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排序方式: 共有217条查询结果,搜索用时 15 毫秒
91.
Vellutino Frank R.; Scanlon Donna M.; Tanzman Melinda S. 《Canadian Metallurgical Quarterly》1988,42(2):216
Examined whether differences between poor and normal reading children on lexical memory tasks may be attributed to semantic development, using 80 2nd and 6th graders. Ss were presented with 4 lists of taxonomic categories and were asked to recall items under (a) noncued and random conditions, with Ss instructed to recall as many items as possible and (b) cued and blocked conditions, with Ss told to recall items in a category. All Ss performed better with category cues. Group differences on category recall were more reliable at Grade 6, suggesting that facility in accessing taxonomic categories may differentiate poor and normal readers more reliably at older age levels. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
The negative suggestion effect: Pondering incorrect alternatives may be hazardous to your knowledge.
Brown Alan S.; Schilling Hildur E. H.; Hockensmith Melinda L. 《Canadian Metallurgical Quarterly》1999,91(4):756
This article examines the negative suggestion effect, or the impact of exposure to incorrect alternatives on memory for correct information. All experiments used the following design: (a) cued-recall test of general facts (e.g., "second smallest planet") with immediate correct feedback, (b) interpolated exposure to incorrect information related to Test 1 items, and (c) a second test over the same items as Test 1. Test 2 was either multiple choice or cued recall and was given either immediately or 1 week after interpolation. Three experiments confirmed the existence of negative suggestion: Exposure to misinformation hindered subsequent performance on those items, relative to noninterpolated control items. The magnitude of this decrement is unrelated to retention interval, type of second test, number of incorrect alternatives exposed, and number of repetitions of incorrect alternatives. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
We evaluated the performance of 6 adult rhesus monkeys (Macaca mulatta) on object permanence tasks. In Experiment 1, monkeys received search tasks that correspond to Stages 4, 5, and 6 of object permanence. Subjects were successful on tasks of visible displacements (Stages 4 and 5) but failed to find the object in invisible displacements (Stage 6). The monkeys adopted a search strategy of investigating a specific hiding location. In Experiment 2, monkeys were given a second opportunity to find the object if they investigated a location that was part of the displacement on their first search. Subjects relied on the same search strategy identified in Experiment 1. In Experiment 3, the experimenter hid the object in her hand rather than a container. The monkeys failed to recover the object, and individual differences were found in the strategies used. These results suggest that the upper limit of object permanence in rhesus monkeys is Stage 5. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Argues that materialism, specifically eliminative materialism, is dependent on the immaterial language and immaterial experiential realm for its meaning. The mind/body dualism has been a bane to psychology. Eliminative Materialists eliminate the immaterial mind from study, thereby rejecting the dualism. However, in assuming biology reveals everything about human experience, eliminative materialists are faced with a presupposed dualism: biological language, which is supposed to replace any psychological language, is necessarily correlated with and dependent upon meaning in the psychological language. Further, the nature of identity between the biological and psychological is either meaningless tautology or a dualism of explanatory realms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
The novel electronic properties of graphene, including a linear energy dispersion relation and purely two-dimensional structure, have led to intense research into possible applications of this material in nanoscale devices. Here we report the first observation of saturating transistor characteristics in a graphene field-effect transistor. The saturation velocity depends on the charge-carrier concentration and we attribute this to scattering by interfacial phonons in the SiO2 layer supporting the graphene channels. Unusual features in the current-voltage characteristic are explained by a field-effect model and diffusive carrier transport in the presence of a singular point in the density of states. The electrostatic modulation of the channel through an efficiently coupled top gate yields transconductances as high as 150 microS microm-1 despite low on-off current ratios. These results demonstrate the feasibility of two-dimensional graphene devices for analogue and radio-frequency circuit applications without the need for bandgap engineering. 相似文献
96.
Koppel S Charlton JL Fitzharris M Congiu M Fildes B 《Accident; analysis and prevention》2008,40(2):657-666
This study investigated the factors associated with the premature graduation into seatbelts for Australian children aged 4-11 years. From 699 child restraint use questionnaires, 195 children were identified as meeting the booster seat height-weight criteria (height: 100-145 cm and weight: 14-26 kg). Of these children, 44% were correctly traveling in a booster seat, while 56% had been moved prematurely into a seatbelt. A multivariable logistic regression model showed that there were a number of key predictors associated with the premature graduation to seatbelts. For example, children who were moved prematurely into a seatbelt were more likely to be older, have other children travelling in the vehicle and have younger parents compared to children appropriately restrained in a booster seat. In addition, there was a significant interaction between vehicle type and parent's household income. Based on the findings of this study, a number of recommendations are made for strategies to enhance appropriate restraint use for this age group, as well as for future research. 相似文献
97.
Hayman MM Anantheswaran RC Knabel SJ 《International journal of food microbiology》2007,115(2):220-226
The aim of this study was to explore the effect of a wide range of growth temperatures, growth phases and plating media on the inactivation of Listeria monocytogenes by high pressure processing (HPP). In part one, L. monocytogenes was grown to mid-stationary phase at 4, 15, 25, 35 or 43 degrees C, inoculated into whole UHT milk at approximately 10(7) CFU/ml and high pressure processed at 400 MPa at room temperature (20-25 degrees C). Afterward, the HPP milk was plated on Tryptic Soy Yeast Extract Agar (TSYEA) and Modified Oxford Agar (MOX) to determine the degree of injury. For part two, cells were grown to mid-exponential, late-exponential or mid-stationary phase at 15 or 43 degrees C and processed in the same way. Time to reach a 5-log reduction was determined and data were analysed by ANOVA. The results from part one showed that both growth temperature and plating medium had a significant effect (P < 0.001) on the inactivation of stationary phase L. monocytogenes by HPP. Tukey's pairwise comparisons revealed that the effects of all temperatures, except 35 and 43 degrees C, were significantly different (P < 0.05). Cells grown at 15 degrees C were most sensitive to HPP, followed by cells grown at 4, 25 or 35 degrees C, with cells grown at 43 degrees C appearing to be the most resistant. Inactivation of cells grown at 4, 15 or 25 degrees C followed first order kinetics, whereas cells grown at 35 or 43 degrees C displayed non-linear inactivation kinetics due to tailing. In part two, both growth phase and plating medium had significant effects on the inactivation (P < or = 0.001) of L. monocytogenes by HPP. Cells grown at 15 degrees C to mid-stationary phase were the most pressure-resistant when tested on both media, and were significantly more resistant (P < 0.05) than cells grown at the same temperature to the other two phases of growth. There was no significant difference between mid- and late-exponential phase cells grown at 15 degrees C. When cells were grown at 43 degrees C, mid-exponential phase cells were significantly more sensitive (P < 0.05) than either late-exponential or mid-stationary phase cells, with no difference between late-exponential or mid-stationary phase cells. It was postulated that membrane composition, stationary phase proteins and/or stress proteins may affect pressure resistance. 相似文献
98.
Abstract It certainly is true that George Bernard Shaw, the Irish playwright and essayist, was fond of provocation and paradox. Yet, as our epigraph suggests, his writings always build on a core of truth. For Shaw, truth was defined by his socialism as well as by relations among art, science, and religion. These ideas merge in his provocative essay of 1902, ‘The Unmechanicalness ofPhotography’,2 written when the focus of his photographic criticism was shifting from primarily political! economic concerns to a synthesis of social, aesthetic, metaphysical, and scientific ideas. Although his essay has been reprinted since 1902,3 the broader context that lends meaning to Shaw's otherwise peculiar remarks about painting and photography has not been explored sufficiently; that is our goal here. 相似文献
99.
Boosting Affinity by Correct Ligand Preorganization for the S2 Pocket of Thrombin: A Study by Isothermal Titration Calorimetry,Molecular Dynamics,and High‐Resolution Crystal Structures 下载免费PDF全文
Dr. Eggert H. Rühmann Melinda Rupp Dr. Michael Betz Prof. Dr. Andreas Heine Prof. Dr. Gerhard Klebe 《ChemMedChem》2016,11(3):309-319
Structural preorganization to fix bioactive conformations at protein binding sites is a popular strategy to enhance binding affinity during late‐stage optimization. The rationale for this enhancement relates to entropic advantages assigned to rigidified versus flexible ligands. We analyzed a narrow series of peptidomimetics binding to thrombin. The individual ligands exhibit at P2 a conformationally flexible glycine, more restricted alanine, N‐methylglycine, N‐methylhomoalanine, and largely rigidified proline moiety. Overall, affinity was found to increase by a factor of 1000, explained partly by an entropic advantage. All ligands adopt the same binding mode with small deviations. The residual mobility of the bound ligands is decreased across the series, and a protein side chain differs in its order/disorder behavior along with changes in the surface‐water network pattern established across the newly generated protein–ligand surfaces. The enthalpy/entropy inventory displays a rather complex picture and emphasizes that thermodynamics can only be compared in terms of relative differences within a structurally similar ligand series. 相似文献
100.
Offshore wind speed estimates from a high‐resolution rapidly updating numerical weather prediction model forecast dataset 下载免费PDF全文
In association with the Department of Energy–funded Position of Offshore Wind Energy Resources (POWER) project, we present results from compositing a 3‐year dataset of 80‐m (above ground level) wind forecasts from the 3‐km High‐Resolution Rapid Refresh (HRRR) model over offshore regions for the contiguous United States. The HRRR numerical weather prediction system runs once an hour and features hourly data assimilation, providing a key advantage over previous model‐based offshore wind datasets. On the basis of 1‐hour forecasts from the HRRR model, we highlight the different climatological regimes of the nearshore environment, characterizing the mean 80‐m wind speed as well as the frequency of exceeding 4, 12, and 25 m s?1 for east and west coast, Gulf of Mexico, and Great Lake locations. Preliminary verification against buoy measurements demonstrates good agreement with observations. This dataset can inform the placement of targeted measurement systems in support of improving resource assessments and wind forecasts to advance offshore wind energy goals both in New England and other coastal regions of the United States. 相似文献