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1.
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
2.
3.
Baclofen (fun drug) and ethanol combined poisoning in humans: A histopathology and morphometry model
Background– This study intends to address the scarcity of data regarding the pathogenesis of Baclofen poisoning in humans, which has seen a recent increase, worldwide, especially amongst the young people. Another reason for the conduction of this study was lack of the substantial data about the histo-pathological findings of lungs, in synergistic toxicity of Baclofen with Ethanol, in-spite of it being very common in humans, and both being respiratory depressant with similar mechanism of action.Purpose– The authors aimed to understand the pathogenesis of fatal poisonings in humans due to Baclofen in combination with Ethanol via an animal research model. The enhancement of the overall scientific literature by extending research along the lines of the handful studies available in this regard was another adjunct goal of the study.Material and methodsFifteen Wistar rats were divided into control and test group of five and ten subjects respectively. The test group was further divided into two sub-groups of five each, with Baclofen administered to one, and it in conjunction with Ethanol to the other, in lowest dosages adjusted for the humans. Rats in both the groups were euthanized by dislocation of the cervical vertebrae for the histopathology examination.ResultsCapillary and venous plethora, hemorrhages in the inter-alveolar septi, hemorrhages into the alveoli and sludging was seen in the 1st sub-group. The plethora of venules, capillaries and arterioles, with sludging by the WBC (white blood corpuscle) infiltrates was seen in the 2nd sub-group. Desquamation of the ciliated epithelium and edematous thickening of the intra-alveolar septi, along with features suggestive of the peri-vascular edema was seen in the 2nd sub-group. The morphometric analysis of the micro vessels showed a significantly higher value of the arteriolar diameter in the 2nd sub-group, in comparison to 1st, but the venular diameter in the two sub-groups did not differ to any extent. 相似文献
4.
目的 探讨青岛市≥40岁吸烟人群中慢性阻塞性肺疾病(COPD)患病现状,并分析COPD发病相关影响因素。方法 2021年8—12月采用多阶段分层整群随机抽样方法抽取有吸烟习惯居民的家庭户中年龄≥40岁的吸烟者作为调查对象开展问卷调查、体格检查以及肺功能检查,分析吸烟人群中COPD患病现状,并对COPD发生相关影响因素开展研究。结果 共纳入吸烟者1 516人,男性占81.06%,吸烟包年≥21者占70.25%,吸烟年数≥31年者占71.17%;发生COPD 297例,发生率为19.59%。多因素Logistic分析结果显示,男性(OR=3.706)、50~59岁(OR=1.567)、60~69岁(OR=2.585)、≥70岁(OR=4.926)、城镇居民(OR=1.568)、BMI<18.5(OR=3.848)、被动吸烟(OR=2.516)、吸烟包年11~20(OR=1.903)、吸烟包年21~30(OR=2.472)、吸烟包年≥31(OR=3.792)、吸烟年数31~40(OR=2.400)、吸烟年数≥41(OR=4.227)为吸烟人群COPD发生的危险因素。趋势χ2分析显示:随着吸烟包年、吸烟年数不断增加,吸烟者COPD发生率逐渐升高(均P<0.01)。Spearman相关分析显示:COPD病情程度与吸烟包年、吸烟年数呈显著正相关,COPD病情程度会随着吸烟包年、吸烟年数增加而不断加深(均P<0.01)。结论 青岛市≥40岁吸烟人群以男性为主,COPD发生率较高。男性、高龄、城镇居民、低BMI、被动吸烟为吸烟者COPD发生的危险因素,吸烟包年与吸烟年数越高可增加COPD发生风险。 相似文献
5.
目的观察吸气肌训练(IMT)对病态肥胖患者减肥术后肺功能、呼吸肌力量及耐力的影响。方法采用随机数字表法将36例拟行减肥手术的病态肥胖患者分为观察组及对照组, 每组18例。观察组及对照组患者均于术后第2~30天期间进行IMT训练, 吸气阻力值分别设定为最大吸气压(MIP)的40%和5%水平, 每天训练20 min。于手术前及术后第2, 7, 14, 30天时分别检测对比2组患者肺功能[包括用力肺活量(FVC)、1 s用力呼气容积(FEV1)及最大呼气流速(PEF)等]、呼吸肌力量[包括最大吸气压(MIP)和最大呼气压(MEP)]及耐力情况。结果观察组各项肺功能指标[FVC:(91.6±11.2)% vs (105.5±10.8)%, P>0.05;FEV1:(92.1±15.6)% vs (104.7±11.3)%, P>0.05;PEF:(91.1±10.5)% vs (103.5±14.3)%, P>0.05]在术后第7天时均恢复至手术前水平, 对照组各项肺功能指标[FVC:(95.8±11.2)% vs (104.5±10.5)%, P>0.05;FEV1:... 相似文献
6.
目的 对手卫生行为量表(Hand Hygiene Behaviour Questionnaire,HHBQ)进行汉化,并检验其信效度。方法 根据跨文化调试指南,对HHBQ进行前译、前译综合、回译、回译综合、原作者审核、专家咨询、预测试,形成中文版HHBQ。2021年7月—10月对杭州市3所三级甲等医院的537名医务人员进行调查,评价中文版HHBQ的信效度。 结果 中文版HHBQ包含3个维度,分别是手卫生能力(5个条目)、手卫生机会(7个条目)、手卫生动机(5个条目)。总量表内容效度指数为0.995,量表各条目内容效度指数为0.923~1.000。探索性因子分析共提取3个公因子,累计方差贡献率为68.741%。验证性因子分析显示模型拟合度良好。总量表的Cronbach’s α系数为0.918,各维度的Cronbach’s α系数为0.871~0.906。量表的重测信度为0.739。 结论 中文版HHBQ具有良好的信效度,可全面评估医务人员手卫生的影响因素。 相似文献
7.
Kinetic Slip Boundary Condition for Isothermal Rarefied Gas Flows Through Static Non-Planar Geometries Based on the Regularized Lattice-Boltzmann Method 下载免费PDF全文
Jean-Michel Tucny David Vidal Sé bastien Leclaire & Franç ois Bertrand 《Communications In Computational Physics》2022,31(3):816-868
The simulation of rarefied gas flows through complex porous media is challenging due to the tortuous flow pathways inherent to such structures. The Lattice
Boltzmann method (LBM) has been identified as a promising avenue to solve flows
through complex geometries due to the simplicity of its scheme and its high parallel
computational efficiency. It has been proposed to model the stress-strain relationship
with the extended Navier-Stokes equations rather than attempting to directly solve
the Boltzmann equation. However, a regularization technique is required to filter out
non-resolved higher-order components with a low-order velocity scheme. Although
slip boundary conditions (BCs) have been proposed for the non-regularized multiple
relaxation time LBM (MRT-LBM) for planar geometries, previous slip BCs have never
been verified extensively with the regularization technique. In this work, following
an extensive literature review on the imposition of slip BCs for rarefied flows with the
LBM, it is proven that earlier values for kinetic parameters developed to impose slip
BCs are inaccurate for the regularized MRT-LBM and differ between the D2Q9 and
D3Q15 schemes. The error was eliminated for planar flows and good agreement between analytical solutions for arrays of cylinders and spheres was found with a wide
range of Knudsen numbers. 相似文献
8.
目的研究全自动胎儿肺部超声分析与晚期早产儿呼吸系统疾病的相关性。方法随机收集我科收治的50例孕34~36;周需终止妊娠的孕妇,采集其胎儿经胸标准四腔心切面图像,统计数据包括测量数据:左右肺面积、心脏面积、胸廓面积及胸围、左右肺纵径;计算数据:心脏面积/总肺面积,总肺体积、分析早产胎儿肺纹理特征,得到胎儿肺成熟度结果,肺成熟度分析系统为GE Voluson E8,并分为高风险组、低风险组,采用糖皮质激素促胎肺成熟的胎儿定义为用药组,分析胎儿肺部超声与晚期早产儿呼吸系统疾病相关性,以及灵敏度、特异度。结果非用药组胎儿的呼吸系统疾病发生率明显高于用药组和低风险胎儿(P<0.05),而用药组和低风险胎儿的呼吸系统疾病发生率相似(P>0.05)。相关性分析得知,晚期早产儿呼吸系统疾病与全自动胎儿肺部超声结果具有相关性,风险高的患者,肺面积、总肺体积等发育迟缓的患者容易发生呼吸系统疾病。全自动胎儿肺部超声分析胎儿呼吸系统疾病的灵敏度为62.50%、特异度为40.48%。结论全自动胎儿肺部超声分析结果可很好地预估晚期早产儿呼吸系统情况,对于早期干预治疗提供很好证据,可向临床推荐。 相似文献
9.
目的 筛选荔枝草治疗急性咽炎的有效部位,研究治疗急性咽炎的作用机制,为荔枝草资源的药食两用开发提供理论依据。方法 通过二甲苯致小鼠耳肿胀试验筛选荔枝草抗炎有效部位,采用氨水刺激喉部法建立大鼠急性咽炎模型,通过行为学观察、ELISA双抗夹心检测、病理形态学观察和咽部组织蛋白表达研究乙酸乙酯部位对大鼠急性咽炎的治疗效果。结果 荔枝草乙酸乙酯提取物对二甲苯致小鼠耳肿胀有明显的抑制作用,氨水刺激建立的急性咽炎模型符合急性咽炎动物模型特征,乙酸乙酯部位提取物可显著改善急性咽炎大鼠的咽部病理形态学表现。不同剂量治疗组大鼠血清及咽部组织中IL-1β、IL-6及TNF-α炎性因子数量均下降,高剂量组下降最为明显。荔枝草乙酸乙酯提取物可明显增加大鼠咽部组织IκBα蛋白表达,降低NF-κBp65蛋白表达。结论 荔枝草乙酸乙酯部位提取物对急性咽炎具有治疗作用,可能与抑制咽部炎症病理改变的发生,能调节血液中炎症因子、抑制NF-κB表达和IκBα解离有关。 相似文献
10.
《Taiwanese journal of obstetrics & gynecology》2022,61(4):641-645
ObjectiveNerve-sparing radical hysterectomy (NSRH) decreases the negative postoperative consequences of radical surgery for cervical cancer, such as bladder evacuation disorders, colorectal motility disorders, and sexual dysfunction. The aim of this study was to prospectively assess the sexuality and quality of life in a group of women who underwent NSRH with lymphadenectomy for cervical cancer.Materials and methodsA total of 65 patients with early-stage cervical cancer underwent NSRH between 2014 and 2016. Patient examinations and questionnaire surveys (Female Sexual Function Index questionnaire and European Organization for Research and Treatment of Cancer questionnaires QLQ-C30 and QLQ-CX24) were conducted, before and one year after the surgery.ResultsAfter the exclusion of 19 sexually inactive women and 10 women who received adjuvant anticancer treatment, 36 sexually active patients treated solely with nerve-sparing surgery were eligible for evaluation. The mean age was 47 years. The average preoperative vaginal length was 9.4 cm, whereas the postoperative length was shortened to 7.1 cm. This study showed no negative impact of NSRH on sexual desire, arousal, satisfaction, orgasm, pain, sexual activity, sexual enjoyment, and sexual worry. The worsening of sexual functioning was recorded during the one-year follow-up. The QLQ-C30 questionnaire confirmed postoperative improvement in global health status and role, emotional, and social functioning.ConclusionOur study showed using standardized questionnaires that NSRH has no negative impact on sexual desire, arousal, satisfaction, orgasm, pain, sexual activity, frequency of sexual intercourse, sexual enjoyment, and sexual worry, while only the worsening of sexual functioning was recorded. Moreover, NSRH did not cause postoperative deterioration in the quality of life parameters. 相似文献