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231.
The AMA Council on Ethical and Judicial Affairs (CEJA) has written a position paper on how social medical use challenges medical professionalism. The report offers persuasive ethical and practical guidelines for nonclinical internet use, specifically for social networking. This commentary provides a framework from which to apply these guidelines, but adds that there may be important situations in which physicians are not able to act in accordance. The guidelines call for professional reporting of questionable online portrayals or behaviors, but this commentary argues that this may be not only cumbersome to implement, but may violate aspects of constitutional rights. While online social networking may in many ways be a new application of old challenges, there may be other aspects that require novel approaches to medical professionalism.  相似文献   
232.
Self‐produced locomotion is regarded as a setting event for other developmental transitions in infancy with important implications for socioemotional development and parent–child interaction. Using an age‐held‐constant design, this study examined changes in reported infant behaviour and maternal proactive/reactive control and compared them with direct observations of infant and maternal behaviour associated with the development of self‐produced locomotion. Maternal reports were obtained prior to the locomotor transition and, for half the sample, after infants had transitioned to effective mobility. Observations of all infants were conducted shortly after the second interview. Prelocomotor and transitioning infants showed none of the expected behavioural differences (e.g. emotionality and compliance) associated with the locomotor transition. There was modest confirmation of expected differences in maternal behaviour, particularly in the use of reactive control techniques, and mothers of transitioning infants showed higher proactive controls before their infants began to crawl. These findings suggest that the changes in parent–child interaction associated with the locomotor transition may have as much to do with parental expectations than with changes in infant socioemotional behaviour. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
233.
Stem cell research has important implications for medicine. The source of stem cells influences their therapeutic potential, with stem cells derived from early-stage embryos remaining the most versatile. Somatic cell nuclear transfer (SCNT), a source of embryonic stem cells, allows for understandings about disease development and, more importantly, the ability to yield embryonic stem cell lines that are genetically matched to the somatic cell donor. However, SCNT requires women to donate eggs, which involves injection of ovulation-inducing hormones and egg retrieval through laparoscopy or transvaginal needle aspiration. Risks from this procedure are fiercely debated, most notably risk of ovarian hyperstimulation syndrome (OHSS). This review examines risk of OHSS resulting from oocyte donation. We conclude that risk posed by OHSS in egg donation is not significant enough to warrant undue concern, and much of this can be eliminated when proper precautions are taken. This bears relevance to the future of stem cell research policymaking.  相似文献   
234.
This study examined neural features of emotional responses to errors. We specifically examined whether directed emotion regulation of negative emotion associated with error modulates action-monitoring functions of anterior cingulate cortex, including conflict monitoring, error processing, and error prevention. Seventeen healthy adults performed a continuous performance task during assessment by fMRI. In each block, participants were asked either to increase or decrease their negative emotional responses or to react naturally after error commission. Emotion regulation instructions were associated with modulation of rostral and dorsal anterior activity and of their effective connectivity following errors and conflict. Cingulate activity and connectivity predicted subsequent errors. These data may suggest that responses to errors are affected by emotion and that aspects of emotion and cognition are inextricably linked, even during a nominally cognitive task.  相似文献   
235.
Although linguistic traditions of the last century assumed that there is no link between sound and meaning (i.e., arbitrariness), recent research has established a nonarbitrary relation between sound and meaning (i.e., sound symbolism). For example, some sounds (e.g., /u/ as in took) suggest bigness whereas others (e.g., /i/ as in tiny) suggest smallness. We tested whether sound symbolism only marks contrasts (e.g., small versus big things) or whether it marks object properties in a graded manner (e.g., small, medium, and large things). In two experiments, participants viewed novel objects (i.e., greebles) of varying size and chose the most appropriate name for each object from a list of visually or auditorily presented nonwords that varied incrementally in the number of "large" and "small" phonemes. For instance, "wodolo" contains all large-sounding phonemes, whereas "kitete" contains all small-sounding phonemes. Participants' choices revealed a graded relationship between sound and size: The size of the object linearly predicted the number of large-sounding phonemes in its preferred name. That is, small, medium, and large objects elicited names with increasing numbers of large-sounding phonemes. The results are discussed in relation to cross-modal processing, gesture, and vocal pitch.  相似文献   
236.
Traditionally, characterizations of the macrolevel functional organization of the human cerebral cortex have focused on the left and right cerebral hemispheres. However, the idea of left brain versus right brain functions has been shown to be an oversimplification. We argue here that a top-bottom divide, rather than a left-right divide, is a more fruitful way to organize human cortical brain functions. However, current characterizations of the functions of the dorsal (top) and ventral (bottom) systems have rested on dichotomies, namely where versus what and how versus what. We propose that characterizing information-processing systems leads to a better macrolevel organization of cortical function; specifically, we hypothesize that the dorsal system is driven by expectations and processes sequences, relations, and movement, whereas the ventral system categorizes stimuli in parallel, focuses on individual events, and processes object properties (such as shape in vision and pitch in audition). To test this hypothesis, we reviewed over 100 relevant studies in the human neuroimaging and neuropsychological literatures and coded them relative to 11 variables, some of which characterized our hypothesis and some of which characterized the previous dichotomies. The results of forward stepwise logistic regressions supported our characterization of the 2 systems and showed that this model predicted the empirical findings better than either the traditional dichotomies or a left-right difference.  相似文献   
237.
Background. Many countries rely on immigrants for population growth and to maintain a skilled workforce. However, many such immigrants face literacy‐related barriers to success in education and in the labour force. Aims. This meta‐analysis reviews experimental and quasi‐experimental studies to examine strategies for teaching English literacy to immigrant students. Method. Following an exhaustive and systematic search for studies meeting pre‐determined inclusion criteria, two researchers independently extracted data from 26 English as a Second Language (ESL) studies involving 3,150 participants. These participants consisted of ESL immigrant students in kindergarten through grade 6 who were exposed to English literacy instructional interventions. Measured outcomes were reading and writing. Results and Conclusions. Mean effect sizes vary from small to large, depending on instructional interventions and outcome constructs. Across several different grade levels, settings, and methodological features, pedagogical strategies used in teaching ESL to immigrant students are associated with increased competence in reading and writing. Collaborative reading interventions, in which peers engage in oral interaction and cooperatively negotiate meaning and a shared understanding of texts, produced larger effects than systematic phonics instruction and multimedia‐assisted reading interventions. The results show that the pedagogical strategies examined in this meta‐analysis produced statistically significant benefits for students in all grade levels. The findings also show that students from low socio‐economic status (SES) background benefit from ESL literacy interventions. However, significant heterogeneity was found in each subset. Educators and policy makers are encouraged to consider specific school contexts when making decisions about optimal pedagogical strategies. It is possible that contextual factors as well as ESL learner characteristics may influence the effectiveness of these strategies. To ensure literacy acquisition for immigrant students whose primary language is not English, it is important to continue to research successful literacy practices in ways that better inform educators and policy makers.  相似文献   
238.
We observed 11 undergraduates in an experiment designed to simulate infant caregiving. In negative reinforcement conditions experienced by all participants, a targeted caregiving response (e.g., rocking a baby doll) produced escape from, and avoidance of, a recorded infant cry. Nine participants' caregiving was shown to be controlled by this negative reinforcement contingency. Nine participants experienced an extinction condition that consisted of an inescapable cry, and the previously reinforced caregiving responses of 2 of these participants were resistant to extinction. For both of these participants, the previously reinforced response was eliminated when an alternative form of caregiving was reinforced. These results highlight the role of negative reinforcement in infant caregiving and suggest the need for additional research on the effects of crying on caregivers as well as the development of effective strategies for minimizing infant crying.  相似文献   
239.
240.
This study examined attitudes about body image and racial identity among Black women at a predominately White college in the United States. We conducted in-depth qualitative interviews with 34 women about their school experiences, family, racial identity, self-esteem, and body image. We found that early childhood influences including family and school environment had profound impacts on their racial identity and body image. Through a qualitative analysis based in grounded theory, we found that participants’ identification with White and/or Black culture produced levels of body satisfaction and a set of beauty ideals that generally corresponded to four racial identity groups: identification with White or Black culture, floating between both, or having a diverse self-identity.  相似文献   
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