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21.
Constructing inferences during narrative text comprehension. 总被引:1,自引:0,他引:1
Describes a constructionist theory that accounts for the knowledge-based inferences that are constructed when readers comprehend narrative text. Readers potentially generate a rich variety of inferences when they construct a referential situation model of what the text is about. The proposed constructionist theory specifies that some, but not all, of this information is constructed under most conditions of comprehension. The distinctive assumptions of the constructionist theory embrace a principle of search (or effort) after meaning. According to this principle, readers attempt to construct a meaning representation that addresses the reader's goals, that is coherent at both local and global levels, and that explains why actions, events, and states are mentioned in the text. This study reviews empirical evidence that addresses this theory and contrasts it with alternative theoretical frameworks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
It was proposed that thinking about disease-detection behavior would lead to more negative moods than thinking about health-promotion behavior. Detection behaviors produce more negative moods because they can threaten perceptions of good health. In a laboratory study, the initial mood states of 121 participants recruited from undergraduates and the general community were measured using a neutral-words rating procedure. Then participants were randomly assigned to think about performing a disease-detection behavior or a health-promotion behavior. Subsequently, they wrote down their responses to the behavior and evaluated these 35 either positive, negative, or neutral. Finally, the participant's mood was remeasured using both a neutral words-rating procedure and a more traditional bipolar rating measure. Results indicated that thought about disease-detection behavior produced more negative affective responses and more negative mood change than did thought about health-promotion behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
23.
Six cynomolgus monkeys (Macaca fascicularis) learned preoperatively a set of 10 concurrent object discriminations with 24-hr intertrial intervals. Three then had the rhinal cortex removed bilaterally, whereas the other 3 remained as unoperated controls. The animals with ablations were impaired in reacquiring the preoperatively acquired set but subsequently learned without any impairment a new set of 10 discriminations that was presented in the same way. The monkeys with rhinal cortex ablations then failed to learn delayed matching-to-sample, with double sample presentations, in 510 trials, whereas the control animals learned this task in 270 trials on average. The results add to existing evidence that rhinal cortex ablation produces a severe impairment in visual short-term recognition memory and show for the first time that this impairment is accompanied by normal long-term discrimination learning ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
After investigating the financial feasibility (and so abandoning the idea) of providing self-generated electricity using hydro-power, it was recommended that the top priority should be the direct connection of an electricity supply, from the mains grid to the building; this would cost £8800. Thereby, the theatre would receive a relatively unrestricted supply of electricity at cheaper unit tariffs. This improvement should be followed by the most urgent repairs being carried out to the building fabric, at an estimated cost of £6990. These repairs are necessary to ensure the continued integrity of the building's structure, thereby inhibiting the on-going deterioration.
The energy and financial appraisal also suggested a priority listing of overall improvements to the building in order to achieve a significant, economically justifiable reduction in energy demand; the recommended options are estimated to cost in total £39819. However, the capital cost of such an upgrading would only be recouped, and the theatre achieve a sustainable future, if the building were to be used more intensively and for a wider range of activities than at present in order to increase its revenue significantly.
All prices as stated are those at August 1991. 相似文献
25.
A. Cazarr F. Lpinois A. Marty S. Pinel J. Tasselli J. P. Bailb J. R. Morante F. Murray 《Microelectronics Reliability》2003,43(1):111-115
The aim of this paper is to analyze the feasibility of ultrathin packages through the electrical qualification of the technological process used, i.e. mechanical lapping. It considers polysilicon bipolar transistors which thickness can reach values lower than 10 μm. Forward mode and reverse mode characterizations show no significant degradation of pertinent characteristics, thus allowing to find applications in new compact packaging concept. 相似文献
26.
R Pandey J Quinn C Joyner DW Murray JT Triffitt NA Athanasou 《Canadian Metallurgical Quarterly》1996,55(6):388-395
OBJECTIVE: To study the pathogenesis of aseptic loosening: in particular, to determine whether macrophages responding to particles of biomaterials commonly used in arthroplasty surgery for arthritis are capable of differentiating into osteoclastic bone resorbing cells, and the cellular and hormonal conditions required for this to occur. METHODS: Biomaterial particles (polymethylmethacrylate, high density polyethylene, titanium, chromium-cobalt, stainless steel) were implanted subcutaneously into mice. Macrophages were isolated from the foreign body granulomas that resulted, cultured on bone slices and coverslips, and assessed for both cytochemical and functional evidence of osteoclast differentiation. RESULTS: Tartrate resistant acid phosphatase (TRAP) negative macrophages isolated from granulomas containing particles of all types of biomaterial composition were capable of differentiating into TRAP positive cells capable of extensive lacunar bone resorption (assessed by scanning electron microscopy). The presence of both UMR106 rat osteoblast-like cells and 1,25-dihydroxy vitamin D3 was necessary for this to occur. CONCLUSION: All implant materials produce wear particles that are the focus of a heavy foreign body macrophage response in the fibrous membrane between a loose implant component and the host bone undergoing resorption. These findings underline the importance of biomaterial wear particle generation and the macrophage response to different types of biomaterial wear particles in the pathogenesis of aseptic loosening. 相似文献
27.
R. Murray C. Bryan H. Yu S. Lycett 《Journal of Materials Science: Materials in Electronics》1996,7(5):341-345
The potential associated with quantum well (QW) structures is usually assumed to be a step function; this implies a compositional abruptness at each interface. But abrupt interfaces do not occur in practice, especially if one of the atoms segregates during growth. This leads to asymmetries in the QW potentials which could radically affect device performance. 相似文献
28.
The pharmacology, pharmacokinetics, clinical efficacy, adverse effects, and dosage and administration of torsemide are reviewed. Torsemide belongs to the pyridine-sulfonylurea class of loop diuretics. Its primary site of activity is the thick ascending limb of the loop of Henle, where it blocks active reabsorption of sodium and chloride, resulting in diuresis, natriuresis, and other effects. Torsemide has high bioavailability, a relatively long half-life, and a prolonged duration of activity. It is highly protein bound. Clinical trials indicate that torsemide is effective in the treatment of hypertension and of edema and other symptoms in patients with chronic renal failure (CRF), hepatic dysfunction, or congestive heart failure (CHF). Torsemide has infrequent, mild, and transient adverse effects; among the most common are orthostatic hypotension, fatigue, dizziness, and nervousness. The recommended initial oral dosages of torsemide are 10-20 mg/day for CHF, 20 mg/day for CRF, 5 mg/day for hypertension, and 5-10 mg/day (in combination with a potassium-sparing diuretic or aldosterone antagonist) for hepatic cirrhosis. In most patients, the pharmacokinetic advantages of torsemide over other loop diuretics are unlikely to translate into a substantial edge in clinical outcomes, and in practice there may be no cost advantages. Although torsemide does not offer major advantages over other loop diuretics, it may be of benefit in patients who do not respond to or cannot tolerate other agents. 相似文献
29.
MA Heneghan B Cleary M Murray TA O'Gorman CF McCarthy 《Canadian Metallurgical Quarterly》1998,43(6):1356-1361
Thromboembolic events frequently complicate the clinical course of patients with inflammatory bowel disease (IBD). Hereditary thrombophilia may contribute to this tendency. Resistance to activated protein C is the most recently described thrombophilic state and may account for up to 40% of patients with thrombophilia. Thirty-seven patients with IBD were studied (mean age 44 years, range 18-82 years). Three patients had a history of thrombotic episodes. The 37 controls included 23 men and 17 women (mean age 48 years, range 16-89 years). Disease activity was assessed using the Harvey Bradshaw index for patients with Crohn's disease and the Truelove and Witts grading system for patients with ulcerative colitis. Levels of fibrinogen, antithrombin III (ATIII), protein C, protein S, activated protein C resistance (APCR), and the presence of a lupus anticoagulant (LA) were determined. Median ATIII levels in patients with IBD were significantly lower than controls (98% vs 106%, P = 0.007), while fibrinogen was elevated (4.2 vs 3.3 g/liter, P = 0.026) despite quiescent disease activity. LA was detected in 7/37 patients in the IBD group compared to 0/37 controls. (chi2 = 5.68, P = 0.017). No significant difference was observed in levels of inherited thrombophilic factors and in particular APCR between IBD patients and controls. In conclusion, the presence of inherited thrombophilic defects, in particular APCR, is uncommon in patients with IBD and does not merit routine screening. 相似文献
30.
P O'Hara JE Connett WW Lee M Nides R Murray R Wise 《Canadian Metallurgical Quarterly》1998,148(9):821-830
The authors examine weight gains associated with smoking cessation in the Lung Health Study (1986-1994) over a 5-year follow-up period. A cohort of 5,887 male and female smokers in the United States and Canada, aged 35-60 years, were randomized to either smoking intervention or usual care. Among participants who achieved sustained quitting for 5 years, women gained a mean of 5.2 (standard error, 5.0) kg in year 1 and a mean of 3.4 (standard error, 5.5) kg in years 1-5. Men gained a mean of 4.9 (standard error, 4.9) kg in year 1 and a mean of 2.6 (standard error, 5.8) kg in years 1-5. In regression analyses, smoking-change variables were the most potent predictors of weight change. Participants going from smoking to quit-smoking in a given year had mean weight gains of 2.95 kg/year (3.61%) in men and 3.09 kg/year (4.69%) in women. Over 5 years, 33% of sustained quitters gained > or = 10 kg compared with 6% of continuing smokers. Also among sustained quitters, 7.6% of men and 19.1% of women gained > or = 20% of baseline weight; 60% of the gain occurred in year 1, although significant weight gains continued through year 5. The average gains and the high proportions of sustained and intermittent quitters who gained excessive weight suggest the need for more effective early interventions that address both smoking cessation and weight control. 相似文献