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Simple and effective method for treating severe adult skeletal class II malocclusion: A case report
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作者 Li-Li Xie Dan-Yang Chu Xiao-Feng Wu 《World Journal of Orthopedics》 2024年第10期965-972,共8页
BACKGROUND Severe skeletal class II malocclusion is the indication for combined orthodontic and orthognathic treatment.CASE SUMMARY A woman with a chief complaint of a protruding chin and an inability to close her lip... BACKGROUND Severe skeletal class II malocclusion is the indication for combined orthodontic and orthognathic treatment.CASE SUMMARY A woman with a chief complaint of a protruding chin and an inability to close her lips requested orthodontic camouflage.The treatment plan consisted of extracting the right upper third molar,right lower third molar,left lower second molar,and left upper third molar and moving the maxillary dentition distally using a convenient method involving microimplant nail anchors,push springs,long arm traction hooks,and elastic traction chains.After 52 months of treatment,her overbite and overjet were normal,and her facial profile was favorable.CONCLUSION This method can be used for distal movement of the maxillary dentition and to correct severe skeletal class II malocclusion in adults. 展开更多
关键词 Skeletal class II malocclusion Maxillary dentition Microimplant nail simple and effective method Case report
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An Affordable and Easily Accessible Approach for Acrylonitrile Monomer Purification through a Simple Column Technique
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作者 Rawdah Whba Mohd Sukor Su’ait Azizan Ahmad 《Journal of Materials Science and Chemical Engineering》 2024年第4期18-28,共11页
This manuscript presents a dataset detailing a method for purifying monomers. Purification plays a crucial role in every chemical process, as it leads to an improvement in product quality through the removal of impuri... This manuscript presents a dataset detailing a method for purifying monomers. Purification plays a crucial role in every chemical process, as it leads to an improvement in product quality through the removal of impurities. The primary method for monomer purification, like acrylonitrile (AN), is the distillation technique. However, this technique is unsafe and hard to set up or handle. A straightforward, risk-free, low-cost method like the column technique resolves these issues. A simple column technique demonstrated the successful execution of purifying AN. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) analyses confirmed that AN was successfully purified, with purity reaching 99.8%. FTIR spectra revealed changes in the position and intensity of the stretching vibration peaks after purification. Also, the functional groups of the inhibitor monomethyl ether of hydroquinone (MeHQ) were undetected after purification. Furthermore, after purification, NMR spectra revealed the absence of aromatic protons and carbons associated with MeHQ. In conclusion, the column technique is a successful and inexpensive way to purify AN monomers. This makes it useful for a wide range of applications, especially in polymerization reactions where MeHQ needs to be removed to prevent self-polymerization during the initiation process. 展开更多
关键词 Liquid Monomers ACRYLONITRILE PURIFICATION Inhibitor simple Column
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Heat Kernel Estimates on Simple Random Walks and On-Diagonal Upper Bounds
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作者 Runquan Zuo Yuxiao Yan +2 位作者 Zishan Zhu Liwen Yao Qihao Han 《Journal of Applied Mathematics and Physics》 2024年第10期3613-3625,共13页
We primarily provide several estimates for the heat kernel defined on the 2-dimensional simple random walk. Additionally, we offer an estimate for the heat kernel on high-dimensional random walks, demonstrating that t... We primarily provide several estimates for the heat kernel defined on the 2-dimensional simple random walk. Additionally, we offer an estimate for the heat kernel on high-dimensional random walks, demonstrating that the heat kernel in higher dimensions converges rapidly. We also compute the constants involved in the estimate for the 1-dimensional heat kernel. Furthermore, we discuss the general case of on-diagonal estimates for the heat kernel. 展开更多
关键词 Heat Kernel simple Random Walk On-Diagonal Estimate
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Life′s Simple 7干预减轻Her⁃2阳性乳腺癌患者化疗相关心血管系统损害的研究 被引量:2
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作者 吴军 崔伟燕 +2 位作者 李平 张青凤 欧月珍 《实用医学杂志》 CAS 北大核心 2023年第13期1647-1651,1656,共6页
目的探讨Life′s Simple 7(LS7)干预减轻Her⁃2阳性乳腺癌患者根治术后化疗相关心血管系统损害的作用。方法将120例Her⁃2阳性并接受标准化乳腺癌化疗的患者随机等量分为对照组及LS7组,对照组为标准化疗方案,LS7组为对照组基础上给予LS7干... 目的探讨Life′s Simple 7(LS7)干预减轻Her⁃2阳性乳腺癌患者根治术后化疗相关心血管系统损害的作用。方法将120例Her⁃2阳性并接受标准化乳腺癌化疗的患者随机等量分为对照组及LS7组,对照组为标准化疗方案,LS7组为对照组基础上给予LS7干预12个月,后续通过比较两组治疗前后心血管系统损伤程度、焦虑、抑郁及生活质量等指标评价其对心血管系统损害的改善作用。结果相较于对照组,LS7组LS7总评分及7项心血管健康指标均优于对照组(P<0.05),LS7组LVEF较高(P<0.05)、NT⁃proBNP较低(P<0.05),焦虑和抑郁评分较低(P<0.05)、生活质量评分较高(P<0.05)。结论LS7干预可显著减轻Her⁃2阳性乳腺癌化疗相关心血管系统损害并改善乳腺癌患者的心理状况和生活质量,值得在临床推广。 展开更多
关键词 Life′s simple 7 乳腺癌 心血管健康 心理状况 生活质量
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Simple shear extrusion versus equal channel angular pressing:A comparative study on the microstructure and mechanical properties of an Mg alloy 被引量:2
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作者 A.Rezaei R.Mahmudi +1 位作者 C.Cayron R.E.Logé 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第5期1769-1790,共22页
Two severe plastic deformation(SPD)techniques of simple shear extrusion(SSE)and equal channel angular pressing(ECAP)were employed to process an extruded Mg-6Gd-3Y-1.5Ag(wt%)alloy at 553 K for 1,2,4 and 6 passes.The mi... Two severe plastic deformation(SPD)techniques of simple shear extrusion(SSE)and equal channel angular pressing(ECAP)were employed to process an extruded Mg-6Gd-3Y-1.5Ag(wt%)alloy at 553 K for 1,2,4 and 6 passes.The microstructural evolutions were studied by electron back scattered diffraction(EBSD)analysis and transmission electron microscopy(TEM).The initial grain size of 7.5μm in the extruded alloy was reduced to about 1.3μm after 6 SPD passes.Discontinuous dynamic recrystallization was suggested to be operative in both SSE and ECAP,with also a potential contribution of continuous dynamic recrystallization at the early stages of deformation.The difference in the shear strain paths of the two SPD techniques caused different progression rate of dynamic recrystallization(DRX),so that the alloys processed by ECAP exhibited higher fractions of recrystallization and high angle grain boundaries(HAGBs).It was revealed that crystallographic texture was also significantly influenced by the difference in the strain paths of the two SPD methods,where dissimilar basal plane texture components were obtained.The compression tests,performed along extrusion direction(ED),indicated that the compressive yield stress(CYS)and ultimate compressive strength(UCS)of the alloys after both SEE and ECAP augmented continuously by increasing the number of passes.ECAP-processed alloys had lower values of CYS and UCS compared to their counterparts processed by SSE.This difference in the mechanical responses was attributed to the different configurations of basal planes with respect to the loading direction(ED)of each SPD technique. 展开更多
关键词 Mg-Gd-Y alloys Severe plastic deformation simple shear extrusion Equal channel angular pressing Dynamic recrystallization Mechanical properties
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成年人Life's Simple 7和非酒精性脂肪性肝病之间的关联
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作者 曾冠男 陈容容 卢世云 《中国医药指南》 2023年第21期29-32,共4页
目的探究成年人中Life's Simple 7与非酒精性脂肪性肝病(NAFLD)之间的关联。方法数据来自2017-2018年国家健康和营养检查调查(NHANES)中招募的成年人。排除HBsAg阳性、抗-HCV阳性和大量饮酒后,通过肝脏振动控制瞬时弹性成像(VCTE)对... 目的探究成年人中Life's Simple 7与非酒精性脂肪性肝病(NAFLD)之间的关联。方法数据来自2017-2018年国家健康和营养检查调查(NHANES)中招募的成年人。排除HBsAg阳性、抗-HCV阳性和大量饮酒后,通过肝脏振动控制瞬时弹性成像(VCTE)对NAFLD进行诊断。参考既往的研究计算Life's Simple 7,0~8分为低分组(inadequate),9~10分为平均组(average),11~14分为优秀组(optimal)。进行多因素Logistic回归分析相关性。结果分析了2376名参与者的数据。NAFLD的总患病率为42.0%,在inadequate、average和optimal评分类别中的患病率分别为62.5%、33.4%和10.8%(P<0.001)。多因素Logistics回归分析,调整了年龄、性别、种族和贫困收入比率(PIR)后显示Life's Simple 7得分越高,NAFLD患病风险降低。跟inadequate组对比,average组OR值为0.31(95%CI:0.23-0.42),optimal组的OR值为0.08(95%CI:0.05-0.13)。根据分层分析,这种关联在不同年龄、性别、种族和经济群体中是相似的。结论越高的Life's Simple 7评分与越低的NAFLD患病率相关。拥有理想的心血管健康指标可能有利于降低普通成年人NAFLD的患病率。 展开更多
关键词 Life's simple 7 非酒精性脂肪性肝病
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基于Simple Seasonal模型上网电量和厂用电量的发电量预测 被引量:1
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作者 李雍睿 禹加 杨朔 《电力系统装备》 2023年第3期37-40,共4页
近年来,预测发电量统计引起国家电网的高度关注。供电企业对发电量进行预测,不仅能满足社会用电要求,还能提高企业的竞争力。文章以辽宁省的两个火电厂为例,采用Simple Seasonal模型预测未来1个月的上网电量和厂用电量,进而统计发电量... 近年来,预测发电量统计引起国家电网的高度关注。供电企业对发电量进行预测,不仅能满足社会用电要求,还能提高企业的竞争力。文章以辽宁省的两个火电厂为例,采用Simple Seasonal模型预测未来1个月的上网电量和厂用电量,进而统计发电量的预测值。在确保电网安全前提下,不仅可以保障电力供应平稳有序,最大限度减少因无序用电带来的损失,还可以为节约用电开辟一条新的道路。 展开更多
关键词 simple Seasonal 上网电量 厂用电量 发电量 预测 时间序列
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基于SIMPLE药学服务模式的药物指导在呼吸内科慢性病患者用药管理中的效果评估
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作者 于盼盼 《中国科技期刊数据库 医药》 2023年第9期51-54,共4页
对基于SIMPLE药学服务模式的药物指导应用于呼吸内科慢性病患者用药管理中的应用效果进行评估。方法 自我院2021年8月~2022年8月间收治的呼吸内科慢性病患者中随机抽选本次研究对象,筛选后符合相关标准的共计108例,组织患者集中抽签,分... 对基于SIMPLE药学服务模式的药物指导应用于呼吸内科慢性病患者用药管理中的应用效果进行评估。方法 自我院2021年8月~2022年8月间收治的呼吸内科慢性病患者中随机抽选本次研究对象,筛选后符合相关标准的共计108例,组织患者集中抽签,分别设置红色球54颗,黄色球54颗,抽到红色球的患者进入研究组,抽到黄色球的患者进入对照组,由此每组可均分54例。对照组患者接受常规药学服务模式下的药物指导,研究组患者则基于SIMPLE药物服务模式进行药物指导,对两种模式取得的临床效果展开对比。结果 干预进行至第3个月与第6个月时,所有患者在吸入装置使用方面的评分较前有所改善,但研究组患者的评分更高(P<0.05);干预进行至第3个月与第6个月时,所有患者的肺功能指标逐渐好转,对比研究组与对照组数据,发现研究组更具优势(P<0.05);干预结束时,研究组患者在安全用药方面的评价明显高于对照组,各维度评分均表现出显著差异(P<0.05);干预期间,研究组患者更少出现不良反应,组间数据对比:研究组(3.70%)vs对照组(20.37%)有明显优势(P<0.05)。结论 基于SIMPLE药学服务模式的药学指导能够规范呼吸内科慢性病患者的用药行为,提升其吸入装置使用能力,改善患者的临床症状,有较高的临床应用价值。 展开更多
关键词 simple药学服务模式 药物指导 呼吸内科慢性病 用药管理
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Symmetry phases of asymmetric simple exclusion processes on two lanes with an intersection
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作者 田波 文万强 +1 位作者 李阿敏 夏萍 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期317-324,共8页
This paper studies two-lane asymmetric simple exclusion processes(ASEPs)with an intersection.In the upstream segments of the intersection,one particle can move to the next site with rate 1 if the site is empty,and the... This paper studies two-lane asymmetric simple exclusion processes(ASEPs)with an intersection.In the upstream segments of the intersection,one particle can move to the next site with rate 1 if the site is empty,and the other particle can move forward with rate p in the sites of downstream segments.The parameter p can represent the rate of slowing of motion,and the parameter is introduced to investigate spontaneous symmetry breaking(SSB)phenomenon.Extensive Monte Carlo simulations are carried out.It is shown that three symmetric phases exist and the SSB does not exist in the system.Simple mean field approach in which correlation of sites is ignored is firstly adopted to analyze the system,and the system is divided into four independent segments.It is found that the analytical results deviate from the simulation ones,especially when p is small.In addition,the inexsitence of SSB can only be explained qualitatively.Motivated by this,we carry out the cluster mean field analysis in which correlation of five sites is considered.It is shown that densities of the two upstream segments are equal,which demonstrates that the SSB does not exist.It is also shown that,as expected,the cluster mean field analysis performs much better than the simple mean field analysis. 展开更多
关键词 asymmetric simple exclusion process spontaneous symmetry breaking simple mean-field analysis cluster mean-field analysis
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PD-like finite time controller with simple structure for satellite attitude control
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作者 Li You Ye Dong Xiao Bing 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期123-133,共11页
A finite time controller with PD-like structure for satellite attitude control is proposed in this paper.The controller is constructed with simple structure based on standard PD controller.The fractional order term is... A finite time controller with PD-like structure for satellite attitude control is proposed in this paper.The controller is constructed with simple structure based on standard PD controller.The fractional order term is designed hence system could both have strong robustness and finite time convergence rate,and the advantage of finite time control and PD control is combined in this paper.System convergence rate is discussed by Lyapunov method,and the constraint on control parameters is given by implementing the coupled term of angular velocity and attitude quaternion.Moreover,the accuracy at steady stage depending on control parameters is given hence system could converge to this field within finite time.System stability and performance is demonstrated by numerical simulation results. 展开更多
关键词 Finite time control PD-like simple structure Attitude control
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Molecular characterization of sweet potato(Ipomoea batatas[L.]Lam)germplasms for desirable traits by using simple sequence repeats markers
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作者 KHANDAKAR ABUMDMOSTAFIZAR RAHMAN ABDUL SHUKOR JURAIMI +6 位作者 MDREZWAN MOLLA MUHAMMAD ASYRAFMD HATTA ZULKEFLY BIN SULAIMAN SHAMIMA SULTANA AHMED GABER BENUKAR BISWAS AKBAR HOSSAIN 《BIOCELL》 SCIE 2023年第1期227-237,共11页
Every breeding program that aims to create new and improved cultivars with desired traits mostly relies on information related to genetic diversity.Therefore,molecular characterization of germplasms is important to ob... Every breeding program that aims to create new and improved cultivars with desired traits mostly relies on information related to genetic diversity.Therefore,molecular characterization of germplasms is important to obtain target cultivars with desirable traits.Sweet potato[Ipomoea batatas(L.)Lam]is widely considered the world’s most important crop,with great diversity in morphological and phenotypic traits.The genetic diversity of 20 sweet potato germplasms originating from Bangladesh,CIP,Philippines,Taiwan,and Malaysia were compared,which was accomplished by genetic diversity analysis by exploring 20 microsatellite DNA markers for germplasm characterization and utilization.This information was effective in differentiating or clustering the sweet potato genotypes.A total of 64 alleles were generated using the 20 primers throughout the 20 germplasm samples,with locus IBS97 having the highest number of alleles(5),whereas locus IbU33 had the fewest alleles(2).The alleles varied in size from 105(IbU31)to 213 base pairs(IBS34).The Polymorphism Information Content(PIC)values for the loci IbL46 and IBS97 varied from 0.445 to 0.730.IBS97 has the highest number of effective alleles(3.704),compared to an average of 2.520.The average Shannon’s diversity index(H)was 1.003,ranging from 0.673 in IbU3 to 1.432 in IBS97.The value of gene flow(Nm)varied between 0.000 and 0.005,with an average of 0.003,whereas genetic differentiation(FST-values)ranged between 0.901 and 1.000.The sweet potato germplasm included in this study had a broad genetic base.SP1 vs.SP9 and SP12 vs.SP18 germplasm pairings had the greatest genetic distance(GD=0.965),while SP1 vs.SP2 germplasm couples had the least genetic diversity(GD=0.093).Twenty genotypes were classified into two groups in the UPGMA dendrogram,with 16 genotypes classified as group“A”and the remaining four genotypes,SP10,SP18,SP19,and SP20,classified as group“B.”According to cluster analysis,the anticipated heterozygosity(gene diversity)of Nei(1973)was 0.591 on average.In summary,SSR markers successfully evaluated the genetic relationships among the sweet potato accessions used and generated a high level of polymorphism.The results of the present study will be useful for the management of germplasm,improvement of the current breeding strategies,and the release of new cultivars as varieties. 展开更多
关键词 Sweet potato simple sequence repeats(SSRs) Genetic diversity DENDROGRAM
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A Class of Simple Modules for Electrical Lie Algebra of Type D_(5)
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作者 陈雨露 申冉 张建刚 《Journal of Donghua University(English Edition)》 CAS 2023年第2期232-236,共5页
The simple modules for electrical Lie algebra of type D5 were investigated.The sufficient and necessary criteria of the simple Z-graded highest weight modules were established by means of determining the singular vect... The simple modules for electrical Lie algebra of type D5 were investigated.The sufficient and necessary criteria of the simple Z-graded highest weight modules were established by means of determining the singular vectors of the Verma modules.The simple highest weight module is isomorphic to either that for the symplectic Lie algebra sp4 or Verma module. 展开更多
关键词 electrical Lie algebra simple module highest weight module
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A Simple One-Step System Enhances the Availability of High-Quality Sperm for Assisted Reproductive Procedures
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作者 Sam Prien Trinity Moseley +3 位作者 Nirvika Singh-Sharma Juergen Liebermann Matthew D. VerMilyea Lindsay L. Penrose 《Open Journal of Obstetrics and Gynecology》 2023年第10期1676-1687,共12页
Over the last forty years, in vitro fertilization, which has expanded to assisted reproductive technologies (ART), has gone from an experimental procedure to the mainstay of infertility treatment. A technique that onc... Over the last forty years, in vitro fertilization, which has expanded to assisted reproductive technologies (ART), has gone from an experimental procedure to the mainstay of infertility treatment. A technique that once made news with each birth is now responsible for 2% - 3% of the babies born in several nations of the world. This has happened due to significant advances in hormone therapies, culture techniques, and the specialization of equipment designed to support oocytes and embryos. However, for all the advances made to support female fertility, little has changed in male treatment since the advent of intracytoplasmic sperm injection in the early 1990’s. Recently, a number of authors have documented problems with sperm preparation techniques. Some report DNA damage, others membrane and organelle issues, all of which potentially hamper fertilization rates and possibly take-home baby rates. Further, as the clinical workload of ART has increased and staffing shortages have become critical, all labs are looking for simpler, more efficient ways to perform job functions. This study describes a simple, one-step method for preparing semen samples for ART. This new technique minimizes excessive manipulation of the sample compared to current standards and is less likely to cause cell damage. Preliminary results suggest a significant enhancement in recovered sample motility and an optimal sample for ART procedures with minimal sample manipulation. 展开更多
关键词 simple Enhanced SPERM Processing
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Hopf Algebra of Labeled Simple Graphs
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作者 Jiaming Dong Huilan Li 《Open Journal of Applied Sciences》 CAS 2023年第1期120-135,共16页
A lot of combinatorial objects have a natural bialgebra structure. In this paper, we prove that the vector space spanned by labeled simple graphs is a bialgebra with the conjunction product and the unshuffle coproduct... A lot of combinatorial objects have a natural bialgebra structure. In this paper, we prove that the vector space spanned by labeled simple graphs is a bialgebra with the conjunction product and the unshuffle coproduct. In fact, it is a Hopf algebra since it is graded connected. The main conclusions are that the vector space spanned by labeled simple graphs arising from the unshuffle coproduct is a Hopf algebra and that there is a Hopf homomorphism from permutations to label simple graphs. 展开更多
关键词 Hopf Algebra Labeled simple Graph Conjunction Product Unshuffle Coproduct Compatibility
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基于并行BICGSTAB的不可压流场计算方法
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作者 陈涛 《科技创新与应用》 2024年第25期149-152,156,共5页
不可压缩流动广泛存在于日常生活及工程应用之中,随着数值模拟规模不断扩大,CFD算法越来越重视并行计算。该文采用SIMPLE算法对不可压流场进行求解,为求解算法中的大型稀疏矩阵,该文发展一套基于MPI框架的并行BICGSTAB矩阵求解方法。最... 不可压缩流动广泛存在于日常生活及工程应用之中,随着数值模拟规模不断扩大,CFD算法越来越重视并行计算。该文采用SIMPLE算法对不可压流场进行求解,为求解算法中的大型稀疏矩阵,该文发展一套基于MPI框架的并行BICGSTAB矩阵求解方法。最后采用定常顶盖驱动流算例及非定常圆柱绕流算例验证并行算法的可行性及准确性。 展开更多
关键词 不可压缩流动 simple算法 BICGSTAB算法 并行计算 数值模拟
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SIMPLE药学服务模式在支气管哮喘、COPD患者慢病管理中的实践及效果研究 被引量:27
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作者 陈蓉 周磊 +2 位作者 秦琼 宋伟华 包健安 《中国药房》 CAS 北大核心 2018年第10期1400-1403,共4页
目的:将SIMPLE药学服务模式应用于支气管哮喘、慢性阻塞性肺疾病(COPD)患者的慢病管理,并评价其效果。方法:以随机抽样法选取2016年9月-2017年6月在苏州大学附属第一医院呼吸科就诊的支气管哮喘、COPD患者200例,采用简单随机法分成对照... 目的:将SIMPLE药学服务模式应用于支气管哮喘、慢性阻塞性肺疾病(COPD)患者的慢病管理,并评价其效果。方法:以随机抽样法选取2016年9月-2017年6月在苏州大学附属第一医院呼吸科就诊的支气管哮喘、COPD患者200例,采用简单随机法分成对照组(100例)和干预组(100例)。对照组患者予以常规治疗;干预组患者在对照组治疗基础上戒烟、有效使用吸入剂、监控检测指标、正确选择药物、采用科学的生活方式并接受用药宣教。比较两组患者入组时和入组3、6个月后的装置使用评分、肺功能指标[第1秒用力呼气量占预计值的百分比(FEV1%)、第1秒用力呼气占用力肺活量的百分比(FEV1/FVC)]、急性发作/加重患者数、临床有效控制率以及不良反应发生率、装置使用依从性[Morisky用药依从性量表(MMAS-8)评分]。结果:与入组时比较,入组3、6个月后干预组装置使用评分、临床有效控制率、MMAS-8评分显著升高,急性发作/加重≥2次的患者显著减少,差异均有统计学意义(P<0.05)。与对照组比较,入组3、6个月后干预组患者装置使用评分、临床有效控制率、MMAS-8评分、FEV1%显著升高,急性发作/加重≥2次的患者显著减少,差异均有统计学意义(P<0.05)。干预组不良反应发生率显著低于对照组,差异有统计学意义(P<0.05)。结论:采用SIMPLE药学服务模式对支气管哮喘、COPD患者进行慢病管理可提高患者用药依从性和临床疗效,减少不良反应。 展开更多
关键词 支气管哮喘 慢性阻塞性肺疾病 simple药学服务模式 慢病管理
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基于SIMPLE算法的湍流场数值模拟 被引量:16
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作者 赵国智 孔凡让 +2 位作者 占惊春 张志伟 柴华 《水电能源科学》 2007年第3期100-102,共3页
k-ε模型及其双方程模式成功应用于湍流场的流动分析,并使湍流流动的质量、动量、能量基本方程组可以统一表达。SIMPLE算法是流体流场数值模拟的最重要方法。通过VC和MATLAB的混合编程用SIMPLE算法,实现了湍流场的数值模拟。基于SIMPLE... k-ε模型及其双方程模式成功应用于湍流场的流动分析,并使湍流流动的质量、动量、能量基本方程组可以统一表达。SIMPLE算法是流体流场数值模拟的最重要方法。通过VC和MATLAB的混合编程用SIMPLE算法,实现了湍流场的数值模拟。基于SIMPLE算法对一个热流交汇扩散的问题做了数值求解,展示了内部湍流场的分布情况。 展开更多
关键词 湍流 k-ε模型 simple算法 混合编程 数值模拟
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Modeling of surface flux in Tongyu using the Simple Biosphere Model 2 (SiB2) 被引量:4
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作者 延晓冬 李慧阳 +2 位作者 刘飞 高志球 刘辉志 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期183-188,I0005,共7页
The modeling ability of a stand-alone version of the Simple Biosphere Model 2(SiB2) was tested mainly through diagnosing the simulated latent heat(LE),sensible heat(H),CO2 flux,and air temperature at the Tongyu ... The modeling ability of a stand-alone version of the Simple Biosphere Model 2(SiB2) was tested mainly through diagnosing the simulated latent heat(LE),sensible heat(H),CO2 flux,and air temperature at the Tongyu field observation station(44°25'N,122°52'E,184 m elevation) of Coordinated Enhanced Observing Period(CEOP),where the land cover is cropland and grassland.In the whole year of 2003,the canopy height and the leaf area index was variable.During non-growth period,the surface would become bare,while during the growth period,the canopy height could reach 2.0 m high over cropland and 0.8 m high over grassland,respectively,and max leaf area index could reach 4.2 and 2.4,respectively.The model was initialized with measurement and driven by half-hourly atmospheric observations.The simulation values for 2003 were compared against measurements.Results show that the model is of a good ability of simulating the hourly latent heat(LE),sensible heat(H),CO2 flux and temperature during the growth period.Moreover,the daily LE,H and CO2 flux simulated by SiB2 could reflect their yearly change reasonably.However,the model may overestimate the H generally. 展开更多
关键词 CROPLAND GRASSLAND simple Biosphere Model 2(SiB2) surface flux
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非正交同位网格中的SIMPLE算法 被引量:6
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作者 王志东 汪德爟 赖锡军 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2003年第5期509-512,共4页
利用有限体积法建立了非正交同位网格系统中的压力校正方程,详细给出了压力校正方程的离散形式,并对正方腔及倾斜角为45°的斜方腔内流场进行了数值模拟计算.结果表明,非正交同位网格系统中的SIMPLE算法具有编程简单,计算量、存储量... 利用有限体积法建立了非正交同位网格系统中的压力校正方程,详细给出了压力校正方程的离散形式,并对正方腔及倾斜角为45°的斜方腔内流场进行了数值模拟计算.结果表明,非正交同位网格系统中的SIMPLE算法具有编程简单,计算量、存储量小,计算效率高,收敛速度快的优点,可用于几何形状比较复杂流场的计算. 展开更多
关键词 有限体积法 非正交网格 simple算法 水流
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基于非结构化同位网格的SIMPLE算法 被引量:15
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作者 柏威 鄂学全 《计算力学学报》 EI CAS CSCD 北大核心 2003年第6期702-710,共9页
通过基于非结构化网格的有限体积法对二维稳态Navier-Stokes方程进行了数值求解。其中对流项采用延迟修正的二阶格式进行离散;扩散项的离散采用二阶中心差分格式;对于压力-速度耦合利用SIMPLE算法进行处理;计算节点的布置采用同位网格技... 通过基于非结构化网格的有限体积法对二维稳态Navier-Stokes方程进行了数值求解。其中对流项采用延迟修正的二阶格式进行离散;扩散项的离散采用二阶中心差分格式;对于压力-速度耦合利用SIMPLE算法进行处理;计算节点的布置采用同位网格技术,界面流速通过动量插值确定。本文对方腔驱动流、倾斜腔驱动流和圆柱外部绕流问题进行了计算,讨论了非结构化同位网格有限体积法在实现SIMPLE算法时,迭代次数与欠松弛系数的关系、不同网格情况的收敛性、同结构化网格的对比以及流场尾迹结构。通过和以往结果比较可知,本文的方法是准确和可信的。 展开更多
关键词 非结构化网格 同位网格 有限体积法 simple算法 流体力学 流场尾迹结构 边界条件 控制方程 动量方程
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