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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

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

Endoscopic stenting for inoperable malignant biliary obstruction: A systematic review and meta-analysis

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World Journal of Gastroenterology 2015年第47期21卷 13374-13385页

作者： Leonardo Zorrón Pu Eduardo Guimaraes Hourneaux de moura Wanderley Marques Bernardo Felipe Iankelevich Baracat Ernesto Quaresma Mendonca andréKondo Gustavo Oliveira Luz Carlos Kiyoshi Furuya Júnior Everson Luiz de Almeida Artifon Gastrointestinal Endoscopy Division Department of GastroenterologyHospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo Guidelines Program Coordinator Brazilian Medical Association

AIM: To analyze through meta-analyses the benefits of two types of stents in the inoperable malignant biliary ***: A systematic review of randomized clinical trials(RCT) was conducted, with the last update on March 2015, using EMBASE, CINAHL(EBSCO), MEDLINE, LILACS/CENTRAL(BVS), SCOPUS, CAPES(Brazil), and gray literature. Information of the selected studies was extracted in sight of six outcomes: primarily regarding dysfunction, complication and reintervention rates; and secondarily costs, survival, and patency time. The data about characteristics of trial participants, inclusion and exclusion criteria and types of stents were also extracted. The bias was mainly assessed through the JADAD scale. This meta-analysis was registered in the PROSPERO database by the number CRD42014015078. The analysis of the absolute risk of the outcomes was performed using the software Rev Man, by computing risk differences(RD) of dichotomous variables and mean differences(MD) of continuous variables. Data on RD and MD for each primary outcome were calculated using the MantelHaenszel test and inconsistency was qualified and reported in χ2 and the Higgins method(I2). Sensitivity analysis was performed when heterogeneity was higher than 50%, a subsequent assay was done and other findings were compiled. Student's t-test was used for the comparison of weighted arithmetic means regarding secondary ***: Initial searching identified 3660 studies; 3539 were excluded through title, repetition, and/or abstract, while 121 studies were fully assessed and were excluded mainly because they did not compare self-expanding metal stents(SEMS) and plastic stents(PS), leading to thirteen RCT selected, with 13 articles and 1133 subjects meta-analyzed. The mean age was 69.5 years old, that were affected mostly by bile duct(proximal) and pancreatic tumors(distal). The preferred SEMS diameter used was the 10 mm(30 Fr) and the preferred PS diameter used was 10 Fr. In the metaanalysis

关键词： Biliary tract neoplasms Malignant biliaryobstruction Jaundice Palliative care Endoscopicretrograde cholangiopancreatography Stent Systematicreview Meta-analysis

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

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)

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

Effect of thermo-mechanical conditions during constrained friction processing on the particle refinement of AM50 Mg-alloy phases

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Journal of Magnesium and Alloys 2024年第6期12卷 2298-2311页

作者： Camila Caroline de Castro andréMartins Neves Benjamin Klusemann Helmholtz-Zentrum Hereon Institute of Material and Process DesignSolid-State Materials Processing21502 GeesthachtGermany Helmholtz-Zentrum Hereon Institute of Hydrogen TechnologySystem Design for Mobility21502 GeesthachtGermany Helmut Schmidt University/University of the German Federal Armed Forces Hamburg Department of Mechanical and Civil Engineering22043 HamburgGermany Leuphana University Lüneburg Institute for Production Technology and Systems21335 LüneburgGermany

Constrained Friction Processing(CFP)is a novel solid-state processing technique suitable for lightweight materials,such Mg-and *** technique enables grain size refinement to fine or even ultrafine *** this study,the effect of CFP on the microstructural refinement of AM50 rods is investigated in terms of particle size and morphology of the eutectic and secondary phases originally present in the base material,in particular the eutecticβ-Mg_(17)Al_(12)and Al-Mn *** that purpose,as-cast and solution heat-treated base material and processed samples were *** Al_(8)Mn_(5) intermetallic phase was identified as the main secondary phase present in all samples before and after the processing.A notorious refinement of these particles was observed,starting from particles with an average equivalent length of a few micrometers to around 560 nm after the *** refinement of the secondary phase refinement is attributed to a mechanism analogous to the attrition comminution,where the combination of temperature increase and shearing of the material enables the continuous breaking of the brittle intermetallic particles into smaller *** for the eutectic phase,the results indicate the presence of the partially divorcedβ-Mg_(17)Al_(12)particles exclusively in the as-cast base material,indicating that no further phase transformations regarding the eutectic phase,such as dynamic precipitation,occurred after the *** the case of the processed as-cast material analyzed after the CFP,the thermal energy generated during the processing led to temperature values above the solvus limit of the eutectic phase,which associated with the mechanical breakage of the particles,enabled the complete dissolution of this ***,CFP was successfully demonstrated to promote an extensive microstructure refinement in multiple aspects,in terms of grain sizes of theα-Mg phase and presence and morphology of the Al-Mn and eutecticβ-Mg_(17)Al_(12).

关键词： Constrained friction processing AM50 Refill friction stir spot welding Extrusion β-Mg_(17)Al_(12) Al-Mn phases