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可拓检测技术 被引量:20
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作者 余永权 《中国工程科学》 2001年第4期88-94,共7页
检测技术是目前多种学科的关键技术 ,检测中有两个难题 :一个是无法检测的问题 ,另一个是检测精度提高的问题。基于可拓学矛盾转化的思想方法 ,提出了一种与传统检测技术不同的新技术———可拓检测 ,这种检测技术利用可拓学的物元概念... 检测技术是目前多种学科的关键技术 ,检测中有两个难题 :一个是无法检测的问题 ,另一个是检测精度提高的问题。基于可拓学矛盾转化的思想方法 ,提出了一种与传统检测技术不同的新技术———可拓检测 ,这种检测技术利用可拓学的物元概念及相关方法 ,从矛盾转化去研究检测技术 ,以解决无法检测的物理量检测问题。文章给出了可拓检测的有关概念 ,基本原理及结构 ,并且提出了有关的实施方法和应用实例。 展开更多
关键词 物理量 可拓检测 可拓学 检测原理 物元变换 物元聚焦
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创伤后肘关节僵硬的手术治疗 被引量:21
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作者 鲍琨 姜佩珠 +3 位作者 于晓雯 陈东 马燕红 曾炳芳 《中华创伤骨科杂志》 CAS CSCD 2003年第4期308-311,共4页
目的报告手术松解和术后康复治疗外源性创伤后肘关节僵硬的方法和效果。方法自1999年12月~2002年2月,对14例肘关节僵硬进行手术松解,经内、外侧或联合入路,保留关节内侧副韧带的前束和外侧副韧带的尺束,彻底清除关节周围的异化骨,挛缩... 目的报告手术松解和术后康复治疗外源性创伤后肘关节僵硬的方法和效果。方法自1999年12月~2002年2月,对14例肘关节僵硬进行手术松解,经内、外侧或联合入路,保留关节内侧副韧带的前束和外侧副韧带的尺束,彻底清除关节周围的异化骨,挛缩的次要韧带和关节囊,恢复肘关节活动度。术后配合康复理疗。结果随访6~25个月,平均14.2个月。患肘关节的活动范围术后较术前平均增加75°;术后平均最大伸展度为7.9°,平均最大屈曲度为110.7°。无1例发生伤口感染,术后关节不稳,明显疼痛等并发症。依据Mayo肘关节功能评定标准,术前关节功能良3例,中9例,差2例;术后关节功能优11例,良2例,差1例。结论对于外源性创伤后肘关节僵硬,适时手术松解及术后康复有利于关节活动功能的恢复。 展开更多
关键词 创伤 肘关节僵硬 手术治疗 手术入路 康复训练
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Extrinsic harmful residues in Chinese herbal medicines: types,detection, and safety evaluation 被引量:13
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作者 Cong-min Liu Jia-an Qin +2 位作者 Xiao-wen Dou Mei-hua Yang Xiao-bo Sun 《Chinese Herbal Medicines》 CAS 2018年第2期117-136,共20页
Chinese herbal medicines(CHMs)are playing important roles in the treatment of diseases and human health care throughout the world.However,the extrinsic harmful residues have been threatening the therapies by destroy... Chinese herbal medicines(CHMs)are playing important roles in the treatment of diseases and human health care throughout the world.However,the extrinsic harmful residues have been threatening the therapies by destroying CHMs qualtiy which hinders the international trades of CHMs.This review summarized the extrinsic harmful residues contaminating CHMs in types,detection methods,national and international regulations,and made safety evaluations according to their contaminated levels,aiming to establish understanding among nations or organizations and provide references for the formulation or amendment of relative regulations. 展开更多
关键词 Chinese herbal medicines extrinsic harmful residues limit standards MONITOR REGULATIONS
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自修复高分子材料近五年的研究进展 被引量:15
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作者 陈晓丹 蒋国霞 《高分子通报》 CSCD 北大核心 2017年第8期39-47,共9页
自修复材料的概念源于对生物体自愈合现象的仿生研究,该类材料在受到损伤时可进行自修复并恢复一定程度的力学等性能。对高分子材料而言,其受机械力损伤后一般发生大分子链均裂或异裂而使材料产生微裂纹,此类微裂纹很难探测,而微裂纹的... 自修复材料的概念源于对生物体自愈合现象的仿生研究,该类材料在受到损伤时可进行自修复并恢复一定程度的力学等性能。对高分子材料而言,其受机械力损伤后一般发生大分子链均裂或异裂而使材料产生微裂纹,此类微裂纹很难探测,而微裂纹的产生往往会引起高分子材料失效,因此快速修复微裂纹对诸多工程领域的高分子材料来讲尤为重要。本文从外源型及本征型自修复高分子材料两个方面,综述了近五年自修复高分子材料的研究进展,并对其今后发展进行了展望。 展开更多
关键词 自修复 高分子材料 外援型 本征型
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Extrinsic calibration of a laser displacement sensor in a non-contact coordinate measuring machine 被引量:11
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作者 Chao BI Jianguo FANG +1 位作者 Kun LI Zhijun GUO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第4期1528-1537,共10页
In order to implement 3D scanning of those complicated parts such as blades in the aviation field,a non-contact optical measuring system is established in the paper,which integrates a laser displacement sensor,a probe... In order to implement 3D scanning of those complicated parts such as blades in the aviation field,a non-contact optical measuring system is established in the paper,which integrates a laser displacement sensor,a probe head,the frame of a coordinate measuring machine(CMM),etc.As the output of the laser sensor directly obtained possesses the 1D length of the laser beam,it needs to determine the unit direction vector of the laser beam denoted as(l,m,n)by calibration so as to convert the 1D values into 3D coordinates of target points.Therefore,an extrinsic calibration method based on a standard sphere is proposed to accomplish this task in the paper.During the calibration procedure,the laser sensor moves along with the motion of the CMM and gathers the required data on the spherical surface.Then,both the output of the laser sensor and the grating readings of the CMM are substituted into the constraint equation of the spherical surface,in which an over-determined nonlinear equation group containing unknown parameters is established.For the purpose of solving the equation group,a method based on non-linear least squares optimization is put forward.Finally,the system after calibration is utilized to measure the diameter of a metallic sphere 10 times from different orientations to verify the calibration accuracy.In the experiment,the errors between the measured results and the true values are all smaller than 0.03 mm,which manifests the validity and practicality of the extrinsic calibration method presented in the paper. 展开更多
关键词 CMM 3D scanning extrinsic calibration Laser displacement sensor Non-linear least squares
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Efficient Helicopter-Satellite Communication Scheme Based on Check-Hybrid LDPC Coding 被引量:10
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作者 Ping Wang Liuguo Yin Jianhua Lu 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2018年第3期323-332,共10页
When implementing helicopter-satellite communications, periodical interruption of the received signal is a challenging problem because the communication antenna is intermittently blocked by the rotating blades of the ... When implementing helicopter-satellite communications, periodical interruption of the received signal is a challenging problem because the communication antenna is intermittently blocked by the rotating blades of the helicopter. The helicopter-satellite channel model and the Forward Error Control(FEC) coding countermeasure are presented in this paper. On the basis of this model, Check-Hybrid(CH) Low-Density Parity-Check(LDPC)codes are designed to mitigate the periodical blockage over the helicopter-satellite channels. The CH-LDPC code is derived by replacing part of single parity-check code constraints in a Quasi-Cyclic LDPC(QC-LDPC) code by using more powerful linear block code constraints. In particular, a method of optimizing the CH-LDPC code ensemble by searching the best matching component code among a variety of linear block codes using extrinsic information transfer charts is proposed. Simulation results show that, the CH-LDPC coding scheme designed for the helicopter-satellite channels in this paper achieves more than 25% bandwidth efficiency improvement, compared with the FEC scheme that uses QC-LDPC codes. 展开更多
关键词 helicopter-satellite communications check-hybrid Low-Density Parity-Check(LDPC) codes extrinsic Information Transfer(EXIT) iterative decoding
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Design of Irregular QC-LDPC Code Based Multi-Level Coded Modulation Scheme for High Speed Optical Communication Systems 被引量:7
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作者 Liqian Wang Dongdong Wang +3 位作者 Yongjing Ni Xue Chen Midou Cui Fu Yang 《China Communications》 SCIE CSCD 2019年第5期106-120,共15页
In this paper, we focus on the design of irregular QC-LDPC code based multi-level coded modulation(MLCM) scheme by jointly optimizing the component code rate and the degree distribution of the irregular QC-LDPC compon... In this paper, we focus on the design of irregular QC-LDPC code based multi-level coded modulation(MLCM) scheme by jointly optimizing the component code rate and the degree distribution of the irregular QC-LDPC component code. Firstly, the sub-channel capacities of MLCM systems is analyzed and discussed, based on which the optimal component code rate can be obtained. Secondly, an extrinsic information transfer chart based two-stage searching algorithm is proposed to find the good irregular QC-LDPC code ensembles with optimal component code rates for their corresponding sub-channels. Finally, by constructing the irregular QC-LDPC component codes from the designed ensembles with the aim of possibly enlarging the girth and reducing the number of the shortest cycles, the designed irregular QC-LDPC code based 16QAM and 64QAM MLCM systems can achieve 0.4 dB and 1.2 dB net coding gain, respectively, compared with the recently proposed regular QC-LDPC code based 16QAM and 64QAM MLCM systems. 展开更多
关键词 quasi-cyclic LOW-DENSITY parity check (QC-LDPC) code irregular extrinsic INFORMATION transfer(EXIT) chart generalized mutual information(GMI) MULTI-LEVEL coded modulation(MLCM)
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A New Algorithm for the Establishing Data Association Between a Camera and a 2-D LIDAR 被引量:6
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作者 Lipu Zhou Zhidong Deng 《Tsinghua Science and Technology》 SCIE EI CAS 2014年第3期314-322,共9页
In this paper,we propose a new algorithm to establish the data association between a camera and a 2-D Light Detection And Ranging sensor (LIDAR).In contrast to the previous works,where data association is establishe... In this paper,we propose a new algorithm to establish the data association between a camera and a 2-D Light Detection And Ranging sensor (LIDAR).In contrast to the previous works,where data association is established by calibrating the intrinsic parameters of the camera and the extrinsic parameters of the camera and the LIDAR,we formulate the map between laser points and pixels as a 2-D homography.The line-point correspondence is employed to construct geometric constraint on the homography matrix.This enables checkerboard to be not essential and any object with straight boundary can be an effective target.The calculation of the 2-D homography matrix consists of a linear least-squares solution of a homogeneous system followed by a nonlinear minimization of the geometric error in the image plane.Since the measurement quality impacts on the accuracy of the result,we investigate the equivalent constraint and show that placing the calibration target nearby the 2-D LIDAR will provide sufficient constraints to calculate the 2-D homography matrix.Simulation and experimental results validate that the proposed algorithm is robust and accurate.Compared with the previous works,which require two calibration processes and special calibration targets such as checkerboard,our method is more flexible and easier to perform. 展开更多
关键词 sensor fusion 2-D homography extrinsic calibration camera calibration
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Effects of B[a]P-UVA Co-Exposure on Epigenetic Marks of Isolated Skin Cells and Impact of an Arundo donax L. Extract of These Changes
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作者 Marie M. Dorr Magali Favre-Mercuret +1 位作者 Katell Vié Richard Fitoussi 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第3期253-269,共17页
Background: Extrinsic aging results from environmental stressors such as UVR or pollutants. While the effects of single pollutants are better understood, those of their combination remain poorly scrutinized. Objective... Background: Extrinsic aging results from environmental stressors such as UVR or pollutants. While the effects of single pollutants are better understood, those of their combination remain poorly scrutinized. Objective: Building on a study showing downregulation of several processes upon co-exposure to B[a]P and UVA, we investigated changes induced by epigenetic marks. Materials and Methods: Human primary fibroblasts and HaCaT cells were exposed to B[a]P and UVA. After 24 hours, exposed and unexposed cells were compared to assess DNA methylation. Focusing on HaCaT, multiplex assays enabled quantifying histone H3 modifications and evaluating four splicing factors (SRSF1, SRSF3, SFPQ, and SF3B1) by immunohistochemical labeling. The expression of keratinocyte-/fibroblast-relevant genes was assessed by RT-qPCR. Finally, the impact of an Arundo donax L. extract added 24 hours before B[a]P-UVA co-exposure was analyzed. Results: Exposure to B[a]P-UVA raised DNA methylation (HaCaT: ×3.6, fibroblasts: ×1.9), an increase prevented by the extract. In HaCaT cells, B[a]P-UVA increases the frequency of S10P (+38%). When exposure was preceded by extract treatment, the frequency of several methylations was impacted. B[a]P-UVA only induced the expression of SRSF1 and SFPQ in HaCaT (+46% and +34%). Treatment with the extract abolished this effect. Co-exposure increases the expression of inflammation-related genes (IL-1α, IL-1β) in HaCaT cells and decreases those of AQP3, KRT15, and SOD2. The extract has little effect on these changes. In primary fibroblasts, exposure to B[a]P-UVA lowered the expression of LOXL2, LUM, and TGFBR2 (−38%, −59%, and −51%, respectively), and the extract did not affect these modifications. Conclusion: Within 24 hours, a single B[a]P-UVA co-exposure changes epigenetic marks of skin cells but has only mild effects on gene expression. An Arundo donax L. extract can prevent part of the epigenetic marks’ changes and could stimulate the expression of some genes in primary fibroblasts. 展开更多
关键词 extrinsic Aging DNA Methylation Histone H3 Splicing Factors Arundo donax L.
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Factors that influence adult neurogenesis as potential therapy 被引量:8
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作者 Belal Shohayeb Mohamed Diab +1 位作者 Mazen Ahmed Dominic Chi Hiung Ng 《Translational Neurodegeneration》 SCIE CAS 2018年第1期24-42,共19页
Adult neurogenesis involves persistent proliferative neuroprogenitor populations that reside within distinct regions of the brain.This phenomenon was first described over 50 years ago and it is now firmly established ... Adult neurogenesis involves persistent proliferative neuroprogenitor populations that reside within distinct regions of the brain.This phenomenon was first described over 50 years ago and it is now firmly established that new neurons are continually generated in distinct regions of the adult brain.The potential of enhancing the neurogenic process lies in improved brain cognition and neuronal plasticity particularly in the context of neuronal injury and neurodegenerative disorders.In addition,adult neurogenesis might also play a role in mood and affective disorders.The factors that regulate adult neurogenesis have been broadly studied.However,the underlying molecular mechanisms of regulating neurogenesis are still not fully defined.In this review,we will provide critical analysis of our current understanding of the factors and molecular mechanisms that determine neurogenesis.We will further discuss pre-clinical and clinical studies that have investigated the potential of modulating neurogenesis as therapeutic intervention in neurodegeneration. 展开更多
关键词 NICHE NEUROTROPHINS CYTOKINES Transcription factors Stem cells extrinsic factors THERAPY
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Operationalizing physical literacy for learners: Embodying the motivation to move 被引量:8
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作者 Ang Chen 《Journal of Sport and Health Science》 SCIE 2015年第2期125-131,共7页
Physical literacy is a concept that is expected to encompass the mind and body in an integrated way to explain, promote, and help sustain human beings' fundamental function: movement. According to Whitehead(2010),... Physical literacy is a concept that is expected to encompass the mind and body in an integrated way to explain, promote, and help sustain human beings' fundamental function: movement. According to Whitehead(2010), physical literacy is defined by motivation, especially by competence-based and interest-based motivation. This point of view is consistent with vast amount of research evidence on children and adolescents' physical activity behavior. In the article I attempt to interpret and operationalize physical literacy from a perspective that children's motivation in physical education is both an innate mental disposition and an acquired/learned attribute. Particularly I rely on the conceptual learning theory and motivation regulation mechanisms of the self-determination theory to argue that in physical education, children should experience tasks that inspire them to embody competence and interest along with self-regulation strategies necessary for developing and sustaining the motivation to move. 展开更多
关键词 extrinsic motivation Intrinsic motivation Motivation embodiment Physical literacy
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Prediction of return of spontaneous circulation in outof-hospital cardiac arrest with non-shockable initial rhythm using point-of-care testing: a retrospective observational study 被引量:3
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作者 Kota Shinada Hiroyuki Koami +1 位作者 Ayaka Matsuoka Yuichiro Sakamoto 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第2期89-95,共7页
BACKGROUND:Out-of-hospital cardiac arrest(OHCA) is a public health concern, and many studies have been conducted on return of spontaneous circulation(ROSC) and its prognostic factors.Rotational thromboelastometry(ROTE... BACKGROUND:Out-of-hospital cardiac arrest(OHCA) is a public health concern, and many studies have been conducted on return of spontaneous circulation(ROSC) and its prognostic factors.Rotational thromboelastometry(ROTEM?), a point-of-care testing(POCT) method, has been useful for predicting ROSC in patients with OHCA, but very few studies have focused on patients with non-shockable rhythm. We examined whether the parameters of POCT could predict ROSC in patients with OHCA and accompanying non-shockable rhythm.METHODS:This is a single-center, retrospective observational study. Complete blood count,blood gas, and ROTEM POCT measurements were used. This study included patients with nontraumatic OHCA aged 18 years or older who were transported to the emergency department and evaluated using POCT between January 2013 and December 2021. The patients were divided into the ROSC and non-ROSC groups. Prehospital information and POCT parameters were compared using receiver operating characteristic(ROC) curve analysis, and further logistic regression analysis was performed.RESULTS:Sixty-seven and 135 patients were in the ROSC and non-ROSC groups,respectively. The ROC curves showed a high area under the curve(AUC) for K^(+) of 0.77(95%confidence interval [CI]:0.71–0.83) and EXTEM amplitude 5 min after clotting time(A5) of 0.70(95%CI:0.62–0.77). The odds ratios for ROSC were as follows:female sex 3.67(95%CI:1.67–8.04);K^(+)0.64(95%CI:0.48–0.84);and EXTEM A5 1.03(95%CI:1.01–1.06).CONCLUSION:In OHCA patients with non-shockable rhythm, K^(+) level and the ROTEM parameter EXTEM A5 may be useful in predicting ROSC. 展开更多
关键词 Rotational thromboelastometry Blood coagulation disorders extrinsic pathway POTASSIUM
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外援型聚合物基自修复复合材料研究进展 被引量:7
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作者 申艳娇 杨涛 +1 位作者 牛雪娟 杜宇 《玻璃钢/复合材料》 CAS CSCD 北大核心 2015年第1期92-96,63,共6页
聚合物基自修复复合材料是一种重要的的智能复合材料。本文就近年来聚合物基自修复复合材料的研究进展进行了系统综述,并以外援型热固性聚合物基自修复复合材料为重点,详细介绍了几种典型的外援型修复方法,主要包括微胶囊型自修复、中... 聚合物基自修复复合材料是一种重要的的智能复合材料。本文就近年来聚合物基自修复复合材料的研究进展进行了系统综述,并以外援型热固性聚合物基自修复复合材料为重点,详细介绍了几种典型的外援型修复方法,主要包括微胶囊型自修复、中空纤维型自修复、微脉管型自修复、热塑性自修复,系统地阐述了这几种自修复方法的修复机理及特点并分析比较其优劣,展望了聚合物基自修复复合材料的应用前景及发展方向。 展开更多
关键词 聚合物 自修复复合材料 热固性 外援型
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Selective protection of glycinebetaine on extrinsic polypeptides of PS Ⅱ particles 被引量:4
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作者 HOU Caixia, XU Chunhe, TANG Zhangcheng and SHEN YunkangShanghai Institute of Plant Physiology, Chinese Academy of Sciences, Shanghai 200032, China 《Chinese Science Bulletin》 SCIE EI CAS 1997年第20期1744-1748,共5页
PHOTOSYSTEM Ⅱ(PS Ⅱ) particles capable of O<sub>2</sub> evolution contain D1, D2 transmembrane pro-teins, and three extrinsic polypeptides which are exposed to the outer aqueous phase with ap-parent mol... PHOTOSYSTEM Ⅱ(PS Ⅱ) particles capable of O<sub>2</sub> evolution contain D1, D2 transmembrane pro-teins, and three extrinsic polypeptides which are exposed to the outer aqueous phase with ap-parent molecular masses of 33, 23, 18 kD. The three proteins can be partially or totally re-moved by treating the PS Ⅱ membranes with high concentrations of salt or other methods, 展开更多
关键词 GLYCINEBETAINE extrinsic POLYPEPTIDES trichloroacetate NaCI.
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Thermal stability of oxygen evolution in photosystem Ⅱ core complex in the presence of digalactosyl diacylglycerol 被引量:3
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作者 YANG Zhenle, LI Liangbi & KUANG TingyunPhotosynthesis Research Center, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China 《Chinese Science Bulletin》 SCIE EI CAS 2002年第24期2089-2092,共4页
The influence of digalactosyldiacylglycerol (DGDG), one of the photosynthetic membrane lipids, on heat inactivation of the process of oxygen evolution has been studied in vitro in photosystem Ⅱ(PS Ⅱ) core complex. I... The influence of digalactosyldiacylglycerol (DGDG), one of the photosynthetic membrane lipids, on heat inactivation of the process of oxygen evolution has been studied in vitro in photosystem Ⅱ(PS Ⅱ) core complex. It was found that the temperature of semi-inactivation of oxygen evolution in the complex increased from 40.0 to about 43.0℃ in the presence of DGDG with 5-min heat treatment in the dark. Furthermore, when PS Ⅱ core complex was incubated for 5 min at 45.0℃, the oxygen evolution in the complex was completely lost, whilst the DGDG-complexed PS Ⅱ core complex still retained a 16% of activity (100% for 25.0℃). In addition, a 1-h incubation at 38.0℃ inactivated absolutely the oxygen evolution for the PS Ⅱ core complex. By contrast, there remained about 20% of activity (zero time for 100%) for the complex in the presence of DGDG under the same condition. These results indicate a new role of DGDG in the protection of PS Ⅱ core complex against the deleterious effects of temperature. It was 展开更多
关键词 digalactosyl DIACYLGLYCEROL PHOTOSYSTEM core complex extrinsic protein of 33 KD thermal stability OXYGEN evolution.
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微胶囊型自修复高分子材料的研究进展 被引量:6
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作者 杜逸纯 刘治华 《皮革与化工》 CAS 2020年第4期24-28,35,共6页
目前外援型自修复高分子材料主要通过往高分子基体中添加修复剂来制备,根据不同的载体可分为空心纤维自修复、纳米粒子自修复、微胶囊自修复、微脉管自修复以及碳纳米管自修复五种。本文回顾了微胶囊型自修复高分子材料的研究进展与应用... 目前外援型自修复高分子材料主要通过往高分子基体中添加修复剂来制备,根据不同的载体可分为空心纤维自修复、纳米粒子自修复、微胶囊自修复、微脉管自修复以及碳纳米管自修复五种。本文回顾了微胶囊型自修复高分子材料的研究进展与应用,介绍了双环戊二烯自修复体系、异氰酸酯自修复体系、环氧树脂自修复体系、马来酰亚胺基自修复体系这四种比较重要的自修复体系的自修复原理及应用,对目前微胶囊型自修复高分子材料仍存在的问题进行分析,并对其发展方向进行展望。 展开更多
关键词 外援型 微胶囊 自修复机理 高分子 自修复材料
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Spatially Coupled Codes via Bidirectional Block Markov Superposition Transmission
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作者 Gaoyan Li Shancheng Zhao +1 位作者 Haiqiang Chen Jinming Wen 《Tsinghua Science and Technology》 SCIE EI CAS CSCD 2024年第3期656-670,共15页
In this paper,we present a new class of spatially coupled codes obtained by using both non-recursive and recursive block-oriented superposition.The resulting codes are termed as bidirectional block Markov superpositio... In this paper,we present a new class of spatially coupled codes obtained by using both non-recursive and recursive block-oriented superposition.The resulting codes are termed as bidirectional block Markov superposition transmission(BiBMST)codes.Firstly,we perform an iterative decoding threshold analysis according to protograph-based extrinsic information transfer(PEXIT)charts for the BiBMST codes over the binary erasure channels(BECs).Secondly,we derive the generator and parity-check matrices of the BiBMST codes.Thirdly,extensive numerical results are presented to show the advantages of the proposed BiBMST codes.Particularly,our numerical results show that,under the constraint of an equal decoding latency,the BiBMST codes perform better than the recursive BMST(rBMST)codes.However,the simulation results show that,in finite-length regime,negligible performance gain is obtained by increasing the encoding memory.We solve this limitation by introducing partial superposition,and the resulting codes are termed as partially-connected BiBMST(PC-BiBMST)code.Analytical results have confirmed the advantages of the PC-BiBMST codes over the original BiBMST codes.We also present extensive simulation results to show the performance advantages of the PC-BiBMST codes over the spatially coupled low-density parity-check(SC-LDPC)codes,spatially coupled generalized LDPC(SC-GLDPC)codes,and the original BiBMST codes in the finite-length regime. 展开更多
关键词 block Markov superposition transmission(BMST) protograph-based extrinsic information transfer(PEXIT) capacity-approaching codes spatial coupling
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Stable transfection of extrinsic Smac gene enhances apoptosis-inducing effects of chemotherapeutic drugs on gastric cancer cells 被引量:5
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作者 Li-DuanZheng Qiang-SongTong +2 位作者 LiangWang JunLiu WeiQian 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第1期79-83,共5页
AIM: To explore the feasibility of enhancing apoptosis-inducing effects of chemotherapeutic drugs on human gastric cancer cells by stable transfection of extrinsic Smac gene. METHODS: After Smac gene was transferred i... AIM: To explore the feasibility of enhancing apoptosis-inducing effects of chemotherapeutic drugs on human gastric cancer cells by stable transfection of extrinsic Smac gene. METHODS: After Smac gene was transferred into gastric cancer cell line MKN-45, subclone cells were obtained by persistent G_(418) selection. Cellular Smac gene expression was determined by RT-PCR and Western blotting. After treatment with mitomycin (MMC) as an apoptotic inducer, in vitro cell growth activities were investigated by trypan blue-staining method and MTT colorimetry. Cell apoptosis and its rates were determined by electronic microscopy, annexin V-FTTC and propidium iodide staining flow cytometry. Cellular caspase-3 protein expression and its activities were assayed by Western blotting and colorimetry. RESULTS: When compared with MKN-45 cells, the selected subclone cell line MKN-45/Smac had significantly higher Smac mRNA (3.12±0.21 vs 0.82±0.14, t=7.52, P<0.01) and protein levels (4.02±0.24 vs0.98±0.11, t=8.32, P<0.01). After treatment with 10 μg/mL MMC for 6-24 h, growth inhibition rate of MKN-45/Smac (15.8±1.2-54.8±2.9%) was significantly higher than that of MKN-45 (5.8±0.4-24.0±1.5%, t=6.42, P<0.01). Partial MKN-45/Smac cancer cells presented characteristic morphological changes of apoptosis under the electronic microscope with an apoptosis rate of 36.4±2.1%, which was significantly higher than that of MKN-45 (15.2±0.8%, t=9.25, P<0.01). Compared with MKN-45, caspase-3 expression levels in MKN-45/Smac were improved significantly (3.39±0.42 vs0.96±0.14, t=8.63, P<0.01), while its activities were 3.25 times as many as those of MKN-45 (0.364±0.010 vs0.112±0.007, t=6.34, P<0.01). CONCLUSION: Stable transfection of extrinsic Smac gene and its over-expression in gastric cancer cell line can significantly enhance cellular caspase-3 expression and activities, ameliorate apoptosis-inducing effects of mitomycin C on cancer cells, which is a novel strategy to improve chemotherapeutic effects on gastric cancer. 展开更多
关键词 Gastric cancer Mitomycin C extrinsic Smac gene APOPTOSIS TRANSFECTION
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A Practical Regular LDPC Coded Scheme for Physical-Layer Information Security
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作者 Du Junyi 《China Communications》 SCIE CSCD 2024年第5期190-201,共12页
In this paper,we aim to design a practical low complexity low-density parity-check(LDPC)coded scheme to build a secure open channel and protect information from eavesdropping.To this end,we first propose a punctured L... In this paper,we aim to design a practical low complexity low-density parity-check(LDPC)coded scheme to build a secure open channel and protect information from eavesdropping.To this end,we first propose a punctured LDPC coded scheme,where the information bits in a codeword are punctured and only the parity check bits are transmitted to the receiver.We further propose a notion of check node type distribution and derive multi-edge type extrinsic information transfer functions to estimate the security performance,instead of the well-known weak metric bit error rate.We optimize the check node type distribution in terms of the signal-to-noise ratio(SNR)gap and modify the progressive edge growth algorithm to design finite-length codes.Numerical results show that our proposed scheme can achieve a lower computational complexity and a smaller security gap,compared to the existing scrambling and puncturing schemes. 展开更多
关键词 extrinsic information transfer function physical layer scheme secure open channel security gap
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Recent Developments in Fiber Optic Spectral White-Light Interferometry 被引量:6
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作者 Yi JIANG Wenhui DING 《Photonic Sensors》 SCIE EI 2011年第1期62-71,共10页
Recent developments in spectral white-light interferometry(WLI)are reviewed.Firstly,the techniques for obtaining optical spectrum are introduced.Secondly,some novel measurement techniques are reviewed,including the im... Recent developments in spectral white-light interferometry(WLI)are reviewed.Firstly,the techniques for obtaining optical spectrum are introduced.Secondly,some novel measurement techniques are reviewed,including the improved peak-to-peak WLI,improved wavelength-tracking WLI,Fourier transform WLI,and 3×3 coupler based WLI.Furthermore,a hybrid measurement for the intensity-type sensors,interferometric sensors,and fiber Bragg grating sensors is achieved.It is shown that these developments have assisted in the progress of WLI. 展开更多
关键词 Optical fiber sensors white-light interferometry optical path difference fiber Fabry-Perot tunable filter extrinsic Fabry-Perot interferometer
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