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1.
In this paper, a high-order moment-based multi-resolution Hermite
weighted essentially non-oscillatory (HWENO) scheme is designed for hyperbolic conservation laws. The main idea of this scheme is derived from our previous work [J.
Comput. Phys., 446 (2021) 110653], in which the integral averages of the function and
its first order derivative are used to reconstruct both the function and its first order
derivative values at the boundaries. However, in this paper, only the function values at
the Gauss-Lobatto points in the one or two dimensional case need to be reconstructed
by using the information of the zeroth and first order moments. In addition, an extra
modification procedure is used to modify those first order moments in the troubled-cells, which leads to an improvement of stability and an enhancement of resolution
near discontinuities. To obtain the same order of accuracy, the size of the stencil required by this moment-based multi-resolution HWENO scheme is still the same as the
general HWENO scheme and is more compact than the general WENO scheme. Moreover, the linear weights are not unique and are independent of the node position, and
the CFL number can still be 0.6 whether for the one or two dimensional case, which has
to be 0.2 in the two dimensional case for other HWENO schemes. Extensive numerical
examples are given to demonstrate the stability and resolution of such moment-based
multi-resolution HWENO scheme. 相似文献
2.
《Journal of the American Medical Directors Association》2020,21(8):1093-1101.e1
ObjectivesDementia is a progressive incurable life-limiting illness. Previous research suggests end-of-life care for people with dementia should have a symptomatic focus with an effort to avoid burdensome interventions that would not improve quality of life. This study aims to assess the appropriateness of end-of-life care in people who died with dementia in Belgium and to establish relative performance standards by measuring validated population-level quality indicators.DesignWe conducted a retrospective observational study.Setting and ParticipantsWe included all persons deceased with dementia in 2015 in Belgium. Data from 8 administratively collected population-level databases was linked.MeasuresWe used a validated set of 28 quality indicators for end-of-life dementia care. We compared quality indicator scores across 14 healthcare regions to establish relative benchmarks.ResultsIn Belgium in 2015, 10,629 people died with dementia. For indicators of appropriate end-of-life care, people who died with dementia had on average 1.83 contacts with their family physician in the last week before death, whereas 68.4% died at home or in their nursing home of residence. For indicators of inappropriate end-of-life care, 32.4% were admitted to the hospital and 36.3% underwent diagnostic testing in the last 30 days before death, whereas 25.1% died in the hospital. In the last 30 days, emergency department admission varied between 19% and 31%, dispensing of gastric protectors between 18% and 42%, and antihypertensives between 40% and 53% between healthcare regions, with at least 25% of health regions below 46%.Conclusions and ImplicationsOur study found indications of appropriate as well as inappropriate end-of-life care in people with dementia, including high rates of family physician contact, as well as high percentages of diagnostic testing, and emergency department and hospital admissions. We also found high risk-adjusted variation for multiple quality indicators, indicating opportunity for quality improvement in end-of-life dementia care. 相似文献
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《Actas urologicas espa?olas》2022,46(9):550-556
ObjectiveProstate cancer (PCa) is the second most common solid tumor in men and the fifth leading cause of cancer-related death. In advanced stage, palliative treatments are used instead of curative therapies. Therefore, finding predictive indicators seems crucial. Patients with castration-resistant prostate cancer (CRPC) that received Dx chemotherapy have been retrospectively reviewed. The aim of this study was to investigate whether docetaxel (Dx)-free interval could have a predictive value for PCa and influence other sequential therapies.Material and methodsThis clinical trial study was performed on 104 patients at Medeniyet University Oncology Clinic in 2018-2020. All CRPC patients had metastases, received Dx as first-line treatment and underwent androgen receptor axis targeted (ARAT) therapy after disease progression. We analyzed patients’ progression time after Dx therapy and the effects on sequential treatment.ResultsAfter Dx therapy, all patients received ARAT (abiraterone (ABI) n: 49 (47.1%) and enzalutamide (ENZ) n: 54 (51.9%)) as a second-line treatment, except for one patient who received cabazitaxel. There was a statistically significant relationship between the Dx-free interval and duration of response to ARAT (P<.001). The response time of ARAT treatment was <10.5 months in all patients whose Dx-free interval period was <9 months.ConclusionsOur findings support the theory that Dx-free interval can be a predictive factor for CRPC. CRPC disease can be classified as Dx-sensitive disease or Dx-resistance disease, based on the Dx-free interval. Decision on subsequent treatments could be made considering this information. 相似文献
6.
In this paper, we introduce a new type of troubled-cell indicator to improve
hybrid weighted essentially non-oscillatory (WENO) schemes for solving the hyperbolic conservation laws. The hybrid WENO schemes selectively adopt the high-order
linear upwind scheme or the WENO scheme to avoid the local characteristic decompositions and calculations of the nonlinear weights in smooth regions. Therefore,
they can reduce computational cost while maintaining non-oscillatory properties in
non-smooth regions. Reliable troubled-cell indicators are essential for efficient hybrid
WENO methods. Most of troubled-cell indicators require proper parameters to detect
discontinuities precisely, but it is very difficult to determine the parameters automatically. We develop a new troubled-cell indicator derived from the mean value theorem
that does not require any variable parameters. Additionally, we investigate the characteristics of indicator variable; one of the conserved properties or the entropy is considered as indicator variable. Detailed numerical tests for 1D and 2D Euler equations are
conducted to demonstrate the performance of the proposed indicator. The results with
the proposed troubled-cell indicator are in good agreement with pure WENO schemes.
Also the new indicator has advantages in the computational cost compared with the
other indicators. 相似文献
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8.
目的建立三级医院延续性护理服务质量评价指标体系,为客观评价与规范三级医院延续性护理服务提供参考。方法以"结构-过程-结果"模式为基础,结合现行延续性护理服务内容和患者需求,参考国内外文献和专家访谈形成问卷初稿;采用德尔菲(Delphi)法,通过2轮23名专家咨询初步确立三级医院延续性护理服务质量评价指标体系。结果专家咨询的权威系数、判断系数、熟悉系数分别为0.882,0.942,0.822;确定三级医院延续性护理服务质量评价指标体系,包括一级指标3项,二级指标10项,三级指标41项;一、二、三级指标的协调系数分别为0.736、0.521、0.627,具有统计学意义(均P0.01)。结论三级医院延续性护理服务质量评价指标体系内容科学可靠,有助于客观评价延续性护理服务质量,促进护理质量提升。 相似文献
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10.
牙龈色板对比色板色标颜色的影响 总被引:5,自引:0,他引:5
目的 通过定量分析比色板色标在附有牙龈色板时色度三属性的变化,分析并预测牙龈色板对视觉比色将产生何种影响。方法 首先选用2组配有牙龈色板的新比色板(Vintage Halo),在统一条件下分别对所有色标进行测色,以CIE L^*a^*b^*系统记录,转换为CIE L^*C^*H^*值。然后将色标分别安装3种牙龈色板(GumL、GumM、GumD)重复以上过程。计算并分析使用牙龈色板前后的色差以及色度三属性的变化情况。结果 统计检验各色标在无牙龈色板、浅色牙龈色板、中色牙龈色板以及深色牙龈色板情况下的测色结果,分析表明安装牙龈色板各实验组色标与空白对照组相比L^*、C^*ab值无明显改变,但是H^0ab值明显下降,变化范围:GumL组(0.52~4.49),平均下降2.12;GumM组(0.90~4.80),平均下降2.46;GumD组(0.66~4.41),平均下降2.01。色差变化范围:GumL组(0、77-3.16),平均1.804;GumM组(0.75~3.43),平均1.676;GumD组(0.61~3.68)。平均1.652,但使用不同浓淡颜色牙龈色板的3组间无明显差异。结论 使用牙龈色板时色标颜色出现了较明显改变,色差值达到1.6~1.8,视觉感觉色差很明显,可以影响临床比色结果。 相似文献