204 research outputs found
Sustainability and the digital age: exploring sustainable production and consumption behaviors
The digital age had a profound impact on communications and businesses,exacerbating the worldwide rate of consumption and production that depletes Earth’s natural resources. This paper explores how the digital age relates to businesses' and consumers' sustainable practices. Results from an online questionnaire and a company interview, support that companies have adapted to the digital world and to the increasingly demanding and conscientious consumers. Society is making progress, nevertheless, although individuals are more aware of their consumption's negative impact on the environment and are changing the way they dispose of and use products, their purchase habits are still mainly unaltered
Unveiling the antifungal resistance mechanisms of the emergent fungal pathogen Candida parapsilosis
Purification and biochemical/molecular characterisation of antimicrobial peptides produced by Saccharomyces cerevisiae and evaluation of their mode of action
Doutoramento em Engenharia Alimentar / Instituto Superior de AgronomiaThe antagonistic effect exerted by Saccharomyces cerevisiae against other microbial species
during wine fermentations was recently ascribed to its capacity to secrete antimicrobial peptides
(AMPs). The main goal of the present work was to purify, identify and characterize those
AMPs. Firstly, the AMPs were purified by means of chromatographic techniques (sizeexclusion
and ion-exchange) and then characterized regarding their amino acid sequence,
codifying genes and antimicrobial/biochemical properties. Analysis of the purified AMPs by
mass spectrometry revealed that the natural biocide is mainly composed by two peptides
(AMP1 and AMP2/3) derived from the isoenzymes of the glycolytic protein glyceraldehyde 3-
phosphate dehydrogenase (GAPDH). The spectrum of action of the naturally-excreted AMPs,
which we named saccharomycin, is wide and includes several wine-related non-Saccharomyces
yeasts, such as Hanseniaspora guilliermondii, Torulaspora delbrueckii, Kluyveromyces
marxianus, Lachancea thermotolerans and Dekkera bruxellensis, as well as bacteria such as
Oenococcus oeni. The antimicrobial effect of saccharomycin is significantly higher than that of
synthetic analogues (AMP1 and AMP2/3) and depends on their complementary action and
relative proportion. The mode of action of the AMPs was evaluated against sensitive yeast cells.
The AMPs induce cell membrane permeabilization, loss of pH homeostasis and
increase/decrease of H+-influx/-efflux. They also induce cell molecular markers typical of death
by apoptosis in H. guilliermondii. Our work also revealed the accumulation of these GAPDHderived
peptides on the surface of stationary-grown (48 h) cells of S. cerevisiae, which induce
death of non-Saccharomyces yeasts (H. guilliermondii and L. thermotolerans) by direct cell-cell
contact. Finally, S. cerevisiae strains over-expressing these AMPs prevented growth of D.
bruxellensis in co-fermentations, decreasing the levels of sulphur dioxide needed to control
wine spoilage. Thus, the potential of these AMPs to be used as biopreservative in wine seems
promisingN/
Is digital influencers’ content more effective than your brands’ in creating online brand related content?: The impact of perceptions regarding digital influencers as source of brand content on consumers’ purchase intention of beauty brands
The rise of social media content generated by consumers about beauty products/services has
caught the attention of brands from that segment, where some consumers ascended to digital
influencers - revealing to be effective in influencing purchase decisions. Considering this,
beauty brands started to increasingly resource to influencers with that purpose. The question of
whether this content creation by influencers is more effective in generating brand outputs than
content created by the brand itself remains unanswered. The purpose of this study is to
understand to what extent perceptions regarding digital influencers’ social media content have
a stronger impact than perceptions regarding content created by brands in consumers’ both
purchase intention and online engagement with the brand. The role of brand attitude was also
analyzed in this context. 200 female respondents’ answers were analyzed through a
questionnaire.
The results showed that perceptions regarding content generated by influencers don’t have a
stronger impact than perceptions regarding content created by brands on brand attitude and
towards both consumers’ purchase intention and online engagement with beauty brands.
However, brand attitude revealed to be positively correlated with both perceptions, also having
a significant impact on consumers’ purchase intention and online engagement with the brand,
thus, it was generally a strong mediator of effects.
Consequently, brands should not replace their own social media content with content created
by influencers but work together and include them in their social media strategy.O conteúdo criado nas redes sociais pelos consumidores sobre produtos/serviços de beleza
captou a atenção das marcas desse segmento, onde alguns ascenderam a digital influencers -
revelando-se eficazes em influenciar decisões de compra. Assim, as marcas de beleza
começaram a recorrer a estes com esse propósito. A questão do conteúdo criado por influencers
ser mais eficiente em gerar outputs para marca do que o conteúdo criado pela marca em si
permanece por responder. O propósito deste estudo é perceber de que modo as perceções Ã
cerca do conteúdo gerado por influencers tem um maior impacto do que as perceções à cerca
do conteúdo criado pelas marcas na intenção de compra e na interação online com as marcas.
O papel da atitude em relação à marca foi simultaneamente analisado neste contexto. As
respostas de 200 respondentes do sexo feminino foram analisadas através de um questionário.
Os resultados mostraram que as perceções em relação ao conteúdo gerado por influencers não
têm um maior impacto que as perceções em relação ao conteúdo criado pelas próprias marcas
em ambas a intenção de compra e na interação online com as marcas. No entanto, a atitude em
relação à marca mostrou estar positivamente correlacionada com ambas as perceções, com um
impacto significativo na intenção de compra e na interação online com as marcas, e, no geral,
ter um forte efeito de mediação.
Consequentemente, as marcas não devem substituir o seu conteúdo com o conteúdo criado por
influencers, mas trabalhar em conjunto e incluÃ-los na sua estratégia
Development of nanoparticles loaded with bioactive compounds for application as nutraceuticals
Tese de mestrado integrado. Bioengenharia (Engenharia Biomédica). Universidade do Porto. Faculdade de Engenharia. 201
O mar no espaço da CPLP
Nesta introdução estabelecemos os contornos do
debate em torno do papel desempenhado pelos
Estados‑membros da CPLP nos espaços geo‑estra‑
tégicos em que se inserem. Numa primeira parte,
procedemos à definição de problemática para
numa segunda parte, apresentarmos uma recensão
crÃtica dos artigos temáticos seleccionados que
constituem este número da Nação e Defes
Elevada diferenciación genética y ausencia de hibridación entre cuatro especies de lapas (Patella spp.) revelada por loci aloenzimáticos
The occurrence of hybridisation between limpet species of the genus Patella has always been a contentious issue. Although a previous allozyme study reported high differentiation and no hybridisation between Patella vulgata Linnaeus, 1758, Patella depressa Pennant, 1777 and Patella ulyssiponensis Gmelin, 1791 along English shores, the recent finding of an mtDNA haplotype of P. depressa in a P. vulgata individual raised new doubts on this issue. To further study the possibility of hybridisation between limpet species and their level of genetic differentiation, ten allozyme loci were screened using starch gel electrophoresis for P. ulyssiponensis, P. depressa, P. vulgata and Patella rustica Linnaeus, 1758, from the Atlantic coast of the Iberian Peninsula. Our results show high differentiation between species, which could be clearly separated into different clusters with a Bayesian clustering algorithm. No significant signs of hybridisation were detected between any of the four species. Thus, the hypothesis of hybridisation between P. vulgata and P. depressa across their sympatric distribution is not supported. Two sympatric clusters were recovered within P. vulgata that could be related to Hardy-Weinberg disequilibrium found in locus MPI. Finally, due to the high level of intraspecific variability, the studied loci are interesting tools for the analysis of population structure and stock identification.La hibridación entre distintas especies de lapas del género Patella siempre ha sido un tema polémico. Aunque un estudio anterior de aloenzimas presenta una elevada diferenciación y ausencia de hibridación entre Patella vulgata Linnaeus, 1758, Patella depressa Pennant, 1777 y Patella ulyssiponensis Gmelin, 1791 en la costa inglesa, el reciente descubrimiento de un individuo de P. vulgata con un haplotipo mitocondrial de P. depressa ha planteado nuevas dudas respecto a este tema. Para estudiar más detalladamente la posibilidad de hibridación entre especies de lapas y su diferenciación genética se han analizado 10 loci aloenzimáticos por electroforesis en gel de almidón, en muestras de P. ulyssiponensis, P. depressa, P. vulgata y Patella rustica Linnaeus, 1758, de la costa atlántica de la penÃnsula Ibérica. Los resultados asà obtenidos evidencian la gran diferenciación existente entre especies, las cuales se separan claramente en distintos grupos con un algoritmo de agrupamiento Bayesiano. La ausencia de evidencias significativas de hibridación entre cualquiera de las cuatro especies estudiadas no permite respaldar la hipótesis de hibridación entre P. depressa y P. vulgata en su área de simpatrÃa. La identificación de dos grupos simpátricos en P. vulgata puede estar relacionada con el desequilibrio de Hardi-Weinberg en el locus MPI. La elevada variabilidad intra-especÃfica exhibida por los loci analizados puede convertirlos en herramientas de elevado interés para el análisis de la estructura poblacional y la identificación de reservorios
Roadmap of DNA methylation in breast cancer identifies novel prognostic biomarkers
Background
Breast cancer is a highly heterogeneous disease resulting in diverse clinical behaviours and therapeutic responses. DNA methylation is a major epigenetic alteration that is commonly perturbed in cancers. The aim of this study is to characterize the relationship between DNA methylation and aberrant gene expression in breast cancer.
Methods
We analysed DNA methylation and gene expression profiles from breast cancer tissue and matched normal tissue in The Cancer Genome Atlas (TCGA). Genome-wide differential methylation analysis and methylation-gene expression correlation was performed. Gene expression changes were subsequently validated in the METABRIC dataset. The Oncoscore tool was used to identify genes that had previously been associated with cancer in the literature. A subset of genes that had not previously been studied in cancer was chosen for further analysis.
Results
We identified 368 CpGs that were differentially methylated between tumor and normal breast tissue (∆β > 0.4). Hypermethylated CpGs were overrepresented in tumor tissue and were found predominantly (56%) in upstream promoter regions. Conversely, hypomethylated CpG sites were found primarily in the gene body (66%). Expression analysis revealed that 209 of the differentially-methylated CpGs were located in 169 genes that were differently expressed between normal and breast tumor tissue. Methylation-expression correlations were predominantly negative (70%) for promoter CpG sites and positive (74%) for gene body CpG sites. Among these differentially-methylated and differentially-expressed genes, we identified 7 that had not previously been studied in any form of cancer. Three of these, TDRD10, PRAC2 and TMEM132C, contained CpG sites that showed diagnostic and prognostic value in breast cancer, particularly in estrogen-receptor (ER)-positive samples. A pan-cancer analysis confirmed differential expression of these genes together with diagnostic and prognostic value of their respective CpG sites in multiple cancer types.
Conclusion
We have identified 368 DNA methylation changes that characterize breast cancer tumor tissue, of which 209 are associated with genes that are differentially-expressed in the same samples. Novel DNA methylation markers were identified, of which cg12374721 (PRAC2), cg18081940 (TDRD10) and cg04475027 (TMEM132C) show promise as diagnostic and prognostic markers in breast cancer as well as other cancer types.info:eu-repo/semantics/publishedVersio
Marketing relacional: satisfação na formação da lealdade do cliente
Mestrado em MarketingA revisão de literatura tem revelado grande interesse na lealdade do cliente e enfatizado cada vez mais a sua importância no sucesso de uma empresa. Simultaneamente, durante décadas, a satisfação tem sido mencionada como um importante determinante da lealdade. Paralelamente, o conceito marketing relacional tem assumido grande relevância ao nÃvel da prestação de serviços, sustentando a ideia de que as empresas podem maximizar os seus ganhos com relações duradouras com os seus clientes, passando a gestão dessas relações a estar associada à satisfação e à consequente lealdade.
Neste contexto, o presente estudo examina o efeito do grau de satisfação na formação do grau de lealdade do cliente, através de um estudo de caso de uma loja de desporto da região da Aveiro.
Os dados recolhidos, a uma amostra de 220 inquiridos, por meio de um questionário, suportam a teoria de que estes dois constructos estão relacionados entre si. Desta forma, esta investigação permitiu aferir o grau de satisfação geral e de lealdade geral dos clientes para com a loja, fornecendo evidência empÃrica da existência de uma relação positiva (moderada) entre os mesmos. Foi, ainda, possÃvel afirmar que o grau de lealdade não varia significativamente consoante determinadas caracterÃsticas do perfil dos clientes inquiridos, contudo constituem caracterÃsticas importantes para a tomada de decisão neste contexto especÃfico.The literature review has shown great interest in customer loyalty and increasingly emphasized its importance on success of a company. Simultaneously, satisfaction has often been mentioned as an important determinant of loyalty. At the same time, the relationship marketing concept has taken greater importance in terms of service delivery, supporting the idea that companies can increase their profits with long-term relationships with their customers, and the management of that relationship is associated with satisfaction and consequent loyalty.
It is in this context, the present study examines the effect of satisfaction in the formation of customer loyalty degree through a case study of a sports shop in the Aveiro region.
The data collected to a sample of 220 respondents by a questionnaire support the theory that these two constructs are correlated. Thus, this research allowed the measurement of overall satisfaction degree and overall customer loyalty degree to the store, providing empirical evidence of a positive and moderate relationship between them. It was also possible to say that loyalty degree is not significantly different comparing some characteristics of customers profile, nevertheless that characteristics are important for decision making in this specific context
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