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71.
Tremblay R. E.; Masse B.; Perron D.; Leblanc M.; Schwartzman A. E.; Ledingham J. E. 《Canadian Metallurgical Quarterly》1992,60(1):64
Three alternative models concerning the causal links between early disruptive behavior, poor school achievement, and delinquent behavior or antisocial personality were tested with linear structural equation modeling. Ss were boys and girls followed from 1st grade to age 14 yrs. Disruptive behavior was assessed in Grade 1; school achievement was assessed in Grades 1 and 4; delinquent behavior and antisocial personality were assessed at age 14 yrs. With regard to self-reported delinquent behavior at age 14 yrs, results indicate that the best model for boys was a direct causal link between Grade 1 disruptive behavior and delinquent behavior. Poor school achievement was not a necessary causal factor. For girls, none of the tested models were a good fit to the delinquent behavior data. As for delinquent personality, results indicate that, for boys and girls, poor school achievement was a necessary component of the causal path between Grade 1 disruptive behavior and age 14 delinquent personality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Saturated solutions rerely form when the anhydrous constituents of aluminous and portland cement are stirred in water or in lime solutions of increasing concentrations. Apart from monocalcium aluminate, concentration of ions in solution cannot exceed maximum supersaturation with respect to the hydrate most likely to precipitate. The present work shows such a behavior for β-C2 S suspended in water and in lime solutions at low concentration. In more concentrated lime solutions, a short lifetime saturation state with respect to β-C2 S seems to be reached. 相似文献
73.
Mitchell Peter; Ropar Danielle; Ackroyd Katie; Rajendran Gnanathusharan 《Canadian Metallurgical Quarterly》2005,31(5):996
In 3 experiments the authors investigate how errors in perception produce errors in drawings. In Experiment 1, when Shepard stimuli were shown as a pair of tables, participants made severe errors in trying to adjust 1 part of the stimulus to match the other. When the table legs were removed, revealing a pair of parallelograms with minimal perspective cues, the illusion was weaker. The authors predicted that participants would err when drawing the table but not the parallelogram stimuli. The results of Experiment 2 support the prediction and establish a direct link between degree of perceptual distortion of the table stimuli and the severity of error in drawing. When drawing only the right-hand part of the figure, participants also erred to a greater degree in drawing the table than the parallelogram (Experiment 3). Collectively, the results suggest that perceptual distortion is linked with errors in drawing the table stimuli. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
74.
Traian V Chirila David A Morrison Zoya Gridneva Danielle Meyrick Celia R Hicks John M Webb 《Contact lens & anterior eye》2005,28(1):21-28
Drug-induced spoliation of hydrogels as contact lenses or as implants in the anterior eye is a frequent occurrence in clinical practice. This study explores the capacity of three commercial multipurpose solutions for contact lens care to reduce the spoliation of poly(2-hydroxyethyl methacrylate) (PHEMA) specimens exposed to a simulated aqueous humour formulation and to three topical drugs commonly administered after insertion of artificial corneas (Predsol, Optimol and Depo-Ralovera). ReNu MultiPlus (Bausch & Lomb), Complete Blink-N-Cleantrade mark Lens Drops (Allergan) and Complete Protein Remover Tablets dissolved in Complete ComfortPLUS (both from Allergan) were evaluated. All multipurpose solutions were able to dislodge passively the deposits formed on hydrogels in the simulated aqueous and in the presence of Predsol and Optimol, but none were effective against the deposits induced by Depo-Ralovera. A reduction of the calcium content in deposits caused by Predsol and Optimol was confirmed after treatment with the protein remover preparation, while the other multipurpose solutions caused the complete removal of the deposits. In experiments designed to evaluate the preventive action of the multipurpose solutions, no such effects were observed regardless of the drug involved. The prospect of using multipurpose solutions as eye drops following implantation of a hydrogel artificial cornea is a valid alternative for reducing device spoliation, however it appears to depend on the nature of the postoperative medication. 相似文献
75.
Quantitative Determination of Cellular Farnesyltransferase Activity: Towards Defining the Minimum Substrate Reactivity for Biologically Relevant Protein Farnesylation
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Susan C. Flynn Danielle E. Lindgren Prof. James L. Hougland 《Chembiochem : a European journal of chemical biology》2014,15(15):2205-2210
Prenylation is a post‐translational modification wherein an isoprenoid group is attached to a protein substrate by a protein prenyltransferase. Hundreds of peptide sequences are in vitro substrates for protein farnesyltransferase (FTase), but it remains unknown which of these sequences can successfully compete for in vivo prenylation. Translating in vitro studies to predict in vivo protein farnesylation requires determining the minimum reactivity needed for modification by FTase within the cell. Towards this goal, we developed a reporter protein series spanning several orders of magnitude in FTase reactivity as a calibrated sensor for endogenous FTase activity. Our approach provides a minimally invasive method to monitor changes in cellular FTase activity in response to environmental or genetic factors. Determining the reactivity “threshold” for in vivo prenylation will help define the prenylated proteome and identify prenylation‐dependent pathways for therapeutic targeting. 相似文献
76.
Optoelectronics: Flash‐Assisted Processing of Highly Conductive Zinc Oxide Electrodes from Water (Adv. Funct. Mater. 47/2015)
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77.
The individual response of saline lakes to a severe drought 总被引:1,自引:0,他引:1
Tweed S Grace M Leblanc M Cartwright I Smithyman D 《The Science of the total environment》2011,409(19):3919-3933
A severe protracted drought between 1997 and 2009 has altered the physical and chemical hydrology of a series of lakes in the Corangamite Basin of southeast Australia. Leading up to the drying out of most lakes (many for the first time on record), we document the changes in lakes' water quantity (water levels and inundation), salinity (Cl concentrations), salinity processes (Cl/Br ratios), nutrient concentrations and ratios (ammonia, phosphate and NOx (nitrate and nitrite)) and algae (as chlorophyll-a) for six lakes. All lakes show record declines in inundated areas and increases in salinity from pre-drought (< 1997) to drought conditions. However, the magnitude of change in salinity varies for different lakes, and there is no systematic change in the controls on lake salinity processes. Four lakes show no change in salinity processes, one lake shows the beginnings of change; where halite dissolution reactions increased closer to the time of the lake drying up, and another lake shows a marked shift from predominantly evaporation to the cyclic dissolution and precipitation of halite. Changes in filterable reactive phosphorus (FRP) values and lake N and P limitation predictions also showed little systematic correlation with changes in lake salinity, and nutrient values varied between lakes and over time. The decline in NOx concentrations in lakes where electrical conductivity (EC) values were above 100 mS/cm indicates some correlation with changes in salinity. Largely, these lakes exhibit individual changes in water quality parameters and salinity processes in response to the drought, indicating that while the stress of drought is regional, the hydrochemical response is local. In future changing climates, these results suggest that the catchment adaption strategies will require comprehensive plans for individual lake systems. 相似文献
78.
Schmitt Neal; Rogers William; Chan David; Sheppard Lori; Jennings Danielle 《Canadian Metallurgical Quarterly》1997,82(5):719
The effects of number of predictors, predictor intercorrelations, validity, and level of subgroup difference on composite validity, adverse impact ratios, and mean subgroup difference associated with various predictor composites, including and excluding a "high impact" ability measure, were assessed. The size of subgroup differences is substantially smaller when low-impact predictors are combined with a high-impact predictor, but hiring ratios for majority and minority groups still indicate a prima facie case of discrimination, using the fourth-fifths rule for most predictor-criterion combinations. However, the validity of a composite of alternate predictors and cognitive ability may exceed the validity of cognitive ability alone and reduce the size of subgroup differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
80.
Lehoux Josée; Guay Stéphane; Chartrand élise; Julien Danielle 《Canadian Metallurgical Quarterly》2007,39(4):307
Lack of social support (SS) is one of the most important factors influencing the development and maintenance of post-traumatic stress disorder (PTSD), and people living in couples seek the support of their spouse. To our knowledge, no study on PTSD has used an observational measure of SS in addition of the usual self-report method of measurement. The purpose of this study is to adapt the Social Support Interaction Global Coding System (SCIS) and to explore its psychometric properties using 20 support interactions videotaped with couples among whom a spouse has a PTSD diagnosis. Results suggest that the new SCIS (PTSD) shows satisfactory interrater reliability, good internal consistency and good convergent validity with self-reported measures of perceived support and marital adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献