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Degradation of duloxetine: Identification of transformation products by UHpLC-ESI(+)-HRMS/MS,in silico toxicity and wastewater analysis

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Journal of Environmental Sciences 2019年第8期31卷 113-123页

作者： Rodrigo A.Osawa ana p.carvalho Olinda C.Monteiro M.Conceicao Oliveira M.Helena Florêncio Centro de Química e Bioquímica Faculdade de Ciências Universidade de Lisboa Laboratório de FTICR e Espectrometria de Massa Estrutural Faculdade de Ciências Universidade de Lisboa Centro de Química Estrutural Instituto Superior Técnico Universidade de Lisboa

Duloxetine(DUL), an antidepressant drug, has been detected in surface water and wastewater effluents, however, there is little information on the formation of its transformation products(Tps). In this work, hydrolysis, photodegradation(UV irradiation) and chlorination experiments were performed on spiked distillated water, under controlled experimental conditions to simulate abiotic processes that can occur in the environment and wastewater treatment plants(WWTps). Eleven Tps, nine from reaction with UV light and two from chlorine contact, were formed and detected by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry, and nine of them had their chemical structures elucidated upon analyses of their fragmentation patterns in MS/MS spectra. The formation and degradation of the Tps were observed. The parent compound was completely degraded after30 min in photodegradation and after 24 hr in chlorination. Almost all Tps were completely degraded in the experiments. The ecotoxicity and mutagenicity of the Tps were predicted based on several in silico models and it was found that a few of these products presented more ecotoxicity than DUL itself and six Tps showed positive mutagenicity. Finally, wastewater samples were analyzed and DUL and one Tp, possibly formed by chlorination process, were detected in the effluent, which showed that WWTp not only did not remove DUL, but also formed a Tp.

关键词： High resolution mass spectrometry Duloxetine Degradation processes Transformation products Wastewater analysis In silico toxicity

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Hydrocarbons in particulate samples from wildfire events in central portugal in summer 2010

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Journal of Environmental Sciences 2017年第3期29卷 122-131页

作者： ana Vicente ana Calvo ana p.Fernandes teresa Nunes Cristina Monteiro Casimiro pio Célia Alves Centre for Environmental and Marine Studies (CESAM) Department of EnvironmentUniversity of Aveiro Department of physics IMARENABUniversity of León

In summer 2010, twenty eight （14 pM=2.5 samples plus 14 samples pM2.5-10） smoke samples were collected during wildfires that occurred in central portugal. A portable high-volume sampler was used to perform the sampling, on quartz fibre filters of coarse （pM=2.5-10） and fine （pM2.5） smoke samples. The carbonaceous content （elemental and organic carbon） of particulate matter was analysed by a thermal-optical technique. Subsequently, the particulate samples were solvent extracted and fractionated by vacuum flash chromatog- raphy into three different classes of organic compounds （aliphatics, polycyclic aromatic hydrocarbons （pAHs） and carbonyl compounds）. The organic speciation was performed by gas chromatography-mass spectrometry （GC-MS）. Emissions were dominated by the fine particles, which represented around 92% of the pM10. A clear predominance of carbonaceous constituents was observed, with organic to elemental carbon （OC/EC） ratios ranging between 1.69 and 245 in both size fractions. The isoprenoid ketone 6,10,14-trimethyl-2-pentadecanone, a tracer for secondary organic aerosol formation, was one of the dominant constituents in both fine and coarse particles. Retene was the most abundant compound in all samples. Good correlations were obtained between OC and both aliphatic and pAH compounds. pyrogenic processes, thermal release of biogenic com- pounds and secondary processing accounted for 97% of the apportioned pM2.5 levels.

关键词： WildfiresOrganic carbonOrganic compoundsBiomarkersparticulate matterportugal

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Natural Mg silicates with different structures and morphologies: Reaction with K to produce K2MgSiO4 catalyst for biodiesel production

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 46-54页

作者： Fabiane carvalho Ballotin Mayra Nascimento Sara Silveira Vieira Alexandre carvalho Bertoli Ottávio Carmignano ana paula de carvalho Teixeira Rochel Montero Lago Departamento de Química Universidade Federal de Minas GeraisBelo HorizonteBrasil Doutorado Inovação/Mineradora pedras Congonhas Universidade Federal de Minas Gerais31270-901 Belo Horizonte-MGBrazil

In this work, different magnesium silicate mineral samples based on antigorite, lizardite, chrysotile(which have the same general formula Mg3Si2O5(OH)4), and talc(Mg3Si4O10(OH)2) were reacted with KOH to prepare catalysts for biodiesel production. Simple impregnation with 20 wt% K and treatment at 700–900°C led to a solid-state reaction to mainly form the K2MgSiO4 phase in all samples. These results indicate that the K ion can diffuse into the different Mg silicate structures and textures, likely through intercalation in the interlayer space of the different mineral samples followed by dehydroxylation and K2MgSiO4 formation. All the materials showed catalytic activity for the transesterification of soybean oil(1:6 of oil : methanol molar ratio, 5 wt% of catalyst, 60°C). However, the best results were obtained for the antigorite and chrysotile precursors, which are discussed in terms of mineral structure and the more efficient formation of the active phase K2MgSiO4.

关键词： silicate serpentinite lizardite antigorite talc chrysotile biodiesel

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Thermal and Mechanical properties of Thermoplastic Starch and poly(Vinyl Alcohol-Co-Ethylene)Blends

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Journal of Renewable Materials 2019年第3期7卷 245-252页

作者： ana Clara Lancarovici Alves Rafael Grande Antonio José Felix carvalho Department of Materials Engineering Sao Carlos School of EngineeringUniversity of Sao PauloAv.Joao Dagnone110013563-120Sao Carlos-SP-Brazil

The interest in thermoplastic starch(TpS)as a substitute material to replace conventional thermoplastics continues especially due its biodegradability,availability,low cost and because it is obtained from renewable ***,its poor mechanical properties and its high sensitivity to humidity have limited its use in several ***,the copolymer poly(ethylene-co-vinyl alcohol)(EVOH),with two different ethylene contents,27 and 44 mol%were blended with TpS by extrusion in order to overcome these *** obtained blends were characterized by thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),mechanical tensile testing,Scanning Electron Microscopy(SEM)and moisture absorption *** addition of EVOH copolymer did not significantly changed the thermal stability of TpS,however it increased the tensile strength in 65%when compared to *** morphology of the blends did not showed two distinct phases,an indication of miscibility or partial miscibility of the components.A decrease of moisture absorption was obtained by the addition of EVOH and is more pronounced for the EVOH with 44% of ethylene.

关键词： Thermoplastic starch EVOH polymer blends thermal properties of polymers mechanical properties of polymers

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Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

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Journal of Magnesium and Alloys 2024年第4期12卷 1461-1478页

作者： Zohra Benzarti Sandesh Itani JoséDavid Castro Sandra carvalho ana Sofia Ramos University of Coimbra CEMMPREARISEDepartment of Mechanical EngineeringRua Luís Reis Santos3030-788CoimbraPortugal Laboratory of Multifunctional Materials and Applications(LaMMA) Department of PhysicsFaculty of Sciences of SfaxUniversity of SfaxSoukra Road km 3.5B.P.1171Sfax3000Tunisia

Magnesium(Mg)alloys are widely used for temporary bone implants due to their favorable biodegradability,cytocompatibility,hemocompatibility,and close mechanical properties to ***,rapid degradation and inadequate strength limit their *** overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)*** approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising *** leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and *** paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings,denoted Mg-xZr(x=0–5 at.%).Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr *** analysis confirmed the presence of the Mg(00.2)basal plane,shifting towards higher angles(1.15°)with 5 at.%Zr doping due to lattice parameter changes(i.e.,decrease and increase of“c”and“a”lattice parameters,respectively).Mg–Zr coatings exhibited“liquidphilic”behavior,while Young’s modulus retained a steady value around 80 Gpa across all ***,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)Gpa for 5 at.%*** testing in simulated body fluid(SBF)at 37℃ revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.%*** with the 5 at.%Zr coating which exhibited a corrosion rate of 32 mm/year,these coatings displayed lower corrosion rates,ranging from 1 to 12 mm/*** synergistic enhancement in mechanical properties and corrosion resistance,achieved with 2.0–3.4 at.%Zr,suggests potential ability for reducing stress shielding and controlled degradation performance,and consequentl

关键词： Mg-Zr coatings Magnetron sputtering Nanoindentation Corrosion resistance Bone implants

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Fluorescent probes for the detection of reactive oxygen species in human spermatozoa

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Asian Journal of Andrology 2020年第5期22卷 465-471页

作者： Sara Escada-Rebelo Francisca G Mora ana p Sousa teresa Almeida-Santos Artur paiva Joao Ramalho-Santos phD programme in Experimental Biology and Biomedicine CNC-Center for Neuroscience and Cell BiologyUniversity of CoimbraCoimbra 3004-504Portugal Biology of Reproduction and Stem Cell Group CNC-Center for Neuroscience and Cell BiologyUniversity of CoimbraCoimbra 3004-504Portugal IIIUC-Institute for Interdisciplinary Research Casa Costa AlemaoUniversity of CoimbraCoimbra 3030-789Portugal Reproductive Medicine Unit University Hospitals of CoimbraCoimbra 3004-561Portugal Faculty of Medicine University of CoimbraCoimbra 3000-370Portugal Clinical pathology Unit University Hospitals of CoimbraCoimbra 3004-561Portugal Department of Life Sciences University of CoimbraCoimbra 3000-456Portugal

Reactive oxygen species(ROS)production is a by-product of mitochondrial activity and is necessary for the acquisition of the capacitated state,a requirement for functional ***,an increase in oxidative stress,due to an abnormal production of ROS,has been shown to be related to loss of sperm function,highlighting the importance of an accurate detection of sperm ROS,given the specific nature of this *** this work,we tested a variety of commercially available fluorescent probes to detect ROS and reactive nitrogen species(RNS)in human sperm,to define their *** both flow cytometry(FC)and fluorescence microscopy(FM),we confirmed that MitoSOX™Red and dihydroethidium(DHE)detect superoxide anion(as determined using antimycin A as a positive control),while DAF-2A detects reactive nitrogen species(namely,nitric oxide).For the first time,we also report that RedoxSensor™Red CC-1,CellROX®Orange Reagent,and MitopYl seem to be mostly sensitive to hydrogen peroxide,but not ***,mean fluorescence intensity(and not percentage of labeled cells)is the main parameter that can be reproducibly monitored using this type of methodology.

关键词： flow cytometry fluorescent probes human spermatozoa oxidative stress reactive oxygen species

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Thiopurine-methyltransferase variants in inflammatory bowel disease:prevalence and toxicity in Brazilian patients

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World Journal of Gastroenterology 2014年第12期20卷 3327-3334页

作者： ana teresa p.carvalho Barbara C Esberard Renata S B Fróes Davy C M Rapozo ana B Grinman Tatiana A Simo Juliana C V C Santos Antonio José V Carneiro Luis Felipe Ribeiro-pinto Heitor S p de Souza Disciplina de Gastroenterologia e Endoscopia Digestiva Universidade do Estado do Rio de Janeiro programa de Carcinogênese Molecular Instituto Nacional de Cancer Laboratório de Toxicologia e Biologia Molecular Universidade do Estado do Rio de Janeiro Servi?o de Gastroenterologia Departamento de Clínica MédicaUniversidade Federal do Rio de Janeiro

AIM: To analyze the prevalence of thiopurine-methyltransferase (TpMT) genotypes and their association with drug toxicity in inflammatory bowel disease (IBD) patients from southeastern Brazil.

关键词： Inflammatory bowel disease Thiopurine-methyl-transferase Azathioprine Drug toxicity pancreatitis

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The road to sustainable use and waste management of plastics in portugal

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Frontiers of Environmental Science & Engineering 2022年第1期16卷 91-106页

作者： Joana C.prata ana Lpatrício Silva Armando CDuarte teresa Rocha-Santos Centre for Environmental and Marine Studies(CESAM)&Department of Chemistry University of Aveiro3810-193 AveiroPortugal Centre for Environmental and Marine Studies(CESAM)&Department of Biology University of Aveiro3810-193 AveiroPortugal

As a European Union(EU)member,portugal must comply with reductions in plastic *** portugal,the 330 items/100 m of beach litter,comprising up to 3.9 million pieces and of which 88%is plastic,is higher than the EU median(149 items/100 m)and must be reduced to 20 items/100 m(94%).Integrative measures are needed to reduce littering and improve plastics’use and disposal under the circular *** this 414 kt of plastic packaging waste,163 kt were declared plastic packaging,140 kt subjected to recycling,and 94 kt to energy *** current recycling rate of plastic packaging(34%)should be improved to reach EU recycling averages(42%)and goals and to provide widespread benefits,considering revenues of 167€/*** a net importer of waste,portugal could benefit from the valorization of imported *** increased recycling,pyrolysis and gasification could provide short-term alternatives for producing value-added substances from plastic waste,such as hydrogen,consistent with the National plan of Hydrogen and improving ongoing regulations on single-use *** manuscript provides an integrative view of plastics in portugal,from use to disposal,providing specific recommendations under the circular economy.

关键词： Single-use plastics plastic packaging plastic waste Waste management Waste shipment Lightweight plastic bags

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Integrating geochemical(surface waters, stream sediments)and biological(diatoms) approaches to assess AMD environmental impact in a pyritic mining area： Aljustrel(Alentejo, portugal)

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Journal of Environmental Sciences 2016年第4期28卷 215-226页

作者： ana teresa Luís Nuno Duraes SaloméFernandes pinheiro de Almeida Eduardo Ferreira da Silva University of Aveiro Department of GeosciencesGeoBioTec--GeobiosciencesGeotechnologies and Geoengineering Research CenterCampus de Santiago3810-193 AveiroPortugal University of Aveiro Department of BiologyGeoBioTec--GeobiosciencesGeotechnologies and Geoengineering Research CenterCampus de Santiago3810-193 AveiroPortugal Centro de Ciencias do Mar CCMARUniversidade do AlgarveCampus de Gambelas8005-139 FaroPortugal

Aljustrel mines were classified as having high environmental hazard due to their large tailings volume and high metal concentrations in waters and *** assess acid mine drainage impacted systems whose environmental conditions change quickly,the use of biological indicators with short generation time such as diatoms is *** study combined geochemical and diatom data,whose results were highlighted in 3 groups：Group 1,with low p H（1.9–5.1）and high metal/metalloid（Al,As,Cd,Co,Cu,Fe,Mn,Ni,pb,Zn;0.65–1032 mg/L）and SO4（405–39124 mg/L）*** acidophilic species,pinnularia aljustrelica,was perfectly adapted to the adverse conditions;in contrast,teratological forms of Eunotia exigua were found,showing that metal toxicity affected this *** low availability of metals/metalloids in sediments of this group indicates that metals/metalloids of the exchangeable fractions had been solubilized,which in fact enables metal/metalloid diatom uptake and consequently the occurrence of teratologies;Group 2,with sites of near neutral p H（5.0–6.8）and intermediate metal/metalloid（0.002–6 mg/L）and SO4（302–2179 mg/L）concentrations;this enabled the existence of typical species of uncontaminated streams（Brachysira neglectissima,Achnanthidium minutissimum）;Group 3,with samples from unimpacted sites,showing low metal/metalloid（0–0.8 mg/L）and SO4（10–315 mg/L）concentrations,high pH（7.0–8.4）and Cl contents（10–2119 mg/L）and the presence of brackish to marine species（Entomoneis paludosa）.For similar conditions of acidity,differences in diversity,abundance and teratologies of diatoms can be explained by the levels of metals/metalloids.

关键词： Surface waters Stream sediments Diatoms Metals/metalloids AMD Teratologies

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Small and Medium Enterprises （SMEs） and Competitiveness： An Empirical Study

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Management Studies 2014年第2期2卷 88-95页

作者： Luisa carvalho teresa Costa Open University Lisbon Portugal University of Evora Evora Portugal Institute polytechnic of Setubal Setubal Portugal

Globalisation and competitiveness affected the way of enterprises undertake innovation, particularly in the case of Small and Medium Enterprises （SMEs）. According with European Commission （2013） in Europe 99% of the enterprises is SMEs. SMEs all over the world are considered as the lifeblood of the economies. The importance of this research is justified by the predominance of SMEs that represents the majority of enterprises in portugal. SMEs contribute to the creation of jobs, as well as to the competitiveness of the economies, specially, in crisis time. This study has two main objectives; firstly propose a literature review focused on competitiveness of SMEs. Secondly analysis a sample of 23 enterprises identified as leaders of portuguese SMEs in 2012. The data considering a ranking list of the largest 1,000 portuguese SMEs in 2012, published by Exame （2013）. This analysis considers some SMEs features such as, sales, market share, dimension, and sector. Additionally this research presents a SME case included in this database. Through the application of a questionnaire the study provides a complementary micro perspective of the factors that influences enterprises competitiveness. The questionnaire is divided into three parts： part one refers to the characterization of the enterprise; part two assesses the entrepreneurial competitiveness, considering nine questions to assess performance, six questions to assess internal processes and four questions to understand the relations with customers; and part three analyses the diffusion of innovation through three questions. Finally the study provides important clues relevant for the development of public policies that can support the innovation and competitiveness of SMEs. Moreover the discussions highlight some variables approached in literature review considered as pertinent in the case of innovative SME due to their contribution to exports and to economic growth.

关键词： competitiveness diffusion of innovation performance Small and Medium Enterprises (SMEs) Research and Development (R&D)

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