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Density-based global sensitivity analysis of sheet-flow travel time: Kinematic wave-based formulations
Get PDF© 2017 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (February 2018) in accordance with the publisher’s archiving policyDespite advancements in developing physics-based formulations to estimate the sheet-flow travel time (), the quantification of the relative impacts of influential parameters on has not previously been considered. In this study, a brief review of the physics-based formulations to estimate including kinematic wave (K-W) theory in combination with Manning’s roughness (K-M) and with Darcy-Weisbach friction formula (K-D) over single and multiple planes is provided. Then, the relative significance of input parameters to the developed approaches is quantified by a density-based global sensitivity analysis (GSA). The performance of K-M considering zero-upstream and uniform flow depth (so-called K-M1 and K-M2), and K-D formulae to estimate the over single plane surface were assessed using several sets of experimental data collected from the previous studies. The compatibility of the developed models to estimate over multiple planes considering temporal rainfall distributions of Natural Resources Conservation Service, NRCS (I, Ia, II, and III) are scrutinized by several real-world examples. The results obtained demonstrated that the main controlling parameters of through K-D and K-M formulae are the length of surface plane (mean sensitivity index = 0.72) and flow resistance (mean = 0.52), respectively. Conversely, the flow temperature and initial abstraction ratio of rainfall have the lowest influence on (mean is 0.11 and 0.12, respectively). The significant role of the flow regime on the estimation of over a single and a cascade of planes are also demonstrated. Results reveal that the K-D formulation provides more precise over the single plane surface with an average percentage of error, APE equal to 9.23% (the APE for K-M1 and K-M2 formulae were 13.8%, and 36.33%, respectively). The superiority of Manning-jointed formulae in estimation of is due to the incorporation of effects from different flow regimes as flow moves downgradient that is affected by one or more factors including high excess rainfall intensities, low flow resistance, high degrees of imperviousness, long surfaces, steep slope, and domination of rainfall distribution as NRCS Type I, II, or III
Investigation of short tandem repeats in major depression using whole-genome sequencing data
Get PDF© 2017 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (February 2018) in accordance with the publisher’s archiving policyBackground
Major depressive disorder (MDD) is a leading contributor to global disease burden. Recent studies have shown that genetic factors play significant roles in the susceptibility to this condition; however, the underlying genetic basis currently remains largely unknown. Short tandem repeat (STR) has been proposed as an explanatory factor in the “missing heritability” of complex diseases or traits.
Methods
We investigated STR variations from 15 MDD patients and 10 ethnically matched healthy controls based on their deep whole-genome sequencing (WGS) data. The lobSTR software was used to computationally determine STRs.
Results
The results of the Mexican-American sample showed that STRs are significantly richer in healthy controls than in MDD cases on each of the 23 chromosomes (all false discovery rates, FDR P-values < 0.0062); while for the Australian of European-ancestry sample, there was no statistically significant STRs difference between MDD cases and controls.
Limitations
High quality WGS costs limited obtaining larger datasets.
Conclusions
This preliminary work is the first study that STR variations are applied to investigate MDD based on WGS data. The results on Mexican-American population may imply that within the same ancestry, targeted sequencing on a specific chromosome or region of genome would be sufficient for examining the relationship between STR and MDD. Further studies should examine larger sequencing datasets on other ethnic groups
Negative ion formation through dissociative electron attachment to the group IV tetrachlorides: Carbon tetrachloride, silicon tetrachloride and germanium tetrachloride
Get PDF© 2018 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license:http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 24 month embargo from date of publication (Jan 2018) in accordance with the publisher’s archiving policyThe current contribution constitutes the third and final part of our trilogy of papers on electron attachment reactions of the group IV tetrahalides; XY4 (X = C, Si, Ge and Y = F, Cl, Br). In this context we extend our previous studies on XF4 and XBr4 and report results for electron attachment to the tetrachlorides: CCl4, SiCl4 and GeCl4 in the incident electron energy range from about 0 to 10 eV. At the same time we give a summary of the currently available literature on electron interactions with those latter compounds. Upon electron attachment the formation of Cl−, XCl3−, XCl2− and Cl2− is observed from all the tetrachlorides, and additionally the molecular anion SiCl4− is observed from SiCl4. The main DEA contributions are observed through narrow, threshold peaks (at 0 eV) and we attribute these features to single particle resonances associated with the a1 symmetry LUMOs of those compounds. Contributions from another low-lying resonance, which we assign as a 2T2 shape resonance associated with the t2 symmetry LUMO+1, is also observed in the ion yield curves for all the tetrachlorides. The energy of the peak position of those contributions varies in the range from about 1 to 2 eV, depending on the compound and the fragment formed. In addition to these low energy contributions, higher energy, fairly broad, features are observed for all the tetrachlorides. These contributions exhibit a peak in the energy range between 5 and 8 eV, again depending on the compound and the fragment formed. Further to the experimental data, we report DFT and coupled cluster calculations on the thermochemical thresholds for the individual fragments as well as the respective bond dissociation energies and electron affinities. These calculated values are compared with the experimental appearance energies and literature values, where they are available
Testosterone Pathway Genetic Polymorphisms in Relation to Primary Open-Angle Glaucoma: An Analysis in Two Large Datasets
Get PDFCopyright 2018 The Authors This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. Attribution-NonCommercial-NoDerivativesPurpose: Sex hormones may be associated with primary open-angle glaucoma (POAG), although the mechanisms are unclear. We previously observed that gene variants involved with estrogen metabolism were collectively associated with POAG in women but not men; here we assessed gene variants related to testosterone metabolism collectively and POAG risk.
Methods: We used two datasets: one from the United States (3853 cases and 33,480 controls) and another from Australia (1155 cases and 1992 controls). Both datasets contained densely called genotypes imputed to the 1000 Genomes reference panel. We used pathway- and gene-based approaches with Pathway Analysis by Randomization Incorporating Structure (PARIS) software to assess the overall association between a panel of single nucleotide polymorphisms (SNPs) in testosterone metabolism genes and POAG. In sex-stratified analyses, we evaluated POAG overall and POAG subtypes defined by maximum IOP (high-tension [HTG] or normal tension glaucoma [NTG]).
Results: In the US dataset, the SNP panel was not associated with POAG (permuted P = 0.77), although there was an association in the Australian sample (permuted P = 0.018). In both datasets, the SNP panel was associated with POAG in men (permuted P ≤ 0.033) and not women (permuted P ≥ 0.42), but in gene-based analyses, there was no consistency on the main genes responsible for these findings. In both datasets, the testosterone pathway association with HTG was significant (permuted P ≤ 0.011), but again, gene-based analyses showed no consistent driver gene associations.
Conclusions: Collectively, testosterone metabolism pathway SNPs were consistently associated with the high-tension subtype of POAG in two datasets
Quantitative evaluation of facet deflection, stiffness, strain and failure load during simulated cervical spine trauma
Get PDF© 2018 Elsevier Ltd. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (March 2018) in accordance with the publisher’s archiving policyTraumatic cervical facet dislocation (CFD) is often associated with devastating spinal cord injury. Facet fractures commonly occur during CFD, yet quantitative measures of facet deflection, strain, stiffness and failure load have not been reported. The aim of this study was to determine the mechanical response of the subaxial cervical facets when loaded in directions thought to be associated with traumatic bilateral CFD – anterior shear and flexion. Thirty-one functional spinal units (6 × C2/3, C3/4, C4/5, and C6/7, 7 × C5/6) were dissected from fourteen human cadaver cervical spines (mean donor age 69 years, range 48–92; eight male). Loading was applied to the inferior facets of the inferior vertebra to simulate the in vivo inter-facet loading experienced during supraphysiologic anterior shear and flexion motion. Specimens were subjected to three cycles of sub-failure loading (10–100 N, 1 mm/s) in each direction, before being failed in a randomly assigned direction (10 mm/s). Facet deflection, surface strains, stiffness, and failure load were measured. Linear mixed-effects models (α = 0.05; random effect of cadaver) accounted for variations in specimen geometry and bone density. Specimen-specific parameters were significantly associated with most outcome measures. Facet stiffness and failure load were significantly greater in the simulated flexion loading direction, and deflection and surface strains were higher in anterior shear at the non-destructive analysis point (47 N applied load). The sub-failure strains and stiffness responses differed between the upper and lower subaxial cervical regions. Failure occurred through the facet tip during anterior shear loading, while failure through the pedicles was most common in flexion
The Experience of Paid Family-Care Workers of People with Dementia in South Korea
Get PDF© 2018 Korean Society of Nursing Science, Published by Elsevier Korea LLC. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Purpose: The South Korean government introduced the universal long-term care insurance program in
2008 that created a new employment category of “paid family-care worker” to assist the elderly with
chronic illnesses including dementia. The aim of this study was to understand the lived experience of
paid family-care workers of people with dementia in South Korea.
Methods: The study was a qualitative research design underpinned by interpretive description principles
involving eight paid family-care workers. The participants were recruited by attaching the advertisement
flyer in a notice board of an educational facility for paid family-care workers.
Results: Paid family-care workers struggled to manage the behavioral and psychological symptoms of
their care recipients. Their workloads created physical, emotional, social, and financial burdens. However,
the care-giving activities were encouraged through their sense of responsibility, filial piety, and personal
religious beliefs. Financial subsidies from the government and help received from others were also
identified as encouragements. The education course provided to them assisted them to improve their
dementia-care capabilities.
Conclusion: Understanding paid family-care workers' lived experience in dementia care in South Korea
assists with the identification of their educational needs and level of support they require to improve
dementia care in the home care environment. A number of suggestions are made to increase paid familycare
workers' knowledge, clinical skills, and job satisfaction to reduce their burdens and work-related
incidents, such as challenging behaviors from those being cared for
Cholinesterase research outreach project (CROP): point of care cholinesterase measurement in an Australian agricultural community
Get PDFThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Abstract
Background
Australian farmers are routinely exposed to a wide variety of agrichemicals, including herbicides and insecticides. Organophosphate (OP) insecticides are widely used for agricultural production, horticulture and animal husbandry practices. Symptoms of OP toxicity are the results of inhibition of the enzyme acetylcholinesterase (AChE) which is found in many types of conducting tissue in human bodies such as nerve and muscle, central and peripheral tissues, motor and sensory fibres. Cholinesterase can be measured in red blood cells/erythrocytes (AChE) and plasma (PChE). This study aims to explore integration of AChE monitoring into routine health checks for those at risk and also to examine any association between AChE activity and agrichemical use in a Victorian farming community in Australia.
Methods
This was a prospective cohort study, where farmers and non-famers were compared on the levels of AChE at four time points of baseline, 3–4 weeks, 6-weeks and at 9-weeks. Study participants (N = 55) were residents from South West Victoria, aged between 18 and 75 years, spoke English, and had not had a previous known acute chemical accident. A total of 41 farming (had been farming for more than 5 years) and a convenience sample of 14 non-farming individuals met the inclusion criteria. Testing of AChE was repeated for all participants with a maximum of three times over 10 weeks.
Results
The integration of AChE monitoring was very well accepted by all participants. There was no significant difference in average AChE activity between farming and non-farming participants (one-way ANOVA p > 0.05) in this study. There was no significant difference between personal use of agricultural chemicals on farm and the levels of AChE at baseline (measurement 1) or any of the follow up periods (p > 0.05). However, the mean activity of AChE was significantly lower within follow up periods [F (2.633, 139.539) = 14.967, p < 0.001]. There was a significant reduction of AChE between the follow up at 3-weeks and 6-weeks period (p = 0.015).
Conclusions
The routine monitoring of AChE may allow for early recognition of chronic low-level exposure to OPs when they are used by farmers, provided a reasonable estimate of baseline AChE is available. This work provides an evidence for recommending the integration of AChE monitoring into point of care (POC) procedures in rural health clinics and quantifying pesticide exposure and personal protection both on the farm and in the home. Farmer engagement is crucial to the successful integration of AChE monitoring into rural health clinics in Australia.
Trial registration
ACTRN12613001256763
Oral Yeast Colonization and Fungal Infections in Peritoneal Dialysis Patients: A Pilot Study
Get PDFCopyright © 2017 Liliana Simões-Silva et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Peritonitis and exit-site infections are important complications in peritoneal dialysis (PD) patients that are occasionally caused by opportunistic fungi inhabiting distant body sites. In this study, the oral yeast colonization of PD patients and the antifungal susceptibility profile of the isolated yeasts were accessed and correlated with fungal infection episodes in the following 4 years. Saliva yeast colonization was accessed in 21 PD patients and 27 healthy controls by growth in CHROMagar-Candida® and 18S rRNA/ITS sequencing. PD patients presented a lower oral yeast prevalence when compared to controls, namely, Candida albicans. Other species were also isolated, Candida glabrata and Candida carpophila. The antifungal susceptibility profiles of these isolates revealed resistance to itraconazole, variable susceptibility to caspofungin, and higher MIC values of posaconazole compared to previous reports. The 4-year longitudinal evaluation of these patients revealed Candida parapsilosis and Candida zeylanoides as PD-related exit-site infectious agents, but no correlation was found with oral yeast colonization. This pilot study suggests that oral yeast colonization may represent a limited risk for fungal infection development in PD patients. Oral yeast isolates presented a variable antifungal susceptibility profile, which may suggest resistance to some second-line drugs, highlighting the importance of antifungal susceptibility assessment in the clinical practice
Differential Telomere Shortening in Blood versus Arteries in an Animal Model of Type 2 Diabetes
Get PDFCopyright © 2015 Samira Tajbakhsh et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Vascular dysfunction is an early feature of diabetic vascular disease, due to increased oxidative stress and reduced nitric oxide (NO) bioavailability. This can lead to endothelial cell senescence and clinical complications such as stroke. Cells can become senescent by shortened telomeres and oxidative stress is known to accelerate telomere attrition. Sirtuin 1 (SIRT1) has been linked to vascular health by upregulating endothelial nitric oxide synthase (eNOS), suppressing oxidative stress, and attenuating telomere shortening. Accelerated leukocyte telomere attrition appears to be a feature of clinical type 2 diabetes (T2D) and therefore the telomere system may be a potential therapeutic target in preventing vascular complications of T2D. However the effect of T2D on vascular telomere length is currently unknown. We hypothesized that T2D gives rise to shortened leukocyte and vascular telomeres alongside reduced vascular SIRT1 expression and increased oxidative stress. Accelerated telomere attrition was observed in circulating leukocytes, but not arteries, in T2D compared to control rats. T2D rats had blunted arterial SIRT1 and eNOS protein expression levels which were associated with reduced antioxidant defense capacity. Our findings suggest that hyperglycemia and a deficit in vascular SIRT1 per se are not sufficient to prematurely shorten vascular telomeres
A rabbit hole between topology and geometry
Get PDFCopyright © 2013 David G. Glynn. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Topology and geometry should be very closely related mathematical subjects dealing with space. However, they deal with different aspects, the first with properties preserved under deformations, and the second with more linear or rigid aspects, properties invariant under translations, rotations, or projections. The present paper shows a way to go between them in an unexpected way that uses graphs on orientable surfaces, which already have widespread applications. In this way infinitely many geometrical properties are found, starting with the most basic such as the bundle and Pappus theorems. An interesting philosophical consequence is that the most general geometry over noncommutative skewfields such as Hamilton's quaternions corresponds to planar graphs, while graphs on surfaces of higher genus are related to geometry over commutative fields such as the real or complex numbers