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Exploring Design Optimization of Self-Compacting Mortars with Response Surface Methodology
Get PDFThe ever-evolving construction sector demands technological developments to provide
consumers with products that meet stringent technical, environmental, and economic requirements.
Self-compacting cementitious mixtures have garnered significance in the construction market due to
their enhanced compaction, workability, fluidity, and mechanical properties. This study aimed to
harness the potential of statistical response surface methodology (RSM) to optimize the fresh proper ties and strength development of self-compacting mortars. A self-compacting mortar repository was
used to build meaningful and robust models describing D-Flow and T-Funnel results, as well as the
compressive strength development after 24 h (CS24h) and 28 days (CS28d) of curing. The quantitative
input factors considered were A (water/cement), B (superplasticizer/powder), C (water/powder),
and D (sand/mortar), and the output variables were Y1 (D-Flow), Y2 (T-Funnel), Y3 (CS24h), and
Y4 (CS28d). The results found adjusted response models, with significant R2 values of 87.4% for the
D-Flow, 93.3% for the T-Funnel, and 79.1% for the CS24h. However, for the CS28d model, a low R2 of
39.9% was found. Variable A had the greatest influence on the response models. The best correlations
found were between inputs A and C and outputs Y1 and Y2, as well as input factors A and D for
responses Y3 and Y4. The resulting model was enhanced, thereby resulting in a global desirability of
approximately 60%, which showcases the potential for the further refinement and optimization of
RSM models applied to self-compacting mortars.info:eu-repo/semantics/publishedVersio
Autobiografia, desenraizamento e errância: Jonas Mekas em Reminiscências de uma Viagem à Lituânia
Get PDFO presente artigo foca-se na análise de Reminiscências de uma Viagem à
Lituânia (1972) e na forma como Jonas Mekas aprofunda a autobiografia em cinema
através das ideias de errância e desenraizamento. Estes conceitos têm com mote a viagem
do realizador à terra natal, após anos de emigração nos Estados Unidos. A voice over, as
derivações espaciais pelas suas memórias e lugares completam-se numa estrutura fílmica,
que apela a um modo de ver e filmar o que é “pessoal”, que vai além do que
convencionalmente tomamos como diarístico e autobiográfico.The article focus on Reminiscences of a Journey to Lithuania (1972) and the
way Jonas Mekas works autobiography in cinema, with the ideas of errant and
displacement. Both have the journey that the director did to Lithuania for the first time
after the emigration to the USA with starting point. Voice over, spatial derivations
through memories and places complete the film’s structure, which is a way of see and
film what is personal beyond what is diaristic and autobiographic.info:eu-repo/semantics/publishedVersio
Filme de família: cinema, memórias e identidades
Get PDFNo curta-metragem A gente se encontra aos domingos1
(2021), dirigido pela
própria autora, histórias ordinárias são atravessadas por questões sociais, relações
familiares e lugares; características comuns ao cinema brasileiro. Em um diálogo
intimista, em que as esferas privada e pública são interseccionadas, relatos de
experiências cinematográficas se unem às memórias pessoais e coletivas, enquadrando
lembranças constituintes da família da própria diretora. O artigo intenciona dialogar,
através dos discursos presentes no curta-metragem, com a noção de “lugares de
memória”, do historiador Pierre Nora (1993), juntamente com a articulação da teoria do
“espaço e lugar na perspectiva da experiência”, do geógrafo Yi-Fu Tuan, (1983),
passando pela “partilha do sensível”, de Jacques Rancière (2005), para desaguar nos
fragmentos da infância de Walter Benjamin (1987) e na relação entre memória e
identidade, de Joël Candau (2011).In the short movie “A gente se encontra ao domingos” (We Meet each other
on Sundays, 2021), directed by the author herself, ordinary stories are crossed by social
matters, family relations, and the feeling of belonging to different places; common issues
of the Brazilian Cinema. Through an intimate dialogue, tales of personal
cinematographic experiences gather into memories and remembrances that depict the
familiar background of the director. The paper proposes a discussion through the
discourses presented in the short movie, combining it with the idea of “places of
memory” by the historian Pierre Nora (1993), along with the theory of “space and place
in a perspective of experience” as defined by the geographer Yi-Fu Tuan (1983). The
text also calls upon the notion of “distributions of the sensible” by Jacques Rancière
(2005), passing through Walter Benjamin's childhood fragments (1987) and some
relations between memory and identity proposed by Joël Candau (2011).info:eu-repo/semantics/publishedVersio
AQUA: explorando a gamificação e ciência cidadã na monitorização da biodiversidade de cetáceos
Get PDFAo longo dos anos, as atividades humanas têm ameaçado o ecossistema marinho, e os cetáceos
têm sido uma das espécies mais afetadas. A recolha de informação é crucial para monitorizar estas
espécies e, posteriormente, tomar medidas em relação às políticas e iniciativas de conservação.
Recentemente, o potencial dos dados recolhidos através da ciência cidadã tem sido explorado como
uma oportunidade rápida e económica para recolher informações sobre avistamentos de cetáceos.
Em particular, nas ilhas da Macaronésia, iniciativas têm procurado envolver embarcações turístico marítimas na recolha destes dados durante atividades de observação de cetáceos, estabelecendo uma
parceria entre cientistas e empresas para promover o conhecimento sobre a biodiversidade marinha.
No entanto, esta recolha de dados é feita em papel por biólogos que acompanham as embarcações,
tornando difícil centralizar todas as informações e garantir a participação contínua.
Esta dissertação foca-se em melhorar o desenho e desenvolvimento de uma aplicação móvel de
ciência cidadã projetada para facilitar a recolha e partilha de informações sobre avistamentos de
cetáceos. Uma vez que a revisão de literatura destaca que um desafio comum na ciência cidadã
é manter a motivação dos participantes ao longo do tempo, este trabalho integrou elementos de
gamificação na aplicação.
Foi realizada uma avaliação do protótipo com profissionais durante viagens de observação de ce táceos e os nossos resultados indicam que, embora a gamificação não tenha aumentado a motivação
dos participantes, a experiência de utilizador da aplicação foi muito positiva, com os participantes
a destacar a facilidade de utilização, a simplicidade do processo de recolha de dados e a relevância
da gamificação para entusiastas.
Além disso, este trabalho também contribuiu para o desenvolvimento de uma API que permite
partilhar dados recolhidos a partir da aplicação móvel com entidades externas, contribuindo para
a partilha dos dados das espécies. Este trabalho aponta possíveis caminhos para investigações
futuras, considerando o potencial e a utilidade do sistema AQUA, que combina ciência cidadã,
tecnologia e ciência na monitorização da biodiversidade de cetáceos.Over the years, human activities have threatened the marine ecosystem, and cetaceans have been
one of the most affected species. Gathering information is crucial for monitoring these species and,
ultimately, taking action regarding conservation policies and initiatives. Recently, the potential
of data collected through citizen science has been explored as a rapid and cost-effective opportu nity to gather data on cetacean sightings. Particularly, in the Macaronesia islands, initiatives have
sought to involve tourist maritime vessels in collecting this data during whale-watching activities,
establishing a partnership between scientists and companies to promote learning about marine bio diversity. However, this data collection is done in a paper-based format by biologists accompanying
the vessels, making it difficult to centralize all the information and ensure continuous participation.
This dissertation focuses on refining the design and development of a citizen science mobile
application designed to facilitate the collection and sharing of information about cetacean sightings.
Since the literature review highlighted that a common challenge in citizen science is sustaining
participants’ motivation over time, this work integrated gamification elements into the application.
A prototype evaluation was conducted with professionals during whale-watching trips and our
findings indicate that while the gamification did not increase participants’ motivation, the applica tion’s user experience was very positive, with participants highlighting its ease of use, the seamless
data collection process and the relevance of gamification for enthusiasts.
Furthermore, this work also contributed to the development of an API that allows for sharing
data collected from the mobile application with external entities, contributing to the dissemination
of the species data. This work points towards possible avenues for future research, considering the
potential and usefulness of the AQUA system, which combines citizen science, technology, and
science in marine biodiversity monitoring
Influence of cold pre-fermentation maceration on the volatilomic pattern and aroma of white wines
Get PDFAroma compounds play a key role in wine quality due to their importance in wine aroma. The aim of the present study is to investigate the influence of cold pre-fermentative maceration (CPM) treatment on aromatic and sensory properties of white wines from four grape varieties (Tempranillo Blanco, Maturana Blanca, Viura and Garnacha Blanca) during two consecutive years (2019 and 2020). A total of 62 aroma compounds belonging to different chemical families were identified using headspace solid-phase microextraction combined with gas chromatography mass spectrometry (HS-SPME/GC-MS). CPM treatment enhanced the total relative concentration of alcohols, esters and acids compared to control wines. Regarding sensorial properties, esters made the greatest contribution to the studied white wines, mainly through the development of floral and fruity notes. On the other hand, CPM treatment did not significantly influence the total relative concentration of terpenoids, and different trends were observed according to grape variety and vintage. The obtained results showed differences in the wine’s aromatic complexity according to the grape variety, the vintage and the treatment applied and suggested that CPM treatment could represent a suitable approach to manipulate the aromatic profile and enhance the aromatic quality and complexity of wine.</jats:p
The fingerprint of fortified wines—From the sui generis production processes to the distinctive aroma
Get PDFThe fortified wines that originated in Mediterranean countries have, in common, a high alcohol content to increase their shelf-life during long journeys to northern Europe and the American continent. Nowadays, the world’s better-known wines, including Marsala, Madeira, Port, and Sherry, due to their high alcoholic content, sweet taste, and intense aromatic profile, are designated as dessert wines and sometimes served as aperitifs. This review gives an overview of the traditional vinification process, including the microbiota and autochthonous yeast, as well as the regulatory aspects of the main Italian, Portuguese, and Spanish fortified wines. The winemaking process is essential to defining the volatile organic compounds (VOCs) that characterize the aroma of each fortified wine, giving them an organoleptic fingerprint and “terroir” characteristics. The various volatile and odorous compounds found in fortified wines during the oxidative aging are discussed in the last part of this review.</jats:p
Hikes and trails systematization of the types of obstacles/adaptations in pedestrian routes
Get PDFHikes and trails are increasingly popular activities, in the field of tourism, but also at the level of recreational activities. With
this work, we intend to create an integrative vision of the activity that includes the Situation / Context / Individual, which allows
the development of instruments in order to enable an intervention, with a functional character, in this type of activities. To this end,
we have systematized a set of adaptations requested from individuals, characteristics in the pedestrian paths, using the existing
bibliography and an analysis of the obstacles identified in the activities
Evaluation of the transfer and occurrence of opium alkaloids in poppy seed teas using preconcentrations with µSPEed® followed by GC-MS analysis
Get PDFIntoxication due to the consumption of poppy seed teas has been reported due to their contamination with opium alkaloids (OAs). In this work, an efficient methodology based on microsolid-phase extraction (µSPEed®) followed by gas chromatography–mass spectrometry (GC-MS) has been optimized to quantify five OAs in poppy seed teas. Nine cartridges (C4, C8, C18, silica, APS, PFAs, PS/DVB-RP, PS/DVB-SCX and PS/DVB-SAX), pH levels, cycles and elution solvents were evaluated. The method was validated and applied to study the transfer of OAs by evaluating water temperatures, infusion times and seed amounts. The highest transfer rates (71% for morphine, 96% for thebaine, and 100% for codeine, noscapine and papaverine) were achieved at 90°C, 5 min, with 4 g. These conditions were used to quantify the OAs in four teas prepared from different seeds. A high amount of morphine (1563 µg/L) was found in one tea, indicating that the seeds had a concentration twice the maximum limit, highlighting the need to warn the population of this dangerous practice.</jats:p
E a memória vos libertará: o lugar da memória visto no documentário Democracia em Vertigem
Get PDFDemocracia em Vertigem (2019), dirigido por Petra Costa, é um documentário
em primeira pessoa que traçou a relação dela com o Brasil, com a memória de sua família
e a conexão desses pontos com o impeachment da presidente Dilma Rousseff, em 2016,
e a ascensão de Jair Bolsonaro. Para amparar o papel da autobiografia, a diretora explorou
algumas noções de lugar e memória trabalhados por Pierre Nora, além de ideias sobre o
esquecimento desenvolvidas por Marc Augé e Paul Ricoeur. Esses temas orbitam em
torno de conceitos cinematográficos de Bill Nichols e André Bazin. O artigo, portanto,
vai observar como Petra trabalhou tais pontos para elucidar o passado, o presente e o
futuro do Brasil.Democracia em Vertigem (2019), directed by Petra Costa, is a first-person
documentary that traced her relationship with Brazil, with the memory of her family and
the connection of these points with the impeachment of President Dilma Rousseff, in 2016,
and the rise of Jair Bolsonaro. To expand the role of autobiography, the director explored
some notions of place and memory worked on by Pierre Nora, as well as ideas about
forgetting made by Marc Augé and Paul Ricoeur. These themes orbit around the
cinematographic concepts of Bill Nichols and André Bazin. The article, therefore, will
observe how Petra worked on these points to elucidate the past, present and future of
Brazil.info:eu-repo/semantics/publishedVersio
Tracing the volatilomic fingerprint of grape pomace as a powerful approach for its valorization
Get PDFThe huge amount of grape pomace (GP) generated every year worldwide, particularly in Europe, creates negative
impacts at the economic and environmental levels. As far as we know, scarce research has been done on the
volatilomic fingerprint of GP. To meet consumer demand for healthy foods, there is a growing interest in the
characterization of particular volatile organic metabolites (VOMS) in GP that can be used for industrial appli cations, including the food industry. In this study, the volatilomic fingerprint of GP obtained from different Vitis
vinifera L. grapes was established by solid phase microextraction (HS-SPME) combined to gas chromatography mass spectrometry (GC-MS), to explore the properties of most dominant VOMs in a context of its application on
marketable products. A total of 52 VOMs belonging to different chemical families were identified. Alcohols,
carbonyl compounds, and esters, are the most dominant, representing 38.8, 29.3, and 24.2% of the total volatile
profile of the investigated GP, respectively. Esters (e.g., isoamyl acetate, hexyl acetate, ethyl hexanoate) and
alcohols (e.g., 3-methyl butan-2-ol, hexan-1-ol) can be used as flavoring agents with potential use in the food
industry, and in the cosmetic industry, for fragrances production. In addition, the identified terpenoids (e.g.,
menthol, ylangene, limonene) exhibit antioxidant, antimicrobial, and anticancer, biological properties, among
others, boosting their potential application in the pharmaceutical industry. The obtained results revealed the
potential of some VOMs from GP to replace synthetic antioxidants, colorants, and antimicrobials used in the food
industry, and in the cosmetic and pharmaceutical industry, meeting the increasing consumer demand for natural
alternative compounds