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学精悟透用好马克思主义
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作者 赵见伟 贺小瑞 胡国超 《中学政治教学参考》 北大核心 2019年第6期1-1,4,共2页
新时代,学精悟透用好马克思主义,具有重大的理论和实践意义。我们必须认真学习,把握精髓要义;透彻领悟,致力融会贯通;知行统一,坚持有效、用好。
关键词 学精 悟透 用好 马克思主义
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Improvement of High-Speed Detection Algorithm for Nonwoven Material Defects Based on Machine Vision 被引量:2
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作者 LI Chengzu WEI Kehan +4 位作者 ZHAO Yingbo TIAN Xuehui QIAN Yang ZHANG Lu WANG Rongwu 《Journal of Donghua University(English Edition)》 CAS 2024年第4期416-427,共12页
Defect detection is vital in the nonwoven material industry,ensuring surface quality before producing finished products.Recently,deep learning and computer vision advancements have revolutionized defect detection,maki... Defect detection is vital in the nonwoven material industry,ensuring surface quality before producing finished products.Recently,deep learning and computer vision advancements have revolutionized defect detection,making it a widely adopted approach in various industrial fields.This paper mainly studied the defect detection method for nonwoven materials based on the improved Nano Det-Plus model.Using the constructed samples of defects in nonwoven materials as the research objects,transfer learning experiments were conducted based on the Nano DetPlus object detection framework.Within this framework,the Backbone,path aggregation feature pyramid network(PAFPN)and Head network models were compared and trained through a process of freezing,with the ultimate aim of bolstering the model's feature extraction abilities and elevating detection accuracy.The half-precision quantization method was used to optimize the model after transfer learning experiments,reducing model weights and computational complexity to improve the detection speed.Performance comparisons were conducted between the improved model and the original Nano Det-Plus model,YOLO,SSD and other common industrial defect detection algorithms,validating that the improved methods based on transfer learning and semi-precision quantization enabled the model to meet the practical requirements of industrial production. 展开更多
关键词 defect detection nonwoven materials deep learning object detection algorithm transfer learning halfprecision quantization
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学精技能 让设备健康运行
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作者 徐志红 《班组天地》 2019年第2期17-17,共1页
我作为电检班班长,当一名技能高超的电检工,是我的不懈追求。在学技能,精技能的路上,必须不辞辛苦,勤奋耕耘,让设备健康运行。新的一年,我将继续紧跟科技发展步伐,时时更新专业知识,钻研并掌握新技术。一是向书本学,我购买了《电子技术... 我作为电检班班长,当一名技能高超的电检工,是我的不懈追求。在学技能,精技能的路上,必须不辞辛苦,勤奋耕耘,让设备健康运行。新的一年,我将继续紧跟科技发展步伐,时时更新专业知识,钻研并掌握新技术。一是向书本学,我购买了《电子技术》《电力传动》《自动化电器维修》等一大摞子电气专业书籍,充实大脑,用理论指导实践。 展开更多
关键词 学精 技术 书本 设备 步伐 时时 电力 专业知识 技能
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Iron reduction in aluminum by electroslag refining 被引量:4
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作者 陈冲 王俊 +4 位作者 疏达 薛菁 孙宝德 薛永生 阎庆敏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期964-969,共6页
The effect of electroslag refining on iron reduction from commercial aluminum was investigated.Cast electrodes of commercial aluminum were electroslag refined using KCl-NaCl-Na3AlF6 slag containing Na2B4O7.Experimenta... The effect of electroslag refining on iron reduction from commercial aluminum was investigated.Cast electrodes of commercial aluminum were electroslag refined using KCl-NaCl-Na3AlF6 slag containing Na2B4O7.Experimental results indicate that the iron content decreases with increasing Na2B4O7 addition and remelting time,and the iron content decreases from 0.400% to 0.184% under 9% Na2B4O7 addition for 30 min remelting.The elastic modulus,yield strength and ultimate tensile strength commercial aluminum are improved,and the tensile elongation is increased by 43% after electroslag refining.The chemical reaction between melt and slag to form Fe2B is the main reason for iron reduction and the thermodynamic calculation of the chemical reaction theoretically accounts for the formation of Fe2B. 展开更多
关键词 ALUMINUM electroslag refining IRON mechanical properties thermodynamic calculation
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Histological and immunocytochemical study of deferens ducts in the Chinese rat snake (Zaocys dhumnades)
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作者 梁刚 刘巧巧 +1 位作者 于虎虎 王琼霞 《Zoological Research》 CAS CSCD 北大核心 2011年第6期663-669,共7页
To investigate the relationship between structure and function of the deferens ducts in the Chinese rat snake (Zaocys dhumnades), morphological changes within an annual cycle were observed by routine histological te... To investigate the relationship between structure and function of the deferens ducts in the Chinese rat snake (Zaocys dhumnades), morphological changes within an annual cycle were observed by routine histological techniques. Also, the correlation of androgen receptor (AR), estrogen receptor (ER), progesterone receptor (PR) and aromatase (Ar) expressions in the vas deferens and testis were studied immunohistochemically. To confh'm that the sperm and the spherical structure existed in deferens ducts, we also used routine histological technique observed deferens ducts in the Striped-tailed rat-snake (Elaphe taeniura), Red-banded snake (Dinodon rufozonatum), and Tiger-spotted neck- troughed snake (Rhabdophis tigrina lateralis). The results showed that the deferens ducts of the Chinese Rat Snake were composed of efferent duct, epididymal duct and vas deferens. Efferent duct contained sperm from August-October, and the sperm were observed in the epididymal duct from August-the following January. Throughout the year (except July) a large number of sperm were present in the vas deferens where a previously unreported spherical structure formed by spermatids was observed, which showed no significant differences in the IOD values of AR-, ER-, PR- and Ar- immunoreactivities. Since the spermatids in the spherical structure were undergoing spermatogenesis and this phenomenon also existed in the Striped-tailed rat-snake and Red-banded snake, the term, seminiferous spherule, was named for this spherical structure This study demonstrated that the testis was the main site for snake spermiogenesis, and the seminiferous spherule in vas deferens was the other Both the epididymis and vas deferens stored sperm; however, the vas deferens was the main organ for sperm storage. 展开更多
关键词 Snakes Deferens ducts HISTOLOGY SPERMIOGENESIS Sperm storage
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Thermodynamics of removing impurities from crude lead by vacuum distillation refining 被引量:8
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作者 孔祥峰 杨斌 +3 位作者 熊恒 孔令鑫 刘大春 徐宝强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1946-1950,共5页
A novel technique was developed to remove impurities from crude lead by vacuum distillation.The thermodynamics on vacuum distillation refining process of crude lead was studied by means of saturated vapor pressure of ... A novel technique was developed to remove impurities from crude lead by vacuum distillation.The thermodynamics on vacuum distillation refining process of crude lead was studied by means of saturated vapor pressure of main components of crude lead,separation coefficients and vapor-liquid equilibrium composition of Pb-i(i stands for an impurity) system at different temperatures.The behaviors of impurities in the vacuum distillation refining process were investigated.The results show that the vacuum distillation should be taken to obtain lead from crude lead,in which Zn,As and partial Sb are volatilized at lower temperature of 923-1023 K.Lead is distilled from the residue containing Cu,Sn,Ag and Bi at higher temperature of 1323-1423 K,but the impurity Bi is also volatilized along with lead and cannot be separated from lead. 展开更多
关键词 crude lead vacuum distillation REFINING REMOVAL THERMODYNAMICS
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Boron removal in purifying metallurgical grade silicon by CaO-SiO_2 slag refining 被引量:9
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作者 伍继君 李彦龙 +3 位作者 马文会 魏奎先 杨斌 戴永年 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1231-1236,共6页
Boron removal from metallurgical grade silicon (MG-Si) using a calcium silicate slag was studied. The results show that it is impossible basically to remove boron using a pure SiO2 refining. The oxidizing ability of... Boron removal from metallurgical grade silicon (MG-Si) using a calcium silicate slag was studied. The results show that it is impossible basically to remove boron using a pure SiO2 refining. The oxidizing ability of CaO-SiO2 slag for boron removal was characterized by establishing the thermodynamic relationship between the distribution coefficient of boron (LB) and the activities of SiO2 and CaO. The experimental results show that the distribution coefficient and the removal efficiency of boron are greatly improved with the increase of CaO proportion in the slag. The maximal value of LB reaches 1.57 with a slag composition of 60%CaO-40%SiO2 (mass fraction). The boron content in the refined silicon is reduced from 18×10^-6 to 1.8×10^-6 using slag refining at 1600 ℃ for 3 h with a CaO-SiO2/MG-Si ratio of 2.5, and the removal efficiency of boron reaches 90%. 展开更多
关键词 metallurgical grade silicon boron removal THERMODYNAMICS distribution coefficient slag refining
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The Study on the Localization of Acid Phosphatase Activity During Spermiogenesis in Chinese Mitten-Handed Crab,Eriocheir sinensis
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作者 刘桂荣 康现江 +2 位作者 郭明申 孙文佳 王琦 《Marine Science Bulletin》 CAS 2007年第1期13-19,共7页
Ultrastructural cytochemical techniques and electron microscopy were used for localization of acid phosphatase activity during spermiogenesis in Eriocheir sinemsis. The results showed that: Acid phosphatase was synth... Ultrastructural cytochemical techniques and electron microscopy were used for localization of acid phosphatase activity during spermiogenesis in Eriocheir sinemsis. The results showed that: Acid phosphatase was synthesized in the endoplasmic reticulum in the early spermatids. The acid phosphatase was found gradually in nucleus, the membrane of acrosomal vesicle, the cytoplasmic region and the acrosomal tubule. And then the reaction product particles became thicker during the spermiogenesis. In the mature sperm, acid phosphatase was localized in the percutor organ slightly, but it was massive and compact in the acrosomal tubule. 展开更多
关键词 SPERMIOGENESIS Acid phosphatase Eriocheir sinensis
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INTELLIGENT PRECISION CONTROL IN CNC GRINDING
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作者 田新诚 王宁生 袁信 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期95-99,共5页
The development of intelligent control techniques provides powerful means for the control of machine tools. In this paper, a intelligent control technique and an algorithm for precision control of CNC grinding of cera... The development of intelligent control techniques provides powerful means for the control of machine tools. In this paper, a intelligent control technique and an algorithm for precision control of CNC grinding of ceramic chips are introduced. In the process of ceramic chip CNC grinding, the dimension of the chips tends to get larger and the dimensional error to exceed the tolerance as the number of the chips increases which are machined on the same part program. There are many factors leading to the occurrence of the error and the law of error variation is very complicated. With the introduced intelligent self learning error compensation technique, the CNC system can improve the control strategy to compensate the error automatically. The simulational result is also given. 展开更多
关键词 intelligent control self learning precision control ceramic chip
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Functional dyspepsia:Are psychosocial factors of relevance? 被引量:50
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作者 Sandra Barry Timothy G Dinan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第17期2701-2707,共7页
The pathogenesis of Functional Dyspepsia (FD) remains unclear, appears diverse and is thus inadequately understood. Akin to other functional gastrointestinal disorders, research has demonstrated an association betwe... The pathogenesis of Functional Dyspepsia (FD) remains unclear, appears diverse and is thus inadequately understood. Akin to other functional gastrointestinal disorders, research has demonstrated an association between this common diagnosis and psychosocial factors and psychiatric morbidity. Conceptualising the relevance of these factors within the syndrome of FD requires application of the biopsychosocial model of disease. Using this paradigm, dysregulation of the reciprocal communication between the brain and the gut is central to symptom generation, interpretation and exacerbation. Appreciation and understanding of the neurobiological correlates of various psychological states is also relevant. The view that psychosocial factors exert their influence in FD predominantly through motivation of health care seeking also persists. This appears too one-dimensional an assertion in light of the evidence available supporting a more intdnsic aetiological link. Evolving understanding of pathogenic mechanisms and the heterogeneous nature of the syndrome will facilitate effective management. Co-morbid psychiatric illness warrants treatment with conventional therapies. Acknowledging the relevance of psychosocial variables in FD, the degree of which is subject to vadation, has implications for assessment and management. Available evidence suggests psychological therapies may benefit FD patients particularly those with chronic symptoms. The rationale for use of psychotropic medications in FD is apparent but the evidence base to support the use of antidepressant pharmacotherapy is to date limited. 展开更多
关键词 Functional dyspepsia Psychosocial factors PSYCHIATRY PATHOPHYSIOLOGY
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ANALYSIS OF REGULATION AND HARMONIZATION IMPLIED IN A-B CLASSIC ON ACUPUNCTURE AND MOXIBUSTION
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作者 姜燕 马新平 《World Journal of Acupuncture-Moxibustion》 2007年第1期46-48,共3页
It aims to draw the conclusion that the ideas of treatment in Zhen Jiu Jia Yi Jing (《针灸甲乙经》, A-B Classic on Acupuncture and Moxibustion ) can be summarized as "regulation" and "harmonization" through the ... It aims to draw the conclusion that the ideas of treatment in Zhen Jiu Jia Yi Jing (《针灸甲乙经》, A-B Classic on Acupuncture and Moxibustion ) can be summarized as "regulation" and "harmonization" through the research of words in the Classic, such as "being normal", "regulation" and "harmonization". The lost of regulation of a normal person shows disharmony. Regulation can make the person-being-sick become harmony and back to "being normal". "Regulation" and "harmonization" right imply the quintessence of traditional Chinese medicine. 展开更多
关键词 A-B Classic on Acupuncture and Moxibustion Rgulation and harmonization Being normal
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Accuracy analysis of plane-strain bulge test for determining mechanical properties of thin films 被引量:3
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作者 杨林 龙士国 +1 位作者 马增胜 王子菡 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3265-3273,共9页
The effect of a variety of geometrics, initial conditions and material properties on the deformation behavior of thin films in the plane-strain bulge test was systematically scrutinized by performing the finite elemen... The effect of a variety of geometrics, initial conditions and material properties on the deformation behavior of thin films in the plane-strain bulge test was systematically scrutinized by performing the finite element analysis, and then the accuracy of the plane-strain bulge test in determining the mechanical properties of thin films in terms of our finite element results was analyzed. The results indicate that although the determination of the plane-strain modulus in the light of the plane-strain bulge equation is fairly accurate, the calculation of the residual stress is not satisfied as expected, especially for low residual stress. Finally, an approach is proposed for analyzing bulge test data, which will improve the accuracy and reliability of this bulge test technique. 展开更多
关键词 thin films mechanical properties bulge test ACCURACY finite element analysis
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Studies on preparations and analysis of essential oil from Chinese fir 被引量:11
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作者 黄洛华 秦特夫 大平辰郎 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期80-82,J004,共4页
Three steam distillation devices (D-1, D-2 and D-4) or one simultaneous distillation (D-3, water-diethyl ether) as well as the process of CO2-SFE (Supercritical fluid extraction) were adopted in extraction of essentia... Three steam distillation devices (D-1, D-2 and D-4) or one simultaneous distillation (D-3, water-diethyl ether) as well as the process of CO2-SFE (Supercritical fluid extraction) were adopted in extraction of essential oils from Chinese-fir (Cunninghamia lancedata (Lamb) Hook.) and the chemical components of the extracted essential oil were analyzed by Gas chromatograph-MS analyses. The results showed that the essential oil could be almost extracted out within 2 hours and the device-3 had the highest extraction efficiency. The major chemical component of the oil was cedrol. The yield of the extracted essential oils from Chinese fir decreased gradually with the increase of the distillation time. The best condition for extraction by means of CO2-SFE is 100 kg·cm?2 in pressure and 40°C in temperature for. Keywords Chinese fir - Essential oil - Cedrol - Supercritical fluid extraction CLC number S781.4 Document code A Foundation item: This paper was support by the Key Foundation Research Project (G1999016001) of China and the Japan International Cooperation AgencyBiography: HUANG Luo-hua (1957-), male, Research associate, Research Institute of Wood Industry, Chinese Academy of forestry, Beijing 100091, P. R. ChinaResponsible editor: Song Funan 展开更多
关键词 Chinese fir Essential oil CEDROL Supercritical fluid extraction
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Exact Solution of Quantum Dynamics of a Cantilever Coupling to a Single Trapped Ultracold Ion 被引量:6
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作者 LIU Tao FENG Mang WANG Ke-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期561-566,共6页
The quantum behavior ofa precooled cantilever can be probed highly efficiently by electrostatically coupling to a trapped ultracold ion, in which a fast cooling of the cantilever down to the ground vibrational state ... The quantum behavior ofa precooled cantilever can be probed highly efficiently by electrostatically coupling to a trapped ultracold ion, in which a fast cooling of the cantilever down to the ground vibrational state is possible. Within a simple model with an ultracold ion coupled to a cantilever with only few vibrational quanta, we solve the dynamics of the coupling system by a squeezed-state expansion technique, and can in principle obtain the exact solution of the time-evolution of the coupling system in the absence of the rotating-wave approximation. Comparing to the treatment under the rotating-wave approximation, we present a more accurate description of the quantum behavior of the cantilever. 展开更多
关键词 ultracold ion CANTILEVER squeezed-state
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Immunological response in alcoholic liver disease 被引量:9
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作者 Michael J Duryee Lynell W Klassen Geoffrey M Thiele 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第37期4938-4946,共9页
The development of alcoholic liver disease (ALD) can be attributed to many factors that cause damage to the liver and alter its functions. Data collected over the last 30 years strongly suggests that an immune compone... The development of alcoholic liver disease (ALD) can be attributed to many factors that cause damage to the liver and alter its functions. Data collected over the last 30 years strongly suggests that an immune component may be involved in the onset of this disease. This is best evidenced by the detection of circulating autoantibodies, infiltration of immune cells in the liver, and the detection of hepatic aldehyde modified proteins in patients with ALD. Experimentally, there are numerous immune responses that occur when proteins are modified with the metabolites of ethanol. These products are formed in response to the high oxidative state of the liver during ethanol metabolism, causing the release of many inflammatory processes and potential of necrosis or apoptosis of liver cells. Should cellular proteins become modified with these reactive alcohol metabolites and be recognized by the immune system, then immune responses may be initiated. Therefore, it was the purpose of this article to shed some insight into how the immune system is involved in the development and/or progression of ALD. 展开更多
关键词 Alcoholic liver disease Liver endothelial cells Aldehyde adducts Oxidative stress Immune system CYTOKINES METABOLISM
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Landscape change detection in Yulin prefecture 被引量:2
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作者 ZHANJinyan DENGXiangzheng YUETianxiang 《Journal of Geographical Sciences》 SCIE CSCD 2004年第1期47-55,共9页
Landscape is a dynamic phenomenon that almost continuously changes. The overall change of a landscape is the result of complex and interacting natural and spontaneous processes and planned actions by man. However, num... Landscape is a dynamic phenomenon that almost continuously changes. The overall change of a landscape is the result of complex and interacting natural and spontaneous processes and planned actions by man. However, numerous activities by a large number of individuals are not concerted and contribute to the autonomous evolution of the landscape in a similar way as natural processes do. There is a well-established need to detect land use and ecological change so that appropriate policies for the regional sustainable development can be developed. Landscape change detection is considered to be effectively repeated surveillance and needs especially strict protocols to identify landscape change. This paper developed a series of technical frameworks on landscape detection based on Landsat Thematic Mapper (TM) Data. Through human-machine interactive interpretation, the interpretation precision was 92.00% in 1986 and 89.73% in 2000. Based on the interpretation results of TM images and taking Yulin prefecture as a case study area, the area of main landscape types was summarized respectively in 1986 and 2000. The landscape pattern changes in Yulin could be divided into ten types. 展开更多
关键词 LANDSCAPE remote sensing data Yulin prefecture
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Transient and etiology-related transcription regulation in cirrhosis prior to hepatocellular carcinoma occurrence 被引量:1
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作者 Frédérique Caillot Céline Derambure +6 位作者 Paulette Bioulac-Sage Arnaud Franois Michel Scotte Odile Goria Martine Hiron Maryvonne Daveau Jean-Philippe Salier 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第3期300-309,共10页
AIM: To search for transcription dysregulation that could (1) differentiate hepatocellular carcinoma (HCC)-free from HCC-related cirrhosis (2) differentiate HCC-free cirrhosis related to HCV from that related t... AIM: To search for transcription dysregulation that could (1) differentiate hepatocellular carcinoma (HCC)-free from HCC-related cirrhosis (2) differentiate HCC-free cirrhosis related to HCV from that related to alcohol intake. METHODS: Using microarray analysis, we compared transcript levels in HCC-free cirrhosis (alcoholism: 7; hepatitis C: 7), HCC-associated cirrhosis (alcoholism: 10; hepatitis C: 10) and eight control livers. The identified transcripts were validated by qRT-PCR in an independent cohort of 45 samples (20 HCC-free cirrhosis; 15 HCC-associated cirrhosis and 10 control livers). We also confirmed our results by immunohistochemistry.RESULTS: In HCC-free livers, we identified 70transcripts which differentiated between alcoholicrelated-cirrhosis, HCV-related cirrhosis and control livers. They mainly corresponded to down-regulation. Dysregulation of Signal Transduction and Activator of Transcription-3 (STAT-3) was found along with related changes in STAT-3 targets which occurred in an etiology-dependent fashion in HCC-free cirrhosis. In contrast, in HCC, such transcription dysregulations were not observed. CONCLUSION: We report that transcriptional dysregulations exist in HCC-free cirrhosis, are transiently observed prior to detectable HCC onset and may be appear like markers from cirrhosis to HCC transition. 展开更多
关键词 Liver PATHOLOGY ALCOHOLISM Hepatitis Cvirus Gene expression CARCINOGENESIS
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Repeated morphine treatment influences operant and spatial learning differentially 被引量:4
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作者 Mei-Na WANG Zhi-Fang DONG +1 位作者 Jun CAO Lin XU 《Neuroscience Bulletin》 SCIE CAS CSCD 2006年第3期137-143,共7页
Objective To investigate whether repeated morphine exposure or prolonged withdrawal could influence operant and spatial learning differentially. Methods Animals were chronically treated with morphine or subjected to m... Objective To investigate whether repeated morphine exposure or prolonged withdrawal could influence operant and spatial learning differentially. Methods Animals were chronically treated with morphine or subjected to morphine withdrawal. Then, they were subjected to two kinds of learning: operant conditioning and spatial learning. Results The acquisition of both simple appetitive and cued operant learning was impaired after repeated morphine treatment. Withdrawal for 5 weeks alleviated the impairments. Single morphine exposure disrupted the retrieval of operant memory but had no effect on rats after 5-week withdrawal. Contrarily, neither chronic morphine exposure nor 5-week withdrawal influenced spatial learning task of the Morris water maze. Nevertheless, the retrieval of spatial memory was impaired by repeated morphine exposure but not by 5-week withdrawal. Conclusion These observations suggest that repeated morphine exposure can influence different types of learning at different aspects, implicating that the formation of opiate addiction may usurp memory mechanisms differentially. 展开更多
关键词 MORPHINE ADDICTION WITHDRAWAL CONDITIONING spatial learning
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An Improved Nonlinear Dynamic Inversion Method for Altitude and Attitude Control of Nano Quad-Rotors under Persistent Uncertainties 被引量:1
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作者 Chen Meili Wang Yuan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第3期483-493,共11页
Nonlinear dynamic inversion(NDI)has been applied to the control law design of quad-rotors mainly thanks to its good robustness and simplicity of parameter tuning.However,the weakness of relying on accurate model great... Nonlinear dynamic inversion(NDI)has been applied to the control law design of quad-rotors mainly thanks to its good robustness and simplicity of parameter tuning.However,the weakness of relying on accurate model greatly restrains its application on quad-rotors,especially nano quad-rotors(NQRs).NQRs are easy to be influenced by uncertainties such as model uncertainties(mainly from complicated aerodynamic interferences,strong coupling in roll-pitch-yaw channels and inaccurate aerodynamic prediction of rotors)and external uncertainties(mainly from winds or gusts),particularly persistent ones.Therefore,developing accurate model for altitude and attitude control of NQRs is difficult.To solve this problem,in this paper,an improved nonlinear dynamic inversion(INDI)method is developed,which can reject the above-mentioned uncertainties by estimating them and then counteracting in real time using linear extended state observer(LESO).Comparison with the traditional NDI(TNDI)method was carried out numerically,and the results show that,in coping with persistent uncertainties,the INDI-based method presents significant superiority. 展开更多
关键词 nonlinear dynamic inversion extended state observer nano quad-rotor uncertainties rejection altitude control attitude control
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Morphological analysis of the Chinese Cipangopaludina species(Gastropoda; Caenogastropoda: Viviparidae) 被引量:1
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作者 Hong-Fa LU Li-Na DU +2 位作者 Zhi-Qiang LI Xiao-Yong CHEN Jun-Xing YANG 《Zoological Research》 CAS CSCD 北大核心 2014年第6期510-527,共18页
Viviparidae are widely distributed around the globe, but there are considerable gaps in the taxonomic record. To date, 18 species of the viviparid genus Cipangopaludina have been recorded in China, but there is substa... Viviparidae are widely distributed around the globe, but there are considerable gaps in the taxonomic record. To date, 18 species of the viviparid genus Cipangopaludina have been recorded in China, but there is substantial disagreement on the validity of this taxonomy. In this study, we described the shell and internal traits of these species to better discuss the validity of related species. We found that C. ampulliformis is synonym of C. lecythis, and C. wingatei is synonym of C. chinensis, while C. ampullacea and C. fluminalis are subspecies of C. lecythis and C. chinensis, respectively. C. dianchiensis should be paled in the genus Margarya, while C. menglaensis and C. yunnanensis belong to genus Mekongia. Totally, this leaves 11 species and 2 subspecies recorded in China. Based on whether these specimens' spiral whorl depth was longer than aperture depth, these species or subspecies can be further divided into two groups, viz. chinensis group and cathayensis group, which can be determined from one another via the ratio of spiral depth and aperture depth, vas deferens and number of secondary branches of vas deferens. Additionally, Principal Component Analysis indicated that body whorl depth, shell width, aperture width and aperture length were main variables during species of Cipangopaludina. A key to all valid Chinese Cipangopaludina species were given. 展开更多
关键词 Cipangopaludina GASTROPODA Bellamyinae ANATOMY TAXONOMY CHINESE
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