985 research outputs found
Plant extracts: isolation, characterization, nanoencapsulation in lipids, cytotoxicity in AGS cells and synthesis of analogues
Dissertação de mestrado em Química MedicinalThere is growing interest in plants as a potential source of bioactive molecules with
application in different areas, from cosmetics to pharmaceuticals, as well as in the food
industry. It is possible to extract phytochemicals by different extraction techniques, as well as
to isolate and determine their composition using characterization techniques.
Despite their high interest, many of the phytochemicals have some limitations on their
potential use due to high volatility and/or easy degradation when exposed to air. In this
perspective, nanoencapsulation of these compounds allows their preservation and controlled
release in the body are currently of interest.
In this work three different species, Ginkgo biloba, Foeniculum Vulgare and Chelidonia
majus. were subjected to Soxhlet extraction and the extracts obtained were purified and
characterized. Ginkgolic acid, estragole and coptisine have been identified in Ginkgo Biloba,
F. Vulgare and Chelidonia majus, respectively. In order to obtain derivatives of the isolated
compounds reactivity studies were performed using ginkgolic acid and estragole. Methylated
ginkgolic acid and dioxinone, as well as epoxide derivatives were obtained from ginkgolic acid
and estragole, respectively. Characterization of the synthesized compounds was carried out
using NMR (
1H and 13C), and IR spectroscopies, HPLC-DAD and mass spectrometry.
Extracts from F. vulgare and C. majus as well as estragole and coptisine were subjected
to encapsulation assays using soybean lecithin by ethanolic injection method.
Furthermore biological activity studies have been performed to assess the toxicity of
the extracts/compounds obtained using AGS cell line through MTT and LDH assays.É cada vez maior o interesse nas plantas como potencial fonte de moléculas bioativas
com aplicação em diferentes áreas, desde a cosmética aos fármacos, bem como na indústria
alimentar. É possível extrair fitoquímicos por diferentestécnicas de extração, bem como isolar
e determinar a sua composição recorrendo a técnicas de caracterização.
Apesar do seu elevado interesse, muitos dos fitoquímicos apresentam algumas
limitações quanto ao seu potencial, devido à elevada volatilidade, assim como à fácil
degradação quando expostos ao ar. Nesta perspetiva, técnicas de nanoencapsulamento deste
tipo de compostos que permitam a sua preservação e libertação controlada no organismo são
atualmente alvo de interesse.
Neste trabalho, três espécies diferentes, Ginkgo biloba, Foeniculum vulgare e
Chelidonia majus foram submetidas à extração por Soxhlet e os extratos obtidos foram
purificados e caracterizados. O ácido ginkgólico, o estragole e a coptisina foram identificados
nos extratos de Ginkgo Biloba, F. vulgare e Chelidonia majus, respetivamente. De modo a
obter derivados dos compostos isolados, realizaram-se estudos de reatividade utilizando o
ácido ginkgolico e o estragole. O ácido ginkgólico metilado e a dioxinona, assim como o
epóxido foram obtidos a partir do ácido ginkgólico e do estragole, respectivamente. A
caracterização dos compostos sintetizados foi realizada utilizando as espectroscopias de RMN
(
1H e 13C), IV, HPLC-DAD e espectrometria de massa.
Extratos de F. vulgare e C. majus, bem como estragol e coptisina, foram submetidos a
ensaios de encapsulamento utilizando lecitina de soja por injeção etanólica.
Foram ainda realizados estudos de atividade biológica para avaliar a toxicidade dos
extratos/compostos obtidos utilizando a linha celular AGS através de ensaios de MTT e LDH.I would also like to thank the entire Department of Chemistry/Chemistry Centre of the
University of Minho, which provided me with all the means for such experiments, and also the
Laboratory of Pharmacognosy of the Department of Chemical Sciences of the Faculty of
Pharmacy/REQUIMTE of the University of Porto and the Department of Physics/Physics Centre
of the University of Minho.Thanks are also due to Fundação para a Ciência e Tecnologia (FCT Portugal) and FEDER through the project PTDC/ASP-AGR/30154/2017
The devil wears Prada : counterfeit in luxury goods
All over the world, the market of luxury products has been significantly increasing. Following an almost parallel trend, the grey market of counterfeit luxury goods, has also been exponentially growing. To fight against this tendency, and to avoid losing a relevant part of their business, luxury brands need to develop new strategies. Such strategies can be directed not to fight the black market itself, but to better understand consumers’ perception of luxury items and try to change consumer perception about counterfeit goods. To try to understand consumers’ perception and to see their reaction to a threat, this thesis compiled a comprehensive online survey, where participants faced several scenarios with luxury and counterfeit goods. Besides, in half of the scenarios, participants were exposed to a self-threat. The results showed that threatened consumers tend to better accept counterfeit in luxury goods while increasing their sense of fashionable to protect their identity. However, when they were threatened their likelihood to purchase luxury perfumes surprisingly decreased. Consumers’ age influenced the likelihood to purchase a counterfeit luxury perfume in the same way as current occupation and monthly income influenced the likelihood to purchase a counterfeit luxury handbag. The results also showed that consumers that relate a high value-expressive function to genuine luxury goods, have more sensitive moral beliefs from other people buying counterfeit luxury goods. It was also concluded that consumers’ are willing to pay more for some product that may restore their self-image previously threatened.O mercado dos produtos de luxo e o mercado da contrafação dos mesmos tem sofrido um aumento significativo. Para combater esta tendência e para evitar perdas de negócio, as marcas de luxo têm de começar a desenvolver novas estratégias. Estas, não podem ser unicamente direcionadas ao combate do mercado clandestino em si, mas sim para uma melhor compreensão das perceções dos consumidores sobre os produtos de luxo e na tentativa de mudar as suas perceções sobre os produtos contrafeitos. Para perceber as perceções dos consumidores e analisar como reagem quando são ameaçados, esta tese foi elaborada com base num questionário online, onde os participantes enfrentaram diferentes cenários com produtos de luxo e produtos contrafeitos. Simultaneamente, em metade dos cenários, os participantes foram sujeitos a uma ameaça à sua personalidade. Os resultados mostraram que os consumidores ameaçados tendem a aceitar melhor os produtos contrafeitos como forma de aumentar o seu sentido de moda para proteger a sua identidade. Surpreendentemente, a probabilidade de comprarem perfumes de luxo diminuiu. A idade dos consumidores influenciou a probabilidade de comprarem perfumes contrafeitos da mesma forma que a ocupação atual e salário mensal influenciaram a probabilidade de comprarem malas de luxo contrafeitas. Os resultados também mostraram que os consumidores que associam a função de valor expressivo aos produtos de luxo, são mais sensíveis nas suas convicções morais sobre as outras pessoas comprarem produtos contrafeitos. Foi também concluído que os consumidores estão dispostos a pagar mais por produtos que possam restaurar a sua imagem, quando previamente ameaçada
Maturity Models Architecture: A large systematic mapping
Maturity models are widespread in research and in particular, IT practitioner communities. However, theoretically sound, methodologically rigorous and empirically validated maturity models are quite rare. This systematic mapping paper focuses on the challenges faced during the development of maturity models. More specifically, it explores the literature on maturity models and standard guidelines to develop maturity models, the challenges identified and solutions proposed. Our systematic mapping revealed over six hundred articles on maturity models. Extant literature reveals that researchers have primarily focused on developing new maturity models pertaining to domain-specific problems and/or new enterprise technologies. We find rampant re-use of the design structure of widely adopted models such as Nolan’s Stage of Growth Model, Crosby’s Grid, and Capability Maturity Model (CMM). We also identify three dominant views of maturity models and provide guidelines for various approaches to constructing maturity models with a standard vocabulary. We finally propose using process theories and configurational approaches to address the main theoretical criticisms with regard to maturity models and conclude with some recommendations for maturity model developers
The role of digital marketing: a perspective from Porto hotels’ managers
The role of internet in the purchasing behavior of tourists led to a modification in marketing
plans that became increasingly digital. This study aims to identify how managers of the
hospitality industry use digital marketing, as a marketing tool.
This study adopted a qualitative methodology comprising: a) the analysis of the online presence
- website, Facebook, Instagram, Twitter, Booking.com and TripAdvisor - of the 59 four and five
stars establishments of Porto; b) semi-structured interviews that were conducted to managers
and marketers of the 32 hotels in study. Digital marketing tools provide numerous benefits to
the hospitality industry. However, managers still do not take advantage of their full potential.
In digital marketing, the performance indicators are always evolving. Although the data were
collected at the end of 2016, we think that the conclusions and recommendations still are
updated and relevant. This study suggests some recommendations for improving the digital
marketing performance of Porto hotels’. Although adopting a case-study approach, this paper
provides an extensive assessment of digital marketing communication mix regarding the luxury
segment of hotel industry. Moreover, this assessement is made for all units within a city scale.info:eu-repo/semantics/publishedVersio
Exploring the nature of the gender-congruency effect: implicit gender activation and social bias
The aim of the study was to explore the nature of the gender-congruency
effect, characterized by a facilitation on the processing of congruent words in
grammatical gender. Moreover, we explored whether resemblances between
gender identities and gender attitudes with grammatical gender modulated
lexical processing. We designed a gender-priming paradigm in Spanish, in which
participants decided the gender of a masculine or feminine pronoun preceded
by three different primes: biological gender nouns (mapping biological sex),
stereotypical nouns (mapping biological and stereotypical information), and
epicene nouns (arbitrary gender assignment). We found faster processing of
gender congruent pronouns independently of the type of prime, showing that
the grammatical gender feature is active even when processing bare nouns
that are not conceptually related to gender. This indicates that the gendercongruency
effect is driven by the activation of the gender information at the
lexical level, which is transferred to the semantic level. Interestingly, the results
showed an asymmetry for epicene primes: the gender-congruency effect was
smaller for epicene primes when preceding the feminine pronoun, probably
driven by the grammatical rule of the masculine being the generic gender.
Furthermore, we found that masculine oriented attitudes can bias language
processing diminishing the activation of feminine gender, which ultimately could
overshadow the female figureFEDER/Junta
de Andalucía-Consejería de Economía y Conocimiento (A-SEJ-
416-UGR20)The Ministry of Science and
Innovation (PID2019- 111359GBI00/AEI/10.13039/501100011033
The new words kids hear from translated picturebooks
This study shows how the language in translated picturebooks is enriched by the use of rare words. We document how the translation of picturebooks from English to Portuguese results in the use of rare words in Portuguese. Evidence indicates that children learn new vocabulary through readings of picturebooks (Noble et al., 2019) and that translators make choices that contribute to the use of rare words (Ketola, 2018). The sample of 86 picturebooks was selected from a list recommended by the Portuguese national reading plan for 3-5-year-olds. The identification of rare words was done using a frequency analysis in both Portuguese, using ESCOLEX, and English, using the ChildFreq tool. Findings indicate that translated picturebooks use rich and varied lexicon and include an average of 6.6 rare words. Twenty-two percent of these words originate from literal and non-literal translations and are not rare in the original texts. This indicates that the process of translation contributes to increasing children's exposure to rare words.info:eu-repo/semantics/publishedVersio
Novel therapies against aggressive differentiated thyroid carcinomas
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