Browsing by Issue Date, starting with "2022-03"
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- The correlation risk premium: international evidencePublication . Faria, Gonçalo; Kosowski, Robert; Wang, TianyuIn this paper we carry out a cross-country analysis of the correlation risk premium. We examine the statistical properties of the implied and realized correlation in European equity markets and relate the resulting premium to US equity market correlation risk and a global correlation risk premium. We find evidence of strong co-movement of correlation risk premiums in European and US equity markets. Our results support the existence of a strong empirical relationship between the global correlation risk premium and international equity market option returns. We document the dependence of the correlation risk premium on macroeconomic uncertainty and related variables.
- From sharks to yeasts: squalene in the development of vaccine adjuvantsPublication . Mendes, Adélia; Azevedo-Silva, João; Fernandes, João C.Squalene is a natural linear triterpene that can be found in high amounts in certain fish liver oils, especially from deep-sea sharks, and to a lesser extent in a wide variety of vegeTable oils. It is currently used for numerous vaccine and drug delivery emulsions due to its stability-enhancing properties and biocompatibility. Squalene-based vaccine adjuvants, such as MF59 (Novartis), AS03 (GlaxoSmithKline Biologicals), or AF03 (Sanofi) are included in seasonal vaccines against influenza viruses and are presently being considered for inclusion in several vaccines against SARS-CoV-2 and future pandemic threats. However, harvesting sharks for this purpose raises serious ecological concerns that the exceptional demand of the pandemic has exacerbated. In this line, the use of plants to obtain phytosqualene has been seen as a more sustainable alternative, yet the lower yields and the need for huge investments in infrastructures and equipment makes this solution economically ineffective. More recently, the enormous advances in the field of synthetic biology provided innovative approaches to make squalene production more sustainable, flexible, and cheaper by using genetically modified microbes to produce pharmaceutical-grade squalene. Here, we review the biological mechanisms by which squalene-based vaccine adjuvants boost the immune response, and further compare the existing sources of squalene and their environmental impact. We propose that genetically engineered microbes are a sustainable alternative to produce squalene at industrial scale, which are likely to become the sole source of pharmaceutical-grade squalene in the foreseeable future.
- Questionnaires measuring movement behaviours in adults and older adults: content description and measurement properties. A systematic reviewPublication . Rodrigues, Bruno; Encantado, Jorge; Carraça, Eliana; Sousa-Sá, Eduarda; Lopes, Luís; Cliff, Dylan; Mendes, Romeu; Silva, Marlene Nunes; Godinho, Cristina; Santos, RuteBackground Sleep, sedentary behaviour and physical activity are constituent parts of a 24h period and there are several questionnaires to measure these movement behaviours, the objective was to systematically review the literature on content and measurement properties of self- and proxy-reported questionnaires measuring movement behaviours in adults and older adults. Methods The databases PubMed, CINAHL, PsycINFO and SPORTDiscus were systematically searched until April 2021. Articles were included if: the questionnaires were design for adults and older adults; the sample size for validity studies had at least 50 participants; at least, both validity and test-retest reliability results of questionnaire that were developed specifically to measure the amount of sleep, sedentary behaviour or physical activity, or their combination were reported; and articles had to be written in English, Spanish, French, Portuguese, German, Italian or Chinese. Findings and conclusions Data extraction, results, studies’ quality, and risk of bias were evaluated using the Consensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines. Fifty-five articles were included in this review, describing 60 questionnaires. None of the questionnaires showed adequate criterion validity and adequate reliability, simultaneously; 68.3% showed adequate content validity. The risk of bias for criterion validity and reliability were very low in 72.2% and 23.6% of the studies, respectively. Existing questionnaires have insufficient measurement properties and frequent methodologic limitations, and none was developed considering the 24h movement behaviour paradigm. The lack of valid and reliable questionnaires assessing 24h movement behaviours in an integrated way, precludes accurate monitoring and surveillance systems of 24h movement behaviours.
- Portuguese social solidarity cooperatives between recovery and resilience in the context of COVID-19: preliminary results of the COOPVID ProjectPublication . Meira, Deolinda; Azevedo, Ana; Castro, Conceição; Tomé, Brízida; Rodrigues, Ana Cláudia; Bernardino, Susana; Martinho, Ana Luísa; Malta, Mariana Curado; Pinto, Agostinho Sousa; Coutinho, Bruno; Vasconcelos, Paulo; Fernandes, Tiago Pimenta; Bandeira, Ana Maria; Rocha, Ana Paula; Silva, Marlene; Gomes, MafaldaCovid-19 posed several challenges to all organisations in general and to social solidarity cooperatives in particular. However, the challenges faced by these cooperatives have unique features arising from their special characteristics compared to other types of cooperatives. Therefore it is vital to study these challenges and the impacts of covid-19. This study has as main goal to understand those challenges and their impact. An exploratory study was undertaken by applying 11 interviews to 11 social solidarity cooperatives. The cooperatives were chosen to be heterogeneous among the existent cooperatives in Portugal. This study corresponds to the first phase of a project that is still underway. This article presents the main results of the content analysis of the data collected from the interviews. Data show cooperatives could promptly adapt and continue their mission under pressure from the pandemic despite the first difficulties encountered in a new and unknown situation, showing a capacity to adapt and serve their members. However, these members were also submitted to several increasing and new challenges. The adaptations were possible due to legal changes in the work organisation law, from layoff to telework, government support involving financial programs, VAT, and other tax relaxation, as well as due to human resources reorganisation and the cooperatives’ staff positive attitude towards the difficulties (both leaders and general workers). Differences between the social solidarity cooperatives under study concerning digital technologies showed that those already having some infrastructure had minor adapting difficulties.
- Market-wide impact of renewables on electricity prices in AustraliaPublication . Gonçalves, Ricardo; Menezes, FlávioThis paper estimates the market-wide impact of utility-scale renewables on Australia's National Electricity Market (NEM) wholesale prices from 2009 to 2020. The goal is to understand the medium-run impact of renewable generation, as opposed to the short-run impact of weather-driven changes in renewable output. The focus is, therefore, on the relationship between renewable generation (and its growth) and wholesale prices over a long period of time. In particular, we exploit the half-hourly nature of wholesale price setting in the NEM to uncover the impact of solar and wind daily production on the distribution of prices throughout the day. In contrast to the merit-order effect literature, which focuses on the short-run (contemporaneous) impact of renewables, our results suggest that the total daily solar production has a positive, although not always significant, impact on wholesale prices throughout the day during an early development stage of solar generation. For a more recent period, following a substantive increase in utility-scale solar generation, the results are more in line with the merit-order effect literature with total daily solar production reducing wholesale prices for most of the day. This impact, however, is of several orders of magnitude lower than that predicted in the literature. We also show that the daily production of wind has a small negative impact on wholesale prices for most of the day, throughout the entire period of analysis.
- Intellectual property rights, non-market considerations and foreign R&D investmentsPublication . Albino-Pimentel, João; Dussauge, Pierre; Nayal, Omar ElPrior research has focused on how firms use a variety of organizational mechanisms to protect their R&D investments from misappropriation risks in foreign countries. Little is known, however, about how firms can rely on non-market factors to induce preferential treatment by host government authorities, thereby protecting their intellectual property overseas. In this paper, we investigate two such non-market factors, one at the country level, the other at the firm level, that are likely to influence the choice of where firms locate their innovation activities: host country inclination towards the firm's home country and the firm's political capabilities, respectively. We thus examine how IPR policies and non-market factors interact in protecting firm innovation from misappropriation and in making countries more attractive for innovation-related activities. We find support for our predictions in a sample of 1,341 foreign R&D investments made by 163 firms from 14 home countries over the period 2003–2016.
- Guia de bolso para a promoção da saúdePublication . Laverack, Glenn; Melo, PedroO Guia de Bolso para a Promoção da Saúde é um guia prático para estudantes e profissionais de saúde para a promoção da saúde. Inclui definições e exemplos práticos para planear, implementar e avaliar programas e projetos de promoção da saúde.
- Os desafios da legislação COVID‑19 à aplicação do regime da alteração das circunstâncias previsto no código civilPublication . Antunes, Henrique Sousa
- A intemporalidade e a universalidade em Bambi: eine Lebensgeschichte aus dem Walde, de Felix SaltenPublication . Cruz, Maria Amélia Gonçalves daO romance Bambi. Eine Lebensgeschichte aus dem Walde (1923), de Felix Salten, não é apenas a história fantasiosa de um jovem corço que, desde cedo, foi instruído pela mãe sobre os perigos e mistérios da floresta. Trata se, principalmente, da história do seu crescimento, na qual o fluir do tempo ocupa uma posição central, na medida em que define os ciclos da vida e determina a inevitabilidade da morte. Com o passar do tempo, o pequeno corço amadurece e cedo se apercebe de que tudo na vida é transitório. Na sua dura luta pela sobrevivência, Bambi vê no ser humano o seu principal inimigo, mas em breve descobre que ele é igualmente um ser frágil e mortal. Estes e outros aspetos – com destaque para as representações da floresta e das relações entre os seres que a habitam – conferem a este romance um carácter intemporal e universal e justificam o êxito de que ainda hoje goza a nível mundial.