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The influence of resistance exercise training prescription variables on skeletal muscle mass,strength,and physical function in healthy adults:An umbrella review 被引量:1
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作者 Jonathan C.Mcleod Brad S.Currier +1 位作者 Caroline V.Lowisz Stuart M.Phillips 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期47-60,共14页
Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.Methods:Following ... Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.Methods:Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines,we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass(or its proxies),strength,and/or physical function in healthy adults aged>18 years.Results:We identified 44 systematic reviews that met our inclusion criteria.The methodological quality of these reviews was assessed using A Measurement Tool to Assess Systematic Reviews;standardized effectiveness statements were generated.We found that RT was consistently a potent stimulus for increasing skeletal muscle mass(4/4 reviews provide some or sufficient evidence),strength(4/6 reviews provided some or sufficient evidence),and physical function(1/1 review provided some evidence).RT load(6/8 reviews provided some or sufficient evidence),weekly frequency(2/4 reviews provided some or sufficient evidence),volume(3/7 reviews provided some or sufficient evidence),and exercise order(1/1 review provided some evidence)impacted RT-induced increases in muscular strength.We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass,while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass.There was insufficient evidence to conclude that time of day,periodization,inter-set rest,set configuration,set end point,contraction velocity/time under tension,or exercise order(only pertaining to hypertrophy)influenced skeletal muscle adaptations.A paucity of data limited insights into the impact of RT prescription variables on physical function.Conclusion:Overall,RT increased muscle mass,strength,and physical function compared to no exercise.RT intensity(load)and weekly frequency impacted RT-induced increases in muscular strength but not muscle hypertrophy.RT volume(number of sets)influenced muscular strength and hypertrophy. 展开更多
关键词 HYPERTROPHY Resistance training Resistance training prescription variables STRENGTH Umbrella review
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Numerical Study of the Vibrations of Beams with Variable Stiffness under Impulsive or Harmonic Loading
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作者 Moussa Sali Fabien Kenmogne +1 位作者 Jean Bertin Nkibeu Abdou Njifenjou 《World Journal of Engineering and Technology》 2024年第2期401-425,共25页
The behavior of beams with variable stiffness subjected to the action of variable loadings (impulse or harmonic) is analyzed in this paper using the successive approximation method. This successive approximation metho... The behavior of beams with variable stiffness subjected to the action of variable loadings (impulse or harmonic) is analyzed in this paper using the successive approximation method. This successive approximation method is a technique for numerical integration of partial differential equations involving both the space and time, with well-known initial conditions on time and boundary conditions on the space. This technique, although having been applied to beams with constant stiffness, is new for the case of beams with variable stiffness, and it aims to use a quadratic parabola (in time) to approximate the solutions of the differential equations of dynamics. The spatial part is studied using the successive approximation method of the partial differential equations obtained, in order to transform them into a system of time-dependent ordinary differential equations. Thus, the integration algorithm using this technique is established and applied to examples of beams with variable stiffness, under variable loading, and with the different cases of supports chosen in the literature. We have thus calculated the cases of beams with constant or variable rigidity with articulated or embedded supports, subjected to the action of an instantaneous impulse and harmonic loads distributed over its entire length. In order to justify the robustness of the successive approximation method considered in this work, an example of an articulated beam with constant stiffness subjected to a distributed harmonic load was calculated analytically, and the results obtained compared to those found numerically for various steps (spatial h and temporal τ ¯ ) of calculus, and the difference between the values obtained by the two methods was small. For example for ( h=1/8 , τ ¯ =1/ 64 ), the difference between these values is 17%. 展开更多
关键词 Successive Approximations Method Direct Integration Differential Equations Beams of variable Stiffness Quadratic Parabola Impulse and Harmonic Loads
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基于ICEEMDAN和分布熵的SS-Y伸缩仪信号随机噪声压制方法
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作者 吴林斌 《大地测量与地球动力学》 CSCD 北大核心 2024年第4期429-435,共7页
结合改进的自适应噪声完备集合经验模态分解(ICEEMDAN)与分布熵(DistEn),提出一种无需自定义算法参数、去噪效果较好的伸缩仪信号随机噪声压制方法。首先将伸缩仪信号进行ICEEMDAN处理,得到若干个本征模态函数(IMF);然后计算各IMF分量... 结合改进的自适应噪声完备集合经验模态分解(ICEEMDAN)与分布熵(DistEn),提出一种无需自定义算法参数、去噪效果较好的伸缩仪信号随机噪声压制方法。首先将伸缩仪信号进行ICEEMDAN处理,得到若干个本征模态函数(IMF);然后计算各IMF分量的分布熵值,根据不同分布熵值的大小和表征的分量信号混乱程度,有针对性地对各IMF进行取舍;最后进行线性重构。设计仿真信号去噪实验和SS-Y伸缩仪信号去噪实验,结果表明,基于ICEEMDAN-DistEn去噪模型的伸缩仪信号重构还原度较好,去噪效果显著,明显优于CEEMDAN-DistEn、小波去噪和卡尔曼滤波等去噪模型。 展开更多
关键词 ss-Y伸缩仪 随机噪声压制 改进的自适应噪声完备集合经验模态分解 分布熵 信噪比
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T6SS阳性CRKP临床感染特征及毒力基因分析
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作者 刘莉娟 储雯雯 +4 位作者 王梦 闫涛 龚真 周强 刘周 《中国感染控制杂志》 CAS CSCD 北大核心 2024年第4期488-493,共6页
目的分析T6SS阳性耐碳青霉烯类肺炎克雷伯菌(CRKP)临床感染特征,以及其耐药、毒力基因检出率和生物膜形成能力,为临床防控CRKP感染提供参考数据。方法收集2019年1月—2022年12月安徽某三甲医院临床分离的CRKP菌株及患者资料,PCR法检测T... 目的分析T6SS阳性耐碳青霉烯类肺炎克雷伯菌(CRKP)临床感染特征,以及其耐药、毒力基因检出率和生物膜形成能力,为临床防控CRKP感染提供参考数据。方法收集2019年1月—2022年12月安徽某三甲医院临床分离的CRKP菌株及患者资料,PCR法检测T6SS基因、毒力基因、耐药基因和分子分型,96孔板结晶紫染色法检测生物膜形成能力。结果共纳入160株CRKP。标本来源以痰(46.9%)和血(26.3%)为主。CRKP菌株呈现多重耐药表型,以携带bla KPC(80.6%)为主,其次为bla NDM(17.5%)。根据是否携带T6SS将CRKP分为T6SS阳性组(129株,80.6%)和T6SS阴性组(31株,19.4%)。T6SS阳性组患者患慢性肺部疾病和心脏疾病比例高于T6SS阴性组(P<0.05),且预后较阴性组差(P<0.05)。T6SS阳性组中,iuc A、mrk D、rmp A2、peg 344、wab G、fim H检出率均高于T6SS阴性组(均P<0.05)。CRKP中以ST11型(68.8%)为主,其中K64-ST11型占比70.9%,K47-ST11型占比25.5%。T6SS阳性组ST11型和K64-ST11型CRKP占比均高于T6SS阴性组(均P<0.05)。T6SS阳性组CRKP生物膜形成能力强于T6SS阴性组(P<0.001)。两组除bla OXA-48基因外,在携带其他碳青霉烯类耐药基因和抗菌药物耐药率方面差异无统计学意义。结论该地区CRKP呈现多重耐药,CRKP菌株T6SS检出率高,T6SS阳性CRKP毒力基因检出率更高,且生物膜形成能力更强。 展开更多
关键词 肺炎克雷伯菌 T6ss 毒力基因 耐碳青霉烯类 碳青霉烯酶
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SS-OCT在角膜成像中的应用进展
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作者 赵丽丽 宋继科 +1 位作者 卢秀珍 毕宏生 《国际眼科杂志》 CAS 2024年第7期1058-1063,共6页
成像技术的进步彻底改变了眼科领域,改变了我们对眼科疾病的理解、诊断和治疗。扫频源光学相干断层扫描(SS-OCT)是一种最新的非接触式高分辨率成像技术。它进一步提高了成像深度和扫描速度,增加了新的算法和功能。SS-OCT允许对角膜结构... 成像技术的进步彻底改变了眼科领域,改变了我们对眼科疾病的理解、诊断和治疗。扫频源光学相干断层扫描(SS-OCT)是一种最新的非接触式高分辨率成像技术。它进一步提高了成像深度和扫描速度,增加了新的算法和功能。SS-OCT允许对角膜结构进行三维评估,提供角膜前、后表面的曲率和高度图以及角膜厚度图。这可以帮助眼科医生筛查和诊断角膜病变,如圆锥角膜、角膜营养不良和变性。SS-OCT更快、更精准和更灵敏的角膜测量有助于对即将进行角膜和屈光手术的患者做好术前计划和术后监测。文章总结SS-OCT技术的发展及其在角膜疾病中潜在的临床效用与在手术中的应用进展,以支持更多未来可能的研究和临床治疗。 展开更多
关键词 扫频源光学相干断层扫描(ss-OCT) 屈光手术 角膜移植 散光
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Establishment and Optimization of Status Assessment Variables for Heavy Haul Railway Line Service Performance
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作者 Changfan Zhang Wendong Kong +2 位作者 Zhongmei Wang Lin Jia Shou Chen 《Journal of Transportation Technologies》 2023年第4期731-745,共15页
In order to address the issues of complex system structure and variable selection difficulty for the current heavy haul railway line status evaluation system, a three-category and three-layer heavy-haul line status ev... In order to address the issues of complex system structure and variable selection difficulty for the current heavy haul railway line status evaluation system, a three-category and three-layer heavy-haul line status evaluation variable set construction and reduction optimization method is proposed. Firstly, the status of heavy haul railway line is analyzed, and an initial set of evaluation variables affecting the line status is constructed. Then, based on the association rule and the principal component analysis method, key variables are extracted from the initial variable set to establish the evaluation system. Finally, this method is verified with actual data of a line. The results show that the service performance of heavy haul railway line can still be evaluated accurately when the evaluation variables are reduced by 60% in the proposed method. 展开更多
关键词 Set of variables Key variables Heavy Haul Railway Line Association Rule Principal Component Analysis
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A Broad Range Triboelectric Stiffness Sensor for Variable Inclusions Recognition
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作者 Ziyi Zhao Zhentan Quan +8 位作者 Huaze Tang Qinghao Xu Hongfa Zhao Zihan Wang Ziwu Song Shoujie Li Ishara Dharmasena Changsheng Wu Wenbo Ding 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期298-309,共12页
With the development of artificial intelligence,stiffness sensors are extensively utilized in various fields,and their integration with robots for automated palpation has gained significant attention.This study presen... With the development of artificial intelligence,stiffness sensors are extensively utilized in various fields,and their integration with robots for automated palpation has gained significant attention.This study presents a broad range self-powered stiffness sensor based on the triboelectric nanogenerator(Stiff-TENG)for variable inclusions in soft objects detection.The Stiff-TENG employs a stacked structure comprising an indium tin oxide film,an elastic sponge,a fluorinated ethylene propylene film with a conductive ink electrode,and two acrylic pieces with a shielding layer.Through the decoupling method,the Stiff-TENG achieves stiffness detection of objects within 1.0 s.The output performance and characteristics of the TENG for different stiffness objects under 4 mm displacement are analyzed.The Stiff-TENG is successfully used to detect the heterogeneous stiffness structures,enabling effective recognition of variable inclusions in soft object,reaching a recognition accuracy of 99.7%.Furthermore,its adaptability makes it well-suited for the detection of pathological conditions within the human body,as pathological tissues often exhibit changes in the stiffness of internal organs.This research highlights the innovative applications of TENG and thereby showcases its immense potential in healthcare applications such as palpation which assesses pathological conditions based on organ stiffness. 展开更多
关键词 Stiffness sensor Decoupling method Heterogeneous stiffness variable inclusions Healthcare applications
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偃松PpSS和PpSE基因过表达载体构建
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作者 王思瑶 于宏影 +2 位作者 刘洋 梁雪 南方 《温带林业研究》 2024年第2期68-71,共4页
【目的】构建偃松甾醇代谢途径关键基因SS和SE过表达载体,为促进偃松甾醇高效合成奠定基础,为药用偃松遗传改良提供重要基因资源。【方法】以偃松的cDNA为模板,将SS和SE基因克隆至pNC-Cam1304-35s载体;重组质粒通过PCR及测序鉴定正确后... 【目的】构建偃松甾醇代谢途径关键基因SS和SE过表达载体,为促进偃松甾醇高效合成奠定基础,为药用偃松遗传改良提供重要基因资源。【方法】以偃松的cDNA为模板,将SS和SE基因克隆至pNC-Cam1304-35s载体;重组质粒通过PCR及测序鉴定正确后,三亲杂交转入根瘤农杆菌LBA4404。【结果】抗性农杆菌PCR产物长度与预期一致,阳性菌液测序结果与目标基因序列相同。【结论】成功构建SS和SE过表达载体,重组载体的获得为进一步挖掘其在偃松甾醇代谢中的调控机制研究奠定了基础。 展开更多
关键词 偃松 ss SE 过表达
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Dynamic Analysis of A Deep-Water Compliant Vertical Access Riser with A Variable Length During Installation
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作者 LIANG Wei-xing LOU Min +1 位作者 WANG Yu ZHANG Rui 《China Ocean Engineering》 SCIE EI CSCD 2023年第4期568-579,共12页
Compliant vertical access risers(CVAR)have broad application prospects in deep-water oil and gas transportation.However,the mechanical behaviors of the CVAR with a variable length during installation remains unclear.T... Compliant vertical access risers(CVAR)have broad application prospects in deep-water oil and gas transportation.However,the mechanical behaviors of the CVAR with a variable length during installation remains unclear.To address this issue,based on the flexible segment method,a model of CVAR with a variable length during installation is established in this study,which is verified by the comparison with commercial software.Then,the mechanical behaviors of CVAR during installation are investigated.The results reveal that the CVAR configuration is significantly affected by the buoyancy blocks.The streamwise displacement of CVAR increases with the increase of current velocity.When the BOP weight is insuffcient,obvious upbending is observed in the lower region and transition region,leading to local compression.When the platform moves in the opposite direction to the current,the maximum stress is larger than that of the scenario when the platform moves in the same direction as the current. 展开更多
关键词 compliant vertical access riser installation analysis dynamic performance variable length
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Variable stiffness tuned particle dampers for vibration control of cantilever boring bars
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作者 Xiangying GUO Yunan ZHU +2 位作者 Zhong LUO Dongxing CAO Jihou YANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2163-2186,共24页
This research proposes a novel type of variable stiffness tuned particle damper(TPD)for reducing vibrations in boring bars.The TPD integrates the developments of particle damping and dynamical vibration absorber,whose... This research proposes a novel type of variable stiffness tuned particle damper(TPD)for reducing vibrations in boring bars.The TPD integrates the developments of particle damping and dynamical vibration absorber,whose frequency tuning principle is established through an equivalent theoretical model.Based on the multiphase flow theory of gas-solid,it is effective to obtain the equivalent damping and stiffness of the particle damping.The dynamic equations of the coupled system,consisting of a boring bar with the TPD,are built by Hamilton’s principle.The vibration suppression of the TPD is assessed by calculating the amplitude responses of the boring bar both with and without the TPD by the Newmark-beta algorithm.Moreover,an improvement is proposed to the existing gas-solid flow theory,and a comparative analysis of introducing the stiffness term on the damping effect is presented.The parameters of the TPD are optimized by the genetic algorithm,and the results indicate that the optimized TPD effectively reduces the peak response of the boring bar system. 展开更多
关键词 PARTICLE tuned particle damper(TPD) variable stiffness vibration control
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Numerical Analysis of Flow-Induced Vibration and Noise Generation in a Variable Cross-Section Channel
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作者 Youhao Wang Chuntian Zhe +6 位作者 Chang Guo Jinpeng Li Jinheng Li Shen Cheng Zitian Wu Suoying He Ming Gao 《Fluid Dynamics & Materials Processing》 EI 2023年第12期2965-2980,共16页
Flow channels with a variable cross-section are important components of piping system and are widely used in variousfields of engineering.Using afinite element method and modal analysis theory,flow-induced noise,mode ... Flow channels with a variable cross-section are important components of piping system and are widely used in variousfields of engineering.Using afinite element method and modal analysis theory,flow-induced noise,mode shapes,and structure-borne noise in such systems are investigated in this study.The results demonstrate that the maximum displacement and equivalent stress are located in the part with variable cross-sectional area.The aver-age excitation force on theflow channel wall increases with theflow velocity.The maximum excitation force occurs in the range of 0–20 Hz,and then it decreases gradually in the range of 20–1000 Hz.Additionally,as theflow velocity rises from 1 to 3 m/s,the overall sound pressure level associated with theflow-induced noise grows from 49.37 to 66.37 dB.Similarly,the overall sound pressure level associated with the structure-borne noise rises from 40.27 to 72.20 dB.When theflow velocity is increased,the increment of the structure-borne noise is higher than that of theflow-induced noise. 展开更多
关键词 variable cross-section flow channel noise modal analysis structure-borne noise
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Natural vibration of cantilever porous twisted plate with variable thickness in different directions
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作者 Y.X.Hao Y.Y.Liu +3 位作者 W.Zhang L.T.Liu K.C.Sun S.W.Yang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第9期200-216,共17页
In this paper,the blade is assumed to be a rotating variable thickness cantilever twisted plate structure,and the natural vibrations of variable thickness cantilever twisted plate made of metal porous material are stu... In this paper,the blade is assumed to be a rotating variable thickness cantilever twisted plate structure,and the natural vibrations of variable thickness cantilever twisted plate made of metal porous material are studied.It is assumed that the thickness of the plate changes along spanwise direction and chordwise direction,respectively,and it changes in both directions.The classical thin shell theory,the first and second fundamental forms of surface and von Karman geometric relationship are employed to derive the total potential energy and kinetic energy of the cantilever twisted plate,in which the centrifugal force potential due to high rotational speed is included.Then,according to the Rayleigh-Ritz procedure and applying the polynomial functions which satisfy the cantilever boundary conditions,the dynamic system expressed by equations of motion is reduced to an eigenvalue problem.By numerical simulation,the frequency curves and the mode shapes of the twisted plate can be obtained to reveal the internal connection between natural vibration and the parameters.A series of comparison studies are performed to verify the accuracy of the present formulation and calculations,in which compared data come from experimental,finite element method and theoretical calculation,respectively.The influence of pre-twist angle,three different forms of thickness taper ratio and rotational speed on natural vibration,mode exchange and frequency veering phenomenon of the system is discussed in detail.In addition,the approach proposed here can efficiently extract analytical expressions of mode functions for rotating variable thickness cantilever twisted plate structures. 展开更多
关键词 Porous cantilever twisted plate variable thickness Natural vibration Frequency veering Mode exchange
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Design of Linear Functional Noncircular Gear with High Contact Ratio Used in Continuously Variable Transmission
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作者 Yanan Hu Chao Lin +2 位作者 Chunjiang He Yongquan Yu Zhiqin Cai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第3期205-218,共14页
Continuously variable transmission(CVT)of noncircular gear has the technical advantages of large bearing capacity and high transmission efficiency.The key technology of CVT with noncircular gear has been broken throug... Continuously variable transmission(CVT)of noncircular gear has the technical advantages of large bearing capacity and high transmission efficiency.The key technology of CVT with noncircular gear has been broken through some countries,and is in the stage of deep application research.Although the characteristics and design methods of noncircular gear pairs have been continuously studied in China,the noncircular gear CVT is still in the preliminary exploration and research stage.The linear functional noncircular gear pair,whose transmission ratio is a linear function in the working section,to realize continuously variable transmission was the research object in this paper.According to the required transmission ratio in the working section,the transmission ratio function in the non-working section was constructed by using a polynomial.And then the influence of pitch curve parameters in the working section on which in the non-working section was also analyzed to obtain the pitch curve suitable for transmission of this gear pair.In addition,for improving the stability and bearing capacity of gear transmission,the noncircular gear pair transmission with high contact ratio was designed.Furthermore,the accurate value of the contact tooth length was calculated based on the gear principle and the characteristics of the involute tooth profile,from this the contact tooth length error was calculated by comparing the accurate value with its actual value obtained by the rolling experiment.Finally,an indirect method to verify the contact ratio by detecting the contact length error of the tooth profile was proposed. 展开更多
关键词 Continuously variable transmission Noncircular gear Pitch curve Contact ratio Contact tooth profile
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An Improved HVQ Algorithm for Compression and Rendering of Space Environment Volume Data with Multi-correlated Variables
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作者 BAO Lili CAI Yanxia +2 位作者 WANG Rui ZOU Yenan SHI Liqin 《空间科学学报》 CAS CSCD 北大核心 2023年第4期780-785,共6页
Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research.Space environment simulation can produce several correlated var... Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research.Space environment simulation can produce several correlated variables at the same time.However,existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable,not dealing with the redundant information among these variables.For space environment volume data with multi-correlated variables,based on the HVQ-1d method we propose a further improved HVQ method by compositing variable-specific levels to reduce the redundant information among these variables.The volume data associated with each variable is divided into disjoint blocks of size 43 initially.The blocks are represented as two levels,a mean level and a detail level.The variable-specific mean levels and detail levels are combined respectively to form a larger global mean level and a larger global detail level.To both global levels,a splitting based on a principal component analysis is applied to compute initial codebooks.Then,LBG algorithm is conducted for codebook refinement and quantization.We further take advantage of progressive rendering based on GPU for real-time interactive visualization.Our method has been tested along with HVQ and HVQ-1d on high-energy proton flux volume data,including>5,>10,>30 and>50 MeV integrated proton flux.The results of our experiments prove that the method proposed in this paper pays the least cost of quality at compression,achieves a higher decompression and rendering speed compared with HVQ and provides satisficed fidelity while ensuring interactive rendering speed. 展开更多
关键词 Compressed volume rendering Multi-correlated variables Space environment Vector quantization GPU programming
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SOME RESULTS REGARDING PARTIAL DIFFERENTIAL POLYNOMIALS AND THE UNIQUENESS OF MEROMORPHIC FUNCTIONS IN SEVERAL VARIABLES
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作者 刘曼莉 高凌云 房少梅 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期821-838,共18页
In this paper,we mainly investigate the value distribution of meromorphic functions in Cmwith its partial differential and uniqueness problem on meromorphic functions in Cmand with its k-th total derivative sharing sm... In this paper,we mainly investigate the value distribution of meromorphic functions in Cmwith its partial differential and uniqueness problem on meromorphic functions in Cmand with its k-th total derivative sharing small functions.As an application of the value distribution result,we study the defect relation of a nonconstant solution to the partial differential equation.In particular,we give a connection between the Picard type theorem of Milliox-Hayman and the characterization of entire solutions of a partial differential equation. 展开更多
关键词 meromorphic function in several variables Nevanlinna theory partial differ-ential equation total derivative
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An Adaptive Sequential Replacement Method for Variable Selection in Linear Regression Analysis
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作者 Jixiang Wu Johnie N. Jenkins Jack C. McCarty Jr. 《Open Journal of Statistics》 2023年第5期746-760,共15页
With the rapid development of DNA technologies, high throughput genomic data have become a powerful leverage to locate desirable genetic loci associated with traits of importance in various crop species. However, curr... With the rapid development of DNA technologies, high throughput genomic data have become a powerful leverage to locate desirable genetic loci associated with traits of importance in various crop species. However, current genetic association mapping analyses are focused on identifying individual QTLs. This study aimed to identify a set of QTLs or genetic markers, which can capture genetic variability for marker-assisted selection. Selecting a set with k loci that can maximize genetic variation out of high throughput genomic data is a challenging issue. In this study, we proposed an adaptive sequential replacement (ASR) method, which is considered a variant of the sequential replacement (SR) method. Through Monte Carlo simulation and comparing with four other selection methods: exhaustive, SR method, forward, and backward methods we found that the ASR method sustains consistent and repeatable results comparable to the exhaustive method with much reduced computational intensity. 展开更多
关键词 Adaptive Sequential Replacement Association Mapping Exhaustive Method Global Optimal Solution Sequential Replacement variable Selection
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Optimization of Intermittent Variable Power Microwave Heating Process for Blueberry Pulp
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作者 Xue Liang-liang Gao Rui-li +1 位作者 Song Ruo-nan Zheng Xian-zhe 《Journal of Northeast Agricultural University(English Edition)》 2023年第4期63-74,共12页
To improve heating uniformity and anthocyanin content of the blueberry pulp under microwave heating,the intermittent variable power microwave heating technology was introduced in the study.The effects of technology pa... To improve heating uniformity and anthocyanin content of the blueberry pulp under microwave heating,the intermittent variable power microwave heating technology was introduced in the study.The effects of technology parameters in terms of high microwave intensity heating time,intermittent time,low microwave intensity and low microwave intensity heating time on the blueberry pulp quality parameters(heating uniformity,average moisture content,the highest temperature and anthocyanin content)were investigated by using the response surface method.The results showed that the longer heating time under different microwave intensities resulted in the poorer heating uniformity.The intermittent stage promoted heat and mass transfer within the pulp and reduced the temperature difference and moisture gradient within the pulp,which enhanced desired uniformity of temperature and moisture distribution before entering the low microwave intensity heating stage.Therefore,the longer the intermittent time,the greater the heating uniformity.The optimal parameters were developed as high microwave intensity of 4 W·g^(-1),high microwave intensity heating time of 9.86 min,intermittent time of 10 min,low microwave intensity of 2.2 W·g^(-1)and low microwave intensity heating time of 6 min.This research might provide guidance for microwave heating berry fruits. 展开更多
关键词 blueberry pulp intermittent variable power microwave heating UNIFORMITY ANTHOCYANIN
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高盐饮食通过激活盐皮质受体引发Dahl SS大鼠肾损伤和高血压的新机制
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作者 李曦 王蕊 李洪林 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期391-399,共9页
盐敏感高血压作为一种顽固性高血压,其发病机制十分复杂。虽然盐皮质激素受体激活和肾损伤在盐敏感高血压的发展中起关键作用,但具体的病理机制目前并不明确。通过高盐饮食诱导建立达尔盐敏感(Dahl SS)大鼠高血压模型,探究盐敏感高血压... 盐敏感高血压作为一种顽固性高血压,其发病机制十分复杂。虽然盐皮质激素受体激活和肾损伤在盐敏感高血压的发展中起关键作用,但具体的病理机制目前并不明确。通过高盐饮食诱导建立达尔盐敏感(Dahl SS)大鼠高血压模型,探究盐敏感高血压及肾损伤产生的病理机制。与盐不敏感的SS-13BN大鼠相比,长期高盐饮食会造成Dahl SS大鼠肾脏中交感神经和肾素-血管紧张素-醛固酮系统(RAAS)的局部激活,最终激活盐皮质激素受体(MR),导致上皮钠通道(ENaC)表达增加、氧化应激与炎症反应增强,从而发生肾纤维化病变,并引发肾脏中磷酸化肌动蛋白(P-Cofilin)与足蛋白(Podocin)表达增加,造成足细胞损伤,最终引发肾损伤与高血压症状。 展开更多
关键词 高盐饮食 Dahl ss大鼠 盐敏感高血压 肾损伤 盐皮质激素受体
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血流感染肺炎克雷伯菌Ⅵ型分泌系统(T6SS)的分布及其与毒力和耐药性的相关性分析
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作者 徐玉金 朱亦丹 +4 位作者 李培芬 黄加铭 孙细欢 林颖颖 黄东红 《福建医药杂志》 CAS 2024年第1期45-49,共5页
目的检测Ⅵ型分泌系统(T6SS)在血流感染分离肺炎克雷伯菌中的分布,并分析其与毒力基因、抗生素耐药之间的关系。方法收集我院血培养分离出的肺炎克雷伯菌,通过PCR方法检测T6SS基因、荚膜血清型和毒力基因,并通过VITEKR2 Compact进行药... 目的检测Ⅵ型分泌系统(T6SS)在血流感染分离肺炎克雷伯菌中的分布,并分析其与毒力基因、抗生素耐药之间的关系。方法收集我院血培养分离出的肺炎克雷伯菌,通过PCR方法检测T6SS基因、荚膜血清型和毒力基因,并通过VITEKR2 Compact进行药敏试验。结果56株肺炎克雷伯菌中,26株(46.43%)T6SS阳性。T6SS阳性株中K1、K2荚膜血清型和11个毒力基因的检出率高于T6SS阴性株(P<0.05)。T6SS阳性肺炎克雷伯菌对抗生素更敏感(P<0.05)。HvKP中T6SS阳性率显著高于T6SS阴性率(P<0.05)。从社区和肝脓肿中分离的T6SS阳性肺炎克雷伯菌更多(P<0.05)。糖尿病、携带Aerobactin、rmpA毒力基因是T6SS阳性肺炎克雷伯菌引起血流感染的独立危险因素。结论Ⅵ型分泌系统(T6SS)在引起血流感染的肺炎克雷伯菌中检出率较高,T6SS阳性株携带更多的毒力基因,可能是导致血流感染的主要原因。 展开更多
关键词 肺炎克雷伯菌 血流感染 T6ss 毒力因子 药物敏感性
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基于种特异性COI引物(SS-COI)的桉树枝瘿姬小蜂A、B隐种快速鉴定技术
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作者 王瀚棠 彭欣 杨振德 《环境昆虫学报》 CSCD 北大核心 2024年第4期998-1005,共8页
隐种A和隐种B是桉树枝瘿姬小蜂Leptocybe invasa两种重要的全球入侵隐种,对多国林业生产造成了严重危害。由于桉树枝瘿姬小蜂体型微小,且无法从形态上区分隐种类型,给该害虫的防治造成困难。本研究基于线粒体DNA细胞色素C氧化酶亚基I(mt... 隐种A和隐种B是桉树枝瘿姬小蜂Leptocybe invasa两种重要的全球入侵隐种,对多国林业生产造成了严重危害。由于桉树枝瘿姬小蜂体型微小,且无法从形态上区分隐种类型,给该害虫的防治造成困难。本研究基于线粒体DNA细胞色素C氧化酶亚基I(mtDNA COI)基因序列的种特异性(species-specific COI,SS-COI)PCR方法,研究桉树枝瘿姬小蜂隐种快速分子检测技术。基于隐种A、B的COI序列分别设计特异性SS-COI引物各1对(AF/AR和BF/BR)。使用这两对引物扩增同一桉树枝瘿姬小蜂样品DNA,即可有效进行隐种鉴定,同时两对引物也能互相验证鉴定结果。引物鉴定灵敏性检测结果显示,AF/AR与BF/BR均具有较高的鉴定灵敏性,其对DNA的有效鉴定浓度阈值分别为11.42 pg/μL和28.32 pg/μL。本研究开发的桉树枝瘿姬小蜂隐种A、B的快速鉴定方法解决了桉树枝瘿姬小蜂入侵地区隐种鉴别的难题,极大缩短鉴定时间、降低鉴定费用,为进一步探究桉树枝瘿姬小蜂隐种A、B的生物学差异以及它们对不同抗性品种桉树的适应能力提供技术参考。 展开更多
关键词 桉树枝瘿姬小蜂 隐种鉴定 种特异性COI引物 快速鉴定 分子检测
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