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111.
Xenotransplantation, or the use of animal cells, tissues and organs for humans, has been promoted as an important solution
to the worldwide shortage of organs. While scientific studies continue to be done to address problems of rejection and the
possibility of animal-to-human virus transfer, socio-ethical and legal questions have also been raised around informed consent,
life-long monitoring, animal welfare and animal rights, and appropriate regulatory practices. Many calls have also been made
to consult publics before policy decisions are made. This paper describes the Canadian public consultation process on xenotransplantation
carried out by the Canadian Public Health Association in an arm’s length process from Health Canada, the ministry overseeing
government health policy and regulation. Focusing on six citizen fora conducted around the country patterned after the citizen
jury deliberative approach, the paper describes the citizen panelists’ recommendations to hold off on proceeding with clinical
trials and the rationales behind this recommendation. The consultation process is discussed in the context of constructive
technology assessment, a framework which argues for broader input into earlier stages of technology innovation, particularly
at the technology design stage.
This study was supported by a grant to the first author from the Social Sciences and Humanities Research Council in Canada. 相似文献
112.
Lister hooded rats were trained on a forced-sample T-maze alternation task in an environment lacking spatial landmarks. An
early study of spontaneous alternation on the T-maze had shown that rats use a "spatial sense" to select alternate maze arms
across mazes. As this phenomenon may provide a useful tool for studying the neural substrates of a directional sense, we wished
to confirm this finding on a different version of the T-maze task, with well-trained animals. We found that rats successfully
selected the appropriate maze arm when the choice phase of the task was presented on a second maze, oriented in the same direction,
and located in an adjacent room. However, choice performance fell to chance level when the second maze was oriented 90° relative
to the first. This result suggests that the rats do not simply alternate turns across the two environments, but rather that
they rely on a sense of direction that is carried across environments.
Electronic Publication 相似文献
113.
Noddings N 《Theoretical medicine and bioethics》2002,23(6):441-454
Care theory offers a way to overcome a weaknessof liberalism – its reluctance to intervene inthe private lives of adults. In caring for thehomeless, we must sometimes use a limited formof coercion, but our intervention is alwaysinteractive, and the process of finding asolution is one of negotiation between theneeds expressed by the homeless and the needswe infer for them. 相似文献
114.
Hurewitz F Brown-Schmidt S Thorpe K Gleitman LR Trueswell JC 《Journal of psycholinguistic research》2000,29(6):597-626
Two experiments are reported which examine children's ability to use referential context when making syntactic choices in language production and comprehension. In a recent on-line study of auditory comprehension, Trueswell, Sekerina, Hill, and Logrip (1999) examined children's and adults' abilities to resolve temporary syntactic ambiguities involving prepositional phrases (e.g., “Put the frog on the napkin into ¨”). Although adults and older children used the referential context to guide their initial analysis (pursuing a destination interpretation in a one-frog context and a modifier interpretation in a two-frog context), 4 to 5-year olds' initial and ultimate analysis was one of destination, regardless of context. The present studies examined whether these differences were attributable to the comprehension process itself or to other sources, such as possible differences in how children perceive the scene and referential situation. In both experiments, children were given a language generation task designed to elicit and test children's ability to refer to a member of a set through restrictive modification. This task was immediately followed by the “put” comprehension task. The findings showed that, in response to a question about a member of a set (e.g., “Which frog went to Mrs. Squid's house?”), 4- to 5-year-olds frequently produced a definite NP with a restrictive prepositional modifier (e.g., “The one on the napkin”). These same children, however, continued to misanalyze put instructions, showing a strong avoidance of restrictive modification during comprehension. Experiment 2 showed that an increase in the salience of the platforms that distinguished the two referents increased overall performance, but still showed the strong asymmetry between production and comprehension. Eye movements were also recorded in Experiment 2, revealing on-line parsing patterns similar to Trueswell et al.: an initial preference for a destination analysis and a failure to revise early referential commitments. These experiments indicate that child–adult differences in parsing preferences arise, in part, from developmental changes in the comprehension process itself and not from a general insensitivity to referential properties of the scene. The findings are consistent with a probabilistic model for uncovering the structure of the input during comprehension, in which more reliable linguistic and discourse-related cues are learned first, followed by a gradually developing ability to take into account other more uncertain (or more difficult to learn) cues to structure. 相似文献
115.
Arthur C. Bohart 《Journal of Psychotherapy Integration》2000,10(2):127-149
I first briefly review the dodo bird verdict and suggest that we should be responding to it by looking for a new way to conceptualize how therapy works. Then I describe the dominant medical or treatment model of psychotherapy and how it puts the client in the position of a dependent variable who is operated on by supposedly potent therapeutic techniques. Next I argue that the data do not fit with this model. An alternative model is that the client is the most important common factor and that it is clients' self-healing capacities which make therapy work. I then argue that therapy has two phases—the involvement phase and the learning phase—and that the involvement phase is the most important. I next review the five learning opportunities provided by therapy. Finally, I argue that a relational model of therapy focused on consultation, collaboration, and dialogue is better than a treatment model. 相似文献
116.
Woodbury M 《Science and engineering ethics》2000,6(2):235-244
Business people repeatedly asked Computer Professionals for Social Responsibility (CPSR) to recommend a policy to deal with
email and voicemail. After many such requests to our organization, we attempted to construct guidelines that we could endorse.
This paper outlines the guidelines that we proposed and the public reaction to them. The paper discusses the tensions inherent
in a business environment, and the means of identifying ethical behavior for both companies and their employees.
A version of this paper was presented at ETHICOMP98, the Fourth International Conference on Ethical Issues of Information
Technology, March 25–27, 1998. Erasmus University, the Netherlands.
Dr. Woodbury is the former Chair of CPRS. Computer Professionals for Social Responsibility. She is also a curriculum developer
and faculty member of the Information Group of the Women’s International University (ifu) in Germany in 2000. 相似文献
117.
Scientific misconduct includes the fabrication, falsification, and plagiarism (FFP) of concepts, data or ideas; some institutions
in the United States have expanded this concept to include “other serious deviations (OSD) from accepted research practice.”
It is the absence of this OSD clause that distinguishes scientific misconduct policies of the past from the “research misconduct”
policies that should be the basis of future federal policy in this area. This paper introduces a standard for judging whether
an action should be considered research misconduct as distinguished from scientific misconduct: by this standard, research
misconduct must involve activities unique to the practice of science and must have the potential to negatively affect the
scientific record. Although the number of cases of scientific misconduct is uncertain (only the NIH and the NSF keep formal
records), the costs are high in terms of the integrity of the scientific record, diversions from research to investigate allegations,
ruined careers of those eventually exonerated, and erosion of public confidence in science. Existing scientific misconduct
policies vary from institution to institution and from government agency to government agency; some have highly developed
guidelines that include OSD, others have no guidelines at all. One result has been that the federal False Claims Act has been
used to pursue allegations of scientific misconduct. As a consequence, such allegations have been adjudicated in federal courts,
rather than judged by scientific peers. The federal government is now establishing a first-ever research misconduct policy
that would apply to all research funded by the federal government regardless of which agency funded the research or whether
the research was carried out in a government, industrial or university laboratory. Physical scientists, who up to now have
only infrequently been the subject of scientific misconduct allegations, must nonetheless become active in the debate over
research misconduct policies and how they are implemented since they will now be explicitly covered by this new federal wide
policy.
Disclaimer: The authors are grateful for the support for conduct of this research provided by the United States Department of Energy
(DOE). The views expressed in this paper are solely those of the authors and were formed and expressed without reference to
positions taken by DOE or the Pacific Northwest National Laboratory (PNNL). The views of the authors are not intended either
to reflect or imply positions of DOE or PNNL. 相似文献
118.
Based on Schmidt's (1975) variability of practice hypothesis, this study examined acquisition and transfer of a gross motor skill, namely tossing, in 58 patients with Alzheimer's disease (AD) and 58 healthy older adults under constant, blocked, and random practice conditions. While healthy older adults were able to learn the tossing task equally well under the three practice conditions, only AD patients receiving constant practice showed significant improvements. Tests of intermediate transfer yielded the expected random practice advantage in healthy controls but not AD patients. None of the practice conditions facilitated intermediate transfer in AD patients; however, constant practice did benefit these impaired individuals on tests of near transfer. These results indicate that the variability of practice hypothesis does not extend to AD patients. As motor learning and transfer were clearly a function of constant practice, future attempts to retrain basic activities of daily living in AD patients should emphasize consistency in training. 相似文献
119.
Young children are readily able to use known labels to constrain hypotheses about the meanings of new words under conditions of referential ambiguity. At issue is the kind of information children use to constrain such hypotheses. According to one theory, children take into account the speaker's intention when solving a referential puzzle. In the present studies, children with autism were impaired in monitoring referential intent, but were equally successful as normally developing 24-month-old toddlers at mapping novel words to unnamed items under conditions of referential ambiguity. Therefore, constraints that lead the child to map a novel label to a previously unnamed object under these circumstances are not solely based on assessments of speakers' intentions. 相似文献
120.
We assessed the impact of visual similarity on written word identification by having participants learn new words (e.g. BANARA) that were neighbours of familiar words that previously had no neighbours (e.g. BANANA). Repeated exposure to these new words made it more difficult to semantically categorize the familiar words. There was some evidence of interference following an initial training phase, and clear evidence of interference the following day (without any additional training); interference was larger still following more training on the second day. These findings lend support to models of reading that include lexical competition as a key process. 相似文献