605 research outputs found

    Robust singleā€walled carbon nanotubeā€infiltrated carbon fiber electrodes for structural supercapacitors: from reductive dissolution to high performance devices

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    Multifunctional electrodes for structural supercapacitors are prepared by vacuum infiltration of single-walled carbon nanotubes (SWCNTs) into woven carbon fibers (CFs); the use of reductive charging chemistry to form nanotubide solutions ensured a high degree of individualization. The route is highly versatile, as shown by comparing four different commercial nanotube feedstocks. In film form, the pure nanotubide networks (ā€œbuckypapersā€) are highly conductive (up to 2000 S cmāˆ’1) with high surface area (>1000 m2 gāˆ’1) and great electrochemical performance (capacitance of 101 F gāˆ’1, energy density of 27.5 Wh kgāˆ’1 and power density of 135 kW kgāˆ’1). Uniformly integrating these SWCNT networks throughout the CF fabrics significantly increased electrical conductivity (up to 318 S cmāˆ’1), surface area (up to 196 m2 gāˆ’1), and in-plane shear properties, all simultaneously. The CNT-infiltrated CFs electrodes exhibited intrinsically high specific energy (2.6ā€“4.2 Wh kgāˆ’1) and power (6.0ā€“8.7 kW kgāˆ’1) densities in pure 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM TFSI) electrolyte. Multifunctional structural supercapacitors based on CNT-coated CFs offer a substantial increase in capacitive performance while maintaining the tensile mechanical properties of the as-received CF-based composite. This non-damaging approach to modify CFs with highly graphitic, high surface area nanocarbons provides a new route to structural energy storage systems

    Species-specific differences in the Pro-Ala rich region of cardiac myosin binding protein-C

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    Cardiac myosin binding protein-C (cMyBP-C) is an accessory protein found in the A-bands of vertebrate sarcomeres and mutations in the cMyBP-C gene are a leading cause of familial hypertrophic cardiomyopathy. The regulatory functions of cMyBP-C have been attributed to the N-terminus of the protein, which is composed of tandem immunoglobulin (Ig)-like domains (C0, C1, and C2), a region rich in proline and alanine residues (the Pro-Ala rich region) that links C0 and C1, and a unique sequence referred to as the MyBP-C motif, or M-domain, that links C1 and C2. Recombinant proteins that contain various combinations of the N-terminal domains of cMyBP-C can activate actomyosin interactions in the absence of Ca2+, but the specific sequences required for these effects differ between species; the Pro-Ala region has been implicated in human cMyBP-C whereas the C1 and M-domains appear important in mouse cMyBP-C. To investigate whether species-specific differences in sequence can account for the observed differences in function, we compared sequences of the Pro-Ala rich region in cMyBP-C isoforms from different species. Here we report that the number of proline and alanine residues in the Pro-Ala rich region varies significantly between different species and that the number correlates directly with mammalian body size and inversely with heart rate. Thus, systematic sequence differences in the Pro-Ala rich region of cMyBP-C may contribute to observed functional differences in human versus mouse cMyBP-C isoforms and suggest that the Pro-Ala region may be important in matching contractile speed to cardiac function across species

    Subtle changes in the flavour and texture of a drink enhance expectations of satiety

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    Background: The consumption of liquid calories has been implicated in the development of obesity and weight gain. Energy-containing drinks are often reported to have a weak satiety value: one explanation for this is that because of their fluid texture they are not expected to have much nutritional value. It is important to consider what features of these drinks can be manipulated to enhance their expected satiety value. Two studies investigated the perception of subtle changes in a drinkā€™s viscosity, and the extent to which thick texture and creamy flavour contribute to the generation of satiety expectations. Participants in the first study rated the sensory characteristics of 16 fruit yogurt drinks of increasing viscosity. In study two, a new set of participants evaluated eight versions of the fruit yogurt drink, which varied in thick texture, creamy flavour and energy content, for sensory and hedonic characteristics and satiety expectations. Results: In study one, participants were able to perceive small changes in drink viscosity that were strongly related to the actual viscosity of the drinks. In study two, the thick versions of the drink were expected to be more filling and have a greater expected satiety value, independent of the drinkā€™s actual energy content. A creamy flavour enhanced the extent to which the drink was expected to be filling, but did not affect its expected satiety. Conclusions: These results indicate that subtle manipulations of texture and creamy flavour can increase expectations that a fruit yogurt drink will be filling and suppress hunger, irrespective of the drinkā€™s energy content. A thicker texture enhanced expectations of satiety to a greater extent than a creamier flavour, and may be one way to improve the anticipated satiating value of energy-containing beverages

    Is there a protective effect of normal to high intellectual function on mental health in children with chronic illness?

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    <p>Abstract</p> <p>Background</p> <p>High intellectual function is considered as a protective factor for children's mental health. Few studies have investigated the effect of intellectual function on mental health in children with chronic illness (CI). The aim of the present study was twofold: First, we asked if <it>normal to high </it>intellectual function (IQ) has a protective effect on mental health in children with CI, and secondly, if this effect is more substantial than in their peers (NCI).</p> <p>Methods</p> <p>The participants were selected among children who participated in the Bergen Child Study (BCS): 96 children with CI (the CI-group) and 96 children without CI (the NCI-group). The groups were matched on intellectual function as measured by the WISC-III by selecting the same number of children from three levels of the Full Scale IQ Score (FSIQ): "very low" (<70),"low" (70 to 84), or "normal to high" (>84). CI was reported by parents as part of a diagnostic interview (Kiddie-SADS-PL) that also generated the mental health measures used in the present study: the presence of a DSM-IV psychiatric diagnosis and the score on the Children's Global Assessment Scale.</p> <p>Results</p> <p>The risk of a psychiatric diagnosis was significantly lower for children with a normal to high FSIQ-level than for children with a very low and low FSIQ-level in the CI-group as well as in the NCI-group. The group differences were statistically non-significant for all three FSIQ-levels, and the effect of the interaction between the group-variable (CI/NCI) and the FSIQ-level was non-significant on both measures of mental health.</p> <p>Conclusion</p> <p>The present study showed a protective effect of normal to high intellectual function on children's mental health. This protective effect was not more substantial in children with CI than in children without CI.</p

    Personality, personnel selection, and job performance

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    Job Performance: The term job performance can either refer to the objective or subjective outcomes one achieves in a specific job (e.g., the profit of a sales persons, the number of publications of a scientist, the number of successful operations of a surgeon) or to work-related activities (e.g., writing an article, conducting specific surgical acts). In the majority of research on this topic, job performance as an outcome is used. Personnel selection: Personnel selection refers to the process of selecting the best employees for specific jobs. Introduction One major application of personality research is in the area of personnel selection. The key question in this area is to which extent personality can predict how well a candidate will perform on the job he or she is applying for. Most scholars in this area acknowledge that personality has predictive validity for job performance. In line with this, personality assessment is part of the selection procedure in many organizations

    Heritable patterns of tooth decay in the permanent dentition: principal components and factor analyses

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    <p>Abstract</p> <p>Background</p> <p>Dental caries is the result of a complex interplay among environmental, behavioral, and genetic factors, with distinct patterns of decay likely due to specific etiologies. Therefore, global measures of decay, such as the DMFS index, may not be optimal for identifying risk factors that manifest as specific decay patterns, especially if the risk factors such as genetic susceptibility loci have small individual effects. We used two methods to extract patterns of decay from surface-level caries data in order to generate novel phenotypes with which to explore the genetic regulation of caries.</p> <p>Methods</p> <p>The 128 tooth surfaces of the permanent dentition were scored as carious or not by intra-oral examination for 1,068 participants aged 18 to 75 years from 664 biological families. Principal components analysis (PCA) and factor analysis (FA), two methods of identifying underlying patterns without <it>a priori </it>surface classifications, were applied to our data.</p> <p>Results</p> <p>The three strongest caries patterns identified by PCA recaptured variation represented by DMFS index (correlation, r = 0.97), pit and fissure surface caries (r = 0.95), and smooth surface caries (r = 0.89). However, together, these three patterns explained only 37% of the variability in the data, indicating that <it>a priori </it>caries measures are insufficient for fully quantifying caries variation. In comparison, the first pattern identified by FA was strongly correlated with pit and fissure surface caries (r = 0.81), but other identified patterns, including a second pattern representing caries of the maxillary incisors, were not representative of any previously defined caries indices. Some patterns identified by PCA and FA were heritable (h<sup>2 </sup>= 30-65%, p = 0.043-0.006), whereas other patterns were not, indicating both genetic and non-genetic etiologies of individual decay patterns.</p> <p>Conclusions</p> <p>This study demonstrates the use of decay patterns as novel phenotypes to assist in understanding the multifactorial nature of dental caries.</p

    Life experiences throughout the ifespan: What do people say (or not) about them?

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    Life experiences have been a topic of interest for researchers and clinicians for decades. Current knowledge is rooted in two distinct approaches, i.e., personality psychology and psychosomatics. Whereas the first is interested in ordinary life stories of nonclinical individuals, based on a more qualitative, in-depth, and person-driven approach, psychosomatics stresses negative events, mainly in clinical samples, and presents a more quantitative, general, and construct-driven approach. Consequently, available evidence is dispersed and unrelated and many basic questions remain unanswered. This study aimed to explore occurrence, developmental stage, valence, and impact of life experiences and to analyze critical answering patterns (i.e., ā€œI donā€™t remember,ā€ missingness). Through a cross-sectional retrospective design, 394 adults from the community answered the Lifetime Experiences Scale, which covers 75 life experiences organized in eight domains (i.e., school, job, health, leisure, living conditions, adverse experiences, achievements, and people and relationships). Occurrence of life experiences varied greatly, and the mean number of experiences reported was approximately 30. Regarding developmental stage, most experiences were reported in just one stageā€”mainly adulthoodā€”however, some could be considered chronic. Globally, life experiences tended to be clearly rated as positive or as negative; additionally, assessed experiences were mainly appraised as positive. Moreover, participants presented their experiences as significant, rating them as high impact. Overall, critical answering patterns were not very expressive: ā€œI donā€™t rememberā€ and missing answers were below 2 and 5%, respectively, in the majority of experiences. These findings offer several important new insights, suggesting that life experiences are mainly an idiosyncratic topic.This manuscript is part of a doctoral dissertation, which had the support of the Portuguese Foundation for Science and Technology (FCT), through the PhD grant with the reference SFRH/ BD/76022/2011, funded by POPH-QREN-Typology 4.1-Advanced Training, reimbursed by the European Social Fund and national funds from State Budget. This study was conducted at Psychology Research Centre (UID/PSI/01662/2013), University of Minho, and supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Education and Science through national funds and co-financed by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653).info:eu-repo/semantics/publishedVersio

    Genetic and environmental influences on the relation between attention problems and Attention Deficit Hyperactivity Disorder.

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    Objective: The assessment of symptoms of ADHD in children is usually based on a clinical interview or a behavior checklist. The aim of the present study is to investigate the extent to which these instruments measure an underlying construct and to estimate the genetic and environmental influences on individual differences in ADHD. Methods: Maternal ratings were collected on 10,916 twins from 5,458 families. Child Behavior Checklist (CBCL) ratings were available for 10,018, 6,565, and 5,780 twins at the ages 7, 10, and 12, respectively. The Conners Rating Scale (4,887 twins) and the DSM interview (1,006 twins) were completed at age 12. The magnitude of genetic and environmental influences on the variance of the three measures of ADHD and the covariance among the three measures of ADHD was obtained. Results: Phenotypic correlations range between .45 and .77. Variances and covariances of the measurements were explained mainly by genetic influences. The model that provided the best account of the data included an independent pathway for additive and dominant genetic effects. The genetic correlations among the measures collected at age 12 varied between .63 and 1.00. Conclusions: The genetic overlap between questionnaire ratings and the DSM-IV diagnosis of ADHD is high. Clinical and research implications of these findings are presented

    High Uptake of Exclusive Breastfeeding and Reduced Early Post-Natal HIV Transmission

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    BACKGROUND. Empirical data showing the clear benefits of exclusive breastfeeding (EBF) for HIV prevention are needed to encourage implementation of lactation support programs for HIV-infected women in low resource settings among whom replacement feeding is unsafe. We conducted a prospective, observational study in Lusaka, Zambia, to test the hypothesis that EBF is associated with a lower risk of postnatal HIV transmission than non-EBF. METHODS AND RESULTS. As part of a randomized trial of early weaning, 958 HIV-infected women and their infants were recruited and all were encouraged to breastfeed exclusively to 4 months. Single-dose nevirapine was provided to prevent transmission. Regular samples were collected from infants to 24 months of age and tested by PCR. Detailed measurements of actual feeding behaviors were collected to examine, in an observational analysis, associations between feeding practices and postnatal HIV transmission. Uptake of EBF was high with 84% of women reporting only EBF cumulatively to 4 months. Post-natal HIV transmission before 4 months was significantly lower (pā€Š=ā€Š0.004) among EBF (0.040 95% CI: 0.024ā€“0.055) than non-EBF infants (0.102 95% CI: 0.047ā€“0.157); time-dependent Relative Hazard (RH) of transmission due to non-EBFā€Š=ā€Š3.48 (95% CI: 1.71ā€“7.08). There were no significant differences in the severity of disease between EBF and non-EBF mothers and the association remained significant (RHā€Š=ā€Š2.68 95% CI: 1.28ā€“5.62) after adjusting for maternal CD4 count, plasma viral load, syphilis screening results and low birth weight. CONCLUSIONS. Non-EBF more than doubles the risk of early postnatal HIV transmission. Programs to support EBF should be expanded universally in low resource settings. EBF is an affordable, feasible, acceptable, safe and sustainable practice that also reduces HIV transmission providing HIV-infected women with a means to protect their children's lives. TRIAL REGISTRATION. ClinicalTrials.gov NCT00310726National Institute of Child Health and Human Development; National Institutes of Health (R01 HD 39611, R01 HD 40777); Centers for Disease Control and Prevention; Global AIDS Program; Glaser Pediatric AIDS Foundation; USAID Country Research (GHS-A-00-00020-00
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