160 research outputs found
How banks price loans for LBOs: an empirical analysis of spread determinants
This paper examines which factors determine the pricing of loans for LBOs, using a worldwide sample of 11,111 loans closed in the 2000–2016 period. Our findings are consistent with the hypotheses that loans for LBOs extended to borrowers in market- versus bank-based financial systems are differently priced, and that law and institutional characteristics are important determinants of spreads for deals closed in market-oriented countries. Despite LBO loan pricing differing significantly in normal versus crisis times, loans extended to borrowers in market-based financial systems have higher spreads than those where banks play a major role. Our results also support the hypothesis of tranching as a mechanism of reducing spreads by completing financial markets and mitigating informational asymmetries. Finally, a robust convex relationship between spread and maturity is found, suggesting higher market competition by banks and investors for standard, medium-term maturities.info:eu-repo/semantics/acceptedVersio
Impact of organizational factors on accident prediction in the retail sector
Although different actions to prevent accidents at work have been implemented in companies, the number of accidents at work continues to be a problem for companies and society. In this way, companies have explored alternative solutions that have improved other business factors, such as predictive analysis, an approach that is relatively new when applied to occupational safety. Nevertheless, most reviewed studies focus on the accident dataset, i.e., the casualty’s characteristics, the accidents’ details, and the resulting consequences. This study aims to predict the occurrence of accidents in the following month through different classification algorithms of Machine Learning, namely, Decision Tree, Random Forest, Gradient Boost Model, K-nearest Neighbor, and Naive Bayes, using only organizational information, such as demographic data, absenteeism rates, action plans, and preventive safety actions. Several forecasting models were developed to achieve the best performance and accuracy of the models, based on algorithms with and without the original datasets, balanced for the minority class and balanced considering the majority class. It was concluded that only with some organizational information about the company can it predict the occurrence of accidents in the month ahead.USDA - U.S. Department of Agriculture(PCIF/GRF/0141/2019)The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CeDRI (UIDB/05757/2020 and UIDP/05757/2020), ALGORITMI UIDB/00319/2020 and SusTEC (LA/P/0007/2021). This work has been supported by NORTE-01-0247-FEDER-072598 iSafety: Intelligent system for occupational safety and well-being in the retail sector. Inˆes Sena was supported by FCT PhD grant UI/BD/153348/2022
Developing tools for the e-learning platform mathE
MathE (mathe.pixel-online.org) is an e-learning platform for higher education developed and implemented by a consortium of seven institutional partners from five European countries. The aim of the project is to enhance the quality of teaching and improve pedagogies and assessment methods by facilitating the identification of students’ gaps in Math, providing appropriate digital tools and promoting self-evaluation with immediate feedback. The Polytechnic Institute of Bragança (IPB), in Portugal, is one of the consortium members: sixteen of its teachers collaborate in the development of this platform, being responsible for thirteen of the topics/subtopics in which the platform is structured. Such topics cover a wide range of contents, from linear transformations to integration, from graph theory to probabilities. The articulation of the topics of the MathE collection corresponds to the canonic mathematics content of engineering, business and education degrees. The MathE platform is organized into three main sections: Student´s Assessment, MathE Library and Community of Practice. So far, IPB has already developed a collection of around 800 questions for the student´s assessment section and is currently developing the MathE Library. More than 350 students from IPB are using the MathE platform; some offered as volunteers, whose role is testing the behavior of the platform as well as looking for bugs and other details that require improvement, while others are already using the platform in their study. The feedback received up until now is quite encouraging.info:eu-repo/semantics/publishedVersio
Relógio Digital com Horas Minutos e Segundos
Este relógio, tal como muitos outros montados no laboratório, foi elaborado
inicialmente para os antigos dias da UBI (1997-2011).
Posteriormente foram usados nas semanas de promoção e divulgação da UBI
(2012 – 2013).
Ultimamente foram remontados com melhor qualidade e aspecto, sendo usados
na Academia Júnior das Ciências (2014 - dias de hoje).
Estes circuitos científico – pedagógicos também têm sido usados nos Dias da
Ciência Viva, Semana das Ciências e Escolas de Verão.
Estes projectos proporcionam, que algumas amostras dos componentes do
laboratório de Electrónica e Sistemas Digitais criem protótipos reais, à disposição
da comunidade (júnior, universitária e sénior).
Neste trabalho mostramos o relógio digital com o mostrador das horas (0 – 23h),
minutos (0 – 59m) e segundos (0 – 59s).
Este relógio digital, que se mostra na Fig.1, tal como outros tipos de relógio, é
constituído pelo oscilador (marcador temporal de 1 s) LS629. Depois, neste caso,
temos 6 contadores BCD, 6 descodificadores BCD para 7 segmentos, 6 packs de 8
resistências de 1k e 6 displays de 7 segmentos com ponto decimal.
Este relógio foi montado no laboratório de Electrónica do dep. Física da UBI.
Possui uma boa configuração e boa estabilidade, que é semelhante aos modelos
comerciais.
Este protótipo laboratorial pode ser tomado como referência pelos alunos, que
estão fazendo projectos semelhantes.Universidade da Beira Interiorinfo:eu-repo/semantics/publishedVersio
Development of pH-Sensitive magnetoliposomes containing shape anisotropic nanoparticles for potential application in combined cancer therapy
Late diagnosis and systemic toxicity associated with conventional treatments make oncological therapy significantly difficult. In this context, nanomedicine emerges as a new approach in the prevention, diagnosis and treatment of cancer. In this work, pH-sensitive solid magnetoliposomes (SMLs) were developed for controlled release of the chemotherapeutic drug doxorubicin (DOX). Shape anisotropic magnetic nanoparticles of magnesium ferrite with partial substitution by calcium (Mg0.75Ca0.25Fe2O4) were synthesized, with and without calcination, and their structural, morphological and magnetic properties were investigated. Their superparamagnetic properties were evaluated and heating capabilities proven, either by exposure to an alternating magnetic field (AMF) (magnetic hyperthermia) or by irradiation with near-infrared (NIR) light (photothermia). The Mg0.75Ca0.25Fe2O4 calcined nanoparticles were selected to integrate the SMLs, surrounded by a lipid bilayer of DOPE:Ch:CHEMS (45:45:10). DOX was encapsulated in the nanosystems with an efficiency above 98%. DOX release assays showed a much more efficient release of the drug at pH = 5 compared to the release kinetics at physiological pH. By subjecting tumor cells to DOX-loaded SMLs, cell viability was significantly reduced, confirming that they can release the encapsulated drug. These results point to the development of efficient pH-sensitive nanocarriers, suitable for a synergistic action in cancer therapy with magnetic targeting, stimulus-controlled drug delivery and dual hyperthermia (magnetic and plasmonic) therapy.This work was funded by the Portuguese Foundation for Science and Technology (FCT) within the framework of the Strategic Funding of Research Units UIDB/04650/2020 (CF-UM-UP), UIDB/00319/2020 (ALGORITMI), UIDB/04077/2020 (MEtRICs), UIDB/04436/2020 (CMEMS) and UIDB/00511/2020 (LEPABE). FCT, POCI, FEDER and NORTE2020 are acknowledged for funding through research projects PTDC/QUI-QFI/28020/2017, EXPL/EMD-EMD/0650/2021, PTDC/EEI-EEE/2846/2021 and NORTE-01-0145-FEDER-000054. MINECO (Spain) is acknowledged for project MAT2016-76824-C3-2-R. B.D.C. and V.M.C. acknowledge FCT for PhD grants SFRH/BD/141936/2018 (B.D.C.) and UI/BD/151028/2021 (V.M.C.). R.O.R. thanks FCT for contract 2020.03975.CEECIND
Red seaweeds Grateloupia turuturu and Porphyra umbilicalis as nutraceuticals and functional food: nutritional/chemical composition and immunostimulatory activity
1st Natural Products Application: health, cosmetic and food - International online conference, 4-5 February 2021The number of nutraceuticals and functional foodsfrom marine origin is increasing in the worldwide market. Specifically, the red seaweeds Grareloupia turuturu and Porphyra umbilicalis have shown their potential considering relevant bioactive compounds and nutritional value [1,2]. Nevertheless, it is pertinent to explore knowledge gaps regarding their nutritional/chemical composition and bioactivities. Hence firstly G. turuturu and P. umbilicalis proximate composition and lipid classes were determined; secondly, after preparing hydroethanolic and aqueous infusion and decoction) seaweed extracts, mycosporine-like ami no acids (MAAs) and carbohydrates were quantified. and the immunomodulatory
potential was assessed using RAW 264.7 cell line. Results show that dietary fibre was the most abundant nutritional parameter for both seaweed species, followed by relevant ash and protein contents. Free fatty acids were the main lipid class in both seaweed species, whereas tocopherols exhibited residual contentsby RP-HPLC-FLD. For hydroethanolic and aqueous extracts, several MAAs were quantified by RP-HPLC-DAD and LC-DAD ESI-MS. P. umbilicalis extracts demonstrated greater MAAs content than G. turuturu, and porphyra-334 was the main MAA. The aqueous extracts of both seaweeds showed higher carbohydrate contents than the hydroethanolic, with P. umbilicalis decoction exhibiting the highest level. Concerning the immunomodulatory activity, for 0.02 mg/mL, the exposure to P. umbilicalis aqueous extracts resulted in the most accentuated 'NO production by RAW 264.7 cells, showing immunostimulatory potential. MAAs and carbohydrates are believed to be responsible for the immunostimulatory activity [3,4]. G. turuturu and P. umbilicalis potential as functional food and nutraceuticals, relying on their relevance as sources of bioactive compounds to the food, pharmaceutical and cosmetic industries, is thus reinforcedThis work was financed by European Funds FEDER/COMPETE/POCI under project POCI-01-0145-FEDER-006958 (CITAB), and by FCT to CECAV (UIDB/CVT/00772/2020), CITAB (UlDB/04033/2020) and CESAM (UIDP/5001712020+UIDB/50017/2020). FCT is also acknowledged for a doctoral grant to Joao Ferreira (SFRH/BD/144882/2019)N
Prevalence of contagious and environmental mastitis-causing bacteria in bulk tank milk and its relationships with milking practices of dairy cattle herds in São Miguel Island (Azores)
This study aimed to assess the degree of contamination of bulk tank milk (BTM) by Staphylococcus spp. and coliform bacteria and to identify major milking practices that help perpetuate them in dairy cattle herds in São Miguel Island. In July 2014, BTM was sampled and a survey concerning local milking practices was conducted on 100 herds. Semi quantitative multiplex polymerase chain reaction detected coagulase-negative staphylococci, Escherichia coli, Staphylococcus aureus, and other coliform bacteria (Klebsiella oxytoca, Klebsiella pneumoniae, andSerratia marcescens) in 100, 75, 59, and 35 % of BTM, respectively. According to multivariable univariate models, on herds not using hot water for cleaning the milking machine and teat liners, there was at least 3.4 more odds (P<0.01) to have S. aureus or coliform bacteria contamination in BTM. The likelihoodoffinding S.aureus inBTMwas higher(P<0.001)on herds without high hygiene during milking, when milking mastitic cows at the end, on abrupt cessation of milking at dry-off, and official milk control implementation. The glove use also favored (odds ratio (OR) 5.8; P<0.01)thedetection ofcoliformbacteriainBTM.Poormilkingpracticesidentified in this study should be avoided in order to decrease S. aureus and coliform bacteria contamination of BTM. Other factors
associated with milk quality in São Miguel Island also should be further investigated
Predicting site index from climate and soil variables for cork oak (Quercus suber L.) stands in Portugal
Site productivity, assessed through site index, was modelled using partial least
squares regression as a function of soil and climatic variables. Two alternative models were
developed: a full model, considering all available explanatory variables, and a reduced
model, considering only variables that can be obtained without digging a soil pit. The
reduced model was used for mapping the site index distribution in Portugal, on the basis of
existing digital cartography available for the whole country. The developed models indicate
the importance of water availability and soil water holding capacity for site index
value distribution. Site index was related to climate, namely evaporation and frost, and soil
characteristics such as lithology, soil texture, soil depth, thickness of the A horizon and soil
classification. The variability of the estimated values within the map (9.5–16.8 m with an
average value of 13.4 m) reflects the impact of soil characteristics on the site productivity
estimation. These variables should be taken into consideration during the establishment of
new plantations of cork oak, and management of existing plantations. Results confirm the
potential distribution of cork oak in coastal regions. They also suggest the existence of a
considerable area, located both North and South of the Tagus river, where site indices
values of medium (]13;15]) to high (]15;17]) productivity classes may be expected. The
species is then expected to be able to have good productivity along the northern coastal
areas of Portugal, where presently it is not a common species but where, according to
historical records, it occurred until the middle of the sixteenth century. The present
research focused on tree growth. Cork growth and cork quality distribution needs to be
further researched through the establishment of long term experimental sites along the distribution area of cork oak, namely in the central and northern coastal areas of the
countryinfo:eu-repo/semantics/publishedVersio
Estratificação ambiental e otimização de rede de ensaios de genótipos de soja no Cerrado
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