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1.
The production of the cognitive internal state word know by four 2- to 5-year-old children and their parents was examined. The levels of meaning of cognitive words can be categorized hierarchically along the dimensions of conceptual difficulty and abstractness (see Booth & Hall, 1995). The present study found that children and their parents expressed low levels of meaning less frequently, whereas they expressed high levels of meaning more frequently as a function of age. The children's use of know was also correlated positively with (1) their number of different words produced suggesting that cognitive words are related to more general semantic processes, and (2) with parental use of those same cognitive words suggesting that parental linguistic input may be an important mechanism in cognitive word acquisition. Finally, young children tended to use know more to refer to themselves than to refer to others, whereas their parents tended to use know equally to refer to self and others. The importance of cognitive words in a theory of language acquisition is discussed. 相似文献
2.
Complementing retrofit with engagement: exploring energy consumption with social housing tenants
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Cathrine V. Jansson‐Boyd Rosalyn A. V. Robison Ruth Cloherty Carlos Jimenez‐Bescos 《国际能源研究杂志》2017,41(8):1150-1163
Councils and social housing organisations are looking to retrofit as a way to make their housing more energy efficient. Previous studies on energy use in social housing have generally focussed on the technological aspects (such as the potential savings possible by retrofitting this class of housing across the UK) or have involved one‐off interventions or measures. During a 2‐year period, we worked with previously homeless people to reduce their energy consumption. The 32 participants lived in small blocks of flats (owned by a social housing organisation) that underwent retrofitting with air source heat pumps. We ran a three‐phase tenant engagement programme to compare a range of approaches aimed at energy reduction. It was found that education, social norms and self‐awareness are all key components when it comes to initiating environmentally responsible behaviours. The three approaches complemented each other, and these ought to be considered alongside technology provision if the aim is to reduce energy consumption. A number of reflections on the implementation of medium‐term tenant engagement programmes are also presented. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
3.
This article presents the fabrication and characterization of poly dimethylsiloxane/carbon nanofiber (CNF)-based nanocomposites. Although silica and carbon nanoparticles have been traditionally used to reinforce mechanical properties in PDMS matrix nanocomposites, this article focuses on understanding their impacts on electrical and thermal properties. By adjusting both the silica and CNF concentrations, 12 different nanocomposite formulations were studied, and the thermal and electrical properties of these materials were experimentally characterized. The developed nanocomposites were prepared using a solvent-assisted method providing uniform dispersion of the CNFs in the polymer matrix. Scanning electron microscopy was employed to determine the dispersion of the CNFs at different length scales. The thermal properties, such as thermal stability and thermal diffusivity, of the developed nanocomposites were studied using thermogravimetirc and laser flash techniques. Furthermore, the electrical volume conductivity of each type of nanocomposite was tested using the four-probe method to eliminate the effects of contact electrical resistance during measurement. Experimental results showed that both CNFs and silica were able to impact on the overall properties of the synthesized PDMS/CNF nanocomposites. The developed nanocomposites have the potential to be applied to the development of new load sensors in the future. 相似文献
4.
Effects of 24 to 48 h serum Ig concentration on growth and survival of 1000 Holstein heifer calves were evaluated. Average serum Ig for all calves was 25.71 (SD = 19.06) mg/ml with a range of .05 to 108.27. Serum Ig concentrations were below 12 mg/ml in 28% of the heifers. Both season and age of dam contributed significantly to the variation in 24 to 48 h concentrations of serum Ig. Concentration of serum Ig at 24 to 48 h was a significant source of variation affecting average daily gain through the first 180 d of life. Seasonal factors also were significant in influencing rate of gain from birth to 180 d. Age of dam was a significant source of variation in calf weight gains but only for the first 35 d. Mortality was 6.78% for heifers with less than 12 mg/ml serum Ig at 24 to 48 h as compared with 3.33% mortality for calves with greater than 12 mg/ml concentration. 相似文献
5.
Mariana‐Dana Damaceanu Irina Bacosca Maria Bruma Jenifer Robison Alexander Rusanov 《Polymer International》2009,58(9):1041-1050
BACKGROUND: Among the polymers widely studied for applications in advanced techniques, aromatic polyimides have received considerable attention due to their outstanding thermal stability associated with good electrical and mechanical properties. However, these polymers are usually difficult to process, being insoluble and without a glass transition. To improve the processing characteristics of polyimides, modification of their structure is often achieved by the introduction of flexible linkages in the macromolecular chain or various substituents on the aromatic rings. RESULTS: A series of polyimides and intermediate polyamidic acids were synthesized from aromatic oxadiazole‐diamines and a dianhydride containing a siloxane bridge (? R2Si? O? SiR2? ). These polymers exhibit good solubility in certain organic solvents and can be cast into thin and very thin films from their solutions. They exhibit high thermal stability with decomposition being above 440 °C and relatively low glass transition temperatures in the range 160–190 °C. These polymers show strong photoluminescence in the blue spectral region. CONCLUSION: The introduction of oxadiazole rings together with siloxane groups into the chains of aromatic polyimides gives highly thermostable polymers with remarkable solubility and film‐forming ability and that emit blue light, being attractive for applications in micro‐ and nanoelectronics and other related advanced fields. Copyright © 2009 Society of Chemical Industry 相似文献
6.
WG Robison JL Jacot JP Glover MD Basso TC Hohman 《Canadian Metallurgical Quarterly》1998,39(10):1933-1941
PURPOSE: To determine whether the diabetic-like thickening of retinal capillary basement membrane (RCBM) that develops in the galactose-fed rat model of diabetic ocular complications could be halted or ameliorated after 4 or 8 months of galactosemia by treatment with ARI-509, a potent new aldose reductase inhibitor (ARI), or by withdrawal of the galactose diet. METHODS: Weanling female Sprague-Dawley rats were randomized into eight groups and fed laboratory chow plus 50% starch, control group (CON); 50% D-galactose, galactose-fed group (GAL); 50% D-galactose with ARI-509 at 25 mg/kg or 10 mg/kg body wt per day, high-dose prevention group (HDP) and low-dose prevention group (LDP), respectively; 50% D-galactose for 4 or 8 months and then intervention by addition of ARI-509 (25 mg/kg body wt per day), 4-month intervention group (4IN) and 8-month intervention group (8IN), respectively; or 50% D-galactose for 4 or 8 months and then intervention by withdrawing galactose and replacing it with the 50% starch diet, 4-month galactose withdrawal group (4GW) and 8-month galactose withdrawal group (8GW), respectively. After 4, 8, 16, and 24 months of the experimental diets, the levels of carbohydrates in tissues and the extent of RCBM thickening in capillaries of the outer plexiform layer were determined in all groups. RESULTS: Retinal polyol was reduced by 95% in all ARI-treated groups and by 100% in the 4GW and 8GW groups after withdrawal of the galactose. The mean RCBM thickness increased rapidly in GAL rats, becoming almost two times greater (189 +/- 9.4 nm) than in CON rats (103 +/- 3.4 nm) by 24 months. Treatment with ARI-509 in high and low doses (HDP, LDP) initiated with the introduction of the galactose diet significantly prevented RCBM thickening at all time points (P < 0.05). In contrast, intervention by withdrawing galactose from the diet or by adding the high dose of ARI-509 had no significant effect (P < 0.05) on RCBM thickening until the 24-month time point (4IN, 166 +/- 10.3 nm; 8IN, 161 +/- 8.2 nm; 4GW, 136 +/- 5.1 nm; 8GW, 163 +/- 9.6 nm). CONCLUSIONS: Both early and late interventions decreased RCBM thickening compared with that in untreated GAL rats. The decreased thickening, however, was not evident until 16 to 20 months after the intervention. Because RCBM thickening is one of the earliest changes in diabetic and galactosemic retinopathy, the findings suggest that RCBM thickening and possibly subsequent retinal lesions are caused by early biochemical alterations induced by the galactose diet that are not readily reversed. The delayed response to therapy is consistent with that observed in the Diabetes Control and Complications Trial. The cumulative evidence indicates that intervention should begin as early after onset of diabetes as possible, and long follow-up periods should be used to evaluate efficacy. 相似文献
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9.
VA Robison DE Griffith JP Cegielski MR Reed DR Nash 《Canadian Metallurgical Quarterly》1998,94(10):48-52
The Center for Pulmonary and Infectious Disease Control (CPIDC), located on the campus of The University of Texas Health Center in Tyler, manages a toll-free infectious disease consultation hotline advertised to public and private physicians and to health care agencies throughout the state. From January 1994 through December 1996, as part of a statewide initiative to curb an unprecedented increase in the incidence of tuberculosis observed since 1985, a concentrated effort was made to solicit health care providers for consultation requests that involved the diagnosis and management of tuberculosis, in particular, drug-resistant varieties. During that period, 3447 calls were made to the CPIDC by 1682 physicians and nurses. While most of the calls originated from 4 major urban areas plus health care facilities along the border, calls were received from more than half of all the counties in Texas. The value of providing an infectious disease consultation service, readily available, without charge, to all members of the health care community is discussed. 相似文献
10.
WA Bleyer H Tejeda SB Murphy LL Robison JA Ross BH Pollock RK Severson OW Brawley MA Smith RS Ungerleider 《Canadian Metallurgical Quarterly》1997,21(6):366-373
PURPOSE: To determine whether adolescents with cancer, who in comparison to younger patients have a higher cancer incidence and lower mortality reduction, have equal access to national cancer clinical trials. METHODS: The ethnic/racial distribution of 29,859 subjects < 20 years of age entered onto National Cancer Institute-sponsored clinical trials between January 1, 1991, and June 30, 1994, was compared with the expected distribution of patients of the same age in the United States. RESULTS: The Children's Cancer Group and Pediatric Oncology Group had 29,134 (97.6%) of the total study entries among < 20-year-old subjects during the 3.5 years of surveillance. The adult cooperative groups accounted for < 3% of the clinical trials entries in the 15-19-year age range. When analyzed nationally by region, the under-representation of the older adolescent subjects was universal. From other analyses, the two pediatric cooperative groups were estimated to have registered > 94% of the children < 15 years of age who were expected to have been diagnosed to have cancer, but only 21% of the cancer patients in the 15-19-year age group. CONCLUSIONS: The national pediatric cancer cooperative groups allow the majority of American children < 15 years of age and their families equal opportunity to access clinical cancer trials, regardless of race or ethnicity. Among patients 15-19 years of age, however, > 75% are not being enrolled by any cooperative group sponsored by the National Cancer Institute. Thus, older adolescents are disadvantaged with respect to access to the national clinical trials, regardless of their race or ethnicity. 相似文献