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Phosphorescent organic light emitting diodes (OLEDs) suffer from efficiency roll off, where device efficiency rapidly decays at higher luminance. One strategy to minimize this loss of efficiency at higher luminance is the use of non-uniform or graded guest:host blend ratios within the emissive layer. This work applies a multi-scale modeling framework to elucidate the mechanisms by which a non-uniform blend ratio can change the performance of an OLED. Mobility and exciton data are extracted from a kinetic Monte–Carlo model, which is then coupled to a drift diffusion model for fast sampling of the parameter space. The model is applied to OLEDs with uniform, linear, and stepwise graduations in the blend ratio in the emissive layer. The distribution of the guests in the film was found to affect the mobility of the charge carriers, and it was determined that having a graduated guest profile broadened the recombination zone, leading to a reduction in second order annihilation rates. That is, there was a reduction in triplet–triplet and triplet-polaron annihilation. Reducing triplet–triplet and triplet-polaron annihilation would lead to an improvement in device efficiency. [ABSTRACT FROM AUTHOR]

Key unresolved questions about particle separation mechanisms in suspensionfeeding fishes are identified and discussed, focusing on areas with the potential for substantial future discovery. The published hypotheses that are explored have broad applicability to biological filtration and bioinspired improvements in commercial and industrial crossflow microfiltration processes and microfluidics. As the first synthesis of the primary literature on the particle separation mechanisms of marine, estuarine, and freshwater suspension-feeding fishes, the goals are to enable comparisons with invertebrate suspension-feeding processes, stimulate future theoretical and empirical studies, and further the development of biomimetic physical and computational fluid dynamics models. Of the eight particle separation mechanisms in suspension-feeding fishes, six have been proposed within the past twenty years (inertial lift and shear-induced migration, reduction of effective gap size by vortices, cross-step filtration, vortical flow along outer faces of gill raker plates, ricochet filtration, and lateral displacement). The pace of discovery is anticipated to continue accelerating. Multidisciplinary collaboration and integration among biologists and engineers (including chemical, mechanical, biomedical, and filtration engineering) will result in new perspectives to identify patterns and potential unifying mechanisms across the breadth of suspension-feeding fish taxa, morphology, and function. [ABSTRACT FROM AUTHOR]

Identifying the immunogenic proteins that elicit pathogen-specific T cell responses is key to rational vaccine design. While several approaches have succeeded in identifying major histocompatibility complex (MHC) class I bound peptides that stimulate CD8+ T cells, these approaches have been difficult to extend to peptides presented by MHC class II molecules that stimulate CD4+ T cells. We describe here a novel strategy for identifying CD4+ T cell-stimulating antigen genes. Using Listeria monocytogenes-specific, lacZ-inducible T cells as single-cell probes, we screened a Listeria monocytogenes genomic library as recombinant Escherichia coli that were fed to macrophages. The antigen gene was isolated from the E. coli clone that, when ingested by the macrophages, allowed generation of the appropriate peptide/MHC class II complex and T cell activation. We show that the antigenic peptide is derived from a previously unknown listeria gene product with characteristics of a membrane-bound protein.

We show that goldfish (Carassius auratus) voluntarily ingest liquid canola oil at the surface of the water and can swallow significant quantities of oil. The ability of fish to separate floating oil from water has not been tested previously, and the mechanisms used to retain oil in the form of suspended droplets, globules, or a surface film are unknown. Chromatograms of fatty acid methyl esters (FAMEs) prepared from gut samples confirmed that goldfish were able to obtain a substantial proportion of their daily lipid intake from canola oil at the surface of laboratory aquaria. Quantification of goldfish suspension-feeding, processing, and spitting behavior suggested that upper jaw protrusion with a closed mouth during processing was important for the handling of different food types, including oil. Crossflow filtration and the generation of vortices could be involved in oil retention by goldfish, as these processes are used industrially to separate oil from water. These results have implications for the uptake of hydrophobic pollutants and dietary lipids at the surface by suspension-feeding fishes. Nous demontrons que le carassin dore (Carassius auratus) ingere volontairement de l'huile de canola liquide a la surface de l'eau et peut avaler d'importantes quantites d'huile. La capacite des poissons de separer de l'eau l'huile qui flotte n'a pas encore ete verifiee, et les mecanismes utilises pour retenir l'huile sous forme de gouttelettes suspendues, de globules ou de film superficiel ne sont pas connus. Des chromatogrammes d'esters methyliques d'acide gras (EMAG) prepares a partir d'echantillons de tubes digestifs confirment que les carassins dores sont capables d'obtenir une proportion importante de leur apport quotidien en lipides de l'huile de canola a la surface d'aquariums de laboratoire. La quantification du comportement de consommation de matieres en suspension, de traitement et de rejet par les carassins dores donne a penser que la protrusion de la machoire superieure pendant que la bouche est fermee durant le traitement est importante pour traiter differents types d'aliments, dont l'huile. La filtration perpendiculaire a l'ecoulement et la production de vortex pourraient intervenir dans la retention d'huile par les carassins dores, ces processus etant utilises dans l'industrie pour separer l'huile de l'eau. Ces resultats ont des repercussions en ce qui concerne l'ingestion de contaminants hydrophobes et de lipides alimentaires a la surface de l'eau par les poissons qui se nourrissent de matieres en suspension. [Traduit par la Redaction], Introduction Suspension-feeding fishes with economic and ecological importance, including carp, menhaden, and many tilapia, can filter particles as small as 5 microns from enormous volumes of water (Beveridge et al. [...]

Objective: To evaluate the association of Jewish cultural and religious identity and denominational affiliation with interest in, intention to undertake and uptake of population‐based BRCA (Breast Cancer Gene)‐testing. Design: Cohort‐study set within recruitment to GCaPPS‐trial (ISRCTN73338115). Setting: London Ashkenazi‐Jewish (AJ) population. Population or sample: AJ men and women, >18 years. Methods: Participants were self‐referred, and attended recruitment clinics (clusters) for pre‐test counselling. Subsequently consenting individuals underwent BRCA testing. Participants self‐identified to one Jewish denomination: Conservative/Liberal/Reform/Traditional/Orthodox/Unaffiliated. Validated scales measured Jewish Cultural‐Identity (JI) and Jewish Religious‐identity (JR). Four‐item Likert‐scales analysed initial 'interest' and 'intention to test' pre‐counselling. Item‐Response‐Theory and graded‐response models, modelled responses to JI and JR scales. Ordered/multinomial logistic regression modelling evaluated association of JI‐scale, JR‐scale and Jewish Denominational affiliation on interest, intention and uptake of BRCA testing. Main outcome measures: Interest, intention, uptake of BRCA testing. Results: In all, 935 AJ women/men of mean age = 53.8 (S.D = 15.02) years, received pre‐test education and counselling through 256 recruitment clinic clusters (median cluster size = 3). Denominational affiliations included Conservative/Masorti = 91 (10.2%); Liberal = 82 (9.2%), Reform = 135 (15.1%), Traditional = 212 (23.7%), Orthodox = 239 (26.7%); and Unaffiliated/Non‐practising = 135 (15.1%). Overall BRCA testing uptake was 88%. Pre‐counselling, 96% expressed interest and 60% intention to test. JI and JR scores were highest for Orthodox, followed by Conservative/Masorti, Traditional, Reform, Liberal and Unaffiliated Jewish denominations. Regression modelling showed no significant association between overall Jewish Cultural or Religious Identity with either interest, intention or uptake of BRCA testing. Interest, intention and uptake of BRCA testing was not significantly associated with denominational affiliation. Conclusions: Jewish religious/cultural identity and denominational affiliation do not appear to influence interest, intention or uptake of population‐based BRCA testing. BRCA testing was robust across all Jewish denominations. Jewish cultural/religious factors do not affect BRCA testing, with robust uptake seen across all denominational affiliations. Jewish cultural/religious factors do not affect BRCA testing, with robust uptake seen across all denominational affiliations. [ABSTRACT FROM AUTHOR]

To assess potential filtration mechanisms, scanning electron microscopy was used in a comprehensive quantification and analysis of the morphology and surface ultrastructure for all five branchial arches in the ram suspension‐feeding fish, American shad (Alosa sapidissima, Clupeidae). The orientation of the branchial arches and the location of mucus cells on the gill rakers were more consistent with mechanisms of crossflow filtration and cross‐step filtration rather than conventional dead‐end sieving. The long, thin gill rakers could lead to a large area for the exit of water from the oropharyngeal cavity during suspension feeding (high fluid exit ratio). The substantial elongation of gill rakers along the dorsal‐ventral axis formed d‐type ribs with a groove aspect ratio of 0.5 and a Reynolds number of approximately 500, consistent with the potential operation of cross‐step filtration. Mucus cell abundance differed significantly along the length of the raker and the height of the raker. The mucus cell abundance data and the observed sloughing of denticles along the gill raker margins closest to the interior of the oropharyngeal cavity suggest that gill raker growth may occur primarily at the raker tips, the denticle bases, and the internal raker margins along the length of the raker. These findings will be applied in ongoing experiments with 3D‐printed physical models of fish oral cavities in flow tanks, and in future ecological studies on the diet and nutrition of suspension‐feeding fishes. Research Highlights: The morphology of American shad mouths is consistent with models of crossflow and cross‐step filtration rather than dead‐end sieving. The rib‐and‐groove arrangements of gill rakers in herrings and sardines may function as filtration engineering structures. [ABSTRACT FROM AUTHOR]

Objective: Unselected population-based BRCA testing provides the opportunity to apply genomics on a population-scale to maximise primary prevention for breast-and-ovarian cancer. We compare long-term outcomes of population-based and family-history (FH)/clinical-criteria-based BRCA testing on psychological health and quality of life.Design: Randomised controlled trial (RCT) (ISRCTN73338115) GCaPPS, with two-arms: (i) population-screening (PS); (ii) FH/clinical-criteria-based testing.Setting: North London Ashkenazi-Jewish (AJ) population.Population/sample: AJ women/men.Methods: Population-based RCT (1:1). Participants were recruited through self-referral, following pre-test genetic counselling from the North London AJ population.Inclusion Criteria: AJ women/men >18 years old; exclusion-criteria: prior BRCA testing or first-degree relatives of BRCA-carriers.Interventions: Genetic testing for three Jewish BRCA founder-mutations: 185delAG (c.68_69delAG), 5382insC (c.5266dupC) and 6174delT (c.5946delT), for (i) all participants in PS arm; (ii) those fulfilling FH/clinical criteria in FH arm. Linear mixed models and appropriate contrast tests were used to analyse the impact of BRCA testing on psychological and quality-of-life outcomes over 3 years.Main Outcome Measures: Validated questionnaires (HADS/MICRA/HAI/SF12) used to analyse psychological wellbeing/quality-of-life outcomes at baseline/1-year/2-year/3-year follow up.Results: In all, 1034 individuals (691 women, 343 men) were randomised to PS (n = 530) or FH (n = 504) arms. There was a statistically significant decrease in anxiety (P = 0.046) and total anxiety-&-depression scores (P = 0.0.012) in the PS arm compared with the FH arm over 3 years. No significant difference was observed between the FH and PS arms for depression, health-anxiety, distress, uncertainty, quality-of-life or experience scores associated with BRCA testing. Contrast tests showed a decrease in anxiety (P = 0.018), health-anxiety (P < 0.0005) and quality-of-life (P = 0.004) scores in both PS and FH groups over time. Eighteen of 30 (60%) BRCA carriers identified did not fulfil clinical criteria for BRCA testing. Total BRCA prevalence was 2.9% (95% CI 1.97-4.12%), BRCA1 prevalence was 1.55% (95% CI 0.89-2.5%) and BRCA2 prevalence was 1.35% (95% CI 0.74-2.26%).Conclusion: Population-based AJ BRCA testing does not adversely affect long-term psychological wellbeing or quality-of-life, decreases anxiety and could identify up to 150% additional BRCA carriers.Tweetable Abstract: Population BRCA testing in Ashkenazi Jews reduces anxiety and does not adversely affect psychological health or quality of life. [ABSTRACT FROM AUTHOR]

Objective: To evaluate factors affecting unselected population-based BRCA testing in Ashkenazi Jews (AJ).Design: Cohort-study set within recruitment to the GCaPPS trial (ISRCTN73338115).Setting: North London AJ population.Population or Sample: Ashkenazi Jews women/men >18 years, recruited through self-referral.Methods: Ashkenazi Jews women/men underwent pre-test counselling for BRCA testing through recruitment clinics (clusters). Consenting individuals provided blood samples for BRCA testing. Data were collected on socio-demographic/family history/knowledge/psychological well-being along with benefits/risks/cultural influences (18-item questionnaire measuring 'attitude'). Four-item Likert-scales analysed initial 'interest' and 'intention-to-test' pre-counselling. Uni- and multivariable logistic regression models evaluated factors affecting uptake/interest/intention to undergo BRCA testing. Statistical inference was based on cluster robust standard errors and joint Wald tests for significance. Item-Response Theory and graded-response models modelled responses to 18-item questionnaire.Main Outcome Measures: Interest, intention, uptake, attitude towards BRCA testing.Results: A total of 935 individuals (women = 67%/men = 33%; mean age = 53.8 (SD = 15.02) years) underwent pre-test genetic-counselling. During the pre-counselling, 96% expressed interest in and 60% indicated a clear intention to undergo BRCA testing. Subsequently, 88% opted for BRCA testing. BRCA-related knowledge (P = 0.013) and degree-level education (P = 0.01) were positively and negatively (respectively) associated with intention-to-test. Being married/cohabiting had four-fold higher odds for BRCA testing uptake (P = 0.009). Perceived benefits were associated with higher pre-counselling odds for interest in and intention to undergo BRCA testing. Reduced uncertainty/reassurance were the most important factors contributing to decision-making. Increased importance/concern towards risks/limitations (confidentiality/insurance/emotional impact/inability to prevent cancer/marriage ability/ethnic focus/stigmatisation) were significantly associated with lower odds of uptake of BRCA testing, and discriminated between acceptors and decliners. Male gender/degree-level education (P = 0.001) had weaker correlations, whereas having children showed stronger (P = 0.005) associations with attitudes towards BRCA testing.Conclusions: BRCA testing in the AJ population has high acceptability. Pre-test counselling increases awareness of disadvantages/limitations of BRCA testing, influencing final cost-benefit perception and decision-making on undergoing testing.Tweetable Abstract: BRCA testing in Ashkenazi Jews has high acceptability and uptake. Pre-test counselling facilitates informed decision-making. [ABSTRACT FROM AUTHOR]

Vortical cross-step filtration in suspension-feeding fish has been reported recently as a novel mechanism, distinct from other biological and industrial filtration processes. Although crossflow passing over backward-facing steps generates vortices that can suspend, concentrate, and transport particles, the morphological factors affecting this vortical flow have not been identified previously. In our 3D-printed models of the oral cavity for ram suspension-feeding fish, the angle of the backward-facing step with respect to the model’s dorsal midline affected vortex parameters significantly, including rotational, tangential, and axial speed. These vortices were comparable to those quantified downstream of the backward-facing steps that were formed by the branchial arches of preserved American paddlefish in a recirculating flow tank. Our data indicate that vortices in cross-step filtration have the characteristics of forced vortices, as the flow of water inside the oral cavity provides the external torque required to sustain forced vortices. Additionally, we quantified a new variable for ram suspension feeding termed the fluid exit ratio. This is defined as the ratio of the total open pore area for water leaving the oral cavity via spaces between branchial arches that are not blocked by gill rakers, divided by the total area for water entering through the gape during ram suspension feeding. Our experiments demonstrated that the fluid exit ratio in preserved paddlefish was a significant predictor of the flow speeds that were quantified anterior of the rostrum, at the gape, directly dorsal of the first ceratobranchial, and in the forced vortex generated by the first ceratobranchial. Physical modeling of vortical cross-step filtration offers future opportunities to explore the complex interactions between structural features of the oral cavity, vortex parameters, motile particle behavior, and particle morphology that determine the suspension, concentration, and transport of particles within the oral cavity of ram suspension-feeding fish. [ABSTRACT FROM AUTHOR]

Ram suspension-feeding fishes swim with an open mouth to force water through the oral cavity and extract prey items that are too small to be pursued individually. Recent research has indicated that, rather than using a dead-end mechanical sieve, American paddlefish (Polyodon spathula) employ vortical cross-step filtration. In this filtration mechanism, vortical flow that is generated posterior to the branchial arches organizes crossflow filtration processes into a spatial structure across the gill rakers. Despite the known impact of locomotor kinematics on fluid flow around the bodies of swimming fish, the effects of locomotor kinematics on filtration mechanisms in ram suspension feeders are unknown. Potential temporal organization of filtration mechanisms in ram suspension-feeding fish has not been studied previously. We investigated the effects of locomotor kinematics associated with undulatory swimming on intraoral flow patterns and food particle transport. A mechanized model of the oral cavity was used to simulate the swimming kinematics of suspension-feeding paddlefish. We recorded fluctuations of flow speed and pressure within the model, which occurred at a frequency that corresponded with the frequency of the model's strides. Using the mechanized model in a flow tank seeded with Artemia cysts, we also showed that swimming kinematics aided the transport of this simulated food to the posterior margins of the gill slots, although the time scale of this transport is expected to vary with prey parameters such as size and concentration. Dye stream experiments revealed that, although stable vortical flow formed because of flow separation downstream of backward-facing steps in control trials, vortical flow structures in mechanized trials repeatedly formed and shed. These findings suggest strong integration between locomotor and feeding systems in ram suspension-feeding fishes. [ABSTRACT FROM AUTHOR]