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Distribution,Properties,Land Use and Management of Mollisols in South America

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Chinese Geographical Science 2011年第5期21卷 511-530页

作者： Artigas Duran hector Morris Guillermo Studdert LIU Xiaobing Key Laboratory of Mollisols Agroecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China Faculty of Agronomy Garzon 780 12900 Montevideo Uruguay Institute of Soils INTA-CIRN CC 25 (1712) Castelar Buenos Aires Argentina Faculty of Agricultural Sciences National University of Mar Del Plata CC 276 (B7620WAP) Balcarce Buenos Aires Argentina

Mollisols are common in South America. They cover about 8.87 × 107ha, 1.3 × 107ha and 4.3 × 106ha in Argentina, Uruguay and Southern Brazil respectively, which is 11.5% of the world total. Most of South American Mollisols were developed on Pleistocene and Holocene sediments and lie within the limits of the temperate zone, though the extreme north is bordering subtropical and the extreme south is within a cold-temperate zone. All suborders of Mollisols occur in Argentina, the most extensive being Udolls followed by Ustolls, whereas only Udolls, Aquolls and Albolls occur in Uruguay. Vertisols in Uruguay have many properties similar to Mollisols, and the occurrence of Vertisols is strongly associated with Mollisols. The Pampean Mollisols are a significant component of the global breadbasket of modem times. The main Argentine crops are wheat, corn, sorghum, barmy, soybeans and sunflower, while Mollisols in Uruguay remain mostly dedicated to cattle and sheep grazing though crop production has been increasing very rapidly in the last decade. Throughout South America, research has shown that Mollisols are experiencing losses of soil organic matter and nutrients, and degradation of physical properties after long cropping periods, resulting in soil scientists calling for increased conservation practices to reduce future losses and a deterioration of soil quality, and thus a more sustainable agriculture in the region.

关键词： Mollisols classification sustainability soil fertility no tillage South America

Maneuvering Angle Rigid Formations With Global Convergence Guarantees

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IEEE/CAA Journal of Automatica Sinica 2022年第8期9卷 1464-1475页

作者： Liangming Chen Zhiyun Lin hector Garcia de Marina Zhiyong Sun Mir Feroskhan School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Department of Computer Architecture and Technology and also with CITICUniversity of Granada18014 GranadaSpain Department of Electrical Engineering Eindhoven University of Technology5600 MB Eindhoventhe Netherlands

Angle rigid multi-agent formations can simultaneously undergo translational,rotational,and scaling maneuvering,therefore combining the maneuvering capabilities of both distance and bearing rigid ***,maneuvering angle rigid formations in 2D or 3D with global convergence guarantees is shown to be a challenging problem in the existing literature even when relative position measurements are *** by angle-induced linear equations in 2D triangles and 3D tetrahedra,this paper aims to solve this challenging problem in both 2D and3D under a leader-follower *** the 2D case where the leaders have constant velocities,by using local relative position and velocity measurements,a formation maneuvering law is designed for the followers governed by double-integrator *** the leaders have time-varying velocities,a sliding mode formation maneuvering law is proposed by using the same *** the 3D case,to establish an angle-induced linear equation for each tetrahedron,we assume that all the followers'coordinate frames share a common Z ***,a formation maneuvering law is proposed for the followers to globally maneuver Z-weakly angle rigid formations in *** extension to Lagrangian agent dynamics and the construction of the desired rigid formations by using the minimum number of angle constraints are also *** examples are provided to validate the effectiveness of the proposed algorithms.

关键词： Index Terms—Angle rigid formations formation control formation maneuvering global convergence multi-agent systems

Current protective strategies in liver surgery

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World Journal of Gastroenterology 2010年第48期16卷 6098-6103页

作者： Kurinchi S Gurusamy hector D Gonzalez Brian R Davidson HPB and Liver Transplantation Royal Free CampusUniversity College London Medical SchoolRoyal Free Hospital

During liver resection surgery for cancer or liver transplantation,the liver is subject to ischaemia (reduction in blood flow) followed by reperfusion (restoration of blood flow),which results in liver injury [ischemiareperfusion (IR) or IR injury]. Modulation of IR injury can be achieved in various ways. These include hypothermia,ischaemic preconditioning (IPC) (brief cycles of ischaemia followed by reperfusion of the organ before the prolonged period of ischaemia i.e. a conditioning response),ischaemic postconditioning (conditioning after the prolonged period of ischaemia but before the reperfusion),pharmacological agents to decrease IR injury,genetic modulation of IR injury,and machine perfusion (pulsatile perfusion). Hypothermia decreases the metabolic functions and the oxygen consumption of organs. Static cold storage in University of Wisconsin solution reduces IR injury and has prolonged organ storage and improved the function of transplanted grafts. There is currently no evidence for any clinical advantage in the use of alternate solutions for static cold storage. Although experimental data from animal models suggest that IPC,ischaemic postconditioning,various pharma-cological agents,gene therapy,and machine perfusion decrease IR injury,none of these interventions can be recommended in clinical practice. This is because of the lack of randomized controlled trials assessing the safety and efficacy of ischaemic postconditioning,gene therapy,and machine perfusion. Randomized controlled trials and systematic reviews of randomized controlled trials assessing the safety and efficacy of IPC and various pharmacological agents have demonstrated biochemical or histological improvements but this has not translated to clinical benefit. Further well designed randomized controlled trials are necessary to assess the various new protective strategies in liver resection.

关键词： Liver Hepatectomy Liver transplantation Ischemia-reperfusion injury Hypothermia Ischaemic preconditioning

Experiential Learning in a Canadian Physical Education Class:A Comparative Perspective from Pre-service PE Teachers in Canada and China

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ECNU Review of Education 2022年第3期5卷 509-519页

作者： Sydney hector Geri Salinitri Faculty of Education University of WindsorWindsorOntarioCanada N9B3P4

This article focuses on a comparative analysis of traditional Physical Education games and experiential learning on the part of teacher candidates enrolled in an Ontario Faculty of Education and onein Southwest China.

关键词： Canadian Chinese daily physical activity games comparison pedagogy physical education

The transcription factor ZEB1 promotes an aggressive phenotype in prostate cancer cell lines

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Asian Journal of Andrology 2018年第3期20卷 294-299页

作者： Octavio Orellana-Serradell Daniela Herrera Enrique A Castellon hector R Contreras Department of Basic and Clinical Oncology Faculty of Medicine University of Chile Independencia Santiago 8380453 Chile.

It has been reported that one of the factors that promotes tumoral progression is the abnormal activation of the epithelial-mesenchymal transition program. This process is associated with tumoral cells acquiring invasive and malignant properties and has the transcription factor zinc finger E-box-binding homeobox 1 （ZEB1） as one of its main activators. However, the role of ZEB1 in promoting malignancy in prostate cancer （PC, a） is still unclear. Here, we report that ZEB1 expression correlates with Gleason score in PCa samples and that expression of ZEB1 regulates epithelial-mesenchymal transition and malignant characteristics in PCa cell lines. The results showed that ZEB1 expression is higher in samples of higher malignancy and that overexpression of ZEB1 was able to induce epithelial-mesenchymal transition by upregulating the mesenchymal marker Vimentin and downregulating the epithelial marker E-Cadherin. On the contrary, ZEB 1 silencing repressed Vimentin expression and upregulated E-Cadherin. ZEB1 expression conferred enhanced motility and invasiveness and a higher colony formation capacity to 22Rvl cells whereas DU145 cells with ZEB1 silencing showed a decrease in those same properties. The results showed that ZEB1 could be a key promoter of tumoral progression toward advanced stages of PC, a.

关键词： epithelial-mesenchymal transition prostate cancer transcriptional repression ZEB1

The transcription factor ZEB1 promotes chemoresistance in prostate cancer cell lines

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Asian Journal of Andrology 2019年第5期21卷 460-467页

作者： Octavio Orellana-Serradell Daniela Herrera Enrique A Castellon hector R Contreras Department of Basic and Clinical Oncology Faculty of MedicineUniversity of ChileIndependenciaSantiago 8380453Chile

One of the factors promoting tumoral progress is the abnormal activation of the epithelial-mesenchymal transition(EMT)program which has been associated with chemoresistance in tumoral *** transcription factor zinc finger E-box-binding homeobox 1(ZEB1),a key EMT activator,has recently been related to docetaxel resistance,the main chemotherapeutic used in advanced prostate cancer *** mechanisms involved in this protective effect are still *** a previous work,we demonstrated that ZEB1 expression induced an EMT-like phenotype in prostate cancer cell *** this work,we used prostate cancer cell lines 22Rvl and DU145 to study the effect of ZEB1 modulation on docetaxel resistance and its possible *** results showed that ZEB1 overexpression conferred to 22Rvl cell resistance to docetaxel while its silencing made DU145 cells more sensitive to *** of resistance markers showed no presenee of ATP-binding cassette subfamily B member 1(MDR1)and no changes in breast cancer resistance protein(BCRP)or ATP-binding cassette subfamily C member 10(MRP7).However,a correlation between ZEB1,multidrug resistance-associated protein 1(MRP1),and ATP-binding cassette subfamily C member 4(MRP4)expression was ***4 inhibition,using MK571,resensitized cells with ZEB1 overexpression to docetaxel *** addition,modulation of ZEB1 and subsequent change in MRP4 expression correlated with a lower apoptotic response to docetaxel,characterized by lower B-cell lymphoma 2(Bcl2),high BCL2-associated X protein(Bax),and high active caspase 3 *** response to docetaxel in our model seems to be mediated mainly by activation of the apoptotic death *** results showed that modulation of MRP4 could be a mediator of ZEBl-related resistance to docetaxel in prostate cancer,making it a possible marker for chemotherapy response in patients who do not express MDR1.

关键词： chemoresistance prostate cancer ZEB1

Performance assessment of borehole arrangements for the design of rectangular shallow foundation systems

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第12期15卷 3291-3304页

作者： Marcin Chwała Danko J.Jerez hector A.Jensen Michael Beer Wrocław University of Science and Technology Poland Institute for Risk and Reliability Leibniz University HannoverGermany Departamento de Obras Civiles Universidad Técnica Federico Santa MaríaChile International Joint Research Center for Resilient Infrastructure&International Joint Research Center for Engineering Reliability and Stochastic Mechanics Tongji UniversityShanghai200092China Institute for Risk and Uncertainty and School of Engineering University of LiverpoolUnited Kingdom

This study proposes a framework to evaluate the performance of borehole arrangements for the design of rectangular shallow foundation systems under spatially variable soil conditions. Performance measures are introduced to quantify, for a fixed foundation layout and given soil sounding locations, the variability level of the foundation system bearing capacities in terms of their mean values and standard deviations. To estimate these measures, the recently proposed random failure mechanism method (RFMM) has been adopted and extended to consider any arrangement of rectangular foundations and boreholes. Hence, three-dimensional bearing capacity estimation under spatially variable soil can be efficiently performed. Several numerical examples are presented to illustrate the applicability of the proposed framework, including diverse foundation arrangements and different soil correlation structures. Overall, the proposed framework represents a potentially useful tool to support the design of geotechnical site investigation programs, especially in situations where very limited prior knowledge about the soil properties is available.

关键词： Foundations Geotechnical engineering Bearing capacity Optimal borehole placement Soil spatial variability

Tribological performance of iron- and nickel-base self-lubricating claddings containing metal sulfides at high temperature

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Friction 2022年第12期10卷 2069-2085页

作者： hector TORRES Tugce CAYKARA Jens HARDELL Janne NURMINEN Braham PRAKASH Manel RODRIGUEZ RIPOLL AC2T research GmbH Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria Department of Applied Physics and Mechanical Engineering LuleåUniversity of TechnologyLuleå97187Sweden Castolin Eutectic GmbH Gutenbergstraße 10Kriftel 65830Germany Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

Iron-based coatings with the incorporation of solid lubricants have been prepared by means of laser cladding,in an effort to control friction and decrease tool wear at high temperatures during metal forming *** choice of a Fe-based powder has been considered advantageous,as it can lead to decreased costs compared to nickel-based claddings previously studied by the authors,in addition to having a lower environmental *** particular,the incorporation of transition metal dichalcogenides such as MoS_(2) as precursors leads to the encapsulation of silver in Fe-based self-lubricating claddings,resulting in a uniform distribution of the soft metal across the thickness of the *** tribological evaluation of the claddings at high temperatures shows that the addition of lubricious compounds leads to lower friction at room temperature and significantly decreased wear up to 600℃ compared to the unmodified iron-based reference alloy,although higher than similar self-lubricating Ni-based *** order to cast light into these observed differences,the corresponding microstructures,phase composition,and self-lubricating mechanisms have been studied and compared for Fe-and Ni-based claddings having both of them the addition of silver and MoS_(2).The results suggest a key role of the formation of protective tribolayers on the counter body during high temperature sliding *** simulation of the phase evolution during solidification reveals that the formation of different chromium-and nickel-based metal sulfides in Fe-and Ni-claddings during laser cladding by the decomposition of MoS_(2) plays a key role in determining their tribological behaviour at high temperatures.

关键词： high temperature laser cladding self-lubrication metal forming chromium sulphide MoS_(2)

A Two-Player Coalition Cooperative Scheme for the Bodyguard Allocation Problem

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Journal of Computer Science & Technology 2018年第4期33卷 823-837页

作者： Jose Alberto Fernandez-Zepedu Daniel Brubeck-Salcedo Daniel Fajardo-Delgado hector Zatarain-Aceves Department of Computer Science Center for Scientific Research and Higher Education of Ensenada Ensenada BC 22860 Mexico Department of Systems and Computation Instituto Technol6gico de Ciudad Guzmdn Guzmdn JAL 49100 Mexico

We address the bodyguard allocation problem （BAP）, an optimization problem that illustrates the conflict of interest between two classes of processes with contradictory preferences within a distributed system. While a class of processes prefers to minimize its distance to a particular process called the root, the other class prefers to maximize it; at the same time, all the processes seek to build a communication spanning tree with the maximum social welfare. The two state-of-the-art algorithms for this problem always guarantee the generation of a spanning tree that satisfies a condition of Nash equilibrium in the system; however, such a tree does not necessarily produce the maximum social welfare. In this paper, we propose a two-player coalition cooperative scheme for BAP, which allows some processes to perturb or break a Nash equilibrium to find another one with a better social welfare. By using this cooperative scheme, we propose a new algorithm called FFC-BAPs for BAP. We present both theoretical and empirical analyses which show that this algorithm produces better quality approximate solutions than former algorithms for BAP.

关键词： bodyguard allocation problem coalitional game graph algorithm Nash equilibrium