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Improving Holographic Search Algorithms using Sorted Pixel Selection
Traditional search algorithms for computer hologram generation such as Direct Search and Simulated Annealing offer some of the best hologram qualities at convergence when compared to rival approaches. Their slow generation times and high processing power requirements mean, however, that they see little use in performance critical applications.
This paper presents the novel Sorted Pixel Selection (SPS) modification for Holographic Search Algorithms (HSAs) that offers Mean Square Error (MSE) reductions in the range of 14:7 19:2% for the test images used. SPS operates by substituting a weighted search selection procedure for
traditional random pixel selection processes. While small, the improvements seen are observed consistently across a wide range of test cases and require limited overhead for implementatio
Review of the prevalence of diabetic retinopathy in Indigenous Australians
Author version made available in accordance with Publisher copyright policy.The purpose of this review is to compare the prevalence of diabetic retinopathy (DR) between Indigenous and non-Indigenous Australians with Diabetes Mellitus (DM). Australian DR prevalence data from 6 Indigenous studies (n = 2865) and 5 non-Indigenous studies (n = 9801) conducted between 1985 and 2013 were included for analysis. Estimated prevalence of any DR among Indigenous Australians with DM was 23.4% compared with 28.9% for non-Indigenous Australians (χ2 = 26.9, P < 0.001). In studies performed after 1990, a significantly higher rate of diabetic macular edema was found in Indigenous compared with non-Indigenous Australians with DM (7.6% versus 4.9%, χ2 = 6.67, P = 0.01). Although there are limitations in comparing these studies, one explanation for the observed data could be a model in which Indigenous Australians are relatively resistant to early stage DR, but with a subset progressing to sight threatening DR due to individual genetic and environmental susceptibility factors coupled with poor glycemic control
The aesthetic appeal of auditory-visual synaesthetic perceptions in people without synaesthesia
The term 'visual music' refers to works of art in which both hearing and vision are directly or indirectly stimulated. Our ability to create, perceive, and appreciate visual music is hypothesised to rely on the same multisensory processes that support auditory-visual (AV) integration in other contexts. Whilst these mechanisms have been extensively studied, there has been little research on how these processes affect aesthetic judgments (of liking or preference). Studies of synaesthesia in which sound evokes vision and studies of cross-modal biases in non-synaesthetes have revealed non-arbitrary mappings between visual and auditory properties (eg high-pitch sounds being smaller and brighter). In three experiments, we presented members of the general population with animated AV clips derived from synaesthetic experiences and contrasted them with a number of control conditions. The control conditions consisted of the same clips rotated or with the colour changed, random AV pairings, or animated clips generated by non-synaesthetes. Synaesthetic AV animations were generally preferred over the control conditions. The results suggest that non-arbitrary AV mappings, present in the experiences of synaesthetes, can be readily appreciated by others and may underpin our tendency to engage with certain forms of art
Assessment of polygenic effects links primary open-angle glaucoma and age-related macular degeneration
This work is licensed under a Creative Commons Attribution 4.0 International License. The images
or other third party material in this article are included in the article’s Creative Commons license,
unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license,
users will need to obtain permission from the license holder to reproduce the material. To view a copy of this
license, visit http://creativecommons.org/licenses/by/4.0/Primary open-angle glaucoma (POAG) and age-related macular degeneration (AMD) are leading causes
of irreversible blindness. Several loci have been mapped using genome-wide association studies.
Until very recently, there was no recognized overlap in the genetic contribution to AMD and POAG.
At genome-wide significance level, only ABCA1 harbors associations to both diseases. Here, we
investigated the genetic architecture of POAG and AMD using genome-wide array data. We estimated
the heritability for POAG (h2
g = 0.42 ± 0.09) and AMD (h2
g = 0.71 ± 0.08). Removing known loci for
POAG and AMD decreased the h2
g estimates to 0.36 and 0.24, respectively. There was evidence for a
positive genetic correlation between POAG and AMD (rg = 0.47 ± 0.25) which remained after removing
known loci (rg = 0.64 ± 0.31). We also found that the genetic correlation between sexes for POAG was
likely to be less than 1 (rg = 0.33 ± 0.24), suggesting that differences of prevalence among genders may
be partly due to heritable factors
Progress and challenges in coupled hydrodynamic-ecological estuarine modeling
© The Author(s), 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Estuaries and Coasts 39 (2016): 311-332, doi:10.1007/s12237-015-0011-y.Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In this review, we present historical and modern perspectives on estuarine hydrodynamic and ecological modeling, consider model limitations, and address aspects of model linkage, skill assessment, and complexity. We discuss the balance between spatial and temporal resolution and present examples using different spatiotemporal scales. Finally, we recommend future lines of inquiry, approaches to balance complexity and uncertainty, and model transparency and utility. It is idealistic to think we can pursue a “theory of everything” for estuarine models, but recent advances suggest that models for both scientific investigations and management applications will continue to improve in terms of realism, precision, and accuracy.NKG, ALA, and RPS acknowledge
support from the USGS Coastal and Marine Geology Program.
DKR gratefully acknowledges support from NSF (OCE-1314642) and NIEHS (1P50-ES021923-01). MJB and JMPV gratefully acknowledge
support from NOAA NOS NCCOS (NA05NOS4781201 and
NA11NOS4780043). MJB and SJL gratefully acknowledge support from
the Strategic Environmental Research and Development Program—Defense
Coastal/Estuarine Research Program (RC-1413 and RC-2245)
Do obesity-promoting food environments cluster around socially disadvantaged schools in Glasgow, Scotland?
Increase in the consumption of food and drinks outside the home by adolescents and young people and associations with rising levels of obesity is a significant concern worldwide and it has been suggested that the food environment around schools may be a contributory factor. As few studies have explored this issue in a UK setting, we examined whether different types of food outlets are clustered around public secondary schools in Glasgow, and whether this pattern differed by social disadvantage. We found evidence of clustering of food outlets around schools but a more complex picture in relation to deprivation was observed. Across all schools there were numerous opportunities for pupils to purchase energy dense foods locally and the implications for policy are discussed
A large genome-wide association study of age-related macular degeneration highlights contributions of rare and common variants.
This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/ng.3448Advanced age-related macular degeneration (AMD) is the leading cause of blindness in the elderly, with limited therapeutic options. Here we report on a study of >12 million variants, including 163,714 directly genotyped, mostly rare, protein-altering variants. Analyzing 16,144 patients and 17,832 controls, we identify 52 independently associated common and rare variants (P < 5 × 10(-8)) distributed across 34 loci. Although wet and dry AMD subtypes exhibit predominantly shared genetics, we identify the first genetic association signal specific to wet AMD, near MMP9 (difference P value = 4.1 × 10(-10)). Very rare coding variants (frequency <0.1%) in CFH, CFI and TIMP3 suggest causal roles for these genes, as does a splice variant in SLC16A8. Our results support the hypothesis that rare coding variants can pinpoint causal genes within known genetic loci and illustrate that applying the approach systematically to detect new loci requires extremely large sample sizes.We thank all participants of all the studies included for enabling this research by their participation in these studies. Computer resources for this project have been provided by the high-performance computing centers of the University of Michigan and the University of Regensburg. Group-specific acknowledgments can be found in the Supplementary Note. The Center for Inherited Diseases Research (CIDR) Program contract number is HHSN268201200008I. This and the main consortium work were predominantly funded by 1X01HG006934-01 to G.R.A. and R01 EY022310 to J.L.H
Neighbourhood built environment associations with body size in adults:mediating effects of activity and sedentariness in a cross-sectional study of New Zealand adults
Background: The aim of this study was to determine the associations between body size and built environment walkability variables, as well as the mediating role of physical activity and sedentary behaviours with body size. Methods: Objective environment, body size (body mass index (BMI), waist circumference (WC)), and sedentary time and physical activity data were collected from a random selection of 2033 adults aged 20-65 years living in 48 neighbourhoods across four New Zealand cities. Multilevel regression models were calculated for each comparison between body size outcome and built environment exposure. Results and Discussion: Street connectivity and neighborhood destination accessibility were significant predictors of body size (1 SDchange predicted a 1.27 to 1.41 % reduction in BMI and a 1.76 to 2.29 % reduction in WC). Significantrelationships were also observed for streetscape (1 SD change predicted a 1.33 % reduction in BMI) anddwelling density (1 SD change predicted a 1.97 % reduction in BMI). Mediation analyses revealed asignificant mediating effect of physical activity on the relationships between body size and street connectivity and neighbourhood destination accessibility (explaining between 10.4 and 14.6 % of the total effect). No significant mediating effect of sedentary behaviour was found. Findings from this cross-sectional study of a random selection of New Zealand adults are consistent with international research. Findings are limited to individual environment features only; conclusions cannot be drawn about the cumulative and combined effect of individual features on outcomes. Conclusions: Built environment features were associated with body size in the expected directions. Objectively-assessed physical activity mediated observed built environment-body size relationships
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