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Vulcanodinium rugosum, a recently described species, produces pinnatoxins. The IFR-VRU-01 strain, isolated from a French Mediterranean lagoon in 2010 and identified as the causative dinoflagellate contaminating mussels in the Ingril Lagoon (French Mediterranean) with pinnatoxin-G, was grown in an enriched natural seawater medium. We tested the effect of temperature and salinity on growth, pinnatoxin-G production and chlorophyll a levels of this dinoflagellate. These factors were tested in combinations of five temperatures (15, 20, 25, 30 and 35 °C) and five salinities (20, 25, 30, 35 and 40) at an irradiance of 100 µmol photon m−2 s−1. V. rugosum can grow at temperatures and salinities ranging from 20 °C to 30 °C and 20 to 40, respectively. The optimal combination for growth (0.39 ± 0.11 d−1) was a temperature of 25 °C and a salinity of 40. Results suggest that V. rugosum is euryhaline and thermophile which could explain why this dinoflagellate develops in situ only from June to September. V. rugosum growth rate and pinnatoxin-G production were highest at temperatures ranging between 25 and 30 °C. This suggests that the dinoflagellate may give rise to extensive blooms in the coming decades caused by the climate change-related increases in temperature expected in the Mediterranean coasts.

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The geological evolution of coastal and marine environments offshore the Cilento Promontory through marine geological mapping is discussed here. The marine geological map n. 502 “Agropoli,” located offshore the Cilento Promontory (southern Italy), is described and put in regional geologic setting. The study area covers water depths ranging between 30 and 200 m isobaths. The geologic map has been constructed in the frame of a research program financed by the National Geological Survey of Italy (CARG Project), finalized to the construction of an up-to-date cartography of the Campania region. Geological and geophysical data on the continental shelf and slope offshore the southern Campania region have been acquired in an area bounded northward by the Gulf of Salerno and southward by the Gulf of Policastro. A high-resolution multibeam bathymetry has permitted the construction of a digital elevation model (DEM). Sidescan sonar profiles have also been collected and interpreted, and their merging with bathymetric data has allowed for the realization of the base for the marine geologic cartography. The calibration of geophysical data has been attempted through sea-bottom samples. The morpho-structures and the seismic sequences overlying the outcrops of acoustic basement reported in the cartographic representation have been studied in detail using single-channel seismics. The interpretation of seismic profiles has been a support for the reconstruction of the stratigraphic and structural setting of the Quaternary continental shelf successions and the outcrops of rocky acoustic basement in correspondence to the Licosa Cape morphostructural high. These areas result from the seaward prolongation of the stratigraphic and structural units, widely cropping out in the surrounding emerged sector of the Cilento Promontory. The cartographic approach is based on the recognition of laterally coeval depositional systems, interpreted in the frame of system tracts of the Late Quaternary depositional sequence.

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This work evaluates the mercury (Hg) contamination status (sediments and biota) of the Bijagós archipelago, off the coast of Guinea-Bissau. Sediments exhibited very low concentrations (<1-12ngg(-1)), pointing to negligible sources of anthropogenic Hg in the region. Nevertheless, Hg is well correlated to the fine fraction, aluminium, and loss on ignition, indicating the effect of grain size and organic matter content on the presence of Hg in sediments. Mercury in the bivalves Tagelus adansoni and Senilia senilis did not vary considerably among sites, ranging within narrow intervals (0.09-0.12 and 0.12-0.14μgg(-1) (dry weight), respectively). Divergent substrate preferences/feeding tactics may justify slight differences between species. The value 11ngg(-1) is proposed as the sediment background concentration for this West-African coastal region, and concentrations within the interval 8-10ngg(-1) (wet weight) may be considered as reference range for S. senilis and T. adansoni in future monitoring studies.

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This thesis examines digital technologies policies designed for Australian schools and the ways they are understood and interpreted by students, school staff, teachers, principals and policy writers. This study explores the ways these research participant groups interpret and understand the ‘ethical dimension’ of schools’ digital technologies policies for teaching and learning. In this thesis the ethical dimension is considered to be a dynamic concept which encompasses various elements including; decisions, actions, values, issues, debates, education, discourses, and notions of right and wrong, in relation to ethics and uses of digital technologies in schools. In this study policy is taken to mean not only written texts but discursive processes, policy documents including national declarations, strategic plans and ‘acceptable use’ policies to guide the use of digital technologies in schools. The research is situated in the context of changes that have occurred in Australia and internationally over the last decade that have seen a greater focus on the access to and use of digital technologies in schools. In Australian school education, the attention placed on digital technologies in schools has seen the release of policies at the national, state, territory, education office and school levels, to guide their use. Prominent among these policies has been the Digital Education Revolution policy, launched in 2007 and concluded in 2013. This research aims to answers the question: What does an investigation reveal about understandings of the ethical dimension of digital technologies policies and their implementation in school education? The objective of this research is to examine the ethical dimension of digital technologies policies and to interpret and understand the responses of the research participants to the issues, silences, discourses and language, which characterise this dimension. In doing so, it is intended that the research can allow the participants to have a voice that, may be different to the official discourses located in digital technologies policies. The thesis takes a critical and interpretative approach to policies and examines the role of digital technologies policies as discourse. Interpretative theory is utilised as it provides a conceptual lens from which to interpret different perspectives and the implications of these in the construction of meaning in relation to schools’ digital technologies policies. Critical theory is used in tandem with interpretative theory as it represents a conceptual basis from which to critique and question underlying assumptions and discourses that are associated with the ethical dimension of schools’ digital technologies policies. The research methods used are semi-structured interviews and policy document analysis. Policies from the national, state, territory, education office and school level were analysed and contribute to understanding the way the ethical dimension of digital technologies policies is represented as a discourse. Students, school staff, teachers, principals and policy writers participated in research interviews and their views and perspectives were canvassed in relation to the ethical use of digital technologies and the policies that are designed to regulate their use. The thesis presents an argument that the ethical dimension of schools’ digital technologies policies and use is an under-researched area, and there are gaps in understanding and knowledge in the literature which remain to be addressed. It is envisaged that the thesis can make a meaningful contribution to understand the ways in which schools’ digital technologies policies are understood in school contexts. It is also envisaged that the findings from the research can inform policy development by analysing the voices and views of those in schools. The findings of the policy analysis revealed that there is little attention given to the ethical dimension in digital technologies at the national level. A discourse of compliance and control pervades digital technologies policies from the state, education office and school levels, which reduces ethical considerations to technical, legal and regulatory requirements. The discourse is largely instrumentalist and neglects the educative dimension of digital technologies which has the capacity to engender their ethical use. The findings from the interview conversations revealed that students, school staff and teachers perceive digital technologies policies to be difficult to understand, and not relevant to their situation and needs. They also expressed a desire to have greater consultation and participation in the formation and enactment of digital technologies policies, and they believe they are marginalised from these processes in their schools. Arising from the analysis of the policies and interview conversations, an argument is presented that in the light of the prominent role played by digital technologies and their potential for enhancing all aspects of school education, more research is required to provide a more holistic and richer understanding of the policies that are constructed to control and mediate their use.

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Ovarian sex cord-stromal tumors are infrequent and represent approximately 7% of all primary ovarian tumors. This histopathologic ovarian tumor group differs considerably from the more prevalent epithelial ovarian tumors. Although sex cord-stromal tumors present in a broad age group, the majority tend to present as a low-grade disease that usually follows a nonaggressive clinical course in younger patients. Furthermore, because the constituent cells of these tumors are engaged in ovarian steroid hormone production (e.g., androgens, estrogens, and corticoids), sex cord-stromal tumors are commonly associated with various hormone-mediated syndromes and exhibit a wide spectrum of clinical features ranging from hyperandrogenic virilizing states to hyperestrogenic manifestations. The World Health Organization sex cord-stromal tumor classification has recently been revised, and currently these tumors have been regrouped into the following clinicopathologic entities: pure stromal tumors, pure sex cord tumors, and mixed sex cord-stromal tumors. Moreover, some entities considered in the former classification (e.g., stromal luteoma, stromal tumor with minor sex cord elements, and gynandroblastoma) are no longer considered separate tumors in the current classification. Herein, we discuss and revise the ultrasonography, computed tomography, and magnetic resonance imaging characteristics of the different histopathologic types and clinicopathologic features of sex cord-stromal tumors to allow radiologists to narrow the differential diagnosis when facing ovarian tumors.

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The in vitro anti-fungal activity of leaf and stem bark of Daniella oliveri Rolfe was investigated against selected yeasts and moulds including dermatophytes. Water and methanol were used to extract the powdered leaf and stem bark using cold infusion. Antimicrobial activity was assessed by agar-well diffusion. Phytochemical analysis was carried out using standard procedures. The plant extracts were active against the test organisms at concentrations ranging from 3.125-100 mg/mL. The methanol extracts were more active than the aqueous extracts with the highest inhibition against the yeasts, Candida albicans and Candida krusei (MIC values of 3.125 mg/mL and 6.25 mg/mL respectively). Epidermophyton floccosum and Trichophyton interdigitale were the least inhibited of all the fungal strains. Phytochemical screening revealed the presence of tannins, anthraquinones, flavonoids, cardiac glycosides, alkaloids and saponins. The anti-fungal activity of Daniella oliveri as shown in this study indicates that the plant has the potential of utilisation in the development of chemotherapeutic agents for the treatment of relevant fungal infections.

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The hospitalizatíon of a child carnes with it major changes, etther in the child's life or parent. lllness and hospttalizatíon constitute a crisis situation for both the child and the famHy as it incorporates financiai, psychotogical, relational and social changes. The purpose of this work and analyze the satísfactíon and parents' perception on the importance of nursing care during hospttalizatíon and feelings experienced by parents. Objectives: To know the opinions and feelings of the parents in relation to the admlsston of the child 1n the service of Pediatrics at North of Portugal. Methods: Integrated this study parents of chtldren hospttalized in the pediatric inpatíent at the Hospital Trás-os-Montes e alto Douro, Vila Real, whose children were in the service to at least more than 48 hours, In total 33 escorts that replied to the questionnaire. For such a study we chose the type quantitative deschptíve. We proceeded to collect data by conductíng a questíonnaire, and the results of it were drafted in the SPSS program through Quantitatíve model wtth exploratory qualitatíve approach. Results: The age ofthe partícipants is between the 21 and 46 years - old, 75. 8% of respondents were married, 78. 8% of chtldren was hospitalized in the first time. We conclude that the mother is who else accompanies the chtld in the hospital. We had positive feedback regarding the interactíon parent-nurses since many parents stressed the good relatíonship with the nursing team (It reported that "Nurses" and "Nurses and "auxiliaries" were who else helped them, with 30. 3% and 21. 2% respectively). The feelings more mentioned were: anxiety -21 answers, sadness-20, fear-15 and hope with 15. The conditions offered to the parents were considered goodfor60.6%.

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O primeiro registro para o Atlântico Sul ocidental de uma espécie do gênero Malacoraja Stehmann, 1970 é feita com base na descrição de Malacoraja obscura, espécie nova, proveniente do talude continental do Sudeste brasileiro dos estados do Espírito Santo e Rio de Janeiro em profundidades de 808-1105 m. A espécie nova é conhecida através de cinco exemplares e é distinta de seus congêneres pela sua coloração dorsal composta por numerosas manchas esbranquiçadas e pequenas na região do disco e nadadeiras pélvicas, por apresentar uma fileira irregular de espinhos ao longo da superfície dorsal mediana da cauda a qual persiste em espécimes maiores (desde a base da cauda até dois-terços do seu comprimento numa fêmea de 680 mm de comprimento total, CT) e uma região pequena desprovida de dentículos na base ventral da cauda (estendendo somente até a margem distal da nadadeira pélvica). Outros caracteres diagnósticos em combinação incluem a ausência de espinhos escapulares em indivíduos maiores, número elevado de fileiras dentárias (64/62 fileiras num macho subadulto de 505 mm de CT e 76/74 numa fêmea de 680 mm de CT) e de vértebras (27-28 Vtr, 68-75 Vprd), coloração ventral do disco uniformemente castanha escura, duas fenestras pós-ventrais na cintura escapular, fenestra pós-ventral posterior grande, forame magno circular e dois forames para a carótida interna na placa basal ventral do neurocrânio. Machos adultos não são conhecidos, porém uma descrição anatômica de M. obscura, sp. nov., é fornecida. Comparações são realizadas com todo o material conhecido de M. kreffti, com a literatura sobre M. senta e com material abundante de M. spinacidermis da África do Sul; M. obscura, sp. nov., assemelha-se mais a M. spinacidermis do Atlântico Sul oriental em esqueleto dérmico, coloração e tamanho. Malacoraja é monofilético devido à sua espinulação e apêndices rostrais conspícuos e é aparentemente composta por dois grupos de espécies, um para M. obscura e M. spinacidermis e outro para M. kreffti e M. senta, porém a elucidação das relações filogenéticas entre as espécies necessita de mais informações anatômicas, principalmente das duas últimas espécies.

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The creation of thermostable enzymes has wide-ranging applications in industrial, scientific, and pharmaceutical settings. As various stabilization techniques exist, it is often unclear how to best proceed. To this end, we have redesigned Cel5A (HjCel5A) from Hypocrea jecorina (anamorph Trichoderma reesei) to comparatively evaluate several significantly divergent stabilization methods: 1) consensus design, 2) core repacking, 3) helix dipole stabilization, 4) FoldX ΔΔG approximations, 5) Triad ΔΔG approximations, and 6) entropy reduction through backbone stabilization. As several of these techniques require structural data, we initially solved the first crystal structure of HjCel5A to 2.05 Å. Results from the stabilization experiments demonstrate that consensus design works best at accurately predicting highly stabilizing and active mutations. FoldX and helix dipole stabilization, however, also performed well. Both methods rely on structural data and can reveal non-conserved, structure-dependent mutations with high fidelity. HjCel5A is a prime target for stabilization. Capable of cleaving cellulose strands from agricultural waste into fermentable sugars, this protein functions as the primary endoglucanase in an organism commonly used in the sustainable biofuels industry. Creating a long-lived, highly active thermostable HjCel5A would allow cellulose hydrolysis to proceed more efficiently, lowering production expenses. We employed information gleaned during the survey of stabilization techniques to generate HjCel5A variants demonstrating a 12-15 °C increase in the temperature at which 50% of the total activity persists, an 11-14 °C increase in optimal operating temperature, and a 60% increase over the maximal amount of hydrolysis achievable using the wild type enzyme. We anticipate that our comparative analysis of stabilization methods will prove useful in future thermostabilization experiments.

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The fossiliferous deposits in the coastal plain of the Rio Grande do Sul State, Southern Brazil, have been known since the late XIX century; however, the biostratigraphic and chronostratigraphic context is still poorly understood. The present work describes the results of electron spin resonance (ESR) dating in eleven fossil teeth of three extinct taxa (Toxodon platensis, Stegomastodon waringi and Hippidion principale) collected along Chui Creek and nearshore continental shelf, in an attempt to assess more accurately the ages of the fossils and its deposits. This method is based upon the analysis of paramagnetic defects found in biominerals, produced by ionizing radiation emitted by radioactive elements present in the surrounding sediment and by cosmic rays. Three fossils from Chui Creek, collected from the same stratigraphic horizon, exhibit ages between (42 +/- 3) Ka and (34 +/- 7) Ka, using the Combination Uptake model for radioisotopes uptake, while a incisor of Toxodon platensis collected from a stratigraphic level below is much older. Fossils from the shelf have ages ranging from (7 +/- 1) 10(5) Ka to (18 +/- 3) Ka, indicating the mixing of fossils of different epochs. The origin of the submarine fossiliferous deposits seems to be the result of multiple reworking and redeposition cycles by sea-level changes caused by the glacial-interglacial cycles during the Quaternary. The ages indicate that the fossiliferous outcrops at Chui Creek are much younger than previously thought, and that the fossiliferous deposits from the continental shelf encompass Ensenadan to late Lujanian ages (middle to late Pleistocene). (C) 2009 Elsevier Ltd and INQUA. All rights reserved.

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Crotalus durissus cascavella is a snake that is usually found in the scrublands of northeast Brazil. The components of its venom may have effects on the vascular and renal systems. Recently, a new bradykinin inhibitory peptide has been identified in the venom of the Crotalinae family. The aim of the present study was to investigate the renal and vascular effects of the natriuretic peptide isolated from the venom of Crotalus durissus cascavella (NP2_Casca). The chromatographic profile showed the fractionation of substances identified as convulxin, gyroxin, crotoxin and crotamine, as well as fractions V and VI. The electrophoretic profile of fraction V consisted of several bands ranging from approximately 6 kDa to 13 kDa, while fraction VI showed only two main electrophoretic bands with molecular weights of approximately 6 and 14 kDa. Reverse-phase chromatography showed that NP2_Casca corresponds to about 18% of fraction VI and that this fraction is the main natriuretic peptide. NP2_Casca was compared to other natriuretic peptides from other sources of snake venom. All amino acid sequences that were compared showed a consensus region of XGCFGX, XLDRIX and XSGLGCX. The group treated with NP2-Casca showed an increase in perfusion pressure, renal vascular resistance, urinary flow and glomerular filtration rate. The percent of total and proximal tubular transport of sodium was reduced significantly after administration of the peptide. The mean arterial pressure showed a dose-dependent decrease after infusion of NP2_Casca, and an increase in nitrite production. In the aortic ring assay, NP2_Casca caused a relaxant effect in endothelium-intact thoracic aortic rings precontracted with phenylephrine in the presence and absence of isatin. NP2_Casca failed to relax the aortic rings precontracted with an isosmotic potassium Krebs-Henseleit solution. In conclusion, the natriuretic peptide isolated from Crotalus durissus cascavella venom produced renal and vascular effects. NP2_Casca reduced total and proximal sodium tubular transport, leading to an increase in sodium excretion, thereby demonstrating a diuretic action. A hypotensive effect was displayed in an arterial pressure assay, with an increase in nitrite production, suggesting a possible vasoactive action. (C) 2008 Elsevier Ltd. All rights reserved.

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Size-related and seasonal evaluation of the dietary composition of fat snook (Centropomus parallelus Poey 1860) in the upper sector of an estuary of the southeastern coast of Brazil were carried out based on stomach analyses of specimens ranging from 40 to 170 mm standard length. Results reveal that C. parallelus is a carnivorous species feeding mainly on benthic crustaceans. Relatively high stomach replenishment suggests that this environment is an important feeding ground for fat snook juveniles. Multivariate analyses indicated that predator size effect is significantly more important than seasonal variation in determining dietary composition. Predator length was associated with increased consumption of palaemonid shrimps (Macrobrachium spp.) and grapsid crabs, and decreased foraging on tanaids (Kalliapseudes schubarti), thus showing a preference shift from smaller to larger prey. Predator length was also positively associated with an increase in the stomach repletion index. Additionally, allometric growth of both gape and head were consistently correlated with this ontogenetic dietary transition, suggesting that such changes might be related to an individual's ability to capture and consume larger, more elusive prey. The digestive tube is short and grows isometrically, which is in accordance with the carnivorous habit of this estuarine fish and its maintenance through ontogeny.

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Dissertação de Mestrado Integrado em Medicina Veterinária

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Background Some studies have reported a ceiling effect in EQ-5D-3L, especially in healthy and/or young individuals. Recently, two further levels have been included in its measurement model (EQ-5D-5L). The purposes of this study were (1) to assess the properties of the EQ-5D-5L in comparison with the standard EQ-5D-3L in a sample of young adults, (2) to foreground the importance of collecting qualitative data to confirm, validate or refine the EQ-5D questionnaire items and (3) to raise questions pertaining to the wording in these questionnaire items. Methods The data used came from a sample of respondents aged 30 or under (n = 624). They completed both versions of the EQ-5D, which were compared in terms of feasibility, level of inconsistency and ceiling effect. Agreement between the instruments was assessed using correlation coefficients and Bland-Altman plots. Known-groups validity of the EQ-5D-5L was also assessed using non-parametric tests. The discriminative properties were compared using receiver operating characteristic curves. Finally, four interviews were conducted for retrospective reports to elicit respondents’ understanding and perceptions of the format, instructions, items, and responses. Results Quantitative results show a ceiling effect reduction of 25.3 % and a high level agreement between both indices. Known-groups validity was confirmed for the EQ-5D-5L. Explorative interviews indicated ambiguity and low degree of certainty in regards to conceptualizing differences between levels moderate-slight across three dimensions. Conclusions The EQ-5D-5L performed better than the EQ-5D-3L. However, the explorative interviews demonstrated several limitations in the EQ-5D questionnaire wording and high context-dependent answers point to lack of illnesses’ experience amongst young adults.

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A comprehensive environmental monitoring program was conducted in the Ojo Guareña cave system (Spain), one of the longest cave systems in Europe, to assess the magnitude of the spatiotemporal changes in carbon dioxide gas (CO2) in the cave–soil–atmosphere profile. The key climate-driven processes involved in gas exchange, primarily gas diffusion and cave ventilation due to advective forces, were characterized. The spatial distributions of both processes were described through measurements of CO2 and its carbon isotopic signal (δ13C[CO2]) from exterior, soil and cave air samples analyzed by cavity ring-down spectroscopy (CRDS). The trigger mechanisms of air advection (temperature or air density differences or barometric imbalances) were controlled by continuous logging systems. Radon monitoring was also used to characterize the changing airflow that results in a predictable seasonal or daily pattern of CO2 concentrations and its carbon isotopic signal. Large daily oscillations of CO2 levels, ranging from 680 to 1900 ppm day−1 on average, were registered during the daily oscillations of the exterior air temperature around the cave air temperature. These daily variations in CO2 concentration were unobservable once the outside air temperature was continuously below the cave temperature and a prevailing advective-renewal of cave air was established, such that the daily-averaged concentrations of CO2 reached minimum values close to atmospheric background. The daily pulses of CO2 and other tracer gases such as radon (222Rn) were smoothed in the inner cave locations, where fluctuation of both gases was primarily correlated with medium-term changes in air pressure. A pooled analysis of these data provided evidence that atmospheric air that is inhaled into dynamically ventilated caves can then return to the lower troposphere as CO2-rich cave air.