Halitosis and the pH variation with four mouthwashes

Poster apresentado no XXV Congresso da Ordem dos Médicos Dentistas, 10-12 Novembro 2016. Porto, PortugalSob uma licença CC-BY-NC - http://creativecommons.org/licenses/by-nc/4.0/Introduction: It is estimated that the prevalence of halitosis, varies between 2-44% at world population. It is suggested that the oral pH value is an important factor on the oral microbiota composition which has impact in gaseous breath constitution (2).The aim of this study was to compare the effect of four mouthwashes on salivary pH values, over time.N/

A influência da economia digital na banca de retalho

A atividade da banca de retalho enfrenta novos desafios num contexto económico também ele novo, imprevisível e cheio de incertezas. O objetivo desta dissertação é interpretar as implicações que o digital traz no presente e no futuro das instituições financeiras, tendo sido aplicado o método qualitativo, através das técnicas de revisão da literatura e entrevistas a peritos. No decorrer da pesquisa de informação, tornou-se evidente a existência de quatro pilares chave que influenciam de forma decisiva o novo paradigma de atuação no mercado dos serviços financeiros, são eles: A tecnologia; é um elemento cada vez mais presente e indispensável em qualquer atividade económica; Os novos clientes, as novas gerações obrigam a atuar de forma diferente quando se pensa em lançar produtos ou conquistar clientes; A redução de custos, é uma área em que as empresas têm apostado fortemente, para se defenderem da concorrência, serem mais eficientes, mitigarem a redução de margem financeira (tendo em conta o contexto de taxas de juro muito baixas), e porque em alguns casos, vêm nessa redução a chave para a conquista de mercados à escala global; Os novos concorrentes, isto é, empresas embora não financeiras, têm suportes tecnológicos, know-how e presença em várias geografias e indústrias que lhes confere capacidade de ofertas diferenciadoras e com mais valor, comparativamente aos tradicionais operadores no mercado financeiro. Em conclusão, podemos afirmar que é crítico incrementar o digital na banca, porque se tornou num elemento essencial ao sucesso das organizações e acompanha as alterações em curso na sociedade e na economia. Os bancos estão num processo de mudança de paradigma, de um modelo de negócio baseado no relacionamento comercial cara-a-cara, para uma relação mais tecnológica e baseada na mobilidade. Contudo é necessário assegurar a resposta mais adequada a cada segmento de clientes.The retail banking activity faces new challenges in a new economic context, unpredictable and full of uncertainties. The aim of this work is examine the digital implications in the present and future of financial institutions. The applied method was qualitative, through literature review techniques and interviews with experts. During the research, we were led to consider four key pillars that influence decisively the new paradigm in the financial services market, they are: Technology; it’s an indispensable element in any economic industry; New customers, new generations requires to act differently when we think about launching products or attract customers; The cost reduction, this is an area where companies have made big efforts to defend themselves from the competition, be more efficient, mitigate the reduction in net interest income (seeing very low interest rate environment), and because, in some cases, it’s the key to conquer global markets; New competitors, companies though non-financial, have technological support, know-how and presence across all geographies and industries, which gives them the ability to offer a better proposal and more value, compared to traditional players in the financial market. In conclusion, we can say that it is critical to increase the digital banking, because it has become an essential element to the success of organizations, and follow changes in society and the economy. Banks are in paradigm shift of the business model based on face-to-face relationship, to a more technological relationship, based on mobility. However, it is necessary to ensure the most appropriate response to each customer segment

A influência do firm-generated content na decisão de compra do consumidor

Mestrado em Ciências EmpresariaisA Web 2.0 trouxe o advento das redes sociais e, com elas, novas ferramentas para as marcas utilizarem de forma a persuadir atuais ou potenciais clientes a comprar os seus produtos. O Firm-Generated Content (FGC) é a forma como as empresas utilizam os vários tipos de conteúdo, completamente controlado por elas, de apresentar aos consumidores conteúdo informativo, comentável e partilhável. As empresas têm apostado cada vez mais neste tipo de conteúdos, em conjunto com o User-Generated Content, de forma a melhorar o seu posicionamento no universo online. Este estudo quantitativo tem como objetivo perceber se o FGC influencia a decisão de compra através do Capital de Marca e do Brand Attitude e se a Aptidão Tecnológica tem influência a decisão de compra. Para averiguar estas hipóteses, foi desenvolvido um modelo concetual composto por cinco construtos: FGC, Capital de Marca, Brand Attitude, Decisão de Compra e Aptidão Tecnológica. O modelo foi baseado em 2 estudos recentes e num questionário, do qual resultaram 144 respostas válidas. Para avaliar os resultados, foi usado o método PLS-SEM e, após a devida análise dos resultados obtidos, foi averiguado que o FGC não tem influência no Brand Attitude nem no Capital de Marca, logo não influencia a decisão de compra dos consumidores, mas a Aptidão Tecnológica influencia.Web 2.0 brought the advent of social media and, with it, new tools that brands can use to persuade their current and potential customers to buy their products. Firm-Generated Content (FGC) can be described as the way brands make use of the various types of content at their ~disposal, that is completely controlled by them, in order to show consumers sharable, informative and comment-worthy content. Brands have been betting more and more on this type of content, along with User-Generated Content, in order to improve the positioning in the online universe. This quantitative study has the objective of understanding if FGC influences the ~Portuguese market buying decisions, through a brand’s Brand Equity and Brand Attitude and if tech-savviness has any influence on consumers’ buying decisions. To investigate this hypothesis, a conceptual model was developed, which was composed of 5 constructs: FGC, Brand Equity, Brand Attitude, Buying Decisions and Tech Savviness. This model was based on 2 recent studies and on a survey that was answered by 144 valid respondents. After analyzing the results, the verdict was that the FGC has no influence on Brand Attitude or on Brand Equity, therefore determining that there’s no influence on consumers’ buying decisions, but Tech Savviness does indeed influence these decisions.info:eu-repo/semantics/publishedVersio

Diffusion coefficients of perfluorinated n-alcohols in water and heavy water: experiment and computer simulation

Fluorinated surfactants find nowadays many industrial applications due to their enhanced ability to lower surface tension in aqueous solutions [1]. As a result of their extensive use, emissions of fluorinated surfactants became frequent and, because of their persistent character, have been increasingly found in the environment [2]. Both the development of theoretical models to study the environmental fate of those pollutants and the design of unit operations (e.g. adsorption) used for their removal require the knowledge of some key properties such as the diffusion coefficients in water. n-alcohols with perfluorinated carbon chains can be regarded as the most simple fluorinated surfactants, being suitable to be used as model substances that can make easier the molecular interpretation and the theoretical treatment of fluorinated surfactants in a systematic way. On the other hand, the smallest perfluorinated n-alcohols find applications in many fields, such as the pharmaceutical industry, polymer production and refrigerant technology as components of working fluids. We have recently reported intra-diffusion coefficients of 2,2,2-trifluoroethanol in water for dilute solutions as a function of composition and temperature, obtained both experimentally (NMR spin-echo) and by computer simulation (molecular dynamics) [3]. The results obtained by molecular dynamics closely reproduce the experimental ones, which has encouraged us to attempt predicting the dynamic properties of aqueous solutions of the higher fluorinated alcohols and other fluorinated surfactants. In this work, the intra-diffusion coefficients of 2,2,3,3,3-pentafluoropropan-1-ol, 2,2,3,3,4,4,4-heptafluorobutan-1-ol and 2,2,3,3,4,4,5,5,5-nonafluoropentan-1-ol in water and heavy water were measured experimentally by NMR spin-echo technique and compared with results obtained from computer simulation (molecular dynamics). The comparison that can be done between experimental and simulation results is used to test the theoretical models for this chemical family of substances and enriches the molecular interpretation of the results, which can be useful to anticipate trends for more complex fluorinated surfactants. [1] Buck, R. C.; Franklin, J.; Berger, U.; Conder, J. M.; Cousins, I. T.; de Voogt, P.; Jensen, A. A.; Kannan, K.; Mabury, S. A.; van Leeuwen, S., Integr. Environ. Assess. Manage 2011, 7, 513−541 [2] D’Hollander, W.; de Voogt, P.; De Coen, W.; Bervoets, L., Rev. Environ. Contam. Toxicol. 2010, 208, 179–215 [3] Pereira, L. A. M.; Martins, L. F. G.; Ascenso, J. R.; Morgado, P.; Prates Ramalho, J. P.; Filipe, E. J. M., submitted to publicatio

Novel Antiretroviral Therapeutic Strategies for HIV.

When the first cases of HIV infection appeared in the 1980s, AIDS was a deadly disease without any therapeutic alternatives. Currently, there is still no cure for most cases mainly due to the multiple tissues that act as a reservoir for this virus besides the high viral mutagenesis that leads to an antiretroviral drug resistance. Throughout the years, multiple drugs with specific mechanisms of action on distinct targets have been approved. In this review, the most recent phase III clinical studies and other research therapies as advanced antiretroviral nanodelivery systems will be here discussed. Although the combined antiretroviral therapy is effective in reducing viral loading to undetectable levels, it also presents some disadvantages, such as usual side effects, high frequency of administration, and the possibility of drug resistance. Therefore, several new drugs, delivery systems, and vaccines have been tested in pre-clinical and clinical trials. Regarding drug delivery, an attempt to change the route of administration of some conventional antiretrovirals has proven to be successful and surpassed some issues related to patient compliance. Nanotechnology has brought a new approach to overcoming certain obstacles of formulation design including drug solubility and biodistribution. Overall, the encapsulation of antiretroviral drugs into nanosystems has shown improved drug release and pharmacokinetic profile.This work was supported with Gilead GÉNESE Ref. PGG/006/2016.info:eu-repo/semantics/publishedVersio

Fluorinated surfactants in solution: Diffusion coefficients of fluorinated alcohols in water

Intra-diffusion coefficients of three fluorinated alcohols, 2,2,3,3,3-pentafluoropropan-1-ol (PFP), 2,2,3,3,4,4,4-heptafluorobutan-1-ol (HFB) and 2,2,3,3,4,4,5,5,5-nonafluoropentan-1-ol (NFP) in water have been measured by the PFG–NMR spin-echo technique as a function of temperature and composition, focusing on the alcohol dilute region. For comparison, intra-diffusion coefficients of 2,2,2- trifluoroethanol (TFE) and HFB have also been measured in heavy water using the same method and conditions. As far as we know, these are the first experimental measurements of this property for these binary systems. Intra-diffusion coefficients for NFP in water and for TFE and HFB in heavy water have also been obtained by molecular dynamics simulation, complementing those for TFE, PFP and HFB reported in a previous work. The agreement between experimental and simulated results for PFP, HFB and NFP in water is reasonable, although presenting higher deviations than for the TFE/water system. From the dependence of the intra-diffusion coefficients on temperature, diffusion activation energies were estimated for all the solutes in water and heavy water

On the mobility of dialkyl adipates by PFGSE NMR, computer simulations and other property measurement methods

Encontro realizado em Alacalá de Henares (Madrid), de 22 a 25 de Setembro de 2014Dialkyl adipates are a class of esters materials used as components of lubricants and plasticizers. Diffusion of plasticizers in polymers is a complex process that is difficult to study [1]. As a contribution to understand this phenomenon, the self-diffusion coefficients of five dialkyl adipates (dimethyl, diethyl, dipropyl, dibuthyl and bis(2-ethylhexyl)) were measured by the PFGSTE method in the temperature range 20 to 60ºC. It was shown that these compounds follow the Stokes-Einstein equation [2]. In effect, the self-diffusion coefficients change linearly with T.η-1(η is the viscosity). The dependence of the activation energies for self-diffusion is discussed in terms of size and branching of the alkyl chains of the adipates. Molecular dynamics (MD) simulations were done for these sytems in order to predict the diffusion coefficients as a function of temperature [3]. Acknolwedgements: This work was supported by the Strategic Projects PEst-OE/QUI/UI0100/2011 and PEst-OE/QUI/ UI0100/2013, both funded by Fundação para a Ciência e a Tecnologia (FCT, Portugal). We thank also FCT for funding the NMR facility through Project RECI/QEQ-QIN/0189/2012. References: [1] Rahman M.; Brazel C. S., Prog. Polym. Sci. 2004, 29, 1223–1248. [2] Price W.S, NMR Studies of Translation Motion, Cambridge University Press, Cambridge, 2009. [3] Pereira, L. A. M.; Martins, L. F. G.; Ascenso, J. R; Morgado, P.; Ramalho, J. P. P.; Filipe, E. J. M., J. Chem. Eng. Data 2014, accepted for publication

Diffusion Coefficients of Fluorinated Surfactants in Water:

Intradiffusion coefficients of 2,2,2-trifluoroethanol in water have been measured by the pulsed field gradient (PFG)-NMR spin−echo technique as a function of temperature and composition on the dilute alcohol region. The measurements extend the range of compositions already studied in the literature and, for the first time, include the study of the temperature dependence. At the same time, intradiffusion coefficients of 2,2,2-trifluoroethanol, 2,2,3,3,3-pentafluoropropan-1-ol, and 2,2,3,3,4,4,4-heptafluorobutan-1-ol in water were obtained by computer simulation (molecular dynamics) as a function of composition and temperature. The intradiffusion coefficients of 2,2,2-trifluoroethanol in water obtained by simulation agree with the experimental results, while those of 2,2,3,3,3- pentafluoropropan-1-ol and 2,2,3,3,4,4,4-heptafluorobutan-1-ol are the first estimation of this property for those systems. The molecular dynamics simulations were also used to calculate the intradiffusion coefficients of perfluorooctanesulfonic acid and perfluorooctanoic acid in water at infinite dilution as a function of temperature, which are very difficult to obtain experimentally because of the very low solubility of these substances. From the dependence of the intradiffusion coefficients on temperature, diffusion activation energies were estimated for all the solutes in water

Resolving subunit degeneracy with nonsymmetric pseudocontact shifts

Protein Science (2002), 11:2464–2470Desulfovibrio gigas desulforedoxin (Dx) consists of two identical peptides, each containing one [Fe-4S]center per monomer. Variants with different iron and zinc metal compositions arise when desulforedoxin is produced recombinantly from Escherichia coli. The three forms of the protein, the two homodimers [Fe(III)/Fe(III)]Dx and [Zn(II)/Zn(II)]Dx, and the heterodimer [Fe(III)/Zn(II)]Dx, can be separated by ion exchange chromatography on the basis of their charge differences. Once separated, the desulforedoxins containing iron can be reduced with added dithionite. For NMR studies, different protein samples were prepared labeled with 15N or 15N + 13C. Spectral assignments were determined for [Fe(II)/Fe(II)]Dx and [Fe(II)/Zn(II)]Dx from 3D 15N TOCSY-HSQC and NOESY-HSQC data, and compared with those reported previously for [Zn(II)/Zn(II)]Dx. Assignments for the 13C shifts were obtained from an HNCA experiment. Comparison of 1H–15N HSQC spectra of [Zn(II)/Zn(II)]Dx, [Fe(II)/Fe(II)]Dx and [Fe(II)/Zn(II)]Dx revealed that the pseudocontact shifts in [Fe(II)/Zn(II)]Dx can be decomposed into inter- and intramonomer components, which, when summed, accurately predict the observed pseudocontact shifts observed for [Fe(II)/Fe(II)]Dx. The degree of linearity observed in the pseudocontact shifts for residues 8.5 Å from the metal center indicates that the replacement of Fe(II) by Zn(II) produces little or no change in the structure of Dx. The results suggest a general strategy for the analysis of NMR spectra of homo-oligomeric proteins in which a paramagnetic center introduced into a single subunit is used to break the magnetic symmetry and make it possible to obtain distance constraints (both pseudocontact and NOE) between subunits