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71.
Mounting evidence suggests that the human impact on the planet is reaching the point where the Earth's ecosystems will not be able to support the level of human occupation. The global economy also seems to be generating income disparities that threaten the social stability of even the most developed economies. Although both these trends are rooted in the operation of the global market economy, standard economics has surprisingly little to offer in the way of policies that might allow us to survive the twenty-first century with our current social and environmental systems intact. This article examines our current predicament from the point of view of neoclassical welfare economics and the alternative framework of ecological economics. We argue that ecological economics, by placing the study of economics squarely within human society and ecosystems, can lead the way to make economics both scientifically credible and policy relevant. 相似文献
72.
生殖系基因治疗的技术和伦理问题 总被引:3,自引:1,他引:2
生殖系基因治疗是通过对生殖系细胞的基因修饰,给该细胞发育而来的整个有机体及其后代带来永久性的遗传纠正。本文着重对生殖系治疗的现有技术条件,存在技术问题及各种观点作一归纳,主要试图反映生殖系基因治疗的科学背景及当代人的思考,希望有助于人们的思考。 相似文献
73.
Jackson F 《Science and engineering ethics》1998,4(2):155-170
The Human Genome Project (HGP) represents a massive merging of science and technology in the name of all humanity. While the
disease aspects of HGP-generated data have received the greatest publicity and are the strongest rationale for the project,
it should be remembered that the HGP has, as its goal the sequencing of all 100,000 human genes and the accurate depiction of the ancestral and functional relationships among these genes. The HGP will
thus be constructing the molecular taxonomic norm for humanity. Currently the HGP genomic baseline is almost exclusively skewed
toward North Atlantic European lineages through the extensive use of the Centre d’études du Polymorphisme Humaine (CEPH) data
set. More recently, the HGP has shifted to the use of volunteer donors since adequate informed consent had not been secured
from the CEPH families. No evidence exists that either the CEPH families or the current volunteers are the most appropriate
demographic or evolutionary lineages for the functional genomic studies that will guide production of new DNA based drugs,
targeted therapeutics and gene-based diagnostics. The lack of scientific representativeness of the HGP is a serious impediment
to its broad applicability. Yet this can be remedied, and five alternative sampling strategies are presented. In response
to the current exclusionary design of the HGP, there is noteworthy caution and skepticism in the African American community
concerning genetic studies. The Manifesto on Genomic Studies Among African Americans reflects both a desire to be systematically included in federally funded genomic studies and a desire to maintain some control
over the interpretation and application of research results. Representative sampling in the HGP is seen as an international
human rights issue with domestic ethical implications. 相似文献
74.
Since the observations of O. Pfungst the use of human-provided cues by animals has been well-known in the behavioural sciences
(“Clever Hans effect”). It has recently been shown that rhesus monkeys (Macaca mulatta) are unable to use the direction of gazing by the experimenter as a cue for finding food, although after some training they
learned to respond to pointing by hand. Direction of gaze is used by chimpanzees, however. Dogs (Canis familiaris) are believed to be sensitive to human gestural communication but their ability has never been formally tested. In three
experiments we examined whether dogs can respond to cues given by humans. We found that dogs are able to utilize pointing,
bowing, nodding, head-turning and glancing gestures of humans as cues for finding hidden food. Dogs were also able to generalize
from one person (owner) to another familiar person (experimenter) in using the same gestures as cues. Baseline trials were
run to test the possibility that odour cues alone could be responsible for the dogs’ performance. During training individual
performance showed limited variability, probably because some dogs already “knew” some of the cues from their earlier experiences
with humans. We suggest that the phenomenon of dogs responding to cues given by humans is better analysed as a case of interspecific
communication than in terms of discrimination learning.
Received: 30 May 1998 / Accepted after revision: 6 September 1998 相似文献
75.
Learning of fixed arbitrary sequences proceeds by idiosyncratic subsequencing and assembly of the resulting subsequences. An error item that just precedes a subjective subsequence is a closely constrained member of that subsequence. Identification and characterization of subjective subsequences were accomplished by analyses of forward serial learning, free recall, and backward serial learning. We conclude that ordinary serial learning cannot be represented by traditional continuous-process theories, but instead must be treated by an organizational model. 相似文献
76.
John Robert Anderson 《Cognitive psychology》1974,6(4):451-474
Three experiments are reported in which subjects learn propositions like A hippie is in the park. The experiments manipulate the number of such propositions involving a particular person (e.g., hippie) or a particular location (e.g., park). After learning the material, subjects are asked to judge whether particular probe propositions are from the study set. Times to make these judgments about probe propositions increase with the number of study propositions involving the person or location used in the probe proposition. A model is presented which assumes a subject simultaneously accesses memory from all concepts in a probe proposition and serially searches through all study propositions involving each concept. Search of memory terminates as soon as one search process from a concept finds the probe proposition or exhausts the study propositions attached to that concept. 相似文献
77.
Women in four high-status, male-dominated professions—architecture, law, medicine, and psychology—are described in terms of a variety of historical, social, and career variables. The women share common antecedents of their vocational choices and similar perceptions of their work, but the occupational groups are dissimilar on a number of dimensions. Psychologists stand in particular contrast to the other three groups of professionals, describing experiences and career patterns less in conflict with stereotypic female roles. These contrasts may reflect differences in the sex-typed characterizations of the professions even though all are male-dominated. 相似文献
78.
In most social evaluation research it is difficult to achieve the degree of experimental rigor possible in an applied behavioral study. This study illustrates how the evaluation researcher can increase experimental rigor in the analysis of social interventions. In the first evaluation, a variation of the time-series design that offered maximum experimental control given the limitations of the situation, was employed to evaluate the effects of a specialized home-burglary police patrol. This design revealed that no effects could be attributed to the patrol. In the second evaluation, a multiple baseline-like design was possible in determining the effects of a police walking patrol. This design revealed that the patrol produced an increase in crime reporting but not in arrests. Social interventions often occur in a manner that allows varying degrees of experimental analysis. The evaluation researcher must attain optimal experimental analysis given the limitations of each social intervention. 相似文献
79.
The combined and separate effects of parent-presented models and praise on specific vocalizations of three children (15, 17, and 20 months old) were investigated. The frequency of a specific vocalization was higher when parents modeled and praised it than when they did not. In addition, modeling and praise, when used in combination, had a greater effect on the frequency of specific vocalizations than when used separately. Three additional parents were asked to attempt, by any means they wished, to increase the frequency of a specific vocalization by their children. These parents used modeling almost, exclusively, and the children did not exhibit the specific vocalizations as frequently as did the children whose parents were instructed both to model and praise specific vocalizations. 相似文献
80.
With limited efficacy of medications for symptom relief, non-medication treatments may play an important role in the treatment of irritable bowel syndrome (IBS), the most common functional gastrointestinal (GI) disorder. This study aimed to evaluate the efficacy of two self-regulation strategies for symptom relief and mood management in IBS patients. Thirty-five adult participants meeting ROME III criteria for IBS were enrolled, 27 of the 35 participants (77%) completed treatment and pre- and post-treatment visits (89% women, 11% men; M (SD) age = 36 (13)), and 20 of the 27 (74%) completed a 6-month follow-up. Participants were randomly assigned to 16 biweekly group sessions of Iyengar yoga or a walking program. Results indicated a significant group by time interaction on negative affect with the walking treatment showing improvement from pre- to post-treatment when compared to yoga (p < .05). There was no significant group by time effect on IBS severity. Exploratory analyses of secondary outcomes examined change separately for each treatment condition. From pre- to post-treatment, yoga showed significant decreases in IBS severity measures (p < .05), visceral sensitivity (p < .05), and severity of somatic symptoms (p < .05). Walking showed significant decreases in overall GI symptoms (p < .05), negative affect (p < .05), and state anxiety (p < .05). At 6-month follow-up, overall GI symptoms for walking continued to significantly decline, while for yoga, GI symptoms rebounded toward baseline levels (p < .05). When asked about self-regulated home practice at 6 months, significantly more participants in walking than in yoga practiced at least weekly (p < .05). In sum, results suggest that yoga and walking as movement-based self-regulatory behavioral treatments have some differential effects but are both beneficial for IBS patients, though maintenance of a self-regulated walking program may be more feasible and therefore more effective long term. 相似文献