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Climate Reconstruction based on Pollen Analysis in Inner Mongolia, North China from 51.9 to 30.6 kaBP

Acta Geologica Sinica(English Edition) 2013年第5期87卷 1444-1459页

作者： LI Suping david k.FERGUSON WANG Yong LI Jinfeng YAO Jianxin key Laboratory of Stratigraphy and Palaeontology Institute of Geology Chinese Academy of Geological Sciences Institute of Palaeontology University of Vienna State key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of Sciences

The palynomorph assemblage of lake sediments younger than 51.9 kaBP from Wulagai Gobi in Inner Mongolia was analyzed to reconstruct the vegetation and climate. From 51.9 to 30.6 kaBP, the vegetation was arid to semi-arid grassland with only slight changes. According to the palynomorphs, trees and shrubs were very rare. The large number and diversity of algae indicate the presence of a lake. Quantitative climatic conditions were reconstructed using the Best Analogues Method. The results indicate that the annual mean temperature was higher than that at present. The combination of temperature and annual precipitation suggests a change in the climate from cool dry to warm dry and then cool humid. Our results show that the annual precipitation values were mostly higher than that at present but were lower than 400 mm. It infers that the study area was already within the arid to semi-arid regions but with a stronger influence of the summer monsoon during 51.9 to 30.6 kaBP than at present. With slight differences mainly in time scale, the changing trend of the annual temperature curve is consistent with the other climatic records from Antarctica, Greenland, Hulu Cave （East China）, and the Tibetan Plateau during the last glacial period. From 30.6 kaBP to present, very few palynomorphs were detected in the samples. Hence, no information about the vegetation and climate could be extracted. Combined with other studies during Late Pleistocene, we presume that the reason for the lack of pollen during this period was caused by an abrupt temperature fall after 30.6 kaBP or that the lacustrine conditions were unsuitable for pollen deposition. It was probably incurred by the oxidation on land prior to deposition. But for those samples only with algae, it might be caused by the fact that algae could finish their life history in a very short time in a seasonal lake.

关键词： paleoclimate paleovegetation pollen analysis Late Pleistocene Inner Mongolia

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Studies on the cytocompatibility,mechanical and antimicrobial properties of 3D printed poly(methyl methacrylate)beads

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Bioactive Materials 2018年第2期3卷 157-166页

作者： david k.Mills Uday Jammalamadaka karthik Tappa Jeffery Weisman Center for Biomedical Engineering and Rehabilitation Science USA The School of Biological Sciences Louisiana Tech UniversityRustonLA 71272USA

Osteomyelitis is typically a bacterial infection(usually from Staphylococcus)or,more rarely,a fungal infection of the *** can occur in any bone in the body,but it most often affects the long bones(leg and arm),vertebral(spine),and bones of the *** success in osteomyelitis is due to their ability to form biofilms which inhibit the wound healing process and increases resistance to anti-infective ***,biofilms do not allow easy penetration of antibiotics into their matrix making clinical treatment a *** development of local antibiotic delivery systems that deliver high concentrations of antibiotics to the affected site is an emerging area of research with great *** treatment includes antibiotic therapy,either locally or systemically and refractory cases of osteomyelitis may lead to surgical intervention and a prolonged course of antibiotic treatment involving placement of antibiotic-doped beads or spacers within the wound *** are disadvantages with this treatment modality including insufficient mixing of the antibiotic,lack of uniform bead size,resulting in lower antibiotic availability,and limitations on the antibiotics ***,a method is needed to address biofilm formations in the wound and on the surface of the surgical implants to prevent *** this study,we show that all antibiotics studied were successfully doped into PMMA and antibiotic-doped 3D printed beads,disks,and filaments were easily *** growth inhibition capacity of the antibiotic-loaded PMMA 3D printed constructs was also demonstrated.

关键词： 3D printing Antibacterials Drug delivery Halloysite nanotubes Medical devices Nanotechnology

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An evaluation of the role played by remote sensing technology following the World Trade Center attack

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Earthquake Engineering and Engineering Vibration 2003年第1期2卷 159-168页

作者： Charles k.Huyck Beverley J.Adams david I.kehrlein ImageCat Inc.400 OceangateSuite 1050Long BeachCA90802USA Senior Vice President ImageCat Inc.400 OceangateSuite 1050Long BeachCA90802USA Project Scientist ImageCat Inc.6047 Woodhaven AvenueCarmichaelCA95608USA Vice PresidentGIS Operations

Remote sensing technology has been widely recognized for contributing to emergency response efforts after the World Trade Center attack on September 11th, 2001. The need to coordinate activities in the midst of a dense, yet relatively small area, made the combination of imagery and mapped data strategically useful. This paper reviews the role played by aerial photography, satellite imagery, and LIDAR data at Ground Zero. It examines how emergency managers utilized these datasets, and identifies significant problems that were encountered. It goes on to explore additional ways in which imagery could have been used, while presenting recommendations for more effective use in future disasters and Homeland Security applications. To plan adequately for future events, it was important to capture knowledge from individuals who responded to the World Trade Center attack. In recognition, interviews with key emergency management and geographic information system (GIS) personnel provide the basis of this paper. Successful techniques should not be forgotten, or serious problems dismissed. Although widely used after September 11th, it is important to recognize that with better planning, remote sensing and GIS could have played an even greater role. Together with a data acquisition timeline, an expanded discussion of these issues is available in the MCEER/NSF report “Emergency Response in the Wake of the World Trade Center Attack; The Remote Sensing Perspective” (Huyck and Adams, 2002) keywords World Trade Center (WTC) - terrorism - emergency response - emergency management - ground zero - remote sensing - emergency operations - disasters - geographic information systems (GIS) - satellite imagery - synthetic aperture radar (SAR) - light detection and ranging imagery (LIDAR)

关键词： World Trade Center (WTC) terrorism emergency response emergency management ground zero remote sensing emergency operations disasters geographic information systems (GIS) satellite imagery synthetic aperture radar (SAR) light detection and ranging imagery (LIDAR)

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Quantitative analysis of ruminal methanogenic microbial populations in beef cattle divergent in phenotypic residual feed intake(RFI)offered contrasting diets

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Journal of Animal Science and Biotechnology 2014年第4期5卷 439-447页

作者： Ciara A Carberry david A kenny Alan k kelly Sinead M Waters Animal and Bioscience Research Department Animal and Grassland Research and Innovation CentreTeagascGrangeDunsanyCo.MeathIreland UCD School of Agriculture Food Science and Veterinary MedicineCollege of Life SciencesUniversity College DublinBelfieldDublin 4Ireland

Background：Methane（CH_4） emissions in cattle are an undesirable end product of rumen methanogenic fermentative activity as they are associated not only with negative environmental impacts but also with reduced host feed *** aim of this study was to quantify total and specific rumen microbial methanogenic populations in beef cattle divergently selected for residual feed intake（RFI） while offered（i） a low energy high forage（HF） diet followed by（ii） a high energy low forage（LF） *** fluid was collected from 14 high（H）and 14 low（L） RFI animals across both dietary *** real time PCR（qRT-PCR） analysis was conducted to quantify the abundance of total and specific rumen methanogenic *** correlation analysis was used to investigate the association between the relative abundance of methanogens and animal performance,rumen fermentation variables and diet ***：Abundance of methanogens,did not differ between RFI ***,relative abundance of total and specific methanogen species was affected（P〈 0.05） by diet type,with greater abundance observed while animals were offered the LF compared to the HF ***：These findings suggest that differences in abundance of specific rumen methanogen species may not contribute to variation in CH_4 emissions between efficient and inefficient animals,however dietary manipulation can influence the abundance of total and specific methanogen species.

关键词： Bovine qRT-PCR Residual feed intake Rumen methaongens

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Bioactivity guided isolation of mosquito larvicide from Piper longum

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Asian Pacific Journal of Tropical Medicine 2011年第2期4卷 112-116页

作者： Madhu.S kumar Vijayan va Shaukath Ak Vector Biology Research Lab Department of Studies in ZoologyUniversity of MysoreManasagangotriMysore 570 006KarnatakaIndia Department of Studies in Zoology University of MysoreManasagangotriMysore 570 006KarnatakaIndia Department of Chemistry Yuvaraja's CollegeUniversity of MysoreMysore-05India

Objective:To isolate the larvicidal component from the fruits of Piper longum（***） against the filariasis vector,Culex quinquefasciatus（***）.Methods:Pulverized fruits of *** were subjected to soxhlet extraction using series of organic solvents of increasing *** the solvent extracts were verified for their larvicidal efficacy against 4th instar larvae of *** employing standard WHO *** fractionation through column chromatography lead to the isolation of a bioactive amide, pipyahyine from the petroleum ether ***:Petroleum ether extract was found to be the most active fraction among all the extracts tested with LC50 and LC90 being 1.03 and 2.04 ppm ***,pipyahyine,an isolated component of the same fraction was found to be even more effective than the parent extract in terms of LC50 being 0.58 and 1.88 ppm respectively. Conclusions:From the results,it is evident that *** can be considered as a powerful arsenal for the control of mosquito population.

关键词： Piper longum Bioassay Pipyahyine Culex quinquefasciatus Filariasis Larvicide

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Presentation, patterns and predictive value of baseline liver tests on outcomes in COVID-19 patients without chronic liver disease

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World Journal of Gastroenterology 2021年第42期27卷 7350-7361页

作者： david Bernstein Nitzan Roth Angela kim Marica Epstein david Hirschwerk Charlotte L kvasnovsky Sanjaya k Satapathy Department of Medicine/Hepatology Northwell HealthZucker School of Medicine at Hofstra/NorthwellManhassetNY 11030United States Division of Infectious Diseases Department of Medicine Northwell HealthZucker School of Medicine at Hofstra/NorthwellManhassetNY 11030United States Cohen Children's Medical Center Zucker School of Medicine at Hofstra/NorthwellNew Hyde ParkNY 11042United States

BACkGROUND Coronavirus disease 2019(COVID-19)infection is known to cause abnormal hepatic *** long term consequences of such elevations are *** To assessed the prevalence and prognostic value of initial liver enzymes in a large cohort of COVID-19 *** We reviewed electronic medical records of 10614 COVID-19 patients without known chronic liver disease who were admitted to our health system from March 1,2020,to April 30,*** analyzed baseline demographics and liver *** primary outcome was in-hospital mortality,and the secondary outcome was a composite of in-hospital mortality or need for mechanical *** Subjects with abnormal liver tests had increased risks of mortality and composite outcome when compared to patients with normal measurements on unadjusted analysis and after adjustment for demographic *** In our diverse patient population,liver enzyme abnormalities are associated with increased mortality and the need for mechanical ventilation in subjects without chronic liver *** patients are at the greatest risk for poor outcomes.

关键词： COVID-19 Liver enzymes Outcomes Predictors

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Phytochemical overview and medicinal importance of Coffea species from the past until now

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Asian Pacific Journal of Tropical Medicine 2016年第12期9卷 1101-1110页

作者： éva Brigitta Patay Tímea Bencsik Nóra Papp Department of Pharmacognosy Faculty of PharmacyUniversity of Pécs

Coffea(coffee) species are grown in almost all countries along the Equator. Many members of the genus have a large production history and an important role both in the global market and researches. Seeds(Coffeae semen) are successfully used in food, cosmetic, and pharmaceutical industries due to its caffeine and high polyphenol content. Nowadays, the three best-known coffee species are Arabic(Coffea arabica L.), Robusta(Coffea robusta L. Linden), and Liberian coffees(Coffea liberica Hier.). Even though, many records are available on coffee in scientific literature, wild coffee species like Bengal coffee(Coffea benghalensis Roxb. Ex Schult.) could offer many new opportunities and challenges for phytochemical and medical studies. In this comprehensive summary, we focused on the ethnomedicinal, phytochemical, and medical significance of coffee species up to the present.

关键词： Phytochemistry Medicinal importance Caffeine Polyphenols

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Near-Wall Flow in the Blade Cascades Representing Last Rotor Root Sections of Large Output Steam Turbines

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Journal of Thermal Science 2021年第1期30卷 220-230页

作者： ŠIMURDA david FÜRST Jiří HÁLA Jindřich LUXA Martin BOBČÍk Marek NOVÁk Ondřej SYNÁČJaroslav Institute of Thermomechanics of the Czech Academy of Sciences Prague 18200Czech Republic Dpt.of Technical Mathematics Faculty of Mechanical EngineeringCTU in PraguePrague 12000Czech Republic Doosan Skoda Power Pilsen 30100Czech Republic

This paper investigates the flow past two variants of root section profile cascades for a last stage rotor considering three-dimensional flow structures in the near-wall *** were drawn based on RANS numerical simulations of both variants and on the experimental data obtained by the 3 D traversing in the exit flow field of one of the *** of 3 D structures at two different regimes and its influence on aerodynamic characteristics of the blade cascades was *** distributions of Mach number along the profiles were compared with 2 D optical measurements and its distortion due to the presence of the sidewall was *** interaction between main vortical structures was described and its influence on the loading of the blades,mechanical energy losses and exit flow angle was *** results showed that for a front loaded blade the vortical structures appeared earlier and at a larger extent than for an aft loaded ***,due to different Mach number distribution,contribution of end wall flow to the energy losses was lower in the case of the aft loaded *** influence of the near wall flow on the loading was found to be rather weak while the deviation of the exit flow angle appeared to be comparable for both of the variants.

关键词： turbine blade cascade secondary flow near wall flow supersonic flow CFD experiment

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电力市场中的投标策略

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电力系统自动化 2000年第14期24卷 1-6页

作者：文福拴 A.k.david 浙江大学电力经济与信息化研究所杭州310027 香港理工大学电机系

在电力市场环境下 ,发电公司可通过采用策略性的投标来取得最大利润。另一方面 ,市场调节或监管机构 (regulator)需要评估发电公司的策略性投标行为 ,考察滥用市场力 (market power)的可能性 ,以确定适当的市场结构和管理规则 ,确保市... 详细信息

在电力市场环境下 ,发电公司可通过采用策略性的投标来取得最大利润。另一方面 ,市场调节或监管机构 (regulator)需要评估发电公司的策略性投标行为 ,考察滥用市场力 (market power)的可能性 ,以确定适当的市场结构和管理规则 ,确保市场竞争。这样 ,研究最优的投标策略是发电公司和市场调节机构都感兴趣的课题。近几年中 ,这方面的研究工作相当活跃 ,发表了数十篇论文。文中对这一领域的研究工作进行简要的综述。

关键词：电力市场投标策略市场力寡头垄断电力工业

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A system for probing Casimir energy corrections to the condensation energy

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Microsystems & Nanoengineering 2020年第1期6卷 1-12页

作者： Diego Perez-Morelo Alexander Stange Richard W.Lally Lawrence k.Barrett Matthias Imboden Abhishek Som david k.Campbell Vladimir A.Aksyuk david J.Bishop Department of ECE Boston UniversityBostonMA 02215USA Physical Measurement Laboratory National Institute of Standards and TechnologyGaithersburgMD 20899USA Institute for Research in Electronics and Applied Physics&Maryland NanoCenter University of MarylandCollege ParkMD 20742USA Division of MSE Boston UniversityBostonMA 02215 USA 54k-MEMS Sarl Rue des Lavannes 172072 St BlaiseSwitzerland Department of Physics Boston UniversityBostonMA 02215USA Department of ME Boston UniversityBostonMA 02215USA Department of BME Boston UniversityBostonMA 02215USA

In this article,we present a nanoelectromechanical system(NEMS)designed to detect changes in the Casimir *** Casimir effect is a result of the appearance of quantum fluctuations in an electromagnetic *** experiments have used nano-or microscale parallel plate capacitors to detect the Casimir force by measuring the small attractive force these fluctuations exert between the two *** this new set of experiments,we aim to directly detect the shifts in the Casimir energy in a vacuum due to the presence of the metallic parallel plates,one of which is a superconductor.A change in the Casimir energy of this configuration is predicted to shift the superconducting transition temperature(T_(c))because of the interaction between it and the superconducting condensation *** our experiment,we take a superconducting film,carefully measure its transition temperature,bring a conducting plate close to the film,create a Casimir cavity,and then measure the transition temperature *** expected shifts are smaller than the normal shifts one sees in cycling superconducting films to cryogenic temperatures,so using a NEMS resonator in situ is the only practical way to obtain accurate,reproducible *** a thin Pb film and opposing Au surface,we observe no shift in T_(c)>12µk down to a minimum spacing of~70 nm at zero applied magnetic field.

关键词： cycling energy film

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