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Fast synthesis of gold nanoparticles by cold atmospheric pressure plasma jet in the presence of Au^(+) ions and a capping agent

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Plasma Science and Technology 2024年第7期26卷 108-115页

作者： Tatiana HABIB josé mauricio.a.caiut Bruno CAILLIER Laboratoire Diagnostics des Plasmas Hors Equilibre(DPHE) Universitéde ToulouseINU ChampollionAlbi 81000France Department of Chemistry The Nanomaterials and Luminescent Systems GroupFaculty of PhilosophyScience and Letters at Ribeirão PretoUniversity of São PauloRibeirão Preto-SP 14040-901Brazil

Homogeneous gold nanoparticles were synthesized under atmospheric pressure using a nonthermal helium plasma jet in a single-step process.A current power supply was used to generate the plasma discharge rich in diverse reactive *** species induce rapid chemical reactions responsible for the reduction of the gold salts upon contact with the liquid *** this study,spherical and monodispersed gold nanoparticles were obtained within 5 min of plasma exposure using a solution containing gold(Ⅲ)chloride hydrate(HAuCl_(4))as a precursor and polyvinylpyrrolidone(PVP)as a capping agent to inhibit *** formation of these metal nanoparticles was initially perceptible through a visible change in the sample's color,transitioning from light yellow to a red/pink *** was subsequently corroborated by UVvis spectroscopy,which revealed an optical absorption in the 520-550 nm range for Au NPs,corresponding to the surface plasmon resonance(SPR)*** investigation into the impact of various parameters,including plasma discharge duration,precursor and capping agent concentrations,was carried out to optimize conditions for the formation of well-separated,spherical gold *** light scattering(DLS)was used to measure the size of these nanoparticles,transmission electron microscopy(TEM)was used to observe their morphology and X-ray diffraction(XRD)was also employed to determine their crystallographic *** results confirm that homogeneous spherical gold nanoparticles with an average diameter of 13 nm can be easily synthesized through a rapid,straightforward,and environmentally friendly approach utilizing a helium atmospheric pressure plasma.

关键词： gold nanoparticles non-thermal plasma jet helium DBD

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Impact of STAT-signaling pathway on cancer-associated fibroblasts in colorectal cancer and its role in immunosuppression

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1705-1724页

作者： Damián Sánchez-Ramírez Mónica G Mendoza-Rodríguez Omar R Alemán Fernando A Candanedo-González Miriam Rodríguez-Sosa Juan joséMontesinos-Montesinos mauricio Salcedo Ismael Brito-Toledo Felipe Vaca-Paniagua Luis I Terrazas Unidad de Investigacion en Biomedicina Facultad de Estudios Superiores IztacalaUniversidad Nacional Autonoma de MexicoTlalnepantla 54090Estado de MexicoMexico Department of Biology Facultad de QuimicaUniversidad Nacional Autonoma de MexicoCiudad UniversitariaMexico City 04510Mexico Department of Pathology National Medical Center Century XXIInstituto Mexicano del Seguro SocialMexico City 06720Mexico Laboratorio de Células Troncales Mesenquimales Unidad de Investigación Médica en Enfermedades OncológicasHospital de Oncología Centro Medico Nacional Siglo XXIInstituto Mexicano del Seguro SocialMexico City 06720Mexico Unidad de Investigacion en Biomedicina y Oncologia Genomica Instituto Mexciano del Seguro SocialMexico City 07300Mexico Servicio de Colon y Recto Hospital de Oncología Centro Medico Nacional Siglo XXIInstituto Mexicano del Seguro SocialMexico City 06720Mexico Laboratorio Nacional en Salud Facultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla 54090Estado de MexicoMexico

Colorectal cancer(CRC)remains one of the most commonly diagnosed and deadliest types of cancer *** displays a desmoplastic reaction(DR)that has been inversely associated with poor prognosis;less DR is associated with a better *** reaction generates excessive connective tissue,in which cancer-associated fibroblasts(CAFs)are critical cells that form a part of the tumor *** are directly involved in tumorigenesis through different ***,their role in immunosuppression in CRC is not well understood,and the precise role of signal transducers and activators of transcription(STATs)in mediating CAF activity in CRC remains *** the myriad chemical and biological factors that affect CAFs,different cytokines mediate their function by activating STAT signaling ***,the harmful effects of CAFs in favoring tumor growth and invasion may be modulated using STAT ***,we analyze the impact of different STATs on CAF activity and their immunoregulatory role.

关键词： Cancer-associated fibroblasts Signal transducer and activator of transcription signaling Colorectal cancer Immunity Immunosuppression

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Relict glacial landscape in the Sierra Baguales Mountain Range(50°-51°S):evidence of glaciation dynamics and types in the eastern foothills of the southern Patagonian Andes

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Journal of Mountain Science 2017年第2期14卷 282-295页

作者： ARAOS.joséMiguel LE ROUX.Jacobus Philiphus GUTIERREZ.Néstor mauricio Department of Geology FCFMUniversidad de ChilePlaza Ercilla#803SantiagoChile Department of Geography Faculty of Social Sciences.Universidad Alberto HurtadoUienfuegos#41SantiagoChile Department of Geology FCFMUniversidad de Chile.Andean Geothermal Centre of ExcellencePlaza Ereilla#803SantiagoChile

The glacial morphology of southern South American presents invaluable evidence to reconstruct former glacier behaviour and its relation to climate and environmental changes. However, there are still spatial and temporal gaps in the reconstruction of the Holocene Patagonian glacial landscape. Here we present the first geomorphological record for the Sierra Baguales Mountain Range(SBMR), forming the eastern foothills of the Southern Patagonian Andes 200 km from the Pacific coast. This area is topographically isolated from the Southern Patagonian Ice Field(SPIF), and is affected by the Westerly Winds. The study area shows evidence of ice sheet and alpine glaciations related to Andean uplift,which caused a marked climatic contrast between its western and eastern flanks since the Last Glacial Maximum(LGM). The regional rock mass strength and precipitation gradient acted as a controlling factor in the glacial cirque distribution and sizes, as well as in the development of glaciation types. We report new radiocarbon dates associated with warm/dry to cold/wet climatic changes during the middle Holocene, when former small alpine glaciers were located in the uppermost section of the SBMR basins, and eventually converged to form a small ice field or a composite valley glacier at lower *** can be explained by an estimated regional temperature drop of 3.8°C±0.8°C, based on a 585±26m Equilibrium Line Altitude(ELA) descent, inferred by geomorphological evidence and the Accumulation Area Ratio(AAR), in addition to a free-air adiabatic lapse rate. Subsequently, the glaciers receded due to climatic factors including a rise in temperature, as well as non-climatic factors, mainly the glacier bedrock topography.

关键词： Glacial morphology Sierra Baguales Ice sheet glaciations Alpine glaciations Middle Holocene

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Gain of transcription factor binding sites is associated to changes in the expression signature of human brain and testis and is correlated to genes with higher expression breadth

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Science China(Life Sciences) 2019年第4期62卷 526-534页

作者： Vandeclécio Lira da Silva André mauricio Ribeiro dos Santos Wilfredo Blanco Sandro josé de Souza Bioinformatics Multidisciplinary Environment (BioME) Universidade Federal do Rio Grande do Norte (UFRN) Programa de Pós-Gradua??o em Genética e Biologia Molecular (PPGBM) Universidade Federal do Pará (UFPA) Department of Computer Science Universidade Estadual do Rio Grande do Norte (UERN) Brain Institute Universidade Federal do Rio Grande do Norte (UFRN)

The gain of transcription factor binding sites(TFBS) is believed to represent one of the major causes of biological *** we used strategies based on comparative genomics to identify 21,822 TFBS specific to the human lineage(TFBS-HS),when compared to chimpanzee and gorilla genomes. More than 40%(9,206) of these TFBS-HS are in the vicinity of 1,283 genes.A comparison of the expression pattern of these genes and the corresponding orthologs in chimpanzee and gorilla identified genes differentially expressed in human tissues. These genes show a more divergent expression pattern in the human testis and brain, suggesting a role for positive selection in the fixation of TFBS gains. Genes associated with TFBS-HS were enriched in gene ontology categories related to transcriptional regulation, signaling, differentiation/development and nervous ***, genes associated with TFBS-HS present a higher expression breadth when compared to genes in general. This biased distribution is due to a preferential gain of TFBS in genes with higher expression breadth rather than a shift in the expression pattern after the gain of TFBS.

关键词： TFBS transcript factor human evolution expression breadth

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Virtual Conductance Based Cascade Voltage Controller for VSCs in Islanded Operation Mode

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1704-1713页

作者： Francisco Jesús Matas-Díaz Manuel Barragán-Villarejo Juan Carlos Olives-Camps Juan Manuel mauricio joséMaría Maza-Ortega Department of Elec‐trical Engineering Universidad de SevillaSeville 41092Spain

Voltage source converters have become the main enabler for the integration of distributed energy resources in *** the case of islanded operation,these devices normally set the amplitude and frequency of the network voltage by means of a cascade controller composed of an outer voltage control loop and an inner current control *** strategies to compute the gains of both control loops have been proposed in the literature in order to obtain a fast and decoupled response of the voltages at the point of common *** paper proposes an alternative and simple methodology based on the introduction of a virtual conductance in the classic cascade *** strategy allows to design each control loop independently,obtaining a closed-loop response of a first-order *** this way,the gains of each control loop are easily derived from the parameters of the LC coupling filter and the desired closed-loop time ***,a state observer is included in the controller to estimate the inductor current of the LC filter in order to reduce the number of required measurements.A laboratory testbed is used to validate and compare the proposed *** experimental results demonstrate the effectiveness of the proposal both in steady-state and transient regimes.

关键词： Voltage source converter microgrid cascade controller virtual conductance

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Solar Driven Wind Speed Monitoring System Using Wireless or Wired Sensors

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Energy and Power Engineering 2014年第9期6卷 213-221页

作者： Federico Hahn mauricio Pablo josé Reyes Department of Irrigation Universidad Autonoma Chapingo Texcoco México

Instrumented towers are being constructed to characterize vertical wind profiles in order to improve the understanding and characterization of a desired environment up to 100 m. The site being measured is at a height of 2500 m over sea level, in one side of Sierra Madre Oriental, which crosses Mexico from North to South. As the site has no energy, it was powered by a photovoltaic system. Power consumption of two sets of sensors fixed at the tower was evaluated. The first sensor set consisted of a pulsed anemometer and a RH sensor having a 0 - 10 V output;these sensors used cables for transmitting the output signals. Three cup anemometers fixed at 25, 35 and 45 m high measured wind speed. Wireless sensors in the second set, requires of a power consumption and battery life study. Solar cells energized the sensors, becoming the installation and operation easier. The datalogger that acquired the RH and T measurements encountered an 11% voltage loss throughout the cable;cup anemometer measurements did not show variations due to its pulsed signals. Wireless sensors drew less energy from the PV system, resulting in battery overcharge. A dump regulator turned-on a 200 W lamp during the night when the battery voltage reached 14 V;the lamp was turned-off when the battery voltage felt beneath 11.5 V. Considering the high wind available, wireless sensors batteries were charged by small wind turbines combined with 5 W solar panels.

关键词： Wind Tower Wireless Anemometers Battery Regulator

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Correlation length around Mars:A statistical study with MEX and MAVEN observations

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Earth and Planetary Physics 2019年第6期3卷 560-569页

作者： Adriane Marques de Souza Franco Markus Franz Ezequiel Echer mauricio joséAlves Bolzan National Institute for Space Research(INPE) Sao Jose dos CamposBrazil Max Planck Institute for Solar System Research GoettingenGermany Federal University of Jataí JataíBrazil

Correlation lengths of ultra-low-frequency(ULF)waves around Mars were computed for the first time,using data from MEX(electron density from 2004 to 2015)and MAVEN(electron density and magnetic field from 2014 to 2016).Analysis of the MEX data found that,for the frequency range 8 to 50 mHz,correlation length in electron density varied between 13 and 17 seconds(temporal scale)and between 5.5×10^3 km and 6.8×10^3 km(spatial scale).For the MAVEN time interval,correlation length was found to vary between 11 and 16 seconds(temporal scale)and 2×10^3–4.5×10^3 km in spatial *** the magnetic field data,correlation lengths are observed to be between 8–15 seconds(temporal scale)and between 1×10^3 and 5×10^3 km(spatial scale)over the same frequency *** observe that the cross sections of the plasma regions at the dayside of Mars are smaller than these correlation lengths in these regions in both analyses,where the correlation length derived from the MEX electron density data was between 5 and 25 times the size of the magnetosheath and the magnetic pile-up region(MPR),*** MAVEN these ratios are about 4(magnetosheath)and 11(MPR)in electron density and between 1.5 and 5.5 for magnetic field data,*** results indicate that waves at the magnetosheath/MPR can be related to oscillations in the upper *** a local region,wave trains may cause resonance effects at the planetary ionopause,which consequently contributes to the enhanced ion escape from the atmosphere.

关键词： Mars induced magnetosphere ULF waves correlation length

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What is the prognosis of emphysematous pyelonephritis associated with extended-spectrum beta-lactamases producing microorganisms?

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Asian Journal of Urology 2022年第2期9卷 146-151页

作者： joséIván Robles-Torres Marco Alberto Ocaña-Munguía joséGustavo Arrambide-Herrera Adrián mauricio Martínez-Fernández Rodrigo Romero-Mata Lauro Salvador Gómez-Guerra Urology Department Hospital Universitario"Dr.Jose´Eleuterio Gonza´lez"Universidad Auto´noma de Nuevo LeonMonterreyNuevo LeonMexico

Objective:To describe the microbiological characteristics in emphysematous pyelonephritis(EPN),demonstrate the frequency of extended-spectrum beta-lactamase(ESBL)microorganisms,and determine if these microorganisms are associated with the prognosis of patients with ***:We conducted a retrospective study in patients with a diagnosis of EPN in a tertiary care hospital of the northeast region of Mexico during the period from January 2011 to January *** variables were analyzed to determine association with the presence of ESBL-producing *** significance was set with p<***:A total of 63 patients were included;55(87.3%)of them were females,with a median age of 55(interquartile range:45-65)*** management was indicated in 38.1%;42.9%were treated with ureteral stent;12.7%with open or percutaneous drainage;15.8%with early nephrectomy;and 9.5%with delayed *** mortality was 13(20.6%)cases;23(36.5%)cases required admission to the intensive care *** most frequent microorganism isolated was Escherichia coli(n=34,53.9%).ESBL microorganisms were found in 31.7%of the *** significant association of ESBL was found with admission to the intensive care unit,or with increased ***:To our knowledge,this is the first study that evaluates ESBL microorganisms as a prognostic factor in *** factors associated with a poor prognosis in patients with EPN have been *** microbiological factors,specifically ESBL-producing bacteria,do not seem to influence in the prognosis of these patients.

关键词： Emphysematous pyelonephritis Extended spectrum betalactamase Mortality Intensive care unit admission

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Small river basin and estuarine sediment fluxes:The magnitude necessary for coastal dispersion and siltation effects on a coral reef

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International Journal of Sediment Research 2019年第6期34卷 591-599页

作者： Paula Sagili?o Isacksson Eduardo Guilherme Gentil de Farias Francisco josé Dias Roberto Nascimento de Farias Anandra Machado Francisco de Assis Esteves mauricio Mussi Molisani Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ) Universidade Federal do Rio de Janeiro Grupo de Gestao Ecologia e Tecnologia Marinha (GTMar)Departamento de Engenharia de Pesca a Ciencias Biologicas (DEPB)Universidade do Estado de Santa Catarina (UESC) Laboratorio de Hidrodinamica Costeira Estuarina e de Aguas Interiores (LHiCEAI)Departamento de Oceanografia e Limnologia (DEOLI)Universidade Federal do Maranhao (UFMA) Programa de Pos-Graduacao em Ciencias Ambientais e Conservacao-PPGCIAC Instituto de Biodiversidade e Sustentabilidade (NUPEM/UFRJ)

Increasing continental suspended sediment influx to coral reefs is an example of land-sea coupling that requires the identification of sources,magnitude of transport,and controlling *** Brazil,a small coastal basin(Macae River) was identified as a source of suspended sediment to a coral reef on the coast of Cape Armacao dos *** suspended sediment loads were measured at the basin as were fluxes within the estuary and towards the coast during eight tidal *** load and yield from this basin were typical of small coastal basins,showing high to moderate slopes and transitional land ***,the magnitude of the river loads was lower than the sediment transport within the estuary,indicating that the estuary amplifies river fluxes and sustains the transference of suspended sediment alongshore to the coral ***,the estuary displays both suspended particle retention and export capacity and,therefore,fluxes to the coast and the coral reef occur as episodic events.

关键词： Suspended matter Watershed Mass-balance budget Campos Basin

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Tropical tree community composition and diversity variation along a volcanic elevation gradient

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Journal of Mountain Science 2022年第12期19卷 3475-3486页

作者： Ruben MARTINEZ-CAMILO Manuel MARTINEZ-MELENDEZ Nayely MARTINEZ-MIELENDEZ Derio Antonio JIMENEZ-LOPEZ mauricio josE-RIOS Unidad Villa Corzo Facultad de IngenieríaUniversidad de Ciencias y Artes de Chiapas30520 Villa CorzoChiapasMexico Instituto de Ciencias Biológicas Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico Eizia A.C. 29045 Tuxtla GutiérrezChiapasMexico Departamento de Conservación de la Biodiversidad El Colegio de la Frontera Sur29290 San Cristóbal de las CasasChiapasMexico Orquidiario y Jardín Botánico de Comitán Secretaría de Medio Ambiente e Historia Natural30106 Comitán de DomínguezChiapasMexico Instituto de Investigación en Gestión de Riesgos y Cambio Climático Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico

Unraveling the factors that determine variation of diversity in tropical mountain systems is a topic for debate in plant *** is especially true in areas where topography is complex due to volcano elevational gradients and where forests are vulnerable to human *** this study we used a set of climatic(temperature,rainfall,and radiation solar),topographic(elevation,slope aspect,and slope orientation)and human disturbance variables to determine their effect on diversity and composition patterns of a tree community,considering three slope aspects of a tropical volcano in southeastern *** sampled trees in seventy 0.1-ha plots distributed on three slope aspects of the Tacanávolcano along an elevational gradient of 1500 to 2500 *** determined diversity patterns(general tree richness,exponential of Shannon index,and pioneer species richness)with linear regression models,and for beta diversity,we used a dissimilarity index(within and between elevational bands 100 m wide).The effect of a set of environmental and human disturbance variables on tree diversity and community composition was analyzed with general linear models and multivariate analyses,*** registered 2,949 individual trees belonging to 176 species and *** average species richness and alpha diversity per plot were 13(standard deviation±6)and 9(±5),*** tree richness and alpha diversity increased in the middle part(unimodal patterns)of the elevational gradient,but pioneer species richness decreased linearly with *** variance explained by general linear models was greater in richness(32%)than in alpha diversity(25.3%).The most important predictor variables were temperature(elevational gradient),which explained the unimodal pattern(richness and alpha diversity increase at intermediate levels of temperature),and slope orientation,which explained the increase in richness and alpha diversity toward the geographic *** temperature had a signific

关键词： Composition Environmental gradient Tree diversity patterns Tropical humid cloud forest Tropical volcanoes

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