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1.
Marsch Lisa A.; Stephens Mary Ann Chutuape; Mudric Timothy; Strain Eric C.; Bigelow George E.; Johnson Rolley E. 《Canadian Metallurgical Quarterly》2005,13(4):293
This study examined (1) predictors of treatment outcome for opioid-dependent participants in a single-site controlled trial comparing methadone, buprenorphine, and LAAM treatments and (2) the extent to which various subpopulations of patients may have more successful outcomes with each medication. The relationships between patient demographics, drug use history, and psychological status and outcome measures of treatment retention, opiate use, and cocaine use were assessed. We believe this study to be the first to demonstrate that predictors of treatment success appear to be largely similar in LAAM, buprenorphine, and methadone treatment for opioid dependence. We did not find any factors that would strongly guide selection of one medication over others. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Emma Murphy Ravi Kuber Graham McAllister Philip Strain Wai Yu 《Universal Access in the Information Society》2008,7(1-2):79-91
In this paper, an empirical based study is described which has been conducted to gain a deeper understanding of the challenges faced by the visually impaired community when accessing the Web. The study, involving 30 blind and partially sighted computer users, has identified navigation strategies, perceptions of page layout and graphics using assistive devices such as screen readers. Analysis of the data has revealed that current assistive technologies impose navigational constraints and provide limited information on web page layout. Conveying additional spatial information could enhance the exploration process for visually impaired Internet users. It could also assist the process of collaboration between blind and sighted users when performing web-based tasks. The findings from the survey have informed the development of a non-visual interface, which uses the benefits of multimodal technologies to present spatial and navigational cues to the user. 相似文献
3.
Path length (A), path width (W) and movement direction (θ) are identified as the main factors affecting visually-controlled movement times in linear paths. Effects of A and W are well described by Drury's ( 1971 . Movements with lateral constraint. Ergonomics, l4 (2), 293-305.) model in which movement time is linearly related to the ratio of A/W. At low A/W values, departure from linearity has been identified but not investigated in detail. Data are presented for both open-loop and feedback-controlled movements in linear paths at 0, 60 and 150° movement directions. Movement amplitude and path width were varied over a wide range to determine the effects of A and (A/W) on movement time. Movements were found to be made ballistically or in open-loop mode when the ratio (A/W) was less than about 8 to 10 and the movement times were linearly related to √A for all angles of movement. Feedback-controlled movements followed Drury's law; ballistic movements had movement speed linear with √A. PRACTITIONER SUMMARY: Many tasks require manoeuvring equipment or devices through a path of limited width. These movements can be made with or without feedback control, depending on the path constraints. The conditions for the two forms of movement are determined in this research. 相似文献
4.
The mirrors of laser interferometric gravitational wave detectors hang from multi-stage suspensions. These support the optics against gravity while isolating them from external vibration. Thermal noise must be kept small so mechanical loss must be minimized and the resulting structure has high-Q resonances rigid-body modes, typically in the frequency range between about 0.3 Hz and 20 Hz. Operation of the interferometer requires these resonances to be damped. Active damping provides the design flexibility required to achieve rapid settling with low noise. In practice there is a compromise between sensor performance, and hence cost and complexity, and sophistication of the control algorithm. We introduce a novel approach which combines the new technique of modal damping with methods developed from those applied in GEO 600. This approach is predicted to meet the goals for damping and for noise performance set by the Advanced LIGO project. 相似文献
5.
In designing human–machine interfaces, it may be necessary for designers to simulate the interface in order to find an acceptable arrangement of controls and displays which have a high expectancy of the relationship between these. We report experiments aimed at determining the level of simulation required to obtain valid measures of stereotype strength relating control movement to display movement. Two experiments are reported, using devices of apparently low and high complexity. Low complexity devices were similar to electronic devices that might be used in the home; the chosen high complexity device was a crane control cabin. For two-dimensional control/display arrangements a low level of simulation generally gave valid results for stereotype strength; a high level of simulation is required for three-dimensional arrangements. With the more complex crane control system, there was a strong effect of the control layout, but little effect of the level of simulation: paper/pencil tests performed as well as computer simulation in giving stereotype strengths. Implications for designers are discussed. 相似文献
6.
It is demonstrated for the first time that an epoxy thermoset resin can be cured at temperatures well below its Tg∞. This study compared the use of a uniform variable frequency microwave (VFM) field to standard oven curing at temperatures above and below Tg∞. Using Tg, tan δ, modulus, and FTIR measurements, it is shown that the reaction of BFDGE with MDA to attain a product with Tg∞ of 133 °C is achieved by VFM at temperatures from 100 to 140 °C; in contrast, the thermal cure normally requires 170 °C to attain the same Tg∞ and the same extent of cure. By following the pregel cure reaction with 13C‐NMR spectroscopy, it was determined that the lower cure temperatures of VFM cure predominately lead to chain extension and smaller amounts of crosslinking compared to the thermal cure. To explain these results, it is suggested that, after gelation, with VFM cure there is higher mobility from dipole rotations that continues the cure to completion without vitrification. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44222. 相似文献
7.
Alessia Costa Barbara Rani Thomaz F. S. Bastiaanssen Francesco Bonfiglio Eoin Gunnigle Gustavo Provensi Moira Rossitto Marcus Boehme Conall Strain Clara S. Martínez Patrizio Blandina John F. Cryan Sophie Lay Renato Corradetti Maria Beatrice Passani 《International journal of molecular sciences》2022,23(2)
Exposure to repeated social stress may cause maladaptive emotional reactions that can be reduced by healthy nutritional supplementation. Histaminergic neurotransmission has a central role in orchestrating specific behavioural responses depending on the homeostatic state of a subject, but it remains to be established if it participates in the protective effects against the insults of chronic stress afforded by a healthy diet. By using C57BL/6J male mice that do not synthesize histamine (Hdc−/−) and their wild type (Hdc+/+) congeners we evaluated if the histaminergic system participates in the protective action of a diet enriched with polyunsaturated fatty acids and vitamin A on the deleterious effect of chronic stress. Behavioural tests across domains relevant to cognition and anxiety were performed. Hippocampal synaptic plasticity, cytokine expression, hippocampal fatty acids, oxylipins and microbiota composition were also assessed. Chronic stress induced social avoidance, poor recognition memory, affected hippocampal long-term potentiation, changed the microbiota profile, brain cytokines, fatty acid and oxylipins composition of both Hdc−/− and Hdc+/+ mice. Dietary enrichment counteracted stress-induced deficits only in Hdc+/+ mice as histamine deficiency prevented almost all the diet-related beneficial effects. Interpretation: Our results reveal a previously unexplored and novel role for brain histamine as a mediator of many favorable effects of the enriched diet. These data present long-reaching perspectives in the field of nutritional neuropsychopharmacology. 相似文献
8.
The past few years has seen a change in the size of newspapers, with publishers moving to a smaller size format. Five ‘standard’ newspaper sizes are used in different countries: Broadsheet, Rhensch, Tabloid, Tall Tabloid and Berliner. These papers vary in both width and height of pages and hence there are implications for human reading comfort, which may be dependent on reading location such as on a lounge chair or on a train. Experiments were carried out to determine preferences for the different sizes and to relate these preferences to the geometric characteristics of the newspapers. For both comfortable and cramped/uncomfortable reading conditions, the rank order of preference for paper types was, from least to most-preferred, Broadsheet, Rhensch, Berliner, Tall Tabloid and Tabloid. Preferences were much stronger when determined in cramped/uncomfortable reading conditions, where most comparisons were significantly different. There was good correlation between participant ratings on several scales and preference, where most factors were related to comfort of holding and controlling the paper. 相似文献
9.
10.
M. Kerry Garrett John J. Strain Marion D. B. Allen 《Journal of the science of food and agriculture》1976,27(7):603-611
The composition of the product of algal culture in the liquid phase of slurry has been examined. The material consists of cells of the cultured alga (Chlorella vulgaris) together with those of the endogenous microbial community, and contains approximately 42% true protein, 23% carbohydrate, 16% lipid and 9% nucleic acid. The protein is deficient in the sulphur amino acids but rich in lysine. The latter feature appears to be related to the presence of hexanoic acid in slurry. The endogenous microorganisms do not make a significant direct contribution to the composition of material harvested after algal culture. Light and temperature have only slight effects upon composition of the harvested material. 相似文献