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Activities of liquid fe-As and fe-Sb alloys saturated with carbon

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rare Metals 2006年第5期25卷 488-491页

作者： leandro Voisin Kimio Itagaki Institute of Multidisciplinary research for Advanced Materials Tohoku UniversitySendai 980-8577Japan

A solid iron base alloy of the so-called furnace residue is often formed as a by-product in reduction smelting of lead sinter and scraps with high contents of arsenic and antimony. The use of phase separation into a liquid iron-rich alloy and a liquid lead-rich alloy in lead-iron-arsenic and lead-iron-antimony systems saturated with carbon at relatively low temperatures of about 1200~C was proposed in a new process for treating the fumace residue to recover valuable elements into the lead-rich alloy and fLx toxic arsenic into the iron-rich alloy. As a fundamental study for the proposed process, the activity coefficients and interaction parameters of the fe-As and fe-Sb systems saturated with carbon at 1200℃ were derived in this study, based on the determined phase relations in the fe-Pb-As and fe-Pb-Sb systems saturated with carbon.

关键词： activity coefficient phase relations Pb-fe-As-C system Pb-fe-Sb-C system lead-smelting lead-recycling

Senescent mesenchymal stem/stromal cells in pre-metastatic bone marrow of untreated advanced breast cancer patients

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oncology research 2023年第3期31卷 361-374页

作者： FraNCISCo raÚL BoRZoNE MARÍA BELÉN GIoreLLo leandro MARCELo MARTINEZ MARÍA CECILIA SANMARTIN LEoNARDo feLDMAN feDERICo DIMASE EMILIo BATAGELJ GUSTAVo YANNAreLLI NoRMA ALEJANDra CHASSEING Laboratorio de Inmunohematología Instituto de Biología y Medicina Experimental(IBYME)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Buenos AiresArgentina Division of Hematology and Medical oncology Department of MedicineWeill Cornell Medical CollegeNew YorkUSA Laboratorio de regulación Génica y Células Madre Instituto de Medicina TraslacionalTrasplante y Bioingeniería(IMeTTyB)Universidad Favaloro-CONICETBuenos AiresArgentina Facultad de Ciencias de la Salud Universidad Nacional del Centro de la Provincia de Buenos Aires(UNCPB)TandilBuenos AiresArgentina Servicio de Hematología Hospital Militar CentralBuenos AiresArgentina Servicio de oncología Hospital Militar CentralBuenos AiresArgentina

Breast cancer is the predominant form of carcinoma among women worldwide,with 70%of advanced patients developing bone metastases,with a high mortality *** this sense,the bone marrow(BM)mesenchymal stem/stromal cells(MSCs)are critical for BM/bone homeostasis,and failures in their functionality,transform the BM into a premetastatic niche(PMN).We previously found that BM-MSCs from advanced breast cancer patients(BCPs,infiltrative ductal carcinoma,stage III-B)have an abnormal *** work aims to study some of the metabolic and molecular mechanisms underlying MSCs shift from a normal to an abnormal profile in this group of patients.A comparative analysis was undertaken,which included self-renewal capacity,morphology,proliferation capacity,cell cycle,reactive oxygen species(RoS)levels,and senescence-associatedβ‑galactosidase(SA‑β‑gal)staining of BMderived MSCs isolated from 14 BCPs and 9 healthy volunteers(HVs).Additionally,the expression and activity of the telomerase subunit TERT,as well as telomere length,were *** levels of pluripotency,osteogenic,and osteoclastogenic genes(oCT-4,SoX-2,M-CAM,RUNX-2,BMP-2,CCL-2,M-CSF,and IL-6)were also *** results showed that MSCs from BCPs had reduced,self-renewal and proliferation *** cells also exhibited inhibited cell cycle progression and phenotypic changes,such as an enlarged and flattened ***,there was an increase in RoS and senescence levels and a decrease in the functional capacity of TERT to preserve telomere *** also found an increase in pro-inflammatory/pro-osteoclastogenic gene expression and a decrease in pluripotency gene *** conclude that these changes could be responsible for the abnormal functional profile that MSCs show in this group of patients.

关键词： Mesenchymal stem/stromal cells Senescence Breast cancer Bone marrow Pre-metastatic niche Bone metastasis

Particulate matter geochemistry of a highly industrialized region in the Caribbean:Basis for future toxicological studies

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Geoscience Frontiers 2022年第1期13卷 376-387页

作者： Luis F.o.Silva Ismael L.Schneider Paulo Artaxo Yuleisy Núñez-Blanco Diana Pinto Érico M.M.Flores leandro Gómez-Plata omar ramírez Guilherme L.Dotto Department of Civil and Environmental Universidad de la CostaCUCCalle 58#55–66BarranquillaAtlánticoColombia Department of Applied Physics Institute of PhysicsUniversity of São PauloBrazil Department of Chemistry Universidade Federal de Santa MariaRSBrazil Universidad Militar Nueva Granada(UMNG) Faculty of EngineeringEnvironmental EngineeringKm 2 Cajicá-ZipaquiráColombia Chemical Engineering Department Federal University of Santa Maria-UFSM1000Roraima Avenue97105-900 Santa MariaRSBrazil

Air pollution has become an important issue,especially in Caribbean urban areas,and,particulate matter(PM)emitted by different natural and anthropogenic sources causes environmental and health *** this work,we studied the concentrations of PM_(10) and PM_(2.5) sources in an industrial and port urban area in the Caribbean region of *** samples were collected within 48-h periods between April and october 2018 by using a Partisol 2000 i-D *** geochemical characterization was performed by X-ray fluorescence(XRF)***,ionic species and black carbon(BC)were quantified by ion chromatography and reflectance spectroscopy,*** the Positive Matrix Factorization(PMF)receptor model,the contributions of PM sources were *** average concentration of PM_(10) was 46.6±16.2μg/m^(3),with high concentrations of Cl and *** PM_(2.5),the average concentration was 12.0±3.2μg/m^(3),and the most abundant components were BC,S,and *** receptor model identified five sources for PM_(10) and PM_(2.5).For both fractions,the contributions of marine sea spray,re-suspended soil,and vehicular traffic were *** addition,PM_(2.5) included two mixed sources were found to be fuel oil combustion with fertilizer industry emissions,and secondary aerosol sources with building construction ***,PM_(10) was found to also include building construction emissions with re-suspended soil,and metallurgical industry *** obtained geochemical atmospheric results are important for the implementation of strategies for the continuous improvement of the air quality of the Caribbean region.

关键词： Urban air pollution Particulate matter Geochemical composition Aerosol source apportionment receptor models PMF

Dual-Delay-Path Ring oscillator with Self-Biased Delay Cells for Clock Generation

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Circuits and Systems 2023年第6期14卷 19-28页

作者： Agord de Matos Pinto Jr raphael Ronald Noal Souza Mateus Biancarde Castro Eduardo Rodrigues de Lima leandro Tiago Manêra School of Electrical and Computer Engineering (feEC) University of Campinas Campinas Brazil Eldorado research Institute Campinas Brazil

This work summarizes the structure and operating features of a high-performance 3-stage dual-delay-path (DDP) voltage-controlled ring oscillator (VCRo) with self-biased delay cells for Phase-Locked Loop (PLL) structurebased clock generation and digital system driving. For a voltage supply VDD = 1.8 V, the resulting set of performance parameters include power consumption PDC = 4.68 mW and phase noise PN@1MHz = -107.8 dBc/Hz. From the trade-off involving PDC and PN, a system level high performance is obtained considering a reference figure-of-merit ( FoM = -224 dBc/Hz ). Implemented at schematic level by applying CMoS-based technology (UMC L180), the proposed VCRo was designed at Cadence environment and optimized at MunEDA WiCkeD tool.

关键词： Phase Locked Loop (PLL) Voltage-Controlled Ring oscillators (VCRo) Dual-Delay-Path DDP Delay Cells

In vitro adherence of conjunctival bacteria to different oculoplastic materials

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International Journal of ophthalmology(English edition) 2018年第12期11卷 1895-1901页

作者： Alvaro Toribio Honorina Martinez-Blanco leandro Rodriguez-Aparicio Miguel A.ferrero Teresa Marrodán Isabel fernández-Natal Department of ophthalmology University Hospital of Leon Leon 24071Spain Department of Molecular Biology University of LeonLeon 24071Spain Department of Clinical Microbiology University Hospital of LeonLeon 24071Spain

AIM: To investigate the resistance to bacterial adhesion of materials used in oculoplastic surgery, particularly materials used in the manufacture of orbital ***: Seven organisms of conjunctival flora(two strains of Staphylococcus epidermidis and one strain each of Staphylococcus aureus, Staphylococcus hominis, Corynebacterium amycolatum, Acinetobacter calcoaceticus, and Serratia marcescens) were selected. A lactic acid bacterium(Lactobacillus rhamnosus) was also included as positive control because of its well-known adhesion ability. Eight materials used to make oculoplastic prostheses were selected(glass, steel, polytetrafluoroethylene, polymethylmethacrylate, silicone from orbital implants, commercial silicone, porous polyethylene, and semismooth polyethylene). Materials surfaces and biofilms developed by strains were observed by scanning electron microscopy. Kinetics of growth and adhesion of bacterial strains were determined by spectrophotometry. Each strain was incubated in contact with plates of the different materials. After growth, attached bacteria were re-suspended and colony-forming units(CFUs) were counted. The number of CFUs per square millimetre of material was statistically ***: A mature biofilm was observed in studied strains except Staphylococcus hominis, which simply produced a microcolony. Materials showed a smooth surface on the microbial scale, although steel exhibited 1.0-μm-diameter grooves. Most organisms showed significant differences in adhesion according to the material. There were also significant differences in thetotal number of CFUs per square millimetre from each material(P=0.044). CFU counts were significantly higher in porous polyethylene than in silicone from orbital implants(P=0.038).CoNCLUSIoN: Silicone orbital implants can resist microbial colonization better than porous polyethylene implants.

关键词： conjunctival flora microbial adhesion biofilm orbital implant oculoplastic prosthesis

Proximal sensor-enhanced soil mapping in complex soil-landscape areas of Brazil

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Pedosphere 2021年第4期31卷 615-626页

作者： Sérgio H.G.SILVA David C.WEINDoRF Wilson M.FARIA leandro C.PINTo Michele D.MENEZES Luiz R.G.GUILHERME Nilton CURI Department of Soil Science Federal University of LavrasLavras 37200-000(Brazil) Department of Earth and Atmospheric Sciences Central Michigan UniversityMount Pleasant 48858(USA)

Portable X-ray fluorescence(pXRF) spectrometry and magnetic susceptibility(MS) via magnetometer have been increasingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many countries with tropical soils. The objective of this study was to use proximal soil sensor data associated with terrain variables at varying spatial resolutions to predict soil classes using the random Forest(RF) algorithm. The study was conducted on a 316-ha area featuring highly variable soil classes and complex soil-landscape relationships in Minas Gerais State, Brazil. The overall accuracy and Kappa index were evaluated using soils that were classified at 118 sites, with 90 being used for modeling and 28 for validation. Digital elevation models(DEMs) were created at 5-, 10-, 20-, and 30-m resolutions using contour lines from two sources. The resulting DEMs were processed to generate 12 terrain variables. Total fe, Ti, and Sio_(2) contents were obtained using pXRF, with MS determined via a magnetometer. Soil class prediction was performed using the RF algorithm. The quality of the soil maps improved when using only the five most important covariates and combining proximal sensor data with terrain variables at different spatial resolutions. The finest spatial resolution did not always provide the most accurate maps. The high soil complexity in the area prevented highly accurate predictions. The most important variables influencing the soil mapping were MS, fe, and Ti. Proximal sensor data associated with terrain information were successfully used to map Brazilian soils at variable spatial resolutions.

关键词： magnetic susceptibility magnetometer portable X-ray fluorescence spectrometer soil class soil spatial analysis spatial resolution terrain variables

The lncRNA APoLo interacts with the transcription factor WRKY42 to trigger root hair cell expansion in response to cold

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Molecular Plant 2021年第6期14卷 937-948页

作者： Michael Moison Javier Martinez Pacheco leandro Lucero Camille Fonouni-Farde Johan Rodriguez-Melo Natanael Mansilla Aurelie Christ Jeremie Bazin Moussa Benhamed fernando Ibanez Martin Crespi Jose M.Estevez federico Ariel Instituto de Agrobiotecnología del Litoral Universidad Nacional del LitoralCONICETFBCB/FHUCCentro Científico Tecnológico CONICET Santa FeColectora Ruta Nacional No 168 km.0Paraje El PozoSanta Fe 3000Argentina Fundación Instituto Leloir and IIBBA-CoNICET Av.Patricias Argentinas 435Buenos Aires CP C1405BWEArgentina Instituto de Investigaciones Agrobiotecnológicas CONICETUniversidad Nacional de Río CuartoRío Cuarto 5800Argentina Institute of Plant Sciences Paris-Saclay(IPS2) CNRSINRAUniversity Paris-Saclay and University of Paris Bâtiment 63091192 Gif sur YvetteFrance Centro de Biotecnología Vegetal(CBV) Facultad de Ciencias de la Vida(FCsV)Universidad Andres BelloSantiagoChile and Millennium Institute for Integrative Biology(iBio)SantiagoChile

Plant long noncoding RNAs(lncRNAs)have emerged as important regulators of chromatin dynamics,impacting on transcriptional programs leading to different developmental *** lncRNA AUXIN-reGULATED PRoMoTER LooP(APoLo)directly recognizes multiple independent loci across the Arabidopsis genome and modulates their three-dimensional chromatin conformation,leading to transcriptional ***,we show that APoLo recognizes the locus encoding the root hair(RH)master regulator RooT HAIR DEfeCTIVE 6(RHD6)and controls RHD6 transcriptional activity,leading to cold-enhanced RH elongation through the consequent activation of the transcription factor gene RHD6-like ***,we demonstrate that APoLo interacts with the transcription factor WRKY42 and modulates its binding to the RHD6 ***42 is required for the activation of RHD6 by low temperatures and WRKY42 deregulation impairs cold-induced RH ***,our results indicate that a novel ribonucleoprotein complex with APoLo and WRKY42 forms a regulatory hub to activate RHD6 by shaping its epigenetic environment and integrate signals governing RH growth and development.

关键词： root hairs long noncoding RNAs APoLo RHD6 WRKY42 cold temperature

Synthesis and evaluation of nickel cobalt ferrite magnetic ceramics employing two alternative routes

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Journal of Advanced Dielectrics 2021年第3期11卷 2-7页

作者： Javier E.Camargo leandro A.ramajo Miriam S.Castro División Cerámicos INTEMA Instituto de Investigaciones en Ciencia y Tecnología de Materiales(INTEMACONICET-UNMdP)Av.Colón 108507600Mar del PlataArgentina

Ni_(0.5)Co_(0.5)fe_(2)o_(4)(NCF)powders were obtained employing two alternative synthesis routes:solid-state reaction and Pechini’s *** ceramic powders were pressed and sintered in the temperature range of 1100℃ to 1250℃.Microstructural and structural properties were evaluated by SEM,XRD,and raman *** hysteresis loops of sintered samples were also recorded.A secondary phase was observed in samples synthesized by Pechini’s method,whereas samples obtained by the solid-state reaction method,with the mechanochemical activation of the reagents,only produced the spinel *** properties of samples obtained by the solid-state method displayed higher magnetic saturations and lower coercive fields than those obtained from the Pechini’s method.

关键词： ferrite Pechini raman spectroscopy magnetic properties

Spatial and temporal distribution of the gastropod Heleobia australis in an eutrophic estuarine system suggests a metapopulation dynamics

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Natural Science 2010年第8期2卷 860-867页

作者： Carlos Alejandro Echeverría raquel A. F. Neves leandro A. Pessoa Paulo C. Paiva 不详

Hydrobiidae is one of the most diverse taxa among limnic and estuarine mollusks. Patterns of spatial and seasonal distribution of Heleobia australis were studied in ten stations over two years, in the urban eutrophic bay of Guanabara, Rio de Janeiro, Brazil. Spatial dispersal strategies in adults of this species, analyzed in the laboratory, revealed three patterns: 1) mobility on soft sediments;2) mobility on hard substrata;and 3) the ability to lift from the bottom to the surface, to again sink down. This facilitate species movement from one location to another by surface currents or attached to floating debris. Thus, individuals are able to escape from an impacted area and further re-colonize other patches after recovering from local impacts. The hypothesis of metapopulation dynamics (source– sink) was analyzed. Two stations with high and constant numbers of individuals were grouped and tested as possible ‘sources’. The number of specimens in the remaining stations was highly variable, even with the complete disappearance and posterior highly dense re-occurrence of the mollusk, whereby these were tested as possible ‘sinks’. results derived from nested ANoVA supported the hypothesis of metapopulation dynamics in the case of H. australis adults, ex-pressed through opportunistic-species domi- nation of a highly impacted estuarine system, such as Guanabara Bay.

关键词： Metapopulation Benthic Macrofauna Population Dynamics Heleobia Australis Guanabara Bay