A Longitudinal Investigation of the Semantic Receptive-Expressive Gap in Spanish-English Bilingual Children.

Purpose: Although a semantic receptive-expressive gap appears to be a universal feature of early bilingualism, little is known about its development. We sought to determine if the magnitude of the discrepancy between receptive and expressive standard scores changed over time in bilingual children's two languages. Method: In this longitudinal study, standardized receptive and expressive semantics tests of 106 Spanish-English bilingual children with TD were taken at kindergarten and first grade in both English and Spanish. We used a multivariate analysis approach to identify interactions and main effects. Results: Although both receptive and expressive standard scores improved across the year in both languages, the magnitude of the gap was similar for both languages at both time points. However, there was greater improvement in English than in Spanish. Expressive scores at the end of the year were similar to receptive scores a year earlier. Conclusions: The magnitude of this gap remains relatively constant at kindergarten and first grade in both English and Spanish, despite overall improvements in semantic performance in both languages. There is on average roughly a one year lag between receptive and expressive semantics skills. Clinicians should take caution in interpreting receptive-expressive semantic gaps.

Class specific discrimination of volatile organic compounds using a quartz crystal microbalance based multisensor array.

The use of quartz crystal microbalance (QCM) sensor arrays for analyses of volatile organic compounds (VOC) has attracted significant interest in recent years. In this regard, a group of uniformed materials based on organic salts (GUMBOS) has proven to be promising recognition elements in QCM based sensor arrays due to diverse properties afforded by this class of tunable materials. Herein, we examine the application of four novel phthalocyanine based GUMBOS as recognition elements for VOC sensing using a QCM based multisensor array (MSA). These synthesized GUMBOS are composed of copper (II) phthalocyaninetetrasulfonate (CuPcS4) anions coupled with ammonium or phosphonium cations respectively (tetrabutylammonium (TBA), tetrabutylphosphonium (P4444), 3-(dodecyldimethyl-ammonio)propanesulfonate (DDMA), and tributyl-n-octylphosphonium (P4448)). These materials were characterized using ESI-MS and FTIR, while thermal properties were investigated using TGA. Vapor sensing properties of these GUMBOS towards a set of common VOCs at three sample flow rate ratios were examined. Upon exposure to VOCs, each sensor generated analyte specific response patterns that were recorded and analyzed using principal component and discriminant analyses. Use of this MSA allowed discrimination of analytes into different functional group classes (alcohols, chlorohydrocarbons, aromatic hydrocarbons, and hydrocarbons) with 98.6% accuracy. Evaluation of these results provides further insight into the use of phthalocyanine GUMBOS as recognition elements for QCM-based MSAs for VOC discrimination.

Manganese is an additional cation that enhances colonial phase variation of Vibrio vulnificus.

Vibrio vulnificus, an inhabitant of marine and estuarine environments around the world, is the leading cause of reported seafood-related deaths in the United States. Disease is caused by opaque colony-forming strains that produce capsular polysaccharide, loss of which results in an unencapsulated translucent phenotype with diminished virulence potential. Rugose is a third phenotypic variant of V. vulnificus, and produces a separate exopolysaccharide that results in a dry, wrinkled appearance and the ability to form profuse biofilms. Phase variation among these three phenotypes is influenced by several environmental factors, including the presence of calcium in the medium (Garrison-Schilling et al.). In this study, we have identified a second cation, manganese, which substantially increases the propensity of opaque V. vulnificus strains to switch to translucent or rugose phenotypes. In comparative studies, manganese and calcium promoted switching to the same phenotype for some strains but to different phenotypes for others, results of which indicate that the two cations do not always promote the same changes in underlying gene expression. The data here provide further evidence that exposure of V. vulnificus to select cations results in phenotypic changes that impact both virulence capacity and ecology of the organism.

Virtual colorimetric sensor array: single ionic liquid for solvent discrimination.

There is a continuing need to develop high-performance sensors for monitoring organic solvents, primarily due to the environmental impact of such compounds. In this regard, colorimetric sensors have been a subject of intense research for such applications. Herein, we report a unique virtual colorimetric sensor array based on a single ionic liquid (IL) for accurate detection and identification of similar organic solvents and mixtures of such solvents. In this study, we employ eight alcohols and seven binary mixtures of ethanol and methanol as analytes to provide a stringent test for assessing the capabilities of this array. The UV-visible spectra of alcoholic solutions of the IL used in this study show two absorption bands. Interestingly, the ratio of absorbance for these two bands is found to be extremely sensitive to alcohol polarity. A virtual sensor array is created by using four different concentrations of IL sensor, which allowed identification of these analytes with 96.4-100% accuracy. Overall, this virtual sensor array is found to be very promising for discrimination of closely related organic solvents.

Post and during event effect of cell phone talking and texting on driving performance--a driving simulator study.

OBJECTIVE: A number of studies have been done in the field of driver distraction, specifically on the use of cell phone for either conversation or texting while driving. Researchers have focused on the driving performance of drivers when they were actually engaged in the task; that is, during the texting or phone conversation event. However, it is still unknown whether the impact of cell phone usages ceases immediately after the end of task. The primary objective of this article is to analyze the post-event effect of cell phone usage (texting and conversation) in order to verify whether the distracting effect lingers after the actual event has ceased. METHODS: This study utilizes a driving simulator study of 36 participants to test whether a significant decrease in driver performance occurs during cell phone usage and after usage. Surrogate measures used to represent lateral and longitudinal control of the vehicle were standard deviation (SD) of lane position and mean velocity, respectively. RESULTS: RESULTS suggest that there was no significant decrease in driver performance (both lateral and longitudinal control) during and after the cell phone conversation. For the texting event, there were significant decreases in driver performance in both the longitudinal and lateral control of the vehicle during the actual texting task. The diminished longitudinal control ceased immediately after the texting event but the diminished lateral control lingered for an average of 3.38 s. The number of text messages exchanged did not affect the magnitude or duration of the diminished lateral control. CONCLUSION: The result indicates that the distraction and subsequent elevated crash risk of texting while driving linger even after the texting event has ceased. This finding has safety and policy implications in reducing distracted driving.

Cochlear trajectory in pediatric patients.

OBJECTIVES/HYPOTHESIS: As cochlear implantation increases, surgeons are noting possible anatomical differences in pediatric population. Outcome objectives were to study pediatric temporal bone anatomy using high-resolution temporal bone imaging, and analyze the anatomical differences in group 1 (<12 months) versus group 2 (1-4 years) versus group 3 (5-10 years) versus group 4 (10-18 years). STUDY DESIGN: Retrospective chart and radiologic review. METHODS: A retrospective chart and radiologic review of pediatric patients undergoing high-resolution computer tomography of the temporal bones from April 2001 to February 2013 was conducted. Scans were reviewed to record the transmastoid angle and transcanal angle. RESULTS: Seven hundred fifty patients were identified. A total of 1,426 ears were reviewed. The age range was 8 days to 21 years. Of the patients, 57.0% (n = 407) were male. The patients were divided into four groups: group 1 (<12 months), group 2 (1-4 years), group 3 (5-10 years), and group 4 (10-18 years). The transmastoid angle was observed to have variability. Significant differences were observed between groups 2 and 3 (P = .0028) and groups 2 and 4 (P = .0432). Analysis on the transcanal angle was performed. Significant differences existed between age groups 1 and 3 (P = .0150), groups 1 and 4 (P = .0038), and groups 2 and 4 (P = .0358). CONCLUSIONS: Considerable variation exists in pediatric temporal bones. The largest difference in the transmastoid angle was seen in children aged 1 to 4 years. The largest variability in the transcanal angle is between the infant (<12 months) and children >4 years of age. These differences are surgically relevant for round window identification and facial nerve safety during cochlear implant surgery in infants.

Comparison of the validity of four fall-related psychological measures in a community-based falls risk screening.

We examined the measurement properties offall-related psychological instruments with a sample of 133 older adults (M age = 74.4 years, SD = 9.4). Measures included the Comprehensive Falls Risk Screening Instrument, Falls-efficacy Scale-International (FES-I), Activities-specific Balance Confidence (ABC), modified Survey ofActivities and Fear ofFalling in the Elderly (mSAFFE), Consequences of Falling (CoF), Physical Activity Scale for the Elderly (PASE), and 36-Item Short-Form Health Survey (SF-36). The FES-I, ABC, mSAFFE, and CoF were significantly correlated with each othe, with SF-36, and with mobility. The ABC and mSAFFE were significantly correlated with PASE. The ABC differentiated between fallers and nonfallers and predicted total falls risk. Findings can assist with the selection of psychological instruments in a falls risk screening context.

Calcium promotes exopolysaccharide phase variation and biofilm formation of the resulting phase variants in the human pathogen Vibrio vulnificus.

Vibrio vulnificus is a Gram-negative bacterium found in estuaries and coastal waters and is associated with human disease caused by ingestion of raw shellfish. Pathogenesis is directly related to the presence of capsular polysaccharide (CPS). Encapsulated virulent strains exhibit an opaque colony phenotype, while unencapsulated attenuated strains appear translucent. A third colony type, rugose, is caused by expression of rugose extracellular polysaccharide (rEPS) and forms robust biofilms. Vibrio vulnificus undergoes phase variation associated with altered levels of CPS and rEPS, and we show here that calcium (Ca²(+) ) significantly increases the rate of CPS and rEPS phase variation in this species. Interestingly, multiple phenotypic responses to increased [Ca²(+) ] were observed among strains, which suggests the existence of underlying cognate genetic or epigenetic differences. Certain translucent isolates contained deletions at the group I CPS operon, inferring increased [Ca²(+) ] upregulates existing phase variation mechanisms. Expanding on a previous observation (Kierek and Watnick, Proc. Natl. Acad. Sci. USA 100: 14357-14362, 2003), increased [Ca²(+) ] also enhanced biofilm formation for all phase variants. Our results show that Ca²(+) promotes both polysaccharide phase variation and biofilm formation of the resulting phase variants, thereby likely serving a dual role in persistence of V. vulnificus in the environment.

Geographic, seasonal, and precipitation chemistry influence on the abundance and activity of biological ice nucleators in rain and snow.

Biological ice nucleators (IN) function as catalysts for freezing at relatively warm temperatures (warmer than -10 degrees C). We examined the concentration (per volume of liquid) and nature of IN in precipitation collected from Montana and Louisiana, the Alps and Pyrenees (France), Ross Island (Antarctica), and Yukon (Canada). The temperature of detectable ice-nucleating activity for more than half of the samples was > or = -5 degrees C based on immersion freezing testing. Digestion of the samples with lysozyme (i.e., to hydrolyze bacterial cell walls) led to reductions in the frequency of freezing (0-100%); heat treatment greatly reduced (95% average) or completely eliminated ice nucleation at the measured conditions in every sample. These behaviors were consistent with the activity being bacterial and/or proteinaceous in origin. Statistical analysis revealed seasonal similarities between warm-temperature ice-nucleating activities in snow samples collected over 7 months in Montana. Multiple regression was used to construct models with biogeochemical data [major ions, total organic carbon (TOC), particle, and cell concentration] that were accurate in predicting the concentration of microbial cells and biological IN in precipitation based on the concentration of TOC, Ca(2+), and NH(4)(+), or TOC, cells, Ca(2+), NH(4)(+), K(+), PO(4)(3-), SO(4)(2-), Cl(-), and HCO(3)(-). Our results indicate that biological IN are ubiquitous in precipitation and that for some geographic locations the activity and concentration of these particles is related to the season and precipitation chemistry. Thus, our research suggests that biological IN are widespread in the atmosphere and may affect meteorological processes that lead to precipitation.

Reading nutrition labels and fat consumption in adolescents.

We studied the relationship between reading nutrition labels and percent calorie intake from fat. In adolescent boys, reading nutrition labels was associated with higher fat intake. In girls, fat intake did not differ by frequency of nutrition label reading. Nutrition label reading does not translate into healthier diet in adolescents.

Use of a brief Smoking Consequences Questionnaire for Adults (SCQ-A) in African American smokers.

Purposes of the present study were to (a) examine psychometric properties of a brief Smoking Consequences Questionnaire-Adult (SCQ-A) among an African American sample and (b) explore differences in smoking expectancies across levels of smoking-nicotine dependence. Four hundred eighty-four smokers attending an urban health clinic completed the brief SCQ-A. Maximum likelihood factor extraction with a varimax rotation specifying 9 factors replicated 9 factors of the original SCQ-A. Evidence for the brief SCQ-A's reliability and validity was found. Heavier and/or more dependent smokers had significantly higher scores than lighter and/or less dependent smokers on positive expectancies SCQ-A subscales. Results suggest the brief SCQ-A may be a useful alternative to the full scale SCQ-A. Results also provide evidence for the SCQ-A's validity with African American smokers.

Predicting adoption of home smoking restriction by inner-city black smokers.

OBJECTIVE: To identify predictors of future adoption of home smoking restriction (HSR), given that 40% of inner-city smokers report current HSR. DESIGN: Secondary analysis of data on smokers enrolled in a double-blind, placebo-controlled, randomized trial of bupropion hydrochloride for smoking cessation. SETTING: Community health center in Kansas City, Kan, from August 1, 2000, to December 31, 2001. PARTICIPANTS: Six hundred eligible black smokers, at least 18 years old, who smoked at least 10 cigarettes per day and were interested in quitting within the next 30 days. Enrollment was limited to 1 smoker per household. MAIN OUTCOME MEASURES: Adoption of HSR by 6 months by those who did not have it at baseline. Result Baseline HSR was reported by 36% of all smokers. Of 383 smokers without baseline HSR, 311 smokers had complete baseline and 6-month data. Thirty-seven percent of households without HSR at baseline had adopted HSR by 6 months. Adoption was associated with a nonsmoking adult or children in the home, progress in stage of change, and smoking cessation. Odds of adopting HSR increased with progress in stage of change (odds ratio [OR], 4.20), baseline preparatory stage of change (OR, 3.28), and having a nonsmoking partner (OR, 2.35) or children (OR, 1.75) in the home. CONCLUSIONS: A smoker's motivation to quit and the presence in the home of a nonsmoking adult or of children predict adoption of HSR by inner-city black smokers. Therefore, health professionals should motivate the smoker toward HSR and the nonsmoking partner toward advocating home smoking bans, thereby eliminating environmental tobacco smoke in the home.