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Intracellular and extracellular TGF-β signaling in cancer: some recent topics

null

《医学前沿(英文)》 2018年 第12卷 第4期   页码 387-411 doi: 10.1007/s11684-018-0646-8

摘要:

Transforming growth factor (TGF)-β regulates a wide variety of cellular responses, including cell growth arrest, apoptosis, cell differentiation, motility, invasion, extracellular matrix production, tissue fibrosis, angiogenesis, and immune function. Although tumor-suppressive roles of TGF-β have been extensively studied and well-characterized in many cancers, especially at early stages, accumulating evidence has revealed the critical roles of TGF-β as a pro-tumorigenic factor in various types of cancer. This review will focus on recent findings regarding epithelial-mesenchymal transition (EMT) induced by TGF-β, in relation to crosstalk with some other signaling pathways, and the roles of TGF-β in lung and pancreatic cancers, in which TGF-β has been shown to be involved in cancer progression. Recent findings also strongly suggested that targeting TGF-β signaling using specific inhibitors may be useful for the treatment of some cancers. TGF-β plays a pivotal role in the differentiation and function of regulatory T cells (Tregs). TGF-β is produced as latent high molecular weight complexes, and the latent TGF-β complex expressed on the surface of Tregs contains glycoprotein A repetitions predominant (GARP, also known as leucine-rich repeat containing 32 or LRRC32). Inhibition of the TGF-β activities through regulation of the latent TGF-β complex activation will be discussed.

关键词: TGF-β     EMT     lung cancer     pancreatic cancer     latent form     immune function     GARP    

Encapsulation of polyethylene glycol in cellulose-based porous capsules for latent heat storage and light-to-thermal

《化学科学与工程前沿(英文)》 2023年 第17卷 第8期   页码 1038-1050 doi: 10.1007/s11705-022-2279-3

摘要: Phase change materials are potential candidates for the application of latent heat storage. Herein, we fabricated porous capsules as shape-stable materials from cellulose-based polyelectrolyte complex, which were first prepared using cellulose 6-(N-pyridinium)hexanoyl ester as the cationic polyelectrolyte and carboxymethyl cellulose as the anionic polyelectrolyte to encapsulate polyethylene glycol by the vacuum impregnation method. Furthermore, the multi-walled carbon nanotube or graphene oxide, which were separately composited into the polyelectrolytes complex capsules to enhance thermal conductivity and light-to-thermal conversion efficiency. These capsules owned a typical core–shell structure, with an extremely high polyethylene glycol loading up to 34.33 g∙g‒1. After loading of polyethylene glycol, the resulted cellulose-based composite phase change materials exhibited high thermal energy storage ability with the latent heat up to 142.2 J∙g‒1, which was 98.5% of pure polyethylene glycol. Further results showed that the composite phase change materials demonstrated good form-stable property and thermal stability. Moreover, studies involving light-to-thermal conversion determined that composite phase change materials exhibited outstanding light-to-thermal conversion performance. Considering their exceptional comprehensive features, innovative composite phase change materials generated from cellulose presented a highly interesting choice for thermal management and renewable thermal energy storage.

关键词: cellulose     polyelectrolytes     phase change materials     thermal energy storage     light-to-thermal conversion    

Beyond bag of latent topics: spatial pyramid matching for scene category recognition

Fu-xiang LU,Jun HUANG

《信息与电子工程前沿(英文)》 2015年 第16卷 第10期   页码 817-828 doi: 10.1631/FITEE.1500070

摘要: We propose a heterogeneous, mid-level feature based method for recognizing natural scene categories. The proposed feature introduces spatial information among the latent topics by means of spatial pyramid, while the latent topics are obtained by using probabilistic latent semantic analysis (pLSA) based on the bag-of-words representation. The proposed feature always performs better than standard pLSA because the performance of pLSA is adversely affected in many cases due to the loss of spatial information. By combining various interest point detectors and local region descriptors used in the bag-of-words model, the proposed feature can make further improvement for diverse scene category recognition tasks. We also propose a two-stage framework for multi-class classification. In the first stage, for each of possible detector/descriptor pairs, adaptive boosting classifiers are employed to select the most discriminative topics and further compute posterior probabilities of an unknown image from those selected topics. The second stage uses the prod-max rule to combine information coming from multiple sources and assigns the unknown image to the scene category with the highest ‘final’ posterior probability. Experimental results on three benchmark scene datasets show that the proposed method exceeds most state-of-the-art methods.

关键词: Scene category recognition     Probabilistic latent semantic analysis     Bag-of-words     Adaptive boosting    

Construction and humoral immune response of Epstein-Barr virus latent membrane protein 2 DNA vaccine

Jianqing PAN PhD, Qin ZHANG MD, Daowen WANG MD, PhD,

《医学前沿(英文)》 2009年 第3卷 第4期   页码 390-395 doi: 10.1007/s11684-009-0087-5

摘要: We constructed a eukaryotic expression plasmid encoding Epstein-Barr virus latent membrane protein 2 (EBV, LMP2) and evaluated its effects on humoral immunity. First, the encoding sequence of the EBV was amplified from B95−8 cell RNA by reverse transcription polymerase chain reaction (RT-PCR) and then was directionally cloned into eukaryotic expression vector pcDNA3.1. It was employed to evaluate immune response of the mice inoculated doubly with the DNA vaccine. The serum antibody against LMP2 was detected with enzyme-linked immunosorbent assay (ELISA). The recombinant plasmid pcDNA3.1- was confirmed by the restrictive endonuclease analysis and sequence analysis. The serum titer of IgG antibody against LMP2 epitope in the mice immunized with the DNA vaccine encoding LMP2 was up to 1∶4000. In conclusion, the EBV DNA vaccine can induce a strong humoral immune response in mice.

关键词: Epstein-Barr virus     latent membrane protein 2     nasopharyngeal carcinoma     humoral immunity    

Diagnostic criteria of latent autoimmune diabetes in adults (LADA): a review and reflection

Yu Liao, Yufei Xiang, Zhiguang Zhou

《医学前沿(英文)》 2012年 第6卷 第3期   页码 243-247 doi: 10.1007/s11684-012-0201-y

摘要: Diabetes has become a major public health problem in China nowadays. There are almost 97 million diabetic patients nationwide. Latent autoimmune diabetes in adults (LADA) is a subtype of autoimmune diabetes. Although it has been reported for about 20 years, the diagnostic criteria of this disease remain controversial. The discussion mainly focused on serum autoantibodies, period of insulin need and age of diagnosis. Besides, β cell function, metabolic parameters, genetic factors and cell immunity may also contribute to the formulation of the criteria. Here, we aim to review and discuss the diagnostic criteria of latent autoimmune diabetes in adults.

关键词: LADA     diagnostic criteria     autoantibodies     insulin independence     age of diagnosis    

Combination form analysis and experimental study of mechanical properties on steel sheet glass fiber

《结构与土木工程前沿(英文)》 2021年 第15卷 第4期   页码 834-850 doi: 10.1007/s11709-021-0743-7

摘要: The concept of steel sheet glass fiber reinforced polymer (GFRP) composite bar (SSGCB) was put forward. An optimization plan was proposed in the combined form of SSGCB. The composite principle, material selection, and SSGCB preparation technology have been described in detail. Three-dimensional finite element analysis was adopted to perform the combination form optimization of different steel core structures and different steel core contents based on the mechanical properties. Mechanical tests such as uniaxial tensile, shear, and compressive tests were carried out on SSGCB. Parametric analysis was conducted to investigate the influence of steel content on the mechanical properties of SSGCB. The results revealed that the elastic modulus of SSGCB had improvements and increased with the rise of steel content. Shear strength was also increased with the addition of steel content. Furthermore, the yield state of SSGCB was similar to the steel bar, both of which indicated a multi-stage yield phenomenon. The compressive strength of SSGCB was lower than that of GFRP bars and increased with the increase of the steel core content. Stress-strain curves of SSGCB demonstrated that the nonlinear-stage characteristics of SSGCB-8 were much more obvious than other bars.

关键词: steel sheet GFRP composite bar     combination form     numerical modeling     mechanical properties test     strength    

General closed-form inverse kinematics for arbitrary three-joint subproblems based on the product of

《机械工程前沿(英文)》 2022年 第17卷 第2期 doi: 10.1007/s11465-022-0681-7

摘要: The inverse kinematics problems of robots are usually decomposed into several Paden–Kahan subproblems based on the product of exponential model. However, the simple combination of subproblems cannot solve all the inverse kinematics problems, and there is no common approach to solve arbitrary three-joint subproblems in an arbitrary postural relationship. The novel algebraic geometric (NAG) methods that obtain the general closed-form inverse kinematics for all types of three-joint subproblems are presented in this paper. The geometric and algebraic constraints are used as the conditions precedent to solve the inverse kinematics of three-joint subproblems. The NAG methods can be applied in the inverse kinematics of three-joint subproblems in an arbitrary postural relationship. The inverse kinematics simulations of all three-joint subproblems are implemented, and simulation results indicating that the inverse solutions are consistent with the given joint angles validate the general closed-form inverse kinematics. Huaque III minimally invasive surgical robot is used as the experimental platform for the simulation, and a master–slave tracking experiment is conducted to verify the NAG methods. The simulation result shows the inverse solutions and six sets given joint angles are consistent. Additionally, the mean and maximum of the master–slave tracking experiment for the closed-form solution are 0.1486 and 0.4777 mm, respectively, while the mean and maximum of the master–slave tracking experiment for the compensation method are 0.3188 and 0.6394 mm, respectively. The experiments results demonstrate that the closed-form solution is superior to the compensation method. The results verify the proposed general closed-form inverse kinematics based on the NAG methods.

关键词: inverse kinematics     Paden–Kahan subproblems     three-joint subproblems     product of exponential     closed-form solution    

堆积床相变储热系统中径向孔隙率振荡分布对热性能的影响 Article

刘红兵, 赵长颖

《工程(英文)》 2021年 第7卷 第4期   页码 515-525 doi: 10.1016/j.eng.2020.05.020

摘要:

由于具有较高的储热能力和传热速率,堆积床相变储热被认为是一种很有潜力的储热方法。在堆积床中,壁面效应会影响相变胶囊的填充结构,从而引起径向孔隙率的振荡。本研究建立了一个基于球体实际堆积过程的三维堆积床相变储热模型,以描述径向孔隙率的振荡分布,并分析了其内部的流动和传热情况。通过在堆积床中沿径向不同位置截取圆柱面,揭示了相变胶囊的排列与径向孔隙率之间的对应关系。径向孔隙率的振荡分布导致换热流体速度呈不均匀分布,因此相变材料的径向温度分布和液相分数分布进一步受到影响。此外,本文讨论了不同的无量纲参数(如管与胶囊的直径比、雷诺数和史蒂芬数)对换热流体和相变材料径向特性的影响。结果表明,不同的直径比对应于不同的径向孔隙率分布。此外,随着直径比的增加,在壁面附近区域换热流体速度显著变化,而中心区域换热流体速度的不均匀性将减小。雷诺数和史蒂芬数对换热流体的相对速度分布有轻微影响,而更高的雷诺数可导致速度成比例地提高,史蒂芬数的增加可加快堆积床相变储热系统的储热过程。

关键词: 堆积床相变储热     径向孔隙率振荡     流动换热     传热强化     直径比    

New form of geodetic coordinate system taking two length quantity as coordinate parameters

Yimin SHI, Ziyang ZHU, Yeming FAN

《结构与土木工程前沿(英文)》 2009年 第3卷 第1期   页码 105-110 doi: 10.1007/s11709-009-0014-5

摘要: A new form of geodetic coordinate system based on geodesic coordinates instead of geodetic longitude and latitude was proposed. The vertical and horizontal geodesic coordinates measured with length were defined as coordinate parameters, but the two families of coordinate curves were still meridians and parallel circles. The first fundamental form on the ellipsoidal surface and its three coefficients were deduced by the geodesic coordinate. The formula for the latitudinal scale factor of length for geodetic parallel lines was derived, by which the obtained result conformed to that standard value calculated from geodetic latitude, and it is applicable in the range of 400 km from north to south. Therefore, it lays the foundation for establishing the differential equation and differential relationship based on this type of coordinate parameters; and consequently, it is convenient and accurate enough to operate on the ellipsoidal surface in this new form of geodetic coordinate system.

关键词: geodetic coordinate system     meridian and parallel circle     coordinate parameter     the first fundamental form on the ellipsoidal surface     latitudinal scale factor of length    

Subcellular distribution and chemical form of Pb in hyperaccumulator

Yanqun ZU,Yuan LI,Huan MIN,Fangdong ZHAN,Li QIN,Jixiu WANG

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 250-258 doi: 10.1007/s11783-014-0643-3

摘要: Solution culture was conducted in order to understand accumulation characteristics and chemical forms of Pb in ( ) and the response of root exudates to Pb addition. The results showed that: 1) Pb contents in the shoot and root of increased with increasing in Pb concentrations in solution. 2) The contents of Pb chemical forms under Pb addition followed as: HAc extractable fraction (F )>HCl extractable fraction (F )>NaCl extractable fraction (F )>ethanol-extractable fraction (F )>water extractable fraction (F ). 3) Increased Pb level in the medium caused increases in Pb contents in the four subcellular fractions of shoots and roots, with most accumulation in FIV (Fraction IV, soluble fraction) in shoots and FI (Fraction I, cell wall fraction) in roots. 4) Contents of soluble sugar and free amino acid of root exudates increased with increasing Pb concentration in solution. Significantly positive correlations between Pb and contents of soluble sugar and free amino acid were observed. 5) With Pb concentrations in solution, low molecular weight organic acids (LMWOAs) contents followed the tendency: tartaric acid>acetic acid>malic acid>citric acid. Significantly positive correlation was observed between Pb and citric acid contents. The results indicate that soluble sugars, free amino acid and citric acid in root exudates of facilitate the absorption and accumulation of Pb, which exist in NaCl-, HCl- and HAc- extractable Pb forms, FI and FIV fractions, resulting in tolerance of to Pb.

关键词: Pb     Arenaria orbiculata     chemical forms     subcellular distribution     root exudates     hydroponic culture    

Generation of closed-form inverse kinematics for reconfigurable robots

ZHAO Jie, WANG Weizhong, GAO Yongsheng, CAI Hegao

《机械工程前沿(英文)》 2008年 第3卷 第1期   页码 91-96 doi: 10.1007/s11465-008-0013-6

摘要: For reconfigurable robots, the automatic generation of inverse kinematics is a key problem, because such robots may assume various configurations. In this paper, the screw and product-of-exponentials (POE) formula are used to model the kinematics of reconfigurable robots. The POE formula can be converted to canonical subproblems through decomposition and adjoint transformation. Three classes and 28 types of subproblems containing geometric or algebraic solutions are identified and solved, which can be reused in different configurations. A generalized, decomposable, and reusable approach for close-form inverse kinematics of reconfigurable robots is developed based on POE and subproblems. The effectiveness of this method is shown in an example.

关键词: different     effectiveness     generation     reconfigurable     algebraic    

虚拟企业是企业发展的新形式

李昕,李冀

《中国工程科学》 2001年 第3卷 第9期   页码 81-85

摘要:

文章试图应用现代管理的新理论,剖析知识经济时代企业的一种新形式--虚拟企业的产生和发展,指出其类型、特点及其优势,并对如何促进虚拟企业在我国的健康发展提出了见解。

关键词: 知识经济     虚拟企业     企业新形式    

Fabrication of form stable NaCl-Al2O3 composite for thermal energy storage by cold sintering process

Bilyaminu Suleiman, Qinghua Yu, Yulong Ding, Yongliang Li

《化学科学与工程前沿(英文)》 2019年 第13卷 第4期   页码 727-735 doi: 10.1007/s11705-019-1823-2

摘要: A form stable NaCl-Al O (50-50 wt-%) composite material for high temperature thermal energy storage was fabricated by cold sintering process, a process recently applied to the densification of ceramics at low temperature ˂ 300°C under uniaxial pressure in the presence of small amount of transient liquid. The fabricated composite achieved as high as 98.65% of the theoretical density. The NaCl-Al O composite also retained the chloride salt without leakage after 30 heating-cooling cycles between 750°C–850°C together with a holding period of 24 h at 850°C. X-ray diffraction measurements indicated congruent solubility of the alumina in chloride salt, excellent compatibility of NaCl with Al O , and chemical stability at high temperature. Structural analysis by scanning electron microscope also showed limited grain growth, high density, uniform NaCl distribution and clear faceted composite structure without inter-diffusion. The latent heat storage density of 252.5 J/g was obtained from simultaneous thermal analysis. Fracture strength test showed high sintered strength around 5 GPa after 50 min. The composite was found to have fair mass losses due to volatilization. Overall, cold sintering process has the potential to be an efficient, safe and cost-effective strategy for the fabrication of high temperature thermal energy storage materials.

关键词: cold sintering process     composite fabrication     thermal energy storage     phase change materials    

Investigation of the structural form optimization methods of high-rise buildings

ZHANG Shihai, WANG Li, OU Jinping, WANG Guangyuan

《结构与土木工程前沿(英文)》 2007年 第1卷 第2期   页码 182-187 doi: 10.1007/s11709-007-0020-4

摘要: In this paper, the structural form optimization methods of high-rise buildings based on the expert system (ES), case-based reasoning (CBR), and knowledge discovery in database (KDD) are evaluated systematically. The characteristics and shortcomings of each method are pointed out. It is predicted that the incorporation of these three techniques into an intelligent form optimization method will be an important development direction in the future. Finally, the unified intelligent form selection model combined with concepts of ES, CBR, KDD and artificially intelligent beautification is proposed. In consideration of the needs of human beings, machinery and computation, the model has been used for structural design combined with relevant knowledge, means, maneuver and strategy. The model plays an important role and has practical value in the process of artificially intelligent form optimization. It effectively reduces the blindness and failure of computer-aided structural design.

关键词: case-based reasoning     computation     KDD     important development     high-rise    

Neighborhood form and CO

Jiaxing GUO, Huan LIU, Yang JIANG, Dongquan HE, Qidong WANG, Fei MENG, Kebin HE

《环境科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 79-88 doi: 10.1007/s11783-013-0516-1

摘要: To understand the household CO emission level in China, as well as how much the neighborhoods’ socio-economic or design factors could influence the CO emission, 23 neighborhoods in Jinan were investigated in 2009 and 2010. These neighborhoods fall into four different types: superblock, enclave, grid and traditional. The household CO emission includes sources of both in-home energy use and passenger transportation. The average CO emission per household is 7.66 t·a , including 6.87 t in-home operational emission and 792 kg transportation emission. The household CO emission by neighborhood categories is 10.97, 5.65, 6.49, 5.40 t·household ·a for superblock, enclave, grid and traditional respectively. Superblock has the highest average emission and also the highest percent (more than 25%) of transportation emission among four different types of neighborhoods. The residential CO emission of superblock neighborhoods in Jinan has already reached the level in developed countries nearly ten years ago. It is predictable that more superblock neighborhoods would be built in China with the fast urbanization. How to avoid the rapid household CO emission growth in the future would be a systematic issue. The study also found that in addition to income and apartment area, household density, land use mix and accessibility to public transportation are three primary factors which have significant impacts on CO emission. High density, mixed land use and convenient accessibility to public transportation tend to reduce household CO emission.

关键词: CO2 emission     neighborhood type     transportation     household energy     China    

标题 作者 时间 类型 操作

Intracellular and extracellular TGF-β signaling in cancer: some recent topics

null

期刊论文

Encapsulation of polyethylene glycol in cellulose-based porous capsules for latent heat storage and light-to-thermal

期刊论文

Beyond bag of latent topics: spatial pyramid matching for scene category recognition

Fu-xiang LU,Jun HUANG

期刊论文

Construction and humoral immune response of Epstein-Barr virus latent membrane protein 2 DNA vaccine

Jianqing PAN PhD, Qin ZHANG MD, Daowen WANG MD, PhD,

期刊论文

Diagnostic criteria of latent autoimmune diabetes in adults (LADA): a review and reflection

Yu Liao, Yufei Xiang, Zhiguang Zhou

期刊论文

Combination form analysis and experimental study of mechanical properties on steel sheet glass fiber

期刊论文

General closed-form inverse kinematics for arbitrary three-joint subproblems based on the product of

期刊论文

堆积床相变储热系统中径向孔隙率振荡分布对热性能的影响

刘红兵, 赵长颖

期刊论文

New form of geodetic coordinate system taking two length quantity as coordinate parameters

Yimin SHI, Ziyang ZHU, Yeming FAN

期刊论文

Subcellular distribution and chemical form of Pb in hyperaccumulator

Yanqun ZU,Yuan LI,Huan MIN,Fangdong ZHAN,Li QIN,Jixiu WANG

期刊论文

Generation of closed-form inverse kinematics for reconfigurable robots

ZHAO Jie, WANG Weizhong, GAO Yongsheng, CAI Hegao

期刊论文

虚拟企业是企业发展的新形式

李昕,李冀

期刊论文

Fabrication of form stable NaCl-Al2O3 composite for thermal energy storage by cold sintering process

Bilyaminu Suleiman, Qinghua Yu, Yulong Ding, Yongliang Li

期刊论文

Investigation of the structural form optimization methods of high-rise buildings

ZHANG Shihai, WANG Li, OU Jinping, WANG Guangyuan

期刊论文

Neighborhood form and CO

Jiaxing GUO, Huan LIU, Yang JIANG, Dongquan HE, Qidong WANG, Fei MENG, Kebin HE

期刊论文