Percorrer por autor "Mendes, S."
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- Effect of rearing temperature in the growth of hatchery reared juveniles of the sea cucumber Holothuria arguinensis (Koehler & Vaney, 1906)Publication . Madruga, A.S.; Félix, P.M.; Sousa, J.; Silva, F. Azevedo e; Brito, A.C.; Mendes, S.; Pombo, A.Since the early 1980's there has been an increase in sea cucumber harvest and trade, mainly due to Asiatic market pressure. In the Indo-Pacific regions, the collapse of various stocks of these echinoderms has already occurred due to overfishing. In Europe, sea cucumber exportation depends exclusively on wild stock harvesting, which has demonstrated to be an unsustainable method to supply the markets, as these species are highly susceptible to overfishing. To enable a sustainable development of this emerging market in Europe the need to develop aquaculture techniques for these animals becomes of the utmost importance. At the current early stages of development, the viability of sea cucumber aquaculture for temperate species depends on the optimization of the rearing conditions. As ectotherms, temperature proves to be one of the most relevant parameters that affects the growth of sea cucumbers, as it influences metabolism and energy management and, in turn, future rearing methods and aquaculture sites. Therefore, this study aimed to determine the influence of temperature on the growth of H. arguinensis juveniles. A group of 168 juveniles (3.25 g ± 0.21; 3.81 cm ± 0.31) were placed under four different temperature treatments 18, 20, 22 and 24 ◦C for 4 months. The highest length (1.45 cm ± 0.16) and weight (2.79 g ± 0.14) gain were recorded at 20 ◦C. Similarly, the 20 ◦C treatment also produced the highest values for specific growth rate (0.50%/day) and the daily body length rate (0.30%cm/day). All allometric coefficients showed negative allometry (b < 3), a growth strategy that accentuates with increasing size. This lifehistory trait shows a higher distance from isometry the more distance the animals are from their optimum stocking temperature. Hence, metrics like the Fulton condition factor (K) show an inadequacy for the assessment of sea cucumber's condition, because a higher relative length decreases the value of K. A rearing temperature of 20 ◦C resulted in the best growth overall considering all increments in length and weight, pointing towards this as the best rearing temperature for the temperate species, H. arguinensis.
- Effects of sewage pollution on the structure of rocky shore macroinvertebrate assemblagesPublication . Cabral-Oliveira, J.; Mendes, S.; Maranhão P.; Pardal, M. A.The urgency to find efficient indices and indicators to prevent further deterioration of coastal areas is one of the hot topics in today’s scientific publication. However, a detailed knowledge of community responses to anthropogenic impacts is essential to sustain those indices. The studies on the response of benthic community to sewage pollution on intertidal rocky shores are generally based on visual census and do not take into account the tidal levels. In order to fulfil this gap in this study: (i) the sampling was performed by destructive sampling, with all individuals identified to the species level; (ii) the sampling was done at all levels of the intertidal (sublittoral fringe, eulittoral, and littoral fringe). Sewage pollution changed the environmental variables and the abundance of macroinvertebrates, being Mytilus galloprovincialis, Melarhaphe neritoides, and Chthamalus montagui the species most responsible for the dissimilarities observed. Effects were different on the three intertidal zones: community structure changed in the sublittoral fringe; suspension-feeders abundances and species richness increased in the eulittoral; no differences were detected in the littoral fringe. Moreover, the results confirm that the presence of sewage discharges tended to benefit suspension feeders, and that the sensitive species were replaced by opportunistic ones.
- Höpüpü: surfing stoked on the waves of Peniche. The surfer and the satisfaction with his surf tourism experiencePublication . Nunes, J.M.; Mendes, S.; Jorge, J.P.More recently, surf has acquired an overwhelming dimension, both in terms of media coverage and in terms of economic relevance and direct impact in the communities. The Portuguese situation is a clear reflection of that, especially in Peniche, where this phenomenon is part of strategic documentation related with the “Sea economy”, namely via the so called “Surf Tourism”. Nowadays, Portugal is referred to as one of the most attractive countries as a tourist destination as a whole, but also as a tourist destination of reference when it comes to surfing. Furthermore, Peniche is one of the key locations for these activities, with an increasing range of packages and surf tourism offers, especially taking advantage of their environment, landscape and other characteristics related to nature. The main purpose of this work is to characterize in detail the “surfer/surf tourist” at Peniche and measure his satisfaction with this site as a surf tourism destination. In addition, it is proposed to the “surfer/surf tourist” to evaluate the satisfaction versus the level and quality of surf found. In order to achieve this purpose, a comprehensive survey was produced and conducted. The target was visitors of Peniche that matched to the typical “surfer/surf tourist”, achieving a response rate of 363 individuals. The results obtained and the knowledge produced as an outcome of this investigation lead us to build the profile of the “surfer/surf tourist” visiting Peniche in association with his expectative. Also, the study allowed leveraging policies and strategies directly addressing the expectations of this particular market niche in order to – using a sustainable approach – maximizing the potential of this activity.
- Negative impact on the reproductive potential of blue jack mackerel Trachurus picturatus by Kudoa infection of the ovaryPublication . Neves, A.; Gordo, I.; Sequeira, V.; Vieira, A.R.; Silva, E.; Silva, F.; Duarte, A.M.; Mendes, S.; Ganhão, R.; Peleteiro, M.C.; Assis, C.; Rebelo, R.; Magalhães, M.F.; Gil, M. M.; Gordo, L.S.Reproduction of Trachurus picturatus off the western Portuguese coast was studied over 1 yr. During histological analyses, the presence of Kudoa sp. was detected in advanced vitellogenic oocytes. Kudoa infections are known to cause economic loss through the induction of postmortem liquefaction of fish muscles, but ovarian infection as reported in this study will seriously affect the reproductive potential of the species and thus impact fisheries productivity. Only females showed gonad infection which led to total degradation of advanced vitellogenic oocytes. No macroscopic, somatic or condition indices revealed differences between infected and uninfected females, rendering this infection event a concealed suppression of reproduction.
- Oral health-related quality of life in portuguese pre-school children: a cross-sectional studyPublication . Graça, S. R.; Dias, S.; Mendes, S.Purpose To study Oral Health related Quality of Life (OHRQoL) of pre-school children and its associated factors. Methods Cross-sectional study with sample data collected through an on-line questionnaire to a non-probabilistic sample. The questionnaire included the Portuguese version of the Early Childhood Oral Health Impact Scale (ECOHIS) and questions about sociodemographic characteristics, oral health behaviours, and reported oral health of the child. Data analyses included descriptive statistics, Mann–Whitney and Kruskal–Wallis tests and Linear regression (α=0.05). Results The sample consisted of 1475 parents of pre-school children (3–5 years-old), residing in Portugal. The mean ECOHIS total score was 1.5 (sd=3.4). In the bivariate analysis the child’s age, starting toothbrushing after one year of age, frequent intake of sugary food and drinks, previous appointment with an oral health professional, all reported of oral health problems, and a negative perception of oral health were negatively associated with OHRQoL (p<0,05). In the regression model the factors that most contributed to a worse quality of life were dental caries and abscess, contributing to an ECOHIS average increase of 2.56 and 3.34, respectively. Conclusions The studied population presented a good OHRQoL, with the item related to pain being the most relevant for the ECOHIS score. Worst OHRQoL was found in older children, whose parents negatively rated the children's oral health and with reported dental caries, trauma, and abscess.
- Surf: royal sport for the natural kings of earth: uma perspetiva históricaPublication . Nunes, J.M.; Mendes, S.; Jorge, J.P.In recent years, surf has reached such proportions in terms of media coverage and importance in the Portuguese economy such a way that even attracted the government's attention to the phenomenon. This attention was reflected in national strategic documents of the economy of the sea, through the surf tourism. Nowadays Portugal is mentioned as one of the countries with the highest tourist demand for surfing, which is reflected in the increasing availability of products relating to this activity, including hostels, surfcamps and surfschools, among others. As a first introduction we refer to the origin of the word surf, as well as their differentiation relative to the term surfing, some of the modalities that are practiced in the waves, chronologically followed by their origin, history, social issues and decline, with the connection to surf tourism at the beginning of the 20th century proving to be extremely important to your success and rebirth, while economic activity and subsequent development. In the end, globalization, finishing with its arrival in Portugal.
- The influence of light and culture media on the growth of the red seaweed Gracilaria gracilis (Rhodophyta, Gracilariales) under laboratory conditionsPublication . Freitas, M.V.; Correia, A.; Ribeiro, J.; Pereira, C.; Afonso, C.; Gil, M.M.; Mendes, S.; Baptista, T.; Mouga, T.
- Using the mini-VIDAS® Easy Salmonella protocol to assess contamination in transitional and coastal watersPublication . Rodrigues, M. J.; Martins, K.; Garcia, D.; Ferreira, Susana; Gonçalves, Sílvia; Mendes, S.; Lemos, MarcoClassical methodologies for Salmonella detection may be too long in time to assure public safety. Presently, one of the fastest assays for Salmonella detection using the mini-VIDAS® system is the Easy Salmonella protocol. This assay, developed for food matrixes analysis, was here assessed for the applicability on the detection of these bacteria in transitional and saltwaters. The presence of Salmonella was detected in 4.2 % of the samples studied. In these transitional waters, the proposed protocol presented an efficiency of 79.1 %, due to a high false positive rate (20.8 %), and a false negative rate of 0 %—implying reducing analysis time, the use of enrichment broths, and making it more cost effective. Despite the multitude of samples nature, the method here described revealed to be an efficient and promising tool for transitional waters analysis.