421 research outputs found

    Assessing tracheal health using optical metabolic imaging and optical coherence tomography

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    The health and pathophysiology of the tracheal mucosa is an important yet poorly understood aspect of respiratory medicine. Cilia, hair-like organelles important for mucociliary clearance, line the tracheal mucosa. Ciliary dysfunction leads to severe diseases such as primary ciliary dyskinesia and cystic fibrosis. Optical imaging can monitor ciliary function in vivo, ex vivo, and in vitro to understand the genesis of ciliary disease and potential treatment targets. Specifically, optical coherence tomography (OCT) has been used to quantify multiple parameters of ciliary motility in 2D and 3D. However, OCT inherently lacks information about the biochemical or metabolic state of cells. Optical metabolic imaging (OMI) quantitatively assesses cellular metabolism by imaging the autofluorescence intensities of endogenous metabolic co-enzymes nicotinamide dinucleotide (NADH) and flavin adenine dinucleotide (FAD). OMI probes the optical redox ratio (NADH intensity divided by FAD intensity), which is sensitive to the relative amounts of electron donors and acceptors within a cell. Ciliary function is highly dependent on ATP and therefore tightly linked to NADH and FAD levels through multiple metabolic pathways Please click Additional Files below to see the full abstract

    Bioassay-guided isolation and identification of antimicrobial compounds from thyme essential oil by means of overpressured layer chromatography, bioautography and GC-MS

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    A simple method is described for efficient isolation of compounds having an antibacterial effect. Two thyme (Thymus vulgaris) essential oils, obtained from the market, were chosen as prospective materials likely to feature several bioactive components when examined by thin layer chromatography coupled with direct bioautography as a screening method. The newly developed infusion overpressured layer chromatographic separation method coupled with direct bioautography assured that only the active components were isolated by means of overrun overpressured layer chromatography with online detection and fractionation. Each of the 5 collected fractions represented one of the five antimicrobial essential oil components designated at the screening. The purity and the activity of the fractions were confirmed with chromatography coupled various detection methods (UV, vanillin-sulphuric acid reagent, direct bioautography). The antibacterial components were identified with GC-MS as thymol, carvacrol, linalool, diethylphthalate, and alpha-terpineol. The oil component diethyl-phthalate is an artificial compound, used as plasticizer or detergent bases in the industry. Our results support that exploiting its flexibility and the possible hyphenations, overpressured layer chromatography is especially attractive for isolation of antimicrobial components from various matrixes

    Piecing Together the American Voting Puzzle: How Votersâ Personalities and Judgments of Issue Importance Mattered in the 2016 Presidential Election

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    In the wake of the 2016 election, which surprised pundits and voters on both the left and the right, there has been renewed interest in understanding what predicts American votersâ choices. In this article, we investigate the roles of personality and issue importance in how people voted in the 2016 U.S. election. In this longitudinal study of 403 MTurk workers who voted in the election, we assessed the relations between personality (openness, social dominance orientation, and national identity importance) and issue importance (group rights and social justice, economic rights, and individual and national rights), and voting for Clinton or Trump. Our results indicate that both individual differences and issue importance as measured in July 2016 predicted votes in November. We also found that the links between personality and voting were mediated by issue importance. Implications for political psychology and the study of personality, campaign issues, and voting behavior are discussed.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146841/1/asap12157.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146841/2/asap12157_am.pd

    Detection of antibacterial activity of essential oil components by TLC-bioautography using luminescent bacteria

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    The aim of the present study was the chemical characterization of some medically relevant essential oils (tea tree, clove, cinnamon bark, thyme and eucalyptus) and the investigation of antibacterial effect of the components of these oils by use of a direct bioautographic method. Thin layer chromatography (TLC) was combined with biological detection in this process. The chemical composition of the oils was determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Eucalyptol (84.2%) was the main component of the essential oil of eucalyptus, eugenol (83.7%) of clove oil, and trans-cinnamic aldehyde (73.2%), thymol (49.9%) and terpinen-4-ol (45.8%) of cinnamon bark, thyme and tea tree oils, respectively. Antibacterial activity of the separated components of these oils, as well as their pure main components (eucalyptol, eugenol, trans-cinnamic aldehyde and thymol) was observed against the Gram-negative luminescence tagged plant pathogenic bacterium Pseudomonas syringae pv. maculicola (Psmlux) and the Gram-negative, naturally luminescent marine bacterium Vibrio fischeri. On the whole, the antibacterial activity of the essential oils could be related to their main components, but the minor constituents may be involved in this process. Trans-cinnamic aldehyde and eugenol were the most active compounds in TLC-bioautography. The sensitivity of TLC-bioautographic method can be improved with using luminescent test bacteria. This method is more cost-effective and provides more reliable results in comparison with conventional microbiological methods, e.g. disc-diffusion technique

    Application of direct bioautography and SPME-GC-MS for the study of antibacterial chamomile ingredients

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    The isolation and characterization of antibacterial chamomile components were performed by the use of direct bioautography and solid phase microextraction (SPME)-GC-MS. Four ingredients, active against Vibrio fischeri, were identified as the polyacetylene geometric isomers cis- and trans-spiroethers, the coumarin related herniarin, and the sesquiterpene alcohol (-)-alpha-bisabolol

    Subjects’ perception in quantifying printed and digital photos of food portions

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    Although digital photos have the potential to improve the precision of reported portions in dietary assessment, there are few studies investigating its accuracy in comparison to printed photos. The aim of this study was to evaluate the perception of adults in quantifying food portion sizes using printed and digital photos, displayed on computer-screens and tablets. In total, 1165 evaluations were performed for 60 photos of portion sizes in Brazil. Each participant (n = 58) attended two sessions in the study center, with an interval of at least one week. In each session, twelve food portions were prepared and randomly evaluated by each participant in its printed and digital forms. The mean error (difference between the estimated and true portions) was not significantly different between the printed photos (2.1g ± 47.2) and the digital ones (-6.4g ± 53.7). The agreement on using the printed and digital photos was 91% and 90%, respectively. Furthermore, the use of the tablet was more prone to underestimation when compared to printed and computer-screen photos (p < 0.001). Overall, participants did not present major difficulties in perceiving the portion sizes using the printed and digital photos, but the use of tablets led to less accurate results, indicating that this needs to be further evaluated

    Ultra-high resolution Fourier domain optical coherence tomography for old master paintings

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    In the last 10 years, Optical Coherence Tomography (OCT) has been successfully applied to art conservation, history and archaeology. OCT has the potential to become a routine non-invasive tool in museums allowing cross-section imaging anywhere on an intact object where there are no other methods of obtaining subsurface information. While current commercial OCTs have shown potential in this field, they are still limited in depth resolution (> 4 μm in paint and varnish) compared to conventional microscopic examination of sampled paint cross-sections (~1 μm). An ultrahigh resolution fiber-based Fourier domain optical coherence tomography system with a constant axial resolution of 1.2 μm in varnish or paint throughout a depth range of 1.5 mm has been developed. While Fourier domain OCT of similar resolution has been demonstrated recently, the sensitivity roll-off of some of these systems are still significant. In contrast, this current system achieved a sensitivity roll-off that is less than 2 dB over a 1.2 mm depth range with an incident power of ~1 mW on the sample. The high resolution and sensitivity of the system makes it convenient to image thin varnish and glaze layers with unprecedented contrast. The non-invasive 'virtual' cross-section images obtained with the system show the thin varnish layers with similar resolution in the depth direction but superior clarity in the layer interfaces when compared with conventional optical microscope images of actual paint sample cross-sections obtained microdestructively

    I read it on reddit: Exploring the role of online communities in the 2016 US elections news cycle

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    Reddit has developed into a significant platform for political discussion among Millennials. In this exploratory study, we examine subscription trends on three political sub-forums on Reddit during the 2016 US presidential elections: /The_Donald, /SandersForPresident, and /HillaryClinton. As a theoretical framework, we draw from work on online communities’ group identity and cohesion. Concretely, we investigate how subscription dynamics relate to positive, negative and neutral news events occurring during the election cycle. We classify news events using a sentiment analysis of event-related news headlines. We observe that users who supported Sanders displayed no consolidation of support for Clinton after she won the Democratic Party’s presidential nomination. Secondly, we show that negative news events affected Sanders and Clintons subscription trends negatively, while showing no effect for Donald Trump. This gives empirical credence to Trump’s controversial claim that he could “stand in the middle of 5th Avenue and shoot somebody and not lose any voters”. We offer a number of explanations for the observed phenomena: the nature of the content of the three subreddits, their cultural dynamics, and changing dynamics of partisanship. We posit that the ‘death of expertise’ expresses itself on Reddit as a switch in persuasion tactics from a policy-based to an emotions-based approach, and that group members’ agreement on policy proved a weak marker for online communities’ group identity and cohesion. We also claim that strong partisanship coupled with weak party affiliation among Millennials contributed to the low levels of Democratic support consolidation after Clinton won the nomination

    The person-based nature of prejudice: Individual difference predictors of intergroup negativity

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    Person-based factors influence a range of meaningful life outcomes, including intergroup processes, and have long been implicated in explaining prejudice. In addition to demonstrating significant heritability, person-based factors are evident in expressions of generalised prejudice, a robust finding that some people (relative to others) consistently score higher in prejudice towards multiple outgroups. Our contemporary review includes personality factors, ideological orientations (e.g., authoritarianism), religiosity, anxiety, threat, disgust sensitivity, and cognitive abilities and styles. Meta-analytic syntheses demonstrate that such constructs consistently predict prejudice, often at the upper bounds of effect sizes observed in psychological research. We conclude that prejudice theories need to better integrate person- and situation-based factors, including their interaction, to capture the complexity of prejudice and inform intervention development
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