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Pollen Assemblage Features of Modern Water Samples from the Shiyang River Drainage, Arid Region of China

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Acta botanica Sinica 2002年第3期44卷 367-372页

作者：朱艳陈发虎程波张家武 David b.madsen 兰州大学西部环境教育部重点实验室西北师范大学地理与环境科学学院兰州730070 兰州大学干旱农业国家重点实验室兰州730000 Uath Geological Survey SaltLake CityUath 84114USA

Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and badain Jaran deserts, Northwest China was carried out to examine the river's capacity to carry pollen and spores, and to assess the contribution of the water-borne pollen to pollen assemblages in lake sediments at the end of the river system. Results indicate the pollen assemblages in water samples consist of both local and upland pollen. Percentages of upland pollen reach 30% - 60%, and pollen assemblages in water samples do not indicate the nature of local vegetation at the sampling sites. Fluvial currents have the capacity to transport large quantities of pollen long distances, and the contribution of this fluvial transported pollen is relatively high, For example, percentages of Picea Dietr. pollen in water samples at sampling sites 130 km and 145 km away from Picea forests reach 16.5% and 7.7%, respectively. Fluvial pollen transport occurs primarily during flood periods, and pollen concentrations from the flood samples are 17.1 - 12.5 times those from normal fluvial flow. Reservoirs affect pollen transportation since pollen is deposited at reservoir inlets and pollen concentrations are much reduced at reservoir outlets. Human activity can thus change natural features of pollen transportation and deposition. The main factors influencing pollen concentrations and assemblages are sampling time, sampling location, and rainfall intensity.

关键词： pollen analysis modern river water Shiyang River arid region of China

Antimicrobial silicone skin adhesives facilitated by controlled octenidine release from glycerol compartments

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International Journal of Smart and Nano Materials 2023年第3期14卷 369-389页

作者： V.Chiaula J.Jeppe madsen F.b.madsen P.Mazurek A.C.Nielsen A.L.Skov Danish Polymer Centre Department of Chemical and Biochemical EngineeringTechnical University of DenmarkLyngbyDenmark GRD Technology–Adhesives Coloplast A/SHumlebækDenmark

For improved wound healing,antimicrobial adhesives are one path ***,with the current challenge of bacterial resistance,it is essential to choose the included drug *** is an obvious choice due to its broad antimicrobial efficacy and no reported bacterial *** its pure form,octenidine complexes efficiently with the platinum catalyst in the silicone composition,inhibiting the targeted hydrosilyla-tion reaction and hindering *** obstacle is overcome by screening octenidine with cyclodextrins in homogeneously dispersed glycerol droplets,suppressing Pt inhibition in the silicone *** efficiency is demonstrated using rheol-ogy,which shows that it is possible to incorporate one wt%of octenidine into glycerol–silicone adhesives in the presence of(2-hydroxypropyl)-β-cyclodextrin without affecting the adhe-sives’mechanical *** interaction between octeni-dine and(2-hydroxypropyl)-β-cyclodextrin through an inclusion complex is confirmed by ROESY *** this screening,octenidine is still released efficiently from the glycerol–silicone adhesives upon contact with water,and the resulting antimicrobial action is subsequently *** new technology constitutes a simple and efficient method for preparing wound care adhesives that actively inhibit the growth of four bacteria strains and one fungus.

关键词： Silicone adhesive skin adhesive active adhesive antimicrobial

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卧螺离心机内部流动状态与沉降

过滤与分离 1996年第3期6卷 45-47页

作者： b.madsen 张剑鸣四川江北机械厂

卧螺离心机内部流动状态与沉降（丹）Ｂ．Ｍａｄｓｅｎ＊著四川江北机械厂张剑鸣译四川联合大学孙启才校卧螺离心机（图１）以连续方式将悬浮液分离成固相和液相，其分离过程通过高速旋转离心机转鼓实现。被分离出的固相（沉渣）由螺旋... 详细信息

卧螺离心机内部流动状态与沉降（丹）Ｂ．Ｍａｄｓｅｎ＊著四川江北机械厂张剑鸣译四川联合大学孙启才校卧螺离心机（图１）以连续方式将悬浮液分离成固相和液相，其分离过程通过高速旋转离心机转鼓实现。被分离出的固相（沉渣）由螺旋输送器输送到排渣口，螺旋输送器转速...

关键词：离心机卧螺离心机内部流动状态沉降

A mid-Holocene drought interval as evidenced by lake desiccation in the Alashan Plateau, Inner Mongolia, China

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Science bulletin 2003年第14期48卷 1401-1410页

作者： J.A.Holmes D.b.madsen C.G.Oviatt USA University College-London Desert Research Institute Department of Geography Environmental Change Research Center WC1H 0AP KS 66506 USA Correspondence should be addressed to Chen Fahu Department of Geology Reno Kansas State University London NV 89512 Division of Earth and Ecosystem Sciences Manhattan UK

The mid-Holocene in China is traditionally thought to be a warm and humid period with a strong summer monsoon, and is often termed the Holocene Climatic Optimum or Megathermal Period. Here we present lake geomorphologic and lithological evidence from the Alashan Plateau, part of the Mongolian Plateau, that indicates strong lake desiccation during the mid-Holocene. High resolution pollen data from Zhuyeze Lake, at the present summer monsoon margin, is also presented. These data show that present lakes and wetlands in the Juyanze Lake basin west of the badain Jaran desert, in the Zhuyeze Lake basin between the badain Jaran and Tengger deserts, and in lakes in the eastern Tengger desert, dried or experienced low lake levels in the mid-Holocene around 5000—7000 cal yr bP. Pollen data further indicate that the vegetation cover declined in both the local areas and in the Qilian Mountains, suggesting the climate was drier than that associated with the present Asian summer monsoon. This mid-Holocene drought interval was present throughout a quite large region of the south Inner Mongolian Plateau. The period was also probably colder, at least in the high Asian plateaus and mountains.

关键词： western Inner Mongolian Plateau mid-Holocene lake desiccation dry climate.

Computational Methods for Electromechanical Fields in Self-Assembled Quantum Dots

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Communications in Computational Physics 2012年第3期11卷 797-830页

作者： D.barettin S.madsen b.Lassen M.Willatzen Alsion 2 Mads Clausen InstituteUniversity of Southern DenmarkDK-6400 SønderborgDenmark

A detailed comparison of continuum and valence force field strain calculations in quantum-dot structures is presented with particular emphasis to boundary conditions,their implementation in the finite-elementmethod,and associated implications for electronic *** first part of this work provides the equation framework for the elastic continuum model including piezoelectric effects in crystal structures as well as detailing the Keating model equations used in the atomistic valence force field *** the variety of possible structure shapes,a choice of pyramidal,spherical and cubic-dot shapes is made having in mind their pronounced shape differences and practical *** this part boundary conditions are also considered;in particular the relevance of imposing different types of boundary conditions is highlighted and *** the final part,quantum dots with inhomogeneous indium concentration profiles are studied in order to highlight the importance of taking into account the exact In concentration profile for real quantum *** influence of strain,electric-field distributions,and material inhomogeneity of spherical quantum dots on electronic wavefunctions is briefly discussed.

关键词： Quantum dots electromechanical fields continuum model valence force field boundary conditions

Speculation on the timing and nature of Late Pleistocene hunter-gatherer colonization of the Tibetan Plateau

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Chinese Science bulletin 2003年第14期48卷 1510-1516页

作者： P.J.brantingham MAHaizhou J.W.Olsen GAOXinq D.b.madsen D.E.Rhode DepartmentofAnthropology UniversityofCaliforniaLosAngelesCA90095USA InstituteofSaltLakes ChineseAcademyofSciencesXining810008China DepartmentofAnthropology UniversityofArizonaAZ85721USA InstituteofVertebratePaleontologyandPaleoanthropology ChineseAcademyofSciencesBeiiing100044.China DesertResearchInstitute NV89512USA

Hunter-gatherer populations in greater northeast Asia experienced dramatic range expansions during the early Upper Paleolithic (45—22 ka) and the late Upper Paleolithic (18—10 ka), both of which led to intensive occupations of cold desert environments including the Mongolian Gobi and northwest China. Range contractions under the cold, arid extremes of the Last Glacial Maximum (LGM, 22—18 ka) may have entailed widespread population extirpations. The high elevation Qinghai-Tibetan Plateau is significantly more extreme in both climate and environment than either the Gobi or the Siberian taiga forests, and provides an ideal setting to test fundamental models of human biogeog- raphy in the context of regional population fluctuations. The area is presently occupied primarily by nomadic pastoralists, but it is clear that these complex middle Holocene (blished that Upper Paleolithic hunter-gatherers were present on the Qinghai-Tibetan Plateau by at least 12 ka and possibly much earlier. A speculative model for the colonization process is developed and preliminary archaeological data in support of the model are presented.

关键词：青藏高原晚更新世猎人聚集者定居时间自然环境人类地理学

Occupational risk of exposure to methicillin-resistant Staphylococcus aureus(MRSA)and the quality of infection hygiene in nursing homes

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Frontiers of Environmental Science & Engineering 2021年第3期15卷 111-121页

作者： Pil Uthaug Rasmussen Katrine Uhrbrand Mette Damkjaer bartels Helle Neustrup Dorina Gabriela Karottki Ute biiltmann Anne Mette madsen National Research Centre for the Working Environment Lerso Parkalle 1052100 Copenhagen 0Denmark Department of Clinical Microbiology Hvidovre HospitalKettegdrd Alle 302650 HvidovreDenmark The Danish Working Environment Authority Landskronagade 332100 CopenhagenDenmark University Medical Center Groningen Department of Health SciencesCommunity&Occupational MedicineUniversity of Groningen9700 GroningenThe Netherlands

Methicillin-resistant Staphylococcus aureus(MRSA)is an increasing health concern across the globe and is often prevalent at long-term care facilities,such as nursing ***,we know little of whether nursing home staff is exposed to MRSA via air and *** investigated whether staff members at nursing homes are colonised with and exposed to culturable MRSA,and assessed staff members'self-reported knowledge of MRSA and compliance with infection hygiene *** nursing homes with MRSA positive residents were visited in Copenhagen,*** bioaerosol exposure samples and environmental samples from surfaces,sedimented dust and bioaerosols were examined for MRSA and methicillin-suscqjtible ***(MSSA)to determine occupational *** were taken from staffs*nose,throat,and hands to determine whether they were colonised with *** online questionnaire about MRSA and infection control was *** staff members were colonised with MRSA,but MRSA was detected in the rooms of the colonised residents in two out of the five nursing *** was observed in air(n=4 out of 42,ranging from 2.9-1.9 CFU/m^(3)),sedimented dust(n=1 out of 58,1.1 ×10^(3) CFU/m^(2)/d),and on surfaces(n=9 out of 113,0.04-70.8 CFU/m^(2)).The questionnaire revealed that half of the staff members worry about spreading MRSA to *** aspects for improvement were improved availability and use of protective equipment,not transferring cleaning supplies(e.g.,vacuum cleaners)between residents'rooms and to reduce worry of MRSA,e.g.,through education.

关键词： Antibiotic resistance Airborne MRSA bioaerosols Healthcare-associated infections Healthcare worker Occupational health

An introduction to multivariate probabilistic forecast evaluation

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Energy and AI 2021年第2期4卷 119-135页

作者： Mathias blicher bjerregard Jan Kloppenborg Møller Henrik madsen Technical University of Denmark Department of Applied Mathematics and Computer Denmark

Probabilistic forecasting is becoming increasingly important for a wide range of applications,especially for en-ergy systems such as forecasting wind power production.A need for proper evaluation of probabilistic forecasts follows naturally with this,because evaluation is the key to improving the *** plenty of excellent reviews and research papers on probabilistic forecast evaluation already exist,we find that there is a need for an introduction with some practical *** particular,many forecast scenarios in energy systems are inher-ently multivariate,and while univariate evaluation methods are well understood and documented,only limited and scattered work has been done on their multivariate *** paper therefore contains a review of a selected set of probabilistic forecast evaluation methods,primarily scoring rules,as well as practical sections that explain how these methods can be calculated and *** three case studies featuring simple autore-gressive models,stochastic differential equations and real wind power data,we implement,apply and discuss the logarithmic score,the continuous ranked probability score and the variogram score for forecasting problems of varying ***,the advantages and disadvantages of the three scoring rules are highlighted,and this provides a significant step towards deciding on an evaluation method for a given multivariate forecast scenario including forecast scenarios relevant for energy systems.

关键词： Probabilistic forecast evaluation Multivariate scoring rules Wind power forecast Ensemble forecast Time series analysis

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晚第四纪青海湖高湖面研究

第四纪研究 2018年第5期38卷 1166-1178页

作者：刘向军赖忠平 David b. madsen 李国强于禄鹏黄昶陈发虎中国科学院青海盐湖研究所中国科学院盐湖资源综合高效利用重点实验室青海西宁810008 中国科学院青海盐湖研究所青海省盐湖地质与环境重点实验室青海西宁810008 中国地质大学(武汉)地球科学学院湖北武汉430074 兰州大学资源环境学院西部环境教育部重点实验室甘肃兰州730000 临沂大学资源与环境学院山东临沂276000 中国科学院青藏高原研究所北京100101

中国西北地区众多封闭湖泊湖岸堤的光释光（OSL）测年结果表明，＂大湖＂存在于深海氧同位素第5阶段（MIS 5）或者更早，而不是MIS 3阶段。由于高湖面测年结果的变化，我们对中国西北以及青藏高原地区湖泊对晚第四纪冰期-间冰期旋回气... 详细信息

中国西北地区众多封闭湖泊湖岸堤的光释光（OSL）测年结果表明，＂大湖＂存在于深海氧同位素第5阶段（MIS 5）或者更早，而不是MIS 3阶段。由于高湖面测年结果的变化，我们对中国西北以及青藏高原地区湖泊对晚第四纪冰期-间冰期旋回气候变化响应的认识也随之改变。本研究对青海湖周边的湖岸堤、湖相沉积物、冲积和风成沉积物进行光释光测年，重建了青海湖末次间冰期以来的高湖面演化历史，得到以下结论：1）最高湖面（拔湖26~66 m）出现在MIS 5时期；2） MIS 3c时期湖面高出现在约13~17 m，但是在MIS 3a阶段湖面下降至接近于中全新世湖面高度；3）全新世最高湖面出现在距今约5.1 ka，湖面至少高出现在9.1 m，之后在约2 ka前再一次出现高湖面，高出现在湖面约8 m。青海湖高湖面的拔湖高度从MIS 5a到MIS 3时期，再到全新世是依次降低的，使得早期的湖岸堤没有被后期高湖面破坏而较好的保存了下来。

关键词：青藏高原青海湖高湖面 OSL测年东亚夏季风