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Stability of the Stratification of Water Bodies in the North Passage of the Yangtze River Estuary Based on the EFDC Model
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作者 WU De’an LI Xin WANG Yigang 《Journal of Ocean University of China》 CAS CSCD 2024年第1期23-32,共10页
To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC res... To study the stratified stability of a water column in the North Passage of the Yangtze River Estuary,a numerical model of the hydrodynamics of this estuary is established using the EFDC model.On the basis of EFDC results,this paper derives and pro-vides the discriminative index of water body stability caused by salinity and analyzes the along-range variation in water body strati-fication stability in the North Passage of the Yangtze River Estuary and the periodic variation at a key location(bend area)based on the simulation results of the numerical model.This work shows that the water body in the bend area varies between mixed and strati-fied types,and the vertical average flow velocity has a good negative correlation with the differential velocity between the surface and bottom layers of the water body.The model simulation results validate the formulae for the stratified stability discriminant during spring tides. 展开更多
关键词 Yangtze Estuary North Passage EFDC model stratification stability salinity distribution
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Logical stochastic resonance in a cross-bifurcation non-smooth system
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作者 张宇青 雷佑铭 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期659-667,共9页
This paper investigates logical stochastic resonance(LSR)in a cross-bifurcation non-smooth system driven by Gaussian colored noise.In this system,a bifurcation parameter triggers a transition between monostability,bis... This paper investigates logical stochastic resonance(LSR)in a cross-bifurcation non-smooth system driven by Gaussian colored noise.In this system,a bifurcation parameter triggers a transition between monostability,bistability and tristability.By using Novikov's theorem and the unified colored noise approximation method,the approximate Fokker-Planck equation is obtained.Then we derive the generalized potential function and the transition rates to analyze the LSR phenomenon using numerical simulations.We simulate the logic operation of the system in the bistable and tristable regions respectively.We assess the impact of Gaussian colored noise on the LSR and discover that the reliability of the logic response depends on the noise strength and the bifurcation parameter.Furthermore,it is found that the bistable region has a more extensive parameter range to produce reliable logic operation compared with the tristable region,since the tristable region is more sensitive to noise than the bistable one. 展开更多
关键词 logical stochastic resonance BIFURCATION mean first passage time
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Effects of high glucose and severe hypoxia on the biological behavior of mesenchymal stem cells at various passages
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作者 Fatimah Almahasneh Ejlal Abu-El-Rub +1 位作者 Ramada R Khasawneh Rawan Almazari 《World Journal of Stem Cells》 SCIE 2024年第4期434-443,共10页
BACKGROUND Mesenchymal stem cells(MSCs)have been extensively studied for therapeutic potential,due to their regenerative and immunomodulatory properties.Serial passage and stress factors may affect the biological char... BACKGROUND Mesenchymal stem cells(MSCs)have been extensively studied for therapeutic potential,due to their regenerative and immunomodulatory properties.Serial passage and stress factors may affect the biological characteristics of MSCs,but the details of these effects have not been recognized yet.AIM To investigate the effects of stress factors(high glucose and severe hypoxia)on the biological characteristics of MSCs at different passages,in order to optimize the therapeutic applications of MSCs.METHODS In this study,we investigated the impact of two stress conditions;severe hypoxia and high glucose on human adipose-tissue derived MSCs(hAD-MSCs)at passages 6(P6),P8,and P10.Proliferation,senescence and apoptosis were evaluated measuring WST-1,senescence-associated beta-galactosidase,and annexin V,respectively.RESULTS Cells at P6 showed decreased proliferation and increased apoptosis under conditions of high glucose and hypoxia compared to control,while the extent of senescence did not change significantly under stress conditions.At P8 hAD-MSCs cultured in stress conditions had a significant decrease in proliferation and apoptosis and a significant increase in senescence compared to counterpart cells at P6.Cells cultured in high glucose at P10 had lower proliferation and higher senescence than their counterparts in the previous passage,while no change in apoptosis was observed.On the other hand,MSCs cultured under hypoxia showed decreased senescence,increased apoptosis and no significant change in proliferation when compared to the same conditions at P8.CONCLUSION These results indicate that stress factors had distinct effects on the biological processes of MSCs at different passages,and suggest that senescence may be a protective mechanism for MSCs to survive under stress conditions at higher passage numbers. 展开更多
关键词 Mesenchymal stem cells High glucose HYPOXIA Stressful microenvironment Serial passage SENESCENCE APOPTOSIS
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旋转带肋通道流阻特性研究
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作者 由儒全 许云腾 李海旺 《风机技术》 2024年第2期51-61,共11页
With the development of aero-engines, the turbine inlet temperature continues to rise. In order to ensure the safety and reliability of the turbine blades, cooling structures must be set inside turbine blades to cool ... With the development of aero-engines, the turbine inlet temperature continues to rise. In order to ensure the safety and reliability of the turbine blades, cooling structures must be set inside turbine blades to cool them. Heat transfer coefficient and flow resistance are the key parameters to measure the cooling characteristics of internal cooling structures. In this paper, the characteristics of flow resistance in a rotating ribbed channel is presented numerical simulation under different rib spacings, rib angles, and thermal boundary conditions. The results show that, separation and reattachment of fluid between ribs is the key effect of rib spacing on flow resistance. The flow resistance is small when the rib spacing is small, because it's difficult for the fluid to form reattachment between the ribs. With the increase of rib spacing, the reattachment phenomenon is more obvious and the flow resistance increases accordingly. In general,p: e=10 channel has the maximum flow resistance. Secondary flow caused by the ribs is the key factor affecting the flow resistance characteristics with different rib angles. The secondary flow interacts with the main flow and causes flow loss through mixing, thus affecting the flow resistance of the channel. Under static condition, the flow resistance of 60°ribbed channel is the largest. The flow resistance of channel was affected by the temperature rise ratio also. And with the increase of the Ro, the temperature rise ratio has a more obvious effect on the flow resistance of the ribbed channel.When Ro=0.45, the flow resistance of the channel with a temperature rise ratio of 0.4 is 2.4 times that of the channel without temperature rise, while when Ro=0.3, it is 1.6 times, and when Ro=0.15, it is 1.2 times. 展开更多
关键词 Blade Cooling Ribbed Passage ROTATION Flow Resistance Characteristics
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Very early onset perinatal constipation:Can it be cow’s milk protein allergy?
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作者 Rajalakshmy Arakoni Hebat Kamal Sam Xianjun Cheng 《World Journal of Gastroenterology》 SCIE CAS 2023年第33期4920-4926,共7页
Delayed passage of meconium or constipation during the perinatal period is traditionally regarded as a signal to initiate further work up to evaluate for serious diagnoses such as Hirschsprung’s disease(HD),meconium ... Delayed passage of meconium or constipation during the perinatal period is traditionally regarded as a signal to initiate further work up to evaluate for serious diagnoses such as Hirschsprung’s disease(HD),meconium ileus due to Cystic Fibrosis,etc.The diagnosis of HD particularly warrants invasive testing to confirm the diagnosis,such as anorectal manometry or rectal suction biopsy.What if there was another etiology of perinatal constipation,that is far lesser known?Cow’s milk protein allergy(CMPA)is often diagnosed in infants within the first few weeks of life,however,there are studies that show that the CMPA allergen can be passed from mother to an infant in-utero,therefore allowing symptoms to show as early as day one of life.The presentation is more atypical,with perinatal constipation rather than with bloody stools,diarrhea,and vomiting.The diagnosis and management would be avoidance of cow's milk protein within the diet,with results and symptom improvement in patients immediately.Therefore,we discuss whether an alternative pathway to address perinatal constipation should be further discussed and implemented to potentially avoid invasive techniques in patients.This entails first ruling out CMPA with safe,noninvasive techniques with diet modification,and if unsuccessful,then moving forward with further diagnostic modalities. 展开更多
关键词 Delayed passage of meconium Perinatal constipation Cow's milk protein allergy IN-UTERO Alternate pathway Hirschsprung’s disease
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Development potential of the Northeast Passage based on a multinomial-logit-based stochastic user equilibrium model
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作者 ZHOU Xuelian HU Maixiu 《Advances in Polar Science》 CSCD 2023年第1期45-55,共11页
We developed a multinomial-logit-based stochastic user equilibrium(MNL SUE)model incorporating time value of cargo to investigate future proportions of cargo flow through the Northeast Passage(NEP)and the Suez Canal R... We developed a multinomial-logit-based stochastic user equilibrium(MNL SUE)model incorporating time value of cargo to investigate future proportions of cargo flow through the Northeast Passage(NEP)and the Suez Canal Route between representative ports.We studied navigation during the ice-free and ice-covered seasons using sea ice projections for 2070 based on 1991–2021 NEP ice data.Sailing distance and time between selected ports are lower via the NEP than the Suez Canal Route.Under the scenario of year-round operation of the NEP,the proportion of cargo flow through the NEP is estimated to be 68.5%,which represents considerable commercial potential.Proportions are higher for the ice-free season and for ports at high latitudes.We also assessed flow under different scenarios.Under the scenario of fuel price increase,proportion of flow through the NEP in the ice-covered season is expected to increase.If time value is ignored,flow through the NEP is expected to increase all year round.If shippers become more cost-conscious,flow through the NEP is also expected to increase. 展开更多
关键词 Northeast Passage multinomial-logit-based stochastic user equilibrium(MNL SUE) time value scenario analysis
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Network Pharmacology, Molecular Docking and Experimental Exploring Molecular Mechanisms of Yinqiao Anti-Epidemic Formula in Regulating Mucosal Immune System of Respiratory Tract
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作者 Heng XU Fangyuan LI +6 位作者 Guoqiang LIANG Jie YUAN Xiudao SONG Yunhai ZHOU Hui ZHU Yichao YAN Tingting WU 《Agricultural Biotechnology》 CAS 2023年第4期75-84,共10页
[Objectives]To explore the molecular mechanisms of Yinqiao anti-epidemic formula(YQAEF)in regulating mucosal immune system of respiratory tract.[Methods]The active components of YQAEF were obtained from the TCMSP data... [Objectives]To explore the molecular mechanisms of Yinqiao anti-epidemic formula(YQAEF)in regulating mucosal immune system of respiratory tract.[Methods]The active components of YQAEF were obtained from the TCMSP database,and RMIS targets were obtained from the GeneCards database.A"YQAEF components-RMIS targets-pathways"network was constructed by analyzing the above data to screen core targets for molecular docking verification.A mouse model of acute upper respiratory tract infection(AURI)was developed.Based on the experimental models,the key pathway target genes screened by network pharmacology were verified in vivo.[Results]The main active components of YQAEF involved in the regulation of the RMIS included quercetin,acetic acid,and raffinose.Key targets,such as angiotensin-converting enzyme(ACE),galactosidase alpha(GLA),matrix metalloproteinase 2(MMP2),Serpin Family E Member 1(SERPINE1),and myeloperoxidase(MPO)and important viral infection and endocrine resistance signaling pathways were included in the regulation of the RMIS with YQAEF.Molecular docking assays showed that the key targets had good binding activities with the components of YQAEF.Based on the results of network pharmacology,key target proteins in ACE,GLA,MMP2,SERPINE1,and MPO were selected for experimental verification.The results showed that ACE/ACE2 and MPO expressions were increased in the oral and throat mucosa of the AURI mice.Under YQAEF treatment,the expression levels of ACE/ACE2 and MPO were decreased.[Conclusions]This study revealed the mechanism of YQAEF in the regulation of RMIS,which is associated with multiple components,targets,and pathways.Further experiments confirmed that YQAEF interfered with MPO and ACE/ACE2 signaling pathways to regulate the RMIS in the oral and throat mucosa tissue of mice with AURI,and provide a new direction for exploring the potential antiviral mechanism of YQAEF. 展开更多
关键词 Respiratory passage mucosal immune system RMIS Network pharmacology Molecular docking ACE/ACE2 Yinqiao anti-epidemic formula(YQAEF)
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BRI:A Source of Growth Momentum
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作者 LIU XINLAN 《China Today》 2023年第10期46-48,共3页
TEN years ago,Chinese President Xi Jinping first proposed building the Silk Road Economic Belt while addressing the Nazarbayev University in Kazakhstan on September 7,2013.In the following decade,this proposal was tra... TEN years ago,Chinese President Xi Jinping first proposed building the Silk Road Economic Belt while addressing the Nazarbayev University in Kazakhstan on September 7,2013.In the following decade,this proposal was translated into action.The Belt and Road Initiative(BRI)took shape and expanded across the world,injecting new life into a millennia-old trade passage. 展开更多
关键词 expanded PASSAGE BRI
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拉萨绿化“汗骡功劳”
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作者 Tang Dashan Huang Wenjuan(译) 《China's Tibet》 2023年第1期48-55,共8页
Once the topic of transportation in Tibet,China’s highland plateau region,is brought up,one of two things often pops up in people’s minds,either the image of slowly moving caravans from the days of the ancient Tea-H... Once the topic of transportation in Tibet,China’s highland plateau region,is brought up,one of two things often pops up in people’s minds,either the image of slowly moving caravans from the days of the ancient Tea-Horse Road or the modern-day wonder of travel by air,car,and rail.With the swift passage of time. 展开更多
关键词 PASSAGE TRAVEL slowly
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Pathogenicity and amino acid sequences of hemagglutinin cleavage site and neuraminidase stalk of differently passaged H9N2-avian influenza virus in broilers 被引量:1
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作者 Houssam A. Shaib Nelly Cochet +4 位作者 Thierry Ribeiro Afif M. Abdel Nour Georges Nemer Maya F. Saade Elie K. Barbour 《Advances in Bioscience and Biotechnology》 2011年第4期198-206,共9页
Low pathogenic Avian Influenza (AI) virus has the ability to evolve to high pathogenic viruses resulting in significant economic losses in the poultry sector. This study aims at assessing the impact of H9N2 viral pass... Low pathogenic Avian Influenza (AI) virus has the ability to evolve to high pathogenic viruses resulting in significant economic losses in the poultry sector. This study aims at assessing the impact of H9N2 viral passaging in broilers and its relatedness to pathogenicity and amino acid (a.a) sequences of the hemagglutinin (HA) cleavage site and neuraminidase (NA) stalk. The original H9N2 AI virus (P0) was used to challenge ten-21 days old broilers. Individual recovery of H9N2 virus from homogenates of trachea, lungs and airsacs was attempted in 9 days old chicken embryos, as a conclusion of the first passage (P1). Tracheal isolates of H9N2 were passaged for a second (P2) and a third (P3) time in broilers, followed by a similar embryonic recovery procedure. The a.a. sequence of a part of HA1 cleavage site and Neuraminidase stalk were compared among the differently passaged viruses;an assessement of the relatedness of the determined a.a. sequences to the pathogenicity in broilers, based on frequency of mortality, morbidity signs, gross and microscopic lesions at 3 days post challenge with the P1, P2, and P3-H9N2, is concluded. An increase in certain morbidity signs and specific lesions was observed in P2- and P3-H9N2 challenged broilers compared to birds challenged with P1-H9N2. A conserved R-S-S-R amino acid sequence at the HA1 cleavage site was observed in the differently passaged H9N2, associated with a variability in the NA stalk-a.a sequences. The passaging of the low pathogenic H9N2 virus in broilers leads to a trend of increase in pathogenicity, manifested in higher frequency of morbidity signs, and of specific gross and microscopic lesions of the examined organs. This passaging was associated with a conserved a.a. sequence of the hemaglutinin cleavage site and a variability in the sequence of the neuraminidase stalk. A detailed study of the potential of the detected variability in the neuraminidase stalk of H9N2 in induction of a higher pathogenicity in broilers will be the subject of future investigations. 展开更多
关键词 H9N2 Avian Influenza PATHOGENICITY passaging BROILERS Amino Acid Sequences HEMAGGLUTININ (HA) NEURAMINIDASE (NA) STALK
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Increased osteogenesis with hydroxyapatite constructs combined with serially-passaged bone marrow-derived mesenchymal stem cells 被引量:1
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作者 Manabu Akahane Tomoyuki Ueha +5 位作者 Takamasa Shimizu Yusuke Inagaki Akira Kido Tomoaki Imamura Kenji Kawate Yasuhito Tanaka 《Stem Cell Discovery》 2012年第4期133-140,共8页
We have previously reported on both the osteogenic potential of hydroxyapatite (HA) combined with bone marrow-derived mesenchymal stem cells (BMSCs) and a method involving osteogenic matrix cell sheet transplantation ... We have previously reported on both the osteogenic potential of hydroxyapatite (HA) combined with bone marrow-derived mesenchymal stem cells (BMSCs) and a method involving osteogenic matrix cell sheet transplantation of BMSCs. In the present study, we assessed the osteogenic potential of serially-passaged BMSCs, both in vitro and in vivo. We also assessed whether an additional cell-loading technique can regain the osteogenic potential of the constructs combined with serially-passaged BMSCs. The present study revealed that passage (P) 1 cells cultured in osteogenic-induced medium showed strong positive staining for alkaline phosphatase (ALP) and Alizarin Red S, whereas P3 cells showed faint staining for ALP, with no Alizarin Red S staining. Staining of P1, P2 and P3 cells were progressively weaker, indicating that the osteogenic potential of the serially-passaged rat BMSCs is lost after P3 in vitro. The in vivo study showed that little bone formation was observed in the HA constructs seeded with P3 cells, 4 weeks after subcutaneous implantation. However, P3 cell/HA constructs which had increased cell-loading showed abundant bone formation within the pores of the HA construct. ALP and osteocalcin mRNA expression in these constructs was significantly higher than that of constructs with regular cell-seeding. The present study indicates that the osteogenic potential of the constructs with serially-passaged BMSCs is increased by additional cell-loading. This method can be applied to cases requiring hard tissue reconstruction, where BMSCs require serial expansion of cells. 展开更多
关键词 OSTEOGENESIS MESENCHYMAL Stem Cells SERIAL passaging HYDROXYAPATITE Tissue Engineering Bone Reconstruction
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Failure of Aspired Understanding Among the Human Race——On the Theme of A Passage to India
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作者 张晓霞 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S3期270-275,共6页
The author attempts to interpret the theme of A Passsage to India by analyzing the major events and characterization. It is indicated in the thesis that E.M.Forster highlights the failure of aspired understanding ... The author attempts to interpret the theme of A Passsage to India by analyzing the major events and characterization. It is indicated in the thesis that E.M.Forster highlights the failure of aspired understanding between different races, different people and even within a person. In other words, in many cases people have aspirations for understanding, but in reality the real understanding is very difficult to fulfill. 展开更多
关键词 I561.074 A PASSAGE to INDIA UNDERSTANDING MISUNDERSTANDING
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英语专业《综合英语2》模拟试题(1)(下)
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作者 祉音 《语言教育》 2002年第9期26-28,共3页
Ⅳ.阅读理解。认真阅读下面两篇短文,每篇短文后各有五个问题,根据短文的内容从A、 B、C、D四个选项中,选择一个正确答案。 (本大题共10小题,每小题1分,共1O分)Read the two passages and answer the questions.(10 points) Passage One... Ⅳ.阅读理解。认真阅读下面两篇短文,每篇短文后各有五个问题,根据短文的内容从A、 B、C、D四个选项中,选择一个正确答案。 (本大题共10小题,每小题1分,共1O分)Read the two passages and answer the questions.(10 points) Passage One Every artist knows in his heart that he is 展开更多
关键词 综合英语 英语专业 something 模拟试题 questions answer ARTIST passages PASSAGE SENTENCES
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英语专业《综合英语2》模拟试题(2)(下)
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作者 祉音 《语言教育》 2002年第11期28-30,共3页
IV.阅读理解。认真阅读下面两篇短文,每篇短文后各有五个问题,根据短文的内容从A、B、c、D四个选项中,选择一个正确答案。(本大题共10小题,每小题1分,共10分)Read the two passages and answer the questions. (10 points)Passage oneTh... IV.阅读理解。认真阅读下面两篇短文,每篇短文后各有五个问题,根据短文的内容从A、B、c、D四个选项中,选择一个正确答案。(本大题共10小题,每小题1分,共10分)Read the two passages and answer the questions. (10 points)Passage oneThe advantages and disadvantages of a large population has long been a subject of 展开更多
关键词 综合英语 英语专业 disadvantages discussion 模拟试题 questions ANSWER passages PASSAGE SENTENCES
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An Analysis of the Performance of Orientalism in A Passage to India and the Exorcization of Orientalism in Maxine Hong Kingston's Works
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作者 王雪莲 《英语广场(学术研究)》 2011年第Z4期24-25,共2页
This thesis tries to study two novels:firstly,the performance of Orientalism in the novel A Passage to India;secondly the Exorcization of Orientalism in the novel the Woman Warrior written by Maxine Hong Kingston.
关键词 ORIENTALISM A PASSAGE to INDIA Exorcization of ORIENTALISM the WOMAN Worrior
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英语专业本科毕业综合模拟试题(中)
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作者 杨俊峰 《语言教育》 2002年第12期24-28,共5页
Ⅲ.Reading Comprehension 20%Questions 1 -4 are based on the following passage.Are you a team person? Are you at your best as part of a small tightly united group of dedicated workers? If so, the future may hold more f... Ⅲ.Reading Comprehension 20%Questions 1 -4 are based on the following passage.Are you a team person? Are you at your best as part of a small tightly united group of dedicated workers? If so, the future may hold more for you than you think. 展开更多
关键词 英语专业 Questions Reading think 模拟试题 tightly PASSAGE UNITED nations LIKELY
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利用查读法找细节
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作者 明安云 《语言教育》 2001年第7期25-25,共1页
阅读可分为粗读和细读,或称快速阅读和精读。粗读又可分为略读(skimming)和查读(scanning)。略读就是迅速浏览文章以决定其要旨,即为了掌握一篇文章的大意和获取文章主要信息而进行的快速阅读,注意力主要放在情节和内容的发展上。
关键词 粗读 解题技巧 跳读 mentioned 通讯地址 疑问代词 特定信息 VISIBILITY PASSAGE 解题方法
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“桥”的故事
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作者 何苗 《中学生英语》 2016年第Z4期31-31,共1页
There are many expressions using the word"bridge".So today,let’s talk about the stories of"bridge".英语中有很多表达中使用了"桥"一词,所以今天我们就来说说"桥"的故事吧。A bridge i... There are many expressions using the word"bridge".So today,let’s talk about the stories of"bridge".英语中有很多表达中使用了"桥"一词,所以今天我们就来说说"桥"的故事吧。A bridge is a structure that provides passage over something—such as a river,train tracks,a highway or a deep,wide opening in the ground.The word"bridge"can also 展开更多
关键词 something today HIGHWAY river PASSAGE TRAIN WORRY CONVERSATION THINGS decide
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To Be or Not to Be:A Comparison between Two Novels
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作者 沈晓平 《海外英语》 2011年第5X期234-235,共2页
Both the two short novels The Short Happy Life of Francis Macombev by Hemingway and Barn Burning by Faulkner are well-known.Macomber and Sartoris are protagonists in these two novels respectively.Both of them were bet... Both the two short novels The Short Happy Life of Francis Macombev by Hemingway and Barn Burning by Faulkner are well-known.Macomber and Sartoris are protagonists in these two novels respectively.Both of them were betrayers to some one and to themselves;both of them had the important transformation in their life and grew mature.This article is making a comparison between these two novels from the perspective of rite of passage to explore their common theme:To Be is much more important than Not To Be,a life with self-determination and self-respect is much more significant than a life without self-judgment and dominated. 展开更多
关键词 macomber sartoris betrayer rite of PASSAGE
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阅读训练(33)(英文)
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作者 佘巧耘 《大学英语》 2014年第8期53-55,57,共4页
Passage One People who drink moderately,exercise,quit smoking and eat five servings of fruit and vegetables each day live an average 14 years longer than people who adopt 1 of these behaviors,according to a study by B... Passage One People who drink moderately,exercise,quit smoking and eat five servings of fruit and vegetables each day live an average 14 years longer than people who adopt 1 of these behaviors,according to a study by British researchers. 展开更多
关键词 moderately 阅读训练 VEGETABLES PASSAGE adopt EXERCISE DRINK SMOKING longer FRUIT
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