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131.
This study examined the role of catastrophizing (i.e. a tendency to exaggerate the threat value of potentially painful situations) in predicting pain experience during dental hygiene treatment. Participants in the research were 100 patients undergoing scaling and/or root planing procedures at Dalhousie University's Dental Clinic. Following treatment, participants completed the Pain Catastrophizing Scale, a measure of emotional distress, a pain scale, and the Dental Anxiety Scale-Revised. Participants who scored above the median on the Pain Catastrophizing Scale were classified as catastrophizers, participants who scored below the median were classified as noncatastrophizers. Results showed that catastrophizers reported significantly more dental anxiety, emotional distress and pain than noncatastrophizers; and that distress reactions were more pronounced in men that in women. Discussion focuses on the importance of addressing psychological factors in dental hygiene practice, particularly as they relate to reactions to dental hygiene procedures, and avoidance of dental care. 相似文献
132.
NR Every LS Parsons SD Fihn EB Larson C Maynard AP Hallstrom JS Martin WD Weaver 《Canadian Metallurgical Quarterly》1997,96(6):1770-1775
BACKGROUND: Previous studies have documented the strong association between availability of on-site cardiac catheterization facilities and increased use of coronary angiography in patients with acute myocardial infarction (AMI). Although these studies have shown little influence of the availability of catheterization labs on hospital mortality, no long-term follow-up has been reported. METHODS AND RESULTS: From a cohort of 12,331 AMI patients admitted to 19 Seattle area hospitals, we compared long-term outcome in 7985 patients admitted to hospitals with and 4346 patients admitted to hospitals without on-site catheterization labs. During the index hospitalization, patients admitted to hospitals with on-site catheterization were more likely to undergo coronary angiography (67.1% versus 39.3%, P<.0001), coronary angioplasty (32.5% versus 13.2%, P<.0001), or coronary bypass surgery (12.5% versus 9.5%, P<.0001). At 3-year follow-up, patients admitted to hospitals with on-site catheterization labs were more likely to undergo postdischarge angiography (19.2% versus 15.2%, P=.0001) and coronary angioplasty (11.6% versus 8.2%, P<.0001). This was associated with approximately $2500.00 per patient in higher cumulative costs. Despite this higher rate of procedure use, there was no association between admission to a hospital with on-site catheterization facilities and lower long-term mortality (multivariate hazard ratio, 1.0; 95% CI, 0.93 to 1.1., the hazard being associated with admission to hospitals with on-site catheterization facilities). CONCLUSIONS: In an urban area with unconstrained patient transfer mechanisms and high overall cardiac procedure use rates, AMI patients admitted to hospitals without on-site catheterization facilities were managed with fewer procedures during hospitalization and follow-up. This more conservative treatment approach was not associated with any observed increase in long-term mortality. 相似文献
133.
A statnet Tutorial 总被引:1,自引:0,他引:1
Goodreau SM Handcock MS Hunter DR Butts CT Morris M 《Journal of statistical software》2008,24(9):1-27
The statnet suite of R packages contains a wide range of functionality for the statistical analysis of social networks, including the implementation of exponential-family random graph (ERG) models. In this paper we illustrate some of the functionality of statnet through a tutorial analysis of a friendship network of 1,461 adolescents. 相似文献
134.
An improved closed-form approximation to the inverse black body radiation problem at microwave frequencies 总被引:1,自引:0,他引:1
A function is derived which approximates Planck's black body radiation law more closely at microwave frequencies than either the Rayleigh-Jeans or the recent Hamid-Ragheb approximations. The function leads to an improved closed-form approximation to the inverse black body radiation problem in the microwave region. 相似文献
135.
Christopher J. Howard Brett A. Hunter Dae-Joon Kim 《Journal of the American Ceramic Society》1998,81(1):241-243
A survey of the available data on the oxygen positions in various tetragonal zirconias reveals a simple, approximate relationship between the departure of the oxygen from the position it would have in the ideal fluorite structure, and the tetragonality ( c/a ) of the material. This relationship can be understood on the basis that the two oxygen—oxygen contact distances are very nearly equal. The relationship may be used to estimate the oxygen position from the lattice parameters, and from that all the bond lengths in the structure. 相似文献
136.
Recent advances in cognitive science and neuroscience (CSN) have allowed scientists to begin to address questions that were heretofore considered the province of the humanities. Growing out of a 2007 conference at Bucknell University, this volume explores recent research in many different areas that combines the methods and perspectives of both the humanities and CSN. This introduction argues that the barriers to such work (such as the opposition between objective scientific research and subjective humanistic research) are purely of our own making and in no way absolute; it further asserts that the articles herein demonstrate that the potential benefits of interdisciplinary study far outweigh the risks. There is no fixed method for interdisciplinarity. Its success depends on respect for the particulars of each research question and the imagination to see what combinations of different disciplines might work best. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
137.
A discretely tunable passive microwave photonic delay line based on a multichannel grating matrix is demonstrated. This topology demonstrates high-speed high-resolution time delaying of microwave signals, along with requiring a reduced number of discrete gratings for any given delay range. High channel isolation and low insertion loss are also features of this topology, making this suitable for many wideband applications. 相似文献
138.
139.
Localization and speciation of chromium in subterranean clover using XRF, XANES, and EPR spectroscopy 总被引:2,自引:0,他引:2
Howe JA Loeppert RH DeRose VJ Hunter DB Bertsch PM 《Environmental science & technology》2003,37(18):4091-4097
Optimization of phytoremediation and assessment of potential health hazards from metals in the environment requires an understanding of absorption, localization, and transport of the target metal by plants. The objectives of this study were to localize Cr and determine the oxidation state and possible complexation mode of Cr in intact plant tissue by means of XANES, synchrotron XRF microprobe spectroscopy, and EPR spectroscopy. Subterranean clover (Trifolium brachycalycinum) was grown hydroponically with Cr(VI) (0.04-2.0 mmol L(-1)) and compared with plants grown without Cr and with inorganic Cr(III) and various Cr(III)-organic sources. The uptake, translocation, and form of Cr in the plant were dependent on the form and concentration of supplied Cr. Chromium was found predominately in the +3 oxidation state, regardless of the Cr source supplied to the plant, though at high Cr(VI) treatment concentrations, Cr(VI) and Cr(V) were also observed. At low Cr(VI) concentrations, the plant effectively reduced the toxic Cr(VI) to less toxic Cr(III), which was observed both as a Cr(III) hydroxide phase at the roots and as a Cr(III)-organic complex in the roots and shoots. At low Cr(VI) treatment concentrations, Cr in the leaves was observed predominately around the leaf margins, while at higher concentrations Cr was accumulated at leaf veins. 相似文献
140.
Rex M. Brennan E. Anthony Hunter D. Donald Muir 《Food research international (Ottawa, Ont.)》2003,36(9-10):1015-1020
The effects of processing treatments (heat, sucrose addition) on the sensory quality of blackcurrant juices prepared from two genetically diverse cultivars (Ben Lomond and Ben Alder) were examined using sensory profiling. Sucrose level had the largest effect on the sensory profile, with heating and cultivar having smaller but still significant effects. Some interaction between sucrose level and heating of the juices was observed in the sensory profile. The results indicate that selection of preferred genotypes remains an important breeding objective in blackcurrant improvement programmes, since the sensory attributes associated with genotype persist, despite processing effects, in the extracted juice. 相似文献