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期刊论文 54

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关键词

CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

Chrestenson谱 1

ICI）；最大似然估计（maximum likelihood estimation 1

MLE） 1

OFDM）；快速傅立叶变换（Fast Fourier transform， FFT）；循环前缀（cyclic prefix 1

m值逻辑函数 1

严格雪崩准则 1

假单胞菌 1

参数优选 1

吸附 1

周期平稳 1

周期注水 1

周期采油 1

地震波 1

基于质谱的免疫肽组学 1

富含异亮氨酸的延伸蛋白 1

循环双谱 1

循环荷载 1

患者来源肝胆肿瘤类器官 1

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Head-to-tail cyclization of a heptapeptide eliminates its cytotoxicity and significantly increases its inhibition effect on amyloid

Shuai Ma, Huan Zhang, Xiaoyan Dong, Linling Yu, Jie Zheng, Yan Sun

《化学科学与工程前沿（英文）》 2018年 第12卷 第2期   页码 283-295 doi: 10.1007/s11705-017-1687-2

摘要： Amyloid- (A ) protein aggregation is the main hallmark of Alzheimer’s disease (AD). Inhibition of A fibrillation is thus a promising therapeutic approach to the prevention and treatment of AD. Recently, we designed a heptapeptide inhibitor, LVFFARK (LK7). LK7 shows a promising inhibitory capability on A fibrillation, but is prone to self-assembling and displays high cytotoxicity, which would hinder its practical application. Herein, we modified LK7 by a head-to-tail cyclization and obtained a cyclic LK7 (cLK7). cLK7 exhibits a different self-assembly behavior from LK7, and has higher stability against proteolysis than LK7 and little cytotoxicity to SH-SY5Y cells. Thermodynamic analysis revealed that both LK7 and cLK7 could bind to A by electrostatic interactions, hydrogen bonding and hydrophobic interactions, but the binding affinity of cLK7 for A ( = 4.96 µmol/L) is six times higher than that of LK7 ( = 32.2 µmol/L). The strong binding enables cLK7 to stabilize the secondary structure of A and potently inhibit its nucleation, fibrillation and cytotoxicity at extensive concentration range, whereas LK7 could only moderately inhibit A fibrillation and cytotoxicity at low concentrations. The findings indicate that the peptide cyclization is a promising approach to enhance the performance of peptide-based amyloid inhibitors.

关键词： Alzheimer’s disease     amyloid β-protein     cyclic peptide     inhibition     protein aggregation    

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Atomistic characterization of binding modes and affinity of peptide inhibitors to amyloid-

Fufeng LIU,Wenjie DU,Yan SUN,Jie ZHENG,Xiaoyan DONG

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 433-444 doi: 10.1007/s11705-014-1454-6

摘要： The aggregation of amyloid -protein (A ) is tightly linked to the pathogenesis of Alzheimer’s disease. Previous studies have found that three peptide inhibitors (i.e., KLVFF, VVIA, and LPFFD) can inhibit A aggregation and alleviate A -induced neurotoxicity. However, atomic details of binding modes and binding affinities between these peptide inhibitors and A have not been revealed. Here, using molecular dynamics simulations and molecular mechanics Poisson Boltzmann surface area (MM/PBSA) analysis, we examined the effect of three peptide inhibitors (KLVFF, VVIA, and LPFFD) on their sequence-specific interactions with A and the molecular basis of their inhibition. All inhibitors exhibit varied binding affinity to A , in which KLVFF has the highest binding affinity, whereas LPFFD has the least. MM/PBSA analysis further revealed that different peptide inhibitors have different modes of interaction with A , consequently hotspot binding residues, and underlying driving forces. Specific residue-based interactions between inhibitors and A were determined and compared for illustrating different binding and inhibition mechanisms. This work provides structure-based binding information for further modification and optimization of these three peptide inhibitors to enhance their binding and inhibitory abilities against A aggregation.

关键词： Alzheimer’s disease     amyloid β-protein     peptide inhibitors     protein-protein interaction     molecular dynamics simulation    

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Cystine oligomers successfully attached to peptide cysteine-rich fibrils

Christian Bortolini,Mingdong Dong

《化学科学与工程前沿（英文）》 2016年 第10卷 第1期   页码 99-102 doi: 10.1007/s11705-016-1554-6

摘要： Amyloid peptides are renowned to be related to neurodegenerative diseases, however, a fruitful avenue is to employ them as high-performance nanomaterials. These materials benefit from the intrinsic outstanding mechanical robustness of the amyloid backbone made of -strands. In this work, we exploited amyloid-like fibrils as functional material to attach pristine L-cysteine aggregates (cystine oligomers) and gold nanoparticles, without the need of templating compounds. This work will open new avenues on functional materials design and their realisation.

关键词： cysteine     peptide fibrils     gold nanoparticles     amyloids     oligomers     nanomaterials    

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Glucagon-like peptide-2 exhibits protective effect on hepatic ischemia-reperfusion injury in rats

null

《医学前沿（英文）》 2015年 第9卷 第3期   页码 368-373 doi: 10.1007/s11684-015-0403-1

摘要：

Glucagon-like peptide-2 (GLP-2) has potent anti-inflammatory effects and protects against experimental ischemia/reperfusion (I/R) injury in pulmonary, intestinal, and myocardial tissue. However, its protective abilities against I/R injury in the liver are unknown. We investigated the potential role of GLP-2 pretreatment on hepatic I/R injury in rats. A total of 24 rats were randomly divided into three groups (n = 8). The first group was the control group; the second group was the vehicle-treated hepatic ischemia/reperfusion (HIR, vehicle saline-treated) group; and the third group was the GLP-2 pretreated I/R (GLP2-IR) group. Each rat in the third group was intraperitoneally administered 5 μg GLP-2 for 5 d before the procedure. A portal triad was created to induce ischemia with a vascular atraumatic clamp. After 40 min, the clamp was released to initiate hepatic reperfusion for 6 h. Blood samples and tissue specimens from the liver were obtained. Alanine aminotransferase, aspartate aminotransferase, and total bilirubin levels significantly increased in the saline-treated HIR group (P<0.001), whereas GLP-2 pretreatment significantly decreased their levels (P<0.01). Our data suggested that GLP-2 pretreatment may have a protective effect on liver I/R injury. However, dose-response studies are necessary to determine the most effective dose.

关键词： ischemia/reperfusion     liver     glucagon-like peptide-2     alanine aminotransferase    

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The role of natriuretic peptide precursor A gene polymorphism in the development of coronary heart disease

Ripen NSENGA MD, Longxian CHENG PhD, Mei’an HE PhD, Tangchun WU PhD,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 437-442 doi: 10.1007/s11684-009-0074-x

摘要： Natriuretic peptide precursor A (NPPA) is synthesized, stored, and released by atrial myocytes. Previous studies have shown that NPPA plays a significant role in the regulation of coronary circulation and in atherosclerosis. Rs5065 NPPA gene polymorphism leads to the translation of NPPA with two additional arginines and has been suggested to be associated with salt-sensitive hypertension. The purpose of the present study was to investigate the relationship between the rs5065 NPPA gene polymorphism and the risk of coronary heart disease (CHD) in Chinese Han population. We genotyped the single nucleotide polymorphism (SNP) rs5065 NPPA in the human NPPA gene in 1861 sex- and age-matched subjects, comprising of 904 CHD cases and 957 controls of Chinese Han population. Genotyping of SNP was performed with Taqman SNP allelic discrimination assays by means of an ABI 7900HT. Our study showed that the frequencies of rs5065 NPPA C allele in the case and the control groups were 0.012 and 0.005, respectively. There was significant difference in C allele frequency distribution between the two groups (OR=2.607, 95% CI: 1.197−5.678, =0.012). In the case group, there was significant difference between smokers and nonsmokers with subjects carrying C allele (=0.037), and no significant difference in gender, age, fasting total cholesterol (TC), triglycerides (TG), fasting plasma glucose (FPG), body mass index (BMI), and blood pressure (BP) between the cases and the controls (>0.05). Our results suggest that the C allele of rs5065 NPPA gene polymorphism may be associated with the risk of CHD.

关键词： natriuretic peptide precursor A     coronary heart disease     gene polymorphism     allelic discrimination     polymorphism     single nucleotide    

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An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1531-1544 doi: 10.1007/s11709-020-0675-7

摘要： Some of the current concrete damage plasticity models in the literature employ a single damage variable for both the tension and compression regimes, while a few more advanced models employ two damage variables. Models with a single variable have an inherent difficulty in accounting for the damage accrued due to tensile and compressive actions in appropriately different manners, and their mutual dependencies. In the current models that adopt two damage variables, the independence of these damage variables during cyclic loading results in the failure to capture the effects of tensile damage on the compressive behavior of concrete and vice-versa. This study presents a cyclic model established by extending an existing monotonic constitutive model. The model describes the cyclic behavior of concrete under multiaxial loading conditions and considers the influence of tensile/compressive damage on the compressive/tensile response. The proposed model, dubbed the enhanced concrete damage plasticity model (ECDPM), is an extension of an existing model that combines the theories of classical plasticity and continuum damage mechanics. Unlike most prior studies on models in the same category, the performance of the proposed ECDPM is evaluated using experimental data on concrete specimens at the material level obtained under cyclic multiaxial loading conditions including uniaxial tension and confined compression. The performance of the model is observed to be satisfactory. Furthermore, the superiority of ECDPM over three previously proposed constitutive models is demonstrated through comparisons with the results of a uniaxial tension-compression test and a virtual test.

关键词： damage plasticity model     plain concrete     cyclic loading     multiaxial loading conditions    

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Isogeometric analysis of coupled thermo-elastodynamic problems under cyclic thermal shock

Asghar AMANI DASHLEJEH

《结构与土木工程前沿（英文）》 2019年 第13卷 第2期   页码 397-405 doi: 10.1007/s11709-018-0473-7

摘要： The isogeometric analysis (IGA) method was extended for the solution of the coupled thermo-elastodynamic equations. The dimensionless formulation was accepted in discretization of the uncoupled and coupled thermoelasticity equations and the Generalized Newmark method was used in the time integration procedure. First, the performance of the proposed method was verified against a two-dimensional benchmark example subjected to constant thermal shock with available exact analytical solutions. Then a two-dimensional half-space benchmark example under thermal shock was solved. Finally, cyclic thermal shock (CTS) loading was applied on the half-space problem. The results dedicated that IGA can be used as a suitable approach in the analysis of the general thermomechanical problems.

关键词： isogeometric analysis     coupled thermo-elastodynamic     dynamic analysis     generalized newmark     cyclic thermal shock    

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Overcoming oral insulin delivery barriers: application of cell penetrating peptide and silica-based nanoporous

Huining HE, Junxiao YE, Jianyong SHENG, Jianxin WANG, Yongzhuo HUANG, Guanyi CHEN, Jingkang WANG, Victor C YANG

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 9-19 doi: 10.1007/s11705-013-1306-9

摘要： Oral insulin delivery has received the most attention in insulin formulations due to its high patient compliance and, more importantly, to its potential to mimic the physiologic insulin secretion seen in non-diabetic individuals. However, oral insulin delivery has two major limitations: the enzymatic barrier that leads to rapid insulin degradation, and the mucosal barrier that limits insulin’s bioavailability. Several approaches have been actively pursued to circumvent the enzyme barrier, with some of them receiving promising results. Yet, thus far there has been no major success in overcoming the mucosal barrier, which is the main cause in undercutting insulin’s oral bioavailability. In this review of our group’s research, an innovative silica-based, mucoadhesive oral insulin formulation with encapsulated-insulin/cell penetrating peptide (CPP) to overcome both enzyme and mucosal barriers is discussed, and the preliminary and convincing results to confirm the plausibility of this oral insulin delivery system are reviewed. In vitro studies demonstrated that the CPP-insulin conjugates could facilitate cellular uptake of insulin while keeping insulin’s biologic functions intact. It was also confirmed that low molecular weight protamine (LMWP) behaves like a CPP peptide, with a cell translocation potency equivalent to that of the widely studied TAT. The mucoadhesive properties of the produced silica-chitosan composites could be controlled by varying both the pH and composition; the composite consisting of chitosan (25 wt-%) and silica (75 wt-%) exhibited the greatest mucoadhesion at gastric pH. Furthermore, drug release from the composite network could also be regulated by altering the chitosan content. Overall, the universal applicability of those technologies could lead to development of a generic platform for oral delivery of many other bioactive compounds, especially for peptide or protein drugs which inevitably encounter the poor bioavailability issues.

关键词： insulin     cell penetrating peptide     mucoadhesive composites     oral delivery    

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Prediction of cyclic large plasticity for prestrained structural steel using only tensile coupon tests

Liang-Jiu JIA, Tsuyoshi KOYAMA, Hitoshi KUWAMURA

《结构与土木工程前沿（英文）》 2013年 第7卷 第4期   页码 466-476 doi: 10.1007/s11709-013-0219-5

摘要： Cold-formed steel members, which experience complicated prestrain histories, are frequently applied in structural engineering. This paper aims to predict cyclic plasticity of structural steels with tensile and compressive prestrain. Monotonic and cyclic tests on hourglass specimens with tensile and compressive prestrain are conducted, and compared with numerical simulations using the Chaboche model. Two approaches are taken in the simulation. The first requires only the monotonic tensile test data from the prestrained steels, and the second requires both the monotonic tensile test data from the virgin steel and the prestrain histories. The first approach slightly overestimates the compressive stress for specimens with tensile prestrain, while the second approach is able to accurately predict the cyclic plasticity in specimens with tensile and compressive prestrain.

关键词： cyclic plasticity     prestrain     Chaboche model     mild steel    

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循环双谱及在周期平稳类故障中的应用

苏中元,贾民平,许飞云,胡建中

《中国工程科学》 2006年 第8卷 第9期   页码 57-60

摘要：

论述了未知循环频率的周期平稳信号循环双谱的估计方法；研究了在循环双谱的循环累积量计算中涉及变量的简化存储方法，提出了该变量矩阵是对称阵，通过算法可以三角阵的元素来表述，克服了循环双谱传统估计方法计算量较大的缺陷，提高了运算效率；提出了循环双谱对调相故障信号的分析能力，以及对加性噪声的处理能力，仿真并验证了该方法的有效性，并将其应用于旋转机械状态分析。

关键词： 周期平稳     循环双谱     滞后积    

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Rational Design of and Mechanism Insight into an Efficient Antifreeze Peptide for Cryopreservation

Haishan Qi,Yihang Gao,Lin Zhang,Zhongxin Cui,Xiaojie Sui,Jianfan Ma,Jing Yang,Zhiquan Shu,Lei Zhang,

《工程（英文）》 doi: 10.1016/j.eng.2023.01.015

摘要： The development of effective antifreeze peptides to control ice growth has attracted a significant amount of attention yet still remains a great challenge. Here, we propose a novel design method based on an in-depth investigation of repetitive motifs in various ice-binding proteins (IBPs) with an evolution analysis. In this way, several peptides with notable antifreeze activity were developed. In particular, a designed antifreeze peptide named AVD exhibits ideal ice recrystallization inhibition (IRI), solubility, and biocompatibility, making it suitable for use as a cryoprotective agent (CPA). A mutation analysis and molecular dynamics (MD) simulations indicated that the Thr6 and Asn8 residues of the AVD peptide are fundamental to its ice-binding capacity, while the Ser18 residue can synergistically enhance their interaction with ice, revealing the antifreeze mechanism of AVD. Furthermore, to demonstrate the cryoprotection potential of AVD, the peptide was successfully employed for the cryopreservation of various cells, which demonstrated significant post-freezing cell recovery. This work opens up a new avenue for designing antifreeze materials and provides peptide-based functional modules for synthetic biology.

关键词： Antifreeze peptides     Evolution analysis     Ice recrystallization inhibition     Molecular dynamics simulation     Cryopreservation     Synthetic biology    

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电中性固体表面上多条肽链的吸附过程——粗粒化模拟研究 Research

裘若桑, 肖杰, 陈晓东

《工程（英文）》 2020年 第6卷 第2期   页码 185-194 doi: 10.1016/j.eng.2018.12.012

摘要：

蛋白质在固体表面的吸附过程涉及诸多复杂的分子间相互作用，因此到目前为止仍然无法做到精准调控。通过模拟计算，可以获取固-液界面分子尺度的蛋白质移动机理，从而为预测蛋白质吸附和结垢现象提供可靠的理论依据。本研究通过多尺度粗粒化模型对多条疏水的丙氨酸十二肽在金表面的聚集和吸附过程进行了分析。大约有一半（46.6%）的丙氨酸十二肽可以组成聚集体。30.0%的独立肽链会被快速地吸附到固体表面。这些在表面吸附的肽链经过一段时间的爬行，其中的一些（51.0%）能与吸附在表面的或是游离在溶液中的肽链融合，从而形成吸附在表面的聚集体。这些在固-液界面吸附的肽链使得固体表面性质发生变化。这一变化可能会进一步影响之后溶液中肽链和聚集体在金表面的吸附。本研究揭示的多条肽链吸附机理有希望为进一步研究多个蛋白质分子在固体表面的吸附机理提供理论基础。

关键词： 肽链     聚集体     吸附     粗粒化计算    

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Experimental research on seismic behavior of recycled concrete frame under varying cyclic loading

SUN Yuedong, XIAO Jianzhuang, ZHOU Deyuan

《结构与土木工程前沿（英文）》 2008年 第2卷 第4期   页码 302-308 doi: 10.1007/s11709-008-0050-6

摘要： A study is conducted on the seismic behavior of one natural concrete frame and two recycled concrete frames with 100% recycled coarse aggregate whose scales are 1:2 entirely, and a comparative study is conducted under low-reversed cyclic lateral loading and different vertical loading. This work aims to estimate the failure mechanism, hysteresis loops, displacement ductility, deterioration of strength and stiffness and energy dissipation of recycled concrete frames under low-reversed cyclic loading as well as the influence of different vertical loading. Analysis on the basis of the experiment proves that it is entirely feasible to apply recycled concrete to practical engineering for the sake of its good seismic behaviors. Theoretical base is provided for further study and practical application of recycled concrete structure.

关键词： different     aggregate     stiffness     practical application     % recycled    

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Cyclic behavior of prefabricated reinforced concrete frame with infill slit shear walls

Kui XIAO,Qilin ZHANG,Bin JIA

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 63-71 doi: 10.1007/s11709-015-0294-x

摘要： A composite structural system consisting of prefabricated reinforced concrete frame with infill slit shear walls (PRCFW), with good ductility, is a new type of earthquake resistant structure. Pseudo-static tests were performed to evaluate the seismic behavior of the PRCFW system. Two one-bay, two-story PRCFW specimens were both built at one-half scale. Additional computational research is also conducted to enhance the nonlinear analytical capabilities for this system. Combined with the concrete damaged plastic (CDP) model provided by finite element program ABAQUS and the constitutive model of concrete proposed by Chinese code, the damage process of the PRCFW structure under cyclic load is simulated. The simulated results show a good agreement with the test data, the dynamic behavior of the PRCFW system can be simulated sufficiently accurate and efficient to provide useful design information. The experimental and numerical study show that this system has the potential to offer good ductility and energy absorption capacity to dissipate input energy, and stiffness adequate for controlling drift for buildings located in earthquake-prone regions.

关键词： slit shear wall     constitutive model     cyclic     seismic     damage    

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特高含水期分层段周期注采技术研究与实践认识

姜振海

《中国工程科学》 2012年 第14卷 第4期   页码 77-82

摘要：

针对萨北开发区油层沉积特点及特高含水期剩余油分布特点，以水动力学原理为指导，在已有周期注水实践经验的基础上，结合数值模拟进行机理研究，优化周期注采方式及各项参数，引入了分层段交叉注采改变液流方向改善开发效果的做法，在实践中取得了较好的效果。

关键词： 周期注水     周期采油     方式优化     参数优选    

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标题 作者 时间 类型 操作

Head-to-tail cyclization of a heptapeptide eliminates its cytotoxicity and significantly increases its inhibition effect on amyloid

Shuai Ma, Huan Zhang, Xiaoyan Dong, Linling Yu, Jie Zheng, Yan Sun

期刊论文

Atomistic characterization of binding modes and affinity of peptide inhibitors to amyloid-

Fufeng LIU,Wenjie DU,Yan SUN,Jie ZHENG,Xiaoyan DONG

期刊论文

Cystine oligomers successfully attached to peptide cysteine-rich fibrils

Christian Bortolini,Mingdong Dong

期刊论文

Glucagon-like peptide-2 exhibits protective effect on hepatic ischemia-reperfusion injury in rats

null

期刊论文

The role of natriuretic peptide precursor A gene polymorphism in the development of coronary heart disease

Ripen NSENGA MD, Longxian CHENG PhD, Mei’an HE PhD, Tangchun WU PhD,

期刊论文

An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

期刊论文

Isogeometric analysis of coupled thermo-elastodynamic problems under cyclic thermal shock

Asghar AMANI DASHLEJEH

期刊论文

Overcoming oral insulin delivery barriers: application of cell penetrating peptide and silica-based nanoporous

Huining HE, Junxiao YE, Jianyong SHENG, Jianxin WANG, Yongzhuo HUANG, Guanyi CHEN, Jingkang WANG, Victor C YANG

期刊论文

Prediction of cyclic large plasticity for prestrained structural steel using only tensile coupon tests

Liang-Jiu JIA, Tsuyoshi KOYAMA, Hitoshi KUWAMURA

期刊论文

循环双谱及在周期平稳类故障中的应用

苏中元,贾民平,许飞云,胡建中

期刊论文

Rational Design of and Mechanism Insight into an Efficient Antifreeze Peptide for Cryopreservation

Haishan Qi,Yihang Gao,Lin Zhang,Zhongxin Cui,Xiaojie Sui,Jianfan Ma,Jing Yang,Zhiquan Shu,Lei Zhang,

期刊论文

电中性固体表面上多条肽链的吸附过程——粗粒化模拟研究

裘若桑, 肖杰, 陈晓东

期刊论文

Experimental research on seismic behavior of recycled concrete frame under varying cyclic loading

SUN Yuedong, XIAO Jianzhuang, ZHOU Deyuan

期刊论文

Cyclic behavior of prefabricated reinforced concrete frame with infill slit shear walls

Kui XIAO,Qilin ZHANG,Bin JIA

期刊论文

特高含水期分层段周期注采技术研究与实践认识

姜振海

期刊论文