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Guo-Quan Shi Huajun Zhu & Zhen-Guo Yan 《Communications In Computational Physics》2022,31(4):1215-1241
A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on
modal energy coefficients is proposed to detect troubled cells, where discontinuities
exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme
based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR
method. Numerical investigations show that the proposed subcell limiting strategy on
unstructured quadrilateral meshes is robust in shock-capturing. 相似文献
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吕建裕 《中国医疗器械信息》2022,(4)
输尿管上段结石为临床中常见泌尿系结石类型之一,如不能及时诊治,可引起重度积水、泌尿系感染,甚至脓毒血症,对患者肾功能、健康造成严重影响。随着微创治疗技术在泌尿系结石中应用,微创治疗方法能降低对患者造成治疗性创伤,降低相关并发症发生率,促进患者康复,了解临床中微创治疗输尿管上段结石方法,对临床中合理治疗输尿管上段结石有重要价值。 相似文献
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《The Journal for Nurse Practitioners》2022,18(4):372-376
The effects of climate change include floods, hurricanes, heat waves, and fires; these natural disasters can result in respiratory, cardiovascular, and psychological harm in older adults, who experience the highest morbidity and mortality during heat waves. Advanced practice registered nurses (APRNs) need education on preparing, assessing, and treating older adults for climate-change disasters, especially heat waves. This article will help APRNs understand the effects of climate-change events on the vulnerable older adults and advocates for the need to integrate health effects of climate change into curricula, practicums, policy, and research agendas. 相似文献
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This meta-analysis was designed to assess the effectiveness and safety of extracorporeal shock wave therapy (ESWT) for patients with low back pain (LBP). Pubmed, Embase, Cochrane's library, PEDro (Physiotherapy Evidence Database), China National Knowledge Infrastructure (CNKI), and Wanfang Data were searched until December 2019 to identify studies assessing the effectiveness and safety of EPSW for LBP. The prime outcome is pain intensity measured by Visual Analog Scale (VAS) or numeric rating scale (NRS). Other outcomes included functional status, quality of life, psychological outcomes measured by Oswestry Disability Index (ODI), as well as the adverse events. Mean differences (MD) were calculated for continuous outcomes, while odd ratios (OR) were calculated for binary outcomes. Revman 5.3 software was used for statistical analysis. Five randomized controlled trials (RCTs) were finally included in this meta-analysis. The pooled mean difference in post-treatment pain scores was −2.37 (P <0.0001), indicating that post-treatment pain scores was significantly higher by 2.37 in control group than in ESWT group. At a mean follow-up time of 4–6 weeks, the pooled mean difference in ODI scores was −14.10 (P <0.00001), indicating that the pooled mean difference of post-treatment ODI scores was 14.10 higher in control group than in ESWT group. The use of ESWT is effective in alleviating pain and improving the general functional state for patients with LBP. However, more evidence was needed to verify its safety. 相似文献
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目的探讨血清同型半胱氨酸(Hcy)、胰岛素样生长因子结合蛋白-1(IGFBP-1)联合检测对多囊卵巢综合征患者孕早期自然流产的预测价值。方法选取2018年3月—2020年5月行促排卵治疗并成功临床妊娠的多囊卵巢综合征165例,检测血清Hcy、IGFBP-1水平。根据孕早期自然流产发生情况分为孕早期自然流产组与未自然流产组,比较两组妊娠前一次促排卵后血清Hcy、IGFBP-1水平;多囊卵巢综合征患者孕早期自然流产的危险因素采用多因素Logistic回归分析,并采用受试者工作特征(ROC)曲线分析血清Hcy、IGFBP-1水平单项及联合检测对多囊卵巢综合征患者孕早期自然流产的预测价值。结果患者妊娠前一次促排卵后血清Hcy水平低于入院时,血清IGFBP-1水平高于入院时(P<0.01);自然流产组妊娠前一次促排卵后血清Hcy水平高于未自然流产组,血清IGFBP-1水平低于未自然流产组(P<0.01)。孕早期自然流产的发生率为28.48%。年龄≥35岁、多囊卵巢综合征分型、空腹胰岛素水平偏高、空腹血糖水平偏高、血清睾酮水平偏高、血清叶酸水平偏低、妊娠前一次促排卵后血清Hcy水平偏高及血清IGFBP-1水平偏低均是多囊卵巢综合征患者孕早期自然流产的危险因素(P<0.01)。妊娠前一次促排卵后血清Hcy水平联合血清IGFBP-1水平预测多囊卵巢综合征患者孕早期自然流产的敏感度、ROC曲线下面积均高于单独预测(P<0.01)。结论多囊卵巢综合征孕早期自然流产患者血清Hcy水平偏高,IGFBP-1水平偏低,二者均与多囊卵巢综合征患者孕早期自然流产密切相关,并对多囊卵巢综合征患者孕早期自然流产的发生具有较好的预测价值,联合检测时的预测效能更高。 相似文献
8.
《Clinical neurophysiology》2021,132(9):2003-2011
ObjectiveA large N20 and P25 of the median nerve somatosensory evoked potential (SEP) predicts short survival in amyotrophic lateral sclerosis (ALS). We investigated whether high frequency oscillations (HFOs) over N20 are enlarged and associated with survival in ALS.MethodsA total of 145 patients with ALS and 57 healthy subjects were studied. We recorded the median nerve SEP and measured the onset-to-peak amplitude of N20 (N20o-p), and peak-to-peak amplitude between N20 and P25 (N20p-P25p). We obtained early and late HFO potentials by filtering SEP between 500 and 1 kHz, and measured the peak-to-peak amplitude. We followed up patients until endpoints (death or tracheostomy) and analyzed the relationship between SEP or HFO amplitudes and survival using a Cox analysis.ResultsPatients showed larger N20o-p, N20p-P25p, and early and late HFO amplitudes than the control values. N20p-P25p was associated with survival periods (p = 0.0004), while early and late HFO amplitudes showed no significant association with survival (p = 0.4307, and p = 0.6858, respectively).ConclusionsThe HFO amplitude in ALS is increased, but does not predict survival.SignificanceThe enlarged HFOs in ALS might be a compensatory phenomenon to the hyperexcitability of the sensory cortex pyramidal neurons. 相似文献
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