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Mineralogical signatures and sources of recent sediment in a large tropical lake

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International Journal of Sediment Research 2018年第2期33卷 183-190页

作者： Jorge Feliciano Ontiveros-Cuadras ana carolina ruiz-fernández Joan-Albert Sanchez-Cabeza Libia Hascibe Pérez-Bernal Michel Preda Federico Páez-Osuna Polytechnic University of Sinaloa (UPSIN) Mazatlan Academic Unit Institute of Marine Sciences and LimnologyNational Autonomous University of Mexico (UNAM) Oceanic and Coastal Processes Academic Unit Institute of Marine Sciences and LimnologyNational Autonomous University of Mexico (UNAM).University City Department of Earth and Atmospheric Sciences University of Quebec in Montreal (UQAM)

Two lead-210(210Pb) dated sediment cores from Chapala Lake were studied to identify the mineral composition of the sediments and to discuss its relation with trace metals. Minerals and trace metals reflected the domain of volcanic rocks(i.e. basalts, rhyolite and andesite) that characterize Chapala Lake and the Lerma River watershed. Redundancy analyses(RDA) were used to identify the sedimentary variables(magnetic susceptibility, organic matter, sand content, and mineral composition) that could be related to elemental composition. Despite the distance between the two cores(7.3 km) and hydrodynamic circulation the RDA showed that the main mechanism that controls the input of mineral species,and, therefore, element distributions in the lacustrine sediment of Chapala Lake, is related to the weathering of volcanic rocks in the Lerma-Chapala watershed, the consequent runoff and transport of fine grained catchment materials, and later in-lake processes. These findings highlight the importance of controlling watershed erosion to contribute to the improvement of the environmental quality of the lake.

关键词： Chapala Lake Trace metals Mineralogy Lacustrine sediments

Resilience to structural and molecular changes in excitatory synapses in the hippocampus contributes to cognitive function recovery in Tg2576 mice

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Neural Regeneration Research 2024年第9期19卷 2068-2074页

作者： carolina Aguado Sara Badesso JoséMartínez-Hernández Alejandro Martín-Belmonte Rocío Alfaro-ruiz Miriam fernández ana Esther Moreno-Martínez Mar Cuadrado-Tejedor ana García-Osta Rafael Luján Synaptic Structure Laboratory Instituto de Investigación en Discapacidades Neurológicas(IDINE)Department of Medical SciencesFacultad de MedicinaUniversidad de Castilla-La ManchaCampus BiosanitarioAlbaceteSpain Gene Therapy for Neurological Disease Program Center for Applied Medical Research(CIMA)University of NavarraInstituto de Investigación Sanitaria de Navarra(IdiSNA)PamplonaSpain Pharmacology Unit Department of Pathology and Experimental TherapeuticsFaculty of Medicine and Health SciencesInstitute of NeurosciencesUniversity of BarcelonaBarcelonaSpain Neuropharmacology and Pain Group Neuroscience ProgramInstitut d’InvestigacióBiomèdica de BellvitgeIDIBELLL’Hospitalet de LlobregatSpain Department of Pathology Anatomy and PhysiologySchool of MedicineUniversity of NavarraPamplonaSpain UniversitéGrenoble Alpes Grenoble Institut des NeurosciencesGrenobleFrance

Plaques of amyloid-β(Aβ)and neurofibrillary tangles are the main pathological characteristics of Alzheimer’s disease(AD).However,some older adult people with AD pathological hallmarks can retain cognitive *** the factors that lead to this cognitive resilience to AD offers promising prospects for identifying new therapeutic *** hypothesis focuses on the contribution of resilience to changes in excitatory synapses at the structural and molecular levels,which may underlie healthy cognitive performance in aged AD *** the Morris Water Maze test,we selected resilient(asymptomatic)and cognitively impaired aged Tg2576 *** the enzyme-linked immunosorbent assay showed similar levels of Aβ42 in both experimental groups,western blot analysis revealed differences in tau pathology in the pre-synaptic supernatant *** further investigate the density of synapses in the hippocampus of 16-18 month-old Tg2576 mice,we employed stereological and electron microscopic *** findings indicated a decrease in the density of excitatory synapses in the stratum radiatum of the hippocampal CA1 in cognitively impaired Tg2576 mice compared with age-matched resilient Tg2576 and non-transgenic ***,through quantitative immunoelectron microscopy in the hippocampus of impaired and resilient Tg2576 transgenic AD mice,we uncovered differences in the subcellular localization of glutamate ***,the density of GluA1,GluA2/3,and mGlu5 in spines and dendritic shafts of CA1 pyramidal cells in impaired Tg2576 mice was significantly reduced compared with age-matched resilient Tg2576 and non-transgenic ***,the density of GluA2/3 in resilient Tg2576 mice was significantly increased in spines but not in dendritic shafts compared with impaired Tg2576 and non-transgenic *** subcellular findings strongly support the hypothesis that dendritic spine plasticity and synaptic machinery in the hippocampus play cr

关键词： aging Alzheimer´s disease cognitive hippocampus immunoelectron microscopy resilience synapse

Historical fluxes of metal and metalloids in an aquatic ecosystem affected by land-use change and mining activities in northwestern Mexico

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International Journal of Sediment Research 2023年第5期38卷 724-738页

作者： Ochoa-Contreras Roberto Jara-Marini Martín Enrique ruiz-fernández ana carolina Sanchez-Cabeza Joan Albert Meza-Figueroa Diana Pérez-Bernal Libia Hascibe Posgrado en Ciencias Centro de Investigación en Alimentación y Desarrollo Unidad Hermosillo 2. Centro de Investigación en Alimentación y Desarrollo Unidad Hermosillo Unidad Acad emica Mazatlán Instituto de Ciencias del Mar y Limnología Universidad Nacional Autónoma de M exico Departamento de Geología División de Ciencias Exactas y Naturales Universidad de Sonora Rosales y Encinas

Freshwater reservoirs are essential owing because of their ecological, economic, and social *** are particularly vulnerable to contamination, as of metal and metalloids, derived from anthropogenic activities like mining. The temporal variations in trace element concentrations(arsenic(As),mercury(Hg), chromium(Cr), copper(Cu), nickel(Ni), lead(Pb), and zinc(Zn)), enrichment, fluxes, and possible sources were evaluated by studying two sediment cores from the La Angostura(ANG) Reservoir(northwest Mexico), using210Pb geochronology. The enrichment factors showed from null to minor enrichment for most elements, but moderate to severe enrichment of mercury(Hg). Most trace element concentrations had a detrital origin, and notable Hg concentration increases since the past decade were associated with severe drought periods, likely resulting from wildfires. The observed sediment concentrations of As and Hg can cause adverse effects on biota in the ecosystem since they are above the probable effect level(PEL). Development of strategies for metal attenuation in this reservoir is recommended and metals should be controlled until specific ecotoxicological studies are performed.

关键词： Aquatic ecosystems ~(210)Pb geochronology Mining activities Metals Metalloids Enrichment factors

Chemical and spectroscopic characterization of humic substances from sediment and riparian soil of a highly polluted urban river(Suquía River,Córdoba,Argentina)

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International Journal of Sediment Research 2020年第3期35卷 287-294页

作者： carolina Merlo carolina Vázquez ana Graciela Iriarte Carlos Matías Romero Instituto Multidisciplinario de Biologia Vegetal (CONICET) Facultad de Ciencias Agropecuarias Universidad Nacional de Cordoba INFIQC Departament of FisicoquimicaFacultad de Ciencias QuimicasUniversidad Nacional de Cordoba Agriculture and Agri-Food Canada Lethbridge Research and Development Centre Department of Biological Sciences University of Lethbridge

The Suquia River,the largest urban river in Cordoba(Argentina),has been severely polluted for *** must be taken to restore its environmental quality by managing riparian zones for increased water-self *** current study aimed to characterize organic matter(OM) dynamics and humic substances(HS) spectrochemical properties along the lower-middle basin of the Suquia *** soil(0-20 cm) and sediment(0-10 cm) samples were collected from a reference location(S1)and four polluted sites(S2-S5) during a low-flow *** contents of soil and sedimentary OM and HS fractions were analyzed by wet oxidation,as well as HS Fourier transform infrared(FT-IR) and ultraviolet-visible(UV-Vis) spectrochemical *** OM and HS fractions from riparian soil were high upstream of Cordoba City(S1 and S2,50.2-50.4 g/kg OM) and within a 50 km downstream location(S5,30.9 g/kg OM) owing to a surplus of fresh plant biomass-carbon(C) *** heterogeneous sediment samples did not show any significant differences among sites(P> 0.05).The lowest values of the ratio of absorbances at 465 and 665 nm(E4/E6)(1.78) and the Δ log K(0.15) coefficient(a measure of HS maturity degree) were obtained downstream of Cordoba City,for both riparian soil and sediment,indicating that HS were enriched by more condensed aromatic structures within highly degraded portions of the *** samples exhibited similar IR spectra,implying overlapping recalcitrant-C structures at the functional group level,but with different absorbance *** from the current study constitute a baseline for understanding the chemical nature of HS from sediment and riparian soil along the Suquia River and can be used as a reference for future studies tracking OM compositional changes over time.

关键词： Lotic ecosystems Organic matter Humic acids FT-IR spectroscopy UV-Vis spectroscopy

Evaluation of a Pointwise Local Visual Pattern Exploration Method

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Tsinghua Science and Technology 2012年第4期17卷 429-439页

作者： Matthew O.Ward Elke A.Rundensteiner carolina ruiz Department of Computer Science Worcester Polytechnic InstituteWorcesterMA 01609USA

Sensitivity analysis is a powerful method for discovering the significant factors that contribute to understanding the interaction between variables in multivariate datasets. A number of sensitivity analysis methods fall into the class of local analysis, in which the sensitivity is defined as the partial derivatives of a target variable with respect to a group of independent variables. In a recent paper, we presented a novel pointwise local pattern exploration system for visual sensitivity analysis. Using this system, analysts are able to explore local patterns and the sensitivity at individual data points, which reveals the relationships between a focal point and its neighbors this paper we present several evaluations of the system, including case studies with real datasets, user studies the effectiveness of the visualizations and interactions, and a detailed description of the experience of a user In on

关键词： knowledge discovery sensitivity analysis local pattern visualization evaluation

Tropical dendrochronology applied to invasive tree species in the Brazilian Atlantic Forest

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Journal of Forestry Research 2021年第1期32卷 91-101页

作者： carolina Nogueira Xavier Daniela Granato-Souza ana carolina M.C.Barbosa JoséReinaldo Moreira da Silva Forest Sciences Department Federal University of Lavras(UFLA)C.P.3037Lavras 37200-000Brazil Department of Geosciences University of ArkansasFayettevilleAR 72701USA

The Atlantic Forest is one of the largest and most biodiverse rainforests of South America but anthropogenic activities are drastically changing these *** invasion of alien or exotic species is one of the greatest threats to *** are few studies of invasive species in tropical Brazilian *** research examines growth and ecological aspects of Syzygium cumini and Clitoria fairchildiana,two invasive tree species in the Pedra Branca State Park,an Atlantic Forest remnant in southeastern *** species were successfully dated,indicating an average age of 58 and 31 years,respectively.A positive relationship between growth and precipitation of the previous growing season suggests an ecological adaptive strategy,which could be facilitating their invasion into the *** growth diameter curves indicate slow and fast growth rates for *** and ***,*** release episodes detected in the tree rings indicate increased anthropogenic disturbances over the last 50 years.

关键词： Atlantic Forest biome Invasive species Protected areas Tree rings

Early detection of tomato bacterial canker by reflectance indices

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Information Processing in Agriculture 2022年第2期9卷 184-194页

作者： Gabriela Cordon carolina Andrade Lucia Barbara ana Maria Romero Universidad de Buenos Aires Consejo Nacional de Investigaciones Cientı´ficas y Te´cnicasInstituto de Investigaciones Fisiolo´gicas y Ecolo´gicas Vinculadas a la Agricultura(IFEVA)Facultad de Agronomı´aBuenos AiresArgentina Universidad de Buenos Aires Facultad de Agronomı´aA´rea de Educacio´n AgropecuariaBuenos AiresArgentina Universidad de Buenos Aires Facultad de Agronomı´aCa´tedra de Fitopatologı´aBuenos AiresArgentina

Early detection of infected asymptomatic plants could prevent the dissemination of tomatobacterial canker throughout the crop and, thus, reduce associated economic losses. Reflectance spectroscopy has been proposed for the detection of diseases in plants, mainlycaused by foliar fungal pathogens. In contrast, bacterial canker is a vascular disease thatdoes not produce visible foliar symptoms until it is too late to avoid contagion to otherplants. The effects of the disease on the conductivity of the xylem have an impact onthe water content of the leaves;initially, a subtle effect that cannot be assessed with thenaked eye but can be evaluated by reflectance spectroscopy. The objective of this workwas to identify indices, based on the reflectance spectral signature of the plants, for thedetection of tomato plants affected by bacterial canker prior to the appearance of symptoms. To verify that the proposed methodology is applicable to a broad range of tomatogenotypes, two experiments were carried out with different tomato cultivars grown in potsand another on the ground in a greenhouse. Plants were inoculated with the pathogenicbacteria and the reflectance spectrum of the apical leaflet of two leaves per plant wereobtained before symptoms expression;several spectral indices were calculated from thereflectance spectra. Three indices, of the shortwave-infrared zone, allowed the detectionof bacterial canker inoculated plants in a fast and non-destructive way, up to one weekbefore symptoms were visible: Normalized Difference Water Index (NDWI), Simple Ratioof Water Index (SRWI) and Water Index 1 180 (WI1180). Our research demonstrates, forthe first time, the usefulness of spectral indices sensitive to water content for the identifi-cation of diseased plants. These indices arise as a promising tool for the early detection ofvascular plant diseases, that could be integrated into sustainable management plans.

关键词： Clavibacter michiganensis subsp. michiganensis Bacterial wilt Reflectance indices Solanum lycopersicum L

Proactive reconciliation as a tool for integrating mining and milling operations

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International Journal of Mining Science and Technology 2019年第2期29卷 239-244页

作者： ana carolina Chieregati Luiz Eduardo Campos Pignatari Francis fernand Pitard Homero Delboni Jr Department of Mining and Petroleum Engineering University of Sao Paulo EDEM Engenharia Mineral Francis Pitard Sampling Consultants

Historically, reconciliation has been viewed as a quality test of model estimates as well as a powerful tool for detecting and correcting problems in all stages of mine operations from resource estimation to metal production. If used correctly, reconciliation helps to better predict the life of mine(LOM), improves the adherence of production plans to the respective budget, and allows for effective control of the mining and milling processes. However, the accuracy of reconciliation results requires that all input data must be generated in accordance with the principles of sampling correctness. Furthermore, complete reconciliation systems can become extremely complex and must be carefully analyzed in order to provide realistic and helpful conclusions. Based on these concepts, this paper presents a successful proactive reconciliation system applied to a copper and gold mine in Brazil for monitoring and integrating mining and milling operations.

关键词： Reconciliation Prognostication Sampling Gold Copper

Adsorption of neodymium,terbium and dysprosium using a synthetic polymer-based magnetic adsorbent

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Journal of Rare Earths 2023年第11期41卷 1796-1804,I0006页

作者： Hamedreza Javadian Mehdi Taghavi Montserrat ruiz Inderjeet Tyagi Majid Farsadrooh ana Maria Sastre Department of Chemical Engineering ETSEIBUniversitat Politècnica de CatalunyaDiagonal 64708028BarcelonaSpain Department of Chemistry Faculty of ScienceShahid Chamran University of Ahvaz61357-43337Iran Department of Chemical Engineering EPSEVGUniversitat Politècnica de CatalunyaAv.Víctor Balaguers/n08800Vilanova i la GeltrúSpain Centre for DNA Taxonomy Molecular Systematics DivisionZoological Survey of IndiaKolkata700053India Renewable Energies Research Laboratory Department of ChemistryFaculty of ScienceUniversity of Sistan and BaluchestanP.O.Box 98135674ZahedanIran

In this study,a polyamide with methine-thiophene and pyrimidine linkages(poly(pyrimidine-thiophene-amide)(PPTA))was ***,magnetic PPTA(M-PPTA)was synthesized using the hydrothermal *** products were analyzed by Fourier-transform infrared spectroscopy(FTIR),nuclear magnetic resonance(NMR),X-ray diffraction(XRD),thermogravimetric analysis(TGA),field-emission scanning electron microscopy(FE-SEM),and a vibrating-sample magnetometer(VSM).The nanocomposite exhibits a saturation magnetization of 50.44 emu/g recorded by VSM *** ability of M-PPTA to bind dysprosium(Dy^(3+)),terbium(Tb^(3+)),and neodymium(Nd^(3+))was *** 0.15 g of M-PPTA to test the adsorption of the rare earth elements(50 mg/L)at pH=5.5,the percentage of adsorption for Dy^(3+),Tb^(3+),and Nd^(3+)is 98.41%,97.48%and 95.67%,***-second-order(PSO)significantly fits the adsorption kinetic *** equation was used to describe the adsorption equilibrium data of Dy^(3+)and Tb^(3+),while Langmuir model was used to simulate Nd^(3+)adsorption *** the temperature leads to an increase in the performance of M-PPTA,and an endothermic adsorption process was confirmed by the positive values ofΔ*** four adsorption-desorption cycles,the efficiency of adsorption of Dy^(3+),Tb^(3+),and Nd^(3+)by M-PPTA is88.75%,86.37%,and 84.64%,*** antagonism effect is observed for the adsorption of the individual ions in a ternary solution.

关键词： Polyamide Lanthanides Magnetic nanocomposite Adsorption Rare earth elements