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31.
The present investigation employed an alternating treatments design to (1) examine the efficacy of group contingencies in the reduction of disruptive behavior, and (2) compare the effects of independent, interdependent, and dependent group contingencies in the reduction of disruptive behavior in adolescent males identified with serious emotional disturbance. Disruptive classroom behavior has been associated with both decrement inacademic performance and increased risk for antisocial behavior. Although research findings have suggested that group contingencies are efficacious in reducing disruptive behavior, the data remain inconclusive regarding which group contingency (interdependent, dependent, and independent) is most effective. Results suggest that a clear superiority among the group contingencies was not evidenced. However, all were dramatically effective in the reduction of classroom disruptive behavior. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
32.
Despite the dangers associated with drink walking, limited research is currently available regarding the factors which influence individuals to engage in this risky behaviour. This study examined the influence of psychosocial factors upon individuals’ intentions to drink walk across four experimental scenarios (and a control condition). Specifically, a 2 × 2 repeated measures design was utilised in which all of the scenarios incorporated a risky pedestrian crossing situation (i.e., a pedestrian crossing against a red man signal) but differed according to the level of group identity (i.e., low/strangers and high/friends) and conformity (low and high). Individuals were assessed for their intentions to drink walk within each of these different scenarios. Undergraduate students (N = 151), aged 17–30 years, completed a questionnaire. Overall, most of the study's hypotheses were supported with individuals reporting the highest intentions to drink walk when in the presence of friends (i.e., high group identity) and their friends were said to be also crossing against the red man signal (i.e., high conformity). The findings may have significant implications for the design of countermeasures to reduce drink walking. For instance, the current findings would suggest that potentially effective strategies may be to promote resilience to peer influence as well as highlight the negative consequences associated with following the behaviour of other intoxicated pedestrians who are crossing against a red signal.  相似文献   
33.
Hybrid PET/MRI scanners have the potential to provide fundamental molecular, cellular, and anatomic information essential for optimizing therapeutic and surgical interventions. However, their full utilization is currently limited by the lack of truly multi‐modal contrast agents capable of exploiting the strengths of each modality. Here, we report on the development of long‐circulating positron‐emitting magnetic nanoconstructs (PEM) designed to image solid tumors for combined PET/MRI. PEMs are synthesized by a modified nano‐precipitation method mixing poly(lactic‐co‐glycolic acid) (PLGA), lipids, and polyethylene glycol (PEG) chains with 5 nm iron oxide nanoparticles (USPIOs). PEM lipids are coupled with 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid (DOTA) and subsequently chelated to 64Cu. PEMs show a diameter of 140 ± 7 nm and a transversal relaxivity r2 of 265.0 ± 10.0 (mM × s)?1, with a r2/r1 ratio of 123. Using a murine xenograft model bearing human breast cancer cell line (MDA‐MB‐231), intravenously administered PEMs progressively accumulate in tumors reaching a maximum of 3.5 ± 0.25% ID/g tumor at 20 h post‐injection. Correlation of PET and MRI signals revealed non‐uniform intratumoral distribution of PEMs with focal areas of accumulation at the tumor periphery. These long‐circulating PEMs with high transversal relaxivity and tumor accumulation may allow for detailed interrogation over multiple scales in a clinically relevant setting.  相似文献   
34.
Generating sentences from a library of signs implemented through a sparse set of key frames derived from the segmental structure of a phonetic model of ASL has the advantage of flexibility and efficiency, but lacks the lifelike detail of motion capture. These difficulties are compounded when faced with real-time generation and display. This paper describes a technique for automatically adding realism without the expense of manually animating the requisite detail. The new technique layers transparently over and modifies the primary motions dictated by the segmental model and does so with very little computational cost, enabling real-time production and display. The paper also discusses avatar optimizations that can lower the rendering overhead in real-time displays.  相似文献   
35.
The purpose of the present study is to identify the potential contribution that a firm's climate supporting creativity can make towards understanding the effective implementation of novel marketing programmes. Specifically, a conceptual model is developed and empirically tested with Bayesian path analysis, using data obtained from managers of 87 Greek firms. Results suggest that a firm's climate that supports creativity has an indirect effect on marketing programme implementation effectiveness through marketing programme novelty. Additionally, climate for creativity moderates the relationship between marketing programme novelty and marketing programme implementation effectiveness such that the indirect effect of climate for creativity on marketing programme implementation effectiveness was found significant for levels of climate moderate to low, but not when the level of climate for creativity was high. Recommendations for further research are discussed.  相似文献   
36.
37.
Tumor-specific metabolic adaptations offer an interesting therapeutic opportunity to selectively destroy cancer cells. However, solid tumors also present gradients of nutrients and waste products across the tumor mass, forcing tumor cells to adapt their metabolism depending on nutrient availability in the surrounding microenvironment. Thus, solid tumors display a heterogenous metabolic phenotype across the tumor mass, which complicates the design of effective therapies that target all the tumor populations present. In this work, we used a microfluidic device to study tumor metabolic vulnerability to several metabolic inhibitors. The microdevice included a central chamber to culture tumor cells in a three-dimensional (3D) matrix, and a lumen in one of the chamber flanks. This design created an asymmetric nutrient distribution across the central chamber, generating gradients of cell viability. The results revealed that tumor cells located in a nutrient-enriched environment showed low to no sensitivity to metabolic inhibitors targeting glycolysis, fatty acid oxidation, or oxidative phosphorylation. Conversely, when cell density inside of the model was increased, compromising nutrient supply, the addition of these metabolic inhibitors disrupted cellular redox balance and led to tumor cell death.  相似文献   
38.
Recently, (Ga1-xZnx)(N1-xOx) has gained widespread attention as a comparatively high efficiency photocatalyst for visible-light-driven overall water splitting. Despite significant gains in efficiency over the past several years, a majority of the photogenerated carriers recombine within bulk powders. To improve the photocatalytic activity, we used an epitaxial casting method to synthesize single-crystalline, high surface area (Ga1-xZnx)(N1-xOx) nanotubes with ZnO compositions up to x=0.10. Individual nanotubes showed improved homogeneity over powder samples due to a well defined epitaxial interface for ZnO diffusion into GaN. Absorption measurements showed that the ZnO incorporation shifts the absorption into the visible region with a tail out to 500 nm. Gas chromatography (GC) was used to compare the solar water splitting activity of (Ga1-xZnx)(N1-xOx) nanotubes (x=0.05–0.10) with similar composition powders. Cocatalyst decorated samples were dispersed in aqueous solutions of CH3OH and AgO2CCH3 to monitor the H+ reduction and H2O oxidation half reactions, respectively. The nanotubes were found to have approximately 1.5–2 times higher photocatalytic activity than similar composition powders for the rate limiting H+ reduction half reaction. These results demonstrate that improvements in homogeneity and surface area using the nanotube geometry can enhance the photocatalytic activity of GaN:ZnO for solar water splitting.  相似文献   
39.
The remote West Australian town of Broome has a unique photography heritage that sheds new light on the complexities of photography and intercultural relations. During the early twentieth century thriving Japanese communities were established in this region around the lucrative pearling industry. These Japanese communities also helped to develop a fascinating photography culture in Broome. Photography was not simply a business opportunity for the Japanese or a means of documenting people and events; it was a medium through which hierarchised social relations were produced, redefined, and challenged. This article examines photographs by these Japanese residents as an important site of cross-cultural communication and interpretation. These photographs of Anglo-Australian, Japanese, and Aboriginal residents of Broome enrich the study of cross-cultural photographic encounters, and emphasise the dynamic and dispersed qualities of Australian photographic practice and history. Here national histories of photography are usefully conceptualised as the products of imbricated social, economic, and cultural relations that operate across regional, national, and international realms.  相似文献   
40.

Electricity consumption is influenced by number of adults and children and their relationship at household level. Household income also plays a critical role on expenditure on electricity. Accordingly, this article presents a joint probability model of electricity demand based on occupants’ age grades and household income levels. A bottom-up strategy is developed using a micro level database of 70 Australian households. A neural regression-generalization technique is devised to estimate electricity demand using back-propagation and cognitive mapping. The aggregated result is then validated against 2012 Australian national census. Accordingly, the model is improved based on a top-down review. The results show per capita electricity demand by adult and child at 0.408 kW (69 kWh/week) and 0.226 kW (38 kWh/week), respectively. The equivalent dollar values are $13.6/week and $7.6/week in 2012. At macro level, the model reveals per capita demand by all individuals at 0.324 kW (54.35 kWh/week) equivalent to dollar value of $10.87/week, across Australia. The results also show higher percentage of per capita demand for adults in high and medium income classes, and the otherwise for low income class. Ratio of child’s demand over adult’s demand is highest among the low income households, and lowset among the middle income households, while best balance between adult and child per capita demand belongs to the high income.

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