Browsing by Issue Date, starting with "2017-10"
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- A Peregrinação de Fernão Mendes Pinto e os limites da interpretaçãoPublication . Carvalho, João Carlos Firmino Andrade deTerminada a peregrinação aventurosa de Fernão Mendes Pinto (decorrida entre 1537 e 1558), começou (entre 1569/70 e 1578/80) a escrita da aventura e da peregrinação dos sentidos e significações no interior da própria narrativa autobiográfica romanceada, enunciada, na perspectiva de Stegagno Picchio(1), na primeira pessoa do anti-herói-indivíduo. Todavia, depois dessa segunda aventura/peregrinação (a da escrita) começou ainda uma terceira: a da leitura- -recepção-interpretação, quer mesmo antes da sua publicação, quer, sobretudo, a partir de 1614(2). De facto, o problema da veracidade da extraordinária peregrinação vertida na narrativa coloca-se logo no século XVII e a sua discussão prolonga-se pelos séculos XVIII e XIX, tornando-se aporética com a visão que insiste em lê-la como narrativa documental e, simultaneamente, descrê da sua credibilidade enquanto tal.
- Ultrasensitive gold micro-structured electrodes enabling the detection of extra-cellular long-lasting potentials in astrocytes populationsPublication . Mestre, Ana L. G.; Cerquido, Monica; INÁCIO, PEDRO; Asgarifar, Sanaz; Lourenco, Ana S.; Lurdes S. Cristiano, M.; Aguiar, Paulo; Medeiros, Maria C. R.; Araújo, Inês; Ventura, Joao; Gomes, Henrique L.Ultra-sensitive electrodes for extracellular recordings were fabricated and electrically characterized. A signal detection limit defined by a noise level of 0.3-0.4 mu V for a bandwidth of 12.5 Hz was achieved. To obtain this high sensitivity, large area (4 mm(2)) electrodes were used. The electrode surface is also micro-structured with an array of gold mushroom-like shapes to further enhance the active area. In comparison with a flat gold surface, the micro-structured surface increases the capacitance of the electrode/electrolyte interface by 54%. The electrode low impedance and low noise enable the detection of weak and low frequency quasi-periodic signals produced by astrocytes populations that thus far had remained inaccessible using conventional extracellular electrodes. Signals with 5 mu V in amplitude and lasting for 5-10 s were measured, with a peak-to-peak signal-to-noise ratio of 16. The electrodes and the methodology developed here can be used as an ultrasensitive electrophysiological tool to reveal the synchronization dynamics of ultra-slow ionic signalling between non-electrogenic cells.
- Social organization and endocrine profiles of Australoheros facetus, an exotic freshwater fish in southern PortugalPublication . Baduy, F.; Silva, FBV; Guerreiro, Pedro M; Canario, A.V.M.; L. Saraiva, JoãoAustraloheros facetus is a neotropical cichlid and an exotic species in the Guadiana and Odelouca basins (Southern Portugal). In this research, we aimed to characterize the main behavioural patterns and circulating hormones, 17 beta-estradiol (E-2) for females, and testosterone, 11-ketotestosterone (11KT) and cortisol for both sexes, during the formation of social groups, a crucial step in the life-history of A. facetus. A pair-breeding strategy with territorial behaviour and aggressive interactions was found, with a positive correlation between dominance and size for both sexes. There were no significant differences between non-territorial and territorial individuals in the baseline levels of hormones, but 11KT was higher in males when they became territorial, as E-2 for territorial females, while there was no clear pattern for testosterone. In contrast, cortisol was higher in non-territorial males and correlated negatively with social dominance. These results suggest that size is the main driver for social dominance and that formation of stable hierarchies result in higher circulating 11KT and lowers stress in territorial males. Related to A. facetus' behaviour, aggressiveness and biparental care may be an advantage during the invasion process of A. facetus, facilitating colonization of new habitats.
- Introduction to RISC-KIT: resilience-increasing strategies for coastsPublication . Van Dongeren, Ap; Ciavola, Paolo; Martinez, Grit; Viavattene, Christophe; Bogaard, Tom; Ferreira, Óscar; Higgins, Ruth; McCall, RobertIn this paper an introduction is provided to the RISC-KIT project’s goals, products and applications, which is the subject of this Special Issue. Subsequent papers provide the details on the developed tools and their application on ten case study sites in Europe.
- MicroRNAs in lung cancerPublication . Castro, Diana; Moreira, Marcia; Gouveia, Alexandra Monteiro; Pozza, Daniel Humberto; De Mello, Ramon AndradeLung cancer (LC) is a serious public health problem responsible for the majority of cancer deaths and comorbidities in developed countries. Tobacco smoking is considered the main risk factor for LC; however, only a few smokers will be affected by this cancer. Current screening methods are focused on identifying the early stages of this malignancy. Thus, new data concerning the roles of microRNA alterations in inflammation, epithelial-mesenchymal transition and lung disease have increased hope about LC pathogenesis, diagnosis, treatment and prognosis. MicroRNA mechanisms include angiogenesis promotion, cell cycle regulation by modulating cellular proliferation and apoptosis, and migration and invasion inhibition. In this context, this manuscript reviews the current information about many important microRNAs as they relate to the initiation and progression of LC.
- Alkane coiling in perfluoroalkane solutions: a new primitive solvophobic effectPublication . Morgado, Pedro; Garcia, Ana; Martins, Luis F. G.; Illiarco, Laura M.; Filipe, Eduardo J. M.In this work, we demonstrate that n-alkanes coil when mixed with perfluoroalkanes, changing their conformational equilibria to more globular states, with a higher number of gauche conformations. The new coiling effect is here observed in fluids governed exclusively by dispersion interactions, contrary to other examples in which hydrogen bonding and polarity play important roles. FTIR spectra of liquid mixtures of n-hexane and perfluorohexane unambiguously reveal that the population of n-hexane molecules in all-trans conformation reduces from 32% in the pure n-alkane to practically zero. The spectra of peffluorohexane remain unchanged, suggesting nanosegregatiori of the hydrogenated and fluorinated chains. Molecular dynamics simulatiOns support this analysis. The new solvophobic effect is prone to have a major impact on the structure, organization, and therefore thermodynamic properties and phase equilibria of, fluids involving mixed hydrogenated and fluorinated chains.
- Oomycota species associated with deciduous and coniferous seedlings in forest tree nurseries of Western TurkeyPublication . Lehtijarvi, A.; Kaya, A. G. Aday; Woodward, S.; Jung, Thomas; Lehtijarvi, H. T. DogmusOccurrence and pathogenicity of Oomycota species causing root rot were investigated in 10 forest tree nurseries in western Turkey. Soil samples (129 in total) taken from the rhizosphere of symptomatic seedlings were baited for Oomycota using young leaves of Quercus suber, Rhododendron simsii and R.ponticum. Oomycota (178 isolates) were obtained by culturing on selective media, and identified using morphological methods followed by PCR and sequencing of the ITS rDNA and cox1 regions. Phytophthora aff. cactorum, P.citricola sensu lato, P.crassamura, P.syringae, Pythium aphanidermatum, Py.intermedium, Py.irregulare, Py.ultimum and Phytopythium vexans were common amongst the isolates. The highest diversity of Oomycota was found in the forest nurseries at Adapazar-Hendek and zmir-Torbal. Pathogenicity tests showed that the isolates caused lesions on a range of host plants. The importance of these nursery infections in transferring potentially damaging oomycete species to Turkish forests is discussed.
- A citricultura portuguesa. Desafios e ameaças.Publication . Duarte, AmílcarOs citrinos são uma cultura importante em Portugal desde o séc. XVI, sendo o Algarve a principal região citrícola do país. A meados do séc. XX houve um grande aumento da área de cultivo no Algarve, tendo a citricultura passado a constituir o principal sector da agricultura da região e um dos principais sectores da fruticultura nacional. Nos últimos anos, tem havido um aumento da área média dos pomares, com abandono de pequenas parcelas, enquanto os maiores produtores têm vindo a fazer grandes plantações. Isto tem sido acompanhado de uma modernização tecnológica, parcialmente relacionada com o aumento do número de agrónomos responsáveis pela condução técnica das explorações citrícolas. Além disso, muitos pomares passaram a ser geridos tecnicamente pelas organizações de produtores que comercializam a fruta. Estas alterações, juntamente com a modernização das centrais, fizeram com que hoje os citrinos produzidos em Portugal tenham um elevado nível de qualidade e uma boa apresentação, o que permite fazer a sua comercialização nos mercados mais exigentes. Apesar dos progressos e potencialidade referidos, podemos dizer que a citricultura portuguesa está hoje ameaçada de morte. Além da já conhecida ameaça da Tristeza dos citrinos, temos hoje uma nova ameaça, o huanglongbing (HLB), também conhecida por greening, uma das doenças mais graves dos citrinos, uma vez que reduz muito a produtividade das árvores, tornando inviável o seu cultivo em zonas onde está instalada. Esta doença é provocada por uma bactéria e é transmitida por psilas, entre elas, a psila africana dos citrinos (Trioza erytreae). Esta psila foi introduzida no norte do país e tem-se vindo a disseminar para sul pela zona costeira, estando já na Figueira da Foz, e recentemente foi descoberto um novo foco em Sintra.
- Klotho levels: association with insulin resistance and albumin-to-creatinine ratio in type 2 diabetic patientsPublication . Silva, Ana Paula; Mendes, Filipa; Pereira, Luisa; Fragoso, André; Baptista Gonçalves, Rui; Santos, Nelio; Rato, Fátima; Neves, Pedro LeãoThe present study aimed at evaluating the relationship between Klotho levels and insulin resistance and albumin-to-creatinine ratio (ACR) in type 2 diabetic patients with CKD. We conducted an observational, cross-sectional study in our outpatient diabetic nephropathy clinic from 2014 to 2016, enrolling a total of 107 type 2 diabetic patients with stage 2-3 CKD, with a mean age of 59 years. Several clinical and laboratorial parameters were evaluated, including those related to mineral and carbohydrate metabolism. The mean eGFR at baseline was 53.2 mL/min, and the mean levels of ACR and Klotho were 181.9 A mu g/mg and 331.1 pg/m, respectively. In the simple linear regression model, Klotho levels were correlated with age, phosphorus, PTH, ACR, HOMA, IL-6, FGF-23, OxLDL, eGFR and vitamin D levels. Applying a multivariate linear regression model, only the ACR, HOMA-IR, FGF-23 and vitamin D independently influenced the Klotho levels. In the generalized linear model, only the Klotho groups were statistically significant as independent variable (p = 0.007). The results show that the group 1 (< 268) compared with group 3 (> 440) had higher odds in the higher ACR (ae181), ORa = 3.429, p = 0.014. There were no statistically significant differences between Klotho groups 2 and 3, and the HOMA-IR obtained showed that group 1 (< 268) had greater odds of HOMA-IR ae2 when compared with group 3 (> 440), ORa = 21.59, p = 0.017. Our results showed that Klotho levels are influenced by FGF23, vitamin D and insulin resistance. This suggests that Klotho levels might be affected by renal function as well as having a relevant role on insulin metabolism and ACR homeostasis.
- Resource design in constrained networks for network lifetime increasePublication . Correia, Noélia; Mazayev, Andriy; Schutz, G.; A. Martins, J.; Barradas, A.As constrained "things" become increasingly integrated with the Internet and accessible for interactive communication, energy efficient ways to collect, aggregate, and share data over such constrained networks are needed. In this paper, we propose the use of constrained RESTful environments interfaces to build resource collections having a network lifetime increase in mind. More specifically, based on existing atomic resources, collections are created/designed to become available as new resources, which can be observed. Such resource design should not only match client's interests, but also increase network lifetime as much as possible. For this to happen, energy consumption should be balanced/fair among nodes so that node depletion is delayed. When compared with previous approaches, results show that energy efficiency and network lifetime can be increased while reducing control/registration messages, which are used to set up or change observations.