The diversification benefits of investing in Bitcoin

In this dissertation we aim to study the diversification benefits of investing in Bitcoin in a context of a well-diversified, balanced portfolio constituted by bonds and stocks (classic 60% equity/40% bonds Traditional Portfolio). Based on historical data, we evaluate the impact of different (i) holding periods of the investment, (ii) rebalancing frequencies of the portfolio and (iii) range of bitcoin allocations, on the overall performance of a given portfolio. A rolling analysis was performed to capture the time-dependent dynamics between these assets. We conclude that, for the sample period under analysis, quarterly rebalanced bitcoin allocations between 0.5%-7.5% for a minimum holding period of 3 years have always been beneficial for the investor, regardless of the period in which the investment was made. Although past performance is no guarantee of future performance, we believe that the empirical conclusions presented in this dissertation have significant implications for institutional investors.Nesta dissertação pretendemos estudar os benefícios de investir em Bitcoin no contexto de um portefólio diversificado de ações e obrigações (portfólio clássico 60% ações/40% obrigações). Com base numa análise histórica, avaliámos o impacto de diferentes: (i) períodos de investimento, (ii) frequências de rebalanceamento e (iii) intervalos de alocação de bitcoin na performance global de um dado portfólio. Uma rolling analysis foi executada a fim de capturar as dinâmicas temporais entre estes ativos. Concluímos que, no período amostral em análise, rebalanceamentos trimestrais de alocações em Bitcoin entre 0.5%-7.5% num período mínimo de 3 anos foram sempre vantajosas para o investidor, independentemente do período em que o capital foi aplicado. Apesar de performance passada não ser garantia de performance futura, acreditámos que as conclusões empíricas desta dissertação têm importantes implicações para investidores institucionais

First approach to the analytical characterization of barrel-aged grape marc distillates using phenolic compounds and colour parameters

Phenolic compounds (benzoic and cinnamic acid derivatives) were determined by high-performance liquid chromatography with multiple wavelength detector (HPLC--MWD) in grape marc distillates aged in Quercus petraea, Quercus robur and Quercus alba wooden barrels. In addition to colour indices and evaluable polyphenols, all samples were described by sensorial analysis. There were significant differences in the mean concentrations of the majority of phenolic compounds among the samples. Gallic and benzoic acids were the most abundant and samples aged in Q. robur from Galicia (NW of Spain) had the highest concentration of most of the determined phenols. Grape marc distillates aged in Q. robur obtained the highest values of all sensorial attributes, whereas samples aged in Q. petraea and Q. alba obtained similar scores. Principal component analysis accounted for 88.32 % of total variance, showing a good separation of aged distillates in terms of phenolic compounds and colour characteristics, according to the species and origin of the oak wood used in the ageing process.We are grateful for the financial support of this work to the Spanish Ministry of Science and Innovation (project CTQ2011-28967), and partial financial support from the FEDER funds of the European Union and to the Regulatory Board of Geographical Names of the Traditional Galician Spirits and Liqueurs for providing the samples. Jose Manuel Salgado is grateful for postdoctoral fellowship (EX-2010-0402) of Education Ministry of Spanish Government

Optimization of initial moisture and temperature in solid-state fermentation to produce cellulases by Aspergillus uvarum on olive mill and winery wastes

Wineries and olive oil industries are dominant agro-industrial activities in southern European regions. The use of byproducts of these industries could reduce the costs of enzymes production. Olive pomace, exhausted grape marc, vineshoot trimmings are lignocellulosic materials, thus they have potential to be used as substrate for cellulase production by solid-state fermentation. Since, moisture and temperature are important parameters on SSF, a full factorial design was planned to optimize these parameters. Optimum conditions were 29 ºC and 75% of moisture, and 33.49 U/g of cellulose activity were achieved

Cellulase and xylanase production by A. uvarum in solid-state fementation using a packed-bed bioreactor

Wastes from olive oil and wine industries (as exhausted grape mark, vineshoot trimmings, olive pomace and vinasses) were used as substrate for lignocellulolytic enzymes production (as endocellulases, endoxylanase) by solid state fermentation in a packed-bed bioreactor. In previous works, A. uvarum was selected as suitable fungus to produce cellulases and xylanases, also composition of substrate, temperature and moisture content were optimized. An important parameter in packed-bed bioreactors is air flow rate, thus its effect on enzymes production was studied. The highest enzyme production was obtained for the lower aeration rate (0.2 L/min). It was observed that increasing air flow the enzyme production was lower

L’Educació Física a l’educació primària (LOCE). Un retorn a la perspectiva tradicionalista, psicomotricista i higiènica de l’EF?

L’actualitat educativa es troba immergida en aquests moments i dintre de l’àmbit de l’ensenyament no universitari, en els canvis derivats de la promulgació de la Llei Orgànica de Qualitat de l’Educació (coneguda ja com a LOCE, i promulgada el 23 de desembre del 2002). En aquest treball presentem una anàlisi crítica de les modificacions del currículum oficial d’Educació Física per a l’etapa educativa de l’Educació Primària. Després de l’anàlisi dels elements bàsics del currículum presentats en aquests documents (objectius, continguts i criteris d’avaluació), podem derivar, com a conclusió principal, que el nou currículum sembla centrar-se més en una tornada a un enfocament dins la “perspectiva tradicionalista” dintre de la Teoria Curricular (Kirk, 1990, pàgs. 37-39 i Contreras Jordán, 1998, pàg. 47), en la qual es veu el professor com a executor de quelcom dissenyat per agents externs a l’acte educatiu en si, en clara confrontació amb les aportacions de la llei d’educació anterior, la LOGSE

Extraction of ferulic acid from agro-industrial wastes and evaluation of bioconversion of ferulic acid to vanillin by Streptomyces setonii

Several agro-industrial wastes (as chestnut and pistachio shells, grass, leaf fruit, vine leaf,and, red and white grape stems) were evaluated to ferulic acid extraction. The chemical analysis of these raw materials shows a high content of xylan in pistachio shells (33%), following the biorefinery concept, this fraction can be used in xylitol manufacture. The lignocellulosic materials were submitted to an alkaline extraction to obtain phenolic compounds, reaching a concentration of 312 mg ferulic acid/L in grass wastes. Other phenolic compounds were also extracted (gallic acid, p-coumaric acid, syringic acid etc.) depending of used raw material. Besides, the ferulic fermentation into vanillin was assayed. The higher concentration of vainillin (2692 mg/L) was achieved at 27 h (QP = 99.704 mg/L·h and YP/S = 0.50 mg/mg) using Streptomyces setonii

Enhancing antioxidants extraction from agro-industrial by-products by enzymatic treatment

Nowadays, agro-industrial by-products are of increasing interest as a source of antioxidant compounds. Thus, alternative green techniques to extract antioxidant compounds have been pursued. The use of enzymes to release bioactive compounds through antioxidant activity reduces the environmental impact caused by traditional extraction systems using organic solvents. A crude enzymatic extract containing carbohydrolases was produced by solid-state fermentation (SSF) of an olive pomace and brewery spent-grain combination. The crude extract was evaluated at different temperatures and pH values and its thermostability was studied. Results showed that β-glucosidase and cellulase were more stable than xylanase, particularly cellulase, which kept 91% of its activity for 72 h at 45 °C. The extract was also applied in enzymatic treatments (ET) to liberate antioxidant compounds from winery, olive mill and brewery by-products under optimal conditions for enzymatic activities. The highest antioxidant activity was found in extracts obtained after enzymatic treatment of exhausted olive pomace (EOP). Enzymatic crude extract produced by SSF was successfully applied in the extraction of antioxidant compounds from winery, olive mill and brewery by-products. Thus, integrating SSF and enzymatic technologies is a valuable approach to implement circular economy practices in the agro-food industry.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTec-Norte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte. This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of SFRH/BD/114777/2016.info:eu-repo/semantics/publishedVersio

Importance of gender in students demand for higher education in tourism: The case study of a tourism and hospitality higher education institution

The importance of the scientific area of tourism, particularly in higher education, requires an analysis and interpretation of its evolution in Portugal. Assuming the widespread recognition of tourism and leisure transversal influence in the contemporary society, one considers the need for rigorous studies on the implications of gender issues in knowledge production in higher education institutions (HEI). Therefore, this study intends to understand the trends in students’ demand for a degree in the tourism field and the importance of gender in higher education, and also their implication in the tourism sector labour market. This study is aimed mainly at interpreting the concern to understand the need and importance of studies on gender issues in tourism higher education, from different perspectives. To determine that the image of an HEI and the students’ demand for this field of study may rely on a policy and strategy that include these relevant gender issues, both in an educational and in an employment perspective, which is also a purpose of this study. In the tourism sector, according to Costa, Carvalho and Breda (2011, p. 39), the Portuguese reality is vertically segregated and, despite being a feminised sector, men occupy most top-level positions. Moreover, tourism workers, particularly female workers, are in general subject to poorer conditions of employment, such as low-pay, long working hours and more precarious contracts. The data [collected by these authors] hint at a very wide gender pay gap in the tourism industry. Costa, Carvalho, Caçador and Breda (2012, p. 70) also analysed the higher education and the labour market in the tourism sector and concluded that although women prevail among tourism graduates in Portugal, men earn higher salaries and fill most top-level positions in the tourism sector. [Their] study diagnose[d] disparities between male and female tourism graduates in the following domains: areas of activity, positions, and salary