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61.
Stout Julie C.; Paulsen Jane S.; Queller Sarah; Solomon Andrea C.; Whitlock Kathryn B.; Campbell J. Colin; Carlozzi Noelle; Duff Kevin; Beglinger Leigh J.; Langbehn Douglas R.; Johnson Shannon A.; Biglan Kevin M.; Aylward Elizabeth H. 《Canadian Metallurgical Quarterly》2011,25(1):1
Objective: PREDICT-HD is a large-scale international study of people with the Huntington disease (HD) CAG-repeat expansion who are not yet diagnosed with HD. The objective of this study was to determine the stage in the HD prodrome at which cognitive differences from CAG-normal controls can be reliably detected. Method: For each of 738 HD CAG-expanded participants, we computed estimated years to clinical diagnosis and probability of diagnosis in 5 years based on age and CAG-repeat expansion number (Langbehn, Brinkman, Falush, Paulsen, & Hayden, 2004). We then stratified the sample into groups: NEAR, estimated to be ≤9 years; MID, between 9 and 15 years; and FAR, ≥15 years. The control sample included 168 CAG-normal participants. Nineteen cognitive tasks were used to assess attention, working memory, psychomotor functions, episodic memory, language, recognition of facial emotion, sensory–perceptual functions, and executive functions. Results: Compared with the controls, the NEAR group showed significantly poorer performance on nearly all of the cognitive tests and the MID group on about half of the cognitive tests (p = .05, Cohen's d NEAR as large as ?1.17, MID as large as ?0.61). One test even revealed significantly poorer performance in the FAR group (Cohen's d = ?0.26). Individual tasks accounted for 0.2% to 9.7% of the variance in estimated proximity to diagnosis. Overall, the cognitive battery accounted for 34% of the variance; in comparison, the Unified Huntington's Disease Rating Scale motor score accounted for 11.7%. Conclusions: Neurocognitive tests are robust clinical indicators of the disease process prior to reaching criteria for motor diagnosis of HD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Research on how individuals monitor their level of comprehension during study paints a picture of learners as being insensitive to many of the factors or conditions of learning that can enhance long-term retention and transfer. In previous research, however, deWinstanley and Bjork (2004) demonstrated that learners—if made sensitive to the memorial benefits of generation in the context of an informative test following study of a text passage in which they had encoded both to-be-read and to-be-generated critical items—then became more effective processors of future to-be-read information presented in a 2nd text passage. In Experiments 1 and 2 of the present research, we explored the potential applicability of this effect by testing whether it could survive certain types of activity-filled delays. In Experiments 3 and 4, we tested whether enhanced processing of contextual information, an encoding strategy that could possibly have been discovered by participants during the testing episode for the 1st text passage, was a potential underlying cause of this effect. Together, our results bring to light an additional benefit of test taking and point to what might be considered necessary and sufficient conditions for leading learners to become more effective processors of future to-be-learned information. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
63.
Vanina A. Angelini Joaquín Orejas María I. Medina Elizabeth Agostini 《Journal of hazardous materials》2011
Chlorophenols are harmful pollutants, frequently found in the effluents of several industries. For this reason, many environmental friendly technologies are being explored for their removal from industrial wastewaters. The aim of the present work was to study the scale up of 2,4-dichlorophenol (2,4-DCP) removal from synthetic wastewater, using Brassica napus hairy roots and H2O2 in a discontinuous stirred tank reactor. We have analyzed some operational conditions, because the scale up of such process was poorly studied. High removal efficiencies were obtained (98%) in a short time (30 min). When roots were re-used for six consecutive cycles, 2,4-DCP removal efficiency decreased from 98 to 86%, in the last cycle. After the removal process, the solutions obtained from the reactor were assessed for their toxicity using an acute test with Lactuca sativa L. seeds. Results suggested that the treated solution was less toxic than the parent solution, because neither inhibition of lettuce germination nor effects in root and hypocotyl lengths were observed. Therefore, we provide evidence that Brassica napus hairy roots could be effectively used to detoxify solutions containing 2,4-DCP and they have considerable potential for a large scale removal of this pollutant. Thus, this study could help to design a method for continuous and safe treatment of effluents containing chlorophenols. 相似文献
64.
Roles of Levies for Sustainable Domestic Water Consumption 总被引:1,自引:1,他引:0
Sustainable development is the modern rhetoric to guide environmental or natural resources management. There are many ways to do this and one is the wider utilization of economic instruments, such as taxes and levies. Although such levies are becoming common in Australia and worldwide, the role of the taxes or levies is still limited. In many cases, these taxes/levies -although environmentally related- have a fiscal rather than a purely environmental motive, for example, the Natural Resources Management (NRM) Levy in South Australia. This study evaluates the NRM levy policy using one NRM region and focussing on the Adelaide urban community. Data was collected through a web-based survey with 770 respondents who answered 59 questions. The research found that community strongly prefers a levy calculated on the volume of water consumed. Respondents also indicated that they would use less water if the levy were calculated on the volume of water consumed. The clear implications of the results suggest that if a tax or levy aims to change water consumption behaviour then it should be based on the volume of water consumed not on property value. 相似文献
65.
ABSTRACTValue in collaborative design research and practice can be understood fundamentally as relationships, materials, processes, contexts, and outcomes that are subjects of and for negotiation. We argue for conceptions of value that move beyond traditional ‘outcomes’ based measurements to reimagine and rearticulate value itself as co-created, emerging from negotiation, relationality and immersion in specific contexts. These understandings of value, we argue, are not rooted in or always knowable through designers’ experiences, even as designers participate in creating them. Using case studies from our research we suggest that value in design collaboration emerges as a question: value to whom, and to what end? We propose that addressing these questions ethically through co-design requires actively engaged, grounded work with collaborators based in three principles: being present for the work, participant making, and co-creating capacity for collaborators to ‘go off and do their thing’. 相似文献
66.
Language requires both storage and composition. However, exactly what is retrieved from memory and what is assembled remains controversial, especially for inflected words. Here, “imageability effects” is introduced as a new diagnostic of storage and a complement to frequency effects. In 2 studies of past-tense morphology, more reliable imageability and frequency effects were found on irregulars than on regulars. An interaction with sex was also observed: Males but not females showed more reliable frequency and imageability effects for irregulars than for regulars; females but not males showed signs of storage for regulars, particularly among higher frequency forms. Overall, the findings validate imageability effects as another diagnostic of storage and suggest that the line between storage and computation is not a simple function; rather, it depends upon the interplay of both item- and subject-specific factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
68.
Elizabeth J. Rundgren 《Natural Gas \u0026amp; Electricity》2016,33(3):22-25
If the twenty-first century has done anything, it's allowed the extrapolation of “personalization” on a global scale. Once limited to purchasing items during set business hours from a local store's inventory, consumers now acquire everything from tailored clothing to kits of gourmet food every minute of the day—sometimes delivered to their doorsteps within hours. This revolution has redefined what it means to “provide” and “consume.” 相似文献
69.
Maria Elizabeth Grabe Ozen Bas Irene Ingeborg van Driel 《The Journal of communication》2015,65(2):300-319
Education‐based knowledge gaps are well‐documented across countries, media platforms, and content. Without exception, knowledge is measured through words not images. Given the centrality of sight in the natural history of Homo sapiens, the extraordinary visual acuity of humans, and the proliferation of screen‐based visual media environments in contemporary life, an experiment was conducted to test the knowledge gap visually. Participants watched 8 audiovisual news stories. Simple recognition of story details and comprehension of that information were tested in verbal and visual modalities. Results offered the first confirmation of the knowledge gap in visual terms. Yet, gaps were significantly smaller employing visual than verbal measures, pointing to the need for continued efforts to develop visual measures for future memory studies. 相似文献
70.