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131.
A new technique for fabrication of channel structures with diameters down to 13 microm in fluorinated ethylene propylene (also known as poly(tetrafluoroethylene-co-hexafluoropropylene), FEP) is described. The technique is based on the unique property of a dual-layer fluoropolymer tubing consisting of an outer layer of poly(tetrafluoroethylene) (PTFE) and an inner layer of FEP. When heated (>350 degrees C), the outer PTFE layer shrinks while the inner FEP layer melts, resulting in filling of all empty space inside the tubing with FEP. The channel structures are formed using tungsten wires as templates that are pulled out after completion of the shrinking and melting process. While several analytical devices have been reproducibly prepared and shown to function, this report describes a single example. A microreactor coupled to an electrochemical flow cell detects the biuret complex of the natively electroinactive peptide des-Tyr-Leu-enkephalin. 相似文献
132.
133.
The authors assert that L. B. Smith and L. Samuelson's (2006; see record 2006-20488-029) most recent critique of A. E. Booth, S. R. Waxman, and Y. T. Huang's (2005; see record 2005-05098-004) work missed its mark, deflecting attention from the important theoretical difference between the two sets of authors' positions and focusing instead on imagined differences and minor expositional complaints. The authors' goal in this response is twofold. First, they aim to redirect attention to the 1 clear difference between the 2 theoretical positions regarding word learning, a difference that is focused on the role of conceptual (in conjunction with perceptual) information in word learning. Second, they place L. B. Smith and L. Samuelson's (2006) current critique in the context of previous exchanges. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
Davies W. Hobart; Satter Ellyn; Berlin Kristoffer S.; Sato Amy F.; Silverman Alan H.; Fischer Elizabeth A.; Arvedson Joan C.; Rudolph Colin D. 《Canadian Metallurgical Quarterly》2006,20(3):409
The feeding of young children is fundamentally a relational and multisystemic process. Successful treatment of clinically significant feeding problems involves careful assessment of the full range of influences on the feeding relationship and integrated treatment approaches. However, current diagnostic approaches to feeding disorders tend to be reductionistic, exclusively focused on the child as an individual, and overly concerned with exclusionary criteria. Criteria are proposed for "Feeding Disorder Between Parent and Child" that address these limitations and embrace the complexity of feeding problems. A multiaxial diagnosis that describes the child (including medical, developmental, and behavioral characteristics); the parent; the parent-child relationship; and the social and nutritional context of feeding will more accurately speak to treatment planning in this population. The proposed diagnostic criteria were developed and refined on the basis of the available literature and many years of treatment experience across the authors of this article. The proposed diagnosis will support the development and evaluation of treatment packages with components specifically targeted to issues of the child, parent, parent-child interaction, and the broader environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
135.
Krishnan-Sarin Suchitra; Duhig Amy M.; McKee Sherry A.; McMahon Thomas J.; Liss Thomas; McFetridge Amanda; Cavallo Dana A. 《Canadian Metallurgical Quarterly》2006,14(3):306
This pilot study evaluated the use of contingency management (CM) procedures in combination with cognitive-behavioral therapy (CBT) for smoking cessation in adolescents. Twenty-eight treatment-seeking adolescent smokers participated in a 1-month, school-based smoking cessation program and were randomly assigned to receive either CM with weekly CBT or CBT alone. In the CM+CBT group, biochemical verification of abstinence was obtained twice daily during the first 2 weeks, followed by daily appointments during the 3rd week and once every other day during the 4th week. Participants were monetarily reinforced for abstinence on an escalating magnitude schedule with a reset contingency. At the end of 1 week and 1 month of treatment, abstinence verified using quantitative urine cotinine levels was higher in participants in the CM+CBT group (1 week: 76.7%; 1 month: 53.0%) when compared with the CBT-alone group (1 week: 7.2%; 4 weeks: 0%). These preliminary results provide a strong initial signal supporting the utility of CM techniques for smoking cessation in adolescents and demonstrate the feasibility of implementing such a program in a school setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
136.
Character of Organic Matter in Soil-Aquifer Treatment Systems 总被引:1,自引:0,他引:1
J?rg E. Drewes David M. Quanrud Gary L. Amy Paul K. Westerhoff 《Canadian Metallurgical Quarterly》2006,132(11):1447-1458
The objective of this study was to investigate the character and fate of bulk organics in reclaimed water used for groundwater recharge via soil-aquifer treatment (SAT). The study design followed a watershed guided approach considering hydraulically corresponding samples of drinking water sources, SAT-applied wastewater effluents, and subsequent post-SAT samples representing a series of different travel times in the subsurface. Water samples were fractionated into hydrophobic acids, transphilic acids, and hydrophilic carbon using a XAD resin-based protocol. Extensive characterization of organic carbon in the different samples was performed using state-of-the-art analytical techniques including excitation–emission matrix fluorescence spectroscopy, size exclusion chromatography, carbon-13 nuclear magnetic resonance spectroscopy (13C-NMR), Fourier transform infrared spectroscopy (FTIR), and elemental analysis. During SAT, transphilic and hydrophilic organic matter were preferentially removed. The results generally demonstrated that naturally derived (NOM) and effluent-derived organic matter after SAT overlap extensively in molecular weight distribution, amount and distribution of hydrophobic and hydrophilic carbon fractions, and chemical characteristics based on elemental analysis and 13C-NMR and FTIR spectroscopy. However, the residual portion of the dissolved organic carbon contained both effluent-derived organic matter and NOM. 相似文献
137.
Smell, think and act: A cognitive robot discriminating odours 总被引:1,自引:0,他引:1
In this paper, we explore the integration of an electronic nose and its odour discrimination functionalities into a multi-sensing robotic system which works over an extended period of time. The robot patrols an office environment, collecting odour samples of objects and performing user requested tasks. By considering an experimental platforms which operates over an extended period of time, a number of issues related to odour discrimination arise such as the drift in the sensor data, online learning of new odours, and the correct association of odour properties related to objects. In addition to an electronic nose our robotic system consists of other sensing modalities (vision and sonar), behaviour-based control and a high level symbolic planner. 相似文献
138.
Experimental inflammatory arthritis (EIA) produced by carrageenan injection provokes a rapid bone remodeling state with cortical and cancellous bone loss. The objective of this study was to determine whether changes in cortical mechanical properties and/or geometry occur in long bones, either near or remote to the site of inflammation. EIA was induced in the right tibio-femoral joint of rabbits over 56 days. The right humerus and right femur from 15 normal and 25 arthritis group animals were excized. Semi-cylindrical specimens of the medial cortical shaft were subjected to non-destructive four-point bending tests. Transverse sections at the four contact sites of the loading jig were photographed and digitized to obtain average cross-sectional area (A) and moment of inertia (I). Moment of inertia and slope of the load/deflection curve permitted calculation of modulus of elasticity (E) for each specimen. Load/time curves were also used to calculate per cent stress remaining in relaxation experiments. Per cent stress remaining, E, A, I and
\sqrt {{\text{I/A}}} (radius of gyration) were examined for differences by bone (humerus, femur) and by treatment (N,A) using two way ANOVA. The induction of inflammatory arthritis did not significantly alter the modulus of elasticity in either the femur or humerus; however, arthritis reduced the moment of inertia from
. This was observed in the femur (near the arthritic joint), but not in the humerus (remote from arthritic joint). Analysis of area and ratio I/A demonstrated that this geometric effect of treatment was due to reduced area without gross cross-sectional shape changes. Per cent stress remaining in the femur (but not in the humerus) was higher in the arthritis specimens than in the normal specimens
. Thus, in this arthritis model, the principal mechanical or geometric effect on cortical bone was reduction of the cross-sectional area and moment of inertia. The viscoelastic relaxation response of bone was also altered, perhaps due to loss of water or collagen degradation. 相似文献
139.
Bowers Bonnie B.; Bledsoe Amy E.; Burghardt Gordon M. 《Canadian Metallurgical Quarterly》1993,107(1):25
Several models suggest that animals perform a stable sequence of responses during increasing threat from a potential predator. To test the comparative utility of such models, 45 garter and ribbon snakes from 4 species were given an antipredator behavior test in which the snakes were exposed to a series of 5 levels of escalating threat: (1) threat is out of view, (2) threat looms over arena, (3) threat is nonmoving human hand near snake's head, (4) threat is moving human hand, and (5) threat is experimenter's tapping the snake's body. Five different antipredator behaviors were measured. It was found that both qualitative and quantitative changes in behavior occurred between threat levels. However, species differences were also found in the occurrence and amount of every behavior recorded, which indicates that even closely related species may differ in behaviors exhibited in different phases of a predatory encounter. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
140.
Analyzed stylistic complexity and verb usage in the text of the film Responsible Assertion, an assertiveness training film, using the Computer-Assisted Language Analysis System. Findings suggest that the assertive language in the film was characterized by a wordy, complex style full of many embedded clauses and that assertive speech consisted of monologues containing qualifying phrases. Results suggest that assertiveness trainers should emphasize wordiness and persistence rather than simple sentences. Data indicate that an emphasis on feelings was not crucial in behavior that was judged assertive. Implications for understanding the process and outcome of therapy are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献