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221.
Kakuk P 《Science and engineering ethics》2008,14(3):357-375
The discursive explosion that was provoked by the new genetics could support the impression that the ethical and social problems posed by the new genetics are somehow exceptional in their very nature. According to this view we are faced with special ethical and social problems that create a challenge so fundamental that the special label of genethics is needless to justify. The historical account regarding the evolution of the gene concepts could serve us to highlight the limits of what we know about genes and what we can do with genes. The widespread notion about the exceptionality of genetic knowledge and its applicative possibilities is hardly justifiable and leads to misunderstandings regarding the conceptualization of the ethical and social problems we might face. Following a more realistic interpretation of the role of genes in human life we might avoid a whole set of fictive dilemmas and counterproductive regulatory efforts in bioethics. Bioethical discourse should move from the gene-centered scientific discourse toward the more sophisticated and complex discourses where human development represented as a matter of complex interactions between genomes and environments, between genes, educational factors, nutritional regimes, and other different developmental resources. If a gene is seen as one among the different developmental resources that are shaping a given human trait then both genethics and genetic exceptionalism could hardly be represented as a justified approach in discussing the ethical and social problems of genetics. 相似文献
222.
Toshihisa Sato Motoyuki Akamatsu 《Transportation Research Part F: Traffic Psychology and Behaviour》2008,11(4):242-258
This paper focuses on modeling and predicting the influence of a vehicle’s velocity and the relative position between a driver’s vehicle and a vehicle to the front or rear on the onset of driver preparations for making a right turn at an intersection. Repeated experiments were carried out on a public road to measure driver preparations, including releasing the accelerator pedal, moving the right foot to cover the brake pedal, and activating the turn signal, as well as to record vehicle velocity and the relative distances to the leading and following vehicles. Structural equation modeling was applied to estimate these relationships quantitatively. Two separate latent variables accounting for the interaction between the driver’s vehicle and leading or following vehicles, and the onset point where driving behavior changes from straight mode to preparation mode before a right turn, were introduced in the specification of the structural equation model. The model estimates and testing indicate that the proposed structural equation model represents well the relationship hypothesized by observational analysis: that the vehicle velocity and the traffic conditions surrounding the driver’s vehicle strongly influence the driver’s deceleration and more weakly influenced turn signal activation. The proposed structural equation model contributes to the prediction of the onset locations of covering the brake pedal and activating the turn signal based on the vehicle velocity and the relative distances to the front and rear vehicles when the accelerator pedal is released. The prediction accuracy is high compared with predictions in which the vehicle velocity and the headway or rear distances are not taken into account or predictions using a single regression model with one independent variable, namely driving speed. Finally, a possible new addition to in-vehicle navigation systems that detects unusual driver behavior by predicting the driver’s preparatory maneuvers is discussed. 相似文献
223.
This paper analyzes the sum score based (SSB) formulation of the Rasch model, where items and sum scores of persons are considered
as factors in a logit model. After reviewing the evolution leading to the equality between their maximum likelihood estimates,
the SSB model is then discussed from the point of view of pseudo-likelihood and of misspecified models. This is then employed
to provide new insights into the origin of the known inconsistency of the difficulty parameter estimates in the Rasch model.
The main results consist of exact relationships between the estimated standard errors for both models; and, for the ability
parameters, an upper bound for the estimated standard errors of the Rasch model in terms of those for the SSB model, which
are more easily available.
The authors acknowledge partial financial support from the FONDECYT Project No. 1060722 from the Chilean Government, and the
BIL05/03 grant to P. De Boeck, E. Lesaffre and G. Molenberghs (Flanders) for a collaboration with G. del Pino, E. San Martín,
F. Quintana and J. Manzi (Chile). 相似文献
224.
大型教学医院应加强肿瘤疾病数据库的建设 总被引:2,自引:0,他引:2
建立恶性肿瘤疾病数据库(carcinoma cases database,CCD)来管理肿瘤患者的临床资料是临床医学信息化、现代化的迫切要求和必然趋势。大型教学医院应充分利用资源优势,遵循可行性、实用性原则,加强CCD的建设,以实现对肿瘤病人临床资料规范、系统、便捷的管理,更好地开展临床、教学和科研工作,评估肿瘤疾病的疗效及完善病例的随访追踪。 相似文献
225.
Albert Maydeu-Olivares 《Psychometrika》2006,71(1):57-77
Discretized multivariate normal structural models are often estimated using multistage estimation procedures. The asymptotic
properties of parameter estimates, standard errors, and tests of structural restrictions on thresholds and polychoric correlations
are well known. It was not clear how to assess the overall discrepancy between the contingency table and the model for these
estimators. It is shown that the overall discrepancy can be decomposed into a distributional discrepancy and a structural
discrepancy. A test of the overall model specification is proposed, as well as a test of the distributional specification
(i.e., discretized multivariate normality). Also, the small sample performance of overall, distributional, and structural
tests, as well as of parameter estimates and standard errors is investigated under conditions of correct model specification
and also under mild structural and/or distributional misspecification. It is found that relatively small samples are needed
for parameter estimates, standard errors, and structural tests. Larger samples are needed for the distributional and overall
tests. Furthermore, parameter estimates, standard errors, and structural tests are surprisingly robust to distributional misspecification.
This research was supported by the Department of Universities, Research and Information Society (DURSI) of the Catalan Government,
and by grants BSO2000-0661 and BSO2003-08507 of the Spanish Ministry of Science and Technology. 相似文献
226.
Reactive and proactive aggression: Similarities and differences 总被引:3,自引:1,他引:2
The purpose of the current study was to elaborate the nomological net surrounding the constructs of reactive (RA) and proactive aggression (PA). Typically examined in the context of children, the current study utilized a sample of 211 young adults to examine the relations between reactive and proactive aggression and measures of general personality and social information processing, as well as maladaptive behavioral correlates such as crime, substance use, and riskier sex. Both raw and residualized scores were examined. Using raw scores, the primary differences between RA and PA were related to Neuroticism (i.e., RA more strongly related) and externalizing behaviors (i.e., PA more strongly). The authors comment on the similarity of findings when using raw scores and the divergence of findings using residualized scores and argue for a cautious interpretation of differences based on residualized scores. The authors conclude that the role of Neuroticism warrants further exploration as a means for understanding the heterogeneity of aggressive behavior. 相似文献
227.
Carl S. Helrich 《Zygon》2006,41(3):543-566
Abstract. I present a partially historical discussion of the basis of the quantum theory in nonmathematical terms using human knowledge and consciousness as an underlying theme. I show that the philosophical position in both classical and quantum theory is the experimental and mathematical philosophy of Isaac Newton. Because almost all the systems we deal with are multicomponent, we must consider the limitations and openness imposed by thermodynamics on our claims in both classical and quantum treatments. Here the reality of measurement stands in the way of any simple picture but also provides the basis for considerations of free will. Particular care is taken with the concepts of quantum measurement, entanglement, and decoherence because of their importance in the discussion. 相似文献
228.
Jennifer L. Ramsey-Rennels Judith H. Langlois 《Current directions in psychological science》2006,15(2):59-62
ABSTRACT— Infants show an interesting asymmetry in face processing: They are more fluent in processing female faces than they are at processing male faces. We hypothesize that such processing asymmetry results from greater experience with female faces than with male faces early in development. Asymmetrical face processing may have long-lasting implications for development of face recognition, development of knowledge structures regarding females and males, and social-information processing. We encourage researchers to use both female and male faces in their face-perception research and to conduct separate analyses for female and male faces. 相似文献
229.
精神医学是临床医学的一个分枝,是高度复杂的一门科学,站在哲学的角度反思,信息系统控制科学方法渗透于精神医学的历史发展过程和临床工作的资料收集、诊断、治疗等各个环节,以及精神医学的科研工作中,还启迪着我国精神卫生事业的发展方向。 相似文献
230.
心境对情绪信息加工的影响 总被引:1,自引:0,他引:1
该文考察在自然情境和人为诱发的情境下,心境对不同情绪信息加工过程的影响,验证特质一致性假设。采用实验研究和问卷调查相结合的方法,并以SPSS11.5进行数据处理。结果显示,在自然情境下,心境对于情绪信息加工的影响不是很明显;而在人为诱发的情境下,验证了心境一致性效应。 相似文献