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Whereas there is evidence that interpersonal communication, or conversation, influences predictors of alcohol consumption, the role of involvement in conversation effects remains unclear. This study explored how three aspects of involvement (topical relevance, or how relevant the topic of alcohol is; conversational relevance, or how relevant a conversation about alcohol is; and conversational effort, or how much effort people put into such a conversation), influence conversation effects. After assessing topical relevance, 46 same-sex dyads were requested to talk about the negative consequences of heavy drinking. Within each dyad, one participant was asked to take on an active talking role and the other participant a passive listening role. Next, conversational relevance, effort, and predictors of heavy drinking were measured. Results showed that participants who drank more alcohol found the topic of heavy drinking more relevant. This topical relevance increased conversational relevance and conversational effort. Conversational effort further increased when a talking role was assigned. Furthermore, participants who put more effort in the conversation and found it more relevant had more positive norms, identified more strongly with alcohol, and had higher intentions to drink. These findings suggest that more involvement in an alcohol-related conversation does not always lead to desirable outcomes.  相似文献   
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Magnetic field generated by neuronal activity could alter magnetic resonance imaging (MRI) signals but detection of such signal is under debate. Previous researches proposed that magnitude signal change is below current detectable level, but phase signal change (PSC) may be measurable with current MRI systems. Optimal imaging parameters like echo time, voxel size and external field direction, could increase the probability of detection of this small signal change. We simulate a voxel of cortical column to determine effect of such parameters on PSC signal. We extended a laminar network model for somatosensory cortex to find neuronal current in each segment of pyramidal neurons (PN). 60,000 PNs of simulated network were positioned randomly in a voxel. Biot–savart law applied to calculate neuronal magnetic field and additional phase. The procedure repeated for eleven neuronal arrangements in the voxel. PSC signal variation with the echo time and voxel size was assessed. The simulated results show that PSC signal increases with echo time, especially 100/80 ms after stimulus for gradient echo/spin echo sequence. It can be up to 0.1 mrad for echo time = 175 ms and voxel size = 1.48 × 1.48 × 2.18 mm3. With echo time less than 25 ms after stimulus, it was just acquired effects of physiological noise on PSC signal. The absolute value of the signal increased with decrease of voxel size, but its components had complex variation. External field orthogonal to local surface of cortex maximizes the signal. Expected PSC signal for tactile detection in the somatosensory cortex increase with echo time and have no oscillation.  相似文献   
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Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  相似文献   
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