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Journal of Magnesium and Alloys 2022年第9期10卷 2574-2587页

作者： Maryam Rahmati Keyvan Raeissi Mohammad Reza Toroghinejad Amin Hakimizad monica Santamaria Department of Materials Engineering Isfahan University of TechnologyIsfahan 84156-83111Iran Yekta Mobaddel Pars Co. Science and Technology CampusYazd UniversityYazd 89158-18411Iran Dipartimento di Ingegneria Università di PalermoViale Delle ScienzeEd.690128PalermoItaly

In this research,plasma electrolytic oxidation coatings were prepared on AZ31 Mg alloy in a silicate-based solution containing K_(2)TiF_(6) using bipolar and soft sparking waveforms with 10,20,and 30%cathodic duty *** coatings displayed a net-like surface morphology consisted of irregular micro-pores,micro-cracks,fused oxide particles,and a sintered *** to the incorporation of TiO_(2) colloidal particles and the cathodic pulse repair effect,most of the micro-pores were ***-term corrosion performance of the coatings was investigated using electrochemical impedance spectroscopy during immersion in 3.5 wt.%NaCl solution up to 14 *** coating grown by the soft sparking waveform with a 20%cathodic duty cycle having the lowest porosity(6.2%)and a sharp layer concentrated in F element at the substrate/coating interface shows the highest corrosion *** friction coefficient of this coating has remained stable during the sliding even under 5 N normal load,showing relatively higher wear resistance than other *** coating produced using the equivalent unipolar waveform,as the reference specimen,showed the highest friction coefficient and the lowest wear resistance despite its highest micro-hardness.

关键词： Plasma electrolytic oxidation Pulsed waveforms AZ31 Mg alloy Dipotassium titanium hexafluoride Corrosion resistance Wear resistance

SYNTHESIS AND PROPERTIES OF HOMOPOLYMER AND COPOLYMERS OBTAINED FROM 1-OCTADECENE WITH ZIRCONOCENE CATALYSTS

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Chinese Journal of Polymer Science 2000年第3期18卷 249-254页

作者： Raul Quijada Juan L.Guevara Rene rojas Franco M.Rabagliati Departamento de Ingenieria Quimica Facultad de Ciencias Fisicasy MatematicasUniversidad de ChileCasilla 2777SantiagoChile Departamento Ciencias Quimicas Facultad Quimicay BiologiaUniversidad de Santiago de ChileCasilla 40SantiagoChile

Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be *** metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-Me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization *** show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest *** lower temperatures(≤30℃)thedifferences are *** the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-Me_(2)Si(Ind)_(2)ZrCl_(2)were *** results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NMR analysis shows that thecomposition of the copolymerization products depends on the catalytic *** obtained with rac-Me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer *** analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization *** homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-Me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not *** type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower *** measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关键词： Homopolymerization Copolymerization Metallocene Catalytic activity Poly-l-octadecene

Assessment of the potential responses of ecosystem services to anthropogenic threats in the Eten wetland,Peru

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Ecosystem Health and Sustainability 2021年第1期7卷 215-231页

作者： Tania V.rojas Karin Bartl Jorge D.Abad Department of Engineering Pontificia Universidad Católica Del PerúLimaPeruFormerlyUniversidad De Ingenieria Y Tecnologia-UTECLimaPeru Department of Education Research&DevelopmentRed YakuLimaPeru Peruvian Life Cycle Assessment and Industrial Ecology Network-PELCAN Department of EngineeringPontificia Universidad Católica Del PerúLimaPeru

Introduction:Coastal wetlands are currently threatened by human drivers,such as agriculture,infrastructure development,and urban *** on these ecosystems disturb their morphology and biogeochemical cycles,resulting in the degradation of ecosystem ***,little has been done to understand the wetland response to identify proper conservation *** the Peruvian coast,wetlands present a diversity of landscapes that face similar threats and pressures;however,the ecosystem response in each one may be ***:This study aims to assess the environmental impacts on ecosystem services based on the understanding of geomorphic features and the status of the Eten coastal wetland(Peru).Methods:The methodology combines the application of open-source GIS tools and the collection of field data to characterize the geomorphic settings and to analyze the changes in environmental ***,the main threats and pressures on the Eten wetland are defined and related to impacts on ecosystem services using a cause-effect ***:Overall,the results indicated that the river plays a vital role in defining the wetland landscape and *** biological diversity of aquatic habitats is disturbed by hydraulic structures and agricultural *** land use affects supporting and regulation services,such as water regulation.

关键词： Ecosystem services wetland functions human-environment interactions Eten wetland coastal management

Influence of local and landscape environmental factors on alpha and beta diversity of macroinvertebrates in Andean rivers

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Journal of Mountain Science 2023年第9期20卷 2487-2501页

作者： DIAZ-rojas Camila A PEDROZA-RAMOS Adriana X BARRERA-HERRERA July A ROA-FUENTES Camilo A Ecology Unit in Aquatic Systems Research Group Pedagogical and Technological University of ColombiaUPTCAvenida Central del Norte 39-115TunjaBoyacáColombia

Research on macroinvertebrate community structure in Andean rivers has been oriented towards describing patterns of alpha and gamma diversity by taking into account environmental predictors at local spatial scales(e.g.,micro-and mesohabitats).However,the patterns of beta diversity and the importance of landscape-scale variables have been evaluated to a lesser *** objective of this study was to describe the patterns of alpha and beta diversity of benthic macroinvertebrates in the Andean rivers of the Orinoco basin and their relationship with local and landscape environmental variation.A stratified random sampling of macroinvertebrates was carried out at 40 sites(comprising an altitudinal range of between 500 and 2900 m.a.s.l.),local and landscape variables were *** results showed that the variation of alpha diversity was influenced by local and landscape variables,which are directly and indirectly related to the contribution of sediments,substrate composition and flow velocity,providing a heterogeneity of *** beta diversity was explained by the combined effect of local and landscape *** the beta diversity phenomena,turnover was predominant while nestedness presented a minor contribution and both were explained in greater proportion by local descriptors and some landscape variables,specifically those of a geomorphological *** results concur with the view of an environmental and spatial hierarchy within the river habitat and highlight the influence of multiple scales on macroinvertebrate *** above suggests that both local and landscape scales must necessarily be considered for environmental management and the conservation of Andean lotic ecosystems.

关键词： Andean lotic systems Andean agroecosystems Instream habitat Landcover Turnover Nestedness

Abdominal compartment syndrome among surgical patients

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World Journal of Gastrointestinal Surgery 2021年第4期13卷 330-339页

作者： monica Leon Luis Chavez Salim Surani Department of Medicine Centro Medico ABCCiudad de Mexico 01120Mexico Department of Medicine University of TexasEl PasoTX 79905United States Department of Medicine Texas A&M UniversityCorpus ChristiTX 78405United States

Abdominal compartment syndrome(ACS)develops when organ failure arises secondary to an increase in intraabdominal *** abdominal pressure is determined by multiple factors such as blood pressure,abdominal compliance,and other factors that exert a constant pressure within the abdominal *** conditions in the critically ill may increase abdominal pressure compromising organ perfusion that may lead to renal and respiratory *** surgical and trauma patients,aggressive fluid resuscitation is the most commonly reported risk factor to develop *** conditions that have also been identified as risk factors are ascites,hemoperitoneum,bowel distention,and large *** patients with abdominal trauma possess a higher risk of developing intra-abdominal hypertension(IAH).Certain surgical interventions are reported to have a higher risk to develop IAH such as damage control surgery,abdominal aortic aneurysm repair,and liver transplantation among *** monitoring of organ function and intra-abdominal pressure(IAP)allows clinicians to diagnose ACS rapidly and intervene with target-specific management to reduce *** decompression followed by temporary abdominal closure should be considered in all patients with signs of organ *** is still a great need for more studies to determine the adequate timing for interventions to improve patient outcomes.

关键词： Intra-abdominal hypertension Abdominal compartment syndrome Intraabdominal pressure Open abdomen treatment Multiple organ failure Surgical decompression

Lane Detection by Smartphones-Based on Non-Camera Sensors

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Lane Detection by Smartphones-Based on Non-Camera Sensors

作者： Alejandro Mu(?)oz rojas（阿来）北京邮电大学

学位级别：硕士

Smart-Lane探测器是一种用来区分汽车的车道位置中的主路和辅路的系统。它需要借助如智能驱动系统、无人驾驶汽车和许多其他应用程序系统服务来运行。这个研究致力于开发一个显示汽车行驶车道位置的应用程序,便于司机知晓汽车是在主路... 详细信息

Smart-Lane探测器是一种用来区分汽车的车道位置中的主路和辅路的系统。它需要借助如智能驱动系统、无人驾驶汽车和许多其他应用程序系统服务来运行。这个研究致力于开发一个显示汽车行驶车道位置的应用程序,便于司机知晓汽车是在主路或辅路上行驶。例如:如果司机想要退出主干道则需要改变到最右边车道,此时司机若位于正确的车道他就可以平稳和安全地驶入出口或辅道。本研究提供了检测车道的另一种方案。当车在主干道或辅路时,无需借助摄像头和额外的设备,只需要司机的电话就能定位车道。由于其他可替代的检测车道的方法需要质量高、校对精准的摄像机或特殊传感器,就算是一些预置的应用程序也只能兼容一些车型,所以这就是为什么要开发一个智能手机应用程序的原因。此项智能手机应用程序可以避免这些不便并且可以让司机有相同的或者更加舒适的体验,而只需要司机在其智能手机里安装智能车道探测程序。

关键词：驾驶辅助系统智能车道检测手机

Analytics of big geosocial media and crowdsourced data

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Big Earth Data 2021年第1期5卷 1-4页

作者： Songnian Li monica Wachowicz Hongchao Fan Ryerson University TorontoCanada University of New Brunswick FrederictonCanada Norwegian University of Science and Technology TrondheimNorway

Numerous crowdsourcing and social media platforms such as CrowdSpring,Idea Bounty,DesignCrowd,Facebook,Twitter,Flickr,Weibo,WeChat,and Instagram are creating and sharing vast amounts of user-generated content that can reveal timely and useful infor-mation for detecting traffic patterns,mitigating security risks and other types of time-critical events,discovering social structures characteristics,predicting human movement,***,also known as volunteered geographic information(VGI),has added a new dimension to traditional geospatial data acquisition by providing fine-grained proxy data for human activity research in urban studies(Chen et al.,2016;Niu&Silva,2020).However,analyzing big geosocial media and crowdsourced data brings significant methodological and theoretical challenges due to the uncertain user representability when referring to human behavior in general,the inherent noisy data that requires high-performance cost of preprocessing,and the heterogeneity in quality and quantity of *** particular,geosocial media data and their derived metrics can provide valuable insights and policy strategies,but they require a deep understanding of what the metrics actually measure(Zook,2017).All of these underpin complex assessments,not mention-ing the ethnic and privacy ***,new sets of methods and tools are required to analyze the big data from crowdsourcing and social media platforms.

关键词： source media covering

Wound dressing products:A translational investigation from the bench to the market

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Engineered Regeneration 2022年第2期3卷 182-200页

作者： Rossella Laurano monica Boffito Gianluca Ciardelli Valeria Chiono Politecnico di Torino Mechanical and Aerospace Engineering DepartmentCorso Duca degli Abruzzi 2410129 TorinoItaly Centro 3R Interuniversity Center for the Promotion of 3Rs Principles in Teaching and ResearchPisaItaly

Chronic skin wounds affect more than 40 million patients globally and represent a severe growing burden for the healthcare systems,with annual costs expected to exceed$15 billions by *** satisfy the huge demand for effective wound care products,different types of wound dressings have been introduced on the market dur-ing the last *** on“the moist wound healing theory”postulated by Prof Winter in 1962,bandages were initially designed to recreate the optimal wound environment to favor the healing ***,thanks to the advancements achieved in biomaterial design and processing,biotechnology,imaging and electronic fields,great effort has been devoted to the development of formulations able to actively participate to tissue ***,both the literature and the market report the design of medicated wound dressings,i.e.,wound care products releasing anti-microbial agents,anti-inflammatory drugs,or bioactive *** this scenario,this review aims at critically describing the currently available wound care products,highlighting their proved effec-tiveness in wound ***,an overview of the main strategies exploited to design personalized wound dressings has been ***,concerns on regulatory affairs and practical issues limiting the clinical translation of advanced research platforms have also been discussed.

关键词： Hard-to-close wounds Wound dressing effectiveness Medicated wound bandages Advanced wound care products Personalized medicine Regulatory affairs

Is obesity a disease?-the evolving concepts, cancer paradox and association with improved cancer immunotherapy efficacy

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Hepatobiliary Surgery and Nutrition 2020年第2期9卷 247-249页

作者： monica Cheng Richard B.Gunderman Department of Radiology and Imaging Sciences Indiana University School of MedicineIndianapolisIndianaUSA

Obesity represents a growing health problem in the United States and worldwide,with a prevalence that has doubled since 1980(1).In the United States,70%of adults and 37%of adolescents are overweight or *** chronic health implications of obesity make it a public health issue with significant economic *** promoting an altered whole-body physiology,obesity increases the risk for chronic diseases including diabetes,cardiovascular disease,and cancer(2).

关键词： obesity cancer cardiovascular

Delayed seed dispersal species and related traits in the desert of the United Arab Emirates

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Journal of Arid Land 2021年第9期13卷 962-976页

作者： Teresa NAVARRO Hatem A SHABANA Ali EL-KEBLAWY Noelia HIDALGO-triana Department of Botany and Plant Physiology Faculty of ScienceUniversity of MalagaMalaga 29080Spain Sharjah Seed Bank and Herbarium Sharjah Research AcademySharjah 60999United Arab Emirates Nature Conservation Sector Egyptian Environmental Affairs AgencyCairo 11728Egypt Department of Applied Biology Faculty of ScienceUniversity of SharjahSharjah 27272United Arab Emirates Department of Biology Faculty of ScienceAl-Arish University 45511Egypt

The ability of plants to safely retain seeds in the mother plant is an adaptive mechanism described in many desert ***,research about delayed seed dispersal species in the desert of the United Arab Emirates(UAE)is *** study aims to identify these delayed seed dispersal species and assess the relationships of the presence of delayed seed dispersal with plant growth form,habit,spatial dispersal,antitelechoric mechanism,and seed release *** relationships between the presence of delayed seed dispersal and the above studied traits were assessed by using the Pearson Chi-square test and Nonlinear Principal Components Analysis(NLPCA).Results showed that a total of 46 delayed seed dispersal species were recorded(15.0%of 307 studied species)and the highest incidence occurred in the Fabaceae family(17.4%).Delayed seed dispersal species were predominantly perennial plants(73.9%)with spatial restricted dispersal(67.4%),which released seed in the dry season(45.7%).The dominant groups of delayed seed dispersal species were persistent fruits species and synaptospermy(28.3%).All graminoids showed persistent lignified fruits,while prostrate annuals were basicarpic species with *** habitats had the highest number of delayed seed dispersal species(54.3%),whereas salt flats had the lowest(23.9%).In the desert of the UAE,delayed seed dispersal species spread seeds until the end of the dry and windy season,thus breaking seed dormancy at this time and ensuring seed germination in the next arrival of the rainy *** morphological and ecological adaptation of delayed dispersal species is essential to the survival and sustainable development of vegetation in desert environments.

关键词： Arabian desert delayed dispersal restricted dispersal persistent fruits seed release time myxospermy synaptospermy