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11.
These recommendations describe the minimum standard criteria for genetic counseling and testing of individuals and families with fragile X syndrome, as well as carriers and potential carriers of a fragile X mutation. The original guidelines (published in 2000) have been revised, replacing a stratified pre- and full mutation model of fragile X syndrome with one based on a continuum of gene effects across the full spectrum of FMR1 CGG trinucleotide repeat expansion. This document reviews the molecular genetics of fragile X syndrome, clinical phenotype (including the spectrum of premature ovarian failure and fragile X-associated tremor-ataxia syndrome), indications for genetic testing and interpretation of results, risks of transmission, family planning options, psychosocial issues, and references for professional and patient resources. These recommendations are the opinions of a multicenter working group of genetic counselors with expertise in fragile X syndrome genetic counseling, and they are based on clinical experience, review of pertinent English language articles, and reports of expert committees. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. The professional judgment of a health care provider, familiar with the facts and circumstances of a specific case, will always supersede these recommendations.  相似文献   
12.
The privacy of patients is jeopardised when medical records and data are spread or shared beyond the protected cloud of institutions. This is because breaches force them to the brink that they start abstaining from full disclosure of their condition. This type of condition has a negative effect on scientific research, patients and all stakeholders. A blockchain-based data sharing system is proposed to tackle this issue, which employs immutability and autonomy properties of the blockchain to sufficiently resolve challenges associated with access control and handle sensitive data. Our proposed system is supported by a Discrete Wavelet Transform to enhance the overall security, and a Genetic Algorithm technique to optimise the queuing optimization technique as well. Introducing this cryptographic key generator enhances the immunity and system access control, which allows verifying users securely in a fast way. This design allows further accountability since all users involved are already known and the blockchain records a log of their actions. Only when the users’ cryptographic keys and identities are confirmed, the system allows requesting data from the shared queuing requests. The achieved execution time per node, confirmation time per node and robust index for block number of 0.19 s, 0.17 s and 20 respectively that based on system evaluation illustrates that our system is robust, efficient, immune and scalable.  相似文献   
13.
From the perspective of virtue ethics, is it possible and permissible to enhance moral behavior through gene modification? In preparation to answer this question, we must ask five questions: (1) What may we assume regarding genetic inheritance and human nature? (2) Can specific genes predispose behavior related to the moral virtues? (3) What kind of genetic enhancement would be useful for moral enhancement? (4) Should there be a distinction between somatic and germline gene modification? (5) Is genetic modification best approach to moral enhancement? This article concedes that genetic engineering has the capacity to enhance the human disposition to moral behavior, but gene editing cannot create virtue because virtues are stable, habituated dispositions, acquired over time. That being said, gene editing for purposes of enhancing moral behavior is permissible.  相似文献   
14.
When in a negative mood state, individuals with major depressive disorder (MDD) may have difficulties recalling positive autobiographical memories in a manner that repairs that negative mood. Using cognitive bias modification techniques, investigators have successfully altered different aspects of cognition among individuals with MDD. However, little has been done to investigate the modification of positive autobiographical memory recall. This study examined the impact of a novel positive memory enhancement training (PMET) on the memories and subjective affective experiences of individuals with MDD (N = 27). Across a series of trials, participants first recalled a sad memory to elicit a negative mood state. They then recalled a happy memory and completed procedures to elicit a vivid, here-and-now quality of the memory. PMET procedures were hypothesized to promote mood repair via the recall of increasingly vivid and specific positive memories. PMET participants demonstrated improved memory specificity and greater perceived ability to “relive” positive memories. The procedures also repaired mood; PMET participants’ affect following recall of positive memories did not differ from control participants’ affect following recall of neutral memories. Results provide preliminary support for PMET as a method to improve the quality of positive memories and facilitate emotion regulation in MDD.  相似文献   
15.
Attention bias modification (ABM) aimed at correcting dysfunctional biases in anxiety patients has met with only mild success. Inspired by recent studies showing large effects of financial reward upon attention shifts, we contrasted effects of traditional dot-probe ABM and reward upon attention biases in a between-subject 2 × 2 design. Twenty-seven participants in group cognitive behavioural therapy (GCBT) for social anxiety disorder (SAD) were randomly assigned to undergo six sessions of a dot-probe task consisting of ABM or placebo ABM along with random or high reward following neutral stimuli. There was no influence of ABM on participants' attention bias over and above the influence of GCBT. Reward, however, had a strong influence on attention bias. Neither ABM nor reward reduced SAD symptoms over and above the effects of GCBT. The results add to the growing evidence that benefits of ABM through dot-probe training are unreliable but suggest on the other hand that rewarding attention may strongly influence dysfunctional attention biases.  相似文献   
16.
Previous observations of a New Caledonian crow (Corvus moneduloides) spontaneously bending wire and using it as a hook [Weir et al. (2002) Science 297:981] have prompted questions about the extent to which these animals 'understand' the physical causality involved in how hooks work and how to make them. To approach this issue we examine how the same subject ("Betty") performed in three experiments with novel material, which needed to be either bent or unbent in order to function to retrieve food. These tasks exclude the possibility of success by repetition of patterns of movement similar to those employed before. Betty quickly developed novel techniques to bend the material, and appropriately modified it on four of five trials when unbending was required. She did not mechanically apply a previously learned set of movements to the new situations, and instead sought new solutions to each problem. However, the details of her behaviour preclude concluding definitely that she understood and planned her actions: in some cases she probed with the unmodified tools before modifying them, or attempted to use the unmodified (unsuitable) end of the tool after modification. Gauging New Caledonian crows' level of understanding is not yet possible, but the observed behaviour is consistent with a partial understanding of physical tasks at a level that exceeds that previously attained by any other non-human subject, including apes.  相似文献   
17.
This study investigated whether facilitating a benign interpretive bias decreases negative thought intrusions in generalized anxiety disorder (GAD). Clients were randomly allocated to an interpretation modification condition in which they repeatedly accessed benign meanings of emotionally ambiguous homographs and scenarios, or to a control condition in which they accessed threat and benign meanings with equal frequency. Worry frequency was assessed using a breathing focus task that involved categorising the valence of thought intrusions before and after an instructed worry period. Interpretation bias was assessed during the modification tasks, and on a different measure of interpretation bias (sentence completion) following a period of worry. The experimental procedure modified interpretations made during training, and in the later sentence completion task. Furthermore, compared to the control group, the benign group showed fewer negative thought intrusions during breathing focus (as rated by both participants and an assessor). These findings show that it is possible to induce a more benign interpretive bias in GAD clients and that this reduces negative thought intrusions.  相似文献   
18.
In this experiment we investigated the effect of different instructions on the modification of attentional biases, and subsequently on worry persistence. Participants without excessive worry completed a modified dot-probe task, designed to train attention either to threat or neutral words. Half of each group was given explicit instructions regarding the relationship between word valence and target location, and half were given the more usual minimal instructions. Impact on worry persistence was assessed by categorizing the valence of thought intrusions before and after a period of instructed worry. Response latencies to test items on the dot-probe task showed that attention had been successfully manipulated in the expected direction, and explicit instructions led to more effective attention modification. Moreover, participants in the attend-threat group who received explicit instructions reported significantly more negative thought intrusions following instructed worry, as rated by an assessor, whereas participants in the attend-neutral group did not. These findings suggest that an attentional bias towards threatening information plays a role in worry persistence, and that explicit instructions may be helpful in modifying this bias.  相似文献   
19.
期望反应模式是认知诊断分类的类中心,确定了诊断范围中属性及其层级关系后,类中心的数目由测验Q矩阵决定.类中心应该是完备的,即理论上有多少个知识状态就应该有多少个类中心,这涉及评分方式、Q矩阵设计、Q矩阵评价与修改、认知诊断测验如何实施等问题的讨论.重点给出多级评分认知诊断测验不同属性层级对应的完备Q矩阵设计的例子和罗列了Wang等人(2013)的Q矩阵修改的方法.  相似文献   
20.
This paper argues for culture as a significant determinant of the modern human genome. As progress in the fields of genetics and evolutionary biology have gained greater insights into evolutionary process, aspects of classical proposals explaining how phenotypic responses to environmental experience could make their way into the genotype have returned in new guises. Recent proposals recognize environmental context as a key source of genetic variation by directly altering selection pressures to mask and unmask adaptive value of expressed traits, by reorganizing the combination and expression of genes during ontogeny to provide novel variants for selection, and by influencing developmental trajectories through epigenetic systems acutely sensitive to ontogenetic contexts. The emergence of a robust human socio-cultural niche, shielding humans from more proximate evolutionary pressures that marked our ancestral evolution, has arguably provided the strongest directive force on modern human evolution. Language is discussed as an exemplar of a cultural niche with a powerful self-organizing dynamic and the potential to dramatically alter the human genome.  相似文献   
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