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61.
Snarr Jeffery D.; Slep Amy M. Smith; Grande Vincent P. 《Canadian Metallurgical Quarterly》2009,21(3):390
Attributional theory and empirical evidence suggest that a tendency to make stable, global self-causal attributions for undesirable events is associated with negative outcomes. However, existing self-report measures of parental attributions do not account for the possibility that dysfunctional parent-causal attributions for child misbehavior might be important predictors of poor family functioning. To address these concerns, the authors developed and tested a new measure of both parent-causal and child-responsible attributions for child misbehavior in a sample of 453 community couples. Structural validity, convergent validity, discriminant validity, internal consistency, and temporal stability of the new measure were examined. As expected, confirmatory factor analysis resulted in 2 factors, Child-Responsible (9 items) and Parent-Causal (7 items); the final model was cross-validated in a holdout sample. The final scale demonstrated adequate internal consistency (αs = .81–.90), test–retest reliability (rs = .55–.76), and convergent and discriminant validity. Dysfunctional parent-causal and child-responsible attributions significantly predicted parental emotional problems, ineffective discipline, parent–child physical aggression, and low parenting satisfaction. Associations with parent–child aggression and parenting satisfaction were generally larger than with partner aggression and relationship satisfaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
A key notion in regenerative design is the co-evolutionary, partnered relationship between socio-cultural and ecological systems, which requires an explicit engagement with the implications and consequences of future design decisions. However, despite the extensive literature in other disciplines regarding the co-evolution of socio-cultural and ecological systems, this approach has yet to receive serious scrutiny within the context of the built environment and within the emerging notions of regenerative development and design. Drawing on an interdisciplinary body of literature, a discussion is initiated on how socio-cultural and ecological systems and their co-evolution might connect to the concept of regenerative design. Following a critique of a relevant example highlighting the current practice of regenerative design, the new building for the Centre for Interactive Research on Sustainability at the University of British Columbia, Vancouver, potentially relevant aspects of a socio-ecological system and of evolution theories are examined for the built environment. Several observations are presented on how these may offer a stronger theoretical framing of regenerative design, particularly the shifts in design thinking: from buildings as artefacts to their dynamic role in adaptive processes over time; widening the boundary focus of a building from its site to the neighbourhood. Une notion clé du design régénérateur est la relation coévolutionnaire de partenariat entre les systèmes socioculturels et écologiques, ce qui nécessite un engagement explicite à l'égard des implications et des conséquences des futures décisions en matière de design. Cependant, malgré la vaste littérature existant dans les autres disciplines concernant la coévolution des systèmes socioculturels et écologiques, cette approche doit encore faire l'objet d'un examen sérieux dans le contexte de l'environnement bâti et sous l'angle des notions émergentes de développement et de design régénérateurs. En s'appuyant sur un corpus interdisciplinaire de publications, une discussion est amorcée sur la manière dont les systèmes socioculturels et écologiques et leur coévolution pourraient être reliés au concept de design régénérateur. Après une critique portant sur un exemple pertinent mettant en évidence les pratiques actuelles du design régénérateur, le nouveau bâtiment du Centre de Recherche Interactive sur le Développement Durable de l'Université de Colombie Britannique, à Vancouver, sont examinés les aspects potentiellement pertinents d'un système socioécologique et des théories évolutionnistes, s'agissant de l'environnement bâti. Plusieurs observations sont présentées quant à la manière dont ceux-ci peuvent offrir un cadre théorique plus solide au design régénérateur, concernant en particulier les changements intervenant dans la façon de penser le design : des bâtiments envisagés en tant qu'artéfacts à leur rôle dynamique dans les processus adaptatifs au fil du temps, et un bâtiment dont les limites ne se focalisent plus sur son site, mais sont élargies à son quartier. Mots clés: environnement bâti, coévolution, cadres conceptuels, évolution, design régénérateur, systèmes socioécologiques 相似文献
63.
64.
Corrigendum: Mutating a Highly Conserved Residue in Diverse Cytochrome P450s Facilitates Diastereoselective Olefin Cyclopropanation 下载免费PDF全文
65.
66.
Danielle Quijano Amy L. Corcoran Edward L. Dreizin 《Propellants, Explosives, Pyrotechnics》2015,40(5):749-754
Mechanically alloyed Al ⋅ Mg powders with the mole fraction of Al varied from 0.47 to 0.9 were burned at atmospheric pressure in water vapor. The powders were carried by nitrogen through the center of a hydrogen‐oxygen diffusion flame. The particles ignited in the steam at approximately 2500 K, generated as the hydrogen‐oxygen flame product. Filtered photomultiplier tubes were used to capture the optical emission traces of individual particles as they burned. It was assumed that the measured durations of individual emission pulses are representative of individual particle burn times. Distributions of the burn times were obtained for each powder and correlated with respective particle size distributions to relate particle burn times with their sizes. Color temperatures corresponding to the particle emission signals were also obtained. It was observed that the burn times measured for alloys were more close to those of pure Al than Mg; for particles smaller than 2–3 μm, burn times for the alloys were shorter than for pure metal particles. The effect was strongest for the alloy with 50 wt‐% of Mg (Al0.47Mg0.54). Approximately, burn times, τ, as a function of particle size, d, could be estimated using a τ∼dn law, where n increased from 0.72 to 1.05 as the mole fraction of Mg increased from 0.1 to 0.53. The particle flame temperatures varied between 2500 and 3100 K for all alloys except for Al0.7Mg0.3, for which the temperatures were somewhat lower. The measured flame temperatures were reasonably close to the adiabatic flame temperatures calculated for combustion of mixed elemental Al and Mg in steam. 相似文献
67.
Payton Beeler Nicholas O. Jensen Soyoung Kim Amy Robichaux-Viehoever Bradley L. Schlaggar Deanna J. Greene Kevin J. Black Rajan K. Chakrabarty 《Journal of the Royal Society Interface》2022,19(187)
Tics manifest as brief, purposeless and unintentional movements or noises that, for many individuals, can be suppressed temporarily with effort. Previous work has hypothesized that the chaotic temporal nature of tics could possess an inherent fractality, that is, have neighbour-to-neighbour correlation at all levels of timescale. However, demonstrating this phenomenon has eluded researchers for more than two decades, primarily because of the challenges associated with estimating the scale-invariant, power law exponent—called the fractal dimension Df—from fractional Brownian noise. Here, we confirm this hypothesis and establish the fractality of tics by examining two tic time series datasets collected 6–12 months apart in children with tics, using random walk models and directional statistics. We find that Df is correlated with tic severity as measured by the YGTTS total tic score, and that Df is a sensitive parameter in examining the effect of several tic suppression conditions on the tic time series. Our findings pave the way for using the fractal nature of tics as a robust quantitative tool for estimating tic severity and treatment effectiveness, as well as a possible marker for differentiating typical from functional tics. 相似文献
68.
Richard A. Veazey Amy S. Gandy Derek C. Sinclair Julian S. Dean 《Journal of the American Ceramic Society》2020,103(4):2702-2714
Micro-contact impedance spectroscopy (MCIS) is potentially a powerful tool for the exploration of resistive surface layers on top of a conductive bulk or substrate material. MCIS employs micro-contacts in contrast to conventional IS where macroscopic electrodes are used. To extract the conductivity of each region accurately using MCIS requires the data to be corrected for geometry. Using finite element modeling on a system where the resistivity of the surface layer is at least a factor of ten greater than the bulk/substrate, we show how current flows through the two layers using two typical micro-contact configurations. This allows us to establish if and what is the most accurate and reliable method for extracting conductivity values for both regions. For a top circular micro-contact and a full bottom counter electrode, the surface layer conductivity (σs) can be accurately extracted using a spreading resistance equation if the thickness is ~10 times the micro-contact radius; however, bulk conductivity (σb) values can not be accurately determined. If the contact radius is 10 times the thickness of the resistive surface, a geometrical factor using the micro-contact area provides accurate σs values. In this case, a spreading resistance equation also provides a good approximation for σb. For two top circular micro-contacts on thin resistive surface layers, the MCIS response from the surface layer is independent of the contact separation; however, the bulk response is dependent on the contact separation and at small separations contact interference occurs. As a consequence, there is not a single ideal experimental setup that works; to obtain accurate σs and σb values the micro-contact radius, surface layer thickness and the contact separation must all be considered together. Here we provide scenarios where accurate σs and σb values can be obtained that highlight the importance of experimental design and where appropriate equations can be employed for thin and thick resistive surface layers. 相似文献
69.
Wilhelmina Kalt Shawna MacKinnon Jane McDonald Melinda Vinqvist Cheryl Craft Amy Howell 《Journal of the science of food and agriculture》2008,88(1):68-76
The concentrations and profiles of phenolics of selected fruit crops common in the Western diet, including several Vaccinium species, were examined to better understand how these crops may be useful sources of phenolic phytochemicals. Vaccinium fruit had a high phenolic concentration compared to non‐Vaccinium fruit. Some Vaccinium fruit were particularly rich in certain phenolic subgroups, especially anthocyanins and pro‐anthocyanidins. Among the pro‐anthocyanidin oligomers measured using fluorometric and mass spectroscopic detection, the trimers and tetramers were most abundant, while pro‐anthocyanidins with a degree of polymerization greater than 8 were least abundant. As biomedical studies determine which phenolic structures are associated with particular bioactivities, information on the phenolic concentration and profile of selected species will be useful in developing specific uses for fruit crops in human health. Methods were compared to assess the usefulness of simpler versus more sophisticated means of phenolic analysis. The phenolic components of fruit extracts were purified approximately 20‐fold, and not qualitatively altered, by C18 solid‐phase extraction. However, fruit extracts obtained from C18 solid‐phase extraction differed in their relative abundance of phenolic components. Colorimetric and HPLC‐DAD measures of phenolic concentration were correlated (R2 = 0.79), as was pro‐anthocyanidin concentration detected fluorometrically and by mass spectrometry (R2 = 0.44). Copyright © 2007 Crown in the right of Canada and Society of Chemical Industry 相似文献
70.
Michael S. Koch John M. DeSesso Amy Lavin Williams Suzanne Michalek Bruce Hammond 《Critical reviews in food science and nutrition》2016,56(3):512-526
To determine the reliability of food safety studies carried out in rodents with genetically modified (GM) crops, a Food Safety Study Reliability Tool (FSSRTool) was adapted from the European Centre for the Validation of Alternative Methods’ (ECVAM) ToxRTool. Reliability was defined as the inherent quality of the study with regard to use of standardized testing methodology, full documentation of experimental procedures and results, and the plausibility of the findings. Codex guidelines for GM crop safety evaluations indicate toxicology studies are not needed when comparability of the GM crop to its conventional counterpart has been demonstrated. This guidance notwithstanding, animal feeding studies have routinely been conducted with GM crops, but their conclusions on safety are not always consistent. To accurately evaluate potential risks from GM crops, risk assessors need clearly interpretable results from reliable studies. The development of the FSSRTool, which provides the user with a means of assessing the reliability of a toxicology study to inform risk assessment, is discussed. Its application to the body of literature on GM crop food safety studies demonstrates that reliable studies report no toxicologically relevant differences between rodents fed GM crops or their non-GM comparators. 相似文献