Factors affecting the correlation coefficient template matching algorithm with application to real-time 2-D coronary artery MR imaging

This paper characterizes factors affecting the accuracy of the correlation coefficient (CC) template matching algorithm, as applied to motion tracking from two-dimensional real-time coronary artery magnetic resonance images. The performance of this algorithm is analyzed in the presence of both random and systematic error. In the presence of random error, it is shown that a necessary and sufficient condition for accurate motion tracking is a large CC difference-to-noise ratio (CCDNR). The CCDNR itself is in turn affected by five factors: image and template size, image and template structure, and the magnitude of the noise. Techniques are introduced for manipulating some of these factors in order to increase the CCDNR for greater motion tracking accuracy. In the presence of superimposed systematic error it is shown that, while large CCDNR is necessary, it alone is not sufficient to ensure accurate motion tracking. Techniques are developed for improving motion tracking accuracy that minimize the effects of systematic error, while maintaining an adequate CCDNR level. The ability of these techniques to improve motion tracking accuracy is demonstrated both in phantoms and in coronary artery images.     

The influence of depressive symptoms on experimental smoking and intention to smoke in a diverse youth sample.

Numerous studies have shown associations between smoking and depression, but the generalizability of the relationship across ethnic groups remains unknown. The present study assessed the association between depression and smoking intention and experimentation among adolescents from four ethnic groups in the Los Angeles area-Chinese/Chinese American, Latino/Hispanic, Persian/Iranian, and White. Over 800 7th graders in the Los Angeles area completed measures of depressive symptoms, experimentation with smoking, intention to smoke, and sociodemographic covariates. Chinese/Chinese American students had the lowest levels of depressive symptoms, whereas Latinos/Hispanics had the highest levels. Latinos/Hispanics also were the most likely to intend to smoke in the next year and were the most likely to have started experimenting with cigarette smoking. Depressive symptoms were significantly associated with intention to smoke even after controlling for language use acculturation, socioeconomic status, gender, and ethnicity. The association between depressive symptoms and intention to smoke did not vary significantly across ethnic groups. These results indicate that the association between depressive symptoms and adolescent smoking generalizes across diverse ethnic groups.     

Ultrafine Particle Deposition in a Human Tracheobronchial Cast

The deposition of 0.20, 0.15, and 0.04 μm diameter particles was measured in a human central airway cast using a variable larynx with cyclic inspiratory flow. Data were compared with theoretical predictions for deposition from laminar flow for the first seven airway generations. With the exception of tracheal deposition, which on average exceeded predictions by a factor of 9, the measured deposition was about twice that predicted. The enhanced deposition is attributable to secondary swirling flows. Less enhancement is observed at higher inspiratory flow rates as turbulence increases. The surface density of particles deposited at bifurcations was approximately 20% greater than along the airway lengths. This increased deposition at bifurcations should be considered when calculating tissue dose for particles which act before the initial deposit is removed by clearance processes.     

Vaccine genotype and route of administration affect pseudorabies field virus latency load after challenge

The influence of vaccine genotype and route of administration on the efficacy of pseudorabies virus (PRV) vaccines against virulent PRV challenge was evaluated in a controlled experiment using five genotypically distinct modified live vaccines (MLVs) for PRV. Several of these MLVs share deletions in specific genes, however, each has its deletion in a different locus within that gene. Pigs were vaccinated with each vaccine, either via the intramuscular or intranasal route, and subsequently challenged with a highly virulent PRV field strain. During a 2-week period following challenge with virulent PRV, each of the vaccine strains used in this study was evaluated for its effectiveness in the reduction of clinical signs, prevention of growth retardation and virulent virus shedding. One month after challenge, tissues were collected and analyzed for virulent PRV latency load by a recently developed method for the electrochemiluminescent quantitation of latent herpesvirus DNA in animal tissues after PCR amplification. It was determined that all vaccination protocols provided protection against clinical signs resulting from field virus challenge and reduced both field virus shedding and latency load after field virus challenge. Our results indicated that vaccine efficacy was significantly influenced by the modified live vaccine strain and route of administration. Compared to unvaccinated pigs, vaccination reduced field virus latency load in trigeminal ganglia, but significant differences were found between vaccines and routes of administration. We conclude that vaccine genotype plays a role in the effectiveness of PRV MLVs.     

Nicotine patch and paroxetine for smoking cessation.

Smokers (N?=?224) were randomized to 1 of 3 groups: (a) transdermal system (TNS) + placebo; (b) TNS + paroxetine (20 mg); (c) TNS + paroxetine (40 mg). Assignment to treatment was double-blind. Nicotine patch (TNS) treatment was provided for 8 weeks; paroxetine or placebo was provided for 9 weeks. Abstinence rates at Weeks 4, 10, and 26 were as follows: (a) TNS + placebo: 45%, 36%, and 25%; (b) TNS + paroxetine (20 mg): 48%, 33%, and 21 %; (c) TNS + paroxetine (40 mg): 57%, 39%, and 27%. The differences were not statistically significant. The combined treatment was more effective in reducing both craving and depression symptoms associated with smoking cessation. A subgroup analysis comparing compliant participants was also conducted. Abstinence rates at Weeks 4, 10, and 26 were as follows: (a) TNS + placebo: 46%, 35%, and 24%; (b) TNS + paroxetine (20 mg): 64%, 43%, and 33%; (c) TNS + paroxetine (40 mg): 74%, 51%, and 38%. The differences between paroxetine groups and placebo at Week 4 were statistically significant. Although paroxetine may add value to the current standard of care in excess of potential risk, more conclusive evidence is needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

What the tongue tells the brain.

Review of the literature indicates that speech is controlled by an intricate closed-loop feedback system. To bring about feedback control of the speech musculature, the higher neural centers should be kept constantly aware of (a) spatial position, (b) direction of movement, and (c) rate of movement of the articulators. The feedback mechanisms existing within the tongue that can mediate such dynamic space-time information are described. The unique 3-dimensional arrangement of the lingual muscle-spindle network is structurally organized to operate as a built-in geometric reference system. This network is capable of signaling higher brain centers as to the changing length, position, and rate of movement of the tongue during the articulatory motions of human speech. The short-latency, cervical dorsal root pathway conducting hypoglossal afferent information is described as well as the cortical projections of this complex rapidly-acting feedback system. The implications of these neurophysiological findings support a phonetic target-oriented theory of speech production. Neural receptors provide essential information regarding the moment-to-moment state of the speech system so that relatively invariant ends can be achieved despite the mechanical phonetic variability characterizing coarticulation. (58 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Validity of alternative self-report indices of smoking among adolescents.

The convergent validity of popularly used open-ended and closed-ended self-report measures of smoking was examined. Carbon monoxide (CO) samples were obtained from 11th-grade Canadian students as an independent method of assessing recent smoking. In addition to CO, 5 known psychosocial correlates of smoking (attitude, subjective norm, risk taking, best friend's smoking, and other friends' smoking) were used to estimate convergence with the self-report smoking indices. Results indicate that both simple closed-ended scales, with only a few response options, and more continuous, open-ended measures performed about equally as well as correlates of CO and the psychosocial measures, but only if the open-ended scales were subjected to a normalizing transformation to optimize their convergence. After this transformation was performed, convergence depended more on the time-span covered by the self-report indices than on the open-ended/closed-ended distinction. Implications of these results for different assessment goals were discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age, socioeconomic status, severity of mental disorder, and chronicity as predictors of physical attractiveness.

The relations of age, SES, race, 3 indexes of chronicity, and 3 indexes of severity of disorder with physical attractiveness were examined in 43 13–66 yr old female psychiatric patients to test whether demographic variables mediate relations found between physical attractiveness and clinical variables. A correlation analysis found only time since 1st breakdown, age, and SES to be significantly related to attractiveness at a multivariate .05 level. A partial correlation analysis showed that age mediated the relation found between time since 1st breakdown and attractiveness, but not the relation between SES and attractiveness. Findings suggest that demographic variables are strongly related to attractiveness and may account for apparent relations found between attractiveness and clinical variables. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tobacco use moderates the association between major depression and obesity.

Objective: Based on a maladaptive coping explanation, the relationship between major depression (MD) and obesity could be strong among nonsmokers, who may engage in unhealthy eating and sedentary behavior to cope with depression. By contrast, the MD-obesity association could be weak among smokers, who can use tobacco (instead of food or sedentary behavior) to cope with mood symptoms. This study examined smoking status and tobacco dependence as moderators of the MD-obesity link. Design: Correlational, cross-sectional population-based survey of 41,654 U.S. adults. Main Outcome Measures: Obesity (body mass index [BMI] ≥30 kg/m2) and quantitative BMI value. Results: Current smoking status moderated the association between past-year MD and current obesity, as well as the link between MD and BMI value (ps ≤ .0001). MD predicted obesity and BMI among nonsmokers (ps ps ≥ .10). Similar findings emerged with tobacco dependence as the moderator. Each finding persisted after accounting for demographics, psychiatric variables, and potential confounds. Conclusion: Tobacco use characteristics appear to moderate the MD-obesity association in the U.S. population. These findings may shed light on the mechanisms linking MD and obesity and have implications for identifying which individuals may benefit most from obesity interventions that target depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

You're only as pretty as you feel: Facial expression as a determinant of physical attractiveness.

In Exp I, photos of 15 female target persons posing happy, neutral, and sad facial expressions were rated by 257 undergraduates for facial attractiveness using paired comparisons and Likert scales. Half of the raters were instructed to compensate for the effects of facial expression. Paired comparisons and Likert ratings were highly correlated. Target persons were less attractive when posing sad expressions than when posing neutral or happy expressions, which did not differ. In addition, independent ratings of 4 dimensions of the target persons' facial expression were obtained: pleasantness, surprise, intensity, and naturalness. Changes in these dimensions from the neutral to the happy and sad expressions and the corresponding changes in attractiveness were consistently related only to pleasantness, supporting the reinforcement-affect theory of attraction. Exp II, with 21 male undergraduates, related overall attractiveness to facial and bodily attractiveness. Both facial and bodily attractiveness were predictive of overall attractiveness, but the face was a slightly more powerful predictor. Results are discussed with respect to the stability of physical attractiveness, and alternative explanations of the mental-illness/physical-unattractiveness relation are proposed. (54 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)