2,487 research outputs found
High surface area, emulsion-templated carbon foams by activation of polyHIPEs derived from Pickering emulsions.
Carbon foams displaying hierarchical porosity and excellent surface areas of >1400 m2/g can be produced by the activation of macroporous poly(divinylbenzene). Poly(divinylbenzene) was synthesized from the polymerization of the continuous, but minority, phase of a simple high internal phase Pickering emulsion. By the addition of KOH, chemical activation of the materials is induced during carbonization, producing Pickering-emulsion templated carbon foams, or carboHIPEs, with tailorable macropore diameters and surface areas almost triple that of those previously reported. The retention of the customizable, macroporous open-cell structure of the poly(divinylbenzene) precursor and the production of a large degree of microporosity during activation leads to tailorable carboHIPEs with excellent surface areas
Using Supervised Principal Components Analysis to Assess Multiple Pollutant Effects
BACKGROUND: Many investigations of the adverse health effects of multiple air pollutants analyze the time series involved by simultaneously entering the multiple pollutants into a Poisson log-linear model. This method can yield unstable parameter estimates when the pollutants involved suffer high intercorrelation; therefore, traditional approaches to dealing with multicollinearity, such as principal component analysis (PCA), have been promoted in this context. OBJECTIVES: A characteristic of PCA is that its construction does not consider the relationship between the covariates and the adverse health outcomes. A refined version of PCA, supervised principal components analysis (SPCA), is proposed that specifically addresses this issue. METHODS: Models controlling for long-term trends and weather effects were used in conjunction with each SPCA and PCA to estimate the association between multiple air pollutants and mortality for U.S. cities. The methods were compared further via a simulation study. RESULTS: Simulation studies demonstrated that SPCA, unlike PCA, was successful in identifying the correct subset of multiple pollutants associated with mortality. Because of this property, SPCA and PCA returned different estimates for the relationship between air pollution and mortality. CONCLUSIONS: Although a number of methods for assessing the effects of multiple pollutants have been proposed, such methods can falter in the presence of high correlation among pollutants. Both PCA and SPCA address this issue. By allowing the exclusion of pollutants that are not associated with the adverse health outcomes from the mixture of pollutants selected, SPCA offers a critical improvement over PCA
Current quark mass dependence of nucleon magnetic moments and radii
A calculation of the current-quark-mass-dependence of nucleon static
electromagnetic properties is necessary in order to use observational data as a
means to place constraints on the variation of Nature's fundamental parameters.
A Poincare' covariant Faddeev equation, which describes baryons as composites
of confined-quarks and -nonpointlike-diquarks, is used to calculate this
dependence The results indicate that, like observables dependent on the
nucleons' magnetic moments, quantities sensitive to their magnetic and charge
radii, such as the energy levels and transition frequencies in Hydrogen and
Deuterium, might also provide a tool with which to place limits on the allowed
variation in Nature's constants.Comment: 23 pages, 2 figures, 4 tables, 4 appendice
A proton-cyclotron wave storm generated by unstable proton distribution functions in the solar wind
We use audification of 0.092 s cadence magnetometer data from the Wind spacecraft to identify waves with amplitudes >0.1 nT near the ion gyrofrequency (~0.1 Hz) with duration longer than 1 hr during 2008. We present one of the most common types of event for a case study and find it to be a proton-cyclotron wave storm, coinciding with highly radial magnetic field and a suprathermal proton beam close in density to the core distribution itself. Using linear Vlasov analysis, we conclude that the long-duration, large-amplitude waves are generated by the instability of the proton distribution function. The origin of the beam is unknown, but the radial field period is found in the trailing edge of a fast solar wind stream and resembles other events thought to be caused by magnetic field footpoint motion or interchange reconnection between coronal holes and closed field lines in the corona
Bicuspid stenotic aortic valves: clinical characteristics and morphological assessment using MRI and echocardiography
Background Bicuspid aortic valve (BAV) is one of the most common congenital heart defects with a population prevalence of 0.5% to 1.3%. Identifying patients with BAV is clinically relevant because BAV is associated with aortic stenosis, endocarditis and ascending aorta pathology. Methods and Results Patients with severe aortic stenosis necessitating aortic valve replacement surgery were included in this study. All dissected aortic valves Were stored in the biobank of the University Medical Centre Utrecht. Additionally to the morphological assessment of the aortic valve by the surgeon and pathologist, echocardiographic and magnetic resonance imaging (MRI) images were evaluated. A total of 80 patients were included of whom 32 (40%) were diagnosed with BAV by the surgeon (gold standard). Patients with BAV were significantly younger (55 vs 71 years) and were more frequently male. Notably, a significant difference was found between the surgeon and pathologist in determining valve morphology. MRI was performed in 33% of patients. MRI could assess valve morphology in 96% vs 73% with echocardiography. The sensitivity of MRI for BAV in a population of patients with severe aortic stenosis was higher than echocardiography (75% vs 55%), whereas specificity was better with the latter (91% vs 79%). Typically, the ascending aorta was larger in patients with BAV. Conclusion Among unselected patients with severe aortic valve stenosis, a high percentage of patients with BAV were found. Imaging and assessment of the aortic valve morphology when stenotic is challengin
Economic evaluation alongside pragmatic randomised trials: developing a standard operating procedure for clinical trials units
<p>Abstract</p> <p>Background</p> <p>There is wide recognition that pragmatic randomised trials are the best vehicle for economic evaluation. This is because trials provide the best chance of ensuring internal validity, not least through the rigorous prospective collection of patient-specific data. Furthermore the marginal cost of collecting economic data alongside clinical data is typically modest. UK Clinical Research Collaboration (UKCRC) does not require a standard operating procedure (SOP) for economic evaluation as a prerequisite for trial unit registration. We judge that such a SOP facilitates the integration of health economics into trials.</p> <p>Methods</p> <p>A collaboration between health economists and trialists at Bangor University led to the development of a SOP for economic evaluation alongside pragmatic trials, in addition to the twenty SOPs required by UKCRC for registration, which include randomisation, data management and statistical analysis.</p> <p>Results</p> <p>Our recent telephone survey suggests that no other UKCRC-registered trials unit currently has an economic SOP.</p> <p>Conclusion</p> <p>We argue that UKCRC should require, from all Trials Units undertaking economic evaluation and seeking registration or re-registration, a SOP for economic evaluation as one of their portfolio of supporting SOPs.</p
Beyond the Insider—Outsider Perspective: The Study of Religion as a Study of Discourse Construction
This essay reflects on contemporary theorizing of religion which embodies an explicit critique of the imperial project, seeing that by most common consent the scholarly disciplinary field of religious studies (history of religion, phenomenology of religion, Religionswissenschaft) is a late nineteenth century invention that coincides with the emergence of anthropology and ethnography as epiphenomena of the colonial project (whether as Orientalism or as exoticism the Other is rendered manageable subjects). The scholarly study of religion is, therefore, simultaneously a study of the history of theory and concept formation, and the social, cultural, and political work performed by such study and theorizing. The metatheory of the study of religion is a main focus of the essay. Alongside that, the essay focuses more pointedly on the concept of discourse, and considers the extraordinary situation where the same methodological vocabulary that functions in religious studies also functions in critical theological studies, which relativizes the division of ‘insider’ and ‘outsider’ perspectives. Yet both are conventionally practised either in isolation from each other as distinct theoretical and disciplinary bounded/defined study fields, or—the other and almost direct opposite—religious studies being performed in the context of theological study, situated in and offered by theological faculties. An overview of recent debates in the field of religious studies serves to highlight the continued struggle to demarcate the boundaries between the study of religion and the study of theology—in some of the recent, very strident debates mainstream religious studies is labelled as nothing more than theology. This contribution, then, aims at a kind of metatheoretical reflection on the study of religion and theology both as discourses that serve mythmaking, identity formation, culturally strategic purposes. That is, from the discourse perspective that is proposed here, it is possible to move beyond the definitional divide between religious studies and theology—even beyond ‘religion’ itself—to focus on the mundanely material practices that constitute that which is called religion. In the way in which the terms are used it is clear that the terminologies themselves bear the imprint of historical social discourses that occasioned the rise of their use. This essay, then, is something of a metacritique of the language of the study of religion—beyond religion, and beyond the study of religion and theology
Recognition memory, self-other source memory, and theory-of-mind in children with autism spectrum disorder.
This study investigated semantic and episodic memory in autism spectrum disorder (ASD), using a task which assessed recognition and self-other source memory. Children with ASD showed undiminished recognition memory but significantly diminished source memory, relative to age- and verbal ability-matched comparison children. Both children with and without ASD showed an “enactment effect”, demonstrating significantly better recognition and source memory for self-performed actions than other-person-performed actions. Within the comparison group, theory-of-mind (ToM) task performance was significantly correlated with source memory, specifically for other-person-performed actions (after statistically controlling for verbal ability). Within the ASD group, ToM task performance was not significantly correlated with source memory (after controlling for verbal ability). Possible explanations for these relations between source memory and ToM are considered
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Hyperactivation of HUSH complex function by Charcot-Marie-Tooth disease mutation in MORC2
Dominant mutations in the gene have recently been shown to cause axonal Charcot–Marie–Tooth (CMT) disease, but the cellular function of MORC2 is poorly understood. Here, through a genome-wide CRISPR–Cas9-mediated forward genetic screen, we identified as an essential gene required for epigenetic silencing by the HUSH complex. HUSH recruits MORC2 to target sites in heterochromatin. We exploited a new method, differential viral accessibility (DIVA), to show that loss of MORC2 results in chromatin decompaction at these target loci, which is concomitant with a loss of H3K9me3 deposition and transcriptional derepression. The ATPase activity of MORC2 is critical for HUSH-mediated silencing, and the most common alteration affecting the ATPase domain in CMT patients (p.Arg252Trp) hyperactivates HUSH-mediated repression in neuronal cells. These data define a critical role for MORC2 in epigenetic silencing by the HUSH complex and provide a mechanistic basis underpinning the role of mutations in CMT disease.This work was supported by the Wellcome Trust, through a Principal Research Fellowship to P.J.L. (101835/Z/13/Z), a Senior Research Fellowship to Y.M. (101908/Z/13/Z), a Sir Henry Wellcome Postdoctoral Fellowship to R.T.T. (201387/Z/16/Z) and a PhD studentship to I.A.T., and by the BBSRC, through a Future Leader Fellowship to C.H.D. I.A.T. is supported as a Damon Runyon Fellow by the Damon Runyon Cancer Research Foundation (DRG-2277-16). The CIMR is in receipt of a Wellcome Trust strategic award
A pragmatic randomised controlled trial of healing therapy in a gastroenterology outpatient setting
Introduction
To determine the benefits of healing therapy (spiritual healing) as an adjunct to conventional management in irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD).
Methods
200 outpatients with IBS or IBD were randomised to either conventional treatment (control) or conventional plus five sessions of healing therapy (intervention). After 12 weeks controls also had healing therapy. Outcomes used were, the Measure Yourself Medical Outcomes Profile (MYMOP). IBS-QOL, IBDQ, and symptom measures.
Results
There was a significant improvement in the MYMOP score at week 6 (p < 0.001) which was maintained to week 12 (p < 0.001) and 24 (p < 0.001). Improvements in MYMOP were significantly greater in the intervention group at both 6 (p < 0.001) and 12 weeks (p < 0.001) with effect sizes of 0.7 (95% CI: 0.4–1.1) and 0.8 (95% CI: 0.4–1.2). Condition-specific data for IBS showed that most QoL dimensions had a significant minimum 10-point score improvement at 6 and 12 weeks. The overall score improvement was 12.9 units at week 6 (p < 0.001), 12.4 units at week 12 (p < 0.001) and 13.8 units at week 24 (p < 0.001). In IBD there was also similar score improvement, but only up to week 12 were there associations of improved social and bowel functions (p < 0.001, respectively). Between group differences were identified for QoL scores in IBS at both week 6 (p < 0.001) and 12 (p < 0.001) but only for week 12 (p < 0.001) in the IBD group.
Conclusions
The addition of healing therapy to conventional treatment was associated with improvement in symptoms and QoL in IBS, and to a lesser extent in IBD
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