166 research outputs found
Ontologies learn by searching
Dissertation to obtain the Master degree in Electrical Engineering and Computer ScienceDue to the worldwide diversity of communities, a high number of ontologies representing the same segment of reality which are not semantically coincident have appeared. To solve this problem, a possible solution is to use a reference ontology to be the intermediary in the communications between the community enterprises and to outside. Since semantic mappings between enterprise‘s ontologies are established, this solution allows each of the enterprises to keep internally its own ontology and semantics unchanged. However information systems are not static, thus established mappings become obsoletes with time. This dissertation‘s objective is to identify a suitable method that combines semantic mappings with user‘s feedback, providing an automatic learning to ontologies & enabling auto-adaptability and dynamism to the information system
Cellulose biomodification with cutinase fusion proteins
The textile industry presents well succeed examples of
enzyme applications on the processing of natural fi
bres. The design of
hybrid enzymes mimics the strategies that Nature uses to evolve and it
is a powerful tool in biotechnology. The production and application of
the cutinase fused to carbohydrate
-
binding modules (CBMs) has
provided strong evidences of bei
ng an interesting strategy to pursuit.
The CBMs act synergistically with the catalytic domains by increasing
the effective enzyme concentration at the substrate surface and, for
some CBMs, by physical disruption of the solid substrate. Future work
is neede
d to improve the recombinant production of modular cutinases
and to study in detail their affinities toward the cellulose substrates
Enzymatic polymerization of phenolic compounds
Phenolics are natural compounds which contains hydroxyl group bonded to aromatic
hydrocarbon ring. These compounds can be divided into two categories depending on
the oxidation state of the central pyran ring: flavonoids and non-flavonoids. It is important to highlight the excellent properties of the phenolic compounds, such as anti-inflammatory, antimicrobial, and antioxidant activity. It has been described that the oxidation of phenolic compounds enhances its antimicrobial properties since the resulting polymers can contribute to the microorganism’s toxification. The polymerization reaction can be achieved by different biocatalysts such as oxidoreductases, namely laccases and peroxidases. Laccases use molecular oxygen as a co-substrate, being therefore the perfect co-substrate. Depending on the structure of the phenolic compound, namely the number of hydroxyl groups, the enzymatic polymerization can be performed via laccase or using laccase-mediator systems (LMSs). On the first reaction, the phenolic compound is oxidized and the resulting phenoxy radicals conduct to polymers formation through recombination processes. On the second method, the phenolic compound oxidation is mediated by redox species yielding the polyphenols formation. Any of these two routes allows the polymerization of phenolic products with enhanced properties
Biotechnological applications of mammalian odorant-binding proteins
The olfactory system of mammals allows the detection and discrimination of thousands of odors from the environment. In mammals, odorant-binding proteins (OBPs) are considered responsible to carry odorant molecules across the aqueous nasal mucus to the olfactory receptors (ORs). The three-dimensional structure of these proteins presents eight antiparallel ?-sheets and a short ?-helical segment close to the C terminus, typical of the lipocalins family. The great ability of OBPs to bind differentiated ligand molecules has driven the research to understand the mechanisms underlying the OBP function in nature and the development of advanced biotechnological applications. This review describes the role of mammalian OBPs in the olfactory perception, highlighting the influence of several key parameters (amino acids, temperature, ionic strength, and pH) in the formation of the OBP/ligand complex. The information from the literature regarding OBP structure, affinity, the strength of binding, and stability inspiring the development of several applications herein detailed.This study was financially supported by the Portuguese Foundation for Science and Technology (Fundac¸~ao para a Ciencia e a Tecnologia) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation [NORTE-01-0145-FEDER-000004] funded by European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte. F.G. thanks Fundac~ao para a Ci^
encia e a Tecnologia for their funding [SFRH/BD/114684/2016].info:eu-repo/semantics/publishedVersio
Decolourization of paprika dye effluent with hydrogen peroxide produced by glucose oxidase
Hydrogen peroxide was produced from bran by a two-step process using cellulase/xylanase and glucose oxidase, sequentially. The decolourization efficiency of the produced reagent was tested using paprika oil dye (effluent from industrial source) and high levels of colour removal (96%) were achieved after saponification pre-treatment and hydrogen peroxide application. The method is economically and environmentally advantageous since lower energy and chemical input are needed and wastewater pollution is considerably reduced. At the same time, the utilization of waste materials was successfully achieved.The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the article. Carla Silva would like to acknowledge the Portuguese Fundacao para a Ciencia e a Tecnologia (FCT) for funding under the scholarship SFRH/BPD/46515/2008
A comprehensive review of mammalian pigmentation: paving the way for innovative hair colour-changing cosmetics
The natural colour of hair shafts is formed at the bulb of hair follicles, and it is coupled to the hair growth cycle. Three critical processes must happen for efficient pigmentation: (1) melanosome biogenesis in neural crest-derived melanocytes, (2) the biochemical synthesis of melanins (melanogenesis) inside melanosomes, and (3) the transfer of melanin granules to surrounding pre-cortical keratinocytes for their incorporation into nascent hair fibres. All these steps are under complex genetic control. The array of natural hair colour shades are ascribed to polymorphisms in several pigmentary genes. A myriad of factors acting via autocrine, paracrine, and endocrine mechanisms also contributes for hair colour diversity. Given the enormous social and cosmetic importance attributed to hair colour, hair dyeing is today a common practice. Nonetheless, the adverse effects of the long-term usage of such cosmetic procedures demand the development of new methods for colour change. In this context, case reports of hair lightening, darkening and repigmentation as a side-effect of the therapeutic usage of many drugs substantiate the possibility to tune hair colour by interfering with the biology of follicular pigmentary units. By scrutinizing mammalian pigmentation, this review pinpoints key targetable processes for the development of innovative cosmetics that can safely change the hair colour from the inside out.The authors thank the support of the Portuguese Foundation for Science and Technology (FCT), under the scope of the strategic funding of the UIDB/04469/2020 unit, and LABBELS—
Associate Laboratory in Biotechnology, Bioengineering and Microelectromechnaical Systems, LA/P/
0029/2020. The author Bruno Fernandes also acknowledges his PhD scholarship funded by FCT
(SFRH/BD/131824/2017).info:eu-repo/semantics/publishedVersio
Release of fragrances from cotton functionalized with carbohydrate-binding module proteins
Perspiration as a response to daily activity and physical exercise results in unpleasant odors that cause social unrest and embarrassment. To tackle it, functional textiles incorporating fragrances could be an effective clothing deodorizing product. This work presents two strategies for the release of -citronellol from functionalized cotton with carbohydrate-binding module (CBM)-based complexes (OBP::GQ20::CBM/-citronellolapproach 1 and CBM::GQ20::SP-DS3-liposome/-citronellolapproach 2). CBM from Cellulomonas fimi was fused with the odorant-binding protein (OBP::GQ20::CBM) and with an anchor peptide with affinity to the liposome membrane (CBM::GQ20::SP-DS3). In approach 1, OBP fusion protein served as a fragrance container, whereas in approach 2, the fragrance was loaded into liposomes with a higher cargo capacity. The two strategies showed a differentiated -citronellol release profile triggered by an acidic sweat solution. OBP::GQ20::CBM complex revealed a fast release (31.9% and 25.8% of the initial amount, after 1.5 and 24 h of exposure with acidic sweat solution, respectively), while the CBM::GQ20::SP-DS3-liposome complex demonstrated a slower and controlled release (5.9% and 10.5% of the initial amount, after 1.5 and 24 h of exposure with acidic sweat solution, respectively). Both strategies revealed high potential for textile functionalization aimed at controlled release of fragrances. The OBP::GQ20::CBM/-citronellol complex is ideal for applications requiring fast release of a high amount of fragrance, whereas the CBM::GQ20::SP-DS3-liposome/-citronellol complex is more suitable for prolonged and controlled release of a lower amount of -citronellol.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. F.G. and C.S. thanks FCT for their funding (SFRH/BD/114684/2016; SFRH/IF/00186/2015).info:eu-repo/semantics/publishedVersio
Assessment of data-driven modeling strategies for water delivery canals
Conferência: CONTROLO’2012 - 16-18 July 2012 - FunchalThe aim of this work is to develop nonlinear dynamical models for the canal system of Núcleo de Hidráulica e Controlo de Canais. The canal is a nonlinear system and thus should be modeled to meet given operational requirements, while capturing all relevant system dynamics, such as the resonance waves created due to the movements of gates, and also contributing to the controller precision. The nonlinear modeling is based on data-driven methods, namely Composite Local Linear Models, Fuzzy Models and Artificial Neural Networks. These models are identified using data collected from the experimental facility, and their performance is assessed based on suitable validation criteria. The modeling results show the effectiveness of these models while capturing all significant dynamics for the canal system
Tarefas matemáticas em diferentes contextos escolares
Dissertação de mestrado, Ensino da Matemática no 3.º Ciclo do Ensino Básico e Ensino Secundário, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015No presente relatório descrevo o meu percurso profissional desde a conclusão da licenciatura em Matemática, em 2001 até ao presente. Procuro, em simultâneo com a descrição de alguns momentos da minha caminhada, fazer uma reflexão crÃtica sobre o meu percurso ao longo destes 14 anos. O envolvimento, em diversas experiências e projetos, proporcionaram-me aprendizagens só possÃveis através da prática. O perÃodo que decorre deste a conclusão da minha licenciatura até ao atual momento, inclui longos perÃodos de espera por uma colocação, à lecionação de turmas do ensino básico e secundário, nos mais variados cursos. Deste modo, o percurso percorrido até à data permitiu-me conhecer uma diversidade de contextos escolares: com alunos do ensino regular, currÃculos alternativos e à reeducação de adultos, neste último caso, em meio prisional. Hoje, posso afirmar que muito mais do que o conhecimento cientÃfico adquirido na formação inicial, o professor necessita de desenvolver uma diversidade de conhecimentos e competências, jamais previstas na formação académica.
Na segunda parte deste relatório apresento uma experiência de ensino desenvolvida em duas turmas de Educação e Formação de Adultos em meio prisional. A seleção das tarefas, em qualquer contexto de ensino, seja numa turma de ensino regular ou de currÃculos alternativos, requer a sua adequação à s caracterÃsticas e ao contexto em que os alunos estão integrados. No contexto prisional o ensino/aprendizagem da matemática está sujeito a um conjunto de procedimentos, regras e estratégias muito peculiares. Respeitando as exigências associadas a este contexto especÃfico, optei por realizar uma experiência de ensino que envolveu a resolução de problemas. Foi proposta uma sequência de problemas não diretamente relacionados com conteúdos programáticos, como estratégia para desenvolver as competências estabelecidas no Referencial de Competências-Chave (Alonso et al., 2002). A análise dos dados mostra que apesar das inúmeras dificuldades, os formandos mostraram interesse e gosto pelas atividades matemáticas apresentadas
Prescribing-Assessment Tools for Long-Term Care Pharmacy Practice: Reaching Consensus through a Modified RAND/UCLA Appropriateness Method
Supplementary Materials - The following are available online at https://www.mdpi.com/article/10.3390/pharmacy9040194/s1, Table S1: Summary of the identified Prescribing-Assessment Tools.Medicines are the most used health technology in Long-Term Care. The prevalence of potentially inappropriate medicines amongst Long-Term Care patients is high. Pharmacists, assisted by prescribing-assessment tools, can play an important role in optimizing medication use at this level of care. Through a modified RAND/UCLA Appropriateness Method, 13 long-term care and hospital pharmacists assessed as ‘appropriate’, ‘uncertain’, or ‘inappropriate’ a collection of commonly used prescribing-assessment tools as to its suitability in assisting pharmacy practice in institutional long-term care settings. A qualitative analysis of written or transcribed comments of participants was pursued to identify relevant characteristics of prescribing-assessment tools and potential hinders in their use. From 24 different tools, pharmacists classified 9 as ‘appropriate’ for pharmacy practice targeted to long-term care patients, while 3 were classified as ‘inappropriate’. The tools feature most appreciated by study participants was the indication of alternatives to potentially inappropriate medication. Lack of time and/or pharmacists and limited access to clinical information seems to be the most relevant hinders for prescribing-assessment tools used in daily practice.info:eu-repo/semantics/publishedVersio
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