808 research outputs found
Applications of Google Earth Engine in fluvial geomorphology for detecting river channel change
© 2020 The Authors. Cloud-based computing, access to big geospatial data, and virtualization, whereby users are freed from computational hardware and data management logistics, could revolutionize remote sensing applications in fluvial geomorphology. Analysis of multitemporal, multispectral satellite imagery has provided fundamental geomorphic insight into the planimetric form and dynamics of large river systems, but information derived from these applications has largely been used to test existing concepts in fluvial geomorphology, rather than for generating new concepts or theories. Traditional approaches (i.e., desktop computing) have restricted the spatial scales and temporal resolutions of planimetric river channel change analyses. Google Earth Engine (GEE), a cloud-based computing platform for planetary-scale geospatial analyses, offers the opportunity to relieve these spatiotemporal restrictions. We summarize the big geospatial data flows available to fluvial geomorphologists within the GEE data catalog, focus on approaches to look beyond mapping wet channel extents and instead map the wider riverscape (i.e., water, sediment, vegetation) and its dynamics, and explore the unprecedented spatiotemporal scales over which GEE analyses can be applied. We share a demonstration workflow to extract active river channel masks from a section of the Cagayan River (Luzon, Philippines) then quantify centerline migration rates from multitemporal data. By enabling fluvial geomorphologists to take their algorithms to petabytes worth of data, GEE is transformative in enabling deterministic science at scales defined by the user and determined by the phenomena of interest. Equally as important, GEE offers a mechanism for promoting a cultural shift toward open science, through the democratization of access and sharing of reproducible code.Natural Environment Research Council. Grant Number: NE/S00331
Instruments of RT-2 Experiment onboard CORONAS-PHOTON and their test and evaluation III: Coded Aperture Mask and Fresnel Zone Plates in RT-2/CZT Payload
Imaging in hard X-rays of any astrophysical source with high angular
resolution is a challenging job. Shadow-casting technique is one of the most
viable options for imaging in hard X-rays. We have used two different types of
shadow-casters, namely, Coded Aperture Mask (CAM) and Fresnel Zone Plate (FZP)
pair and two types of pixellated solid-state detectors, namely, CZT and CMOS in
RT-2/CZT payload, the hard X-ray imaging instrument onboard the CORONAS-PHOTON
satellite. In this paper, we present the results of simulations with different
combinations of coders (CAM & FZP) and detectors that are employed in the
RT-2/CZT payload. We discuss the possibility of detecting transient Solar
flares with good angular resolution for various combinations. Simulated results
are compared with laboratory experiments to verify the consistency of the
designed configuration.Comment: 27 pages, 16 figures, Accepted for publication in Experimental
Astronomy (in press
Nipple- and areola-sparing mastectomy for the treatment of breast cancer
The efficacy and safety of nipple-sparing mastectomy and areola-sparing mastectomy for the treatment of breast cancer are still questionable. It is estimated that the local recurrence rates following nipple-sparing mastectomy are very similar to breast-conserving surgery followed by radiotherapy.
To assess the efficacy and safety of nipple-sparing mastectomy and areola-sparing mastectomy for the treatment of ductal carcinoma in situ and invasive breast cancer in women.
We searched the Cochrane Breast Cancer Group's Specialized Register, the Cochrane Center Register of Controlled Trials (CENTRAL), MEDLINE (via PubMed), Embase (via OVID) and LILACS (via Biblioteca Virtual em Saúde [BVS]) using the search terms “nipple sparing mastectomy” and “areola-sparing mastectomy”. Also, we searched the World Health Organization's International Clinical Trials Registry Platform and ClinicalTrials.gov. All searches were conducted on 30th September 2014 and we did not apply any language restrictions.
Randomised controlled trials (RCTs) however if there were no RCTs, we expanded our criteria to include non-randomised comparative studies (cohort and case-control studies). Studies evaluated nipple-sparing and areola-sparing mastectomy compared to modified radical mastectomy or skin-sparing mastectomy for the treatment of ductal carcinoma in situ or invasive breast cancer.
Two review authors (BS and RR) performed data extraction and resolved disagreements. We performed descriptive analyses and meta-analyses of the data using Review Manager software. We used Cochrane's risk of bias tool to assess studies, and adapted it for non-randomised studies, and we evaluated the quality of the evidence using GRADE criteria.
We included 11 cohort studies, evaluating a total of 6502 participants undergoing 7018 procedures: 2529 underwent a nipple-sparing mastectomy (NSM), 818 underwent skin-sparing mastectomy (SSM) and 3671 underwent traditional mastectomy, also known as modified radical mastectomy (MRM). No participants underwent areola-sparing mastectomy. There was a high risk of confounding for all reported outcomes. For overall survival, the hazard ratio (HR) for NSM compared to SSM was 0.70 (95% CI 0.28 to 1.73; 2 studies; 781 participants) and the HR for NSM compared to MRM was 0.72 (95% CI 0.46 to 1.13; 2 studies, 1202 participants). Local recurrence was evaluated in two studies, the HR for NSM compared to MRM was 0.28 (95% CI 0.12 to 0.68; 2 studies, 1303 participants). The overall risk of complications was different in NSM when compared to other types of mastectomy in general (RR 0.10, 95% CI 0.01 to 0.82, 2 studies, P = 0.03; 1067 participants). With respect to skin necrosis, there was no evidence of a difference with NSM compared to other types of mastectomy, but the confidence interval was wide (RR 4.22, 95% CI 0.59 to 30.03, P = 0.15; 4 studies, 1948 participants). We observed no difference among the three types of mastectomy with respect to the risk of local infection (RR 0.95, 95% CI 0.44 to 2.09, P = 0.91, 2 studies; 496 participants). Meta-analysis was not possible when assessing cosmetic outcomes and quality of life, but in general the NSM studies reported a favourable aesthetic result and a gain in quality of life compared with the other types of mastectomy. The quality of evidence was considered very low for all outcomes due to the high risk of selection bias and wide confidence intervals.
The findings from these observational studies of very low-quality evidence were inconclusive for all outcomes due to the high risk of selection bias
Detecting and quantifying morphological change in tropical rivers using Google Earth Engine and image analysis techniques
Copyright © 2020 The Author(s). Various tools have been demonstrated that are capable of delineating and characterizing river channels, but efforts to scale these analyses up to multi-temporal, catchment-scale applications are in their infancy. Here, we use Google Earth Engine (GEE) to extract the active channel (including the wetted channel and unvegetated, alluvial deposits) from the Bislak and Cagayan Rivers in the Philippines. Using temporal composites of Landsat 5, 7 and 8 satellite imagery over ~30 years, the active channel is resolved at annual intervals. The active channel occurrence frequency is mapped using image analysis techniques to detect large-scale planimetric change. Quantification of active channel centerline change is achieved using the RivMAP toolbox. Over a 135 km reach of the Cagayan River, the average migration rate was 17.5 m.a-1 ranging from 7.7 m.a-1 in 1988 to 37.0 m.a-1 in 2005. The findings quantify patterns of dynamism in tropical river systems and demonstrate the utility of GEE in fluvial geomorphology applications
The systemic lupus erythematosus IRF5 risk haplotype is associated with systemic sclerosis
Systemic sclerosis (SSc) is a fibrotic autoimmune disease in which the genetic component plays an important role. One of the strongest SSc association signals outside the human leukocyte antigen (HLA) region corresponds to interferon (IFN) regulatory factor 5 (IRF5), a major regulator of the type I IFN pathway. In this study we aimed to evaluate whether three different haplotypic blocks within this locus, which have been shown to alter the protein function influencing systemic lupus erythematosus (SLE) susceptibility, are involved in SSc susceptibility and clinical phenotypes. For that purpose, we genotyped one representative single-nucleotide polymorphism (SNP) of each block (rs10488631, rs2004640, and rs4728142) in a total of 3,361 SSc patients and 4,012 unaffected controls of Caucasian origin from Spain, Germany, The Netherlands, Italy and United Kingdom. A meta-analysis of the allele frequencies was performed to analyse the overall effect of these IRF5 genetic variants on SSc. Allelic combination and dependency tests were also carried out. The three SNPs showed strong associations with the global disease (rs4728142: P = 1.34×10<sup>−8</sup>, OR = 1.22, CI 95% = 1.14–1.30; rs2004640: P = 4.60×10<sup>−7</sup>, OR = 0.84, CI 95% = 0.78–0.90; rs10488631: P = 7.53×10<sup>−20</sup>, OR = 1.63, CI 95% = 1.47–1.81). However, the association of rs2004640 with SSc was not independent of rs4728142 (conditioned P = 0.598). The haplotype containing the risk alleles (rs4728142*A-rs2004640*T-rs10488631*C: P = 9.04×10<sup>−22</sup>, OR = 1.75, CI 95% = 1.56–1.97) better explained the observed association (likelihood P-value = 1.48×10<sup>−4</sup>), suggesting an additive effect of the three haplotypic blocks. No statistical significance was observed in the comparisons amongst SSc patients with and without the main clinical characteristics. Our data clearly indicate that the SLE risk haplotype also influences SSc predisposition, and that this association is not sub-phenotype-specific
Experiencing sense of place in virtual and physical Avebury.
This paper discusses the findings from a project to construct a simulation of Avebury henge, a Late Neolithic/ Early Bronze Age monument in SW Britain, in a 3D, virtual world environment. The aims of the study were to explore the archaeological research and interpretation necessary to plan and construct such a simulation in an interactive, online environment, to identify which aspects of visualisation and soundscape design appear to have the greatest impact upon users’ sense of place in the virtual simulation and to explore the experiences of a small group of users in the virtual simulation and the effects of those experiences upon their sense of place at the physical site. The findings from this project demonstrated that in undertaking a simulation of an ancient site, a core set of sources need to be selected to create the main parts of the simulation. There is often much debate in archaeological literature regarding the way in which archaeological findings are interpreted, and a different virtual Avebury would be constructed if different interpretations had been chosen. Any simulation of an ancient site should therefore clearly recognise and state the basis upon which it has been designed. The evaluation showed that responses to virtual environments, and the resulting effect upon responses to physical environments, are complex and personal, resulting in a range of experiences and perceptions, suggesting that the range of users’ experiences might be a more significant issue than attempting to find any general consensus on user reactions to simulated ancient sites
Association between Serum Interleukin-6 Concentrations and Mortality in Older Adults: The Rancho Bernardo Study
Background: Interleukin-6 (IL-6) may have a protective role in acute liver disease but a detrimental effect in chronic liver disease. It is unknown whether IL-6 is associated with risk of liver-related mortality in humans. Aims: To determine if IL-6 is associated with an increased risk of all-cause, cardiovascular disease (CVD), cancer, and liverrelated mortality. Methods: A prospective cohort study included 1843 participants who attended a research visit in 1984–87. Multiple covariates were ascertained including serum IL-6. Multivariable-adjusted Cox proportional hazards regression analyses were used to examine the association between serum IL-6 as a continuous (log transformed) variable with all-cause, CVD, cancer, and liver-related mortality. Patients with prevalent CVD, cancer and liver disease were excluded for cause-specific mortality. Results: The mean (6 standard deviation) age and body-mass-index (BMI) of participants was 68 (610.6) years and 25 (63.7) Kg/m 2, respectively. During the 25,802 person-years of follow-up, the cumulative all-cause, CVD, cancer, and liverrelated mortality were 53.1 % (N = 978), 25.5%, 11.3%, and 1.3%, respectively. The median (6IQR) length of follow-up was 15.3610.6 years. In multivariable analyses, adjusted for age, sex, alcohol, BMI, diabetes, hypertension, total cholesterol, HDL, and smoking, one-SD increment in log-transformed serum IL-6 was associated with increased risk of all-cause, CVD, cancer, and liver-related mortality, with hazard ratios of 1.48 (95 % CI, 1.33–1.64), 1.38 (95 % CI, 1.16–1.65), 1.35 (95 % CI, 1.02–1.79)
The effects of stochastic resonance electrical stimulation and neoprene sleeve on knee proprioception
<p>Abstract</p> <p>Background</p> <p>A variety of knee injuries and pathologies may cause a deficit in knee proprioception which may increase the risk of reinjury or the progression of disease. Stochastic resonance stimulation is a new therapy which has potential benefits for improving proprioceptive function. The objective of this study was to determine if stochastic resonance (SR) stimulation applied with a neoprene sleeve could improve knee proprioception relative to a no-stimulation/no-sleeve condition (control) or a sleeve alone condition in the normal, healthy knee. We hypothesized that SR stimulation when applied with a sleeve would enhance proprioception relative to the control and sleeve alone conditions.</p> <p>Methods</p> <p>Using a cross-over within subject design, twenty-four healthy subjects were tested under four combinations of conditions: electrical stimulation/sleeve, no stimulation/sleeve, no stimulation/no sleeve, and stimulation/no sleeve. Joint position sense (proprioception) was measured as the absolute mean difference between a target knee joint angle and the knee angle reproduced by the subject. Testing was conducted during both partial-weight bearing (PWB) and non-weight bearing (NWB) tasks. Differences in joint position sense between the conditions were evaluated by repeated-measures analysis of variance testing.</p> <p>Results</p> <p>Joint position sense error during the stimulation/sleeve condition (2.48° ± 1.32°) was found to be more accurate (P < 0.05) relative to the control condition (3.35° ± 1.63°) in the PWB task. No difference in joint position sense error was found between stimulation/sleeve and sleeve alone conditions for the PWB task. Joint position sense error was not found to differ between any of the conditions for the NWB task.</p> <p>Conclusion</p> <p>These results suggest that SR electrical stimulation when combined with a neoprene sleeve is an effective modality for enhancement of joint proprioception in the PWB knee. We believe these results suggest the need for further study of the potential of SR stimulation to correct proprioceptive deficits in a clinical population with knee injury/pathology or in subjects at risk of injury because of a proprioceptive deficit.</p
The incidence and prevalence of diabetes in patients with serious mental illness in North West Wales: Two cohorts, 1875–1924 & 1994–2006 compared
<p>Abstract</p> <p>Background</p> <p>Against a background of interest in rates of diabetes in schizophrenia and related psychoses and claims that data from historical periods demonstrate a link that antedates modern antipsychotics, we sought to establish the rate of diabetes in first onset psychosis and subsequent prevalence in historical and contemporary cohorts.</p> <p>Methods</p> <p>Analysis of two epidemiologically complete databases of individuals admitted for mental illness. 3170 individuals admitted to the North Wales Asylum between 1875–1924 and tracked over 18,486 patient years and 394 North West Wales first admissions for schizophrenia and related psychoses between 1994 and 2006 and tracked after treatment.</p> <p>Results</p> <p>The prevalence of Type 2 diabetes among patients with psychoses at time of first admission in both historical and contemporary samples was 0%. The incidence of diabetes remained 0% in the historical sample throughout 15 years of follow-up but rose in the contemporary sample after 3, 5 and 6 years of treatment with an incidence rate double the expected population rate so that the 15 year prevalence is likely to be over 8%.</p> <p>Conclusion</p> <p>No association was found between diabetes and serious mental illness, but there may be an association between diabetes and treatment.</p
Proinflammatory genotype is associated with the frailty phenotype in the English Longitudinal Study of Ageing
Background: Frailty is a state of increased vulnerability to poor resolution of homeostasis after a stressor event, which increases the risk of adverse outcomes including falls, disability and death. The underlying pathophysiological pathways of frailty are not known but the hypothalamic–pituitary–adrenal axis and heightened chronic systemic inflammation appear to be major contributors. Methods: We used the English Longitudinal Study of Ageing dataset of 3160 individuals over the age of 50 and assessed their frailty status according to the Fried-criteria. We selected single nucleotide polymorphisms in genes involved in the steroid hormone or inflammatory pathways and performed linear association analysis using age and sex as covariates. To support the biological plausibility of any genetic associations, we selected biomarker levels for further analyses to act as potential endophenotypes of our chosen genetic loci. Results: The strongest association with frailty was observed in the Tumor Necrosis Factor (TNF) (rs1800629, P = 0.001198, β = 0.0894) and the Protein Tyrosine Phosphatase, Receptor type, J (PTPRJ) (rs1566729, P = 0.001372, β = 0.09397) genes. Rs1800629 was significantly associated with decreased levels of high-density lipoprotein (HDL) (P = 0.00949) and cholesterol levels (P = 0.00315), whereas rs1566729 was associated with increased levels of HDL (P = 0.01943). After correcting for multiple testing none of the associations remained significant. Conclusions: We provide potential evidence for the involvement of a multifunctional proinflammatory cytokine gene (TNF) in the frailty phenotype. The implication of this gene is further supported by association with the endophenotype biomarker results
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