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1.
OBJECTIVE: Compare the efficacy of a multicomponent social support intervention to standard-of-care counseling on medication adherence among HIV-infected patients initiating antiretroviral therapy. DESIGN: Randomized controlled trial. Generalized estimating equations tested for differences in the percentage of participants achieving 90% adherence. MAIN OUTCOME MEASURES: Pill-taking, electronically monitored over 6 consecutive months; plasma viral load (VL), assessed at 3 and 6 months following initiation of therapy. RESULTS: Of 226 participants who were randomized and began the trial, 87 (38%) were lost to the study by 6 months. The proportion of adherent participants declined steadily over time, with no time by group interaction. Sustained adherence was associated with increased odds of achieving an undetectable VL (OR=1.78; 95% CI=1.01, 3.13). In intention-to-treat analyses, a larger proportion of the intervention group than the control group was adherent (40.15% vs. 27.59%, p=.02) and achieved an undetectable VL p=.04). However, the majority of participants who remained on study experienced some reduction in VL (>or=1-log drop or undetectable), regardless of experimental condition. CONCLUSION: The multicomponent social support intervention significantly improved medication adherence over standard-of-care counseling; evidence for improved virologic outcomes was inconsistent. Early discontinuation of care and treatment may be a greater threat to the health of HIV patients than imperfect medication-taking.  相似文献   
2.
Communication is a multimodal phenomenon. The cognitive mechanisms supporting it are still understudied. We explored a natural dataset of academic lectures to determine how communication modalities are used and coordinated during the presentation of complex information. Using automated and semi‐automated techniques, we extracted and analyzed, from the videos of 30 speakers, measures capturing the dynamics of their body movement, their slide change rate, and various aspects of their speech (speech rate, articulation rate, fundamental frequency, and intensity). There were consistent but statistically subtle patterns in the use of speech rate, articulation rate, intensity, and body motion across the presentation. Principal component analysis also revealed patterns of system‐like covariation among modalities. These findings, although tentative, do suggest that the cognitive system is integrating body, slides, and speech in a coordinated manner during natural language use. Further research is needed to clarify the specific coordination patterns that occur between the different modalities.  相似文献   
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Population attributable risk (PAR) estimates have been used in suicide research to evaluate the impact of psychosocial and socioeconomic risk factors, including affective disorders, traumatic life events, and unemployment. A parallel concept of preventive fraction (PF), allowing for estimation of the impact of protective factors and effectiveness of preventive interventions, is practically unknown in suicidology. The study authors discuss the application of both concepts to suicide research and prevention, and review literature on the subject. Despite several methodological and conceptual limitations, both PAR and PF are valuable instruments to inform development and evaluation of suicide prevention programs.  相似文献   
5.
The preferences of ordinary folks typically display a future‐bias. For instance, we care more about pains and pleasures in our future than pains and pleasures in our past. Indeed, this future‐bias is so pervasive, many have taken it for granted that the preferences of rational agents will, or at least can, display this future‐bias to some degree or other. However, the rationality of future‐biased preferences has recently come in for critique. However, in this article, I offer a defense of future‐biased preferences against three recent attempts – offered by David Brink, Preston Greene and Meghan Sullivan, and Tom Dougherty – to show such preferences irrational.  相似文献   
6.
An eye-tracking experiment investigated whether incremental interpretation applies to interclausal relationships. According to Millis and Just's (1994) delayed-integration hypothesis, interclausal relationships are not computed until the end of the second clause, because the processor needs to have two full propositions before integration can occur. We investigated the processing of causal and diagnostic sentences (Sweetser, 1990; Tversky & Kahneman, 1982) that contained the connective because . Previous research (Traxler, Sanford, Aked, & Moxey, 1997) has demonstrated that readers have greater difficulty processing diagnostic sentences than causal sentences. Our results indicated that difficulty processing diagnostic sentences occurred well before the end of the second clause. Thus comprehenders appear to compute interclausal relationships incrementally.  相似文献   
7.
Cardiovascular reactivity to video game and mental arithmetic stressors was compared among three groups of men: aerobically trained mild hypertensives, untrained mild hypertensives, and a comparison group of untrained normotensives. Relative to the untrained hypertensives, the trained hypertensives reacted to the video game with marginally smaller systolic blood pressure and diastolic blood pressure, but there were no significant differences between these groups in reactivity during the mental arithmetic task. Comparisons between each hypertensive group and the normotensive group showed that blood pressure (BP) reactivity of normotensives during the video game was generally similar to that of trained hypertensives but smaller than that of untrained hypertensives. These results indicate that aerobic training, which has been found to reduce resting BP in mild hypertensives, may also exert a favorable impact in reducing cardiovascular reactivity of hypertensives during some stressful situations.  相似文献   
8.
ABSTRACT The construct validity of assertion was analyzed in three independent correlational studies The convergence of self-reported, laboratory roleplayed, self-observed, and peer-rated measures was examined, as well as their relationship to Norman's peer-rated five personality factors of extraversion, agreeableness, conscientiousness, emotional stability, and culture Twenty-three and 29 undergraduate students participated in Studies 1 and 2, respectively In general, results showed poor convergence among assertiveness measures even when increasing the representativeness and reliability of the role-played laboratory and self-observed measures, as in Study 2 In Study 3, the role-playing test was abandoned and 45 subjects served as peers for one another The results of Study 3 supported the prediction that assertiveness measures showed at least moderate convergence, in addition there were significant relationships between assertiveness and extraversion and between peer-rated assertiveness and agreeableness, conscientiousness, and culture The relative contribution of each assessment procedure to the construct validity of assertion is discussed  相似文献   
9.
Some models of the lexicon predict that recognition of words should produce activation spreading to phonologically related words. Consistent with this prediction, Hillinger (1980) demonstrated priming in a visual lexical decision task for word targets preceded by graphemically similar or graphemically dissimilar primes that rhymed with the target. In Experiment 1, we investigated whether this phonological priming effect occurred automatically or because of subject strategies. Although semantically associated primes produced significant facilitation in Experiment 1, no evidence of phonological priming was obtained. Experiments 2 to 5 were conducted in an attempt to obtain the phonological priming effect. Experiment 5 was a replication of one of Hillinger’s experiments. In none of these experiments was phonological priming observed. These results indicate either that the lexicon is not organized such that spreading activation occurs on the basis of phonological similarity, or that visual lexical decisions are made without phonological mediation.  相似文献   
10.
A pediatric auditory version of the Stroop procedure was developed and administered to 48 normal children from 3 to 6 years of age. Our purpose was to define the developmental course characterizing interaction between auditory and semantic speech dimensions in young children. The procedure was a reaction time (RT) task that required children to respond as quickly and as accurately as possible to words spoken by a male or a female voice. Children were instructed to ignore what was said and to push the "Mommy" button if Mommy was talking or the "Daddy" button if Daddy was talking. Performance was obtained for words with neutral, congruent, and conflicting semantic content. Preschool children manifested processing dependencies that were similar to those observed in adults on the visual Stroop procedure. Conflict between semantic and auditory dimensions significantly increased RT and congruence between the two dimensions significantly decreased RT relative to the neutral condition. The pattern of results indicated that the meaning of words was processed automatically in the normal children. The magnitude of the Stroop effect reflected developmental change with increasing age.  相似文献   
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