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91.
The view of iconic memory as a precategorical, high-capacity, quickly decaying visible memory has recently come under attack (e.g., M. Coltheart, 1980). Distinctions have been drawn between visible persistence, or the phenomenal trace of an extinguished stimulus, and informational persistence, knowledge about the visual properties of the stimulus. Two alternative conceptions of informational persistence were tested in 3 experiments with 13 university students and the present authors. One conception is that visual information persists in a visual memory that begins at stimulus offset and lasts for 150–300 msec, independently of exposure duration. The 2nd conception is that informational persistence arises from a nonvisual memory that contains spatial coordinates for displayed items along with identity codes for those items. In the experiments, 3?×?3 letter arrays were presented for durations ranging from 50 to 500 msec. A single character mask presented at varying intervals after array offset cued report of an entire row of the array. Comparison of the cued row's masked and unmasked letters revealed that spatially specific visual (i.e., maskable) information persisted after stimulus offset, regardless of exposure duration. This result favors the visual conception of informational persistence. There was also support, however, for the nonvisual conception: Accuracy increased and item intrusion errors decreased as stimulus duration increased. Implications for models of informational persistence and for transsaccadic integration during reading are discussed. (47 ref) (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
92.
93.
We derive an effective single-band Hubbard type Hamiltonian for CuO2 planes. The Hamiltonian includes both electron-electron repulsion and electron-phonon coupling to oxygen vibrational modes. We start with first-principles density functional theory parameters and then map onto a single-band model. Unlike previous mappings to a single-band Hamiltonian, ours explicitly preserves the Fermi surface shape and matrix elements of the many-band Hamiltonian. We consider both in-plane oxygen breathing modes as well as out-of-plane tilting modes. The latter modes have a quadratic electron-phonon coupling, and are also highly anharmonic in La2CuO4 based superconductors. The coupling to breathing modes is too small to account for highT
c, while the coupling to quadratic modes is much stronger even though they would be neglected in a standard Migdal-Eliashberg approach to superconductivity. 相似文献
94.
F. L. Schmidt and J. E. Hunter (1989) critiqued the within-group interrater reliability statistic (rwg) described by L. R. James et al (1984). S. W. Kozlowski and K. Hattrup (1992) responded to the Schmidt and Hunter critique and argued that rwg is a suitable index of interrater agreement. This article focuses on the interpretation of rwg as a measure of agreement among judges' ratings of a single target. A new derivation of rwg is given that underscores this interpretation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Perri Michael G.; McAllister David A.; Gange James J.; Jordan Randall C.; McAdoo W. George; Nezu Arthur M. 《Canadian Metallurgical Quarterly》1988,56(4):529
This study evaluated the effectiveness of four posttreatment programs designed to enhance the long-term maintenance of weight loss. Mildly and moderately obese adults (N?=?123) were randomly assigned to one of the following five conditions: (a) behavior therapy only; (b) behavior therapy plus a posttreatment therapist-contact maintenance program; (c) behavior therapy plus posttreatment therapist contact plus a social influence maintenance program; (d) behavior therapy plus posttreatment therapist contact plus an aerobic exercise maintenance program; or (e) behavior therapy plus posttreatment therapist contact plus both the aerobic exercise and social influence maintenance programs. All posttreatment programs were conducted in 26 biweekly sessions during the year following behavioral treatment for obesity. At an 18-month follow-up evaluation, all four conditions that combined behavior therapy with a posttreatment maintenance program yielded significantly greater long-term weight losses than behavior therapy alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
S Sidney B Sternfeld SS Gidding DR Jacobs DE Bild A Oberman WL Haskell RS Crow JM Gardin 《Canadian Metallurgical Quarterly》1993,25(8):911-916
Symptom-limited, graded exercise treadmill testing was performed by 4,968 white and black adults, ages 18-30 yr, during the baseline examination for the Coronary Artery Risk Development in Young Adults (CARDIA) study. Compared with nonsmokers, the mean exercise test duration of smokers was 29-64 s shorter depending on race/gender group (all P < 0.001), but mean duration to heart rate 130 (beats.min-1) ranged from 20-50 s longer (P < 0.05). In each race/gender group, test duration to heart rates up to 150 was 15-35 s longer (P < 0.05) in smokers than in nonsmokers after adjustment for age, sum of skinfolds, hemoglobin, and physical activity score. The mean maximum heart rate was lower in smokers than in nonsmokers (difference ranging from 6.7 beats.min-1 in white men to 11.2 beats.min-1 lower in black women, P < 0.001), although maximum rating of perceived exertion was nearly identical in smokers and nonsmokers. Chronic smoking appears to blunt the heart rate response to exercise, so that exercise duration to submaximal heart rates is increased even though maximal performance is impaired. This may result from downloading of beta-receptors caused by smoking. Smoking status should be considered in the evaluation of physical fitness data utilizing submaximal test protocols, or else the fitness of smokers relative to nonsmokers is likely to be overestimated. 相似文献
97.
98.
DE Patterson CA Raviola EA D'Orazio C Buch KD Calligaro MJ Dougherty DA DeLaurentis 《Canadian Metallurgical Quarterly》1996,24(6):1030-1033
This case report details the multidisciplinary treatment of peripartum left iliac vein thrombosis using percutaneous catheter-directed urokinase thrombolysis and balloon thromboplasty. Enhanced chances for long-term patency and the normalization of venous function make these minimally invasive procedures accepted options for the treatment of iliofemoral deep venous thrombosis in selected peripartum patients. 相似文献
99.
Ockene Judith K.; Kristeller Jean; Pbert Lori; Hebert James R.; Luippold Rose; Goldberg Robert J.; Landon Joan; Kalan Kathryn 《Canadian Metallurgical Quarterly》1994,13(3):278
Patterns of smoking cessation using 6- and 12-mo follow-up data are reported for 1,261 primary care patients randomized to 3 physician-delivered smoking interventions: advice only (AO), counseling (CI), and counseling plus availability of nicotine-containing gum (CI?+?NCG). One-week point-prevalence cessation rates at 12 mo did not differ among the interventions: AO (15.2%), CI (12.9%) and CI?+?NCG (16.7%). However, maintained cessation rates (abstinent at both 6 and 12 mo) increased with intervention intensity: AO (6.0%), CI (7.8%), and CI?+?NCG (10.0%): Test of trend χ–2?=?5.06, p?=?.02. CI?+?NCG was significantly higher than AO (p?=?.02). The findings support the following conclusions: Brief physician delivered intervention with availability of nicotine-containing gum can have a beneficial long-term effect on smoking cessation, and cohort data as well as point-prevalence rates are important when assessing the long-term impact of lifestyle interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Examined the emotional similarity hypothesis, a derivation from social comparison theory, which predicts that increasing fear should lead to greater affiliation with someone who is awaiting the same threat (and who therefore is of relatively similar emotional status) relative to someone who has already experienced the threat (and who therefore is of relatively dissimilar emotional status). Results failed to support the emotional similarity hypothesis and in so doing challenged the importance of emotional comparison as a determinant of verbal affiliation under threat. Cognitive clarity concerns instead seemed to account better for the observed effects on verbal affiliation. Supplementary analyses of nonverbal affiliation (facial glances) likewise ran counter to an emotional similarity prediction. Effects of affiliation on anxiety were also examined. Previous conclusions regarding the pattern and causes of affiliation under threat that have relied on the affiliate-choice paradigm are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献