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In this paper, we combine the nonlinear HWENO reconstruction in [43] and the fixed-point iteration with Gauss-Seidel fast sweeping strategy, to solve the static Hamilton-Jacobi equations in a novel HWENO framework recently developed in [22]. The proposed HWENO frameworks enjoys several advantages. First, compared with the traditional HWENO framework, the proposed methods do not need to introduce additional auxiliary equations to update the derivatives of the unknown function $\phi$. They are now computed from the current value of $\phi$ and the previous spatial derivatives of $\phi$. This approach saves the computational storage and CPU time, which greatly improves the computational efficiency of the traditional HWENO scheme. In addition, compared with the traditional WENO method, reconstruction stencil of the HWENO methods becomes more compact, their boundary treatment is simpler, and the numerical errors are smaller on the same mesh. Second, the fixed-point fast sweeping method is used to update the numerical approximation. It is an explicit method and does not involve the inverse operation of nonlinear Hamiltonian, therefore any Hamilton-Jacobi equations with complex Hamiltonian can be solved easily. It also resolves some known issues, including that the iterative number is very sensitive to the parameter $ε$ used in the nonlinear weights, as observed in previous studies. Finally, to further reduce the computational cost, a hybrid strategy is also presented. Extensive numerical experiments are performed on two-dimensional problems, which demonstrate the good performance of the proposed fixed-point fast sweeping HWENO methods.  相似文献   
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AimTo examine the effectiveness of a Humanoid Diagram Teaching Strategy (HDTS) on care capabilities and retention of novice nurses.BackgroundGuiding novice nurses in clinical practice is a matter of concern and the use of diagrams in assisting the learning process and to promote learning efficiency has been acknowledged.DesignThis is a quasi-experimental study with asynchronous repeated measurements for the experimental and control groups.MethodsThe study was conducted in a medical centre in southern Taiwan with 24 novice nurses. The intervention, Humanoid Diagrams Teaching Strategy, contained three parts: the head and neck; trunk; and limbs. The HDTS was applied three time weekly. Each session lasted approximately 30 min and the training lasted 4 weeks. The effectiveness of HDTS was measured using Mini-CEX, CbD and retention rates in the 3rd and 6th months of novice nurses’ experience.ResultsAfter the HDTS, although increases in mini-CEX and CbD scores in the experimental group were greater than the control group, these differences were not statistically significant after considering the time interaction. But the 3rd month and 6th month novice nurses’ retention rates were statistically significantly different by comparing the differences under the time interaction effects in both groups.ConclusionsThe Humanoid Diagram Teaching Strategy is an effective tool for preceptors to use in assisting novice nurses in learning, improving their nursing care knowledge and technical skills and to increase their retention rate.  相似文献   
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目的 多样的环境因素使得不同产地栽培滇重楼的化学成分也丰富多样,不同居群栽培滇重楼的甾体皂苷类成分具有很大的差异,多源数据融合分析能更全面的表征药材化学信息,建立一个高效而准确的产地鉴别模型,为其资源合理开发利用提供依据。方法 以来自云南和四川的8个产地(保山、楚雄、大理、红河、丽江、成都、文山、玉溪)共366份栽培滇重楼根茎为实验材料,采集其傅里叶变换近红外光谱(FT-NIR)和衰减全反射-傅里叶变换中红外光谱(ATR-FTMIR)数据。采用Kennard-Stone算法将不同产地的样品分为2/3的训练集和1/3的预测集,基于4种特征变量提取方法(CARS、VIP、SPA、SO-Covsel)结合2种数据融合策略(低级数据融合和中级数据融合),建立偏最小二乘产地判别分析模型。根据模型参数交叉验证均方根误差(RMSECV)和预测均方根误差(RMSEP)评估模型的稳定性,模型训练集和预测集准确率(ACC)评估模型分类性能。结果 近红外光谱和中红外光谱均能反应不同产地栽培滇重楼的化学成分差异,在中级数据融合中,基于VIP和SPA提取的特征变量建立的模型正确率均大于94%。相较于中级数据融合,低级数据融合模型得到了最为满意的结果,其预测集分类正确率达到100%。结论 根据近红外和中红外数据建立的低级数据融合PLS-DA模型,能够用于栽培滇重楼的产地鉴别分析。  相似文献   
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目的 探究大学生微信朋友圈人格、自我呈现策略和情绪表达间的关系。方法 采用社交网络自我呈现策略问卷、艾森克人格问卷简式量表、伯克利情绪表达问卷,对随机抽取的371名大学生进行调查。结果 ⑴外倾型人格总分与真实自我呈现策略总分呈正相关(r=0.170,P=0.001),与正性情绪表达呈正相关(r=0.166,P=0.001),与情绪表达强度呈正相关(r=0.184,P=0.001),真实自我呈现策略与正性情绪表达呈正相关(r=0.239,P=0.001)。⑵真实自我呈现策略在外倾型人格与正性情绪表达的关系中存在部分中介效应。结论 371名大学生的外倾型人格、真实自我呈现策略与正性情绪表达关系密切,真实自我呈现策略在外倾型人格与正性情绪表达的关系中存在部分中介效应。  相似文献   
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《Drug discovery today》2022,27(1):246-256
Bromodomain-containing protein 4 (BRD4) is emerging as a therapeutic target that acts synergistically with other targets of small-molecule drugs in cancer. Therefore, the discovery of potential new dual-target inhibitors of BRD4 may be a promising strategy for cancer therapy. In this review, we highlight a series of strategies to design therapeutic dual-target inhibitors of BRD4 that focus on the synergistic functions of this protein. Drug combinations that exploit synthetic lethality, protein–protein interactions, functional complementarity, and blocking of resistance mechanisms could ultimately overcome the barriers inherent to the development of BRD4 inhibitors as future cancer drugs.  相似文献   
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目的 探讨路径式营养管理在食管癌围术期患者中的应用效果。方法 选取2018年1月至2018年7月在四川省肿瘤医院胸外科接受食管癌根治手术治疗的患者156例,随机分为干预组(n=78)和对照组(n=78),干预组采用路径式营养管理,对照组采用常规营养管理,比较两组患者在术后7d血红蛋白、前白蛋白、体质指数(BMI)、预后营养指数(PNI)等营养指标、术后并发症发生率及术后住院时间。结果 干预组患者术后7d血红蛋白(126.09±16.69)g/L、前白蛋白(208.74±38.51)mg/L、BMI(22.28±2.05)kg/m2、PNI(46.62±4.03)优于对照组,差异有统计学意义(P<0.05);干预组患者胸腔积液发生率低于对照组,差异有统计学意义(t=4.02,P=0.04);干预组患者住院时间短于对照组,差异有统计学意义(t=6.53,P=0.03)。结论 路径式营养管理能有效改善食管癌围术期患者营养状况、降低并发症发生率、缩短术后住院时间。  相似文献   
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适宜性产区能够保障傣族药的品质,然而有关植物类傣族药适宜生态因子及适宜产区的研究目前较为匮乏。本研究利用中药材产地适宜性分析地理信息系统(GMPGIS)对植物类傣族药进行全国产地生态适宜性分析,首次提出了植物类傣族药主要分布区域的生态因子范围和主要土壤类型,如年均温8. 6~23. 7℃,年均降水量1 212~1 881 mm,年均日照149. 7~157. 4 W·m-2,主要土壤类型为强淋溶土、冲积土、高活性强酸土等。以179个采样点为基础,通过生态相似性分析得到植物类傣族药在全球范围内的最大生态相似度区域,主要包括中国、巴西、美国、缅甸、老挝等国家。在中国主要集中在云南的西部和南部,包括西双版纳傣族自治州、德宏傣族景颇族自治州普洱市、保山市、临沧市具有较大的适宜栽培区域。除此之外,本文通过分析傣族药人才匮乏、傣族药资源日益减少、文化传承具有局限性、科学研究薄弱等问题,并提出了通过傣族医药高素质人才培养、傣族药资源调研和保护工作、推进傣族药资料古籍的搜集整理、加强傣族药基础研究和应用研究等策略促进傣族医药发展。本研究为指导植物类傣族药生产基地合理布局、引种繁育等提供依据,为高品质傣族药的科学规范化生产奠定基础。  相似文献   
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COVID-19 has become a pandemic and it has already spread to at least 171 countries/regions. Chronic kidney disease (CKD) is a global public health problem with a total of approximately 850 million patients with CKD worldwide and 119.5 million in China. Severe COVID-19 infection may damage the kidney and cause acute tubular necrosis, leading to proteinuria, hematuria and elevated serum creatinine. Since the SARS-CoV-2 enters the cells by binding to the angiotensin-converting enzyme 2 receptor, some doctors question its ability to increase the risk and severity of developing COVID-19. Neither clinical data nor basic scientific evidence supports this assumption. Therefore, patients who take angiotensin-converting enzyme inhibitor or angiotensin receptor blocker are not advised to change their therapy. Patients with CKD are generally the elderly population suffering from multiple comorbidities. Moreover, some patients with CKD might need to take glucocorticoids and immunosuppressants. Dialysis patients are recurrently exposed to a possible contaminated environment because their routine treatment usually requires three dialysis sessions per week. Considering all the above reasons, patients with CKD are more vulnerable to COVID-19 than the general population. The development of COVID-19 may worsen the impaired kidney function and further lead to rapid deterioration of kidney function and even death. Strict comprehensive protocols should be followed to prevent the spread of COVID-19 among patients with CKD. In this review, we provide some practical management recommendations for health care providers, patients with CKD, dialysis patients and dialysis facilities.  相似文献   
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