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981.
Schwanenflugel Paula J.; Henderson Robbie L.; Fabricius William V. 《Canadian Metallurgical Quarterly》1998,34(5):850
Reports an error in "Developing organization of mental verbs and theory of mind in middle childhood: Evidence from extensions" by Paula J. Schwanenflugel, Robbie L. Henderson and William V. Fabricius (Developmental Psychology, 1998[May], Vol 34[3], 512-524). In this article, Figures 2 and 4 were inadvertently switched. The figure appearing on page 519 is Figure 4, and the data pertain to third graders; the figure appearing on page 521 is Figure 2, and the data pertain to adults. (The following abstract of the original article appeared in record 1998-01885-012.) The purpose of the study was to assess developments in the theory of mind suggested by changes in the organization of cognitive verb extensions during the elementary school years. Adults and 3rd- and 5th-grade children were provided with a set of mental activity scenarios and were asked to select the best verbs from a list of cognitive verbs that might apply to each scenario. Changes in organization were assessed by examining overlapping uses of cognitive verbs in different contexts. There were 3 major changes with development: (a) the understanding of the role of memory in input functions increased, (b) the interrelatedness of memory- and comprehension-related verbs increased, and (c) the importance of cognitive certainty and uncertainty engaged by constructive processing verbs increased. Together, these findings suggest that a constructivist theory of mind develops in later childhood. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
982.
The soil microbial biomass quotient (expressed as a percentage of the total soil organic carbon) and the specific rate of carbon-dioxide production by soil microbes (respiration quotient) are often used as indicators of stress on soil microbial populations. A low biomass quotient or a high respiration quotient is considered to be an indication of stress from, for example, toxicity from metals in sewage sludge applied to soils. These metabolic quotients are affected by a wide variety of other factors such as the biodegradability of soil organic-carbon amendments, plant inputs of organic carbon into soils, natural variations in microbial population sizes with depth, and in the rhizosphere of plants. These variations could be sufficiently large to make interpretation of changes in biomass quotient and respiration quotient, as a response to stress, problematical. 相似文献
983.
Míguez-Framil M Moreda-Piñeiro A Bermejo-Barrera P López P Tabernero MJ Bermejo AM 《Analytical chemistry》2007,79(22):8564-8570
The use of ultrasound energy for accelerating the pronase E enzymatic hydrolysis of human hair for extracting illicit drugs has been novelty tested. The enzymatic extracts obtained after 30 min of sonication in an ultrasonic water bath were subjected to an optimized solid-phase extraction process, which involved a solution of 2.0% (v/v) acetic acid in methanol as eluting solution and concentration by N2 stream evaporation. A gas chromatography/mass spectrometry method was used to separate and determine cocaine, benzoylecgonine, codeine, morphine, and 6-monoacethylmorphine in 20 min. Variables affecting ultrasound-assisted pronase E hydrolysis such as hydrolysis temperature, hydrolysis time, enzyme concentration, catalyzer (1,4-dithiothreitol) concentration, ionic strength, pH, and ultrasound frequency were simultaneously evaluated by a Plackett-Burman design 2(8) PBD of resolution III. The most statistically significant variables were ionic strength and pH, which means that analyte extraction is mainly attributed to pronase E activity. The optimization or evaluation of all the factors has led to an accelerated pronase E hydrolysis of human hair, which can be completed in 30 min. Results have been found to be statistically similar to those obtained with conventional pronase E hydrolysis. The accelerated method was finally applied to several human hair samples from multidrug abusers. 相似文献
984.
Ricard Fogues Jose M. Such Agustin Espinosa Ana Garcia-Fornes 《International journal of human-computer interaction》2013,29(5):350-370
Social networking services (SNSs) such as Facebook and Twitter have experienced explosive growth during the few past years. Millions of users have created their profiles on these services because they experience great benefits in terms of friendship. SNSs can help people to maintain their friendships, organize their social lives, start new friendships, and meet others who share their hobbies and interests. However, all these benefits can be eclipsed by the privacy hazards that affect people in SNSs. People expose intimate information about their lives on SNSs, and this information affects the way others think about them. It is crucial that users be able to control how their information is distributed through the SNSs and decide who can access it. This article presents a list of privacy threats that can affect SNS users and what requirements privacy mechanisms should fulfill to prevent this threats. Then the article reviews current approaches and analyzes to what extent they cover the requirements. 相似文献
985.
Harvey Elizabeth A.; Youngwirth Sara D.; Thakar Dhara A.; Errazuriz Paula A. 《Canadian Metallurgical Quarterly》2009,77(2):349
The present study examined the power of measures of early preschool behavior to predict later diagnoses of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD)/conduct disorder (CD). Participants were 168 children with behavior problems at age 3 who underwent a multimethod assessment of ADHD and ODD symptoms and were followed annually for 3 years. Fifty-eight percent of 3-year-old children with behavior problems met criteria for ADHD and/or ODD/CD 3 years later. Using a diagnostic interview and rating scales at age 3, the authors could accurately predict later diagnostic status for 3/4 of children for ADHD and for 2/3 of children for ODD/CD. Predictive power of the best models did not increase significantly at age 4 and age 5 compared with age 3. Results provide support for the validity of early diagnoses of ADHD, although caution is needed in making diagnoses because a significant minority of children with early hyperactivity and inattention do outgrow their problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
986.
Fichorova RN Richardson-Harman N Alfano M Belec L Carbonneil C Chen S Cosentino L Curtis K Dezzutti CS Donoval B Doncel GF Donaghay M Grivel JC Guzman E Hayes M Herold B Hillier S Lackman-Smith C Landay A Margolis L Mayer KH Pasicznyk JM Pallansch-Cokonis M Poli G Reichelderfer P Roberts P Rodriguez I Saidi H Sassi RR Shattock R Cummins JE 《Analytical chemistry》2008,80(12):4741-4751
The increase of proinflammatory cytokines in vaginal secretions may serve as a surrogate marker of unwanted inflammatory reaction to microbicide products topically applied for the prevention of sexually transmitted diseases, including HIV-1. Interleukin (IL)-1beta and IL-6 have been proposed as indicators of inflammation and increased risk of HIV-1 transmission; however, the lack of information regarding detection platforms optimal for vaginal fluids and interlaboratory variation limit their use for microbicide evaluation and other clinical applications. This study examines fluid matrix variants relevant to vaginal sampling techniques and proposes a model for interlaboratory comparisons across current cytokine detection technologies. IL-1beta and IL-6 standards were measured by 12 laboratories in four countries, using 14 immunoassays and four detection platforms based on absorbance, chemiluminescence, electrochemiluminescence, and fluorescence. International reference preparations of cytokines with defined biological activity were spiked into (1) a defined medium simulating the composition of human vaginal fluid at pH 4.5 and 7.2, (2) physiologic salt solutions (phosphate-buffered saline and saline) commonly used for vaginal lavage sampling in clinical studies of cytokines, and (3) human blood serum. Assays were assessed for reproducibility, linearity, accuracy, and significantly detectable fold difference in cytokine level. Factors with significant impact on cytokine recovery were determined by Kruskal-Wallis analysis of variance with Dunn's multiple comparison test and multiple regression models. All assays showed acceptable intra-assay reproducibility; however, most were associated with significant interlaboratory variation. The smallest reliably detectable cytokine differences ( P < 0.05) derived from pooled interlaboratory data varied from 1.5- to 26-fold depending on assay, cytokine, and matrix type. IL-6 but not IL-1beta determinations were lower in both saline and phosphate-buffered saline as compared to vaginal fluid matrix, with no significant effect of pH. The (electro)chemiluminescence-based assays were most discriminative and consistently detected <2-fold differences within each matrix type. The Luminex-based assays were less discriminative with lower reproducibility between laboratories. These results suggest the need for uniform vaginal sampling techniques and a better understanding of immunoassay platform differences and cross-validation before the biological significance of cytokine variations can be validated in clinical trials. This investigation provides the first standardized analytic approach for assessing differences in mucosal cytokine levels and may improve strategies for monitoring immune responses at the vaginal mucosal interface. 相似文献
987.
988.
Yusong Wang Ana Belén Serrano Kadir Sentosun Sara Bals Luis M. Liz‐Marzán 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(34):4314-4320
Surface chemistry plays a pivotal role in regulating the morphology of nanoparticles, maintaining colloidal stability, and mediating the interaction with target analytes toward practical applications such as surface‐enhanced Raman scattering (SERS)‐based sensing and imaging. The use of a binary ligand mixture composed of 1,4‐benzenedithiol (BDT) and hexadecyltrimethylammonium chloride (CTAC) to provide gold nanostars with long‐term stability is reported. This is despite BDT being a bifunctional ligand, which usually leads to bridging and loss of colloidal stability. It is found however that neither BDT nor CTAC alone are able to provide sufficient colloidal and chemical stability. BDT‐coated Au nanostars are additionally used as seeds to direct the encapsulation with a gold outer shell, leading to the formation of unusual nanostructures including semishell‐coated gold nanostars, which are characterized by high‐resolution electron microscopy and electron tomography. Finally, BDT is exploited as a probe to reveal the enhanced local electric fields in the different nanostructures, showing that the semishell configuration provides significantly high SERS signals as compared to other core–shell configurations obtained during seeded growth, including full shells. 相似文献
989.
José Vicente Calvano Antônio Carneiro de Mesquita Filho Vladimir Castro Alves Marcelo Soares Lubaszewski 《Microelectronics Journal》2002,33(10):823-834
This work presents a method for synthesizing testable continuous-time linear time-invariant electrical networks using 1st order blocks for the implementation of analog linear circuits. A functional-structural fault model for the block, and a fault dictionary are proposed together with a simple set of test vectors. The method allows, also, the fault grade evaluation for the modeled faults. The results obtained from the two application examples have shown the suitability of the approach as a design for test method for analog circuits. 相似文献
990.
Ana E. Bianchi Tomás S. Plivelic Graciela Punte Iris L. Torriani 《Journal of Materials Science》2008,43(10):3704-3712
The microstructural properties of polycrystalline CuO powders and their evolution during controlled high energetic ball milling
(HEBM) were studied using conventional X-ray diffraction (XRD) techniques and in situ temperature-dependent small and wide
angle scattering (SAXS–WAXS) synchrotron radiation experiments. Volume weighted average grain size, unit cell expansion, oxygen
deficiency, and microstrain values as a function of milling time were obtained from XRD. SAXS data revealed different nanostructures
for samples synthesized by one-step solid-state reaction (SSR) or HEBM-treated powders. The latter presented the characteristics
of a multilayered nanoscale solid system with surface fractal behavior. Correlation of the XRD microstructural parameters
and the power law exponent of the SAXS curves as a function of temperature and milling time provided a coherent picture of
the structure of HEBM-treated powders. The overall structural information presented in this article may shed some light on
the macroscopic physical properties of CuO nanostructures. 相似文献