The self-assembly of particles with isotropic interactions: Using DNA coated colloids to create designer nanomaterials

Copyright (2014) AIP Publishing. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in AIP Conference Proceedings 1590 and may be found at http://dx.doi.org/10.1063/1.4870223Self-consistent field theory equations are presented that are suitable for use as a coarse-grained model for DNA coated colloids, polymer-grafted nanoparticles and other systems with approximately isotropic interactions. The equations are generalized for arbitrary numbers of chemically distinct colloids. The advantages and limitations of such a coarsegrained approach for DNA coated colloids are discussed, as are similarities with block copolymer self-assembly. In particular, preliminary results for three species self-assembly are presented that parallel results from a two dimensional ABC triblock copolymer phase. The possibility of incorporating crystallization, dynamics, inverse statistical mechanics and multiscale modelling techniques are discussed

The major human and mouse granzymes are structurally and functionally divergent

Approximately 2% of mammalian genes encode proteases. Comparative genomics reveals that those involved in immunity and reproduction show the most interspecies diversity and evidence of positive selection during evolution. This is particularly true of granzymes, the cytotoxic proteases of natural killer cells and CD8+ T cells. There are 5 granzyme genes in humans and 10 in mice, and it is suggested that granzymes evolve to meet species-specific immune challenge through gene duplication and more subtle alterations to substrate specificity. We show that mouse and human granzyme B have distinct structural and functional characteristics. Specifically, mouse granzyme B is 30 times less cytotoxic than human granzyme B and does not require Bid for killing but regains cytotoxicity on engineering of its active site cleft. We also show that mouse granzyme A is considerably more cytotoxic than human granzyme A. These results demonstrate that even “orthologous” granzymes have species-specific functions, having evolved in distinct environments that pose different challenges

The influence of source attractiveness on self-perception and advertising effectiveness for 6- to 7-year-old children

The objective of this article is to examine the effects of using attractive peer models in advertising for 6- to 7-year-old children. This age is important in children’s development, as children of that age are not yet fully aware of the persuasive intent of advertising, are more focused on perceptual than on cognitive information in ads and are more focused on irrelevant rather than relevant ad information. More insights are therefore needed about whether attractive advertising models influence self-perception and advertising effectiveness of children this young, in order to help policy makers, parents and advertisers understand these effects. Two experimental studies are presented in which children are exposed to ads with peer models. Results show that when children of 6- to 7-year-old rate advertising models as being more attractive, advertising effectiveness raises, but children’s perceived self-worth and children’s perceived physical attractiveness are unaffected. We conclude that 6- to 7- year-old children use model attractiveness as a perceptual cue to rate ads but are not yet using comparisons with these models to evaluate themselves

‘It's like a bag of pick and mix – you don't know what you are going to get’: young people's experience of neurofibromatosis Type 1

Aims: To explore the day-to-day experience of young people living with neurofibromatosis type 1 in the UK, focusing on the role that appearance plays in this experience. Background: neurofibromatosis type 1 is a genetic condition, which is highly variable and unpredictable. It can result in varying degrees of visible difference (disfigurement). Both the effect of NF1 on appearance and its uncertainty can prove particularly difficult for those affected. However, very little research to date has investigated the psychosocial impact of neurofibromatosis type 1 on young people or their experiences of managing it. Design: Exploratory qualitative interview study. Methods: Nine young people aged 14-24, with a confirmed diagnosis of neurofibromatosis type 1, took part in semi-structured interviews between March-September 2011. Interview transcripts were thematically analysed. Findings: Three key themes were identified from the data: (1) 'Different things to different people' reflecting the variability in the condition; (2) 'Relationships and reactions' relating to individuals' social experience; and (3) 'Understanding and misunderstanding' reflecting participants' experiences with organizations and social structures. Conclusions: Findings suggest a need for further research to explore young people's adaptation and management of neurofibromatosis type 1. In particular, raising awareness and understanding of the condition among professionals and in the general public was an important issue for young people. In addition, access to trustworthy information about neurofibromatosis type 1 and practical advice to support adjustment to an altered appearance and managing stigma experiences are highlighted as areas to be considered further. © 2013 John Wiley & Sons Ltd

Hierarchical simulations of hybrid polymer-solid materials

Complex polymer-solid materials have gained a lot of attention during the last 2-3 decades due to the fundamental physical problems and the broad spectrum of technological applications in which they are involved. Therefore, significant progress concerning the simulations of such hybrid soft-hard nanostructured systems has been made in the last few years. Simulation techniques vary from quantum to microscopic (atomistic) up to mesoscopic (coarse-grained) level. Here we give a short overview of simulation approaches on model polymer-solid interfacial systems for all different levels of description. In addition, we also present a brief outlook concerning the open questions in this field, from the point of view of both physical problems and computational methodologies

ParaCrawl: Web-Scale Acquisition of Parallel Corpora

We report on methods to create the largest publicly available parallel corpora by crawling the web, using open source software. We empirically compare alternative methods and publish benchmark data sets for sentence alignment and sentence pair filtering. We also describe the parallel corpora released and evaluate their quality and their usefulness to create machine translation systems

A pair production telescope for medium-energy gamma-ray polarimetry

We describe the science motivation and development of a pair production telescope for medium-energy (∼5–200 MeV) gamma-ray polarimetry. Our instrument concept, the Advanced Energetic Pair Telescope (AdEPT), takes advantage of the Three-Dimensional Track Imager, a low-density gaseous time projection chamber, to achieve angular resolution within a factor of two of the pair production kinematics limit (∼0.6° at 70 MeV), continuum sensitivity comparable with the Fermi-LAT front detector (<3 × 10−6 MeV cm−2 s−1 at 70 MeV), and minimum detectable polarization less than 10% for a 10 mCrab source in 106 s.submittedVersionFil: Hunter, Stanley D. National Aeronautics and Space Administration. Goddard Space Flight Center; Estados Unidos de América.Fil: Bloser, Peter F. University of New Hampshire. Institute for the Study of Earth, Oceans, and Space. Space Science Center; Estados Unidos de América.Fil: Depaola, Gerardo Osvaldo. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Dion, Michael P. Department of Energy. Office of Science. Pacific Northwest National Laboratory; Estados Unidos de América.Fil: DeNolfo, Georgia A. National Aeronautics and Space Administration. Goddard Space Flight Center; Estados Unidos de América.Fil: Hanu, Andrei. National Aeronautics and Space Administration. Goddard Space Flight Center; Estados Unidos de América.Fil: Iparraguirre, Lorenzo Marcos. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Legere, Jason. University of New Hampshire. Institute for the Study of Earth, Oceans, and Space. Space Science Center; Estados Unidos de América.Fil: Longo, Francesco. Università Degli Studi de Trieste. Dipartimento di fisica; Italia.Fil: McConnell, Mark L. University of New Hampshire. Institute for the Study of Earth, Oceans, and Space. Space Science Center; Estados Unidos de América.Fil: Nowicki, Suzanne F. National Aeronautics and Space Administration. Goddard Space Flight Center; Estados Unidos de América.Fil: Nowicki, Suzanne F. University of Maryland, Baltimore County. Department of Physics; Estados Unidos de América.Fil: Ryan, James M. University of New Hampshire. Institute for the Study of Earth, Oceans, and Space. Space Science Center; Estados Unidos de América.Fil: Son, Seunghee. National Aeronautics and Space Administration. Goddard Space Flight Center; Estados Unidos de América.Fil: Son, Seunghee. University of Maryland, Baltimore County. Department of Physics; Estados Unidos de América.Fil: Stecker, Floyd W. National Aeronautics and Space Administration. Goddard Space Flight Center; Estados Unidos de América.Física de Partículas y Campo

A Strategy of Underexpansion and Ad Hoc Post-Dilation of Balloon-Expandable Transcatheter Aortic Valves in Patients at Risk of Annular Injury Favorable Mid-Term Outcomes

AbstractObjectivesThe aim of this study was to evaluate a strategy of intentional underexpansion of excessively oversized balloon-expandable transcatheter heart valves (THVs) in terms of clinical outcomes, valve function, and frame durability at 1 year.BackgroundTranscatheter aortic valve replacement requires the selection of an optimally sized THV to ensure paravalvular sealing and fixation without risking annular injury. However, some patients have “borderline” annular dimensions that require choosing between a THV that may be too small or another that may be too large.MethodsWe evaluated 47 patients at risk of annular injury who underwent transcatheter aortic valve replacement (TAVR) with an oversized, but deliberately underexpanded, THV followed by post-dilation if required. Clinical evaluation, echocardiography, and cardiac computed tomography were performed pre-TAVR, post-TAVR, and at 1 year.ResultsDeployment of oversized THVs with modest underfilling of the deployment balloon (<10% by volume) was not associated with significant annular injury. Paravalvular regurgitation was mild or less in 95.7% of patients, with post-dilation required in 10.7%. THV hemodynamic function was excellent and remained stable at 1 year. Computed tomography documented stent frame circularity in 87.5%. Underexpansion was greatest within the intra-annular THV inflow (stent frame area 85.8% of nominal). There was no evidence of stent frame recoil, deformation, or fracture at 1 year.ConclusionsIn carefully selected patients with borderline annulus dimensions and in whom excessive oversizing of a balloon-expandable SAPIEN XT valve (Edwards Lifesciences, Inc., Irvine, California) is a concern, a strategy of deliberate underexpansion, with ad hoc post-dilation, if necessary, may reduce the risk of annular injury without compromising valve performance

Regional Systems of Care to Optimize Outcomes in Patients Undergoing Transcatheter Aortic Valve Replacement

AbstractObjectivesThis study sought to describe the development of a multicenter, transcatheter aortic valve replacement program and regional systems of care intended to optimize coordinated, efficient, and appropriate delivery of this new therapy.BackgroundTranscatheter aortic valve replacement (TAVR) has become an accepted treatment option for patients with severe aortic stenosis who are at high surgical risk. Regional systems of care have led to improvements in outcomes for patients undergoing intervention for myocardial infarction, cardiac arrest, and stroke. We implemented a regional system of care for patients undergoing TAVR in British Columbia, Canada.MethodsWe describe a prospective observational cohort of 583 patients who underwent TAVR in British Columbia between 2012 and 2014. Regionalization of TAVR care in British Columbia refers to a centrally coordinated, funded, and evaluated program led by a medical director and a multidisciplinary advisory group that oversees planning, access to care, and quality of outcomes at the 4 provincial sites. Risk-stratified case selection for transfemoral TAVR is performed by heart teams at each site on the basis of consensus provincial indications. Referrals for lower volume and more complicated TAVR, including nontransfemoral access and valve-in-valve procedures, are concentrated at a single site. In-hospital and 30-day outcomes are reported.ResultsThe median age was 83 years (interquartile range [IQR]: 78 to 87 years) and median STS score was 6% (IQR: 4% to 8%). Transfemoral access was performed in 499 (85.6%) cases and nontransfemoral in 84 (14.4%). Transcatheter valve-in-valve procedures in for failed bioprosthetic valves were performed in 43 patients (7.4%). A balloon-expandable valve was inserted in 386 (66.2%) and a self-expanding valve in 189 (32.4%). All-cause 30-day mortality was 3.5%. All-cause in-hospital mortality and disabling stroke occurred in 3.1% and 1.9%, respectively. Median length of stay was 3 days (IQR: 3 to 6 days), with 92.8% of patients discharged directly home.ConclusionsThis experience demonstrates the potential benefits of a regional system of care for TAVR. Excellent outcomes were demonstrated: most patients had short in-hospital stays and were discharged directly home

Western Cultural Identification Explains Variations in the Objectification Model for Eating Pathology Across Australian Caucasians and Asian Women

Objective: To assess differences in trait objectifying measures and eating pathology between Australian Caucasians and Asian women living in Australia and in Hong Kong with high and low levels of western cultural identification (WCI) and to see if exposure to objectifying images had an effect on state-objectification. A further aim was to assess using path analyses whether an extended version of the objectification model, including thin-ideal internalization, differed depending on the level of WCI. Method: A total of 424 participants comprising 162 Australian Caucasians and 262 Asians (n = 183 currently residing in Australia and n = 79 living in Hong Kong) took part in the study. Of the overall Asian sample, 133 individuals were classified as high-WCI and 129 participants as low-WCI. Participants were randomly allocated into one of two conditions, presenting either objectifying images of attractive and thin Asian and Caucasian female models (objectification group, n = 204), or showing neutral images of objects (e.g., chairs, tables; control group, n = 220). Subsequently, participants were asked to complete a series of questionnaires assessing objectification processes and eating pathology. Results: Findings revealed that the Caucasian group presented with significantly higher internalization and body surveillance scores than either of the two Asian groups and also revealed higher scores on trait-self-objectification than the low-WCI Asian sample. As regards to the effects of objectifying images on state self-objectification, we found that ratings were higher after exposure to women than to control objects for all groups. Finally, multi-group analyses revealed that our revised objectification model functioned equally across the Caucasian and the high-WCI Asian group, but differed between the Caucasian and the low-WCI Asian group. Conclusion: Our findings outline that individuals with varying levels of WCI might respond differently to self-objectification processes. Levels of WCI should therefore be taken into consideration when working with women from different cultural backgrounds