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Risk without borders: a transfer entropy analysis of geopolitical spillovers in low- and lower-middle-income markets
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How geopolitical risk affects stock markets in low and lower-middle-income countries remains
an area often overlooked. This study analyzes daily data from 2014 to 2025 for 16 stock
markets and two geopolitical risk subindices, acts and threats. The transfer entropy is applied
in a dynamic framework to measure asymmetric and time-varying information flows. The
findings reveal a heterogeneous influence of acts and threats, varying by country-income level,
geographic region, and over time, and suggest an increased sensitivity of financial markets
after 2020, particularly in response to acts rather than threats. This highlights distinct
geopolitical risk transmission, requiring tailored investment strategies and policy response
Tracking oil price shocks and airline stock reactions using entropy-based approaches
Get PDFThe relationship between oil prices and the airline industry is economically important yet empirically complex, presenting significant challenges, with prior research yielding conflicting evidence on the nature, strength, and direction of their interaction. This study contributes to the literature moving beyond traditional linear assumptions, applying Shannon and Rényi transfer entropy to evaluate the nonlinear and state-dependent information flow between oil, oil volatility, and six international airline indices. The empirical findings reveal a significant but heterogeneous information flow between West Texas Intermediate (WTI) and airline indices, suggesting a relationship of mutual influence, where the directional information flow from WTI to airline indices consistently surpasses the reverse flow. In the case of the Crude Oil Volatility Index (OVX), results show a dominant flow of information from each airline index to the OVX index, indicating that sector-specific shocks can shape market expectations of oil volatility. The Rényi entropy analysis further uncovers tail-driven dynamics: at low orders of Rényi entropy, the entropy values remained predominantly negative between WTI and airline indices, while they remained predominantly positive, particularly from OVX to airline indices. However, at very high orders of entropy, there is a more traditional flow of information from WTI to airline indices. These findings enable policymakers to develop more effective, targeted, and economically sound energy policies for the transportation sector and the wider economy
Considerações Finais
No full textEste capítulo corresponde às Considerações Finais da obra Diálogos sobre Educação e Tecnologias Digitais. Fundamentos, Dilemas e Desafios. Esta obra, organizada por Elisabete Cruz e Ângela Balça, e editada pelo Centro de Investigação em Educação e Psicologia da Universidade de Évora nasce da convicção de que a educação e as tecnologias digitais constituem, hoje, uma das interseções mais críticas e desafiantes do pensamento contemporâneo. Vivemos um tempo em que a aceleração tecnológica ultrapassa largamente a capacidade humana de reflexão e, por tal, pensar criticamente o digital tornou-se uma urgência ética, cultural e pedagógica.
É neste cenário de urgência e de necessidade de diálogo informado que se construiu este volume, estruturado a partir de um Ciclo de Conferências, promovido no âmbito da unidade curricular, da responsabilidade científica de Elisabete Cruz, “Educação e Tecnologias Digitais”, inserida no Programa de Doutoramento em Ciências da Educação da Universidade de Évora
SINDICALISMO NO ENSINO SUPERIOR E NA INVESTIGAÇÃO . JOÃO CUNHA SERRA . UMA VIDA EM LUTA
No full textEste livro trata da história do sindicalismo no Ensino Superior e Investigação em Portugal
desde a revolução de Abril de 1974 até aos
dias de hoje. O seu eixo condutor é o percurso de luta do sindicalista João Cunha Serra.
Ao longo de quatro décadas, Cunha Serra
esteve envolvido nos principais momentos de
negociação, reivindicação e luta, no quadro da sua atividade no Sindicato dos Professores da Grande Lisboa e na FENPROF. A presente obra reúne mais de meia centena de testemunhos de amigos, camaradas e companheiros.
Contém, ainda, dois estudos sobre a história
sindical, realizados, respetivamente, por
Manuel Carlos Silva, e por João Pedro Santos e José Nuno Matos. Este é um livro fundamental para compreender o sindicalismo português e uma das suas principais figuras
Mucocelo biliar em cães
No full textEste relatório de estágio está dividido em três partes. A primeira parte contém uma análise descritiva e estatística da casuística observada pela autora durante o seu estágio de seis meses no Anicura Atlântico Hospital Veterinário. A segunda parte inclui uma monografia sobre o tema “Mucocelo Biliar em Cães”, em que é feita uma revisão bibliográfica sobre o tema. Na última parte é apresentado e discutido um caso clínico relacionado com o tema da monografia.
O mucocelo biliar em cães é uma afeção resultante da sobreprodução de muco pelo epitélio da vesícula biliar, causando frequentemente doença biliar extra-hepática em animais de porte pequeno a médio e de idade média a avançada. O seu diagnóstico tem sido crescente, embora a sua etiologia não esteja totalmente compreendida. Têm sido identificados fatores relacionados com a formação de mucocelo, como endocrinopatias e predisposições genéticas. O tratamento de eleição é a colecistectomia; Gallbladder Mucocele in Dogs - Abstract: This report is divided in three components. The first one entails a descriptive and statistical analysis of the set of cases followed by the author during her six-month internship in Anicura Atlântico Hospital Veterinário. The following part includes a bibliographic review on the subject “Gallbladder Mucocele in Dogs”. To conclude the report, a clinical case related to the theme of the review is presented and discussed.
Gallbladder mucocele is a disorder resulting from the overproduction of mucus by the gallbladder epithelium, often causing extrahepatic biliary disease in small to medium sized and older dogs. Its diagnosis has become more common, although the etiology is not fully understood. Several agents have been associated with the development of gallbladder mucocele, such as endocrinopathies and genetic factors. The gold standard course of treatment is cholecystectomy
Nemátodes gastrointestinais em cães de canil no médio Tejo - estudo prospetivo
No full textNemátodes gastrointestinais em cães de canil no Médio Tejo- estudo prospetivo
Nemátodes gastrointestinais apresentam elevada relevância mundial devido à sua
ampla distribuição e potencial zoonótico, constituindo um risco para a saúde pública,
especialmente animais alojados em canis. Este estudo teve como objetivo identificar os
nemátodes gastrointestinais mais prevalentes na região do Médio Tejo. Para tal,
recolheram-se em março de 2025, 25 amostras de fezes provenientes de quatro canis na
região de estudo, analisadas pelo método de flutuação de Willis com solução saturada de
sulfato de zinco. A prevalência global obtida foi de 15% (3,43%-23,28%). Os
ancilostomatídeos foram os mais prevalentes, com uma prevalência de 7% (3,43%-
12,48%), seguindo-se Toxocara canis com 6% (2,78%-5,45%), Trichuris vulpis com 1%
(0,18%–5,45%) e coinfeções por ancilostomatídeos e T. canis com 1% (0,18%-5,45%).
Dado o carácter zoonótico dos agentes identificados, é essencial implementar medidas
adequadas para prevenir a transmissão a humanos e a perpetuação dos ciclos biológicos; Gastrointestinal nematodes in kennel dogs in the Médio Tejo region- prospective
study - Abstract: Gastrointestinal nematodes hold significant global relevance due to their wide
distribution and zoonotic potential, representing a public health risk, particularly dogs
housed in kennels. This study aimed to identify the most prevalent gastrointestinal
nematodes in the Médio Tejo region. For this purpose, 25 fecal samples were collected in
March 2025 from four kennels within the study area and analysed using the Willis
flotation method with zinc sulfate saturated solution. The overall prevalence obtained was
15% (3,43%-23,28%). Ancylostomatidae were the most prevalent, with 7% (3,43%-
12,48%), followed by Toxocara canis with 6% (2,78%-5,45%), Trichuris vulpis with 1%
(0,18%-5,45%), and co-infections of Ancylostomatidae and T. canis with 1% (0,18%-
5,45%). Given the zoonotic nature of the identified agents, implementing appropriate
measures is essential to prevent transmission to humans and the perpetuation of their
biological cycles
Characterization of Roman painted frescoes from Mecenate's Auditorium and from Città Dipinta - Traianus's Thermae for their preventive conservation
No full textCharacterization of Roman Painted Frescoes from Mecenate's Auditorium and from Città Dipinta - Traianus's Thermae for their Preventive Conservation - ABSTRACT: This master thesis is focusing on the archaeometric investigation and analysis of Roman Painted Frescoes from Mecenate's Auditorium and from Città Dipinta - Traianus's Thermae, to characterize the materials used in execution of the painting layers and mortar, for their Preventive Conservation.
Mecenate's Auditorium and Città Dipinta fresco paintings are unique with their decorations which characterized by absence of the human figures and focusing on nature and topographical drawings. Both of them are located in archaeological imperial buildings in Rome. The main objective of this study was to characterize the fresco wall paintings through studying the painting techniques, the pigments used in execution of paintings, mortars characteristics at Citta Dipinta which will play role in the preliminary dating of the wall. Furthermore, determine the conservation condition and the previous conservation procedures that may severely affect the paintings in the future.
Selected analytical and investigation techniques have been used for this purpose such as Optical – Stereo microscopy, Micro Raman Spectroscopy and Thermogravimetric analysis. According to the acquired data and its interpretation, a variety of pigments has been identified representing the color palette of Roman fresco paintings such as, Red Ochre, Cinnabar, Yellow Ochre and Carbon black; regarding the blue pigment it was challenging to be confirmed. For the mortars it was really unique with high strength and durability attributed to its hydraulic characteristics. A degradation product has been detected such as Gypsum on the surface of paint layers at the Auditorium, and layer of yellowish Paraloid acrylic resin was found and this is used in previous conservation.
The results of the archaeometric study and the documentation of the degradation aspects at the Auditorium of Mecenate and Citta Dipinta paintings, enabled to propose a preventive conservation plan, to prevent the sites from more alteration and degradation and establish maintenance system for the future
Dynamic Cross-Correlation Between BRICS Markets, Commodities and Green Bonds
No full textThis paper evaluated the cross-correlation between the BRICS (Brazil, Russia, India, China and South Africa) markets with commodities and green bonds. For this purpose, the detrended moving-average cross-correlation coefficient (?DMCA) was used, based on a sliding windows approach, with data covering a sample before the COVID-19 pandemic, during the COVID-19 pandemic and after Russia invaded Ukraine. The results show a positive cross-correlation between BRICS markets and commodities and green bonds after the COVID-19 pandemic, mainly for long time scales. This result can contribute to financial risk analysis, especially regarding hedge funds
Coupling homogeneous chains of damped harmonic oscillators
No full textWe study vibrational properties of nonhomogeneous materials. We consider idealized materials composed of one dimensional chains of damped harmonic oscillators represented by a sequence of particles, springs and dampers. The system is linear, thus possesses exact explicit solutions, nevertheless the formulas can be very complicated. Homogeneous chains are used as basic building blocks for characterizing global dynamics of the system. In particular, we determine the solutions for a system composed of two distinct homogeneous chains in terms of the original solutions for these two homogeneous chains, and the original parameters, when uncoupled. Two types of coupling are considered, one with a gluing particle, the other with a gluing spring and damper
Enhancing the sustainability of growing media: exploring pine bark as a perlite substitute in coir-based substrates for lettuce cultivation.
Get PDFIncreasing the sustainability of growing media constituents is a priority nowadays. This study aimed to evaluate whether pine bark can replace perlite in coir-
based substrates. For this purpose, an experiment was carried out with four treatments: two coir-based mixes, one containing perlite and the other pine bark,
and two electrical conductivities of nutrient solution (1.5±0.2 and 2.5±0.2 dS m-1). Lettuce plants (Lactuca sativa L. ‘Godzilla’) were grown in styrofoam boxes
filled with growing media containing, by volume, 80% coir, 12% compost, and 8% of either perlite or pine bark. The pine bark led to an increase in the electrical
conductivity and bulk density of the mix. The presence of pine bark in the mix did not influence the effect of nutrient solution concentration on the average
values of pH and electrical conductivity of the leachate. The electrical conductivity of leachate increased with the nutrient solution ion concentration. The
presence of pine bark in the mix did not affect the shoot nutrient content of N, P, K, Ca, and Mg. Shoot iron and boron content were higher in plants grown with
pine bark-containing substrates. Shoot N and P increased with a nutrient ion concentration. The presence of pine bark relative to perlite did not affect the
influence of nutrient solution concentration on photosynthetic pigment contents, shoot dry weight, or yield (head fresh weight). This indicates the potential of
pine bark as a sustainable alternative to perlite without compromising lettuce production