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81.
Explored the relationship between identity and changes in physical functioning over the adult years. 242 adults (aged 40–95 yrs) rated themselves in 20 areas of normative functioning and identity processes. Measures included the Physical and Cognitive Change Scale, the Identity and Experiences Scale—Specific Aging, and the Rosenberg Self-Esteem Questionnaire. The findings indicate that adults as young as 40 are sensitive to age-related changes. Those 65 and older exhibited greater sensitivity to changes in competence. Identity assimilation was used most by adults under 65, particularly in the area of cognitive functioning. For individuals in both age groups, identity assimilation was positively related to self-esteem. The findings suggest that individuals may make behavioral adjustments without ruminating or becoming preoccupied, a strategy that may promote healthy adaptation to the aging process. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Many techniques used to evaluate biological community data for effects of wastewater discharge do not discriminate between change and harmful change. A coefficient using the ratio of numbers of taxa lost between an unaffectd reference community and a pollution affected community, to the total number of taxa found in the affected community, provides a better evaluation of detrimental change. The value of the coefficient is determined by both the observed change in community richness as well as change in taxonomic similarity. The coefficient produces values from zero indicating no harmful change to infinity where there is complete loss of a community. Macroinvertebrate data suggests that values exceeding 0.8 are indicative of excessively harmful change in those communities. 相似文献
83.
The EPA Bottle Test was compared to a short-term algal bioassay method (Oxygen Evolution Assay) for detecting waterborne herbicides and metals. Although the Bottle Test proved to be a more sensitive assay system, the responses of the two bioassays correlated well. The Oxygen Evolution Assay may be useful as a rapid preliminary screening method for determining which chemicals should undergo further testing. In both bioassays, differences were observed in the results of experiments conducted in the standard algal growth medium and in nutrient-enriched water samples, suggesting that water chemistry plays an important role in the determination of specific toxicity thresholds for algae. 相似文献
84.
Susan J. Masten Kuan‐Chung Chen Jaime Graulau Subhash L. Kari Kyung‐Hyuk Lee 《工程教育杂志》2002,91(1):69-80
The use of computer‐based technology is becoming more prevalent in the classroom. As a part of an educational research project sponsored by the GE Foundation, strategies for augmenting a course, Introduction to Environmental Engineering (CE 280), were investigated including cross‐disciplinary experiences in teamwork, design, and the use of advanced teaching technologies such as the web. Interactive tools to assist student learning were developed and refined. Efforts have focused on developing an extensive website, web‐based quizzes and homework assignments, and tutorials. Base groups were used to provide both intellectual and emotional support to students. This paper summarizes the development of this course and the impact of rapid feedback on the progression of student understanding. 相似文献
85.
Sustainability is one of the ‘buzz’ words that is highly discussed in the area of packaging nowadays. For many product manufacturing business, incorporation of sustainability principles into their business practice can only be visualized by others in the end product through packaging. Besides the criteria, underlying concepts and principles, most discussions towards achieving goals for sustainable packaging are focused on details of models and practices adopted by the industry, and the effectiveness and practicality of these practices in balancing the economic profits and environmental benefits. While the economic and environmental bases of packaging sustainability have been examined and discussed in great detail, the same is not true of social consideration. Although the success of sustainable packaging development actually relies on both technological development and social considerations, many of the social aspects of sustainable packaging are often overlooked. Although many companies have been putting the efforts and initiatives to elevate sustainability from an abstract goal into an immediate priority, relatively little is known about the consumers' insights of packaging sustainability. Recognizing the consumers as the final arbiter of the success of sustainable packaging, this paper will explore consumers' perceptions on the sustainable packaging concept, their perceptions of the impact to the environment and discuss factors that drive consumers' preferences and purchase decision. Discussion and information gathered in this paper is aimed to stimulate understanding on the importance of the social dimension of packaging sustainability and its role in supporting the efforts to improve sustainability practice. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
86.
87.
Wenke Friedrichs Bastian Ohler Walter Langel Susanna Monti Susan Köppen 《Advanced Engineering Materials》2011,13(10):B334-B342
Classical molecular dynamics simulations of tropocollagen molecules on rough titania surfaces are presented. On the basis of plane rutile (100), two models for surface roughness have been adopted: (1 × 3) microfacets with dimensions of less than 14 Å had only minor influence on the adsorption of a triple helical structure with a diameter of about 16 Å. After increasing the roughness by terraces, steric hindrance of helix binding was observed. A model for telopeptide capping of the collagen triple helices was developed. The highly flexible telopeptide structures mediated adsorption on the surface and inserted into grooves of both surface models. The telopeptide β‐turn motifs at the C‐terminus of the tropocollagen interact with specific receptor regions of the triple helices. This intermolecular process seems to be entropy driven and may be the first step of assembling helices to ordered fibrils. Interaction between telopeptide and triple helix seems to be in competition with the rather enthalpy controlled surface adsorption of single collagen molecules. 相似文献
88.
Susan D. F. Kustas A. B. Kellogg R. A. Carroll J. D. Michael J. R. Karaman I. 《Metallurgical and Materials Transactions A》2021,52(9):4090-4099
Metallurgical and Materials Transactions A - Equal channel angular extrusion (ECAE) of 49Fe-49Co-2V, also known as Hiperco® 50A or Permendur-2V, greatly improves the strength and ductility of... 相似文献
89.
90.
Susan M. O’Donnell Rakesh K. Gelda Steven W. Effler Donald C. Pierson 《Canadian Metallurgical Quarterly》2011,137(8):678-688
Effective simulation of the fate and transport of runoff event inflows is an important goal of many water quality modeling initiatives. The set-up and testing of a two-dimensional hydrodynamic transport model is documented for a water supply reservoir, Schoharie Reservoir, New York, that uses specific conductance (SC) as a conservative tracer and focuses on fate and transport of runoff event inputs, particularly the plunging of density currents in summer and fall. Model testing is supported by temporally detailed measurements of meteorological, operational, and tributary (temperature and SC) model drivers, and temporally and spatially replete in-reservoir patterns of SC following multiple runoff events, obtained with a combination of robotic monitoring platforms and gridding with rapid profiling instrumentation. Specific conductance is demonstrated to be an ideal tracer because of the distinct tributary signals and subsequent in-reservoir signatures imparted from runoff events and its close coupling to turbidity patterns that are primary water quality concerns for managers. The model is demonstrated to perform well in simulating in-reservoir signatures of SC following multiple runoff events over the spring to fall interval of 2003, including vertical, longitudinal, and temporal patterns, and features of the thermal stratification regime for the same interval. The validated model is applied in a probabilistic manner on the basis of a 61-year record (239 runoff events) of model drivers to provide a robust representation of the transport of runoff event inputs relative to the location of the water supply intake. This application demonstrates the entry of runoff event inflows as plunging density currents in summer and fall is a recurring phenomenon for this reservoir. 相似文献