In situ ion-beam-induced luminescence measurements reveal a strong enhancement of the Cr3+ emission yield in electrically conductive chromium doped β-Ga2O3 single crystals upon proton irradiation. The observed effect can be explained based on the Fermi-level pinning caused by radiation defects. This pinning of the Fermi level activates deep carrier traps that can act as sensitizers of the Cr3+ emission. In agreement with this model, in semi-insulating samples, where the Fermi level lies deep in the bandgap, the Cr3+ emission is present already in as-grown samples, and no enhancement of its intensity is observed upon proton irradiation. The boost of the Cr3+ emission yield by irradiation, observed in conductive samples, is reversed by thermal annealing in argon at temperatures above 550 °C for 30 s. The results reveal a high potential of Cr-doped β-Ga2O3 for in situ and ex situ optical radiation detection and dosimetry.

Ion-beam-induced luminescence (IBIL) measurements were performed in Cr-doped β-Ga2O3 using both protons and helium ions, showing a strong enhancement of the Cr3+ luminescence upon ion irradiation. Theoretical modelling of the IBIL intensity curves as a function of the fluence allowed estimating the effective cross-sections associated with the defect-induced IBIL enhancement and quenching processes. The results suggest that sensitizing the Cr3+ luminescence is more efficient for H+ than for He+ irradiation. Thermoluminescence (TL) studies were performed in the pristine sample, with no TL signal being observed in the spectral region corresponding to the Cr3+ emission. In agreement with the IBIL study, upon ion irradiation (with either protons or helium ions), this TL emission is activated. Moreover, it can be quenched by annealing at 923 K for 10 s, thus revealing the role played by the defects induced by the irradiation. These results show that the irradiation-induced defects play a major role in the activation of the Cr3+ luminescence, a fact that can be exploited for radiation sensing and dosimetry.

Fluctuating asymmetry (FA) represents small, random variations from the symmetric bilateral pattern, and it is a frequently used measurement of plant and animal stresses. Some studies have shown a relationship between FA and herbivory, suggesting that FA might be a reliable indicator of plant quality and plant susceptibility to herbivore attack. In this study, we investigated the relationship between leaf FA of Coccoloba cereifera Schwacke (Polygonaceae) and the pattern of attack by the scale insect Abgrallaspis cyanophylly Signoret (Hemiptera: Diaspididae). Thirty individuals of C. cereifera were marked and followed during 2007 in southeastern Brazil, and all leaves of three shoots per plant were sampled, numbered, and categorized as young, mature, or senescent. We measured right and left widths of all leaves after digitizing the images to determine levels of FA for each leaf sampled per plant. Individuals of A. cyanophylli were counted using a stereoscope in the laboratory to determine infestation levels. Leaves of C. cereifera exhibited true patterns of FA, as shown by the normal distribution of asymmetry values. We observed high variation in attack rates by A. cyanophylly among C. cereifera individuals, with 43.3% of plants with no insects, whereas others exhibited up to 23,000 insects. No statistically significant relationship was observed between variation in FA and variation in A. cyanophylli among plants. These results suggest that FA cannot be used as an indicator of plant quality and susceptibility to herbivore attack but suggest that herbivores themselves might act as plant stressors.

Several phenotypic differences observed in Parkinson’s disease (PD) patients have been linked to age at onset (AAO). We endeavoured to find out whether these differences are due to the ageing process itself by using a combined dataset of idiopathic PD (n = 430) and healthy controls (HC; n = 556) excluding carriers of known PD-linked genetic mutations in both groups. We found several significant effects of AAO on motor and non-motor symptoms in PD, but when comparing the effects of age on these symptoms with HC (using age at assessment, AAA), only positive associations of AAA with burden of motor symptoms and cognitive impairment were significantly different between PD vs HC. Furthermore, we explored a potential effect of polygenic risk score (PRS) on clinical phenotype and identified a significant inverse correlation of AAO and PRS in PD. No significant association between PRS and severity of clinical symptoms was found. We conclude that the observed non-motor phenotypic differences in PD based on AAO are largely driven by the ageing process itself and not by a specific profile of neurodegeneration linked to AAO in the idiopathic PD patients.

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As dificuldades económicas têm levado a União Europeia a adotar novas estratégias de competitividade, como o caso da denominada “Estratégia Europeia 2020” (CE, 1997; 1997a; 1998; 2010). Esta estratégia alargou-se à política fiscal de vários estadosmembros, através da qual eles têm vindo a adotar soluções fiscais inovadoras para aumentar o investimento e a sua competitividade, como é o caso dos regimes de tributação dos residentes não habituais (Catarino, 2016). Nesta pesquisa avaliamos a evolução do conceito de residência no imposto de renda das pessoas físicas como forma de atrair residentes qualificados e investimento.Sistematizámos o regime dos residentes não habituais comparando das características entre Portugal e Espanha, e visámos determinar se os seus regimes de tributação são realmente mais atrativos do que o regime geral e, em caso afirmativo, em que termos. Apurámosa existência de diferenças que possam influenciar a opção entre um ou outro por parte dos interessados. Concluímos que não há uma evolução no conceito de residência adotado, que a maior atratividade do referido regime se efetiva, através da aplicação das alíquotas de imposto de renda das pessoas físicas mais baixas e que a sua semelhança não permite concluir pela supremacia de um regime face ao outro.

With the emergence of social media and continuous progress and paradigm-shifting breakthroughs in new media, communication professionals need to keep up to date with what consumers are talking about online. Brands tapped into this reality and understood that to influence interactions in this digital landscape, they would need to bring digital influencers into the equation about social media. By recognising that partnerships between beauty brands and digital influencers are a marketing strategy increasingly used by brands and by resorting to Instagram as a research environment, the project presented in this article aimed to understand, through a case study, the impacts that partnerships between the beauty brand Freshly Cosmetics and several digital influencers may have on its followers in Portugal. The study was conducted during the development of a master's dissertation in Applied Communication and, despite focusing on a single brand, enabled the authors to outline the methodology that will be further explored in future work with larger samples of brands. Ten publications from different digital influencers were selected and analysed according to a set of criteria, and a focus group was conducted with ten women who knew the brand under analysis. According to the results obtained, although digital influencers have some impact on decision-making, the participants preferred brands they already knew and their opinions were formed based on research and not on digital influencers' statements. For the participants, feedback from real consumers, external research conducted on their own, and the opinions of experts in the field are responsible for the brand's image in the eye of the consumer.