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1.
《Health & place》2022
IntroductionWe extend previous research to illustrate how individual, interpersonal and neighbourhood factors in a high-density urban setting in Vancouver, Canada, shape social connectedness experiences of community-dwelling older adults during the first wave of the COVID-19 pandemic.MethodsWe conducted 31 semi-structured interviews and collected objective measures of loneliness and social connectedness (surveys).ResultsThree dimensions of the neighbourhood environment influenced social connectedness: (i) interactions with neighbours, (ii) involvement with neighbourhood-based organizations, and (ii) outdoor pedestrian spaces. Seventy-one percent of participants felt a strong sense of belonging to their local community, while 39% were classified as high or extremely lonely.SummaryMany participants leveraged pre-existing social ties to maintain connections during the pandemic. However, volunteer outreach was vital for more isolated older adults. Although many participants felt lonely and isolated at times, the relative ease and accessibility with which they could connect with others in their neighbourhood environment, may have helped mitigate persistent loneliness.ConclusionStrategies that foster social connectedness over the longer term, need to prioritize the needs of older adults who face multiple barriers to equitable social participation. 相似文献
2.
High-Order Positivity-Preserving Well-Balanced Discontinuous Galerkin Methods for Euler Equations with Gravitation on Unstructured Meshes 下载免费PDF全文
Weijie Zhang Yulong Xing Yinhua Xia & Yan Xu 《Communications In Computational Physics》2022,31(3):771-815
In this paper, we propose a high-order accurate discontinuous Galerkin
(DG) method for the compressible Euler equations under gravitational fields on unstructured meshes. The scheme preserves a general hydrostatic equilibrium state and
provably guarantees the positivity of density and pressure at the same time. Comparing with the work on the well-balanced scheme for Euler equations with gravitation
on rectangular meshes, the extension to triangular meshes is conceptually plausible
but highly nontrivial. We first introduce a special way to recover the equilibrium state
and then design a group of novel variables at the interface of two adjacent cells, which
plays an important role in the well-balanced and positivity-preserving properties. One
main challenge is that the well-balanced schemes may not have the weak positivity
property. In order to achieve the well-balanced and positivity-preserving properties
simultaneously while maintaining high-order accuracy, we carefully design DG spatial discretization with well-balanced numerical fluxes and suitable source term approximation. For the ideal gas, we prove that the resulting well-balanced scheme, coupled with strong stability preserving time discretizations, satisfies a weak positivity
property. A simple existing limiter can be applied to enforce the positivity-preserving
property, without losing high-order accuracy and conservation. Extensive one- and
two-dimensional numerical examples demonstrate the desired properties of the proposed scheme, as well as its high resolution and robustness. 相似文献
3.
《Research in social & administrative pharmacy》2022,18(2):2345-2349
This commentary looks at the process of conducting a systematic review of surveys and validated questionnaires. Surveys and other questionnaire style tools are often used in the field of social and administrative pharmacy, to capture beliefs, attitudes and experiences of patients and healthcare professionals (including pharmacists). Currently, there is little guidance available on how to conduct a systematic review of these types of studies. Considerations related to the process of a systematic review are highlighted, including identification of articles, data extraction, assessing quality of articles and synthesis and analysis of data. 相似文献
4.
《Health & place》2022
Low-income communities and communities of color face multiple, cumulative environmental and social burdens. Methods development in environmental justice research has largely focused on spatial and quantitative approaches. Less attention has been paid to developing methodologies that help collect information on everyday stressors and quality of life experiences for residents in overburdened communities. Mixed methods approaches can be one way to structure study designs that help consider how residents experience environmental and socioeconomic impacts in a localized community context. In neighborhoods burdened by cumulative stressors, traditional cross-sectional epidemiological research designs can also be challenging, as well as limited or narrow in their application. However, repeat sampling of measures within a vulnerable population can approach a quasi-experimental design and help consider variations within residents in a single neighborhood as well as better parse relationships between exposures and outcomes. Through a community-academic partnership with university partners, local community partners, and a local promotores de salud (community health workers) network, we pilot tested a novel mobile daily diary approach in both English and Spanish in an urban, predominantly immigrant community in South Los Angeles as a potential method to collect information on daily stress, environmental quality, and health status/symptoms. We collected resident responses via a once per day 7-day SMS/text messaging survey. We sought to gather granular data on daily resident experiences of air pollution and environmental hazards. Residents reported acute health symptoms and stressors, with repeat measures demonstrating how residents might rank, categorize, or cope with stressors. We find that residents in environmental justice communities record variation in their daily diary responses and document changes in environmental quality, stressors, and odors. Refining this type of method could enable a more rigorous examination of co-occurrences of environmental quality and acute health symptoms. This approach supports the inclusion of residents in the research process and helps more systematically integrate open-ended environmental health relevant data in environmental justice efforts. Used with measured data such as air monitoring or health measures, mixed methods generated data can help support efforts that aim to alleviate sources of daily stress, alongside efforts to reduce overall pollution burdens. Mobile daily diaries can be one way to capture variable responses to environmental quality, acute health symptoms, and stressors. 相似文献
5.
《Journal of the American College of Radiology》2022,19(7):854-865
ObjectiveThe purpose of this study was to update trends, investigate sociodemographic disparities, and evaluate the impact on mortality of stroke neuroimaging across the United States from 2012 to 2019.MethodsRetrospective cohort study using CMS Medicare 5% Research Identifiable Files, representing consecutive ischemic stroke emergency department or hospitalized patients aged ≥65 years. A total of 85,547 stroke episodes with demographic and clinical information were analyzed using Cochran-Mantel-Haenszel tests and logistic regression. Outcome measures were neuroimaging (CT angiography [CTA], CT perfusion [CTP], MRI, MR angiography [MRA]) utilization, acute treatment (endovascular thrombectomy [EVT] and intravenous thrombolysis [IVT]), and mortality while in the hospital and at 30 days and 1 year post discharge.ResultsSignificantly increasing utilization trends for CTA (250%), CTP (428%) and MRI (18%), and a decreasing trend for MRA (?33%) were observed from 2012 to 2019 (P < .0001). Controlling for covariates in the logistic regression models, CTA and CTP were significantly associated with higher EVT and IVT utilization. Although CTA, MRI, and MRA were associated with lower mortality, CTP was associated with higher mortality post discharge. Less neuroimaging was performed in rural patients; older patients (≥80 years) had lower utilization of CTA, MRI, and MRA; female patients had lower rates of CTA; and Black patients had lower utilization of CTA and CTP.ConclusionsCTA and CTP utilization increased in the Medicare ischemic stroke population from 2012 to 2019 and both were associated with greater EVT and IVT use. However, disparities exist in neuroimaging utilization across all demographic groups, and further understanding of the root causes of these disparities will be crucial to achieving equity in stroke care. 相似文献
6.
7.
Pauline A. J. Mendelaar Jaco Kraan Mai Van Leonie L. Zeune Leon W. M. M. Terstappen Esther Oomende Hoop John W. M. Martens Stefan Sleijfer 《Molecular oncology》2021,15(1):116
Circulating tumor cells (CTCs) in the blood of cancer patients are of high clinical relevance. Since detection and isolation of CTCs often rely on cell dimensions, knowledge of their size is key. We analyzed the median CTC size in a large cohort of breast (BC), prostate (PC), colorectal (CRC), and bladder (BLC) cancer patients. Images of patient‐derived CTCs acquired on cartridges of the FDA‐cleared CellSearch® method were retrospectively collected and automatically re‐analyzed using the accept software package. The median CTC diameter (μm) was computed per tumor type. The size differences between the different tumor types and references (tumor cell lines and leukocytes) were nonparametrically tested. A total of 1962 CellSearch® cartridges containing 71 612 CTCs were included. In BC, the median computed diameter (CD) of patient‐derived CTCs was 12.4 μm vs 18.4 μm for cultured cell line cells. For PC, CDs were 10.3 μm for CTCs vs 20.7 μm for cultured cell line cells. CDs for CTCs of CRC and BLC were 7.5 μm and 8.6 μm, respectively. Finally, leukocytes were 9.4 μm. CTC size differed statistically significantly between the four tumor types and between CTCs and the reference data. CTC size differences between tumor types are striking and CTCs are smaller than cell line tumor cells, whose size is often used as reference when developing CTC analysis methods. Based on our data, we suggest that the size of CTCs matters and should be kept in mind when designing and optimizing size‐based isolation methods.
Abbreviations
- ACCEPT
- Automated CTC Classification, Enumeration, and PhenoTyping software
- BC
- breast cancer
- BLC
- bladder cancer
- CD
- computed diameter
- CEL
- cultured tumor cell (cell line)
- CK
- cytokeratin
- CRC
- colorectal cancer
- CTC‐L
- circulating tumor cells derived from cerebrospinal fluid (liquor)
- CTCs
- circulating tumor cells
- DAPI
- 4′6‐diamidino‐2‐phenylindole
- EMT
- epithelial–mesenchymal transition
- EpCAM
- epithelial cell adhesion molecule
- IQR
- interquartile range
- KW test
- Kruskal–Wallis test
- MWU test
- Mann–Whitney U test
- NCR
- nucleus/cytoplasm ratio
- P2A
- perimeter to area
- PC
- prostate cancer
- TIF
- tagged Image Format files
- TXT
- text file
- μm
- micrometer
- µm2
- square micrometers
8.
《Journal of the American College of Radiology》2021,18(6):820-833
PurposeNational guidelines recommend prompt identification of candidates for acute ischemic stroke (AIS) treatment, requiring timely neuroimaging with CT and/or MRI. CT is often preferred because of its widespread availability and rapid acquisition. Despite higher diagnostic accuracy of MRI, it commonly involves complex workflows that could potentially cause treatment time delays. The purpose of this study was to analyze the impact on outcomes of imaging utilization before treatment decisions at comprehensive stroke centers for patients presenting with suspected AIS in the anterior circulation with last-known-well-to-arrival time 0 to 24 hours.MethodsA decision simulation model based on the American Heart Association’s recommendations for AIS care pathways was developed from a health care perspective to compare initial imaging strategies: (1) stepwise-CT: noncontrast CT (NCCT) at the time of presentation, with CT angiography (CTA) ± CT perfusion (CTP) only in select patients (initial imaging to exclude hemorrhage and extensive ischemia) for mechanical thrombectomy (MT) evaluation; (2) stepwise-hybrid: NCCT at the time of presentation, with MR angiography (MRA) ± MR perfusion (MRP) only for MT evaluation; (3) stepwise-advanced: NCCT + CTA at presentation, with MR diffusion-weighted imaging (MR DWI) + MRP only for MT evaluation; (4) comprehensive-CT: NCCT + CTA + CTP at the time of presentation; and (5) comprehensive-MR: MR DWI + MRA + MRP at the time of presentation. Model parameters were defined using evidence-based data. Cost-effectiveness and sensitivity analyses were performed.ResultsThe cost-effectiveness analyses revealed that comprehensive-CT and comprehensive-MR yield the highest lifetime quality-adjusted life-years (QALYs) (4.81 and 4.82, respectively). However, the incremental cost-effectiveness ratio of comprehensive-MR is $233,000/QALY compared with comprehensive-CT. Stepwise-CT, stepwise-hybrid, and stepwise-advanced strategies are dominated, yielding lower QALYs and higher costs compared with comprehensive-CT.ConclusionsPerforming comprehensive-CT at presentation is the most cost-effective initial imaging strategy at comprehensive stroke centers. 相似文献
9.
10.
目的探讨不同手术方法治疗复杂胫骨平台骨折临床疗效。方法选择2016年1月—2018年12月84例复杂胫骨平台骨折患者,随机分组。单侧锁定钢板内固定组选择单侧锁定钢板内固定手术,双侧切口双侧解剖钢板内固定组选择双侧切口双侧解剖钢板内固定。分析手术操作时间、手术失血、平均住院天数以及复杂胫骨平台骨折愈合时间;治疗前后患者视觉模拟评分和Rasmussen膝关节功能评分;膝关节僵硬发生率。结果双侧切口双侧解剖钢板内固定组视觉模拟评分和Rasmussen膝关节功能评分、手术操作时间、手术失血、平均住院天数以及复杂胫骨平台骨折愈合时间、膝关节僵硬发生率和单侧锁定钢板内固定组比较有优势,P<0.05。结论复杂胫骨平台骨折患者实施双侧切口双侧解剖钢板内固定可获得较好效果。 相似文献