shadel William G.; Abrams David; Goldstein Michael; Fiore Michael C.; Baker Timothy B. 《Canadian Metallurgical Quarterly》2000,109(1):74
Considerable research shows that withdrawal severity is inconsistently related to smoking cessation outcomes. This may result from measurement problems or failure to scrutinize important dimensions of the withdrawal experience. Two recent studies demonstrated that withdrawal elevation and variations in the time course of withdrawal were related to relapse in smokers treated with the nicotine patch (T. M. Piasecki, M. C. Fiore, & T. B. Baker, 1998). This article reports a conceptual replication and extension of those findings in unaided quitters. Evidence for temporal heterogeneity was found across different types of withdrawal symptoms. Patterns or slopes of affect and urge reports over time predicted smoking status at follow-up, as did mean elevation in withdrawal symptoms. These results suggest that affect and urge withdrawal symptoms make independent contributions to relapse and that relapse is related to both symptom severity and trajectory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
312.
Bob Zeleznik Loring Holden Michael Capps Howard Abrams & Tim Miller 《Computer Graphics Forum》2000,19(3):91-98
We describe the Scene-Graph-As-Bus technique (SGAB), the first step in a staircase of solutions for sharing software components for virtual environments. The goals of SGAB are to allow, with minimal effort, independently-designed applications to share component functionality; and for multiple users to share applications designed for single users.This paper reports on the SGAB design for transparently conjoining different applications by unifying the state information contained in their scene graphs. SGAB monitors and maps changes in the local scene graph of one application to a neutral scene graph representation (NSG), distributes the NSG changes over the network to remote peer applications, and then maps the NSG changes to the local scene graph of the remote application. The fundamental contribution of SGAB is that both the local and remote applications can be completely unaware of each other; that is, both applications can interoperate without code or binary modification despite each having no knowledge of networking or interoperability. 相似文献
313.
Youth tobacco use has increased substantially in the United States during the past decade. This increase can be attributed, in part, to the potency of cigarette advertising and relative ineffectiveness of antismoking advertising. In this article, the authors argue that an understanding of the effects of these 2 competing forms of advertising on youth smoking is limited in current theoretical treatments and that an integrative theoretical perspective has yet to be advanced. The authors argue that the elaboration likelihood model (R.E. Petty & J.T. Cacioppo, 1986) offers a framework with sufficient explanatory power in this domain. Prevention and legislative interventions may benefit from this analysis, which ultimately may help to decrease youth tobacco use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
314.
315.
The human cerebral cortex is topologically equivalent to a sphere when it is viewed as closed at the brain stem. Due to noise and/or resolution issues, magnetic resonance imaging may see "handles" that need to be eliminated to reflect the true spherical topology. Shattuck and Leahy present an algorithm to correct such an image. The basis for their correction strategy is a conjecture, which they call the spherical homeomorphism conjecture, stating that the boundary between the foreground region and the background region is topologically spherical if certain associated foreground and background multigraphs are both graph-theoretic trees. In this paper, we prove the conjecture, and its converse, under the assumption that the foreground/background boundary is a surface. 相似文献
316.
Modulated (frequency-domain) infrared photothermal radiometry (PTR) is used as a dynamic quantitative dental inspection tool complementary to modulated luminescence (LM) to quantify sound enamel or dentin. A dynamic high-spatial-resolution experimental imaging setup, which can provide simultaneous measurements of laser-induced modulated PTR and LM signals from defects in teeth, has been developed. Following optical absorption of laser photons, the experimental setup can monitor simultaneously and independently the nonradiative (optical-to-thermal) energy conversion by infrared PTR and the radiative deexcitation by LM emission. The relaxation lifetimes (tau1, tau2) and optical absorption, scattering, and spectrally averaged infrared emission coefficients (mu(alpha), mu(s), mu(IR)) of enamel are then determined with realistic three-dimensional LM and photothermal models for turbid media followed by multiparameter fits to the data. A quantitative band of values for healthy enamel with respect to these parameters can be generated so as to provide an explicit criterion for the assessment of healthy enamel and, in a future extension, to facilitate the diagnosis of the onset of demineralization in carious enamel. 相似文献
317.
Rakowski William; Dube Catherine E.; Marcus Bess H.; Prochaska James O.; Velicer Wayne F.; Abrams David B. 《Canadian Metallurgical Quarterly》1992,11(2):111
Investigated motivational and cognitive processes of behavior change with respect to mammography screening. 142 women (aged 40–75 yrs) answered a 41-item questionnaire consisting of statements based on constructs from the transtheoretical model of behavior change. Principal-components analysis identified 2 factors: a 6-item component representing positive perceptions of mammography (pros) and a 6-item component representing avoidance of mammography (cons). Pros, cons, and a derived decisional balance measure (pros minus cons) were associated with stage of mammography adoption. The model is discussed as it relates to other theories of behavior change and as a general strategy for analyzing perceptual data pertinent to health-related actions and intentions for behavioral change. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
318.
Gain and output power of sealed-off waveguide CO2 lasers are presented as a function of gas mixtures and total gas pressure. Experimental data on circular-bore and square-channel waveguide lasers are presented. Output power per unit length of 0.2 W/cm is achieved for both types of lasers in agreement with gas-discharge scaling laws which are presented. Saturation intensities as high as 24 kW/cm2are inferred from the data. The effects of the optical properties of the waveguide wall material on the waveguide losses are discussed and theoretical waveguide loss versus wavelength is presented for BeO, Al2 O3 , and fused silica. 相似文献
319.
Corstjens PL Li S Zuiderwijk M Kardos K Abrams WR Niedbala RS Tanke HJ 《IEE proceedings. Nanobiotechnology》2005,152(2):64-72
The development of up-converting phosphor reporter particles has added a powerful tool to modern detection technologies. Carefully constructed phosphor reporters have core-shell structures with surface functional groups suitable for standard bio-conjugations. These reporters are chemically stable, possess the unique property of infrared up-conversion, and are readily detected. In contrast to conventional fluorescent reporters, up-converting phosphor particles do not bleach and allow permanent excitation with simultaneous signal integration. A large anti-Stokes shift (up to 500 nm) separates discrete emission peaks from the infrared excitation source. Along with the unmatched contrast in biological specimens due to the absence of autofluorescence upon infrared excitation, up-converting phosphor technology (UPT) has unique properties for highly-sensitive particle-based assays. The production and characteristics of UPT reporter particles as well as their application in various bioassays is reviewed. 相似文献
320.
A general method for synthesis of insect pheromones having alkyl branched carbon skeletons is demonstrated with the preparation of a diastereomeric mixture of 8-methyl-2-decanol, whose propionate is an attractant of someDiabrotica species. The procedure involves reaction of a ketone with lithium acetylide ethylenediamine complex to afford a propargylic alcohol containing the branch of the target molecule. Copper (1) mediated alkylation of the derived propargylic acetate with a primary alkyl halide yields a trisubstituted allene having the desired chain length, and isomerization with an alkali metal amide of either ethylenediamine or 1,3-diaminopropane, affords the alkyl branched terminal acetylene. The triple bond is converted to the methyl ketone and reduced to the methyl carbinol. The reactions proceed in good yield, and can be conveniently carried out on large scale. The method should prove useful for production of pheromone components in cases where diastereomeric mixtures can be employed.Issued as NRCC No. 27519. 相似文献