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排序方式: 共有909条查询结果,搜索用时 31 毫秒
91.
This study compared the sensitivity and teaching strategies of dysphoric and nondysphoric women working with unfamiliar 5- and 6-year-olds. Interactions of 20 dysphoric and 20 nondysphoric mothers and an unfamiliar child were observed during 2 classification tasks and 3 unstructured activities staged as breaks. Nondysphoric women were more sensitive to children's level of understanding than dysphoric women and were more likely to use a variety of teaching strategies. Dyads with nondysphoric women were also more likely to share decision making than dyads with dysphoric women. These differences between dysphoric and nondysphoric women were significant only in the structured classification tasks. The findings indicate that in some situations dysphoric and nondysphoric women vary in their sensitivity to children's cues and in the teaching strategies they use with children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Definitions of business process given in much of the literature on Business Process Management are limited in depth and their related models of business processes are correspondingly constrained. After giving a brief history of the progress of business process modeling techniques from production systems to the office environment, this paper proposes that most definitions are based on machine metaphor type explorations of a process. While these techniques are often rich and illuminating it is suggested that they are too limited to express the true nature of business processes that need to develop and adapt to today's challenging environment. 相似文献
93.
Morelli Gilda A.; Rogoff Barbara; Oppenheim David; Goldsmith Denise 《Canadian Metallurgical Quarterly》1992,28(4):604
Examines the decisions of middle-class US and Highland Mayan parents regarding sleeping arrangements during their child's 1st 2 yrs and their explanations for their differing practices. All 14 Mayan children slept in their mothers' beds into toddlerhood. None of the 18 US infants slept in bed with their mothers on a regular basis as newborns, although 15 slept near their mothers until age 3–6 mo, when most were moved to a separate room. The Mayan parents explained their practices in terms of the value of closeness with infants; US parents explained their practices in terms of the value of independence for infants. US families, but not Mayan families, used bedtime routines and objects to facilitate the transition to sleep. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
McAweeney Mary J.; Forchheimer Martin; Tate Denise G. 《Canadian Metallurgical Quarterly》1997,42(2):125
Reviews the value of null statistical hypothesis testing and discuss its limitations and misuses. It is contended that this method is of nominal utility in outcomes research, that rehabilitation researchers should focus on the calculation and interpretation of statistical power and effect size. During this era when outcomes are paramount, researchers in rehabilitation psychology cannot afford to conduct studies where significant methodological shortcomings compromise the validity of the results. Study design, evaluation, and presentation recommendations for the appropriate use and interpretation of statistical analysis in outcomes research are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Study of the modulus of elasticity of polymer concrete compounds and comparative assessment of polymer concrete and portland cement concrete 总被引:1,自引:0,他引:1
The main aim of this study is to assess the modulus of elasticity of polymer concrete (PC) compounds produced using two types of binders: orthophtalic or isophtalic polyester. The compositions used were selected from a previous study that identified cost-effective PC compositions. Based on those data, the concentrations of polymer used were 12% of orthophtalic polyester and 13% of isophtalic polyester by weight of the dry materials. Fly ash was used as a filler and compositions with 8%, 12%, 16% and 20% of ash by weight of aggregate were studied. Results indicate that all compositions assessed in this study display high modulus of elasticity values. Statistical analysis of the data reveals that the type of resin and the concentration of fly ash, both in isolation and in combination, have a significant effect on the modulus of elasticity of these compounds. 相似文献
96.
Zelazo Philip David; Reznick J. Steven; Pi?on Denise E. 《Canadian Metallurgical Quarterly》1995,31(3):508
Two-year-olds' difficulty with rule execution is robust and pervasive. In Experiment 1, 120 32-month-olds received 1 of 6 tasks: a task assessing knowledge about a series of items; a deductive card sort requiring children to use their knowledge to sort the items by rules; and 4 modifications of the card sort that provided various types of task support. Children performed better on the knowledge task than the other tasks, which did not differ. Errors increased over trials and were typically perseverative. Experiment 2 replicated the finding that children failed to use rules systematically even when items were labeled by the rules' antecedents. Improvements in rule use seem to reflect emerging control over actions rather than increased representational flexibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Denise C. Hunter Jingli Zhang Lesley M. Stevenson Margot A. Skinner 《International Journal of Food Science & Technology》2008,43(12):2123-2129
Developing functional food products requires a structured approach for screening potential ingredients. Using the development of a product with antioxidant properties as a model, eight fruit juice concentrates were screened, including New Zealand fruits. The total phenolic content and the antioxidant capacity, using chemical‐based assays (ferric reducing antioxidant power and oxygen radical absorbance capacity assays), were determined. The potential to protect against oxidative stress in Jurkat cells was also determined. Results indicate that the total phenolic content and antioxidant capacity in chemical‐based assays were strongly correlated. However, the total phenolic content did not dictate the level of protection from oxidative stress in this cell‐based model, suggesting that the type of phenolic compounds present and interactions between them may be important, although the activity of other compounds, such as vitamin C or carotenoids, may also be implicated. This model for screening ingredients may be used to design synergistic combinations of ingredients, and results may provide supportive evidence in the development of functional foods for this and other health targets. 相似文献
98.
Alan M. Allgeier Denise Andersen Michael D. Bartberger Emilio E. Bunel Robert D. Larsen Pingli Liu Thomas Storz Jason S. Tedrow 《Topics in Catalysis》2014,57(17-20):1335-1341
To overcome stability issues associated with the use of an aldehyde in a catalytic reductive amination reaction, a cyclic ketolactol (ω-hydroxylactone) was employed as an aldehyde surrogate to form a γ-aminoacid. The reaction proceeded most favorably over a Pt/C catalyst. The thermodynamics of each step were evaluated using density functional theory calculations, which correctly predicted the dominance of the ring-closed lactol reactant, yet suggested a preference for a ring-opened iminium intermediate upon the initial, slightly endoergic addition of amine substrate. Exoergic hydrogenation of this intermediate provided the thermodynamic driving force for the overall transformation. During development, the reaction was observed to depend significantly on the volumetric gas to liquid mass transfer coefficient (kLa) and this parameter was optimized to ensure successful scale up in a 400 L stirred tank reactor. 相似文献
99.
Sphinganine‐Like Biogenesis of (E)‐1‐Nitropentadec‐1‐ene in Termite Soldiers of the Genus Prorhinotermes
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Dr. Anna Jirošová Dr. Pavel Majer Andrej Jančařík Klára Dolejšová Dr. Richard Tykva Dr. Jan Šobotník Dr. Pavel Jiroš Dr. Robert Hanus 《Chembiochem : a European journal of chemical biology》2014,15(4):533-536
In 1974, (E)‐1‐nitropentadec‐1‐ene, a strong lipophilic contact poison of soldiers of the termite genus Prorhinotermes, was the first‐described insect‐produced nitro compound. However, its biosynthesis remained unknown. In the present study, we tested the hypothesis that (E)‐1‐nitropentadec‐1‐ene biosynthesis originates with condensation of amino acids with tetradecanoic acid. By using in vivo experiments with radiolabeled and deuterium‐labeled putative precursors, we show that (E)‐1‐nitropentadec‐1‐ene is synthesized by the soldiers from glycine or L ‐serine and tetradecanoic acid. We propose and discuss three possible biosynthetic pathways. 相似文献
100.
Unique Crystal Structure of a Novel Surfactant Protein from the Foam Nest of the Frog Leptodactylus vastus
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Dr. Denise Cavalcante Hissa Dr. Gustavo Arruda Bezerra Dr. Ruth Birner‐Gruenberger Dr. Luciano Paulino Silva Dr. Isabel Usón Prof. Dr. Karl Gruber Prof. Dr. Vânia Maria Maciel Melo 《Chembiochem : a European journal of chemical biology》2014,15(3):393-398
Breeding by releasing eggs into stable biofoams (“foam nests”) is a peculiar reproduction mode within anurans, fish, and tunicates; not much is known regarding the biochemistry or molecular mechanisms involved. Lv‐ranaspumin (Lv‐RSN‐1) is the predominant protein from the foam nest of the frog Leptodactylus vastus. This protein shows natural surfactant activity, which is assumed to be crucial for stabilizing foam nests. We elucidated the amino acid sequence of Lv‐RSN‐1 by de novo sequencing with mass‐spectrometry and determined the high‐resolution X‐ray structure of the protein. It has a unique fold mainly composed of a bundle of 11 α‐helices and two small antiparallel β‐strands. Lv‐RSN‐1 has a surface rich in hydrophilic residues and a lipophilic cavity in the region of the antiparallel β‐sheet. It possesses intrinsic surface‐active properties, reducing the surface tension of water from 73 to 61 mN m?1 (15 μg mL?1). Lv‐RSN‐1 belongs to a new class of surfactants proteins for which little has been reported regarding structure or function. 相似文献