Browsing by Issue Date, starting with "2020-08"
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- Challenges in teaching organic chemistry remotelyPublication . Crucho, Carina; Avó, João; Diniz, Ana Marta; Gomes, MárioThe coronavirus disease (COVID-19) pandemic has changed not only people’s daily lives but also the education system. The rise of e-learning all across the world has challenged both students and teachers to adapt to digital technologies and a novel learning experience on both sides. As if COVID-19 was not enough, many students were facing the alien territory of organic chemistry for the first time. There is no denying that organic chemistry is a tough subject, and several students may also have preconceived misconceptions. In addition, organic chemistry can be challenging to teach remotely. It is very abstract in nature; it involves many concepts, and the teacher typically uses molecular models of one kind or another to depict molecules in three dimensions. Nonetheless, challenges provide an opportunity to implement new strategies to increase students’ interest, motivation, and understanding. However, most educators only had a few days to put everything they do in class onto an online platform. In this study, we evaluated the effect of these changes in the teaching and learning of organic chemistry at a first-year undergraduate level. Our results show that student success depends on the digital resources used for the different subjects. Students that received weekly quizzes performed better than those who did not, and a positive correlation exists between quiz scores and final exam marks. Based on the student's feedback, the implementation of quizzes was a successful didactic tool that helped them review the topics. In addition, the incorporation of open-access web-based tools led to a dynamic online classroom experience.
- Wind power with energy storage arbitrage in day-ahead market by a stochastic MILP approachPublication . Gomes, Isaías; Melício, R.; Mendes, Victor; Pousinho, H. M. I.This paper is about a support information management system for a wind power (WP) producer having an energy storage system (ESS) and participating in a day-ahead electricity market. Energy storage can play not only a leading role in mitigation of the effect of uncertainty faced by a WP producer, but also allow for conversion of wind energy into electric energy to be stored and then released at favourable hours. This storage provides capability for arbitrage, allowing an increase on profit of a WP producer, but must be supported by a convenient problem formulation. The formulation proposed for the support information management system is based on an approach of stochasticity written as a mixed integer linear programming problem. WP and market prices are considered as stochastic processes represented by a set of scenarios. The charging/discharging of the ESS are considered dependent on scenarios of market prices and on scenarios of WP. The effectiveness of the proposed formulation is tested by comparison of case studies using data from the Iberian Electricity Market. The comparison is in favour of the proposed consideration of stochasticity.
- Biomonitoring as an underused exposure assessment tool in occupational safety and health context: challenges and way forwardPublication . Viegas, Susana; Jeddi, Maryam Zare; Hopf, Nancy B.; Bessems, Jos; Palmen, Nicole; Galea, Karen S.; Jones, Kate; Kujath, Peter; Duca, Radu-Corneliu; Verhagen, Hans; Santonen, Tiina; Pasanen-Kase, RobertRecent advances in analytical chemistry have allowed a greater possibility of using quantitative approaches for measuring human exposure to chemicals. One of these approaches is biomonitoring (BM), which provides unequivocal evidence that both exposure and uptake of a chemical have taken place. BM has been a longstanding practice in occupational health for several reasons. BM integrates exposure from all routes. It can help identify unintentional and unexpected exposures and assess the effectiveness of existing risk-management measures. BM also provides relevant information to support policy development by delivering better evidence of workers' exposure to chemical substances, even within the framework of the present regulations. Thus, BM can allow for both the evaluation of the impact of regulation and the identification of further needs for new or improved regulation. However, despite all these well-recognized advantages, BM is currently an underused exposure assessment tool. This paper provides an overview of the key aspects to be considered when using BM in the context of occupational health interventions. Additionally, this paper describes the potential of BM as an exposure assessment tool, distinguishing the role of BM in exposure assessment and health surveillance and clarifies ethical and communication aspects to guarantee that general data protection regulations are followed. In addition, actions and research needs are identified (particularly with reference to the European situation), which aim to encourage the increased use of BM as an exposure assessment tool.
- Positive-definiteness and integral representations for special functionsPublication . Buescu, Jorge; Paixão, AntónioIt is known that a holomorphic positive definite function f defined on a horizontal strip of the complex plane may be characterized as the Fourier-Laplace transform of a unique exponentially finite measure on R. In this paper we apply this complex integral representation to specific families of special functions, including the Gamma, zeta and Bessel functions, and construct explicitly the corresponding measures, thus providing new insight into the nature of complex positive and co-positive definite functions. In the case of the zeta function this process leads to a new proof of an integral representation on the critical strip.
- Cytotoxic effect of filtering respiratory protective devices from the waste sorting industry: is in vitro toxicology useful for risk characterization?Publication . Viegas, Carla; Twarużek, Magdalena; Dias, Marta; Almeida, Beatriz; Carolino, Elisabete; Soszczyńska, Ewelina; Ałtyn, Iwona; Viegas, Susana; Caetano, Liliana AranhaThe use of Filtering Respiratory Protective Devices (FRPD) is mandatory in Portugal to protect workers from the waste industry of harmful exposures. Deleterious health effects of exposure to bioburden via inhalation and/or ingestion include respiratory symptoms and nephrotoxicity. Between January and February 2019, 118 FRPD samples were collected in one waste sorting industry and characterized regarding microbial contamination and cytotoxicity, defined as cell metabolic activity, through the MTT colorimetric assay (3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide). Cytotoxic effect was classified according to the percentage of extinction values with respect to the control group, as follows: absent (≥90); low (80% to 90%, +); medium (60% to 79%, ++); and high (below 60%, +++). For 113 samples the MTT assay revealed a cytotoxic effect in A549 cells, of which 81 presented high cytotoxicity. In SK cells, a cytotoxic effect was observed in 56 samples, of which five displayed a high cytotoxic effect. Several moderate (p<0.05) to strong (p<0.01) correlations were found between higher bacterial and fungal counts both in interior layers (fungi and bacteria) and in exhalation valves (fungi) of FRPD samples and reduced cellular metabolic activity of SK cells. On the basis of the obtained results for the cytotoxic effect of FRPD samples on two different cells lines, it was determined that A549 cells exhibited a cytotoxic effect for a higher number of FRPD, whereas the SK cells model correlated better with the other assessed parameters, namely, bacterial and fungal load and conditions of FRPD use. Although the results are not conclusive on the most appropriate cell line to assess FRPD cytotoxicity, they reinforce the importance of in vitro toxicology in exposure assessments to determine the cytotoxicity of mixtures of contaminants, for better risk characterization and selection of appropriate risk management measures.
- Problemas, escalas e crítica na história da ediçãoPublication . Medeiros, NunoCMPH e o Observatório da História convidam para uma conversa Nuno Medeiros, do Instituto Politécnico de Lisboa e Universidade de Lisboa, e Maria Rita de Almeida Toledo, da EFLCH-UNIFESP [palestra online].
- Exploring pharmacists’ orientation towards patients in Portuguese community pharmaciesPublication . Cavaco, Afonso Miguel; Grilo, Ana; Barros, LuisaBackground: Patient-centered care has been associated with improved patient outcomes and healthcare satisfaction. The present study aimed to explore pharmacy practitioners’ orientation to patients in daily work, as well as job satisfaction as a possible associated factor. Methods: A cross-sectional survey of a sample of Portuguese community pharmacists was used for gathering participants’ demographics, professional and work-related data, self-perceived level of technical and relational competencies, and the importance ascribed to these skills. The Portuguese version of the Patient-Practitioner Orientation Scale (PPOS) and a Portuguese-reduced version of a Healthcare Job Satisfaction Scale completed the online questionnaire. Results: A sample of 274 respondents comprised 81.1% females, with a mean age of 37.2 years, 11.6 years of work experience on average, and subject to a work intensity of 5.36 clients per hour, mainly for counter dispensing (73.0%). Overall, technical competencies were significantly more important than relational ones, but practitioners with fewer experiences self-perceived as weaker in communication competencies. Females scored higher in relational competencies importance as well as in PPOS (p < 0.05). No significant difference in PPOS was found between pharmacists with more and less direct interaction with patients, but higher when performing consultation services (p < 0.05). Conclusions: The existing orientation to patients seems to be under the desired levels and independent of community pharmacists’ work intensity, nevertheless linked with work experience and differentiated patient services. Although professionals might recognize the importance of relational competencies to provide patient-centered care and achieve better outcomes, it is essential to promote clinical training amongst community pharmacists.
- Developing an entrepreneurial mindset among engineering students: encouraging entrepreneurship into engineering educationPublication . João, Isabel; Silva, JoãoIt is unquestionable the role of entrepreneurship as a driver of innovation and economic development. The world is dynamically changing and intensively interconnected carrying new challenges and opportunities to the new generation of engineers working in a world where innovation will continue to evolve very quickly. This paper addresses the need to train engineering students to be entrepreneurial engineers considering the global challenges and the role that higher education institutions should play in developing an entrepreneurial mindset among engineering students. The paper presents and discusses the results of a survey carried out in a Portuguese engineering school with the goal of investigate students' entrepreneurial mindsets. The main objective is to understand the extent by which entrepreneurship is addressed in students' engineering programs as well as students' perceptions of their entrepreneurial related skills and the reasons that would lead the students to start or not start a business as well as their perception of the ability to immediately start a business. The results of the study are critically analysed in light of the challenges and opportunities facing future engineers. The work, although limited to a specific context is a valuable starting point for additional research and for the implementation of faculty strategies to improve entrepreneurship education.
- A valsa lenta da pandemia no salão da academia: o mundo em suspenso, o deslaçamento como risco e a persistência como mantraPublication . Medeiros, Nuno[palestra online]
- Occupational exposure to mycotoxins: different sampling strategies telling a common story regarding occupational studies performed in Portugal (2012–2020)Publication . Viegas, Susana; Viegas, Carla; Martins, Carla; Assunção, RicardoIn occupational settings where exposure to organic dust occurs (e.g., intensive animal production, waste management, farming, and many others) workers can also be exposed to mycotoxins. However, recognizing exposure to mycotoxins in workplace environments does not happen commonly and, consequently, remains as a not identified occupational risk factor. In the last decade, work developed in different occupational settings, using different sampling approaches reported that occupational exposure to mycotoxins occurs and it's of upmost importance to be seen as an occupational concern that needs to be tackled. This paper intends to discuss the several possibilities available for assessing and characterizing the occupational exposure to mycotoxins through the description of the advantages and limitations of the different sampling strategies. Overviewing the approaches and the main achievements used in several field campaigns developed in Portugal, the knowledge obtained will be used to support the identification of the main aspects to consider when designing new occupational studies. The need for additional research work will also be discussed where new directions to follow will be debated.