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Observation on the Efficacy of One-Knot-Two-Wire Suture Bridge Method Technique in Treating Small and Medium-Sized Rotator Cuff Tears
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作者 Chaoqi Pang Songlin Liu Liang Ma 《Open Journal of Orthopedics》 2024年第12期562-570,共9页
Objective: To explore the clinical efficacy of shoulder arthroscopic one-knot-two-wire suture bridge technique in the treatment of small and medium-sized rotator cuff tears. Methods: The clinical data of 22 patients w... Objective: To explore the clinical efficacy of shoulder arthroscopic one-knot-two-wire suture bridge technique in the treatment of small and medium-sized rotator cuff tears. Methods: The clinical data of 22 patients with small and medium-sized rotator cuff injuries treated with the one-knot-two-wire suture bridge technique from February 2022 to June 2023 in the Department of Orthopaedics of Jingzhou Hospital Affiliated to Yangtze University were retrospectively analysed, among which 14 cases were male and 8 cases were female;the age ranged from 35 to 68 years old, with an average of (50.86 ± 10.80) years old. All cases underwent an MRI examination of the shoulder joint to understand the type and degree of injury. The duration of the disease ranged from 120 to 166 d, with a mean of (141.23 ± 13.46) d. The evaluation of the operation time, intraoperative bleeding, visual analogue scale (VAS) of pain, Constant-Murley score and Sugaya grading of shoulder MRI were performed at the last follow-up. Results: All 22 patients were followed up for 12 - 18 months, with a mean of (14.68 ± 1.89 d). The operation time was 38 - 58 min, mean (48.18 ± 5.92) min;intraoperative bleeding was 5 - 15 mL, mean (10.00 ± 3.45) mL. All patients achieved normal healing without re-tear, vascular and nerve injury, incision infection, anchor nail loosening and dislodgement and other complications. At the last follow-up, both shoulders were normal in shape and symmetrical on both sides. The VAS score was 0 - 1.2 points, with an average of 0.61 ± 0.42 points, and the Constant-Murley score was 70 - 98 points, with an average of 86.09 ± 8.56 points. The Sugaya classification of MRI examination was 17 cases of grade I, 4 cases of grade II, and 1 case of grade III. Conclusion: One-knot-two-wire suture bridge technique is used for the treatment of small and medium-sized rotator cuff tears with short operative time, low bleeding, and good clinical outcome. 展开更多
关键词 One-Knot-two-Wire Bridge Method Rotator Cuff Tear Shoulder Arthroscopy Suture Bridge
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“N-Two-N”教学模式的构建及在本科有机化学教学中的探究实践 被引量:1
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作者 李万梅 欧阳娅妮 章鹏飞 《大学化学》 CAS 2023年第11期54-63,共10页
基于立德树人的核心目标,探索了本科有机化学教学的新思路,从提高教师引导作用、提升学生自主学习能力、优化评价考核方式等方面进行了探索与研究。本研究以CDIO-BOPPPS协同教学模式为指导思想,引入CDIO理念创新教学设计构思,借鉴BOPPP... 基于立德树人的核心目标,探索了本科有机化学教学的新思路,从提高教师引导作用、提升学生自主学习能力、优化评价考核方式等方面进行了探索与研究。本研究以CDIO-BOPPPS协同教学模式为指导思想,引入CDIO理念创新教学设计构思,借鉴BOPPPS模式改革教学过程,结合多种教学法和多种评价方式,构建一个“N-Two-N”一体化的课堂教学体系。本文阐述了“N-Two-N”一体化模式的落实过程以及该教学模式的优点和取得的成效。 展开更多
关键词 “N-two-N”模式 CDIO-BOPPPS协同教学 立德树人 教学方法 有机化学
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Numerical Simulation for Two-Phase Water Hammer Flows in Pipe by Quasi-Two-Dimensional Model 被引量:2
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作者 Tae Uk Jang Yuebin Wu +1 位作者 Ying Xu Qiang Sun 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第2期9-15,共7页
The features of a quasi-two-dimensional( quasi-2D) model for simulating two-phase water hammer flows with vaporous cavity in a pipe are investigated. The quasi-2D model with discrete vaporous cavity in the pipe is pro... The features of a quasi-two-dimensional( quasi-2D) model for simulating two-phase water hammer flows with vaporous cavity in a pipe are investigated. The quasi-2D model with discrete vaporous cavity in the pipe is proposed in this paper. This model uses the quasi-2D model for pure liquid zone and one-dimensional( 1D) discrete vapor cavity model for vaporous cavity zone. The quasi-2D model solves two-dimensional equations for both axial and radial velocities and 1D equations for both pressure head and discharge by the method of characteristics. The 1D discrete vapor cavity model is used to simulate the vaporous cavity occurred when the pressure in the local pipe is lower than the vapor pressure of the liquid. The proposed model is used to simulate two-phase water flows caused by the rapid downstream valve closure in a reservoir-pipe-valve system.The results obtained by the proposed model are compared with those by the corresponding 1D model and the experimental ones provided by the literature,respectively. The comparison shows that the maximum pressure heads simulated by the proposed model are more accurate than those by the corresponding 1D model. 展开更多
关键词 water HAMMER method of characteristics QUASI -two -dimensional MODEL COLUMN separation discrete vapor cavity MODEL
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Construction and Analysis of Structured Preconditioners for Block Two-by-Two Matrices 被引量:8
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作者 白中治 《Journal of Shanghai University(English Edition)》 CAS 2004年第4期397-405,共9页
For the large sparse block two-by-two real nonsingular matrices, we establish a general framework of structured preconditioners through matrix transformation and matrix approximations. For the specific versions such a... For the large sparse block two-by-two real nonsingular matrices, we establish a general framework of structured preconditioners through matrix transformation and matrix approximations. For the specific versions such as modified block Jacobi-type, modified block Gauss-Seidel-type, and modified block unsymmetric (symmetric) Gauss-Seidel-type preconditioners, we precisely describe their concrete expressions and deliberately analyze eigenvalue distributions and positive definiteness of the preconditioned matrices. Also, we show that when these structured preconditioners are employed to precondition the Krylov subspace methods such as GMRES and restarted GMRES, fast and effective iteration solvers can be obtained for the large sparse systems of linear equations with block two-by-two coefficient matrices. In particular, these structured preconditioners can lead to high-quality preconditioning matrices for some typical matrices from the real-world applications. 展开更多
关键词 block two-by-two matrix PRECONDITIONER modified block relaxation iteration eigenvalue distribution positive definiteness.
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基于密度估计和VGG-Two的大豆籽粒快速计数方法 被引量:1
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作者 王莹 李越 +2 位作者 武婷婷 孙石 王敏娟 《智慧农业(中英文)》 2021年第4期111-122,共12页
为快速准确计数大豆籽粒,提高大豆考种速度和育种水平,本研究提出了一种基于密度估计和VGG-Two(VGG-T)的大豆籽粒计数方法。首先针对大豆籽粒计数领域可用图像数据集缺乏的问题,提出了基于数字图像处理技术的预标注和人工修正标注相结... 为快速准确计数大豆籽粒,提高大豆考种速度和育种水平,本研究提出了一种基于密度估计和VGG-Two(VGG-T)的大豆籽粒计数方法。首先针对大豆籽粒计数领域可用图像数据集缺乏的问题,提出了基于数字图像处理技术的预标注和人工修正标注相结合的快速目标点标注方法,加快建立带标注的公开可用大豆籽粒图像数据集。其次构建了适用于籽粒图像数据集的VGG-T网络计数模型,该模型基于VGG16,结合密度估计方法,实现从单一视角大豆籽粒图像中准确计数籽粒。最后采用自制的大豆籽粒数据集对VGG-T模型进行测试,分别对有无数据增强的计数准确性、不同网络的计数性能以及不同测试集的计数准确性进行了对比试验。试验结果表明,快速目标点标注方法标注37,563个大豆籽粒只需花费197 min,比普通人工标注节约了1592 min,减少约96%的人工工作量,大幅降低时间成本和人工成本;采用VGG-T模型计数,其评估指标在原图和补丁(patch)情况下的平均绝对误差分别为0.6和0.2,均方误差为0.6和0.3,准确性高于传统图像形态学操作以及ResNet18、ResNet18-T和VGG16网络。在包含不同密度大豆籽粒的测试集中,误差波动较小,仍具有优良的计数性能,同时与人工计数和数粒仪相比,计数11,350个大豆籽粒分别节省大约2.493 h和0.203 h,实现大豆籽粒的快速计数任务。 展开更多
关键词 卷积神经网络 籽粒计数 籽粒图像 点标注 密度图 VGG-two 育种
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临床废弃机用M-two镍钛锉的损伤分析 被引量:4
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作者 张平虎 屈铁军 倪龙兴 《牙体牙髓牙周病学杂志》 CAS 2016年第3期175-179,共5页
目的:探讨M-two镍钛锉在根管治疗中的损伤、断裂机制。方法:从临床收集近6个月内906支废弃的机用M-two镍钛锉,体视显微镜观察损伤情况,并且对断锉进行微距数码摄影,同时运用ImagePro Plus软件对断点位置进行测量。采用SPSS 17.0软件包... 目的:探讨M-two镍钛锉在根管治疗中的损伤、断裂机制。方法:从临床收集近6个月内906支废弃的机用M-two镍钛锉,体视显微镜观察损伤情况,并且对断锉进行微距数码摄影,同时运用ImagePro Plus软件对断点位置进行测量。采用SPSS 17.0软件包对数据进行统计学分析。结果:906支M-two镍钛锉中,有196支锉刃发生塑性形变(21.6%);221支锉发生断裂(24.4%)。#10.04锉器械分离率最高(39.3%),#15.05次之(33.6%)。#30.05锉的断裂位点最高(3.65±0.80)mm。折断的类型主要包括:弯曲疲劳折断(65.2%)和扭转折断(34.8%)。结论:#10.04和#15.05锉塑性形变占有较高比例,因此建议一次性使用;其余锉建议临床降低使用次数,并且定期更换。 展开更多
关键词 器械分离 M-two镍钛锉 疲劳失效
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Screening of hepatocyte proteins binding to NS5ABP37 protein by yeast-two hybrid system 被引量:1
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作者 Lei Zhang1,Qing-yong Ma1,Xian-kui Meng1,Kang Li1,Jun Cheng21.The First Affiliated Hospital,Medical School of Xi’an Jiaotong University,Xi’an 710061 2.Institute of Infectious Diseases,Beijing Ditan Hospital,Beijing 100011,China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2009年第4期234-237,251,共5页
Objective To investigate the biological function of NS5ABP37 and to look for proteins interacting with NS5ABP37 protein in hepatocytes.Methods We constructed bait plasmid expressing NS5ABP37 protein of hepatitis C vir... Objective To investigate the biological function of NS5ABP37 and to look for proteins interacting with NS5ABP37 protein in hepatocytes.Methods We constructed bait plasmid expressing NS5ABP37 protein of hepatitis C virus(HCV)by cloning the gene of NS5ABP37 protein into pGBKT7,then the recombinant plasmid DNA was transformed into yeast AH109(α type).The transformed yeast AH109 was mated with yeast Y187(α type)containing liver cDNA library plasmid in 2×YPDA medium.Diploid yeast was plated on synthetic dropout nutrient medium(SD/-Trp-Leu-His-Ade)containing X-α-gal for selection and screening.After extracting and sequencing of plasmids from positive(blue)colonies,we made a sequence analysis by bioinformatics.Results We screened twenty-five proteins binding to NS5ABP37,including Homo sapiens cyclin I(CCNI)gene,Homo sapiens matrix metallopeptidase 25(MMP25)and Homo sapiens talin 1.Conclusion The yeast-two hybrid system is an effective method for identifying hepatocyte proteins interacting with NS5ABP37 of HCV.And the biological function of NS5ABP37 may be associated with glycometabolism,lipid metabolism and apoptosis. 展开更多
关键词 NS5ABP37 yeast-two hybrid system hepatitis C virus(HCV)
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Codimension-two bifurcation of axial loaded beam bridge subjected to an infinite series of moving loads 被引量:1
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作者 杨新伟 田瑞兰 李海涛 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期121-126,共6页
A novel model is proposed which comprises of a beam bridge subjected to an axial load and an infinite series of moving loads. The moving loads, whose distance between the neighbouring ones is the length of the beam br... A novel model is proposed which comprises of a beam bridge subjected to an axial load and an infinite series of moving loads. The moving loads, whose distance between the neighbouring ones is the length of the beam bridge, coupled with the axial force can lead the vibration of the beam bridge to codimension-two bifurcation. Of particular concern is a parameter regime where non-persistence set regions undergo a transition to persistence regions. The boundary of each stripe represents a bifurcation which can drive the system off a kind of dynamics and jump to another one, causing damage due to the resulting amplitude jumps. The Galerkin method, averaging method, invertible linear transformation, and near identity nonlinear transformations are used to obtain the universal unfolding for the codimension-two bifurcation of the mid-span deflection. The efficiency of the theoretical analysis obtained in this paper is verified via numerical simulations. 展开更多
关键词 mid-span deflection beam bridge infinite series of moving loads codimension-two bifurcation
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The Influence Function of the Correlation Indexes in a Two-by-Two Table
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作者 Giovanni Girone Fabio Manca Claudia Marin 《Applied Mathematics》 2014年第21期3411-3420,共10页
In this paper we examine 5 indexes (the two Yule’s indexes, the chi square, the odds ratio and an elementary index) of a two-by-two table, which estimate the correlation coefficient ρ in a bivariate Bernoulli distri... In this paper we examine 5 indexes (the two Yule’s indexes, the chi square, the odds ratio and an elementary index) of a two-by-two table, which estimate the correlation coefficient ρ in a bivariate Bernoulli distribution. We will find the compact expression of the influence functions, which allow the quantification of the effect of an infinitesimal contamination of the probability of any pair of attributes of the bivariate random variable distributed according to the above-mentioned model. We prove that the only unbiased index is the chi square. In order to determine the indexes, which are less sensitive to contamination, we obtain the expressions of three synthetic measures of the influence function, which are the maximum contamination (gross sensitivity error), the mean square deviation and the variance. These results, even if don’t allow a definitive assessment of the overall optimum properties of the five indexes, as not all of them are unbiased, nevertheless they allow to appreciating the synthetic entity of the effect of the contaminations in the estimation of the parameter ρ of the bivariate Bernoulli distribution. 展开更多
关键词 Two-by-two TABLE Influence FUNCTION Correlation Indexes GROSS Sensitivity Error Mean Square Deviation Asymptotic Variance
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Suboptimal stochastic H-two/H-infinity design with spectrum constraint
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作者 Zhongwei LIN Weihai ZHANG Yan LIN 《控制理论与应用(英文版)》 EI 2008年第3期317-321,共5页
This paper studies the problem of suboptimal state-feedback H-two/H-infinity control of stochastic systems with spectrum constraint. Concretely speaking, a mixed suboptimal H-two/H-infinity controller synthesis togeth... This paper studies the problem of suboptimal state-feedback H-two/H-infinity control of stochastic systems with spectrum constraint. Concretely speaking, a mixed suboptimal H-two/H-infinity controller synthesis together with placing the spectrum into a strip region is considered, which is achieved via solving a convex optimization problem. 展开更多
关键词 Stochastic stabilization Suboptimal H-two/H-infinity control Spectrum assignment Linear matrix inequality (LMI)
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Properties of ground state and anomalous quantum fluctuations in one-dimensional polaron-soliton systems-the effects of electron-two-phonon interaction and non-adiabatic quantum correlations
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作者 罗质华 曹锡金 余超凡 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期372-383,共12页
Based on the Holstein model Hamiltonian of one-dimensional molecular crystals, by making use of the expansion approach of the correlated squeezed-coherent states of phonon instead of the two-phonon coherent state expa... Based on the Holstein model Hamiltonian of one-dimensional molecular crystals, by making use of the expansion approach of the correlated squeezed-coherent states of phonon instead of the two-phonon coherent state expansion scheme, the properties of the ground state and the anomalous quantum fluctuations are investigated in a strongly coupled electron-phonon system with special consideration of the electron-two-phonon interaction. The effective renormalization (ai) of the displacement of the squeezed phonons with the effect of the squeezed-coherent states of phonon and both the electron-displaced pbonon and the polaron-squeezed phonon correlations have been combined to obtain the anomalous quantum fluctuations for the corrections of the coherent state. Due to these non-adiabatic correlations, the effective displacement parameter ai is larger than the ordinary parameter ai (0) In comparison with the electron-one-phonon interaction (g) corrected as oig, we have found the electron-two-phonon interaction (gl) corrected as ai2gi is enhanced significantly. For this reason, the ground state energy (E(2)) contributed by the electron-two-phonon interaction is more negative than the single-phonon case (E01)) and the soliton solution is more stable. At the same time, the effects of the electron-two-phonon interaction greatly increase the polaron energy and the quantum fluctuations. Furthermore, in a deeper level, we have considered the effect of the polaron-squeezed phonon correlation (f-correlation). Since this correlation parameter f 〉 1, this effect will strengthen the electron-one and two-phonon interactions by fai9 and f2ai2g1, respectively. The final results show that the ground state energy and the polaron energy will appear more negative further and the quantum fluctuations will gain further improvement. 展开更多
关键词 correlated squeezed-coherent state expansion electron-two-phonon interaction nonadiabatic correlations and renormalized phonon displacement anomalous quantum fluctuations polaron-squeezed phonon correlation
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The Pancharatnam Phase of a Three-Level Atom Coupled to Two Systems of N-Two Level Atoms
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作者 D. A. M. Abo-Kahla 《Journal of Quantum Information Science》 2016年第1期44-55,共12页
In this paper, we present the analytical solution for the model that describes the interaction between a three-level atom and two systems of N-two level atoms. The effects of the quantum numbers and the coupling param... In this paper, we present the analytical solution for the model that describes the interaction between a three-level atom and two systems of N-two level atoms. The effects of the quantum numbers and the coupling parameters between spins on the Pancharatnam phase and the atomic inversion, for some special cases of the initial states, are investigated. The comparison between the two effects shows that the analytic results are well consistent. 展开更多
关键词 Pancharatnam Phase Atomic Inversion Systems of N-two Level Atoms
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Double Fire-Two Stage Method and Parameter Calculation of Underground Coal Gasification
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作者 杨兰和 梁杰 余力 《International Journal of Mining Science and Technology》 SCIE EI 2000年第2期11-14,共4页
The double fire two stage method of underground coal gasification was suggested. On the basis of material balance, the ideal gasification parameters were calculated, and the field test process was briefly introduced. ... The double fire two stage method of underground coal gasification was suggested. On the basis of material balance, the ideal gasification parameters were calculated, and the field test process was briefly introduced. In addition, the cause for a middle to a high heat value of water gas was described. And the reasonableness and feasiblity of the method was proved, showing that the double fire two stage gasification is an important technique for commercialized production. 展开更多
关键词 DOUBLE FIRE sources two STAGE UNDERGROUND COAL GASIFICATION UNDERGROUND water gas
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Photon number cumulant expansion and generating function for photon added-and subtracted-two-mode squeezed states
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作者 卢道明 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期70-73,共4页
For the first time, we derive the photon number cumulant for two-mode squeezed state and show that its cumulant expansion leads to normalization of two-mode photon subtracted-squeezed states and photon added- squeezed... For the first time, we derive the photon number cumulant for two-mode squeezed state and show that its cumulant expansion leads to normalization of two-mode photon subtracted-squeezed states and photon added- squeezed states. We show that the normalization is related to Jacobi polynomial, so the cumulant expansion in turn represents the new generating function of Jacobi polynomial. 展开更多
关键词 Jacobi polynomial photon number cumulant expansion photon subtracted- and photon added- two-mode squeezed states
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Estimation of Area under Receiver Operating Characteristic Curve for Bi-Pareto and Bi-Two Parameter Exponential Models
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作者 Bhavna Kaushal Kanchan Jain Suresh K. Sharma 《Open Journal of Statistics》 2014年第1期1-10,共10页
In this paper, we find the ROC curves for Bi-Pareto and Bi-two parameter exponential distributions. Theoretical, parametric and non-parametric values of area under receiver operating characteristic (AUROC) curve for d... In this paper, we find the ROC curves for Bi-Pareto and Bi-two parameter exponential distributions. Theoretical, parametric and non-parametric values of area under receiver operating characteristic (AUROC) curve for different parametric combinations have been calculated using simulations. These values are compared in terms of root mean square and mean absolute errors. The results are demonstrated for two real data sets. 展开更多
关键词 ROC AUROC PARETO TWO PARAMETER Exponential Root Mean Square ERROR Mean Absolute ERROR
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双组分调控系统对革兰氏阴性菌抗生素耐药性的调控研究进展 被引量:2
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作者 刘欢 刘畅 +3 位作者 雷化雨 曹娟娟 王英英 赵燕妮 《食品与发酵工业》 CAS 北大核心 2025年第1期381-389,共9页
抗生素的滥用导致细菌的耐药性不断增强,其中多重耐药革兰氏阴性菌的检出率不断上升,不仅严重威胁人类健康,还对食品生产和加工环节构成了巨大风险。双组分调控系统(two-component regulatory systems,TCSs)广泛存在于革兰氏阴性菌中,... 抗生素的滥用导致细菌的耐药性不断增强,其中多重耐药革兰氏阴性菌的检出率不断上升,不仅严重威胁人类健康,还对食品生产和加工环节构成了巨大风险。双组分调控系统(two-component regulatory systems,TCSs)广泛存在于革兰氏阴性菌中,由感受信号的组氨酸激酶和相应的响应调节蛋白组成,是细菌体内重要的信号转导系统,广泛参与细菌不同生理进程,并对细菌耐药性具有重要调控作用,因此,针对TCSs的靶向干预被视为潜在的抗耐药策略。该综述从TCSs及其在革兰氏阴性菌不同抗生素耐药性机制中的调控作用(调控抗生素灭活酶合成,调控细胞表面的修饰,药物流入或流出调节和其他调控机制)出发,阐述TCSs在革兰氏阴性菌对抗生素耐药性的调控作用研究进展,旨在为预防和控制食源性耐药病原菌提供理论依据和参考。 展开更多
关键词 双组分调控系统 革兰氏阴性菌 耐药性 抗生素 机制
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超启发蚁群优化算法求解带柔性时间窗的绿色两级多周期车辆路径问题 被引量:2
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作者 郭宁 钱斌 +3 位作者 申秋义 那靖 胡蓉 耿言 《控制与决策》 北大核心 2025年第3期745-754,共10页
针对带柔性时间窗的绿色两级多周期车辆路径问题(G2E-MPVRPFTW),建立同时以最小化碳排放量和最大化客户满意度为目标的数学模型,提出一种结合K-means带时间窗聚类(KCTW)的超启发蚁群优化算法(HHACOA)进行求解.首先,根据G2E-MPVRPFTW大... 针对带柔性时间窗的绿色两级多周期车辆路径问题(G2E-MPVRPFTW),建立同时以最小化碳排放量和最大化客户满意度为目标的数学模型,提出一种结合K-means带时间窗聚类(KCTW)的超启发蚁群优化算法(HHACOA)进行求解.首先,根据G2E-MPVRPFTW大规模、多约束、强耦合的复杂特性,采用KCTW将该问题分解为多个子问题,以降低问题的求解复杂度;其次,使用HHACOA求解分解后的各子问题,并将这些子问题的解合并获得原问题G2E-MPVRPFTW的解.HHACOA在高层策略域生成9种邻域操作的不同排列,采用蚁群优化算法(ACOA)对优质排列信息进行学习,并基于重构的转移概率矩阵生成新的排列,以有效引导搜索到达优质解集中的区域;HHACOA在低层问题域利用启发式规则和随机方法生成初始种群,并将高层产生的每个排列作为一种算法,作用于种群中的每个个体,以实现在解空间更多不同区域进行搜索. 展开更多
关键词 两级车辆路径问题 多周期 绿色 柔性时间窗 多目标优化 超启发蚁群优化算法
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我国“双一流”建设高校高层次人才政策研究 被引量:7
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作者 陈英杰 孙东东 《高校教育管理》 北大核心 2025年第1期36-48,共13页
本研究抽样选取我国4个地区17所“双一流”建设高校高层次人才政策文本,构建“政策工具政策内容要素”二维分析框架,探讨高层次人才政策工具和政策内容要素的组合方式与地区差异。研究发现,我国“双一流”建设高校高层次人才政策的环境... 本研究抽样选取我国4个地区17所“双一流”建设高校高层次人才政策文本,构建“政策工具政策内容要素”二维分析框架,探讨高层次人才政策工具和政策内容要素的组合方式与地区差异。研究发现,我国“双一流”建设高校高层次人才政策的环境型政策工具使用不足,尤其是西部高校的环境型政策工具亟待加强;需求型政策工具中教师培育政策子工具使用不足;南部、西部和北部地区高校对人才培养政策的关注度不够。我国“双一流”建设高校在制定高层次人才政策时,应适度增强环境型政策工具的运用,进一步完善和充实教师培育相关政策;西部地区高校应改善办公实验条件,提高团队建设水平;南部、西部和北部高校应加快制定人才培养相关政策。 展开更多
关键词 “双一流”建设高校 高层次人才 政策文本分析 政策工具 政策内容要素 二维分析框架
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计及㶲效率和多重不确定性的区域综合能源系统双层优化 被引量:2
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作者 鲁玲 苑涛 +4 位作者 杨波 李欣 鲁洋 蒲秋平 张鑫 《中国电力》 北大核心 2025年第1期128-140,共13页
为实现能量高质量、高效率的利用,同时提高系统供能可靠性,针对含高比例的可再生能源的区域综合能源系统,引入“㶲”的概念,提出了一种计及㶲效率和多重不确定性的双层优化方法。首先,建立了区域综合能源系统的多能耦合模型,进行㶲分析和... 为实现能量高质量、高效率的利用,同时提高系统供能可靠性,针对含高比例的可再生能源的区域综合能源系统,引入“㶲”的概念,提出了一种计及㶲效率和多重不确定性的双层优化方法。首先,建立了区域综合能源系统的多能耦合模型,进行㶲分析和多重不确定性分析,并且针对风光不确定性、负荷和能源价格波动的不同特点,分别采取多场景随机规划和区间优化的方法进行处理。然后,建立了上层以㶲效率和经济性为优化目标,下层以运行成本最低为优化目标,兼顾系统容量规划和调度运行的双层协同优化模型。最后,选取某园区进行算例分析,验证了所提方法的有效性,与其他不确定因素相比,电负荷的波动对系统的经济和㶲效率影响更大。 展开更多
关键词 区域综合能源系统 可再生能源 㶲效率 多重不确定性 双层优化
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细颗粒运移与孔隙堵塞对两相渗流特性的影响 被引量:2
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作者 吴婷 杨志兵 +1 位作者 胡冉 陈益峰 《岩土力学》 北大核心 2025年第6期1755-1764,1776,共11页
细颗粒运移广泛存在于自然界与工程领域的两相流动过程中,如污染物运移与修复、油气开采等。然而,颗粒引起的孔隙堵塞对两相渗流特性的影响尚不清楚。基于自主研发的多相渗流三维可视化试验平台,在多孔介质模型中开展了不同流量和孔隙... 细颗粒运移广泛存在于自然界与工程领域的两相流动过程中,如污染物运移与修复、油气开采等。然而,颗粒引起的孔隙堵塞对两相渗流特性的影响尚不清楚。基于自主研发的多相渗流三维可视化试验平台,在多孔介质模型中开展了不同流量和孔隙尺寸条件下的两相驱替试验,深入探讨了细颗粒在多孔介质中的运移和堵塞行为及其对两相流动过程的影响。试验结果表明:细颗粒诱导的多孔介质堵塞过程受流量和孔隙尺寸的协同控制,低流量条件下,孔隙尺寸对堵塞的影响可以忽略,而高流量条件下,孔隙尺寸是决定堵塞的主导因素。通过空间团簇体分析,阐明了孔隙堵塞现象与流体连通特性之间的关系,即堵塞越显著,残余湿润相分布越离散,流体连通性越差。此外,试验还揭示了两相流动过程中堵塞对驱替压力以及驱替效率的调控机制,研究成果有望为优化两相流动过程、提高能源开采效率提供重要的理论依据与实践指导。 展开更多
关键词 多孔介质 细颗粒 孔隙堵塞 两相流 连通特性
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