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- Environmental influence on commercial fishery landings of small pelagic fish in PortugalPublication . Teixeira, Célia M.; Gamito, Rita; Miguel de Sousa Leitão, Francisco; Murta, Alberto G.; Cabral, Henrique N.; Erzini, Karim; Costa, Maria JoséSmall pelagic fishes are particularly abundant in areas with high environmental variability (zones of coastal upwelling and areas of tidal mixing and river discharge), and because of this, their abundance suffers large inter-annual and inter-decadal fluctuations. In Portugal, the most important species in terms of landings are European sardine, Atlantic horse mackerel and Atlantic chub mackerel. Small pelagic fish landings account for 62.8 % of the total fish biomass and represent 32.7 % of the economical value of all catches. We have investigated trends in landings of these small pelagic fishes and detected the effects of environmental factors in this fishery. In order to explain the variability of landings of small pelagic fishes, we have used official landings (1965-2012) for trawling and purse seine fisheries and applied generalized linear models, using the North Atlantic Oscillation index (NAO) (annual and winter NAO index), sea surface temperature (SST), wind data (strength and North-South and East-West wind components) and rainfall, as explanatory variables. Regression analysis was used to describe the relationship between landings and SST. The models explained between 50.16 and 51.07 % of the variability of the LPUE, with the most important factors being winter NAO index, SST and wind strength. The LPUE of European sardine and Atlantic horse mackerel was negatively correlated with SST, and LPUE of Atlantic chub mackerel was positively correlated with SST. The use of landings of three important species of small pelagic fishes allowed the detection of variations in landings associated with changes in sea water temperature and NAO index.
- How heat alters underlying deposits and implications for archaeological fire features: A controlled experimentPublication . Aldeias, Vera; Dibble, Harold L.; Sandgathe, Dennis; Goldberg, Paul; McPherron, Shannon J. P.While it is true that the use of fire is undoubtedly an important behavioral trait, fire can also leave important traces in archaeological deposits, including altering previously deposited sediments and artifacts. The set of controlled experiments reported here do not focus on fire per se, but rather on the effects of some of the most important variables underlying the transfer of heat to subsurface sediments. These variables, including temperature, duration, sediment type, moisture, and mineralogy, are altered here in ways that essentially bracket the range of conditions under which past fires may have existed. The results show that sediments as much as 10 cm directly below a heat source routinely reach temperatures of 200 degrees C, with higher temperatures and greater depth of heat transfer possible with longer durations or higher surface temperatures. One of the implications of these results is that a surface can produce substantial thermal-alterations of archaeological artifacts and sediments deposited much earlier in the sequence. Likewise, there are significant implications for the analyses and chronometric dating of thermally altered sediments and burned artifacts. (C) 2016 Elsevier Ltd. All rights reserved.
- Genetic diversity and local connectivity in the mediterranean red gorgonian coral after mass mortality eventsPublication . Pilczynska, Joanna; Cocito, Silvia; Boavida, Joana; Serrão, Ester; Queiroga, HenriqueEstimating the patterns of connectivity in marine taxa with planktonic dispersive stages is a challenging but crucial task because of its conservation implications. The red gorgonian Paramuricea clavata is a habitat forming species, characterized by short larval dispersal and high reproductive output, but low recruitment. In the recent past, the species was impacted by mass mortality events caused by increased water temperatures in summer. In the present study, we used 9 microsatellites to investigate the genetic structure and connectivity in the highly threatened populations from the Ligurian Sea (NW Mediterranean). No evidence for a recent bottleneck neither decreased genetic diversity in sites impacted by mass mortality events were found. Significant IBD pattern and high global F-ST confirmed low larval dispersal capability in the red gorgonian. The maximum dispersal distance was estimated at 20-60 km. Larval exchange between sites separated by hundreds of meters and between different depths was detected at each site, supporting the hypothesis that deeper subpopulations unaffected by surface warming peaks may provide larvae for shallower ones, enabling recovery after climatically induced mortality events.
- Os compostos no controlo de doenças das plantasPublication . Reis, MárioA compostagem permite obter produtos, designados compostados ou compostos, que em alguns casos, apresentam a capacidade de reduzir ou eliminar doenças das plantas com origem no solo - capacidade supressiva ou supressividade - o que lhes confere um interesse acrescido ao de fertilizantes agrícolas, objectivo com que habitualmente se empregam. Neste trabalho, após breve descrição da compostagem, são referidos os mecanismos de supressividade, as condições para a obtenção de compostos supressivos, os métodos de quantificação da supressividade e referem-se alguns exemplos de compostos com capacidade supressiva. O conhecimento sobre a capacidade supressiva dos compostos é uma área de estudo com grande carência de conhecimento, mas que apresenta um enorme interesse, em particular numa perspectiva de produção agrícola mais sustentável e com menor impacte ambiental.
- A comparative evaluation of biological activities and bioactive compounds of the seagrasses Zostera marina and Zostera noltei from southern PortugalPublication . Custódio, Luísa; Laukaityte, Simona; Engelen, Aschwin; Rodrigues, Maria Joao; Pereira, Hugo; Vizetto-Duarte, C; Barreira, Luísa; Rodriguez, Hortensia; Albericio, Fernando; Varela, JoãoThis work assessed the antioxidant potential, acetylcholinesterase (AChE) inhibition and the in vitro cytotoxic activity of extracts of the seagrasses Zostera marina and Zostera noltei collected from southern Portugal. The total phenolic contents (TPCs), the rosmarinic acid (RA) concentration (HPLC/DAD) and the fatty acid (FA) profile (GC/MS) are also described. Z. marina had the highest TPC, radical scavenging activity against DPPH radicals and copper chelating activity. Z. noltei had metal chelation capacity to copper and iron ions. None of the species was able to inhibit AChE. Both seagrasses had high levels of polyunsaturated FAs. Z. marina significantly and selectively reduced the viability of tumorous neuronal cells. Z. noltei was highly toxic for the three cell lines tested and was selective against hepatocarcinoma cells at the concentration of 100g/mL. RA was the main compound identified in Z. marina, but not in Z. noltei.
- Tolerance mechanisms of three potted ornamental plants grown under moderate salinityPublication . Garcia-Caparros, Pedro; Llanderal, Alfonso; Pestana, Maribela; Correia, Pedro José; Teresa Lao, MariaThe scarcity of water in the Mediterranean area has frequently led to the use of saline water in order to irrigate ornamental plants in many nurseries. However, before the large-scale use of such waters, the ways in which the plants deal with the salinity need to be evaluated. Plants of Aloe vera L. Burm, Kalanchoe blossfeldiana Poelln and Gazania splendens Lem sp. were grown in pots with a mixture of sphagnum peat moss and Perlite. In order to evaluate the effects of different levels of salinity, three treatments using different NaCl concentrations (Electrical conductivity = 2.0 (control), 4.5 and 7.5 dS m(-1)) were applied over a period of 60 days. At the end of the experiment, the growth, physiological parameters and mineral content of the roots and leaves were assessed for each salinity treatment. After 60 days of exposure to salinity, the total biomass of all species decreased similarly. The mineral composition of roots and leaves was clearly affected. Osmolytes, such as praline, played an important role in the osmotic adjustment in all species increasing in the roots and leaves at the higher ECi. Different mechanisms of the salt tolerance were triggered in each species. A vera plants showed Na+ accumulation at the root level and a decrease in succulence index of leaves. K. blossfeldiana plants shed leaves to release Na+ and G. splendens plants accumulated Cl- and Na+ at the root level, secreted salt from leaves, lost salt by shedding of old leaves and increased the succulence index of remaining leaves. We concluded that the use of saline waters is feasible for growing these ornamental plants, and G. splendens seems to be particularly well adapted to salinity, a consideration that is particularly relevant in arid saline areas. (C) 2016 Elsevier B.V. All rights reserved.
- Pilocytic astrocytomaPublication . Lourenço, Eva Patrícia; Nzwalo, Hipólito; Sampaio, Mário Rui; Varela, Ana VerónicaPilocytic astrocytoma (PA) is a benign tumour of childhood, often located in deep midline structures such as the brainstem and the cerebellum.1 Gross surgical resection is curative in the majority of patients.2 We report a case of recurrent PA diagnosed after an acute confusional state and rightsided spastic hemiparesis in a previously healthy 38-year-old woman. Her initial brain CT showed a left temporal mass causing obstructive hydrocephalus (figure 1A–C). Acute surgical extraction was performed (figure 1D) and the biopsy confirmed the diagnosis of PA grade I (WHO). The patient remained clinically asymptomatic for 1 year, when a progressive headache emerged. At this time, the neurological examination disclosed the presence of dysarthria and right-sided hemiparesis with facial involvement. Brain MRI showed the presence of recurrent PA (figure 1E, F). The patient again underwent surgery due to the mass effect and brainstem compression caused by the tumour, and the diagnosis of PA was reconfirmed histologically. The patient fully recovered after the intervention. PA occurs commonly in the first 2 decades of life.1 Information on the characteristics of PA in adulthood is scarce due to its rarity. Some studies indicate the adult prognosis to be similar to that in children, while others indicate that PA may show aggressive behaviour with tumour recurrence and death.2 Anaplastic features are associated with worse prognosis, but little is known about the value of genetic characterisation in adulthood PA.3 In conclusion, this case offers a unique description of adult onset PA in an atypical location outside the midline structures, and also provides an example of early recurrence.
- Understanding COPD: A vision on phenotypes, comorbidities and treatment approachPublication . Fragoso, E.; André, S.; Boleo-Tome, J. P.; Areias, Vanda; Munha, J.; Cardoso, J.Chronic Obstructive Pulmonary Disease (COPD) phenotypes have become increasingly recognized as important for grouping patients with similar presentation and/or behavior, within the heterogeneity of the disease. The primary aim of identifying phenotypes is to provide patients with the best health care possible, tailoring the therapeutic approach to each patient.However, the identification of specific phenotypes has been hindered by several factors such as which specific attributes are relevant, which discriminant features should be used for assigning patients to specific phenotypes, and how relevant are they to the therapeutic approach, prognostic and clinical outcome. Moreover, the definition of phenotype is still not consensual. Comorbidities, risk factors, modifiable risk factors and disease severity, although not phenotypes, have impact across all COPD phenotypes.Although there are some identified phenotypes that are fairly consensual, many others have been proposed, but currently lack validation. The on-going debate about which instruments and tests should be used in the identification and definition of phenotypes has contributed to this uncertainty.In this paper, the authors review present knowledge regarding COPD phenotyping, discuss the role of phenotypes and comorbidities on the severity of COPD, propose new phenotypes and suggest a phenotype-based pharmacological therapeutic approach. The authors conclude that a patient-tailored treatment approach, which takes into account each patient's specific-attributes and specificities, should be pursued. (c) 2016 Sociedade Portuguesa de Pneumologia. Published by Elsevier Espana, S.L.U.
- Hotel employees: a systematic literature reviewPublication . Borralha, Sérgio; Jesus, Saúl; Pinto, PatríciaWith the increase of studies on hospitality professionals over the years, it is essential to perform a review on those works. This review was conducted through the databases Web of Knowledge, Web of Science (Social Sciences Index Expanded, Social Sciences Citation Index, Medline), and Science Direct. We searched for articles published between 2000 and 2014, crossing the keywords ?hospitality?, ?tourism?, and ?hotel? with the keywords ?professionals?, ?employees?, and ?workers?. Our aim was to identify the most studied variables on hospitality employees. The search process resulted on 3700 initial references, being selected 242. We verified that work satisfaction was studied in 51 articles and stress, burnout, and mental exhaustion in 31. For that reason, this review aggregates and analyses these results. This study has implications for the understanding of the roll of these variables in hospitality and tourism economic profitability, as well as in human resources management policies and individual well-being.
- Co-authorship networks: Collaborative research structures at the journal levelPublication . Santos, José António C.; Santos, Margarida CustódioPresent-day research is, in most cases, the outcome of collaborative research, as evidenced by the fact that most papers are authored by two or more researchers. This study?s general goal was to examine the evolution and structure of scientific collaborative networks revealed by papers published in the Tourism & Management Studies journal over a five-year period, from 2011 to 2015, as well as to represent these networks graphically. In this paper, we seek to offer a clear assessment of intra-institutional, inter-institutional and international collaborations and to identify primary author networks and the role of gender in their composition. To reach these goals, we used a combination of bibliometric analysis with social network analysis. The results demonstrate that geographic proximity and linguistic affinity play a substantial role in scientific collaboration between institutions. In fact, most papers result from collaborative research involving two or more authors from the same institution. A gender analysis of the universe of authors and co-authors and of the role of women in the composition of co-authorship networks demonstrated that most networks include women and that, in most networks, women have a leading position, which is consistent with their weight (51.3%) in the universe of authors. This is one of the first studies to demonstrate that women are taking the lead in tourism and management research.