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Simultaneous Determination of Ten Endocrine Hormone Disrupters in Water Using SPE/LC-(ESI)MS-MS

Journal of Water Resource and Protection 2010年第9期2卷 818-829页

作者： Marta Henriques Vitor Vale Cardoso Alexandre Mourao Rodrigues elisabete ferreira Maria Joao Benoliel Cristina M.M.Almeida Faculty of Pharmacy Laboratory of HidrologyLisbonPortugal EPAL(Empresa Portuguesa dasÁguas Livres S.A.)Laboratorio Central da EPALLisbonPortugal iMed(The Institute for Medicines and Pharmaceutical Sciences) Faculty of PharmacyLisbonPortugal

The aim of this study was developed and validated an analytical method based on liquid chromatography and tandem mass spectrometry after solid phase extraction to monitorizing ten endocrine hormone disrupters in Lisbon drinking water system. Natural and synthetic hormones (17-β-estradiol, ethinylestradiol, estriol, estrone, progesterone, mestranol and diethylstilbestrol) and some industrial products (4-n-nonylphenol, 4-tert-octylphenol and bisphenol A) were studied. Mass spectrometer detection parameters were optimized, such as the best conditions for the precursor ion formation, namely cone voltage, when applying negative and positive electrospray ionization, and also collision energy for MRM1 and MRM2 transitions. The best conditions of the solid phase extraction (SPE) using Waters Oasis HLB (6 mL, 200 mg) and Isolute C18 (EC) (6 ml, 1000 mg) were also optimized. The method was validated through the application of several statistical tests and the uncertainty estimation of the analytical assay. This method showed a very good linear range for all the studied analytes with determination coefficients (r2) between 0.9962 and 0.9999 and coefficients of variation lower than 4%. There were no significant differences between recoveries obtained with the studied matrices, like groundwater, surface water and water for human consumption. In these matrices, the recovery values varied between 32 and 95%. The limits of method detection were between 0.28 and 22 ng/L. The validated method was applied for the analysis of water samples from the EPAL (Empresa Portuguesa das águas Livres, S.A.) water supply system including tap water, spring water, groundwater, and river water. Some target compounds (bisphenol A, progesterone, 4-tert-octylphenol, and 4-n-nonylphenol) were found in trace amounts in analysed waters.

关键词： Water Analysis Endocrine Disruptors Tandem Mass Spectrometry Solid-phase Extraction Uncertainty Evaluation

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Literature review of accessibility measures and models used in land use and transportation planning in last 5 years

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Journal of Geographical Sciences 2022年第3期32卷 560-584页

作者： Aviral MARWAL elisabete SILVA Department of Land Economy University of CambridgeCambridgeUnited Kingdom

Since its inception accessibility has undergone various changes in the way it is defined,measured,and *** paper reviews the recent advancements made in the accessibility measures along with the models used in different applications of accessibility related to land use and *** measures of accessibility are grouped under infrastructure-based,location-based,and person-based *** paper finds that although the person-based measures are statistically robust and theoretically sound,they are less preferred than the location-based measure in the accessibility *** review finds recent development such as web based mapping and use of location based data;image mapping through convolutional neural networks;and activity-time constraints modeling in the measures of ***,the paper reviews literature from the last five years that have used accessibility to study travel mode choices and household location choices and finds the use of three types of modeling framework-Statistical,Neural Network,and Agent Based *** on the literature review,this paper suggests the inclusion of environmental sustainability and gender equity in the accessibility measurement framework and a shift towards model synthesis to enhance the model accuracy and to reduce the present complexities in model building.

关键词： accessibility travel behavior household location choices agent-based modeling artificial neural network

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A PREDICTOR MODIFICATION TO THE EBDF METHOD FOR STIFF SYSTEMS

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Journal of Computational Mathematics 2011年第2期29卷 199-214页

作者： elisabete Alberdi Juan Jose Anza Lea Artibai Ikastetxea Xemein Avenue 19 48270 Markina-Xemein (Vizcaya) Spain Department of Applied Mathematics ETS de Ingenieria de Bilbao Universidad del Pais Vasco Alameda de Urquijo s/n 48013 Bilbao Spain

In this paper we modify the EBDF method using the NDFs as predictors instead of BDFs. This modification, that we call ENDF, implies the local truncation error being smaller than in the EBDF method without losing too much stability. We will also introduce two more changes, called ENBDF and EBNDF methods. In the first one, the NDF method is used as the first predictor and the BDF as the second predictor. In the EBNDF, the BDF is the first predictor and the NDF is the second one. In both modifications the local truncation error is smaller than in the EBDF. Moreover, the EBNDF method has a larger stability region than the EBDF.

关键词： Backward differentiation formula (BDF) EBDF Predictor Stability Stiff Systems.

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THE INTEGRATION OF STIFF SYSTEMS OF ODEs USING NDFs AND MEBDFs

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Journal of Computational Mathematics 2013年第2期31卷 175-189页

作者： elisabete Alberdi Celaya Juan Jose Anza Department of Applied Mathematics EUIT de Minas y Obras P(tblicas Universidad del Pals Vasco UPV/EHU Colina de Beurko s/n 48902 Barakaldo Spain Department of Applied Mathematics ETS de Ingenieria de Bilbao Universidad del Pals Vasco UPV/EHU Alameda de Urquijo s/n 48013 Bilbao Spain

In this paper we modify the MEBDF method using the NDFs as predictors instead of the BDFs. We have done it in three different ways： changing both predictors of the MEBDF, changing only the first predictor and changing only the second one. We have called the new methods MENDF, MENBDF and MEBNDF respectively. The new methods are A-stable up to order 4 and the stability properties of the new methods are better than the MEBDF method.

关键词： BDF NDF MEBDF Stiff ODEs Stability.

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Optical clearing mechanisms characterization in muscle

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Journal of Innovative Optical Health Sciences 2016年第5期9卷 82-100页

作者： Luís Oliveira M.Inês Carvalho elisabete Nogueira Valery V.Tuchin Physics Department–Polytechnic Institute of Porto School of Engineering Rua Dr.Antonio Bernardino de Almeida 4314200-072 PortoPortugal FEUP–University of Porto Rua Dr.Roberto Frias 4200-465 PortoPortugal CIETI–Centre of Innovation in Engineering and Industrial Technology ISEP Rua Dr.Antonio Bernardino de Almeida4314200-072 PortoPortugal DEEC/FEUP and INESC TEC University of Porto Rua Dr.Roberto Frias 4200-465 PortoPortugal Research-Education Institute of Optics and Biophotonics Saratov National Research State University 83 Astrakhanskaya street Saratov 410012Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precision Mechanics and Control RAS 24 Rabochaya street Saratov 410028Russia Interdisciplinary Laboratory of Biophotonics Tomsk National Research State University 36 Lenin's avenue Tomsk 634050Russia

Optical immersion clearing is a technique that has been widely studied for more than two decades and that is used to originate a temporary transparency effect in biological *** applied in cooperation with clinical methods it provides optimization of diagnosis and treatment *** technique turns biological tissues more transparent through two main mechanisms-tissue dehydration and refractive index(RI)matching between tissue *** matching is obtained by partial replacement of interstit ial water by a biocompat ible agent that presents higher RI and it can be completely rever sible by natural rehydration in vrivo or by assisted rehydration in ex vivo *** data to characterize and discriminate between the two mechanisms and to find new ones are *** a simple method,based on collimated transmittance and thickness measurements made from muscle samples under treatment,we have estimated the diffusion properties of glucose,ethylene glycol(EG)and water that were used to perform such char acterization and *** these properties with data from literature that characterize their diffusion in water we have observed that musde cell membrane permeability limits agent and water diffusion in the *** same experi-mental data has allowed to calculate the optical dearing(OC)eficiency and make an inter-pretation of the internal changes that occurred in muscle during the *** same methodology can now be used to perform similar studies with other agents and in other tissues in order to solve engineering problems at design of inexpensive and robust technologies for a *** improvement of optical tomogr aphic techmiques with better contrast and in depth imaging.

关键词： Collimated transmittance agent diffusivity tissue dehydration thickness variation refractive index matching glucose ethylene glycol

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Mapping of quantitative trait loci using the skew-normal distribution

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第11期8卷 792-801页

作者： FERNANDES elisabete PACHECO António PENHA-GONALVES Carlos Centre for Mathematics and Its Applications IST-Technical University of Lisbon1049-001 LisboaPortugal Department of Statistics and Operational ResearchFaculty of SciencesUniversity of Lisbon1749-016 LisboaPortugal Gulbenkian Institute of ScienceP-2781-901 OeirasPortugal Department of Mathematics and Centre for Mathematics and Its Applications IST-Technical University of Lisbon1049-001 LisboaPortugal Gulbenkian Institute of Science P-2781-901 OeirasPortugal

In standard interval mapping (IM) of quantitative trait loci (QTL), the QTL effect is described by a normal mixture model. When this assumption of normality is violated, the most commonly adopted strategy is to use the previous model after data transformation. However, an appropriate transformation may not exist or may be difficult to find. Also this approach can raise interpretation issues. An interesting alternative is to consider a skew-normal mixture model in standard IM, and the resulting method is here denoted as skew-normal IM. This flexible model that includes the usual symmetric normal distribution as a special case is important, allowing continuous variation from normality to non-normality. In this paper we briefly introduce the main peculiarities of the skew-normal distribution. The maximum likelihood estimates of parameters of the skew-normal distribution are obtained by the expectation-maximization (EM) algorithm. The proposed model is illustrated with real data from an intercross experiment that shows a significant departure from the normality assumption. The performance of the skew-normal IM is assessed via stochastic simulation. The results indicate that the skew-normal IM has higher power for QTL detection and better precision of QTL location as compared to standard IM and nonparametric IM.

关键词： Interval mapping (IM) Quantitative trait loci (QTL) Skew-normal distribution Expectation-maximization (EM)algorithm

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Only Spondylodiscitis? A Clinical Case of Multiple Septic Embolization

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Case Reports in Clinical Medicine 2016年第10期5卷 353-357页

作者： Rita Aguiar Manuel ferreira Gomes elisabete Bento Guerreiro Tiago Marques Carla Santos Department of Immunoallergology Hospital de Santa Maria Centro Hospitalar Lisboa Norte Lisbon Portugal Department of Internal Medicine Hospital de Santa Maria Centro Hospitalar Lisboa Norte Lisbon Portugal Department of Infectious Diseases Hospital de Santa Maria Centro Hospitalar Lisboa Norte Lisbon Portugal

Background: Spondylodiscitis and spinal epidural abscesses are rare pathologic entities, but increasing in incidence. Group G beta hemolytic Streptococcus has been recently described associated with human infections. They often present clinically in a non-specific fashion, a fact which can lead to diagnostic delay, with serious consequences for the patient. Case Report: An 80-year-old man was admitted to the hospital with complaints of fever for three days, dysuria, hematuria, and back pain. Both septic embolizations and spondylodiscitis due to Group G beta hemolytic Streptococcus were detected. The patient was successfully treated with intravenous penicillin G for eight weeks, followed by oral amoxicillin for five months. Discussion: In all patients with spondylodiscitis, infective endocarditis should be considered, particularly in patients with heart valve disease history, since spondylodiscitis may be the presenting sign of an infective endocarditis. A high level of suspicion is therefore necessary in order correctly diagnose such entities as quickly as possible. The present case illustrates the pathogenic potential of group G streptococci in spondylodiscitis and native valve endocarditis.

关键词： Spondylodiscitis Group G Beta Hemolytic Streptococcus Epidural Abscess Embolization

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OPTICAL MEA SUREMENTS OF RAT MUSCLE SAMPLES UND ER TREATMENT WITH ETHYLENE GLYCOL AND GLUCOSE

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Journal of Innovative Optical Health Sciences 2013年第2期6卷 36-50页

作者： LUÍS OLIVEIRA MARIAINÊS CARVALHO elisabete NOGUEIRA VALERYV.TUCHIN Physics Department-Polytechnic of Porto School of Engineering Rua Dr.Antònio Bernardino de Almeida4314200-072 PortoPortugal University of Porto Rua Dr.Roberto Frias 4200-465 Porto Portugal CIETI-Centre of Innovationin Engineering and Industrial Technology ISEPRua Dr.Antònio Bernardino de Almeida4314200-072 PortoPortugal DEEC/FEUP and INESC TEC University of Porto Rua Dr.Roberto Frias4200-465 PortoPortugal Research-Educational Institute of Optics and Biophotonics Saratov State University 83 Astrakhanskaya Str.Saratov 410012Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precise Mechanics and Control RASSaratov 410028Russia Optoelectronics and Measurement Techniques Laboratory P.O.Box 4500 University of OuluFIN-90014OuluFinland

With the objective to study the variation of optical properties of rat muscle during optical clearing,we have performed a set of optical measurements from that kind of *** performed were total tr ansmittance,ollimated transmit tance,specular reflec-tance and total *** set of measurements is suficient to determine diffuse reflectance and absorbance of the sample,also necessary to est imate the optical *** the per formed measurements and calculated quantities will be used later in inverse Monte Carlo(IMC)simu-lations to determine the evolution of the optical properties of muscle during treatments with ethylene glycol and *** results obt ained with the measurements already provide some information about the optical c learing treatments applied to the muscle and translate the mechanisms of turning the tissue more transparent and sequence of regimes of optical clearing.

关键词： Tissue optical clearing optical transmittance optical reflectance optical absorbance agent difusivity

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Tracheobronchial Polyflex stents for the management of benign refractory hypopharyngeal strictures

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World Journal of Gastroenterology 2012年第6期18卷 551-556页

作者： Rui Almeida Silva Nuno Mesquita Pedro Pimentel Nunes elisabete Cardoso Ricardo Marcos Pinto Luís Moreira Dias Department of Gastroenterology Instituto Português de Oncologia do Porto Francisco GentilR.Doutor António Bernardino de Almeida 4200-072PortoPortugal Department of Gastroenterology Centro Hospitalar do PortoLargo Prof.Abel Salazar 4099-001PortoPortugal

AIM:To describe a modified technique for placement of a tracheobronchial self-expanding plastic stent(SEPS) in patients with benign refractory hypopharyngeal strictures in order to improve dysphagia and allow stricture ***:A case series of four consecutive patients with complex hypopharyngeal strictures after combinedtherapy for laryngeal cancer,previously submitted to multiple sessions of dilation without lasting improvement,is *** patients underwent placement of a small diameter and unflared tracheobronchial *** outcome measurements were improvement of dysphagia and avoiding of repeated ***:The modified introducer system allowed an easy and technically successful deployment of the tracheobronchial Polyflex stent through the *** four patients developed complications related to stent *** patients had stent migration(one proximal and one distal),two patients developed phanryngocutaneous fistulas and all patients with stents in situ for more than 8 wk had hyperplastic tissue growth at the upper end of the *** recurrence was observed at 4 wk follow-up after stent removal in all patients CONCLUSION:Although technically feasible,placement of a tracheobronchial SEPS is associated with a high risk of *** diameter stents must be kept in place for longer than 3 mo to allow adequate time for stricture remodeling.

关键词： Larynx neoplasms Hypopharynx Strictures Dilation Stents

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Family Firms and the Market Reaction to Dividend News

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Journal of Modern Accounting and Auditing 2013年第4期9卷 527-541页

作者： elisabete F Simoes Vieira Aveiro University Aveiro Portugal

This paper provides an analysis of the market reaction to dividend change announcements for publicly-traded, family-controlled firms. Family firms have a significantly lower proportion of independent directors than non-family firms, which is consistent with the idea that family members dominate the board of directors and that family shareholders are common in publicly-traded firms. The author analyzed 390 dividend change announcements in Portugal over the period from 1991 to 2010 using a panel data approach. The results show no evidence of a significant market reaction to dividend change announcements, providing no evidence in support of the dividend-signaling hypothesis in the context of family firms. This conclusion agrees with previous studies in which there was no distinction between family and non-family firms. Empirical results show that family firms engage in lower payouts than their non-family counterparts, giving some supports to the expropriation hypothesis. This finding may indicate that families expropriate the wealth of shareholders through lower dividends. This result is also consistent with the clientele theory of dividends.

关键词： family firms cash dividends signaling hypothesis market reaction

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