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231.
Mosaic chromosomal abnormalities are relatively common. However, mosaicism may be missed due to multiple factors including failure to recognize clinical indications and order appropriate testing, technical limitations of diagnostic assays, or sampling tissue (s) in which mosaicism is either not present, or present at very low levels. Blood leukocytes have long been the “gold standard” sample for cytogenetic analysis; however, the culturing process for routine chromosome analysis can complicate detection of mosaicism since the normal cell line may have a growth advantage in culture, or may not be present in the cells that produce metaphases (the lymphocytes). Buccal cells are becoming increasingly utilized for clinical analyses and are proving to have many advantages. Buccal swabs allow for simple and noninvasive DNA collection. When coupled with a chromosomal microarray that contains single nucleotide polymorphic probes, analysis of buccal cells can maximize a clinician’s opportunity to detect cytogenetic mosaicism. We present three cases of improved diagnosis of mosaic aberrations using buccal specimens for chromosomal microarray analysis. In each case, the aberration was either undetectable in blood or present at such a low level it likely could have gone undetected. These cases highlight the limitations of certain laboratory methodologies for identifying mosaicism. We also present practice implications for genetic counselors, including clinic workflow changes and counseling approaches based on increasing use of buccal samples.  相似文献   
232.
Recent research has determined that word meanings can instantly influence the meaning and distribution of other words in the sentence. Here, we manipulated basic carrier sentences with the disjunction or linking two nouns that were either filling the same thematic role or not, and were either semantically related or not. Though previous research has shown that one word can prime a semantically related word even in a sentential context, we predicted that if or cues knowledge about contextually‐relevant alternatives, priming for semantic relatives will only obtain when those words also fill the same thematic role. These predictions were confirmed, as self‐paced reading times of the second alternative in the sentence were faster only when the two alternatives shared the same thematic role and semantic category, suggesting that disjunction words like or function similarly to verbs, which cue knowledge about expected argument structure and sense depending on sentential context. The relevance of these findings for basic reasoning phenomena (i.e., the subadditivity effect) is also discussed.  相似文献   
233.
We examine a distinctive kind of problem for decision theory, involving what we call discontinuity at infinity. Roughly, it arises when an infinite sequence of choices, each apparently sanctioned by plausible principles, converges to a ‘limit choice’ whose utility is much lower than the limit approached by the utilities of the choices in the sequence. We give examples of this phenomenon, focusing on Arntzenius et al.’s Satan’s apple, and give a general characterization of it. In these examples, repeated dominance reasoning (a paradigm of rationality) apparently gives rise to a situation closely analogous to having intransitive preferences (a paradigm of irrationality). Indeed, the agents in these examples are vulnerable to a money pump set-up despite having preferences that exhibit no obvious defect of rationality. We explore several putative solutions to such problems, particularly those that appeal to binding and to deliberative dynamics. We consider the prospects for these solutions, concluding that if they fail, the examples show that money pump arguments are invalid.  相似文献   
234.
Determining how we use our body to support cognition represents an important part of understanding the embodied and embedded nature of cognition. In the present investigation, we pursue this question in the context of a common perceptual task. Specifically, we report a series of experiments investigating head tilt (i.e., external normalization) as a strategy in letter naming and reading stimuli that are upright or rotated. We demonstrate that the frequency of this natural behavior is modulated by the cost of stimulus rotation on performance. In addition, we demonstrate that external normalization can benefit performance. All of the results are consistent with the notion that external normalization represents a form of cognitive offloading and that effort is an important factor in the decision to adopt an internal or external strategy.  相似文献   
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236.
The importance of having ethical oversight in research that is carried out on humans is well established. Research ethics, which is mainly influenced by a biomedical ethical framework, aims to ensure that the well-being and the rights of research participants are upheld and that any potential risks and harms are reduced. However, research is also considered to be a social activity with social effects. Therefore the principles of Catholic Social Teaching as a framework for research ethics may be significant. This paper outlines those principles and demonstrates how these principles may be used for: (1) reflecting ethically on research (i.e. before the project begins), (2) judging a research ethics proposal (i.e. the ethical review) and (3) providing guidelines for action in research (i.e. the implementation of the research project).  相似文献   
237.
Researchers have investigated visual search behavior for almost a century. During that time, few studies have examined the cognitive processes involved in hiding items rather than finding them. To investigate this, we developed a paradigm that allowed participants to indicate where they would hide (or find) an item that was to be found (or hidden) by a friend or a foe. We found that (i) for friends more than foes, participants selected the pop-out item in the display, and (ii) when the display was homogeneous, they selected nearby and corner items. These behaviors held for both hiding and finding, although hide and find behaviors were not identical. For pop-out displays, decision times were unusually long when hiding an item from a foe. These data converge on the conclusion that the principles of search and concealment are similar, but not the same. They also suggest that this paradigm will provide researchers a powerful method for investigating theory of mind in adults.  相似文献   
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239.
The field of couple and relationship education is dominated by a focus on helping committed couples strengthen their relationship. This article reviews several lines of research to argue that the field should give greater priority to youth relationship education—individually oriented relationship literacy education for adolescents and young adults. Serious problems are common in adolescent and young adult romantic relationships and increasing numbers of youth follow paths from adolescence to marriage that make it harder for them to form and sustain a healthy marriage. Early evidence on the effectiveness of individually oriented youth relationship education provides some reason for optimism. The article concludes by exploring implications of this proposed shift in the field for practice and policy.  相似文献   
240.
An ongoing debate in political psychology is about whether small wording differences have outsized behavioral effects. A leading example is whether subtle linguistic cues embedded in voter mobilization messages dramatically increase turnout. An initial study analyzing two small‐scale field experiments argued that describing someone as a voter (noun) instead of one who votes (verb) increases turnout rates 11 to 14 points because the noun activates a person's social identity as a voter. A subsequent study analyzing a large‐scale field experiment challenged this claim and found no effect. But questions about the initial claim's domain of applicability persist. The subsequent study may not have reproduced the conditions necessary for the psychological phenomenon to occur, specifically the electoral contexts were not competitive or important enough for the social identity to matter. To address the first of these critiques, as well as other potential explanations for different results between the first two studies, we conduct a large‐scale replication field experiment. We find no evidence that this minor wording change increases turnout levels. This research provides new evidence that the strategy of invoking the self does not appear to consistently increase turnout and calls into question whether subtle linguistic cues have outsized behavioral effects.  相似文献   
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