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91.
This study examined how a previous episode of depression is related to daily pain and reactions to pain among individuals with fibromyalgia, a chronic pain syndrome. Seventy-one women with fibromyalgia (including 30 who were previously depressed) rated their pain and mood 3 times daily for 30 days. Each night, participants rated the extent to which they responded to pain by catastrophizing, how much control they had over that day's pain, their ways of coping with pain that day, and the effectiveness of their coping efforts. Multivariate multilevel regression models revealed that after controlling for neuroticism and current depressive symptoms, formerly depressed and never-depressed individuals differed in how they coped with increased pain and in how they appraised the efficacy of their coping efforts. Formerly depressed participants who also reported more current depressive symptoms showed a greater decline in pleasant mood on more painful days than did formerly depressed participants who were experiencing fewer current depressive symptoms. These findings illustrate how a history of depression can be captured in the dynamics of daily life. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
The authors applaud A. S. Green, E. Rafaeli, N. Bolger, P. E. Shrout, and H. T. Reis's (2006) response to one-sided comparisons of paper versus electronic (plastic) diary methods (see record 2006-03820-006) and hope that it will stimulate more balanced considerations of the issues involved. The authors begin by highlighting areas of agreement and disagreement with Green et al. The authors review briefly the broader literature that has compared paper and plastic diaries, noting how recent comparisons have relied on study designs and methods that favor investigators' allegiances. The authors note some sorely needed data for the evaluation of the implications of paper versus plastic for the internal and external validity of research. To facilitate evaluation of the existing literature and assist in the design of future studies, the authors offer a balanced comparison of paper and electronic diary methods across a range of applications. Finally, the authors propose 2 study designs that offer fair comparisons of paper and plastic diary methods. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
We combined remote sensing and in-situ measurements to estimate evapotranspiration (ET) from riparian vegetation over large reaches of western U.S. rivers and ET by individual plant types. ET measured from nine flux towers (eddy covariance and Bowen ratio) established in plant communities dominated by five major plant types on the Middle Rio Grande, Upper San Pedro River, and Lower Colorado River was strongly correlated with Enhanced Vegetation Index (EVI) values from the Moderate Resolution Imaging Spectrometer (MODIS) sensor on the NASA Terra satellite. The inclusion of maximum daily air temperatures (Ta) measured at the tower sites further improved this relationship. Sixteen-day composite values of EVI and Ta were combined to predict ET across species and tower sites (r2 = 0.74); the regression equation was used to scale ET for 2000-2004 over large river reaches with Ta from meteorological stations. Measured and estimated ET values for these river segments were moderate when compared to historical, and often indirect, estimates and ranged from 851-874 mm yr− 1. ET of individual plant communities ranged more widely. Cottonwood (Populus spp.) and willow (Salix spp.) stands generally had the highest annual ET rates (1100-1300 mm yr− 1), while mesquite (Prosopis velutina) (400-1100 mm yr− 1) and saltcedar (Tamarix ramosissima) (300-1300 mm yr− 1) were intermediate, and giant sacaton (Sporobolus wrightii) (500-800 mm yr− 1) and arrowweed (Pluchea sericea) (300-700 mm yr− 1) were the lowest. ET rates estimated from the flux towers and by remote sensing in this study were much lower than values estimated for riparian water budgets using crop coefficient methods for the Middle Rio Grande and Lower Colorado River.  相似文献   
94.
Iain Milne  Glenn Rowe 《Software》2005,35(15):1477-1493
Although the principles of writing compilers and interpreters are well known, we have found that the ideas needed to develop an interpreter for the express purpose of allowing direct interaction with the running code do not yet appear to have been published in an academic context. We describe a programming method that can be used for the production of an interpreter for common object‐oriented languages such as C++, Java and C#. The main purpose of the interpreter is to parse short, relatively simple programs and allow direct interaction between the user and the running code. Such a system is useful for projects such as OGRE, which is an educational tool allowing students to visualize in three‐dimensional graphics the state of a program as it runs. The interpreter works by first parsing the source code and building up a data structure capable of representing the program's source code in a form that can be used to both run the program and extract detailed information from the running program. This extraction allows for novel uses of the interpreter, such as forming the basis for a visualization system that must display and provide such information to the user as they watch their executing program. This paper considers the construction of such an interpreter specifically for C++, but the principles should be the same for other similar languages such as Java and C#. We cover the main tasks required of the programmer to create and use the data structure, highlighting areas such as its design, initial construction during parsing, and techniques required to use it for interpretation. These include the ability for the data structure to intelligently clone subsets of itself when multiple copies of one of its elements are required by the running program, how it handles C++'s complicated function overloading and overriding rules, and how inheritance and polymorphism can be supported. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
95.
The objective was to investigate the feasibility of using near infrared reflectance spectroscopy to determine the composition of samples generated in situ. Five alfalfa and five orchardgrass hays of differing maturities were incubated for 0, 6, 24, 48, and 72 h (Experiment 1) or for 0, 2, 4, 8, 12, 24, 48, and 96 h (Experiment 2) in rumen-fistulated, lactating cows, using nylon bags. After washing to remove rumen contents, samples were analyzed using a nonrotating circular cell in a scanning monochromator. All samples then were dried at 55 degrees C and analyzed for CP and ADF by wet chemistry and rescanned in the dry state. The degree of DM digestion of the original sample was calculated from duplicate bags. Results for spectral analysis of dried samples (Experiment 1), with one-half the samples for validation, were typical of results found for dry forages. The results for scanning wet samples were less accurate than for dry ones. Analysis of samples from Experiment 2 by equations developed in Experiment 1 often resulted in extremely large biases, but these were corrected by including six samples of each forage from Experiment 2 in the calibration set (from Experiment 1) and redeveloping the equations. Although it is possible to use near infrared reflectance spectroscopy to determine the composition of wet samples generated in situ, results are more accurate if the samples are scanned after drying.  相似文献   
96.
A discrete variable structure tracking controller is developed for a wide class of linear and nonlinear systems with structured uncertainties. The proposed controller uses a pole placement controller as a kernel and compensates for the errors associated with uncertainties. The algorithm is computationally efficient and can be easily used as a robust backup controller for the higher performance, but sensitive, adaptive algorithms.  相似文献   
97.
Measured the visible persistence of illusory contours (ICs) in 2 experiments. In Exp 1, persistence was determined among 12 Ss for IC squares presented for 50 msec. Exp 2, with 10 Ss, varied target duration from 50 to 1,000 msec. For the control figures, visible persistence decreased with increasing target duration. However, with the IC targets, persistence increased sharply with increasing target duration and then decreased. Results suggest that the time it takes for the visual system to construct the subjective contour yields an overall increase in persistence, and this ongoing processing can be seen over long target durations. Data support the existence of cortical components of visible persistence. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
Two studies were conducted to assess the dimensionality of supervision. The purpose of Study 1 was to identify the salient dimensions of supervision from the counselor trainee's perspective and to determine if dimensions for trainees corresponded to the dimensions found previously for supervisors. In doing so the dimensionality and construct validity of Bernard's (1979) model was examined by using 15 doctoral trainees. For Study 2 Bernard's model was expanded to incorporate the self-supervisor role and was tested in combination with Littrell, Lee-Borden, and Lorenz's (1979) model. Counselor trainees from a master's (n?=?25) and a doctoral (n?=?23) program participated. The three dimensions that emerged in Study 1 and in Study 2 were remarkably consistent in content and label across the two studies. In terms of dimensionality, Bernard's model and the extended model were modestly supported, whereas Littrell et al.'s model received minimal support. Little evidence was found to suggest that trainees from master's and doctoral programs differed at all in terms of their cognitive maps of supervision. Implications and limitations of the studies were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
The efficacy of nonreamed nailing as the treatment of choice of unstable blunt tibial diaphyseal fractures was studied. From March 1, 1990, through August 31, 1991, 72 patients with 74 fractures that required fixation were treated. One patient died and six were lost to follow-up, leaving 65 patients with 67 fractures. Follow-up averaged 21 months (range 5-43). Fisher's exact and logistic regression analyses were used to compare grades of open fractures, comminution as classified by Winquist, and dynamic and static nailings. The failure rates of 51 titanium and 16 stainless steel nails were compared. Times to union were compared by the log rank statistic method. The average time to union was 32 weeks with 26 (39%) additional operations required to achieve union; 13 dynamizations (12 successful), 12 exchange nailings (11 successful), and one plate and bone graft. The rate of reconstructive procedures to achieve union was a more sensitive indicator of difficulties achieving union than was time to union. Reoperation rates were 33% for closed or grade I and II fractures compared with 46% for grade III fractures (NS). Among closed grade I and II static versus dynamic nailing, times to union were 36 versus 25 weeks (p < 0.01), and the reoperation rates were 44% versus 13% (p < 0.04). Winquist I and II fractures required a 24% reoperation rate versus 53% for grade III and IV and segmental fractures (p < 0.01). Static locked fractures required a 48% reoperation rate versus 12% for dynamic locked fractures (p < 0.01). A logistic regression analysis demonstrated that locking mode was the most important factor in determining reoperation rates. Fifteen additional reoperations for infection, broken or painful implants, or to remodel bones that united with an incomplete circumference of cortex were performed. With an additional 12 elective nail removals, the total reoperations numbered 53 (79%). Titanium alloy nails had a 2% failure rate versus 25% for stainless steel nails (p < 0.01). Two of 28 (7%) grade III fractures became infected. All fractures united within 10 degrees of normal alignment and 1 cm of length. Nine (13%) united with an incomplete cortical circumference, refractory to dynamization and full weight bearing. Thirteen of the 58 (22%) fractures available for an evaluation of ankle motion were symptomatic, with < 10 degrees of dorsiflexion.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
100.
The SHAPE-assisted decision-making procedure (C. E. J. H?rtel & G. F. H?rtel, 1997) is examined. The model provides a simple strategy for making decisions under time pressure, stress, or cognitive load. The approach is useful under such conditions because it encourages decision makers to examine the problem, identify a preferred alternative, assess the alternative as time permits, take action, and evaluate the results. The model may be less appropriate for important decisions that are made under low levels of time pressure or stress, have nonintuitive solutions, require thorough consideration of alternatives, or involve low levels of expertise. Implications of the SHAPE model for future research and practice are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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