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81.
Borrelli Belinda; McQuaid Elizabeth L.; Novak Scott P.; Hammond S. Katharine; Becker Bruce 《Canadian Metallurgical Quarterly》2010,78(1):34
Objective: Secondhand smoke exposure is associated with asthma onset and exacerbation. Latino children have higher rates of asthma morbidity than other groups. The current study compared the effectiveness of a newly developed smoking cessation treatment with existing clinical guidelines for smoking cessation. Method: Latino caregivers who smoked (N = 133; 72.9% female; mean age = 36.8 years) and had a child with asthma were randomly assigned to receive 1 of 2 smoking cessation counseling interventions during a home-based asthma program: (a) behavioral action model (BAM; modeled on clinical guidelines for smoking cessation) or (b) precaution adoption model (PAM; feedback on the caregiver’s carbon monoxide level and child’s secondhand smoke exposure using Motivational Interviewing). Counseling was delivered by a bilingual Latina health educator, and the content was tailored to Latino values and culture. It was not necessary for smokers to want to quit smoking to participate. Smoking cessation was biochemically verified and secondhand smoke exposure was objectively measured through passive nicotine monitors. Results: Intent-to-treat analyses showed that 20.5% of participants in the PAM condition and 9.1% of those in the BAM condition were continuously abstinent at 2 months posttreatment (OR = 2.54; 95% CI = 0.91–7.10), whereas 19.1% of participants in the PAM condition and 12.3% of those in BAM condition were continuously abstinent at 3 months posttreatment (OR = 1.68; 95% CI = 0.64–4.37). Secondhand smoke exposure decreased only in the BAM condition (p p 相似文献
82.
F. Jack Triepke C. Kenneth Brewer Stephen J. Novak 《Remote sensing of environment》2008,112(3):1037-1050
The study and management of biological communities depends on systems of classification and mapping for the organization and communication of resource information. Recent advances in remote sensing technology may enable the mapping of forest plant associations using image classification techniques. But few areas outside Europe have alliances and associations described in detail sufficient to support remote sensing-based modeling. Northwestern Montana has one of the few completed plant association classifications in the United States compliant with the recently established National Vegetation Classification system. This project examined the feasibility of mapping forest plant associations using Landsat Enhanced Thematic Mapper Plus data and advanced remote sensing technology and image classification techniques.Suitable reference data were selected from an extensive regional database of plot records. Fifteen percent of the plot samples were reserved for validation of map products, the remainder of plots designated as training data for map modeling. Key differentiae for image classification were identified from a suite of spectral and biophysical variables. Fuzzy rules were formulated for partitioning physiognomic classes in the upper levels of our image classification hierarchy. Nearest neighbor classifiers were developed for classification of lower levels (alliances and associations), where spectral and biophysical contrasts are less distinct.Maps were produced to reflect nine forest alliances and 24 associations across the study area. Error matrices were constructed for each map based on stratified random selections of map validation samples. Accuracy for the alliance map was estimated at 60%. Association classifiers provide between 54 and 86% accuracy within their respective alliances. Alternative techniques are proposed for aggregating classes and enhancing decision tree classifiers to model alliances and associations for interior forest types. 相似文献
83.
AM Drewes KD Nielsen L Arendt-Nielsen L Birket-Smith LM Hansen 《Canadian Metallurgical Quarterly》1997,20(8):632-640
The interaction between sleep and pain has been insufficiently studied, and no experiments have investigated whether pathologic sleep patterns as seen in pain patients can be replicated experimentally by well-defined pain stimuli. An experimental model would therefore be valuable for further studies on the interaction between pain and sleep. In this study, three well-defined experimental stimuli (muscle, joint, and cutaneous pain) were applied during sleep, and the electroencephalogram (EEG) pattern was quantified. The pain stimuli were applied during slow-wave sleep in 10 healthy subjects. Using nine surface recordings, the EEG was sampled before and during pain stimuli. Frequency analysis was performed, resulting in 10 EEG features describing the responses to pain. During the muscle-pain stimulus an arousal effect was observed and a decrease in delta (0.5-3.5 Hz) and sigma (12-14 Hz) as well as increases in alpha 1 (8-10 Hz) and beta (14.5-25 Hz) activities were seen. During joint pain, however, more universal EEG changes were seen with a decrease in the lowest frequency bands [delta, theta (3.5-8 Hz) and alpha 1] and an increase in the higher frequencies [alpha 2 (10-12 Hz), sigma and beta bands]. No background EEG changes were observed during the cutaneous stimulus. There were several differences in the responses from the nine EEG channels, but no derivation seemed especially sensitive to detect the evoked changes. The study highlights the complexity of pain on the sleep EEG. The experimental model has shown that pain from different body structures, as well as signals from various EEG derivations, may give different responses in sleep microstructure. 相似文献
84.
KD Travers 《Canadian Metallurgical Quarterly》1997,24(3):344-356
PURPOSE: To analyze the indocyanine green angiographic findings of drusen in the early stages of age-related macular degeneration. METHODS: Sixty-nine eyes of 53 consecutive patients with drusen but without exudative complications of age-related macular degeneration were studied. Drusen were classified into four groups: hard drusen, drusen derived from clusters of hard drusen (hard cluster-derived drusen and soft cluster-derived drusen), membranous drusen, and regressing drusen. An additional category was constituted by reticular pseudodrusen that could be associated with drusen of either the inner or outer macula. Results of contact lens biomicroscopy and fluorescein angiography were compared with findings on indocyanine green angiography. RESULTS: Hard drusen, either isolated hard drusen or hard cluster-derived drusen, were hyperfluorescent during indocyanine green angiography; in contrast, all sizes of soft drusen derived from clusters of hard drusen were hypofluorescent throughout the angiogram. Membranous drusen, visible on biomicroscopy and fluorescein angiography, were not visible during indocyanine green angiography. Regressing drusen may have showed hyperfluorescence at the early stages of indocyanine green angiography, but associated calcium and pigmentation were hypofluorescent. Reticular pseudodrusen were visible on red-free photographs; on midphase and late-phase indocyanine green angiography using the scanning laser ophthalmoscope only, reticular pseudodrusen were seen as a pattern of hypofluorescent dots. CONCLUSION: The indocyanine green angiographic findings add to and support the clinicopathologic classification of drusen. Indocyanine green angiography may help to distinguish the different types of drusen and may thus be of use in evaluating the risk of progressive age-related macular degeneration in patients with drusen. 相似文献
85.
86.
The analytical benefits of using a step-gradient in capillary electrochromatography (CEC) are demonstrated. The application of step-gradient CEC to the analysis of six diuretics of widely differing lipophilicities was evaluated and shown to result in a marked reduction in the analysis time and an improvement in the peak shape for later-eluting lipophilic components. When the step-gradient approach was performed in an automated mode, the retention time RSD for repeated injections was below 1%. 相似文献
87.
88.
Purification of molecularly bridged metal nanoparticle arrays by centrifugation and size exclusion chromatography. 总被引:3,自引:0,他引:3
Size exclusion chromatography and centrifugation separation protocols were developed and compared for isolating enriched fractions of phenylethynyl-bridged metal nanoparticle dimers and trimers from the monomeric particle starting material. Both methods enabled the isolation of enriched fractions of a desired array without causing significant sample aggregation or replacement of the phenylethynyl bridge. Solutions containing ca. 70% bridged gold dimers were obtained using either method. The further development of methods for separating discrete arrays of covalently bridged nanoparticle homo and hetero structures is expected to help advance our understanding of collective metal particle electronic structure-function relationships. 相似文献
89.
In this paper, the development of natural draft cooling towers diagnostics is presented. Diagnostic method is based on measurements of velocity and temperature fields of the airflow in the entire surface area of cooling tower and the raised phenomenological model of heat and mass transfer in a selected reference vertical segment of cooling tower. Velocity and temperature fields of the airflow were measured with the aid of a remote control mobile robot unit that was developed to enable measurements in an arbitrary measurement point above the spray zones over the entire cooling tower area. Topological structures of the humid air velocity profiles and temperature profiles above the spray zones were obtained at constant integral parameters of a power plant. Measurement results of temperature and mass flow characteristics of the air and water flows in a selected reference vertical segment of cooling tower are presented in the form of phenomenological dependence. Phenomenological dependence links local cooling tower efficiency, geometrical characteristics of spray elements, and air and water flow rates. In the concluding part, both methods are applied together on a selected segment of cooling tower, and local and integral cooling tower efficiency can be determined. 相似文献
90.