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Plant diversity and community structure of Brazilian Páramos

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Journal of Mountain Science 2018年第6期15卷 1186-1198页

作者： Prímula Viana CAMPOS Pedro Manuel VILLA Jaquelina Alves NUNES Carlos E.G.R.schaefer Stefan POREMBSKI Andreza Viana NERI Federal University of Vicosa Department of Plant Biology Laboratory of Ecology and Evolution of Plants Campus Universitdrio 36570-900 Vicosa Minas Gerais Brazil Foundation for the Conservation of Biodiversity 7101 Merida Venezuela Minas Gerais State University Rua dos estudantes 23 Santa Emilia 36800-000 Carangola Minas Gerais Brazil 4 Federal University of Vicosa Department of Soil Campus Universit（lrio 36570-900 Vicosa Minas Gerais Brazil 5 University of Rostock Institute of Bioseience Department of Botany Wismarsehe Str. 44/45 D-18051 Rostoek Germany

In Eastern South America, high altitude grasslands represent a mountain system that has a high number of endemic species. However, studies on the ecology of plant communities in these environments remain scarce. We aimed to evaluate the patterns of biodiversity and structure of plant communities from rocky outcrops in high altitude grasslands of three areas at the Caparaó National Park, southeastern Brazil, by sampling 300 randomly distributed plots. Then, we compared the floristic composition, relative abundance, and biological and vegetation spectra among areas. We classified species as endemic and non-endemic and verified the occurrence of endangered species. Species richness was evaluated by rarefaction analysis on the sampling units. The importance value and species abundance distribution(SAD) models were assessed. We also performed an indicator species analysis. We sampled 58 species belonging to 49 genera and 32 families. The number of species decreased with increasing altitude, with significant differences being observed among areas regarding richness, abundance, and cover. Of the total number of species, 10 are endemic to the Caparaó National Park and 17 are listed on the Brazilian Red List of endangered species. The dominant families on all peaks were Asteraceae and Poaceae. The SAD models showed lognormal and geometric distributions, corroborating the fact that 10 species that were common to all three areas were also the most dominant ones in the communities and showed the highest importance values, which ranged between 35% and 60%. Indicator species analysis revealed that 28 species(48.27%) were indicators. Of these, 42.85% had maximum specificity, meaning that they occurred only in one area. Thus, the number of species per life form ratio was similar among areas, yet vegetation spectra differed, especially for hemicryptophytes. The altimetric difference among the areas showed to be a very important driver in the community assembly, influencing the evalu

关键词： Rock outcrops High altitude grasslands Species abundance distribution Species richness

Pretreatment and enzymatic hydrolysis of sunflower hulls for fermentable sugar production

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International Journal of Agricultural and Biological Engineering 2012年第1期5卷 62-70页

作者： Sirinivas R.Kamireddy Christopher schaefer Matt Defrese John Degenstein Yun Ji Department of Chemical Engineering University of North DakotaGrand ForkND USA Department of Chemical and Materials Engineering California State Polytechnic University PomonaCalifornia USA Department of Chemical Engineering Purdue UniversityForney Hall of Chemical EngineeringWest LafayetteIN USA.

Sunflower is a widely adapted crop and can be grown in every temperature *** the U.S.,two million acres were cultivated with sunflowers in *** industrial processing,large quantities of hulls are obtained as a waste product from the dehulling *** study focused on converting the sunflower hulls into fermentable sugars by dilute acid pretreatment and enzymatic *** sunflower hulls are composed ofβ-glucan(34%±1.1%),lignin(25%±0.95%),xylan and arabinan(27%±1.56%),extractives(13%±2.5%)and traces of *** hulls were first subjected to pretreatment by varying three independent factors:1)acid concentration(0.5%-2%);2)reaction temperatures(140-160℃);3)reaction time(10-30 min).Slurry samples obtained after pretreatment were separated into liquid and solid *** fractions were analyzed for monomeric and oligomeric sugars and inhibitor products by High Pressure Liquid Chromatography(HPLC).Enzymatic saccharification was then performed on pretreated solid fractions to convert remaining cellulose(β-glucan)into fermentable *** results showed an increase in acid concentration and reaction temperature gave high xylose yield in the liquid ***,an increase in reaction time resulted in degradation of xylose into furfural.A quadratic model for xylose yield was formulated based on the experimental *** maximum xylose yield predicted by the model was 62%at 158℃for 20 min at 1.75%acid *** maximumβ-glucan digestibility of the enzymatic saccharification was 53.5%at 160℃for 30 min at 2%acid concentration.

关键词： sunflower hulls pretreatment central composite design enzymatic hydrolysis lignocellulosic ethanol biofuel

A road map to find in 3D printing a new design plasticity for construction e The state of art

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Frontiers of Architectural Research 2023年第2期12卷 337-360页

作者： João Teixeira Cecília Ogliari schaefer Bárbara Rangel Lino Maia Jorge Lino Alves CONSTRUCT Faculty of Engineering(FEUP)University of PortoPortoPortugal School of Arts Communication and HospitalityArchitecture and UrbanismUniversity of the ItajaíValleyItajaíBrazil Faculty of Architecture University of PortoPortoPortugal Faculty of Exact Sciences and Engineering University of MadeiraPortoPortugal INEGI/Faculty of Engineering University of Porto PortoPortugal

Recent years are showing a rapid adoption of digital manufacturing techniques to the construction industry,with a focus on additive *** 3D printing for construction(3DPC)has notably advanced in recent years,publications on the subject are recent and date a growth in 2019,indicating that it is a promising technology as it enables greater efficiency with fair consumption of material,minimization of waste generation,encouraging the construction industrialization and enhancing and accelerating the constructive *** new building system not only gives an optimization of the building process but provides a new approach to the building design *** direct connection between design and manufacturing allows the reduction in the number of the various construction phases *** is opening a new and wide range of options both formal and chromatic in customization,avoiding complex formworks,reducing costs and manufacturing *** creative process has a strict and direct link with the constructive process,straightening design with its ***-based materials lead the way,but new alternatives are being explored to further reduce its carbon *** order to leverage its sustainability and enhance the system capacity,initiatives are being pursued to allow the reduction of the use of *** are taking the first steps in *** and Demolition Waste(CDW)materials are used to substitute natural *** soil is being explored has a structural and aesthetic *** research trends are opening a wider range of possibilities for architecture and design,broadening the spectrum of color,texture,and formal *** concern about textures and colours is not yet evident in many the structures already printed,opening the opportunity for future *** can be done in the mixture and formal design of this building system,“discovering”other raw materials in others *** article aims to make a

关键词： 3D printing Architecture Construction Materials development Textures

A Scientometric Approach to Analyze Scientific Development on Renewable Energy Sources

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Journal of Data and Information Science 2021年第1期6卷 87-119页

作者： Jones Luís schaefer Julio Cezar Mairesse Siluk Ismael Cristofer Baierle Elpidio Oscar Benitez Nara Universidade Federal de Santa Maria Avenida Roraima1000Santa Maria 97105-900Brazil Universidade de Santa Cruz do Sul Avenida Independencia2293Santa CruzRS 96815-900Brazil

Purpose: This paper aims to point out the scientific development and research density of renewable energy sources such as photovoltaic, wind, and biomass, using a mix of computational tools. Based on this, it was possible to verify the existence of new research trends and opportunities in a macro view regarding management, performance evaluation, and decision-making in renewable energy generation systems and ***/methodology/approach: A scientometric approach was used based on a research protocol to retrieve papers from the Scopus database, and through four scientometric questions, to analyze each area. Software such as the Science Mapping Analysis Software Tool(Sci MAT) and Sci2 Tool were used to map the science development and ***: The scientific development of renewable energy areas is highlighted, pointing out research opportunities regarding management, studies on costs and investments, systemic diagnosis, and performance evaluation for decision-making in businesses in these *** limitations: This paper was limited to the articles indexed in the Scopus database and by the questions used to analyze the scientific development of renewable energy *** implications: The results show the need for a managerial perspective in businesses related to renewable energy sources at the managerial, technical, and operational levels, including performance evaluation, assertive decision making, and adequate use of technical and financial ***/value: This paper shows that there is a research field to be explored, with gaps to fill and further research to be carried out in this area. Besides, this paper can serve as a basis for other studies and research in other areas and domains.

关键词： Solar energy Photovoltaic energy Wind energy Biomass energy Scientometrics

微间隙受限液体行为与昆虫爪垫在光滑壁面的粘着机理

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物理学报 2007年第8期56卷 4722-4727页

作者：张晓昊张向军刘永和 J.A.schaefer 温诗铸清华大学摩擦学国家重点实验室 Department of Technical Physics Centre for Micro and NanotechnologiesTechnical University of IlmenauIlmenau98693Germany

自然界中许多昆虫通过分泌一层油性液体薄膜实现其爪垫表皮和光滑壁面之间粘附和解粘附,从而实现在光滑壁面上的快速爬行.为了揭示昆虫爪垫与光滑壁面间微量液体薄膜对生物粘着的意义,基于自行研制的粘着接触实验仪,采用微量的[emim][Tf... 详细信息

自然界中许多昆虫通过分泌一层油性液体薄膜实现其爪垫表皮和光滑壁面之间粘附和解粘附,从而实现在光滑壁面上的快速爬行.为了揭示昆虫爪垫与光滑壁面间微量液体薄膜对生物粘着的意义,基于自行研制的粘着接触实验仪,采用微量的[emim][Tf2N]离子液体和聚α烯烃油,观测其受限在纳米级光滑钢球表面与玻璃表面之间的接触行为以及法向粘着力.实验发现,临界体积(10-12—10-9L)范围内的受限液滴达到临界厚度(小于2μm)后会出现自动铺展和瞬时收缩行为,并同时提供幅值稳定且数值相当大的法向粘着力.这一现象与液桥弯月面的毛细作用有本质区别,受限液体薄膜表现出一定的类固化特征.基于这一现象,昆虫通过控制爪垫与壁面间受限液体的膜厚或液体量,就可以控制爪垫与光滑壁面粘着应力的大小(由0.45mPa减小到0mPa左右),从而实现稳固的粘附和快速的解粘附.微间隙受限液体的粘着行为研究可以为昆虫爪垫粘着机理及相关的仿生技术提供物理基础.

关键词：受限液体粘着力昆虫爪垫类固化

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Unlocking Potential

ChinAfrica 2013年第2期5卷 28-29页

作者： Hannah Edinger Simon schaefer Head of Research & Strategy at Frontier Advisory Senior Analyst at Frontier Advisory

IN December 2012, as corporate South Africa closed down for the holiday season, more than 4,500 members of the ruling African National Congress （ANC） descended on the city of Mangaung to elect their leadership for t... 详细信息

关键词： ANC Unlocking Potential

Outcome in neonates with necrotizing enterocolitis and patent ductus arteriosus

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世界儿科杂志:英文版 2016年第1期12卷 55-59页

作者： Ulf Kessler Franzisca Schulte Dietmar Cholewa Mathias Nelle Stephan C.schaefer Peter M.Klimek Steffen Berger Department of Pediatric Surgery InselspitalBern University Hospital and University of BernSwitzerland Division of Neonatology Department of PediatricsInselspitalBern University Hospital and University of BernSwitzerland Institute of Pathology InselspitalUniversity of BernBernSwitzerland Department of Surgery HFR Fribourg-Cantonal HospitalSwitzerland

Background:There is no agreement of the influence of patent ductus arteriosus(PDA)on outcomes in patients with necrotizing enterocolitis(NEC).In this study,we assessed the infl uence of PDA on NEC ***:A retrospective study of 131 infants with established NEC was ***(death,disease severity,need for surgery,hospitalization duration),as well as multiple clinical parameters were compared between NEC patients with no congenital heart disease(n=102)and those with isolated PDA(n=29).Univariate,multivariate and stepwise logistic regression analyses were ***:Birth weight and gestational age were significantly lower in patients with PDA[median(95%CI):1120 g(1009-1562 g),28.4 wk(27.8-30.5 wk)]than in those without PDA[median(95%CI):1580 g(1593-1905 g),32.4 wk(31.8-33.5 wk);P<0.05].The risk of NEC-attributable fatality was higher in NEC patients with PDA(35%)than in NEC patients without PDA(14%)[univariate odds ratio(OR)=3.3,95%CI:1.8-8.6,P<0.05;multivariate OR=2.4,95%CI:0.82-2.39,P=0.111].Significant independent predictors for nonsurvival within the entire cohort were advanced disease severity stage III(OR=27.9,95%CI:7.4-105,P<0.001)and birth weight below 1100 g(OR=5.7,95%CI:1.7-19.4,P<0.01).Conclusions:In patients with NEC,the presence of PDA is associated with an increased risk of ***,when important differences between the two study groups are controlled,only birth weight and disease severity may independently predict mortality.

关键词： congenital heart disease necrotizing enterocolitis neonatal mortality patent ductus arteriosus

Keynote Speech 1: Mobile image browsing

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Keynote Speech 1: Mobile image browsing

Nigeria’s ‘Great Leap’ Past South Africa

2011 2nd Asia-Pacific Conference on Wearable Computing Systems

作者： Gerald schaefer Department of Computer Science Loughborough University

Image collections, both private and commercial, are ever growing meaning visual information is becoming more and more important. Moreover, the classical paradigm of how pictures are typically taken has changed completely, first with the spread of digital cameras and, more recently, with mobile devices equipped with integrated cameras. Clearly, these image repositories neeed to be managed, and tools for effectively and efficiently searching image databases are highly sought after. In my talk, I will present the idea of image database visualisation and image browsing as an intuitive and useful approach for accessing large image collections. After introducing the basic concepts, and some of our earlier（desktop-based） image browsing systems, I will then focus on our latest work in this area which is the development of effective image browsing applications for mobile devices such as mobile phones and tablets.

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ChinAfrica 2014年第6期6卷 34-35页

作者： Simon schaefer Hannah Edinger

IN a long overdue exercise, the National Bureau of Statistics of Nigeria recalculated the country＇s GDE dethroning South Africa as Africa＇s largest economy earlier this year. While the rebasing of economic output is a standard procedure usually done quite regularly by countries, Nigeria has not recalculated its GDP in more than 20 years. With a population of at least three times the size of the incumbent number one economy in Africa Nigeria＇s claim of the economic pole position in Africa did not come as a surprise. Its rise to the top was inevitable and arguably the only surprise may have been that it took the West African giant of 170 million people so long to do so.

关键词： Great Leap Nigeria’s Past South Africa