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Network coding-aware cache replacement policy in on-demand broadcast environments

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Journal of Harbin Institute of Technology(New Series) 2012年第5期19卷 92-100页

作者：陈君 lee Victor C S CHAN edward School of Information Management Wuhan UniversityWuhan 430072China Dept.of Computer Science City University of Hong KongHong KongChina

Network coding has been proved to be an effective technique in improving the performance of data broadcast systems because clients requesting different data items can be served simultaneously in one broadcast. Previous studies showed that its efficiency is highly related to the content of clients' cache. However, existing data broadcast systems do not take network coding information into account when making cache replacement decisions. In this paper, we propose two networks coding-aware cache replacement policies called DLRU and DLRU-CP to supplement network coding assisted data broadcast in on-demand broadcast environments. In DLRU, both data access and decoding contribution are taken into account to make replacement decisions. DLRU-CP is based on DLRU but allows clients to retrieve decodable data items that have not been requested yet. The performance gain of our proposed cache replacement policies over traditional cache replacement policy is shown in the simulation results, which demonstrate conclusively that the proposed policies can effectively reduce the overall response time.

关键词： Network coding cache replacement on-demand broadcast mobile computing

Trace metals and animal health: Interplay of the gut microbiota with iron, manganese, zinc, and copper

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Animal Nutrition 2021年第3期7卷 750-761页

作者： edward Alain B.Pajarillo Eunsook lee Dae-Kyung Kang Department of Pharmacy and Pharmaceutical Sciences Florida A&M UniversityTallahassee 32307FLUSA Department of Animal Resources Science Dankook UniversityCheonan 31116Republic of Korea

Metals such as iron,manganese,copper,and zinc are recognized as essential trace *** trace metals play critical roles in development,growth,and metabolism,participating in various metabolic processes by acting as cofactors of enzymes or providing structural support to *** or toxicity of these metals can impact human and animal health,giving rise to a number of metabolic and neurological *** breakdown,absorption,and elimination of these trace metals is a tightly regulated process that requires crosstalk between the host and these *** gut is a complex system that serves as the interface between these components,but other factors that contribute to this delicate interaction are not well *** gut is home to trillions of microorganisms and microbial genes(the gut microbiome)that can regulate the metabolism and transport of micronutrients and contribute to the bioavailability of trace metals through their assimilation from food sources or by competing with the ***,deficiency or toxicity of these metals can modulate the gut microenvironment,including microbiota,nutrient availability,stress,and ***,understanding the role of the gut microbiota in the metabolism of manganese,iron,copper,and zinc,as well as in heavy metal deficiencies and toxicities,and vice versa,may provide insight into developing improved or alternative therapeutic strategies to address emerging health *** review describes the current understanding of how the gut microbiome and trace metals interact and affect host health,particularly in pigs.

关键词： Gut microbiota Microbiome Iron Manganese Zinc Copper

Rapid climate change-induced collapse of hunter-gatherer societies in the lower Mississippi River valley between ca. 3300 and 2780 cal yr BP

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Science China Earth Sciences 2018年第2期61卷 178-189页

作者： tristram r.kidder edward r.henry lee j.arco Department of Anthropology Washington University in St. Louis St. Louis 63130 USA Geoarehaeology Laboratory Washington University in St. Louis St. Louis 63130 USA GAI Consultants Inc. Homestead PA 15120 USA Teaching and Experimental Center for Archaeology and Cultural Heritage Protection Henan University Kaifeng 475001 China

Hunter-gatherer communities in the American Southeast reached an apogee of social and political complexity in the period between ca. 4200 and 3000 cal yr BP. In the lower Mississippi Valley(LMV) the Poverty Point culture defined this period of socio-political elaboration. However, following a significant period of climate change that led to exceptional flooding and a major reorganization of the course of the Mississippi River, this culture collapsed beginning ca. 3300–3200 cal yr BP and the LMV was abandoned for the subsequent 500 years. In this study, we use data from the Jaketown site in the Yazoo Basin of west-central Mississippi to refine the chronology of the climate event that caused the collapse of the Poverty Point culture. A large flood buried Poverty Point-era occupation deposits at Jaketown around 3310 cal yr BP. Lateral migration of the Mississippi River during flooding led to inundation of the Yazoo Basin and re-occupation of ancient river courses. A coarse sand stratum topped by a more than a meter-thick fining upward sediment package marks a crevasse deposit caused by a rupture of the natural levee at Jaketown. This levee breach was part of a larger pattern of erratic flooding throughout the LMV and is associated with major landscape evolution and the abandonment of Poverty Point sites within the valley. Early Woodland peoples re-colonized the crevasse surface after ca. 2780 cal yr BP. Following this event, the Jaketown site and the eastern Yazoo Basin witnessed a period of landscape stability that lasts to this day. These archaeological data demonstrate how climate change and natural disasters can lead to socio-political dissolution and reorganization even in relatively small-scale hunter-gatherer populations.

关键词： Rapid climate change Hunter-gatherers Flooding Mississippi River Valley Poverty Point Jaketown site

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墙上的别样风景

现代装饰（家居） 2016年第3期 68-75页

作者： Alan Wisniewski àlvaro Goula&Pablo Figuera Anette Stabel David Quan Erika Kovesdi edward lee Filippo Mambretti Jordan Murphy Joel Yatscoff Moe Takemura Michelle Ivankovic Michelle Ivankovic&Laura Carwardine rebobdesign Sung Wook Park Wesley Chau 伏平范嘉苑

墙是一种象征,在远离文明的荒滩野漠,它会滋生家的联想;墙是一段历史,在纵横古今的变迁时代,它承载着一个王朝的盛哀;墙是一个屏障,在进退攻守的人际交往中,它是守护心灵的桥头堡;墙是一道风景,在四季轮回的辗转交织间,它呈现着大自然... 详细信息

墙是一种象征,在远离文明的荒滩野漠,它会滋生家的联想;墙是一段历史,在纵横古今的变迁时代,它承载着一个王朝的盛哀;墙是一个屏障,在进退攻守的人际交往中,它是守护心灵的桥头堡;墙是一道风景,在四季轮回的辗转交织间,它呈现着大自然的万般风情。如今,随着现代人对家居环境的要求日益提高,如何将家装扮得既有个性又富有内涵和独特的品味。

关键词：风景墙人际交往家居环境桥头堡大自然现代人承载

Isotope Geochemistry of Volcanic Rocks from the Barton Peninsula,King George Island,Antarctica

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Journal of Earth Science 2011年第1期22卷 40-51页

作者： Jeong Hwang 郑祥身 edward M Ripley Jong-Ik lee Dongbok Shin Department of Geological Engineering Daejeon University Institute of Geology and Geophysics Chinese Academy of Sciences Department of Geological Sciences Indiana University Korea Polar Research Institute Department of Geological Sciences Kongju University

C, O, H, S and Sr isotopes were investigated to characterize the isotopic composition of the Paleocene-Eocene volcanic rocks in Barton Peninsula, King George Island, Antarctica. The analyzed samples of volcanic rocks cover a range from basalt to andesite. The δ 13C and 61SO values of calcite in volcanic rocks range from -7.5‰ to -3.2‰ and 0.4‰ to 5.1‰, respectively. The homogenous δ 13C cal and depleted δ18 Ccal values relative to primary magmatic values reflect the effect of high temperature alteration of volcanic rocks. The δ18 O of volcanic rocks ranges from -1.1‰ to 7.2‰, and the majority of values are significantly lower than those of primary magmatic values. The low δ18 O WR values are compatible with high temperature alteration. The initial values of 87Sr/86Sr of volcanic rocks span a narrow range from 0.703 312 to 0.703 504 which belong to the present mid-oceanic ridge basalt. The values of 87Sr/86Sr of volcanics in the Barton Peninsula are similar to those determined in the Fildes Peninsula, King George Island. The δD WR and H2O contents of volcanic rocks range from -74‰ to -66‰ and 0.67 wt.% to 2.74 wt.%, respectively. The higher δD WR and H2O wt.% of volcanic rocks relative to fresh basalts also result from high temperature alteration. Sulfur isotope compositions of the volcanic rocks range from -12.5‰ to -7.0‰; these values may represent fractionation accompanying partial oxidation of magmatic S or incorporation of some bacteriogenic sulfide. The low S contents and negative correlation with C and H2O reflect the formation of calcite and breakdown of sulfide as a result of high temperature water-rock interaction.

关键词： isotope volcanic rock high temperature alteration Antarctica.

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坦诚

时代英语（高二版） 2018年第2期 8-8页

作者：罗伯特·爱德华·李

在世间必须学会以真诚示人，率真乃诚实与勇气之子。无论在何种场合，都应该道出自己的真实想法。如果朋友对你有所求，对于合情合理之请，应该欣然同意；不然，应该坦率地告诉他拒绝的理由。模棱两可的话会让别人产生误解，也会使自己... 详细信息

在世间必须学会以真诚示人，率真乃诚实与勇气之子。无论在何种场合，都应该道出自己的真实想法。如果朋友对你有所求，对于合情合理之请，应该欣然同意；不然，应该坦率地告诉他拒绝的理由。模棱两可的话会让别人产生误解，也会使自己蒙受冤屈。

关键词：坦诚勇气合情

Residential building performance analysis at near extreme weather conditions in Hong Kong through a thermal-comfort-based strategy

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Building Simulation 2023年第1期16卷 13-25页

作者： K.F.Fong C.K.lee Kevin Ka-Lun Lau edward Yan Yung Ng Division of Building Science and Technology College of EngineeringCity University of Hong KongHong KongChina Department of Civil Engineering and Natural Resources Lulea University of TechnologySweden School of Architecture The Chinese University of Hong KongHong KongChina

The precise building performance assessment of residential housings in subtropical regions is usually more difficult than that for the commercial premises due to the much more complicated behavior of the occupants with regard to the change in indoor *** conventional use of a fixed schedule for window opening,clothing insulation and cooling equipment operation cannot reflect the real situation when the occupants respond to the change in thermal comfort,thus affecting the appropriateness of the assessment *** rectify the situation,a new modeling strategy in which the modification of the various operation schedules was based on the calculated thermal comfort(TC),was developed in this *** this new TC-based strategy,the realistic building performances under different cooling provision scenarios applied to a high-rise residential building under the near extreme weather conditions were investigated and *** was found that sole provision of ventilation fans could not meet the zone thermal comfort by over 68%of the time,and air-conditioning was *** optimal use of ventilation fans for cooling could only help reduce the total cooling energy demand by less than 12%at best which could only be realistically evaluated by adopting the present *** studies were conducted which revealed that some design factors could offer opportunities for reducing the total cooling energy under the near extreme weather conditions.

关键词： predicted mean vote thermal comfort ventilation potential building performance simulation residential housings

Mini-Review:Green sustainable processes using supercritical fluid carbon dioxide

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Journal of Environmental Sciences 2009年第6期21卷 720-726页

作者： RAMSEY edward University of Science and Technology Liaoning

Environmentally benign carbon dioxide offers significant potential in its supercritical fluid phase to replace current reliance on a range of hazardous, relatively expensive and environmentally damaging organic solvents that are used on an extensive global basis. The unique combination of the physical properties of supercritical fluids are being exploited and further researched to continue the development and establishment of high efficiency, compact plant to provide energy and water efficient manufacturing processes. This mini-review is focused on the use and potential applications of supercritical fluid carbon dioxide for a selected range of key and emerging industrial processes as a sustainable alternative to totally eliminate or greatly reduce the requirement of numerous conventional organic solvents. Examples of the industries include： chemical extraction and purification, synthetic chemical reactions including polymerization and inorganic catalytic processes. Biochemical reactions involving enzymes, particle size engineering, textile dyeing and advanced material manufacture provide further illustrations of vital industrial activities where supercritical fluid technology processes are being implemented or developed. Some aspects relating to the economics of sustainable supercritical fluid carbon dioxide processes are also considered.

关键词： supercritical extraction synthesis catalysis enzymes polymerization particles dyeing

Vitamin B6 and colorectal cancer:Current evidence and future directions

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World Journal of Gastroenterology 2013年第7期19卷 1005-1010页

作者： Xue-Hong Zhang Jing Ma Stephanie A Smith-Warner Jung Eun lee edward Giovannucci Channing Division of Network Medicine Department of MedicineBrigham and Women's Hospital and Harvard Medical SchoolBostonMA 02115United States Department of Nutrition and Department of EpidemiologyHarvard School of Public HealthBostonMA 02115United States Department of Food and Nutrition Sookmyung Women's UniversitySeoul 140742South Korea

Colorectal cancer remains the third most common cancer in both women and men *** modifiable dietary factors is crucial in developing primary prevention *** B6 is involved in more than 100 coenzyme reactions,and may influence colorectal cancer risk in multiple ways including through its role in one-carbon metabolism related DNA synthesis and methylation and by reducing inflammation,cell proliferation,and oxidative *** studies of dietary or dietary plus supplementary intake of vitamin B6 and colorectal cancer risk have been inconsistent with most studies reporting nonsignificant positive or inverse ***,published studies of plasma pyridoxal 5'-phosphate(the active form of vitamin B6) levels consistently support an approximately 30%-50% reduction in risk of colorectal cancer comparing high with low *** reasons for the discrepancy in the results between dietary-based and plasma-based studies remain *** unresolved questions include the effects of vitamin B6 intake in early life(i.e.,childhood or adolescence) and of suboptimal vitamin B6 status on colorectal cancer risk,whether the associations with vitamin B6 differ across molecular subtypes of colorectal cancer,and whether the vitamin B6-colorectal cancer association is modified by genetic variants of one-carbon metabolism.

关键词： Vitamin B6 Plasma pyridoxal 5’-phosphate Colorectal cancer Adenoma Incidence Case-control study Cohort study Randomized controlled trial Epidemiology