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201.
Developing human-nonhuman chimeras in human stem cell research: ethical issues and boundaries 总被引:1,自引:0,他引:1
The transplantation of adult human neural stem cells into prenatal non-humans offers an avenue for studying human neural cell development without direct use of human embryos. However, such experiments raise significant ethical concerns about mixing human and nonhuman materials in ways that could result in the development of human-nonhuman chimeras. This paper examines four arguments against such research, the moral taboo, species integrity, "unnaturalness," and human dignity arguments, and finds the last plausible. It argues that the transfer of human brain or retinal stem cells to nonhuman embryos would not result in the development of human-nonhuman chimeras that denigrate human dignity, provided such stem cells are dissociated. The article provides guidelines that set ethical boundaries for conducting such research that are consonant with the requirements of human dignity. 相似文献
202.
The role of metabotropic glutamate receptors and cortical adaptation in habituation of odor-guided behavior 下载免费PDF全文
Decreases in behavioral investigation of novel stimuli over time may be mediated by a variety of factors including changes in attention, internal state, and motivation. Sensory cortical adaptation, a decrease in sensory cortical responsiveness over prolonged stimulation, may also play a role. In olfaction, metabotropic glutamate receptors on cortical afferent pre-synaptic terminals have been shown to underlie both cortical sensory adaptation and habituation of odor-evoked reflexes. The present experiment examined whether blockade of sensory cortical adaptation through bilateral infusion of the group III metabotropic glutamate receptor antagonist cyclopropyl-4-phosphonophenylglycine (CPPG) into the anterior piriform cortex could reduce habituation of a more complex odor-driven behavior such as investigation of a scented object or a conspecific. The results demonstrate that time spent investigating a scented jar, or a conspecific, decreases over the course of a continuous 10 minute trial. Acute infusion of CPPG bilaterally into the anterior piriform cortex significantly enhanced the time spent investigating the scented jar compared to investigation time in control rats, without affecting overall behavioral activity levels. Infusions into the brain outside of the piriform cortex were without effect. CPPG infusion into the piriform cortex also produced an enhancement of time spent investigating a conspecific, although this effect was not significant. 相似文献
203.
Pelham WE Massetti GM Wilson T Kipp H Myers D Standley BB Billheimer S Waschbusch DA 《Journal of attention disorders》2005,9(1):248-260
The Academic and Behavioral Competencies (ABC) Program, a schoolwide program to reduce classroom disruption and encourage rule following, academic task completion, and homework completion, is described. The program was initially developed and implemented in an elementary school with a high-risk population. Data from teachers, parents, and children indicate high levels of satisfaction with the program. In addition, unobtrusive measures of program impact, reported as reductions in referrals to the principal's office, suspensions, and increases in homework completion rates relative to the year prior to implementation of the program, suggest a preliminary positive impact of the program. A replication is reported for another school district, with teacher evaluations of satisfaction and effectiveness reported, supporting the flexibility and adaptability of the program. Although the present article does not constitute a systematic evaluation of the ABC Program, it presents preliminary data on the process of implementation and stakeholder satisfaction. 相似文献
204.
The aim of this research was to examine age differences in children's perceptions of dangerous substances. Children's responses to photographs of child models encountering alcohol, a syringe, medicine, glue, and household bleach were coded for recognition of substance, awareness of potential danger, and understanding of danger or harm. Responses from 59 children (28 girls and 31 boys, who were all children of the required age in an urban primary school) were compared across three age groups (6-7 years, 8-9 years, and 10-11 years). 15 to 18 of 20 children in each of three age groups recognised all the dangerous substances. Significant differences across age groups were found for awareness of the potential harm from alcohol, glue, and medicine, but not for the syringe or bleach. Children reported less serious consequences from ingesting alcohol than other substances, the consequences of sniffing glue tended to be confused with the sticking properties of glue, children's understanding of transmission of germs, disease, and AIDS through syringes was varied, and there was a tendency among the older children to underestimate the potential harm of self-administration of medicines. Findings were discussed in relation to children's concepts of danger and safety education. 相似文献
205.
Throughout the U.S., state laws require professionals who work with children to report cases of suspected child abuse to child protection services. Both practically and conceptually, however, significant problems arise from a lack of clarity regarding the threshold that has been set for reporting. Specifically, there is no consensus as to what constitutes reasonable suspicion, and little direction for how mandated reporters should gauge their legal and professional responsibilities when they harbor suspicion. In this paper we outline the context of the problem, discuss the nature and scope of its conceptual underpinnings, and offer recommendations for moving towards a concrete, practical solution. 相似文献
206.
207.
Catalano GD 《Science and engineering ethics》2004,10(2):409-415
A senior level capstone design experience has been developed and offered with a particular emphasis on many of the professional
issues raised in Accreditation Board for Engineering and Technology (ABET) Engineering Criterion IV. The course has sought
to develop student awareness of the ethical foundation of the engineering profession, the global and societal framework within
which engineers practice, and the environmental impact on engineering. The capstone design course also focused upon improving
the technical communications skills of the graduating senior class with both extensive instruction in writing and multiple
workshops dealing with the art of making an effective oral presentation. The effectiveness of the design course was assessed
using Kirkpatrick’s model for evaluating training programs.
An earlier version of this paper was presented at the “Ethics and Social Responsibility in Engineering and Technology” meeting,
New Orleans, 2003. 相似文献
208.
Although marital and relationship support programs are available for couples, few churches offer comprehensive marital and relationship ministry (MRM). This research examined MRM topics and formats desired by congregants and advocated adoption by clergy of MRM as a tenant of pastoral care. Eight faith communities in a Midwestern city were non-randomly selected for ethnic and denominational diversity. Overall analyses indicated congregants desired specific areas of marital and relationship ministry that included communication, family, and enrichment topics. 相似文献
209.
Sex and sexual orientation related differences in processing of happy and sad facial emotions were examined using an experimental facial emotion recognition paradigm with a large sample (N = 240). Analysis of covariance (controlling for age and IQ) revealed that women (irrespective of sexual orientation) had faster reaction times than men for accurate identification of facial emotion and were more accurate in identifying male faces than female ones, whereas men performed the same regardless of the sex of the face. However, there were no overall sex differences in accuracy. These findings suggest a limited role for sex in the perception of facial affect. 相似文献
210.
Predicting stability and change in toddler behavior problems: contributions of maternal behavior and child gender 总被引:1,自引:0,他引:1
This study examined the stability and continuity of early-identified behavior problems and the factors associated with this stability. Children and their mothers (N=125) were seen when the children were 2 and 4 years of age. Maternal reports of child externalizing behavior and laboratory observations of child noncompliance were stable from age 2 to age 4. Early externalizing behaviors decreased over time; however, child noncompliance in the laboratory did not. Although few associations were found between maternal positive behavior and child behavior problems, maternal controlling behavior was related to increases in child behavior problems, particularly at high levels of both prior noncompliance and prior maternal control. Child noncompliance was predictive of increases in maternal controlling behavior over time. 相似文献