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41.
Objective: The ability to select what is important to remember, to attend to this information, and to recall high-value items leads to the efficient use of memory. The present study examined how children with and without attention-deficit/hyperactivity disorder (ADHD) performed on an incentive-based selectivity task in which to-be-remembered items were worth different point values. Method: Participants were 6–9 year old children with ADHD (n = 57) and without ADHD (n = 59). Using a selectivity task, participants studied words paired with point values and were asked to maximize their score, which was the overall value of the items they recalled. This task allows for measures of memory capacity and the ability to selectively remember high-value items. Results: Although there were no significant between-groups differences in the number of words recalled (memory capacity), children with ADHD were less selective than children in the control group in terms of the value of the items they recalled (control of memory). All children recalled more high-value items than low-value items and showed some learning with task experience, but children with ADHD Combined type did not efficiently maximize memory performance (as measured by a selectivity index) relative to children with ADHD Inattentive type and healthy controls, who did not differ significantly from one another. Conclusions: Children with ADHD Combined type exhibit impairments in the strategic and efficient encoding and recall of high-value items. The findings have implications for theories of memory dysfunction in childhood ADHD and the key role of metacognition, cognitive control, and value-directed remembering when considering the strategic use of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Problem, research strategy, and findings: Local governments across the United States have for decades relied on the autocentric level of service (LOS) metric to analyze and impose exactions for the transportation impacts of land use developments. In California, LOS has dominated transportation impact analysis under the state’s project-level environmental review law. In that role, LOS has exacerbated the state’s notoriously tortuous development approval processes, particularly in urban areas. But LOS is on its way out. The state recently replaced LOS with vehicle miles traveled (VMT) as the primary measure—and basis for mitigation—of transportation impacts under the California Environmental Quality Act. Local governments must make the switch by July 1, 2020. We use a historical counterfactual approach to assess how replacing LOS with VMT could have affected the approval process for 153 land development projects over 16?years in the city of Los Angeles. We find that most projects could have benefited from at least some environmental review streamlining under the VMT-based framework recommended by the state, including more than 75% of residential-containing projects.

Takeaway for practice: Our results suggest that swapping LOS for VMT could reduce the environmental review burden for development in low-VMT urban areas and provide at least some of the approval process streamlining necessary to increase housing production in California. Similar impacts from an LOS-to-VMT switch could also potentially accrue outside of California under the right conditions, but more research is needed.  相似文献   

43.
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   
44.
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   
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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 τdn 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   
49.
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   
50.
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   
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