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This article describes early stages in the acquisition of a first vocabulary by infants and young children. It distinguishes two major stages, the first of which operates by a stand‐alone word‐to‐world pairing procedure and the second of which, using the evidence so acquired, builds a domain‐specific syntax‐sensitive structure‐to‐world pairing procedure. As we show, the first stage of learning is slow, restricted in character, and to some extent errorful, whereas the second procedure is determinative, rapid, and essentially errorless. Our central claim here is that the early, referentially based learning procedure succeeds at all because it is reined in by attention‐focusing properties of word‐to‐world timing and related indicants of referential intent.  相似文献   
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We recently described a new afimbrial adhesin, AfaE-VIII, produced by animal strains associated with diarrhea and septicemia and by human isolates associated with extraintestinal infections. Here, we report that the afa-8 operon, encoding AfaE-VIII adhesin, from the human blood isolate Escherichia coli AL862 is carried by a 61-kb genomic region with characteristics typical of a pathogenicity island (PAI), including a size larger than 10 kb, the presence of an integrase-encoding gene, the insertion into a tRNA locus (pheR), and the presence of a small direct repeat at each extremity. Moreover, the G+C content of the afa-8 operon (46.4%) is lower than that of the E. coli K-12/MG1655 chromosome (50.8%). Within this PAI, designated PAI I(AL862), we identified open reading frames able to code for products similar to proteins involved in sugar utilization. Four probes spanning these sequences hybridized with 74.3% of pathogenic afa-8-positive E. coli strains isolated from humans and animals, 25% of human pathogenic afa-8-negative E. coli strains, and only 8% of fecal strains (P = 0.05), indicating that these sequences are strongly associated with the afa-8 operon and that this genetic association may define a PAI widely distributed among human and animal afa-8-positive strains. One of the distinctive features of this study is that E. coli AL862 also carries another afa-8-containing PAI (PAI II(AL862)), which appeared to be similar in size and genetic organization to PAI I(AL862) and was inserted into the pheV gene. We investigated the insertion sites of afa-8-containing PAI in human and bovine pathogenic E. coli strains and found that this PAI preferentially inserted into the pheV gene.  相似文献   
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Although the rising incidence of breast cancer has prompted a surge of intervention strategies aimed at increasing women's use of mammography screening, the majority of patient-directed interventions have not been driven by relevant theoretical work on persuasive health communication. The authors evaluated an intervention derived from prospect theory that was designed to increase women's adherence to recommendations for annual mammography screening. They sent 1 of 3 reminder letters (positive frame, negative frame, or standard hospital prompt) to 929 randomly selected women who were due for mammography screening and had been identified as having either a positive or negative family history of breast cancer. The primary hypothesis that women with a positive history would be more responsive to negatively framed messages, whereas women with a negative history would be more responsive to positively framed letters, was not confirmed. The lack of support for predictions derived from prospect theory raises important questions about the generalizability of laboratory research to natural settings.  相似文献   
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The success of vaccination programs is contingent upon irrefutable scientific safety data combined with high rates of public acceptance and population coverage. Vaccine hesitancy, characterized by lack of confidence in vaccination and/or complacency about vaccination that may lead to delay or refusal of vaccination despite the availability of services, threatens to undermine the success of coronavirus disease 2019 (COVID-19) vaccination programs. The rapid pace of vaccine development, misinformation in popular and social media, the polarized sociopolitical environment, and the inherent complexities of large-scale vaccination efforts may undermine vaccination confidence and increase complacency about COVID-19 vaccination. Although the experience of recent lethal surges of COVID-19 infections has underscored the value of COVID-19 vaccines, ensuring population uptake of COVID-19 vaccination will require application of multilevel, evidence-based strategies to influence behavior change and address vaccine hesitancy. Recent survey research evaluating public attitudes in the United States toward the COVID-19 vaccine reveals substantial vaccine hesitancy. Building upon efforts at the policy and community level to ensure population access to COVID-19 vaccination, a strong health care system response is critical to address vaccine hesitancy. Drawing on the evidence base in social, behavioral, communication, and implementation science, we review, summarize, and encourage use of interpersonal, individual-level, and organizational interventions within clinical organizations to address this critical gap and improve population adoption of COVID-19 vaccination.  相似文献   
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Therapist-report measures of evidence-based interventions have enormous potential utility as quality indicators in routine care; yet, few such tools have shown strong psychometric properties. This study describes reliability and validity characteristics of a therapist-report measure of family therapy techniques for treating adolescent conduct and substance use problems: Inventory of Therapy Techniques for Core Elements of Family Therapy (ITT-CEFT). Study participants included 31 staff therapists treating 68 adolescent clients in eight community-based mental health and substance use clinics. Therapists submitted ITT-CEFT checklists and companion audio recordings for 189 sessions. The ITT-CEFT contains 13 techniques identified as core elements of three manualized family therapy models that are empirically supported for the target group. Therapists also reported on their use of three motivational interventions, and independent observers coded the submitted recordings. ITT-CEFT factor validity was shown via confirmatory factor analyses of the tool’s theoretical structure. Derived modules were: Family Engagement (four items; Cronbach’s α?=?.72); Relational Orientation (five items; α?=?.74); and Interactional Change (four items; α?=?.66). Concurrent validity analyses showed fair-to-excellent therapist reliability compared to observer ratings (ICCs range .64–.75); they showed moderate therapist accuracy compared to observer mean scores, reflecting a tendency to overestimate delivery of the techniques. Discriminant validity analyses showed tool differentiation from motivational interventions. Results offer provisional evidence for the feasibility of using the therapist-report ITT-CEFT to anchor quality procedures for family therapy interventions in real-world settings.

Trial Registration: The parent clinical trial is registered at www.ClinicalTrials.gov, ID: NCT03342872 (registration date: 11.10.17).

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