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171.
Jacques Sophie; Zelazo Philip David; Kirkham Natasha Z.; Semcesen Tanya K. 《Canadian Metallurgical Quarterly》1999,35(3):770
In 2 experiments, an error-detection approach was used to determine whether 3-year-olds' perseverative errors on the postswitch phase of the Dimensional Change Card Sort (DCCS) are due to lack of response control or representational inflexibility. In Experiment 1, 3-, 4-, and 5-year-olds watched a puppet sort perseveratively on the postswitch phase and evaluated its responses. Most 4- and 5-year-olds detected the puppet's perseverative errors, whereas most 3-year-olds failed to do so despite detecting errors on a simpler card sort. Experiment 2 revealed that 3-year-olds who failed to correctly evaluate the puppet's behavior tended to fail their own DCCS. Results imply that perseveration on the DCCS cannot be attributed to difficulty inhibiting prepotent motor responses. Instead, changes in rule use between 3 and 5 years of age are interpreted in terms of the development of representational flexibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
172.
Dollard Maureen F.; LaMontagne Anthony D.; Caulfield Natasha; Blewett Verna; Shaw Andrea 《Canadian Metallurgical Quarterly》2007,14(4):417
We reviewed 25 international and 10 Australian studies published between 1999 and 2004 for evidence of individual and organizational impacts of stress in the health and community services (HCS) sector. Several HCS occupations showed high levels of distress compared to Australian population data. Results were consistent with the Job Demands-Resources model: High demands (e.g., workload, emotional) combined with low resources (e.g., control, rewards, support) were associated with adverse health (e.g., psychological, physical) and organizational impacts (e.g., reduced job satisfaction, sickness absence). Australian-specific issues included rural and remote work and the complex role of Aboriginal Health Workers. Strong associations between modifiable work factors and adverse outcomes provide a rationale for primary preventive policy development by occupational health and safety regulators and workers' compensation authorities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
173.
Caulfield Natasha; Chang David; Dollard Maureen F.; Elshaug Carol 《Canadian Metallurgical Quarterly》2004,11(2):149
The authors investigated empirical research into occupational stress interventions conducted in Australia within the past 10 years. They focused on evidence published and the quality of the evidence base. All intervention studies were conducted in the public sector. Only 1 study reached the gold standard in evidence-based research. Most interventions were individually focused, despite the preponderance of research identifying risky work environment stressors. Results suggest a paucity of published information regarding what works with occupational stress interventions in Australia and an urgent need for further research in the area, particularly focusing on the private sector, rural workers, and scientific evaluation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
174.
Penny J. Walsh Natasha J. Lundin Keith C. Gordon Ji-Young Kim Chang-Hee Lee 《Optical Materials》2009,31(10):1525
A series of functionalized dipyrido[3,2-a:2′,3′-c]phenazine complexes with copper(I), rhenium(I), ruthenium(II) and iridium(III) have been synthesized and used as dopants in OLEDs. The ruthenium-based complexes are the most efficient appearing blue in colour, the copper complexes give devices that appear white in emission. In most cases the emission colour is a mixture of emission from the metal complex and from the matrix (PVK). 相似文献
175.
Mahshid Nikpour Nezhati Gholam Hossein Riazi Homayon Ahmad Panahi Elham Moniri Nasir Ahmad Rajabi Mohammad Mehdi Sadughi Natasha Rahmani Zaker Robab Ardekani Reihaneh Kooshkestani 《Korean Journal of Chemical Engineering》2013,30(3):675-679
The sodium salt of di ((1-hydroxy-2-benzothiazolium-1-yl) ethyliden-1,1-H-bisphosphonic acid) orthophosphate was synthesized and its toxicity and viability effects screened on two different human neuroblastoma cell lines. This novel derivative of benzothiazole provides a new compound in connection with research and therapeutic application for tumor cell growth inhibition. Benzothiazole was alkylated in reaction with bromoacetic acid and then converted to its H-bisphosphonic acid derivative in presence of H3PO3/POCl3. The procedure led to formation of two molecules of corresponding H-bisphosphonic acid which attached together via a phosphate bridge. The investigated compound exhibits activities (IC50 value) ranging from 14–23 μM (corresponding to human neuroblastoma SK-BE (2) and SK-NM-C cells). 相似文献
176.
Natasha Shirshova Angelika Menner Gary P. Funkhouser Alexander Bismarck 《Cement and Concrete Research》2011,(4):443-450
We polymerised the continuous styrene/divinylbenzene monomer phase of high internal phase emulsions (HIPEs) containing 70 vol.% cement slurry as internal phase to synthesise polymer cement hybrid materials. These novel cement containing poly(merised)HIPEs have an interconnected bi-phasic structure consisting of an interpenetrating network of set cement and polymer. Incorporating 14 wt.% of polymer into the cement resulted in an increased compressive strain to failure as compared to pure set cement but both elastic modulus and crush strength decreased. These novel polymer cement hybrid materials have a better chemical resistance against acetic acid then pure cement and showed also no shrinkage when exposed to xylene and dodecane. 相似文献
177.
178.
An introduction to the special issue on the multilevel measurement model (MMM) is provided. The two- and three-level multilevel models for continuous outcomes are reviewed. The extension to the hierarchical generalized linear model and its use as a multilevel measurement model for dichotomous measurement indicators is demonstrated. The six articles in the special issue are described. 相似文献
179.
The blood concentration of 1,8-cineole and its metabolites was measured in six male brushtail possums while they voluntarily
fed on diets laced with varying concentrations of cineole for 3 d. On the third day, blood samples were collected during and
after each bout of feeding for 3 hr. Blood cineole was measured by using headspace solid-phase microextraction (SPME), while
cineole metabolites were measured by liquid–liquid extraction followed by gas chromatography-mass spectroscopy. Feeding patterns
were measured by continual recording of residual food weight and time. Cineole absorption was rapid, resulting in a peak blood
concentration at the end of each feeding bout. The blood concentration of cineole did not exceed a critical value (51.8 ±
14.1 μmol/l) regardless of the concentration in the diet. Food and, therefore, cineole intake was regulated. The amount of
food ingested in the first feeding bout decreased from 236 ± 52 g on the control diet to 36 ± 20 g on the 4% cineole diet.
The amount of cineole ingested in the first bout (1.18 ± 1.10 g) was the same regardless of the dietary concentration and
was controlled by the size of the meal. Total food eaten during the 7-hr feeding session decreased by 64% from 368 ± 94 g
(control diet) to 131 ± 52 g (4% diet). Total cineole intake increased from 2.47 ± 0.60 g (1% diet) to 5.05 ± 2.41 g (4% diet).
Cineole metabolites accumulated throughout the sampling period and were generally still rising at the end of blood sampling
period. Blood levels of metabolites were at least 10-fold higher than cineole levels. The immediate control of feeding seems
to be regulated by blood levels of cineole, whereas metabolites are likely to be more important in regulating the chronic
ingestion of cineole. 相似文献
180.
Landell-Mills N 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2002,360(1797):1817-1825
Market-based approaches to environmental management are all the rage. Claims that market mechanisms can encourage environmental protection and promote greater economic efficiency while saving taxpayers' money are tantalizing. In the forestry sector, policy makers are widely heeding this advice and shrinking command-and-control systems in favour of incentive mechanisms that seek to align private enthusiasm with the public good. In some cases, governments are even promoting the creation of markets where none existed before. In others, markets are evolving of their own accord. In such times of change, it is difficult to stand back and take stock. Yet, it is during such times that guidance is most needed. In the rush to introduce market-based solutions to environmental problems, a particular concern is how markets are impacting on the poor. In this paper an effort is made to draw on a recent review of markets for four forest environmental services (biodiversity conservation, carbon sequestration, watershed protection and landscape beauty) to draw out preliminary insights into how markets are performing with respect to their impacts on the poor. The evidence suggests a need for caution. While the potential benefits are significant, the poor face an uphill battle in realizing them. Key constraints facing the poor include a lack of property rights over forest resources and their environmental services; inadequate skills and education; poor market information; lack of market contacts; inadequate communication infrastructure; inappropriate contract design; and lack of access to financial resources. To tackle these, four potential ways forward are highlighted: (1) assign property rights to forest assets and their related environmental services in ways that respect customary arrangements and poor people's tenure; (2) strengthen capacity for market participation, e.g. through training and education; (3) invest in the provision of market information, advice and, essentially, a contact point for buyers and sellers, perhaps through the establishment of a 'market support centre'; and (4) improve access to finance so that poor individuals can make necessary up-front investments in market participation. 相似文献