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Stellar Dynamical Modeling - Accuracy of 3D Density Estimation for Edge-on Axisymmetric Galaxies
No full textFrom Rybicki’s analysis using the Fourier slice theorem, mathematically it is possi-ble to reproduce uniquely an edge-on axisymmetric galaxy’s 3D light distribution from its 2Dsurface brightness. Utilizing galaxies from a cosmological simulation, we examine the abil-ity of Syer and Tremaine’s made-to-measure method and Schwarzschild’s method for stellardynamical modeling to do so for edge-on oblate axisymmetric galaxies. Overall, we find thatthe methods do not accurately recover the 3D distributions, with the made-to-measure methodproducing more accurate estimates than Schwarzschild’s method. Our results have implica-tions broader than just luminosity density, and affect other luminosity-weighted distributionswithin galaxies, for example, age and metallicity
The importance of keratinocyte-dendritic cell interactions in understanding fragrance allergy
No full textEfficient Multi-Objective Gans for Image Restoration
No full textGenerative adversarial networks (GANs) have been widely adopted in many image processing tasks including restoration. In order to further improve quality of generated images, the training objective function needs to incorporate more constraints in addition to the adversarial loss. It can be straightforward to combine various losses in a linear fashion. However, hyperparameter fine-tuning and non-convex loss optimization are challenging problems when combining cost functions in such a manner. Here, we propose an efficient formulation of multiple loss components for training GANs. The proposed method, termed HypervolGAN, not only provides an efficient alternative for simultaneous cost optimization, but also boosts model performance in terms of improving generated image quality without excess computation. We further introduce two image-quality-measure based loss components to the GANs specifically for image restoration. Extensive evaluations and results on various benchmark datasets validate the effectiveness of the proposed methods
Effect of 3d/4p Mixing on 1s2p Resonant Inelastic X-ray Scattering: Electronic Structure of oxo-bridged Iron Dimers
No full text1s2p resonant inelastic x-ray scattering (1s2p RIXS) has proven successful in the determination of the differential orbital covalency (DOC, the amount of metal vs. ligand character in each d molecular orbital) of highly covalent centrosymmetric iron environments including heme models and enzymes. However, many reactive intermediates have non-centrosymmetric environments, e.g. the presence of strong metal-oxo bonds, which results in the mixing of metal 4p character into the 3d orbitals. This leads to significant intensity enhancement in the metal K-pre-edge and as shown here, the associated 1s2p RIXS features, which impact their insight into electronic structure. Binuclear oxo bridged high spin Fe(III) complexes are used to determine the effects of 4p mixing on 1s2p RIXS spectra. In addition to developing the analysis of 4p mixing on K-edge XAS and 1s2p RIXS data, this study explains the selective nature of the 4p mixing that also enhances the analysis of L-edge XAS intensity in terms of DOC. These 1s2p RIXS biferric model studies enable new structural insight from related data on peroxo bridged biferric enzyme intermediates. The dimeric nature of the oxo bridged Fe(III) complexes further results in ligand-to-ligand interactions between the Fe(III) sites and angle dependent features just above the pre-edge that reflect the superexchange pathway of the oxo bridge. Finally, we present a methodology that enables DOC to be obtained when L-edge XAS is inaccessible and only 1s2p RIXS experiments can be performed as in many metalloenzyme intermediates in solution
Co-infection in critically ill patients with COVID-19 An observational cohort study from England
No full textObjective: To describe the incidence and nature of co-infection in critically ill adults with COVID-19 infection in England. Methods: A retrospective cohort study of adults with COVID-19 admitted to seven intensive care units (ICUs) in England up to 18 May 2020, was performed. Patients with completed ICU stays were included. The proportion and type of organisms were determined at <48 and >48 hours following hospital admission, corresponding to community and hospital-acquired coinfections. Results: Of 254 patients studied (median age 59 years (IQR 49-69); 64.6% male), 139 clinically significant organisms were identified from 83(32.7%) patients. Bacterial co-infections were identified within 48 hours of admission in 14(5.5%) patients; the commonest pathogens were Staphylococcus aureus (four patients) and Streptococcus pneumoniae (two patients). The proportion of pathogens detected increased with duration of ICU stay, consisting largely of Gram-negative bacteria, particularly Klebsiella pneumoniae and Escherichia coli. The coinfection rate >48 hours after admission was 27/1000 person-days (95% CI 21.3-34.1). Patients with co-infections were more likely to die in ICU (crude OR 1.78,95% CI 1.03-3.08, p=0.04) compared to those without co-infections. Conclusion: We found limited evidence for community-acquired bacterial co-infection in hospitalised adults with COVID-19, but a high rate of Gram-negative infection acquired during ICU stay
Sequence-Selective Decapeptide Synthesis by the Parallel Operation of Two Artificial Molecular Machines
No full textWe report on the preparation of a decapeptide through the parallel operation of two rotaxane-based molecular machines. The synthesis proceeds in four stages: (1) simultaneous operation of two molecular peptide synthesizers in the same reaction vessel; (2) selective residue activation of short-oligomer intermediates; (3) ligation; (4) product release. Key features of the machine design include: (a) selective transformation of a thioproline building block to a cysteine (once it has been incorporated into a hexapeptide intermediate by one molecular machine); (b) amacrocycle-peptide hydrazine linkage (as part of the second machine) to differentiate the intermediates and enable their directional ligation; and (c) incorporation of a Glu residue in the assembly module of one machine to enable release of the final product while simultaneously removing part of the assembly machinery from the product. The two molecular machines participate in the synthesis of a product that is beyond the capability ofindividual small-molecule machines, in a manner reminiscent of the ligation and post-translational modification of proteins in biology
Development of a method for generating SNP interaction-aware polygenic risk scores for radiotherapy toxicity
No full textAimTo identify the effect of single nucleotide polymorphism (SNP) interactions on the risk of toxicity following radiotherapy (RT) for prostate cancer (PCa) and propose a new method for polygenic risk score incorporating SNP-SNP interactions (PRSi).Materials and MethodsAnalysis included the REQUITE PCa cohort that received external beam RT and was followed for 2 years. Late toxicity endpoints were: rectal bleeding, urinary frequency, haematuria, nocturia, decreased urinary stream. Among 43 literature-identified SNPs, the 30% most strongly associated with each toxicity were tested. SNP-SNP combinations (named SNP-allele sets) seen in ≥10% of the cohort were condensed into risk (RS) and protection (PS) scores, respectively indicating increased or decreased toxicity risk. Performance of RS and PS was evaluated by logistic regression. RS and PS were then combined into a single PRSi evaluated by area under the receiver operating characteristic curve (AUC).ResultsAmong 1,387 analysed patients, toxicity rates were 11.7% (rectal bleeding), 4.0% (urinary frequency), 5.5% (haematuria), 7.8% (nocturia) and 17.1% (decreased urinary stream). RS and PS combined 8 to 15 different SNP-allele sets, depending on the toxicity endpoint. Distributions of PRSi differed significantly in patients with/without toxicity with AUCs ranging from 0.61 to 0.78. PRSi was better than the classical summed PRS, particularly for the urinary frequency, haematuria and decreased urinary stream endpoints.ConclusionsOur method incorporates SNP-SNP interactions when calculating PRS for radiotherapy toxicity. Our approach is better than classical summation in discriminating patients with toxicity and should enable incorporating genetic information to improve normal tissue complication probability models.<br/
Creating and evaluating transition from primary to high school utilising children’s rights.
No full textThe United Nations Convention on the Rights of the Child (UNCRC) sets out a series of rights for children. UNICEF has developed a Rights Respecting Schools Award (RRSA) through which schools can embed a whole-school approach to the UNCRC. This research used action research in an RRSA primary school to create and evaluate a rights-based transition process for a cohort of Year 6 pupils (10-11 years old). Data were collected from a questionnaire developed with pupils, a researcher diary, a staff focus group and a group interview with four pupils (11-12 years old) in their first term at high school following the rights-based transition. The utility of embedding rights in the transition process to support preparation and transfer of rights is identified, as is the importance of a visible rights framework to enable pupils to continue to promote and work towards rights realisation throughout transition and at their new setting
Spaces of Harassment: A Multilevel Analysis of the Role of Community Ethnic Composition, Segregation and Social Disorganisation Among Ethnic Minorities in Britain
No full textThis paper examines the community-level drivers of ethnic minorities' experiences of harassment in Britain, particularly the role of community ethnic structure (ethnic composition, ethnic segregation and ethnic-change), socio-economic disadvantage, and residential stability. Drawing on an ethnic minority-booster sample of a large-scale UK panel dataset, we address several potential shortcomings with prior analyses to make novel contributions, including taking a multilevel approach, using self-reported harassment data and not police statistics, testing across multiple geographic-scales, and measuring both actual harassment experiences and fear of future harassment. Key findings suggest minorities in areas with a higher share of Whites report a higher likelihood of harassment and that living in more residentially segregated areas increases minorities’ likelihoods of harassment. We also find strong evidence that socio-economic disadvantage and residential instability foster harassment. We find that these same community-level drivers are also significant for minorities’ fear of harassment; in part, because experiences of harassment affect the victim’s fear of future harassment, but also because harassment experiences spill over to impact fear among a victim’s close social contacts. These findings have important implications for the theorising of harassment and support the inclusion of community-level measures in national policy to reduce harassment
Biochemical Functionalization of Graphene Oxide for Directing Stem Cell Differentiation
No full textThe regeneration of peripheral nerve tissue is crucial in the treatment of peripheral nerve trauma. In recent years, there has been increased focus on biomaterial scaffolds which can deliver stem cells, direct differentiation to the desired lineage and guide tissue regeneration at the site of injury. Here, we report on a graphene oxide (GO) scaffold which has been chemically functionalised to direct the differentiation of adipose-derived mesenchymal stem cells towards the neuroglial lineage and maintain the viability of differentiated cells. A comparison is made between substrates of GO, reduced GO and a peptide (IKVAV) functionalised GO in comparison to standard tissue culture glass. Our results show that the graphene substrates are highly biocompatible, and the IKVAV functionalised substrates are more effective in directing stem cell differentiation towards neuroglial phenotypes compared to glass and other graphene substrates. Furthermore, GO-IKVAV substrates showed increased neuronal attachment and neurons grown on GO-IKVAV sprouted longer neurites. These results suggest that graphene can be rationally functionalised to direct stem-cell differentiation and that functionalised GO could provide a viable scaffold in regenerative therapies of peripheral nerve injuries and disorders