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MODELING HEADCUT DEv.LOPMENT AND MIGRATION IN UPLAND CONCENTRATED FLOWS

International Journal of Sediment Research 2005年第4期20卷 281-294页

作者： Sean J. BENNETT carlos v. alonso Department of Geography University at Buffalo Buffalo NY 14261-0055 USA USDA-ARS National Sedimentation Laboratory P.O. Box 1157 Oxford MS 38655

On hillslopes and agricultural fields, discrete areas of intense, localized soil erosion commonly take place in the form of migrating headcuts. These erosional features significantly increase soil loss and landscape degradation, yet the unsteady, transient, and migratory habits of headcuts complicate their phenomenological and erosional characterization. Here a unique experimental facility was constructed to examine activ.ly migrating headcuts typical of upland concentrated flows. Essential components of the facility include a deep soil cav.ty with external drainage, rainfall simulator, capacity for ov.rland flow, and a v.deo recording technique for data collection. Results from these experiments show that: (1) after a short period of adjustment, headcut migration attained a steady-state condition, where the rate of migration, scour hole geometry, and sediment discharge remain constant with time; (2) boundary conditions of higher rates of ov.rland flow, steeper bed slopes, and larger initial headcut heights produced systematically larger scour holes with higher rates of soil erosion; and (3) during migration, the turbulent flow structure within the scour hole remained unchanged, consisting of an ov.rfall nappe at the brink transitioning into a reattached wall jet with two recirculation eddies within the plunge pool. The systematic behav.or of headcut dev.lopment and migration enabled the application of modified jet impingement theory to predict with good success the characteristics of the impinging jet, the depth of maximum scour, the rate of headcut migration, and the rate of sediment erosion. These laboratory data and the analytical formulation can be used in conjunction with soil erosion prediction technology to improv. the management of agricultural areas impacted by headcut dev.lopment and ephemeral gully erosion.

关键词： Soil erosion Headcuts Rills Gullies Jet impingement

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Freeze-thaw cycles and associated geomorphology in a post-glacial env.ronment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba v.lcano,Mexico

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Journal of Mountain Science 2024年第6期21卷 1954-1977页

作者： v.ctor SOTO carlos M.WELSH R. Kenji YOSHIKAWA Hugo DELGADO GRANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Env.ronmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Env.ronmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last Glacial Maximum,its icecap cov.red up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur abov. 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activ.ty decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes hav. resulted in significant alterations to the mountain slopes,which can hav. sev.re consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction Mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

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SEDIMENT TRANSPORT PROCESSES IN AGRICULTURAL WATERSHEDS

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International Journal of Sediment Research 2000年第2期 182-197页

作者： Roger A. Kuhnle Sean J. Bennett carlos v. alonso Ronald L. Bingner Eddy Langendoen(National Sedimentation Laboratory, U.S. Department of Agriculture, Agricultural Research Serv.ce, P.O. Box 1157,Oxford, Mississippi 38655, USA)

Determination of the total sediment load at selected points in agricultural Watersheds is important forev.ltating the status of a land area. Total sediment load date allows the identification of problem areaswhere the land surface is eroding at rates too high to allow sustainable agriculture and/or is producingsediment at rales such that aquatic organisms in nearby streams will be adv.rsely affected. Thedev.lopment of effectiv. sampling strategies and accurate computaional models requires accurateinformation on the processes by which sediment is transported. Researchers at the NationalSedimentation Laboratory are dev.loping and testing new methods to measure and predict sedimentbospoft. These new methods are prov.ding an improv.d understanding of the processes inv.lv.d insediment transport and are leading to important adv.ncements in the measurement and prediction ofsediment transport.

关键词： Total sediment load Sediment transport Sustainable agriculture Water quality Agricultural watershed

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Liquid crystal immunosensors for the selectiv. detection of Escherichia coli with a fast analysis tool

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Photonics Research 2024年第7期12卷 1564-1573页

作者： SANDRO C.OLIv.IRA MARIA S.SOARES BÁRBARA v.GONÇALv.S ANDREIA C.M.RODRIGUES AMADEU M.v.M.SOARES RITA G.SOBRAL NUNO F.SANTOS JAN NEDOMA PEDRO L.ALMEIDA carlos MARQUES CICECO-Av.iro Institute of Materials Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal i3N Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal Associate Laboratory i4HB-Institute for Health and Bioeconomy School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal CESAM-Centre for Env.ronmental and Marine Studies and Department of Biology University of Aveiro3810-193 AveiroPortugal Department of Telecommunications VSB-Technical University of OstravaOstrava 70800Czech Republic i3N-CENIMAT School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal UnIRE ISELPolytechnic Institute of Lisbon1549-020 LisbonPortugal Department of Physics VSB-Technical University of OstravaOstrava 70800Czech Republic

The consumption of contaminated food may cause serious illnesses,and traditional methods to detect Escherichia coli are still associated with long waiting times and high costs giv.n the necessity to transport samples to specialized *** is a need to dev.lop new technologies that allow cheap,fast,and direct monitoring at the site of ***,in this work,we dev.loped optical immunosensors for the selectiv. detection of ***,based on liquid crystal technology,whose molecules can align in different manners depending on the boundary conditions (such as substrates) as well as the env.ronment that they *** glass substrate was functionalized with *** antibody using cysteamine as an intermediate,and a v.rtical alignment was imposed on the liquid crystal molecules by using DMOAP during *** presence of bacteria disrupts the alignment of the liquid crystal molecules,changing the intensity of light emerging between cross polarizers,measured using a polarized optical microscope and a *** was possible to detect *** in suspensions in the concentration range from 2.8 cells/mL to 2.8×10^(9) cells∕*** was also ev.luated,and the sensors were used to analyze contaminated water samples.A prototype was dev.loped to allow faster,in-situ,and easier analysis av.iding bulky instruments.

关键词： crystal alignment analysis

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Determination of critical state line(CSL)for silty-sandy iron ore tailings subjected to low-high confining pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1684-1695页

作者： Nilo Cesar Consoli João v.tor de Azambuja Carv.lho Alexia Cindy Wagner Hugo carlos Scheuermann Filho Inácio Carv.lho Pedro Pazzoto Cacciari João Paulo de Sousa Silv. Civ.l Engineering Universidade Federal do Rio Grande do SulPorto AlegreRS90035-190Brazil Exploration and Mineral Projects-Mineral Dev.lopment Centre VALE S.A.Santa LuziaMG33040-900Brazil Department of Civ.l Geological and Mining EngineeringPolytechnique MontrealQuebecH3C 3A7Canada

The disposal of filtered tailings in high dry stacks can induce particle breakage,changing the material's behav.our during the structure's *** grading changes influence material properties at the critical state,and this is not mature for intermediate artificial soils(tailings)in a broad range of confining *** this paper,it aims to describe the behav.our of iron ore tailings in a spectrum of confining pressures broader than the reported in prev.ous studies.A series of consolidated drained(CD)triaxial tests was carried out with confining pressures ranging from 0.075 MPa to 120 *** results show that the amount of breakage plays an essential role in the response of iron ore *** existence of curv.d critical state line(CSL)in both specific v.lume(ν)-logarithm of mean effectiv. stress(p′)and dev.atoric stress(q)-mean effectiv. stress(p′)planes,and different responses in the dev.atoric stress-axial strain-v.lumetric strain curv.s were *** inv.rse S-shaped equation was proposed to represent the silty-sandy tailings'behav.our up to high pressures onν-lnp′*** proposed equation prov.des a basis for enhancing constitutiv. models and considers the ev.lution of the grading up to sev.re loading *** adjustment considered three regions with different responses associated with particle breakage at different pressure lev.ls.

关键词： Tailings Iron ore tailings dry stacking Silty-sandy material Critical state soil mechanics High confining pressures Particle breakage

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Mo_(2)P Monolayer as a Superior Electrocatalyst for Urea Synthesis from Nitrogen and Carbon Dioxide Fixation:A Computational Study

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Energy & Env.ronmental Materials 2024年第1期7卷 207-214页

作者： Dongxu Jiao Zhongxu Wang Yuejie Liu Qinghai Cai Jingxiang Zhao carlos R.Cabrera Zhongfang Chen College of Chemistry and Chemical Engineering and Key Laboratory of Photonic and Electronic Bandgap Materials Ministry of EducationHarbin Normal UniversityHarbin 150025China Modern Experiment Center Harbin Normal UniversityHarbin 150025China Heilongjiang Prov.nce Collaborativ. Innov.tion Center of Cold Region Ecological Safety Harbin 150025China Department of Chemistry and Biochemistry The University of Texas at El PasoEl Paso TX 79968USA Department of Chemistry University of Puerto RicoRio Piedras CampusSan JuanPuerto Rico 00931USA

Urea synthesis through the simultaneous electrocatalytic reduction of N_(2)and CO_(2)molecules under ambient conditions holds great promises as a sustainable alternativ. to its industrial production,in which the dev.lopment of stable,highly efficient,and highly selectiv. catalysts to boost the chemisorption,activ.tion,and coupling of inert N_(2)and CO_(2)molecules remains rather ***,by means of density functional theory computations,we proposed a new class of two-dimensional nanomaterials,namely,transition-metal phosphide monolayers(TM_(2)P,TM=Ti,Fe,Zr,Mo,and W),as the potential electrocatalysts for urea *** results showed that these TM_(2)P materials exhibit outstanding stability and excellent metallic ***,the Mo_(2)P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier(0.35 ev.for C-N coupling,low limiting potential(-0.39 v.,and significant suppressing effects on the competing side *** outstanding catalytic activ.ty of the Mo_(2)P monolayer can be ascribed to its optimal adsorption strength with the key^(*)NCON species due to its moderate positiv. charges on the Mo activ. *** findings not only propose a nov.l catalyst with high-efficiency and high-selectiv.ty for urea production but also further widen the potential applications of metal phosphides in electrocatalysis.

关键词： C-N coupling density functional theory Mo_(2)P monolayer urea synthesis

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基于艺术治疗方法的护理干预在边缘型人格障碍患者中的应用

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International Journal of Nursing Sciences 2024年第2期11卷 205-213页

作者： Ana Morales-alonso Angela Iglesias-de-la-Iglesia Miriam alonso-Maza Dr.Rodríguez Lafora Hospital(Hospital Dr.Rodríguez Lafora) MadridSpain Department of Nursing and Stomatology University Rey Juan CarlosAlcorconMadridSpain

目的ZentangleR艺术治疗方法被应用于心理健康相关领域,尚未在边缘型人格障碍患者得到验证。本研究分析边缘型人格障碍患者接受ZentangleR艺术治疗方法的练习体验。方法采用现象学解释方法,对患者进行半结构化访谈。患者均已在西班牙某... 详细信息

目的ZentangleR艺术治疗方法被应用于心理健康相关领域,尚未在边缘型人格障碍患者得到验证。本研究分析边缘型人格障碍患者接受ZentangleR艺术治疗方法的练习体验。方法采用现象学解释方法,对患者进行半结构化访谈。患者均已在西班牙某医院的人格障碍治疗室接受了每个月1次,共6次ZentangleR艺术治疗。本研究中共访谈了15例患者。Smith、Flowers和Larkin方法用于资料分析中的评估。结果根据研究结果,共提炼出3个类别的主题:有耕耘即有收获(参与者报告了注意力、放松、人际关系、与环境互动方面的改善,以及接受和改变的积极体验);众擎易举(患者认可在团体中感觉更好,并建立了相互联系;他们也描述了团体环境对个人行为的影响);画出自己的轨迹(通过绘画方式提供了自我表达和自我认识的媒介,通过情感表达提升了幸福感,提高了创造力,增强了自信心)。结论通过练习ZentangleR,患者可以作出灵活性和适应性等行为反应,通过焦虑管理、冲动控制改善情绪健康,学习应对问题,提高自尊或注意力。心理健康护理在边缘型人格的综合治疗及协同多样化补充性干预措施中发挥着积极作用。

关键词：艺术治疗边缘型人格障碍心理健康护理 Zentangle®

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Sociodemographic determinants associated with breastfeeding in term infants with low birth weight in Latin American countries

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World Journal of Clinical Pediatrics 2024年第1期13卷 141-149页

作者： carlos Jav.er Av.ndaño-v.squez Magda Liliana v.llamizar-Osorio Claudia Jazmin Niño-Peñaranda Judith Medellín-Olaya Nadia Carolina Reina-Gamba School of Nursing Antonio Nariño UniversityBogotá111511Colombia School of Nursing Universidad Cooperativa de ColombiaBucaramanga 102536Colombia School of Nursing Universidad Nacional de ColombiaColombia 111511Colombia

BACKGROUND A progressiv. decrease in exclusiv. breastfeeding(BF)is observ.d in Latin America and the Caribbean compared with global *** possibility of being breastfed and continuing BF for>6 months is lower in low birth weight than in healthy-weight *** To identify factors associated with BF maintenance and promotion,with particular attention to low-and middle-income countries,by studying geographic,socioeconomic,and indiv.dual or neonatal health *** A scoping rev.ew was conducted in 2018 using the conceptual model of social determinants of health published by the Commission on Equity and Health Inequalities in the United *** extracted data with common characteristics were synthesized and categorized into two main themes:(1)Sociodemographic factors and proximal determinants inv.lv.d in the initiation and maintenance of BF in low-birth-weight term infants in Latin America;and(2)indiv.dual characteristics related to the self-efficacy capacity for BF maintenance and adherence in low-birth-weight term *** This study identified maternal age,educational lev.l,maternal economic capacity,social stratum,exposure to BF substitutes,access to BF information,and quality of health serv.ces as mediators for maintaining *** Indiv.dual self-efficacy factors that enable BF adherence in at-risk populations should be analyzed for better health outcomes.

关键词： Breastfeeding Low birth weight Latin America Self-efficacy Social determinants of health

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How to fill the biodiv.rsity data gap:Is it better to inv.st in fieldwork or curation?

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Plant Div.rsity 2024年第1期46卷 39-48页

作者： carlos A.v.rgas Marius Bottin Tiina Sarkinen James E.Richardson Marcela Celis Boris v.llanuev. Adriana Sanchez Programa de Biología Facultad de Ciencias NaturalesUniversidad del RosarioBogotaD.C.Colombia Subdireccion Científica Jardín Botanico de Bogota“Jose Celestino Mutis”BogotaD.C.Colombia Independent Researcher BogotaD.C.Colombia Tropical Div.rsity Section Royal Botanic Garden EdinburghUK School of Biological Earth and Environmental SciencesUniversity College CorkCorkIreland Departamento de Química y Biología Universidad del NorteKm.5 Vía Puerto ColombiaArea Metropolitana de Barranquilla 081007Colombia

Data gaps and biases are two important issues that affect the quality of biodiv.rsity information and downstream *** how best to fill existing gaps and account for biases is necessary to improv. our current information most *** current main approaches for obtaining and improv.ng data include(1)curation of biological collections,and(2)***,the comparativ. effectiv.ness of these approaches in improv.ng biodiv.rsity data remains little *** used the Flora de Bogota project to study the magnitude of change in species richness,spatial cov.rage,and sample cov.rage of plant records based on curation v.rsus *** process of curation resulted in a decrease in species richness(synonym and error remov.l),but it significantly increased the number of records per *** contributed to a slight increase in species richness,v.a accumulation of new ***,curation led to increases in spatial cov.rage,species observ.d by locality,the number of plant records by species,and localities by species compared to ***,curationwas more efficient in producing new information compared to fieldwork,mainly because of the large number of records av.ilable in *** recommend intensiv. curatorial work as the first step in increasing biodiv.rsity data quality and quantity,to identify bias and gaps at the regional scale that can then be targeted with *** stepwise strategy would enable fieldwork to be planned more costeffectiv.ly giv.n the limited resources for biodiv.rsity exploration and characterization.

关键词： Colombia Flora de Bogota Sample cov.rage Species richness Tropical Andes

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Complexed amino acid minerals v.. bis-glycinate chelated minerals:Impact on the performance of old laying hens

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Animal Nutrition 2024年第1期16卷 395-408页

作者： Marcos J.B.Santos Maria C.M.M.Ludke Leandro M.Silv. carlos B.v.Rabello Mércia R.Barros Fabiano S.Costa Clariana S.Santos Jamille S.S.Wanderley Department of Animal Science Rural Federal University of Pernambuco Department of v.terinary Science Rural Federal University of Pernambuco

The present study was to ev.luate the effect of trace minerals(Zn, Mn, and Cu) from complexed amino acid minerals(ZMCAA) and bis-glycinate chelated minerals(ZMCGly) in laying hen diets on performance,internal and external egg quality, yolk mineral deposition, intestinal morphometry, and bone characteristics. From 78 to 98 weeks of age, 400 White LSL-Lite strain laying hens were distributed in a randomized design with 4 treatments with 10 replicates per treatment. Treatments were distributed in a 2 ×2 factorial arrangement using either Zn, Mn, and Cu of ZMCAA or ZMCGly source at 2 lev.ls: low(20, 20,and 3.5 mg/kg of Zn, Mn, and Cu, respectiv.ly) or high(40, 40, and 7 mg/kg of Zn, Mn, and Cu,respectiv.ly). The analysis of v.riance was performed, and in cases where differences were observ.d, the means were compared using Tukey?s test(P v.l of trace mineral supplementation had a significant impact on the performance of laying hens. Hens fed ZMCAA had higher egg production(P = 0.01), egg weight(P = 0.02), egg mass(P = 0.01), and lower feed conv.rsion ratio(P =0.05) compared to those fed ZMCGly. The ZMCAA supplementation showed higher albumen height(P =0.01), albumen weight(P = 0.01), and eggshell thickness(P v.d ZMCAA. Tibia weight(P = 0.04)and bone densitometry(P v.lli(P = 0.02) and shorter crypt depth(P = 0.01) in the *** and ileum measurements were influenced by the lev.l and source of trace minerals(P v.ls demonstrated adequate lev.ls of supplementation.

关键词： Bis-glycinates Metal-amino acids Radiodensity Trace minerals

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