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Estimation of Low Nutrients in Tomato Crops Through the Analysis of Leaf Images Using Machine Learning

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Journal of Artificial Intelligence and Technology 2021年第2期1卷 131-137页

作者： Hiram Ponce Claudio Cevallos Ricardo Espinosa Sebastián gutiérrez Universidad Panamericana Facultad de IngenieríaAugusto Rodin 498Ciudad de México 03920México Universidad Panamericana Facultad de IngenieríaJosemaría Escriváde Balaguer 101Aguascalientes 20290México

Tomato crops are considered the most important agricultural products ***,the quality of tomatoes depends mainly on the nutrient *** inspection is made by farmers to anticipate the nutrient deficiency of the ***,precision agriculture has explored opportunities to automate nutrient level *** work has demonstrated that a convolutional neural network is able to estimate low nutrients in tomato plants using images of their ***,the performance of the convolutional neural network was not ***,this work proposes a novel convolutional neural network-based classifier,namely,CNN+AHN,for estimating low nutrients in tomato crops using an image of the tomato *** CNN+AHN incorporates a set of convolutional layers as the feature extraction part,and a supervised learning method called artificial hydrocarbon network as the dense *** combinations of the architecture of CNN+AHN were *** results showed that our best CNN+AHN classifier is able to estimate low nutrients in tomato plants with an accuracy of 95.57%and F1-score of 95.75%,outperforming the literature.

关键词： agriculture image processing deep learning computer vision color analysis

Study of reverse osmosis membranes fouling by inorganic salts and colloidal particles during seawater desalination

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Chinese Journal of Chemical Engineering 2020年第3期28卷 733-742页

作者： Santiago gutiérrez Ruiz Juan Antonio López-Ramírez Mohammed Hassani Zerrouk Agata Egea-Corbacho Lopera JoséMaría Quiroga Alonso Department of Environmental Technologies Faculty of Marine and Environmental SciencesUniversity of Cadiz11510Puerto RealCadizSpain

Fouling phenomenon is considered among the major reasons that cause significant increase of operating cost of desalination plants equipped with reverse osmosis(RO)*** phenomenon is studied in the present work in the case of RO polyamide aromatic membranes using model seawater containing inorganic salts and colloidal *** solubility conditions of CaCO3 and CaSO4 were applied to study RO performances with and without colloid *** experiments,the membrane permeate fluxes were continuously ***,studies of chemical composition,structure,and morphology of the materials deposited on the membrane surface were conducted using energy dispersive microanalysis(EDS)X-ray diffraction and scanning electronic microscopy(SEM).Results show that in conditions of calcium carbonate oversaturation there is a reduction in the permeate flow of 11.2%due to fouling of the membrane by the precipitation of this *** in the same conditions of calcium sulphate oversaturation the reduction of the flow is 5%,so we can conclude that in conditions of oversaturation of both salts,calcium carbonate produces a greater fouling of the membrane that in its view causes greater decrease in the flow of *** this based on the results of the test with both salts in oversaturated *** in the formation of calcite and gypsum crystals onto the membranes as XRD analyses *** presence of colloidal silica in those conditions intensifies strongly the fouling,leading until to 24.1%of permeate flux decrease.

关键词： Reverse osmosis Desalination Fouling Seawater Scaling

Roller Screw and Threaded Chain Speed Reducer: An Experimental Evaluation

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Modern Mechanical Engineering 2024年第1期14卷 1-11页

作者： Filiberto gutiérrez Instituto de Ingeniería Universidad Nacional Autónoma de México Mexico City Mexico

We are developing a speed reducer that can be considered a transformation of a worm gear reducer: the worm is replaced by an inverted roller screw, and the gear is replaced by a threaded chain drive. This configuration lessens wear, increases load capacity, and improves efficiency. The threaded chain consists of nut-shaped links. This paper presents the results of tests carried out on a prototype with a reduction ratio of 46.

关键词： Speed Reducer Inverted Roller Screw Chain Drive Threaded Chain Drive

Surface Properties of Fe_4N Compounds Layer on AISI 4340 Steel Modified by Pulsed Plasma Nitriding

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Journal of Materials Science & Technology 2013年第3期29卷 287-290页

作者： J.C.Díaz-Guillén G.Vargas-gutiérrez E.E.Granda-gutiérrez J.S.Zamarripa-Pia S.I.Pérez-Aguilar J.Candelas-Ramírez L.lvarez-Contreras Centro de Investigacin en Materiales Avanzados S.C.Miguel de Cervantes 120Complejo Industrial ChihuahuaC.P.31109 ChihuahuaChihuahuaMexico Corporacin Mexicana de Investigacin en Materiales S.A.de C.V.Ciencia y Tecnología No 790Fracc.Saltillo 400C.P.25290 SaltilloCoahuilaMexico Centro de Investigacin y Estudios Avanzados del IPN Unidad SaltilloCarretera Saltillo Monterrey km 13Apdo.Postal 663C.P.25000 SaltilloCoahuilaMexico

In this work, the effect of nitriding current density on hardness, crystalline phase composition, layer thickness and corrosion rate of AlSl 4340 steel has been studied. X-ray diffraction analysis shows that thin layers formed during nitriding process are constituted of 7-Fe4N for samples processed between 1 and 2.5 mA/cm2. Thickness of nitrided layer increases proportionally to current density （0 μm for 0.5 mA/cm2 to 15 pm for 2.5 mA/cm2）. Plasma nitriding increased the surface hardness from 300 HV50g for untreated sample, to around 800HV5og for nitrided samples at 1 mA/cm2. While the untreated samples exhibited a corrosion rate of 0.153 mm per year, the corrosion performance was improved up to 0.03 mm per year at current densities above 1 mA/cm2, which is about one fifth of the corrosion rate of the untreated sample.

关键词： Plasma nitriding Current density Hardness Corrosion

Rice Husk Bio-Chars as Adsorbent for Methylene Blue and Ethinylestradiol from Water

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Journal of Renewable Materials 2020年第3期8卷 275-287页

作者： Jonathan Lacuesta Iris Beatriz Vega Erramuspe Liji Sobhana Dennis Kronlund Jouko Peltonen Soledad gutiérrez Pedro Fardim Department of Chemical Engineering University of the RepublicJulio Herrera y Reissig 565Montevideo11300Uruguay Laboratory of Fibre and Cellulose Technology Åbo Akademi UniversityPorthansgatan 3Turku/ÅboFI-20500Finland Laboratory of Physical Chemistry and Center of Excellence for Functional Materials Åbo Akademi UniversityPorthansgatan 3Turku/ÅboFI-20500Finland Department of Chemical Engineering KU LeuvenCelestijnenlaan 200FLeuvenB-3001Belgium

Biobased adsorbents are eco-friendly materials used for water and wastewater treatment and air *** research work explores the potential use of rice husk chars as a low-cost adsorbent for pollutants from water,such as methylene blue and *** husk chars are prepared by combustion of rice husks(RH-Char)or pre-treated rice husks(PT-Char).A third char(M-Char)supplied by a local company which uses rice husks as combustion material is also *** chars are characterized by field emission scanning electron microscopy(FE-SEM)in conjunction with energy dispersive X-ray spectroscopy(EDX),X-ray powder diffraction(XRD),and zeta-potential *** three bio-chars are tested as adsorbent for the removal of two wastewater contaminants:methylene blue(MB)and ethinylestradiol(EE2).According to the results,RH-Char and PT-Char present zeta-potential values near−52 mV,whereas M-Char shows a zeta-potential value of−32 *** RH-Char and PTChar are rich in amorphous SiO_(2) and M-Char has crystalline SiO_(2)(cristobalite).The bio-chars remove MB and EE2 efficiently showing the following results for the adsorption capacity of MB(inμmol g^(−1)):769.2(RH-Char),41.2(PT-Char),and 31.7(M-Char).The adsorption capacity values for EE2(inμmol g^(−1))are:33.1(RH-Char),19.1(PT-Char),and 16.9(M-Char).The information gathered in the present work evidences the potential of rice husks bio-chars for bio-remediation and may in future contribute to the conversion of a side-stream from the rice industry into value-added materials.

关键词： Rice husk bio-char thermal treatment adsorption methylene blue ethinylestradiol

The Effect of Water and Salt Stress on Paspalum dilatatum,a Constituent of Pampas Natural Grasslands

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 2009-2018页

作者： Claudia A.Porcelli Gerardo Rubio Flavio H.gutiérrez Boem Raul S.Lavado Departamento de Química Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresC1417DSEArgentina Instituto de Investigaciones en Biociencias Agricolas y Ambientales(INBA) Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresC1417DSEArgentina

The effects of the salt stress on plant growth are usually increased by the water *** studied the impact of both stresses in simultaneous pulses of drought and salinity on Paspalum *** forage species is native to South America,spread in grasslands in many tropical,subtropical,and temperate areas of the world,and very common in grasslands of the Flooding Pampas of *** what happens in *** compared a pot experiment,a non-stressed control against water stress for a month(midpoint between field capacity and wilting point),and two saline stresses(moderate,6 d·Sm^(−1)and strong,12 d·Sm^(−1)),also for a *** biomass(green leaf;non-leaf green material,and dry material)and roots were harvested,weighed,and analyzed for nitrogen,phosphorus,and *** biomass of all components significantly decreased when both stresses were *** plus strong saline stress reduced by half the total biomasses,compared to the *** proportion of aerial biomass/root biomass ratio as well as aerial green component/dry materials ratio tend to decrease when subjected to both *** concentration in plants was not significantly affected,but phosphorus concentration increased in aerial biomass components,from 0.10 to 0.18 mg·kg^(−1)between the extreme treatments,but did not change in *** concentration in plants increased(i.e.,in green leave sodium(Na)increased from 0.27 to 2.01 mg·kg^(−1)between the extreme treatments),whereas other cations either did not change or decreased,affecting the ratios between *** performance allows us to infer that the Na accumulation of *** behaves in an intermediate range,compared to very tolerant to salts or non-salt tolerant species of the Paspalum *** agreement,when salts were applied in the form of a pulse,*** tolerated higher salinity than that found by other authors for the same species,using continuous salinity.

关键词： Dallis grass salinity drought sodium in plants phosphorus in plants potassium/sodium ratio

c-Abl kinase at the crossroads of healthy synaptic remodeling and synaptic dysfunction in neurodegenerative diseases

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Neural Regeneration Research 2023年第2期18卷 237-243页

作者： Daniela A.gutiérrez América Chandía-Cristi María JoséYáñez Silvana Zanlungo Alejandra R.Alvarez Cell Signaling Laboratory Department of Cellular and Molecular BiologyCenter for Aging and Regeneration(CARE)Millennium Institute on Immunology and ImmunotherapyBiological Sciences FacultyPontificia Universidad Católica de ChileSantiagoChile School of Medical Technology Health Sciences FacultyUniversidad San SebastianSede Los LeonesSantiagoChile Department of Gastroenterology Faculty of MedicinePontificia Universidad Católica de ChileSantiagoChile

Our ability to learn and remember depends on the active formation,remodeling,and elimination of ***,the development and growth of synapses as well as their weakening and elimination are essential for neuronal *** structural reorganization of synaptic complexes,changes in actin cytos keleton and organelle dynamics,as well as modulation of gene expression,determine synaptic *** has been proposed that dys regulation of these key synaptic homeostatic processes underlies the synaptic dysfunction observed in many neurodegenerative *** is known about downstream signaling of activated N-methyl-D-aspartate andα-amino-3-hydroxy-5-methyl-4-isoazolepro pionate receptors;howeve r,other signaling pathways can also contribute to synaptic plasticity and long-lasting changes in learning and *** non-receptor tyrosine kinase c-Abl(ABL1)is a key signal transducer of intra and extracellular signals,and it shuttles between the cyto plasm and the *** review focuses on c-Abl and its synaptic and neuronal ***,we discuss the evidence showing that the activation of c-Abl can be detrimental to neurons,promoting the development of neurodegenerative ***,c-Abl activity seems to be in a pivotal balance between healthy synaptic plasticity,regulating dendritic spines remodeling and gene expression after cognitive training,and synaptic dysfunction and loss in neurodegenerative ***,c-Abl genetic ablation not only improves learning and memory and modulates the brain genetic program of trained mice,but its absence provides dendritic spines resiliency against *** re,the present review has been designed to elu cidate the common links between c-Abl regulation of structural changes that involve the actin cytos keleton and organelles dynamics,and the transc riptional program activated during synaptic *** summarizing the recent discove ries on c-Abl functions,we aim to provide an overview of how

关键词： actin cytoskeleton activity-dependent plasticity Alzheimer's disease c-Abl dendritic spines learning synapse synaptic plasticity transcription tyrosine kinase

Resource economics and coordination among above- and below-ground functional traits of three dominant shrubs from the Chilean coastal desert

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Journal of Plant Ecology 2015年第1期8卷 70-78页

作者： Joaquín Morales Francisco A.Squeo Yann Tracol Cristina Armas Julio R.gutiérrez Facultad de Ciencias Universidad de La SerenaCasilla 554La SerenaChile Institute of Ecology and Biodiversity(IEB) Casilla 653SantiagoChile Center of Advanced Studies in Arid Zones Casilla 554La SerenaChile

Aims Plant functional traits determine how plants respond to environmen-tal factors and influence ecosystem *** them,root traits and analyses of relations between above and below-ground traits in natural communities are *** we characterized a set of above-and below-ground traits of three dominant shrub species in a semiarid shrub-steppe that had contrasting leaf pheno-logical habits(deciduous,semideciduous and evergreen).We ana-lysed if there was coordination among above-and below-ground resource economics patterns:*** of biomass allocation,construction costs and *** Findings Above-and below-ground traits and their resource economics relations pointed to species-specific functional strategies to cope with drought and poor soils and to a species ranking of fast to slow whole-plant strategies in terms of resource uptake,biomass con-struction costs and *** deciduous shrub,Proustia cunei-folia,had relatively deep and even distribution of roots,and high proportion of short-lived tissues of low C construction costs:it had high fine to coarse root and high leaf-to-stem biomass ratios,high specific leaf area(SLA),and stems of low wood *** strat-egy allows Proustia to maximize and coordinate above-and below-ground resources uptake as long as the most limiting factor(water)is available,but at the cost of having relative high plant biomass *** evergreen Porlieria chilensis,instead,displayed a more conservative and slow strategy in terms of resource *** had~80%of the roots in the 40 cm topsoil profile,low pro-portion of fine compared with coarse roots and low leaf-to-stem ratios,low SLA and stems of high wood density,*** invested in C costly tissues that,overall,persist longer but probably at the cost of having lower plant resource uptake *** in the semide-ciduous Adesmia bedwellii were in between these two functional *** results revealed high functional diversity and above-

关键词： drought functional diversity mass fractions root distribution specific leaf area

THE SUMERIAN TERM u_(8)/ud_(5)/ab_(2)/eme_(3)/_(6)sila_(4)/maš_(2)/amar du_(3)(-a)

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Journal of Ancient Civilizations 2024年第1期39卷 1-28,123页

作者： Marcos Such-gutiérrez Facultad de Filosofía y Letras Universidad Autónoma de Madrid

The aim of the present article is twofold:firstly,to prove that the expression animal+young du_(3)(-a),which is basically documented in texts from the 3rd millennium BC,refers to a dam that has just given birth,and se... 详细信息

关键词： 3rd millennium BC female animal+young du_(3)(-a) livestock newborn suckling animal UrⅢperiod