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Geochemical study of submicron particulate matter(PM1)in a metropolitan area

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Geoscience Frontiers 2022年第1期13卷 417-429页

作者： Ismael L.Schneider Elba C.Teixeira Guilherme L.dotto Diana Pinto Cheng-Xue Yang Luis F.O.Silva Postgraduate Program in Remote Sensing and Meteorology Universidade Federal do Rio Grande do SulAv.Bento Gonçalves9500 Porto AlegreRSBrazil Department of Civil and Environmental Universidad de la CostaCUCCalle 58#55-66BarranquillaAtlanticoColombia Research Department Fundação Estadual de Proteção Ambiental Henrique Luís RoesslerAv.Borges de Medeiros261Porto AlegreRSBrazil Chemical Engineering Department Federal University of Santa Maria97105-900 Santa MariaBrazil School of Earth Sciences and Resources China University of Geosciences BeijingBeijing 100083PR China Departamento de Ingeniería Civil y Arquitectura Universidad de LimaAvenida Javier Prado Este 4600–Santiago de Surco 1503Perú

Air pollution has become a major problem in urban areas due to increasing industrialization and *** this study ambient concentrations of PM1 and metal concentrations as well as source contributions were identified and quantified by using Positive Matrix Factorization(PMF)in receptor modeling in the Metropolitan Area of Porto Alegre,*** PM1 samples were collected on PTFE filters from December 2012 to December 2014 in two sampling *** ion and trace element concentrations were *** average concentrations were 12.8 and 15.2μg/m^(3) for Canoas and Sapucaia do Sul sites,*** ion contributions of PM1 were secondary pollutants such as sulfate and *** elements,especially Cu,Pb,Zn,Cd,and Ni also made important contributions which are directly associated with anthropogenic *** results show significantly higher levels in winter than in *** of the PM1 and the analyzed PM species and elements originated from anthropogenic sources,especially road traffic,combustion processes and industrial activities,which are grouped in 7 major contributing sources.A back-trajectory analysis showed that the long-range transport of pollutants was not relevant in relation to the contribution to PM1 and metal *** work highlights the importance of urban planning to reduce human health exposure to traffic and industrial emissions,combined with awareness-raising actions for citizens concerning the impact of indoor sources.

关键词： PM1 Trace elements Source apportionment PMF Back trajectory

Affinity Solvents for Intensified Organics Extraction: Development Challenges and Prospects

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Tsinghua Science and Technology 2006年第2期11卷 171-180页

作者： andré B. de Haan University of Twente Enschede The Netherlands

In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of classical solvents towards the desired solutes is usually insufficient, enforcing the need for complex and thus expensive separation schemes. Significant simplification and cost-reduction can be achieved when affinity solvents would be available that are able to recognize the solutes of interest by their molecular structure. The main development challenges to establish such affinity solvents are： Selection and incorporation of molecular recognition and complexation capabilities; Evaluation of extraction capabilities; Efficient re- covery and recycling of the affinity solvents; Implementation in industrial extraction equipment. This paper presents how these development challenges are addressed at the University of Twente, going all the way from affinity solvent design and synthesis, via high throughput screening and characterization up to pilot plant evaluation. Essential in the successful development of affinity solvents are structural cooperations with molecular chemists and custom synthesis companies for their design and synthesis. The various aspects are illustrated by several examples where newly developed environmentally benign affinity solvents appeared able to create major breakthroughs. The applications addressed involve oxygenates, sugars, and pharmaceutical ingredients, such as optical isomers and biomolecules.

关键词： affinity solvent organics extraction molecular recognition complexation reaction

Biliary stone causing afferent loop syndrome and pancreatitis

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World Journal of Gastroenterology 2006年第38期12卷 6229-6231页

作者： andré Roncon Dias Roberto Iglesias Lopes Department of General Surgery Hospital das Clínicas Faculdade de Medicina da Universidade de So Paulo So Paulo Brazil

We report the case of an 84-year-old female who had a partial gastrectomy with Billroth-Ⅱ anastomosis 24 years ago for a benign peptic ulcer who now presented an acute pancreatitis secondary to an afferent loop syndrome. The syndrome was caused by a gallstone that migrated through a cholecystoenteric fistula. This is the first description in the literature of a biliary stone causing afferent loop syndrome.

关键词： Afferent loop syndrome Biliary stone Acute pancreatitis Gallstone ileus

Aristotle＇s Immovable Movers： A Sketch

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Frontiers of Philosophy in China 2015年第2期10卷 273-286页

作者： andré Laks Department of Philosophy Panamerican University Col. Insurgentes Mixcoac CP03920 México D.F.

In keeping with a view that is explicitly formulated by Aristotle in his Motion of Animals, general kinetic principles must be specified according to the different types of movable entities existing in the universe. At issue, essentially, are the motions of the stars and the motions of animals. Whereas the cosmological immovable mover is the object of two complementary analyses （in Bk. Ⅷ of Physics and in Chs. 6 and 7 of Bk. Ⅻ of Metaphysics）, information on the immovability of the first mover responsible for animal motion is to be found in the psychological and psycho-physiological treatises （On the Soul, in Bk. Ⅰ, Chs. 3 and 4, and in Bk. Ⅲ, Ch. 10 and in Ch. 6 of the Motion of Animals）. But it is also found in Ch. 7, Bk. Ⅻ of the Metaphysics, in the very context of the argument concerning the absolutely first immovable mover of the world. This suggests that the two types of motion, that of the stars and that of animals, however distinct the arguments about them are, rest on a single scheme, and maybe even on a common principle. This is liable to surprise us, as much as stars and animals appear to us to belong to heterogeneous orders of reality. But the situation is different for Aristotle, who, as attentive as he is to differences, tends nonetheless to conceive the stars as living things of a particular kind. This fact is the source of a series of difficulties that Aristotle generously left for his many commentators to solve. Aim of this text, which was initially directed to a larger audience, is to set some of these complex issues in both simple and up to date terms.

关键词： Aristotle immovable movers final cause efficient cause soul animal motion

CRISPR/Cas9: Development and Application in Rice Breeding

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Rice science 2019年第5期26卷 265-281页

作者： Fernando Matías ROMERO andrés GATICA-ARIAS Laboratory of Plant Biotechnology School of Biology/Research Center in Cellular and Molecular Biology University of Costa Rica

Rice(Oryza sativa L.)is an important staple food crop worldwide due to its adaptability to different environmental *** of its great economic and social importance,there is a constant requirement for new varieties with improved agronomic characteristics,such as tolerance to different biotic(such as bacterium,fungus,insect and virus)and abiotic stresses(such as salinity,drought and temperature),higher yield and better organoleptic and nutritional *** the new genome editing technologies,the clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas)(CRISPR/Cas)system allows precise and specific edition in a targeted genome *** is one of the most frequently used techniques for the study of the function of new genes and for the development of mutant lines with enhanced tolerance to biotic and abiotic stresses,herbicide resistance or improved *** wide varieties of applications for this technology include simple non-homologous end joining,homologous recombination,gene replacement,and base *** this review,we analyzed how some of these applications have been used in rice cultivars to obtain rice varieties better adapted to current environmental conditions and market requirements.

关键词： rice CRISPR Cas genome editing biotic stress abiotic stress yield off-target mutation

Penalty Algorithms in Hilbert Spaces

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Acta Mathematica Sinica,English Series 2007年第2期23卷 229-236页

作者： Jean Pierre DUSSAULT Hai SHEN andré BandrAUK Département d'Informatique Faculté des Sciences.Université de Sherbrooke Viador inc Laboratoire de Chimie Théorique Faculté des Sciences Université de Sherbrooke

We analyze the classical penalty algorithm for nonlinear programming in Hilbert spaces and obtain global convergence results, as well as asymptotic superlinear convergence order. These convergence results generalize similar results obtained for finite-dimensional problems. Moreover, the nature of the algorithms allows us to solve the unconstrained subproblems in finite-dimensional spaces.

关键词： penalty methods infinite dimensional optimization

Human condition monitoring in hazardous locations using pervasive RFID sensor tags and energy-efficient wireless networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第9期13卷 674-688页

作者： Javier G.ESCRIBANO andrés GARCIA Autolog Group Industrial Engineering SchoolUniversity of Castilla-La ManchaAvda.Camilo José Cela s/n13071 Ciudad RealSpain

Tracking persons in dangerous situations as well as monitoring their physical condition, is often crucial for their safety. The systems commonly used for this purpose do not include individual monitoring or are too expensive and intrusive to be deployed in common situations. In this project, a mobile system based on energy-efficient wireless sensor networks (WSNs) and active radio frequency identification (RFID) has been developed to achieve ubiquitous positioning and monitoring of people in hazardous situations. The system designed can identify each individual, locate him/her, send data regarding their physical situation, and ascertain whether they are located in a confined space. A new algorithm called time division double beacon scheduling (TDDBS) has been implemented to increase operation time and data transmission rate of the nodes in the system. The results show that the use of this system allows us to find the location and state of a person, as well as to provide an analysis of the potential risks at each moment, in real time and in an energy-efficient way. In an emergency, the system also allows for quicker intervention, as it not only provides the location and causes of the event, but also informs about the physical condition of the individual at that moment.

关键词： Active RFID Wireless sensor networks (WSNs) ZigBee Human monitoring Time division double beacon sched-uling (TDDBS)

Vegetation recovery after fire in mountain grasslands of Argentina

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Journal of Mountain Science 2020年第2期17卷 373-383页

作者： Alejandro LOYDI Flavia AFUNK andrés GARCíA Renewable Natural Resources Center of the Semi-Arid Zone(CERZOS)–CONICET-UNS Bahia BiancaArgentina Department of Biology Biochemistry and PharmacySouth National UniversityBahfa BiancaArgentina Argentine Institute of Oceanography(IADO) CONICET-UNSBahia BlancaArgentina

Fire is a natural disturbance occurring every few years in many grasslands ecosystems. However, since European colonization, fire has been highly reduced or even suppressed in Argentinean grasslands, fostering ignitable material accumulation. This has led to occasional catastrophic controldemanding fire events, extended for larger areas. The aims of this work are to study vegetation recovery and change after a non-natural fire event in mountain grasslands. The study area is located in the Ventania mountain system, mid-eastern Argentina. We studied vegetation recovery after fire(January 2014) in two different communities: grass-steppes(grasslands) and shrub-steppes(open low shrublands). We measured vegetation cover, species richness and bare ground percentage in burned and unburned areas 1, 4, 8, 11 and 23 months after fire. Vegetation surveys were also performed at the end of the growing season(December) 11 and 23 months after fire. Data were analyzed using regression analysis, ANOVA and multivariate analysis(NMS, PERMANOVA). Both communities increased their vegetation cover at the same rate, without differences between burned and unburned areas after two years. Species richness was higher in shrublands and their recovery was alsofaster than in grasslands. Considering functional composition, besides transient changes during the first year after fire, there were no differences in abundance of different functional vegetation groups two years after fire. At the same time, shrublands showed no differences in species composition, while grasslands had a different species composition in burned and unburned plots. Also, burned grassland showed a higher species richness than unburned grassland. Data shown mountain vegetation in Pampas grassland is adapted to fire, recovering cover and richness rapidly after fire and thus reducing soil erosion risks. Vegetation in mountain Pampas seems to be well adapted to fire, but in grasslands species composition has changed due to fire.

关键词： Amelichloa caudata Forbs Grass Natural grassland Nassella trichotoma Piedmont valleys Shrubs Sierra de la Ventana Vegetation functional groups

Stellar structure model in hydrostatic equilibrium in the context of f(R)-gravity

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Research in Astronomy and Astrophysics 2017年第12期17卷 31-40页

作者： Raíla andr Gilberto M.Kremer Departamento de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil Manipal Centre for Natural Sciences Manipal UniversityManipal 576104India

In this work we present a stellar structure model from the f（R）-gravity point of view capable of describing some classes of stars（white dwarfs, brown dwarfs, neutron stars, red giants and the Sun）. This model is based on f（R）-gravity field equations for f（R） = R ＋ f2R2, hydrostatic equilibrium equation and a polytropic equation of state. We compare the results obtained with those found by Newtonian theory. It has been observed that in these systems, where high curvature regimes emerge,stellar structure equations undergo modifications. Despite the simplicity of this model, the results are satisfactory. The estimated values of pressure, density and temperature of the stars are within those determined by observations. This f（R）-gravity model has proved to be necessary to describe stars with strong fields such as white dwarfs, neutron stars and brown dwarfs, while stars with weaker fields, such as red giants and the Sun, are best described by Newtonian theory.

关键词： cosmology:theory stars:general massive brown dwarfs white dwarfs neutron