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“果然”与“■”的语义对比
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作者 李光华 《汉语学习》 CSSCI 北大核心 2021年第5期85-93,共9页
本文对比分析现代汉语"果然"和与之相应的韩国语汉字词"■"。研究发现,二者都表示"事实与所说或所料相符",但还有很多不同之处。可以说,二者在各自的语言系统中有着不同的发展路径。前者的语义逐渐缩小,... 本文对比分析现代汉语"果然"和与之相应的韩国语汉字词"■"。研究发现,二者都表示"事实与所说或所料相符",但还有很多不同之处。可以说,二者在各自的语言系统中有着不同的发展路径。前者的语义逐渐缩小,而后者的语义基本保持不变并有所发展,导致前者语义单一、后者语义丰富,形成严重不平衡的格局。然而,韩国语"■"丰富的语义并非凭空而来,大部分可以在汉语发展史上找到其根源。 展开更多
关键词 果然 “■” 语义 预期 对比
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“X不然”的词汇构式化及其形成机制
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作者 李思旭 《安庆师范大学学报(社会科学版)》 2024年第4期120-128,共9页
构词图式“X不然”包含“要不然、果不然、终不然、再不然、若不然、纵不然”6个词语,对其中具有典型特征的“要不然、果不然、终不然”进行句法语义和历时来源的研究,尝试由点及面地揭示构词图式“X不然”的6个成员在固化程度、固化时... 构词图式“X不然”包含“要不然、果不然、终不然、再不然、若不然、纵不然”6个词语,对其中具有典型特征的“要不然、果不然、终不然”进行句法语义和历时来源的研究,尝试由点及面地揭示构词图式“X不然”的6个成员在固化程度、固化时间、形成机制、表义倾向、历时演变等方面的共性与差异。构式化包括语法构式化和词汇构式化,本文对汉语“X不然”的词汇构式化研究,希望能对国内外的构式化理论有所丰富和发展。 展开更多
关键词 “要不然” “果不然” 构词图式 形成机制 历时演变
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已然/未然范畴与“果真”的分化 被引量:1
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作者 聂仁发 葛子岚 《宁波大学学报(人文科学版)》 2019年第5期72-76,共5页
虚词词典要增强科学性与实用性,除了列举词义与举例说明外,更应指出制约义项与功能出现的语言条件。研究表明,"果真"源于"果然真的",其义项与功能同已然/未然范畴关系密切,各义项实际上是同一义位的不同变体:在已... 虚词词典要增强科学性与实用性,除了列举词义与举例说明外,更应指出制约义项与功能出现的语言条件。研究表明,"果真"源于"果然真的",其义项与功能同已然/未然范畴关系密切,各义项实际上是同一义位的不同变体:在已然语境中,"果真"相当于"果然";未然语境中,"果真"相当于"真的"。"果真"的分化为汉语存在已然/未然的对立提供了又一例证。 展开更多
关键词 已然/未然 虚词释义 “果真” 果然 “真的”
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汉语副词语义分析中的概率特征——以一组确认义副词的辨析为例 被引量:4
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作者 周韧 《汉语学报》 CSSCI 北大核心 2022年第3期2-18,共17页
本文将“概率”作为虚词分析中的一项语义特征,讨论现代汉语中一组确认义副词(包括“果然、真的、果真、确实、的确、实在”)在句法语义上的异同。文章先指出,“果然”用于说明已实现事件是事先认为具有高概率实现的事件;“真的”用于... 本文将“概率”作为虚词分析中的一项语义特征,讨论现代汉语中一组确认义副词(包括“果然、真的、果真、确实、的确、实在”)在句法语义上的异同。文章先指出,“果然”用于说明已实现事件是事先认为具有高概率实现的事件;“真的”用于说明已实现事件是事先认为只有低概率实现的事件;而由于叙述视角的波动,“果真”作为“果然真的”的缩合形式,对概率的高低不敏感。文章进而引入语义结构的概念,说明“果然、真的、果真”类副词与“确实、的确”类副词的差异。文章认为,“果然”类副词用于回应事件发生之前对事件实现可能性的概率判断,说明该事件的实现概率为0到1之间的取值;而“确实”类副词用于回应对事件真实性的真伪判断,对事件作概率上0或1的取值。文章还利用可能世界概念,简要说明了概率特征在语言研究中对单次事件的适用方式。最后,文章还说明副词“实在”主要表达“主观高程度的确认”的语义,它的使用与概率无关。 展开更多
关键词 概率 果然 真的 确实 语义结构
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Competition-density effect in plant populations 被引量:2
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作者 薛立 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期48-50,83,共3页
The competition-density effect of plant populations is of significance in theory and practice of forest management and has been studied for long time. The differences between the two reciprocal equations of the compet... The competition-density effect of plant populations is of significance in theory and practice of forest management and has been studied for long time. The differences between the two reciprocal equations of the competition-density effect in nonself-thinning populations and self-thinning populations were analyzed theoretically. This supplies a theoretical basis for analyzing the dynamics of forest populations and evaluating the effect of forest management. 展开更多
关键词 Competition-density effect Self-thinning population Nonself-thinning population
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The Integration and Sustainable Development of Chengdu-Chongqing Urban Agglomeration 被引量:2
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作者 Yang Jie Mao Hanying 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第3期3-10,共8页
Urban Agglomeration is an inevitable outcome of urbanization and industrialization, and a main form of urban development. Based on the analysis of urbanization and urban system situation, this paper will discuss the i... Urban Agglomeration is an inevitable outcome of urbanization and industrialization, and a main form of urban development. Based on the analysis of urbanization and urban system situation, this paper will discuss the integration of urban agglomeration development, using the urban area of Cheng (Chengdu)-Yu (Chongqing) Urban agglomeration (CYUA) as a case study. By means of industries, population and spatial integrations, the function, strength and competition of CYUA will be improved and this urban agglomeration will transit from a budding state to a growing and mature one in future. The sustainable development of CYUA will depend on countermeasures, such as accelerating industrialization and urbanization, building a traffic network and express roads, strengthening the ability of self-sufficiency, enlarging the ecological construction and environmental protection, and establishing the synergetic institution of cross districts. 展开更多
关键词 Cheng (Chengdu)-Yu (Chongqing) Urban Agglomeration (CYUA) INTEGRATION sustainable development
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Inhibition effect of natural killer T cells on transplantation hepatocellular carcinoma in mice 被引量:3
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作者 Fuxing Chen Hongdan Zhao Nanzheng Zhang Junquan Liu Zhonghai Zhou Leiqing Sun Yu Zhou 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第5期256-260,共5页
Objective:The aim of this study was to investigate the inhibition effect of natural killer T(NKT) cells on transplantation hepatocellular carcinoma in mice.Methods:α-galactosylceramide(α-GalCer)-pulsed DC and Hep S ... Objective:The aim of this study was to investigate the inhibition effect of natural killer T(NKT) cells on transplantation hepatocellular carcinoma in mice.Methods:α-galactosylceramide(α-GalCer)-pulsed DC and Hep S were prepared as stimulus.Hepatoma xenograft model was established and mice were randomly divided into 4 groups(n=13 each group):(1) control group,intravenous injection of the same volume of saline.(2) mature DC group,intravenous injection of mature DC cells(4×106 cells).(3) α-GalCer-pulsed HepS group,intravenous injection of α-GalCer-pulsed HepS(4×106 cells).(4) α-GalCer-pulsed mature DC group,intravenous injection of α-GalCer-pulsed DC(4×106 cells).The changes of tumor volume in mice and survival period were measured every 2 days.Percentage of NKT cells in spleens and cytotoxicity of spleen cells were detected by flow cytometry.Tumor tissues were analyzed by histopathological examination.Results:In α-GalCer-pulsed Heps and DC groups,the average survival period was prolonged and tumor volume was markedly decreased,spleen cells and NKT cells were significantly increased,and tumor necrosis was evident,compared to the control group.Conclusion:α-GalCer-pulsed DC and HepS could activate NKT cells in vivo,also increase NKT cells cytotoxicity,inhibit the growth of hepatomas and prolong survival period. 展开更多
关键词 liver neoplasms experimental α-galactosylceramide(α-GalCer) dendritic cells natural killer T(NKT) cells
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Analytical models for evaluating buoyancy-driven ventilation due to stack effect in a shaft considering heat transfer from shaft interior boundaries 被引量:1
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作者 阳东 李百战 +1 位作者 杜涛 李楠 《Journal of Central South University》 SCIE EI CAS 2012年第3期651-656,共6页
Stack effect is a dominant driving force for building natural ventilation.Analytical models were developed for the evaluation of stack effect in a shaft,accounting for the heat transfer from shaft interior boundaries.... Stack effect is a dominant driving force for building natural ventilation.Analytical models were developed for the evaluation of stack effect in a shaft,accounting for the heat transfer from shaft interior boundaries.Both the conditions with constant heat flux from boundaries to the airflow and the ones with constant boundary temperature were considered.The prediction capabilities of these analytical models were evaluated by using large eddy simulation(LES) for a hypothetical shaft.The results show that there are fairly good agreements between the predictions of the analytical models and the LES predictions in mass flow rate,vertical temperatures profile and pressure difference as well.Both the results of analytical models and LES show that the neutral plane could locate higher than one half of the shaft height when the upper opening area is identical with the lower opening area.Further,it is also shown that the analytical models perform better than KLOTE's model does in the mass flow rate prediction. 展开更多
关键词 stack effect theoretical analysis large eddy simulation vertical temperature distribution heat transfer
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Vertical Zonation of Horticultural Farming in the Alaknanda Basin of Garhwal Himalaya, India
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作者 Vishwambhar Prasad Sati 《Journal of Mountain Science》 SCIE CSCD 2005年第4期319-328,共10页
Horticultural practice in the Himalayas has great importance not only for economic development but also for environmental restoration. In the entire Himalayan mountain system, from Jammu and Kashmir Himalaya to Assam ... Horticultural practice in the Himalayas has great importance not only for economic development but also for environmental restoration. In the entire Himalayan mountain system, from Jammu and Kashmir Himalaya to Assam Himalaya, the practice of horticulture is centuries old, which includes varieties of fruits along with availability of high quality and quantity. In terms of the Alaknanda Basin, which is centrally located in the Himalayan system, the practice of horticulture does not get commercial level; only it is cultivated domestically. The climatic conditions ranging from sub-tropical (low-lying river valleys) to alpine and frigid (highly elevated regions) are suited for varieties of fruit cultivation, yet the benefit of this could not be utilized by the residents who are working in the agricultural fields. Besides, less proportion of land is devoted for fruit cultivation along with domestic production of fruits. The varieties of fruit cultivated in the basin range from mango-guava-papaya, stone-net, citrus to apple at the different elevations. Along with the cultivated fruits, varieties of wild fruits are also found in the jungle. There are four climatic zones suitable for the production of various fruits as below:? Sub-tropical zone including the lower part of the Alaknanda, Pindar, Nandakini, and Mandakini rivers is suitable for mango, guava, and papaya; ? Sub-temperate zone in the middle basin of the Alaknanda, Pindar, Nandakini and Mandakini rivers is a good place for citrus fruits, particularly orange and lemon; ? Temperate zone occupying the Dauli, Vishnu Ganga, Upper Pinder, Nandakini and Mandakini rivers is highly productive for apple, nut and stone fruits; ? Alpine meadows in the highly elevated region are known as Bugyal famous for herb culture. Each of these zones has distinct physical features, environmental conditions and socio-economic identity for fruit cultivation. The present paper aims to discuss about the vertical zonation of the horticultural farming and its nature, in terms of development, in the Alaknada Basin. 展开更多
关键词 Horticultural practice domestic production FRUIT herb culture wild fruit fruit production sustainable horticulture
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Influence of A-type Zeolite on Methane Hydrate Formation 被引量:8
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作者 臧小亚 杜建伟 +2 位作者 梁德青 樊栓狮 唐翠萍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期854-859,共6页
The porous medium has an important effect on hydrate formation.In this paper,the formation process and the gas storage capacity of the methane hydrate were investigated with A-type zeolite and Sodium Dodecyl Sulfate (... The porous medium has an important effect on hydrate formation.In this paper,the formation process and the gas storage capacity of the methane hydrate were investigated with A-type zeolite and Sodium Dodecyl Sulfate (SDS) existing in the system.The results show that A-type zeolite can influence methane hydrate formation.At the temperature of 273.5 K and pressure of 8.3 MPa,the distilled water with A-type zeolite can form methane hydrate with gaseous methane in 12 hours.The formation process of the system with A-type zeolite was quite steady and the amount of A-type zeolite can influence the gas storage capacity significantly.The adding of A-type zeolite with 0.067 g·(g water)-1 into 2×10-3 g·g-1 SDS-water solution can increase the gas storage capacity,and the maximum increase rate was 31%.Simultaneously the promotion effect on hydrate formation of 3A-type zeolite is much more obvious than that of 5A-type zeolite when the water adding amounts are 0.033 g·g-1 and 0.067 g·g-1 at the experimental conditions. 展开更多
关键词 HYDRATE FORMATION gas storage A-type zeolite
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Tourism versus nature conservation: reconciliation of common interests and objectives——an analysis through Picos de Europa National Park 被引量:4
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作者 LóPEZ Iván PARDO Mercedes 《Journal of Mountain Science》 SCIE CSCD 2018年第11期2505-2516,共12页
Nature tourism and particularly tourism in national parks have acquired significant importance in contemporary societies. Post-Fordist consumers have reevaluated the meanings of ‘nature' and ‘natural spaces'... Nature tourism and particularly tourism in national parks have acquired significant importance in contemporary societies. Post-Fordist consumers have reevaluated the meanings of ‘nature' and ‘natural spaces' and now avoid standardization to seek singularity. Tourism in national parks is a consequence of this tendency and has both positive and negative aspects. The purpose of this sociological research is to describe the most relevant conflicts in the Picos de Europa National Park(Spain) involving the park's conservation, local economic development,and tourism. Seven in-depth interviews and three focus groups were addressed to key local stakeholders.In this research were identified three chief areas of existing or potential inter-related conflicts and the main actors interacting with them. The first is on population, particularly, the negative consequences of depopulations on the local socio-economic development and the environment. A second source of conflicts identified is caused by the difficult conciliation between commercial exploitation and conservation of the protected natural area. More precisely, this specific form of tourism positively contributes to the economy of local communities whilst problems can arise for the conservation goals of National Parks. Thirdly, in this research is also analyzed the institutional governance and the inter and intra-governmental conflicts as well as with the Park's management body. These findings provide important information for the improved management of tourism and conflicting interests in natural parks. 展开更多
关键词 National parks Environmental conservation Nature tourism Mountain traditional economy Picos de Europa Spain
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Some Reflections of the Geographies of Socio-Economic Impact of the Kosi River Floods, 2008
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作者 Rituparna Bhattacharyya Muraree Lal Meena Suman Singh 《Journal of Earth Science and Engineering》 2013年第1期57-65,共9页
In India, floods remain a natural recurrent event of many major rivers of the sub-continent. Most frequently, it occurs during the "monsoon season" when precipitation remains very heavy and the natural watercourses ... In India, floods remain a natural recurrent event of many major rivers of the sub-continent. Most frequently, it occurs during the "monsoon season" when precipitation remains very heavy and the natural watercourses fail to accommodate excess water. The river Kosi, located in Bihar, India too bears a long history of annual floods and is often labeled as a "Sorrow of Bihar" due to its strange behavioural attributes and the extensive damage it causes as a result of severe flood inundation. The river Kosi is one of the megafans of the Gangetic plains. Geologic evidence demonstrates that the megafans are prone to devastating flood hazards. On August 18, 2008, the river Kosi burst through its banks to flow into a channel it had abandoned more than 200 years ago, drowning towns, numerous villages and rendering over a million homeless and many were reported to have died. The research is an attempt to reflect on the geographies of socio-economic impact of the Kosi flood, 2008. For this, the research uses a holistic approach. The findings suggest that the rescue and rehabilitation operation continue in the post flood region. However, operations were significantly delayed as the result of inept bureaucratic process and insufficient funding. The final sections draw together, the threads of analysis and suggest suitable measures, so that the floods of such magnitude can be managed better in near future. 展开更多
关键词 FLOOD river Kosi geographies of socio-economic impact holistic approach management.
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Effects of Different Live Food Extracts on Fish Attraction Activities 被引量:4
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作者 陈翔 沈钦一 +1 位作者 顾宪明 何川 《Agricultural Science & Technology》 CAS 2014年第6期942-946,963,共6页
[Objective] This study was to determine the effect of green biological feeds that little affected natural environment on fish attraction activities with the aim to explore new research direction for the recreational f... [Objective] This study was to determine the effect of green biological feeds that little affected natural environment on fish attraction activities with the aim to explore new research direction for the recreational fishing area. [Method] The ef- fective constituents of live natural foods, including chironomid larvae, earthworm, mussels, winkles, were separated by using soaking solution extraction and centrifu- gal extraction. The extracted live foods were used to attract the carp, young cru- cian, and fishes of 100-150 days old and over 1 year old, respectively. The feed nutrition formulation of the added food attractants was designed and applied to feed- ing in the aquaculture farm. The test results were practised in bait study to conduct field fishing test and collect the data. [Results] Compared with the control group, feeding with live foods had significantly improved the growth rates of fishes at dif- ferent ages, and greatly reduced food coefficients. [Conclusion] The feeds made from live food addictives had excellent attraction ability, which not only reduced the negative effects on natural environment but also made the aquaculture mode more organic and greener. 展开更多
关键词 Natural live food Attraction activity Amino acid Field fishing Feed nu-tritional formula
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Global Solution for Preserving Citrus Fruit Using Natural Treatments
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作者 Claudia Conesa Emesto Conesa 《Journal of Agricultural Science and Technology(A)》 2013年第7期503-510,共8页
Different tests were carried out to assess the efficiency of replacing plant protection products used at the main application points in citrus fruit packinghouses with natural treatments. The efficiency of an aqueous ... Different tests were carried out to assess the efficiency of replacing plant protection products used at the main application points in citrus fruit packinghouses with natural treatments. The efficiency of an aqueous treatment containing potassium sorbate was found to significantly reduce decaying in Marisol mandarins previously inoculated with Penicillium digitatum and Penicillium italicum. The same food preservative was used in conjunction with a fruit detergent and was applied on Washington Navel oranges and the reduction in the appearance of decaying was similar to that obtained using Guazatine. Finally, two different essential oils were tested. One was combined with a coating and the KS, whilst the other was applied as a fumigant. In the case of wax treatments, it was found that the combination of essential oil or KS with Imazalil at half the dose (0.1%) was equivalent to treatment with a higher dose of Imazalil (0.2%) thus making it possible to reduce the dose of plant protection products used without reducing decay control effectiveness. The treatment with a fumigant with essential oil has a level of efficiency similar to Imazalil against PI. These treatments can be considered a viable alternative to the use of plant protection products. 展开更多
关键词 POSTHARVEST DECAY citrus fruit potassium sorbate essential oils.
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Global Warming Some Perspectives
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作者 Anatoly D. Erlykin Arnold W. Wolfendale Edward Hanna 《Journal of Environmental Science and Engineering(B)》 2012年第4期499-509,共11页
Here the authors critically review the IPCC's claim that global warming is "very likely" caused by human activity: such a description underestimates the likelihood of the warming being due to this mechanism. Next ... Here the authors critically review the IPCC's claim that global warming is "very likely" caused by human activity: such a description underestimates the likelihood of the warming being due to this mechanism. Next examined are known alternative "natural" mechanisms which could give rise to the warming if, despite many claims, the man-made explanation was false because of compensation effects (greenhouse gases versus aerosol effects). Also, a number of difficulties, as yet unresolved, in the human-induced warming explanation are considered. 展开更多
关键词 Global warming CLIMATE CLOUDS AEROSOLS cosmic rays METEORITES volcanoes.
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Latidens salimalii (Endemic, Endanger Fruit Bat) A Reliable Propagator of Endemic Trees of Southern Western Ghats
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作者 Juliet Vanitharani 《Journal of Life Sciences》 2015年第9期423-435,共13页
Salim Ali's fruit bat (Latidens salimalii) is Endemic to Southern Western Ghats. India and is classified as Endangered by IUCN. Latidens is morphologically adapted to play a major role in the propagation of economi... Salim Ali's fruit bat (Latidens salimalii) is Endemic to Southern Western Ghats. India and is classified as Endangered by IUCN. Latidens is morphologically adapted to play a major role in the propagation of economically important trees: some of them are endemic to southern Western Ghats. This paper describes and documents, the bat"s ecology, foraging behavior and food selection. The study is based on the dietary details of the discovered populations of L. salimalii in the Agasthiyar hill range and the High Wavy Mountains of southern Western Ghats, India. Seeds. partially eaten fruits and seedlings germinated on the floor of the feeding roosts confirm this bat forage for fruits among relatively tall trees of evergreen forests in an elevation above 900 meter. Mist netting below and above canopy near the fruiting and flowering trees of their foraging area confirmed their interaction with certain endemic tree species. Their species specific dietars' preferences immensely help to restore and bring back the natural forest community structures. 展开更多
关键词 Endemic. foraging feeding roosts propagation restoration.
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Dynamic Effect of Rolling Massage on Blood Flow
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作者 CHEN Yan-Yan YI Hou-Hui +1 位作者 LI Hua-Bing FANG Hai-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期331-334,共4页
The Chinese traditional medical massage has been used as a natural therapy to eliminate some diseases. Here, the effect of the rolling massage frequency to the blood flow in the blood vessels under the rolling massage... The Chinese traditional medical massage has been used as a natural therapy to eliminate some diseases. Here, the effect of the rolling massage frequency to the blood flow in the blood vessels under the rolling massage manipulation is studied by the lattice Boltzmann simulation. The simulation results show that when the frequency is smaller than or comparable to the pulsatile frequency of the blood flow, the effect on the blood flux by the rolling massage is small. 011 the contrast, if the frequency is twice or more times of the pulsatile frequency of the blood flow, the blood flux is greatly enhanced and increases linearly with respect to the frequency. Similar behavior has also been observed on the shear stress on the blood vessel walls. The result is helpful for understanding that the rolling massage has the function of promoting the blood circulation and removing the blood stasis. 展开更多
关键词 rolling manipulation moving stenosed vessel wall shear stress LBM
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Low Complexity SOVA for Turbo Codes
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作者 Ruilin Pei Zulin Wang +1 位作者 Qin Huang Jiaqing Wang 《China Communications》 SCIE CSCD 2017年第8期33-40,共8页
Recently, trimming Soft-output Viterbi algorithm(T-SOVA) has been proposed to reduce the complexity of SOVA for Turbo codes. In its fi rst stage, a dynamic algorithm, lazy Viterbi algorithm, is used to indicate the mi... Recently, trimming Soft-output Viterbi algorithm(T-SOVA) has been proposed to reduce the complexity of SOVA for Turbo codes. In its fi rst stage, a dynamic algorithm, lazy Viterbi algorithm, is used to indicate the minimal metric differences which brings obstacle on hardware implementation. This paper proposes a Viterbi algorithm(VA) based T-SOVA to facilitate hardware implementation. In the first stage of our scheme, a modified VA with regular structure is used to fi nd the maximum likelihood(ML) path and calculate the metric differences. Further, local sorting is introduced to trim the metric differences, which reduces the complexity of trimming operation. Simulation results and complexity analysis show that VA based T-SOVA performs as well as lazy VA based T-SOVA and is easier to be applied to hardware implementation. 展开更多
关键词 VA SOVA local sorting hardware implementation
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Molecular docking study of xylogranatins binding to glycogen synthase kinase-3β
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作者 Christian Baillya Gérard Vergoten 《Digital Chinese Medicine》 2022年第1期9-17,共9页
Objective The mangrove tree Xylocarpus granatum J.Koenig(X.granatum)is a medicinal plant used to treat various diseases in several Asian countries.Many bioactive natural products have been isolated from the plants,par... Objective The mangrove tree Xylocarpus granatum J.Koenig(X.granatum)is a medicinal plant used to treat various diseases in several Asian countries.Many bioactive natural products have been isolated from the plants,particularly several groups of limonoids,including 18 xylogranatins(Xyl-A to R),all of which bear a furyl-δ-lactone core commonly found in limonoids.Based on a structural analogy with the limonoids obacunone and gedunin,we hypothesized that xylogranatins could target the enzyme glycogen synthase kinase-3β(GSK-3β),a major target for the treatment of neurodegenerative pathologies,viral infections,and cancers.Methods We investigated the binding of the 18 xylogranatins to GSK-3βusing molecular docking in comparison with two known reference GSK-3βATP-competitive inhibitors,LY2090314 and AR-A014418.For each compound bound to GSK-3β,the empirical energy of interaction(ΔE)was calculated and compared to that obtained with known GSK-3βinhibitors and limonoid triterpenes that target this enzyme.Results Five compounds were identified as potential GSK-3βbinders,Xyl-A,-C,-J,-N,and-O,for which the calculated empiricalΔE was equivalent to that calculated using the best reference molecule AR-A014418.The best ligand is Xyl-C,which is known to have marked anticancer properties.Binding of Xyl-C to the ATP-binding pocket of GSK-3βpositions the furyl-δ-lactone unit deep into the binding-site cavity.Other xylogranatin derivatives bearing a central pyridine ring or a compact polycyclic structure are much less adapted for GSK-3βbinding.Structure-binding relationships are discussed.Conclusion GSK-3βmay contribute to the anticancer effects of X.granatum extract.This study paves the way for the identification of other furyl-δ-lactone-containing limonoids as GSK-3βmodulators. 展开更多
关键词 Natural products Xylocarpus granatum Xylogranatins Glycogen synthase kinase-3β(GSK-3β) LIMONOIDS CANCER Molecular modelling Structure-activity relationship
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Validation of Monomeric Anthocianin Determination Method for Bilberry Juice and Marc Extracts
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作者 Ance Dandena Ieva Leimane Ugis Kletnieks 《Journal of Life Sciences》 2012年第12期1378-1382,共5页
The solid waste generated in industrial berry juice production was considered as a low cost raw material for the extraction of natural antioxidants. Berries contain phenolic compounds with high antioxidant potential, ... The solid waste generated in industrial berry juice production was considered as a low cost raw material for the extraction of natural antioxidants. Berries contain phenolic compounds with high antioxidant potential, including anthocianin. Quantitative determination method for monomeric anthocianins in bilberry juice and marc was validated. An official method from Association of Analytical Communities was used to determine anthocianins in juice and marc extracts by measuring light absorption for solutions with pH values 1.0 and 4.5 at 520 nm and 700 rim. Results were expressed as cyanidin-3-glucoside equivalent, as it is the most common anthocianin pigment. Calibration curve was obtained, linearity was checked, working interval and accuracy was determined and samples were tested. Mentioned method was evaluated as appropriate for quantitative anthocianin analysis in bilberry juice and marc. Necessity of calibration curve was approved using extinction coefficient of cyanidin-3-glucoside instead. Method assures adequate precision and accuracy as well. 展开更多
关键词 Natural antioxidants monomeric anthocianins bilberry juice bilberry marc.
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