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Climate and land-use change in wetlands:a dedication

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Ecosystem Health and Sustainability 2017年第9期3卷 1-3页

作者： beth A.Middleton U.S.Geological Survey Wetland and Aquatic Research CenterLafayetteLAUSA

Future climate and land-use change may wreak havoc on wetlands,with the potential to erode their values as harbors for biota and providers of human *** are important to protect,particularly because these provide a var... 详细信息

关键词： harbor change climate

INVESTIGATION OF THE ATRP OF n-BUTYL METHACRYLATE USING THE Cu(I)/N,N,N',N",N"-PENTAMETHYLDIETHYLENETRIAMINE CATALYST SYSTEM

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Chinese Journal of Polymer Science 2004年第2期22卷 195-204页

作者： kelly A. Davis Krzysztof Matyjaszewski Center for Macromolecular Engineering Department of Chemistry Carnegie Mellon University 4400 Fifth Ave.Pittsburgh Pennsylvania 15213 USACenter for Macromolecular Engineering Department of Chemistry Carnegie Mellon University 4400 Fifth Ave.Pittsburgh Pennsylvania 15213 USA

The polymerization of n-butyl methacrylate was investigated using the Atom Transfer Radical Polymerization technique with CuBr and CuCl/N,N,N',N',N'-pentamethyldiethylenetriamine catalytic systems. Various combinations of catalyst systems and initiators were utilized in order to optimize the polymerization conditions and to obtain well-defined polymers (i.e. controlled molecular weights and low polydispersities). It has been found that the optimal initiator for this system is a chlorine-based initiator, when the catalyst used is a salt in conjunction with the N,N,N',N',N'- pentamethyldiethylenetriamine ligand. Bromine-based initiators tend to result in large amounts of initial termination, leading to polymers with less than ideal chain end functionality, even if CuCl is used as the species to invoke the halogen exchange. Additionally, the effects of the polymerization temperature, species and the initiator structure were determined.

关键词： ATRP Atom transfer radical polymerization Controlled/living radical polymerization Butyl methacrylate Pentamethyldiethylenetriamine

Optimization designed large-stroke MEMS micromirror for adaptive optics

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Chinese Optics Letters 2010年第12期8卷 1163-1166页

作者：孙全 kelly He Edmond Cretu College of Optoelectronics Science and Engineering National University of Defense Technology Department of Electrical and Computer Engineering University of British Columbia

A novel micromirror based on the PolyMUMPs process is designed and presented. The hexagonal micromirror with a diameter of 450 μm consists of three supporting bilayer cantilevers and a mirror plate. The bilayer cantilevers, formed with a polysilicon layer and a gold layer, elevate the mirror plate according to residual stress-induced bending. Both analytical and finite element analysis （FEA） models are built to calculate the elevated height of the free end of the cantilever. The analytical solution is in accordance with the FEA simulation results, with longitudinal stresses applied only. Results of a three-dimensional （3D） simulation with two direction stresses applied also show the elevated height to be proportional to the width of the cantilever and the length of the gold layer. Due to the torque of the joint, the elevated heights of the two kinds of cantilevers assembled with the mirror plates are much smaller than those of the free end of the cantilevers. Both micromirrors with different cantilevers are fabricated. The elevated heights of the fabricated micromirrors are measured using Veeco optical profiler, which show good coincidence with simulation results.

关键词： Finite element method Microelectromechanical devices Mirrors Polysilicon Three dimensional Three dimensional computer graphics

The impact of increased flooding caused by climate change on heritage in England and North Wales, and possible preventative measures: what could/should be done?

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Built Heritage 2023年第1期7卷 44-58页

作者： kelly Anderson Independent Consultant ManchesterEngland

Despite 30 years of discussion,adaptation work is not routinely being carried out at heritage sites to minimise future impacts of climate change,particularly increased flooding *** understand barriers to essential work being carried out,interviews were carried out with six heritage sites that have already experienced river flooding to understand levels of preparation both before and after the flooding *** results prove that despite funding,or lack of,being an important contributor,it is not the sole barrier to *** flooded sites still do not have a flood plan in place,outside agencies are preventing work being carried out,measures which have been put in place through listing status are prohibiting necessary work and delays in decision making about what is acceptable are all delaying adaptation while allowing more damage to be caused from weather *** responsibility for adaptation lies locally this situation will not improve;responsibility needs to lie more *** the principle of replacing like for like is a sound one with the best of intentions behind it,this is also contributing to losses in heritage and must be reconsidered when big decisions are finally made about what will be acceptable if impacts to heritage from future climate change are to be minimised.

关键词： climate change adaptation barriers heritage flooding site interviews

Antibiotic use in early childhood and risk of obesity: longitudinal analysis of a national cohort

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World Journal of Pediatrics 2019年第4期15卷 390-397页

作者： Dervla kelly Alan kelly Tom O'Dowd Catherine B.Hayes Department of Public Health and Primary Care Trinity College DublinRussell CenterTallaght CrossDublin 24Ireland

Background Taking oral antibiotics during childhood has been linked with an increased risk of childhood *** study assessed any potential association in number of courses of antibiotics taken between 2-3 and 4-5 years of age and body mass trajectory up to age *** The study was a secondary analysis of 8186 children and their parents from the infant cohort of the Irish National Longitudinal Study of *** use was measured by parental recall between ages 2-3 and *** models described the relationship between antibiotic exposure and body mass index (BMI) standard deviation scores andbinary outcomes,and examined interactions between covariates,which included socioeconomic status,diet assessed by food frequency questionnaires and maternal *** Any antibiotic usage between 2 and 3 years did not predict risk of overweight or obesity at age *** or more courses of antibiotics between 2 and 3 years were independently associated with obesity at age 5 (odds ratio 1.6,95% confidence interval 1.11-2.31).Effect size was modest (coefficient + 0.09 body mass SD units,standard error 0.04,P =0.037).Maternal BMI modified the relationship:≥ 4 courses of antibiotics between 2 and 3 years were associated with a + 0.12 body mass SD units increase in weight at age 5 among children of normal-weight mothers (P=0.035),but not in children of overweight *** Number of antibiotic courses,rather than antibiotic use,may be an important factor in any link between early antibiotic exposure and subsequent childhood *** is needed to confirm differential effects on babies of normal versus overweight/obese mothers independent of socioeconomic factors.

关键词： Antibiotics Body mass index Early childhood Infants Obesity

Effects of water level alteration on carbon cycling in peatlands

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Ecosystem Health and Sustainability 2020年第1期6卷 199-227,198页

作者： Yehui Zhong Ming Jiang beth A.Middleton Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchunJilinPR China University of Chinese Academy of Sciences BeijingPR China Jilin Provincial Joint Key Laboratory of Changbai Mountain Wetland and Ecology ChangchunJilinPR China U.S.Geological Survey Wetlands and Aquatic Research CenterLafayetteLAUSA

Globally,peatlands play an important role in the carbon(C)*** water level is a key factor in maintaining C storage in peatlands,but water levels are vulnerable to climate change and anthropogenic *** review examines literature related to the effects of water level alteration on C cycling in peatlands to summarize new ideas and uncertainties emerging in this *** ecosystems maintain their function by altering plant community structure to adapt to changing water *** primary production,woody plants are more productive in unflooded,well-aerated conditions,while Sphagnum mosses are more productive in wetter *** responses of sedges to water level alteration are *** peat decomposition is faster in unflooded,well aerated conditions,increased plant production may counteract the C loss induced by increased ecosystem respiration(ER)for a period of *** contrast,rising water table maintains anaerobic conditions and enhances the role of the peatland as a C ***,changes in DOC flux during water level fluctuation is complicated and depends on the interactions of flooding with ***,vegetation also plays a role in C flux but particular species vary in their ability to sequester and transport *** ecosystems have a greater resilience to water level alteration than fens,due to differences in biogeochemical responses to *** full understanding of the role of peatlands in global C cycling deserves much more study due to uncertainties of vegetation feedbacks,peat-water interactions,microbial mediation of vegetation,wildfire,and functional responses after hydrologic restoration.

关键词： Peatlands carbon cycling climate change anthropogenic disturbance water level

Double aortic arch and nasogastric tubes: A fatal combination

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World Journal of Gastroenterology 2008年第16期14卷 2590-2592页

作者： Julia Massaad kelly Crawford Emory University School of Medicine Division of Digestive Diseases

Double aortic arch is a common form of complete vascular ring that encircles both the trachea and the esophagus, and presents with various respiratory and esophageal symptoms, usually in the pediatric population. We present a case of double aortic arch in an adult patient that manifested as massive upper gastrointestinal bleeding after prolonged nasogastric intubation.

关键词： Nasogastric tubes Aortoesophageal fistula Gastrointestinal bleeding Double aortic arch Vasculardngs

Multilayer network analyses as a toolkit for measuring social structure

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Current Zoology 2021年第1期67卷 81-99页

作者： kelly R.FINN Neukom Institute Dartmouth CollegeHanoverNH 03755USA

The formalization of multilayer networks allows for new ways to measure sociality in complex social systems,including groups of *** same mathematical representation and methods are widely applicable across fields and study systems,and a network can represent drastically different types of *** such,in order to apply analyses and interpret the results in a meaningful way the researcher must have a deep understanding of what their network is representing and what parts of it are being measured by a given *** social networks can represent social structure with more detail than is often present in single layer networks,including multiple"types"of individuals,interactions,or relationships,and the extent to which these types are *** networks can also encompass a wider range of social scales,which can help overcome complications that are inherent to measuring *** this paper,I dissect multilayer networks into the parts that correspond to different components of social structures.I then discuss common pitfalls to avoid across different stages of multilayer network analyses-some novel and some that always exist in social network analysis but are magnified in multi-layer *** paper serves as a primer for building a customized toolkit of multilayer network analyses,to probe components of social structure in animal social systems.

关键词： animal behavior multilayer networks relationships sociality social networks social structure subgroups

Broken connections of wetland cultural knowledge

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Ecosystem Health and Sustainability 2016年第7期2卷 1-3页

作者： beth A.Middleton U.S.Geological Survey Wetland and Aquatic Research Center700 Cajundome BoulevardLafayetteLouisiana 70506 USA

As global agriculture intensifies,cultural knowledge of wetland utilization has eroded as natural resources become more stressed,and marginal farmers move away from the *** excellent paper by Fawzi et al.(2016)documents a particularly poignant case of traditional knowledge loss among the Marsh Arab women of *** interviews,the authors document the breakdown of skill transfer from the older to younger generation of *** authors link the loss of their cultural knowledge with the loss of wetlands in the *** can no longer provide support for their families using wetland products,and along with that,their ancient knowledge of plant usage is *** ancient skills included medicinal uses,and reed harvesting for both weaving and water buffalo ***,the majority of the Mesopotamian Marshes have dried,this way of life is being forgotten(Fawzi et al.2016).The global tragedy is that while the careful alliance of wetlands and people have sustained human cultures for millennia,degraded wetlands lose their ability to provide these services(Maltby 1986).

关键词： younger sustained wetland