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Characterization of Arroyo Verde Epithermal Deposit:Paragenesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower Chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： Cecilia Pavón Pivetta Leonardo Benedini Paulo Marcos Ma.agustina Cócola Mercedes Virginia Barros Daniel Gregori Leonardo Strazzere Anderson Costa dos Santos Mauro C.Geraldes Instituto Geologico del Sur(INGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nacional de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is located within the Lower Chon Aike volcanism and is developed between 192.6±2.5 Ma(mineralization host rock)and 189.5±2.6 Ma(overlying lava).Marifil volcanic complex is the host rock for these veins,veinlets and breccias.This particular small deposit has developed low to intermediate sulphidation characteristics,with gangue mineral textures associated with several ore minerals.Electron probe microanalysis determines electrum,silver minerals such as acanthite,and tetrahedrite,related Ag-Cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena and pyrite.Fluid inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%NaCl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 m.This particular character has not been previously recorded for other sectors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions Chon Aike geochronology

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Degradation of nucleic acids and nucleotides in several conditions with perspectives of retrieval: A review

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Advances in Bioscience and Biotechnology 2014年第1期5卷 36-39页

作者： José Martínez Reyes Lenin Ejecatl Medina Orozco Melitón Estrada Jaramillo Iván Vera Romero agustina ortiz soriano Trajectory of Educational Innovation University of the Ciénega of Michoacán State Sahuayo Méxio Trajectory of Energy Engineering University of the Ciénega of Michoacán State Sahuayo Méxio Trajectory of Food Genomics University of the Ciénega of Mi-choacán State Sahuayo Méxio

Deoxyribonucleic acid (DNA) or oligonucleotides, can be modified in several ways as chemical degradation by electrophilic reaction, attack of radicals, hydrolytic deamination or oxidative damage caused by ionizing radiation. This work discussed these degradation mechanisms, determining the effects on these biomolecules. The actual knowledge about DNA damages only permits partial enzymatic repair treatments.

关键词： DNA Chemical Degradation

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Biogas Estimation as a Basis for the Implementation of an Intermunicipal Landfill: Michoacan, Mexico

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Journal of Environmental Protection 2014年第7期5卷 577-582页

作者： Iván Vera-Romero José Martínez Reyes Claudio C. Espíritu-Barragán Melitón Estrada-Jaramillo agustina ortiz-soriano Lenin E. Medina-Orozco Trajectory of Educational Innovation University of the Cienega of Michoacan State Sahuayo Mexico Trajectory of Energy Engineering University of the Cienega of Michoacan State Sahuayo Mexico Trajectory of Food Genomics University of the Cienega of Michoacan State Sahuayo Mexico

Municipal solid waste (MSW) generated in the municipalities of Sahuayo, Jiquilpan and Venustiano Carranza in Michoacan, is deposited in open dumps becoming hot spots for health and the environment. The total population in the three municipalities is 130,497 habitants, with a per capita waste production estimated in 0.718 kg·hab-1·day-1 (34,203 t·yr-1). The aim of this study was to estimate the formation of biogas for power generation from the decomposition of waste. The model used was the mexican model of biogas (version 2.0), assuming a useful life of 21 years of the landfill at a cost of 0.19 USD per kWh, the average CFE rate for municipal public lighting. Four possible scenarios were evaluated: one optimal recovering 68% of the biogas (10,095 tonnes of methane in 20 years), having a savings concept in electricity of 8,015,252 USD;in the second case (optimistic intermediate), it is assumed that it obtains 61% of biogas (9046 tonnes of methane) with benefits in power generation for 7,159,679 USD;the third case (pessimistic intermediate) estimating 48% of biogas recovered, being captured 7118 tonnes of methane with profits of 5,633,846 USD into electrical energy, the latter case (pessimistic), assuming 40% of biogas recovered, transforming 4672 tonnes of methane resultant in an economic benefit of 3,697,324 USD for electricity generation. The results justify the investment of the landfill and it is a measure to mitigate climate change and disease prevention.

关键词： Municipal Street Lighting Alternative Energy Public Health

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Geochemical Prospection of the Chapala Ciénega at Michoacán State

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International Journal of Geosciences 2014年第9期5卷 1007-1011页

作者： José Martínez Reyes Ivan Vera Romero Meliton Estrada Jaramillo agustina ortiz soriano Ignacio Moreno Nava Francisco Gabriel Montes Ayala Francisco García ávalos Ernesto Mendez Ruiz 1University of the Ciénega of Michoacán State Sahuayo México 2Michoacan Society of History Archaeology and Geography A.C. La Palma de Jesús México Michoacan Society of History Archaeology and Geography A.C. La Palma de Jesús México University of the Ciénega of Michoacán State Sahuayo México

The geochemical prospection as a branch of Applied Geochemistry or “Geochemistry of the Landscape” studies the spatial and temporal location of geochemical anomalies in order to locate geological resources of economic value. The Ciénega de Chapala zone in Michoacán is located east of the Citala rift hosting a geological system that leads to regional hydrothermal activity, mainly the Pajacuaran and Ixtlan failures. The regional geothermics include a superficial hydrothermalism consisting of springs and wells of hot water with temperatures between 48°C and 94°C in Ixtlan de los Hervores and mud volcanoes in the water with temperatures between 48°C and 94°C in Ixtlan de los Hervores and mud volcanoes in the Los Negritos. The waters and gases of these hydrothermal manifestations have physicochemical characteristics that indicate the presence of geothermal fluids. To search for possible presence of minerals of economic value, a study of elemental chemical analysis was performed by scanning electron microscopy in samples of rock of the sierra de Pajacuaran, the result of the analysis is clearly abnormal values which may be indicative a geochemical anomaly as well as the possible presence of minerals of economic value in the region. Given the above, the area of the Ciénega de Chapala in Michoacán is a zone where work can be continued both geothermal and mineralogical exploration by conventional techniques or even totally innovative technologies.

关键词： Geochemical Prospection Ciénega Michoacán

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Load dependent microstructural evolution in an as-cast 26%Cr high chromium cast iron during unlubricated sliding

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Friction 2022年第8期10卷 1258-1275页

作者： U.Pranav NAYAK Sebastian SUÁREZ Valentin PESNEL Frank MÜCKLICH María agustina GUITAR Department of Materials Science Saarland UniversitySaarbrücken 66123Germany Materials Engineering Center Saarland Saarbrücken 66123Germany Ecole Européenne d’ingénieurs en Génie des Matériaux Universitéde LorraineNancy 54000France

In the current study,an as-cast 26%Cr high chromium cast iron(HCCI)alloy was subjected to dry-sliding linear wear tests,under different loads.The loads were selected based on analytically computing the critical load(PC)i.e.,the load necessary to induce plastic deformation.The PC was calculated to be 15 N and accordingly,a sub-critical load(5 N)and an over-critical load(20 N)were chosen.The influence of increasing the load during the wear test was investigated in terms of the matrix microstructural behaviour and its ability to support the surrounding carbides.The morphological aspects of the wear tracks,and the deformed matrix microstructure adjacent and underneath the track was analysed by confocal laser scanning microscope(CLSM)and scanning electron microscope(SEM),respectively.No evidence of plastic deformation of the matrix was observed below PC.On the contrary,at loads equal to and higher than PC,the austenitic matrix plastically deformed as evidenced by the presence of slip bands.Electron backscattered diffraction(EBSD)measurements in terms of grain reference orientation deviation,and micro-Vickers hardness of the austenitic matrix indicated a deformation depth of about 40μm at the maximum applied load of 20 N.The active wear mechanisms during sliding were a combination of both adhesive and abrasive wear,although increasing the load shifted the dominant mechanism towards abrasion.This was primarily attributable to the increased propensity for carbide cracking and fracturing,combined with the inability of the hardened austenitic matrix surface and sub-surface to adequately support the broken carbide fragments.Moreover,the shift in the dominant wear mechanism was also reflected in the wear volume and subsequently,the wear rate.

关键词： high chromium cast iron unlubricated sliding plastic deformation wear resistance carbide spallation matrix hardness

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Influence of structural depth of laser-patterned steel surfaces on the solid lubricity of carbon nanoparticle coatings

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Friction 2023年第7期11卷 1276-1291页

作者： Timothy MACLUCAS Lukas DAUT Philipp GRÜTZMACHER Maria agustina GUITAR Volker PRESSER Carsten GACHOT Sebastian SUAREZ Frank MÜCKLICH Chair of Functional Materials Saarland UniversitySaarbrücken 66123Germany Institute for Engineering Design and Product Development TU WienWien 1060Austria INM–Leibniz Institute for New Materials Saarbrücken 66123Germany Department of Materials Science&Engineering Saarland UniversitySaarbrücken 66123Germany Saarene-Saarland Center for Energy Materials and Sustainability Saarbrücken 66123Germany

Carbon nanoparticle coatings on laser-patterned stainless-steel surfaces present a solid lubrication system where the pattern's recessions act as lubricant-retaining reservoirs.This study investigates the influence of the structural depth of line patterns coated with multi-walled carbon nanotubes(CNTs)and carbon onions(COs)on their respective potential to reduce friction and wear.Direct laser interference patterning(DLIP)with a pulse duration of 12 ps is used to create line patterns with three different structural depths at a periodicity of 3.5μm on AISI 304 steel platelets.Subsequently,electrophoretic deposition(EPD)is applied to form homogeneous carbon nanoparticle coatings on the patterned platelets.Tribological ball-on-disc experiments are conducted on the as-described surfaces with an alumina counter body at a load of 100 mN.The results show that the shallower the coated structure,the lower its coefficient of friction(COF),regardless of the particle type.Thereby,with a minimum of just below 0.20,CNTs reach lower COF values than COs over most of the testing period.The resulting wear tracks are characterized by scanning electron microscopy,transmission electron microscopy,and energy-dispersive X-ray spectroscopy.During friction testing,the CNTs remain in contact,and the immediate proximity,whereas the CO coating is largely removed.Regardless of structural depth,no oxidation occurs on CNT-coated surfaces,whereas minor oxidation is detected on CO-coated wear tracks.

关键词： solid lubricant coatings carbon nanotubes carbon onions direct laser interference patterning(DLIP)surface structuring electrophoretic deposition(EPD)

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Impact of chitosan-based nanocarriers on cytoskeleton dynamics:Current status and challenges

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BIOCELL 2022年第4期46卷 885-891页

作者： M.CAROLINA DI SANTO agustina ALAIMO ANA PAULA DOMÍNGUEZ RUBIO OSCAR E.PÉREZ Departamento de Química Biológica Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresBuenos AiresArgentina Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales Consejo Nacional de Investigaciones Científicas y Técnicas(IQUIBICENCONICET)Buenos AiresArgentina

Chitosan-based nanocarriers(CS-NCs)show a promising role in improving drugs and bioactive compounds delivery for therapy.However,the effects exerted by CS-NCs at the cellular level,including their recognition and uptake,have not been fully investigated yet.Many factors,including size,shape,concentration,and surface chemistry of CS-NCs,play an important role in determining the types of intracellular signals triggered.The mechanism of uptake and the involvement of the cytoskeleton during the CS-NCs endocytosis variates among the different cell types as well as further effects observed inside cells.In the present work,we discuss the effects induced by CS-NCs per se on the cytoskeleton,a key component in cell architecture and physiology.The focus of this report is made on tumoral and normal biological models in which CS-NCs could differentially affect the cell cytoskeleton.The recent years reports regarding the impact of CS-NCs on cytoskeleton dynamics and the current techniques for its evaluation are summarized and discussed.Understanding mechanisms underlying cytoskeletal impact after cell exposure to CS-NCs is critical for the design of safest value-added formulations in the biomedical field.Furthermore,this revision points out some interesting aspects of cytoskeletal changes and cell death encompassing anti-tumoral effects.

关键词： Cytoskeletal dynamics Cellular uptake Endocytosis Nanocarriers Chitosan Bioactive compounds

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Nicotinic receptors modulate antitumor therapy response in triple negative breast cancer cells

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World Journal of Clinical Oncology 2022年第6期13卷 505-519页

作者： Alejandro Español Yamila Sanchez agustina Salem Jaqueline Obregon Maria Elena Sales Laboratory of Immunopharmacology and Tumor Biology CEFYBO CONICET University of Buenos AiresBuenos Aires C1121ABGArgentina

BACKGROUND Triple negative breast cancer is more aggressive than other breast cancer subtypes and constitutes a public health problem worldwide since it has high morbidity and mortality due to the lack of defined therapeutic targets.Resistance to chemotherapy complicates the course of patients’treatment.Several authors have highlighted the participation of nicotinic acetylcholine receptors(nAChR)in the modulation of conventional chemotherapy treatment in cancers of the airways.However,in breast cancer,less is known about the effect of nAChR activation by nicotine on chemotherapy treatment in smoking patients.AIM To investigate the effect of nicotine on paclitaxel treatment and the signaling pathways involved in human breast MDA-MB-231 tumor cells.METHODS Cells were treated with paclitaxel alone or in combination with nicotine,administered for one or three 48-h cycles.The effect of the addition of nicotine(at a concentration similar to that found in passive smokers’blood)on the treatment with paclitaxel(at a therapeutic concentration)was determined using the 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.The signaling mediators involved in this effect were determined using selective inhibitors.We also investigated nAChR expression,and ATP“binding cassette”G2 drug transporter(ABCG2)expression and its modulation by the different treatments with Western blot.The effect of the treatments on apoptosis induction was determined by flow cytometry using annexin-V and 7AAD markers.RESULTS Our results confirmed that treatment with paclitaxel reduced MDA-MB-231 cell viability in a concentration-dependent manner and that the presence of nicotine reversed the cytotoxic effect induced by paclitaxel by involving the expression of functionalα7 andα9 nAChRs in these cells.The action of nicotine on paclitaxel treatment was linked to modulation of the protein kinase C,mitogen-activated protein kinase,extracellular signal-regulated kinase,and NF-κB signaling pathways,and to an up-regulation of ABCG2 protein express

关键词： Breast cancer Paclitaxel Nicotinic acetylcholine receptors Drug therapy Signal transduction Drug transporter

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Anticancer drug screening of natural products:In vitro cytotoxicity assays,techniques,and challenges

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Asian Pacific Journal of Tropical Biomedicine 2022年第7期12卷 279-289页

作者： agustina Setiawati Damiana Sapta Candrasari F.D.Erika Setyajati Vincentia Krisnina Prasetyo Dewi Setyaningsih Yustina Sri Hartini Faculty of Pharmacy Sanata Dharma UniversityPainganMaguwoharjoDepokSlemanYogyakarta 55282Indonesia

Natural products include several diverse compounds that have been found to be effective against cancer.Discovering anticancer compounds in nature is a multistep and complex process that requires pre-clinical and clinical studies.Only a few of the available natural products are used to treat cancer since most of them have very high complexity and low bioavailability.Therefore,the process of anticancer drug discovery requires a straightforward and effective method to assess anticancer activity using in vitro assays.This review summarizes various cell-based assays and techniques used to measure cell viability,migration,and apoptosis,focusing in particular on the principles,mechanisms,advantages,and disadvantages of each assay to provide a preliminary platform for cancer drug discovery.

关键词： Drug discovery Cancer Natural products Screening In vitro assay Cytotoxicity Migration Apoptosis

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Epigenetic modulations rendering cell-to-cell variability and phenotypic metastability

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Journal of Genetics and Genomics 2016年第8期43卷 503-511页

作者： Shawal Spencer agustina Gugliotta Natascha Godecke Hansjorg Hauser Dagmar Wirth Model Systems for Infection and Immunity Helmholtz Centre for Infection ResearchBraunschweig 38124Germany Experimental Hematology Hannover Medical SchoolHannover 30625Germany cell culture laboratory faculty of biochemistry and biological sciencesnational university of the littoralSanta Fe 3000Argentina

Tumor cells display phenotypic plasticity and heterogeneity due to genetic and epigenetic variations which limit the predictability of therapeutic interventions. Chromatin modifications can arise stochas- tically but can also be a consequence of environmental influences such as the microenvironment of cancer cells. A better understanding of the impact and dynamics of epigenetic modulation at defined chromosomal sites is required to get access to the underlying mechanisms. We investigated the epige- netic modulations leading to cell-to-cell heterogeneity in a tumor cell line model. To this end, we analyzed expression variance in 80 genetically uniform cell populations having a single-copy reporter randomly integrated in the genorne. Single-cell analysis showed high intraclonal heterogeneity. Epige- netic characterization revealed that expression heterogeneity was accompanied by differential histone marks whereas contribution of DNA methylation could be excluded. Strikingly, some clones revealed a highly dynamic, stochastically altered chromatin state of the transgene cassette which was accompanied with a metastable expression pattern. In contrast, other clones represented a robust chromatin state of the transgene cassette with a stable expression pattern. Together, these results elucidate locus-specific epigenetic modulation in gene expression that contributes to phenotypic heterogeneity of cells and might account for cellular plasticity.

关键词： lntraclonal heterogeneityEpigenetic regulationDNA methylationDifferential histone marksMetastable expression

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