748 research outputs found

    A semi-analytical solution of micro polar flow in a porous channel with mass injection by using differential transform method

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    In this letter, the differential transform method (DTM) was applied to the micro-polar flow in a porous channel with mass injection. Approximate solutions of the governing system of nonlinear ordinary differential equations were calculated in the form of DTM series with easily computable terms. The validity of the series solutions were verified by comparison with numerical results obtained using a fourth order Runge–Kutta method. The computed DTM velocity profiles are shown and the influence of Reynolds number on the velocity component in x-direction is discussed

    Synthesis of Single-Phase Anatase TiO2 Nanoparticles by Hydrothermal Treatment

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    Pure anatase powders of titanium dioxide with a homogeneous nanosized particles distribution were prepared by a facile hydrothermal route using solution of acetic acid and tetraisopropyl orthotitanate as the precursors with a molar ratio of 1:1. The modified hydrolyzed alkoxide was treated at various temperatures under different autogenic pressures. Two different reactors were employed as autoclaves for heating and generation of high pressures during the synthesis and crystallization of TiO2 nanoparticles. The characteristics of TiO2 powders obtained under various synthesis conditions were verified using X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (FE-SEM). The results indicated that particles size of the formed TiO2 could be finely tuned by varying the experimental parameters of temperature, pressure and the amount of nitric acid in the peptization step. TiO2 nanoparticles with good dispersion and mean size of about 9 nm could be seen in FE-SEM image of sample synthesized under temperature of 160 °C for 12 h using more nitric acid in the peptization step. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3488

    Discrete scale invariance, and its logarithmic extension

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    It is known that discrete scale invariance leads to log-periodic corrections to scaling. We investigate the correlations of a system with discrete scale symmetry, discuss in detail possible extension of this symmetry such as translation and inversion, and find general forms for correlation functions.Comment: 12 pages, LaTe

    Protection against discrimination in national dementia guideline recommendations: A systematic review

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    BACKGROUND: National dementia guidelines provide recommendations about the most effective approaches to diagnosis and interventions. Guidelines can improve care, but some groups such as people with minority characteristics may be disadvantaged if recommended approaches are the same for everyone. It is not known if dementia guidelines address specific needs related to patient characteristics. The objectives of this review are to identify which countries have national guidelines for dementia and synthesise recommendations relating to protected characteristics, as defined in the UK Equality Act 2010: age, disability, gender identity, marriage and civil partnership, pregnancy and maternity, race, religion or belief, sex, and sexual orientation. METHODS AND FINDINGS: We searched CINAHL, PsycINFO, and Medline databases and the Guideline International Network library from inception to March 4, 2020, for dementia guidelines in any language. We also searched, between April and September 2020, Google and the national health websites of all 196 countries in English and in each country’s official languages. To be included, guidelines had to provide recommendations about dementia, which were expected to be followed by healthcare workers and be approved at a national policy level. We rated quality according to the iCAHE guideline quality checklist. We provide a narrative synthesis of recommendations identified for each protected characteristic, prioritising those from higher-quality guidelines. Forty-six guidelines from 44 countries met our criteria, of which 18 were rated as higher quality. Most guidelines (39/46; 85%) made at least one reference to protected characteristics, and we identified recommendations relating to age, disability, race (or culture, ethnicity, or language), religion, sex, and sexual orientation. Age was the most frequently referenced characteristic (31/46; 67%) followed by race (or culture, ethnicity, or language; 25/46; 54%). Recommendations included specialist investigation and support for younger people affected by dementia and consideration of culture when assessing whether someone had dementia and providing person-centred care. Guidelines recommended considering religion when providing person-centred and end-of-life care. For disability, it was recommended that healthcare workers consider intellectual disability and sensory impairment when assessing for dementia. Most recommendations related to sex recommended not using sex hormones to treat cognitive impairment in men and women. One guideline made one recommendation related to sexual orientation. The main limitation of this study is that we only included national guidelines applicable to a whole country meaning guidelines from countries with differing healthcare systems within the country may have been excluded. CONCLUSIONS: National guidelines for dementia vary in their consideration of protected characteristics. We found that around a fifth of the world’s countries have guidelines for dementia. We have identified areas of good practice that can be considered for future guidelines and suggest that all guidelines provide specific evidence-based recommendations for minority groups with examples of how to implement them. This will promote equity in the care of people affected by dementia and help to ensure that people with protected characteristics also have high-quality clinical services

    Emergence and patterning dynamics of mouse-definitive endoderm

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    The segregation of definitive endoderm (DE) from bipotent mesendoderm progenitors leads to the formation of two distinct germ layers. Dissecting DE commitment and onset has been challenging as it occurs within a narrow spatiotemporal window in the embryo. Here, we employ a dual Bra/Sox17 reporter cell line to study DE onset dynamics. We find Sox17 expression initiates in vivo in isolated cells within a temporally restricted window. In 2D and 3D in vitro models, DE cells emerge from mesendoderm progenitors at a temporally regular, but spatially stochastic pattern, which is subsequently arranged by self-sorting of Sox17 + cells. A subpopulation of Bra-high cells commits to a Sox17+ fate independent of external Wnt signal. Self-sorting coincides with upregulation of E-cadherin but is not necessary for DE differentiation or proliferation. Our in vivo and in vitro results highlight basic rules governing DE onset and patterning through the commonalities and differences between these systems

    Height Fluctuations and Intermittency of V2O5V_2 O_5 Films by Atomic Force Microscopy

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    The spatial scaling law and intermittency of the V2O5V_2 O_5 surface roughness by atomic force microscopy has been investigated. The intermittency of the height fluctuations has been checked by two different methods, first, by measuring scaling exponent of q-th moment of height-difference fluctuations i.e. Cq=C_q = and the second, by defining generating function Z(q,N)Z(q,N) and generalized multi-fractal dimension DqD_q. These methods predict that there is no intermittency in the height fluctuations. The observed roughness and dynamical exponents can be explained by the numerical simulation on the basis of forced Kuramoto-Sivashinsky equation.Comment: 6 pages (two columns), 11 eps. figures, late

    PTH(1–34) treatment and/or mechanical loading have different osteogenic effects on the trabecular and cortical bone in the ovariectomized C57BL/6 mouse

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    In preclinical mouse models, a synergistic anabolic response to PTH(1–34) and tibia loading was shown. Whether combined treatment improves bone properties with oestrogen deficiency, a cardinal feature of osteoporosis, remains unknown. This study quantified the individual and combined longitudinal effects of PTH(1–34) and loading on the bone morphometric and densitometric properties in ovariectomised mice. C57BL/6 mice were ovariectomised at 14-weeks-old and treated either with injections of PTH(1–34); compressive loading of the right tibia; both interventions concurrently; or both interventions on alternating weeks. Right tibiae were microCT-scanned from 14 until 24-weeks-old. Trabecular metaphyseal and cortical midshaft morphometric properties, and bone mineral content (BMC) in 40 different regions of the tibia were measured. Mice treated only with loading showed the highest trabecular bone volume fraction at week 22. Cortical thickness was higher with co-treatment than in the mice treated with PTH alone. In the mid-diaphysis, increases in BMC were significantly higher with loading than PTH. In ovariectomised mice, the osteogenic benefits of co-treatment on the trabecular bone were lower than loading alone. However, combined interventions had increased, albeit regionally-dependent, benefits to cortical bone. Increased benefits were largest in the mid-diaphysis and postero-laterally, regions subjected to higher strains under compressive loads

    Structure-Sensitive Mechanism of Nanographene Failure

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    The response of a nanographene sheet to external stresses is considered in terms of a mechanochemical reaction. The quantum chemical realization of the approach is based on a coordinate-of-reaction concept for the purpose of introducing a mechanochemical internal coordinate (MIC) that specifies a deformational mode. The related force of response is calculated as the energy gradient along the MIC, while the atomic configuration is optimized over all of the other coordinates under the MIC constant-pitch elongation. The approach is applied to the benzene molecule and (5, 5) nanographene. A drastic anisotropy in the microscopic behavior of both objects under elongation along a MIC has been observed when the MIC is oriented either along or normally to the C-C bonds chain. Both the anisotropy and high stiffness of the nanographene originate at the response of the benzenoid unit to stress.Comment: 19 pages, 7 figures 1 tabl

    A Survey on Continuous Time Computations

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    We provide an overview of theories of continuous time computation. These theories allow us to understand both the hardness of questions related to continuous time dynamical systems and the computational power of continuous time analog models. We survey the existing models, summarizing results, and point to relevant references in the literature
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