Ultrastructural and cytochemical study on vitellogenesis in the diphyllidean cestode Echinobothrium euterpes (Echinobothriidae) and its phylogenetical implications

The first description of vitellogenesis in the Diphyllidea is presented in this paper. Though the type of vitellogenesis and mature vitellocyte in Echinobothriumeuterpesappear to be unique among the Eucestoda, however, they somewhat resemble that observed in the two orders of the lower cestodes, Tetraphyllidea and Proteocephalidea. Vitellocyte maturation is characterized by: (1) an increase in cell volume; (2) extensive development of short, parallel, frequently concentric cisternae of GER that produce dense proteinaceous granules; (3) development of Golgi complexes engaged in packaging this material; (4) progressive formation of saturated lipid droplets; their continuous enlargement and fusion; (5) formation of small accumulations of glycogen particles scattered between and among lipid droplets in the cytoplasm of maturing vitellocytes; (6) concentration of dense proteinaceous granules in the peripheral layer of cytoplasm, around the cell plasma membrane; and (7) vacuolization of cytoplasm of mature vitellocytes accompanied by a rapid increase in its volume. A new,unreported type of dense proteinaceous granules, situated around the limiting plasma membranes of mature vitellocytes, is described. Vitellogenesis evidently differs from that with typical shell-globules and shell-globule clusters previously reported in other taxa of lower cestodes. Cytochemical staining with periodic acidthiosemicarbazide-silver proteinate for glycogen indicates a strongly positive reaction for glycogen particles between and around largeunsaturated lipid droplets of the maturing and mature vitellocytes. Some hypotheses concerning the interrelationship between this pattern of vitellogenesis, possible mode of egg formation, embryonic development and diphyllidean life cycle, and their phylogenetic implications are drawn and discussed.publishe

Cascais: a nova Saint-Tropez dos Franceses

O presente estudo versa sobre os reformados franceses que residem em Cascais e praticam o Turismo Residencial através da aquisição de segundas residências. O objetivo do trabalho consiste em analisar os motivos que levaram os reformados franceses a migrar para a região de Cascais e adquirirem uma segunda residência; entender todo o processo de integração e instalação dos mesmos neste novo estilo de vida, e por último, apresentar um perfil do turista francês já reformado em Cascais. Para tal, a metodologia adotada para testar as hipóteses de investigação foi a realização de um case study (estudo de caso), através da técnica de recolha de informação bibliográfica, observação participada e realização de entrevistas semi-estruturadas direcionadas a um grupo de nove reformados franceses proprietários de segunda residência na Freguesia de Cascais e Estoril, bem como à Manager do Turismo Residencial da Associação do Turismo de Cascais. Os principais resultados obtidos através das várias técnicas utilizadas permitiram verificar que se tratam de reformados franceses com uma idade compreendida entre os 68 e os 70 anos, provenientes da zona Oeste e Centro de França, onde o principal motivo por que migraram para Cascais são as condições climatéricas, ao que caracterizam Cascais como um destino com qualidade de vida, tratando-se de indivíduos que se consideram úteis para a comunidade local, no qual se verifica uma integração positiva na comunidade local. Com o presente trabalho conclui-se que o principal motivo por que os reformados franceses migraram para Cascais foram as condições climatéricas, sendo que os mesmos estimulam o turismo residencial em Cascais, e nunca tiveram problemas de integração com a comunidade local. Porém, necessitam de viajar com regularidade entre o país emissor e o país recetor. Para os reformados franceses, Cascais é um lugar com um significado emocional, no qual imaginavam uma vida agradável no destino. Por fim, os reformados franceses aconselhariam Cascais como um destino para viver a amigos e familiares.The present study deals with French retirees who live in Cascais and practice Residential Tourism through the acquisition of second homes. The objective of this scientific work is to analyze the reasons why the French pensioners migrated to the region of Cascais and acquired a second residence; understand the whole process of integration and installation of the same in this new lifestyle, and lastly, present a profile of the retired French tourist resident living in Cascais. To that end, the methodology used to test the hypothesis of the present study was through the elaboration of a case study, using the technique of collecting bibliographical information, participant observation, and semi-structured interviews directed to a group of nine retired French owners of a second residence in the parish of Cascais and Estoril, as well as to the Manager of Residential Tourism of the Cascais Tourism Association. The main results obtained through the various techniques used allowed us to verify that they are French pensioners aged between 68 and 70 years, coming from the West and Center of France, where the main reason that led them to migrate to Cascais are the weather conditions, which characterize Cascais as a destination with quality of life, being individuals who consider themselves useful to the community, to which their integration into the community has been positive. With the present work it is concluded that the main reason why the French retirees migrated to Cascais were the climatic conditions, in which they stimulate residential tourism in Cascais, never having problems of integration. However, they need to travel regularly between the sending country and the recipient country. For French retirees, Cascais is a place with an emotional meaning, in which they imagined a pleasant life in the destination. Finally, the French pensioners would advise Cascais as a destination to live for friends and family

Trace element concentrations in Raillietina micracantha in comparison to its definitive host, the feral pigeon Columba livia in Santa Cruz de Tenerife (Canary Archipelago, Spain)

The use of systems involving bird parasites as bioindicators of environmental pollution has been scarcely studied in comparison to other models involving fish and rodent parasites, which have been demonstrated as particularly adequate due to their bioaccumulation capacities. The present study evaluated the accumulation of nine trace elements in the cestode Raillietina micracantha and in its host Columba livia collected from the densely populated city of Santa Cruz de Tenerife (Canary Islands, Spain). Samples (kidney, liver, pectoral muscle, feathers, and R. micracantha) of 27 infected C. livia were selected for trace element analysis by inductively coupled plasma-mass spectrometry. Element levels in pigeon tissues revealed some degree of pollution in Santa Cruz de Tenerife, particularly by Pb and Zn. Pb and Mn mean concentrations were higher in R. micracantha than in the pigeon's soft tissues, with subsequent high bioaccumulation factors for Pb (kidney = 15.38, liver = 10.38, muscle = 79.83) and Mn (kidney = 6.81, liver = 7.52, muscle = 19.89, feathers = 6.11), among others. The negative relations detected for As concentrations between liver and R. micracantha emphasize a possible role of the cestode in As detoxification in host tissues. Considering the obtained bioaccumulation factors, the system R. micracantha/C. livia is proposed as another promising bioindicator system to evaluate environmental toxic element exposure, particularly Pb and Mn, in areas where pollution levels are still relatively low and where both common species are present.publishe

Spermatological characters of Acanthobothrium crassicolle Wedl, 1855 (Tetraphyllidea, Onchobothriidae), a parasite of the common stingray Dasyatis pastinaca

We describe the spermiogenesis process and the ultrastructural characters of the spermatozoon of Acanthobothrium crassicolle by means of transmission electron microscopy, including cytochemical analysis for glycogen. Spermiogenesis in A.crassicolle begins with the formation of the differentiation zone that contains two centrioles associated with striated rootlets and an intercentriolar body. The latter is formed by one electron-dense layer. The centrioles develop into two free flagella that first grow orthogonally to a median cytoplasmic process and then undergo flagellar rotation becoming parallel to that median cytoplasmic process. After flagellar rotation only one of the flagella completes its growth and both short and long flagella undergo proximodistal fusion with the median cytoplasmic process. In the final stages of spermiogenesis, the nucleus becomes filiform and migrates into the spermatid body. Later, the ring of arched membranes constricts and the spermatozoon is liberated from the residual cytoplasm. The ultrastructural organization of the spermatozoon of A.crassicollefollows the general pattern of spermatozoa of the other Tetraphyllidea-Onchobothriidae species, but exhibits some differences. It is filiform, tapered at both extremities and lacks mitochondrion. It contains two axonemes of unequal length showing the 9 + “1” pattern of Trepaxonemata, a nucleus, parallel cortical microtubules and electron-dense granules of glycogen. The anterior extremity of the male gamete contains a single crested body surrounding a thin and long apical cone. This type of apical cone has never been described in a tetraphyllidean spermatozoon. Another particularity is the presence of a single electron-dense microtubule at the vertex of the crested body.publishe

Heavy metal accumulation by intestinal helminths of vertebrates

Podeu consultar el llibre complet a: http://hdl.handle.net/2445/32393The relevancy of parasites as potential indicators of environmental quality has been increasing over the last years, mostly due to the variety of ways in which they respond to anthropogenic pollution. The use of fish parasites as bioindicators of heavy metal pollution in aquatic ecosystems has been widely studied. However, little information concerning terrestrial habitats is presently available. In fact, in the last two decades several studies have been performed worldwide in different habitats and/or conditions (theoretically both in polluted and unpolluted terrestrial ecosystems, but mainly in aquatic ecosystems) in order to investigate heavy metal pollution using parasitological models. Different groups of vertebrates (mainly fish, mammals and birds) and several parasitological models have been tested involving acanthocephalans mostly, but also cestodes and nematodes. It is not the aim of this chapter to do a complete revision of the available data concerning this subject. Instead, we emphasize some general aspects and compile a mini-review of the work performed in this field by our research group. The results obtained until now allow confirming several parasitic models as promising bioindicator systems to evaluate environmental cadmium and mainly lead pollution in terrestrial non-urban habitats, as it was already demonstrated for aquatic ecosystems. The present knowledge also allows confirming that parasites can reveal environmental impact. Environmental parasitology is an interdisciplinary field, which needs simultaneous expertise from toxicology, environmental chemistry and parasitology. Furthermore, environmental parasitology should be taken into account in order to increase the efficiency of environmental monitoring programs

Plug-in Eclipse para geração automática de requisitos de teste

Tese de mestrado em Engenharia Informática (Engenharia de Software) Universidade de Lisboa, Faculdade de Ciências, 2020Produzir software com qualidade que satisfaça os requisitos funcionais é o objectivo principal da Engenharia de Software . Para fazer face a este desafio concorrem diversos fatores, entre os quais, o teste das aplicações. É, portanto, primordial dominar as técnicas adequadas de teste de software . O PESTT Educational Software Testing Tool (PESTT) é uma ferramenta que auxilia as actividades de desenho e de análise de cobertura de testes unitários baseados em grafos de controlo de fluxo (CFG). Esta ferramenta foi pensada para ser usada como apoio ao ensino dos conceitos e técnicas introdutórias de teste de software . O PESTT foi inicialmente desenvolvido em 2012 para integrar o Eclipse IDE 3.x, no âmbito da tese de mestrado do Rui Manuel da Silva Gameiro, orientado pelo Prof. Doutor Francisco Cipriano da Cunha Martins. Desde 2012, novas versões do Eclipse foram lançadas, estando atualmente na versão 4.11.2. Após o lançamento da 4ª versão do Eclipse, o funcionamento do PESTT foi comprometido. O principal objetivo desta tese é o de adaptar o PESTT para ficar em conformidade com as mudanças efetuadas do Eclipse 3.x para o Eclipse 4.x. Para tal, alterou-se significativamente o desenho do pacote da User Interface para tirar partido do novo MVC disponibilizado pelo Eclipse 4. O trabalho realizado no âmbito desta tese resultou naquilo que era desde cedo o nosso objetivo: voltar a disponibilizar o PESTT para as versões atuais do Eclipse, embora para um subconjunto das funcionalidades. As funcionalidades disponibilizadas nesta versão do plug-in cobrem a maioria dos aspetos que tornaram o PESTT uma ferramenta com valor suficiente para que este projeto tenha sido criado e desenvolvido. Neste documento são descritos os objetivos do projeto, a motivação e importância da sua concretização, o trabalho anteriormente feito e relacionado, as metodologias utilizadas, os resultados alcançados e possível trabalho futuro.The main goal of Software Engineering is to produce quality software that meets the functional requirements. Several factors contribute to achieve this challenge, including application testing. It is, therefore, paramount to appropriate master software testing techniques. The PESTT Educational Software Testing Tool (PESTT) is a tool that assists in the design and coverage analysis of unit tests based on control flow graphs (CFG). This tool is intended to assist in teaching the concepts and introductory techniques of software testing. PESTT was initially developed in 2012 to integrate the Eclipse IDE 3.x, within the context of the master's thesis of Rui Manuel da Silva Gameiro, supervised by Prof. Doctor Francisco Cipriano da Cunha Martins. Since 2012, new versions of Eclipse have been released and are currently in the 2019-09 version (4.11.2). After the release of Eclipse 4th version, it was found that PESTT execution was compromised. The main purpose of this thesis is to adapt PESTT to conform to changes made from Eclipse 3.x to Eclipse 4.x. For that, the design of the user interface packethas significantly changed to take advantage of the new MVC provided by Eclipse 4.The work carried out under this thesis fulfilled our main goal: to make PESTTavailable again for the current versions Eclipse, although some functionalities were leftoutside. The features provided in this version of the plug-in cover most aspects that have made PESTT a valuable tool for the creation and execution of this project.This document describes the objectives of the project, the motivation and importance of its implementation, the related and previously done work, the used methodologies, the achieved results, and possible future work

Perch and its parasites as heavy metal biomonitors in a freshwater environment: the case study of the Ružín water reservoir, Slovakia

Heavy metal concentrations were determined in 43 perches (Perca fluviatilis) and in two of its most common parasites, the acanthocephalan Acanthocephalus lucii and the cestode Proteocephalus percae, collected in the period 2009-2010 from Ružín, a seriously polluted water reservoir in Slovakia. Samples of muscle, liver, kidney, brain, male and female reproductive organs and adipose tissue of fish and both parasites were analyzed for As, Cd, Cr, Cu, Hg, Mn, Ni, Pb and Zn, by ICP-MS. Mean concentrations of individual heavy metals in all fish samples decreased in the order zinc > copper > manganese > mercury > arsenic > chromium > cadmium > nickel > lead. Zinc was found to be the dominant element and its antagonistic interaction with copper was confirmed. The kidney was a key target organ receiving the highest mean concentrations of all analyzed metals, but some metals showed specific affinity for particular tissues. In terms of human health, concentration of Hg in fish muscle, which exceeded more than two-times its maximum level admitted in foodstuffs in European countries, is of great importance and should be taken into account. Bioaccumulation factors s (C[parasite]/C[fish tissue]) calculated for all elements indicated much higher detection skills of A. lucii and P. percae parasites than fish organs and hence, present results allow proposing both parasite models as useful tools to monitor aquatic environmental quality. Acanthocephalans, however, seem to be superior for heavy metal monitoring, also demonstrated under experimental conditions. Present results also indicate the decreasing heavy metal burden of the reservoir and its gradual recovery in the course of time.publishe

Balearic shearwater and northern gannet bycatch risk assessment in Portuguese Continental Waters

Even though incidental captures in fisheries are one of the major threats to seabirds, bycatch has been difficult to quantify and specific risk areas are rarely identified. The present study evaluates the potential fisheries bycatch effect on two of the most emblematic seabird species wintering off continental Portugal, the critically endangered Balearic Shearwater and Northern Gannet. Information was collected by on-board observers and voluntary logbooks kept by fishing boat captains. Each species' Potential Biological Removal (for the study area) was based on the respective population abundance estimated through aerial surveys. The analysis of bycatch mortality identified the Fixed Gear in the Polyvalent fleet and Purse Seiners as the fisheries with the highest Balearic Shearwater bycatch rate. Longline and Fixed Gear fisheries had the highest Northern Gannet bycatch rate. The Potential Biological Removal thresholds were 41 Balearic Shearwaters per year (CI ¼ 20–83) and 2345 Northern Gannets per year (CI ¼ 2049–2680). The overlap between the predictive species distribution maps and fisheries density maps allowed for a seabird Bycatch Risk Assessment. The higher Balearic Shearwater bycatch risk was obtained for Fixed Gear and Purse Seines and the highest Northern Gannet bycatch risk was obtained for Longline and Fixed Gear fisheries. Bycatch mitigation measures should be applied in fisheries presenting the higher bycatch risks. This study identifies the potential areas where Balearic Shearwater and Northern Gannet bycatch is more likely to occur, including some of the already designated Special Protection Areas where management and conservation measures should urgently be applied.info:eu-repo/semantics/publishedVersio

Ultrastructure of the spermatozoon of the trematode Notocotylus noyeri (Digenea: Notocotylidae), a parasite of Microtus arvalis (Rodentia: Cricetidae)

In the present paper, we describe the ultrastructure of the spermatozoon of the notocotylid Notocotylus noyeri (Joyeux, 1922) by means of transmission electron microscopy. The mature spermatozoon of N. noyeri exhibits the general pattern described in the majority of digeneans: two axonemes of the 9 + "1" pattern of the Trepaxonemata, nucleus, mitochondria, parallel cortical microtubules, spine-like bodies and ornamentation of the plasma membrane. The glycogenic nature of the electron-dense granules was evidenced applying the test of Thiéry. The ultrastructural features of the spermatozoon of N. noyeri present some differences in relation to those of the Pronocephalidea described until now, but confirm a general pattern for the Notocotylidae, namely a spermatozoon with two mitochondria and an anterior region with ornamentation of the plasma membrane associated with spine-like bodies. The posterior extremity of the spermatozoon exhibits only some microtubules after the disorganisation of the second axoneme. The present study confirms that some ultrastructural characters of the sperm cell such as the presence or absence of lateral expansions, the number of mitochondria and the morphology of both anterior and posterior spermatozoon extremities are useful for phylogenetic purposes within the Pronocephaloidea. Thus, unlike notocotylids, pronocephalids exhibit external ornamentation and a lateral expansion in the anterior spermatozoon region. Moreover, notocotylid spermatozoa present two mitochondria, whereas pronocephalid spermatozoa exhibit a single mitochondrion. Finally, pronocephalids are characterised by a type 2 posterior spermatozoon extremity, whereas notocotylids exhibit a type 3 posterior spermatozoon extremit

Effect of external tooth bleaching on the surface of resin composites – An in vitro study

AbstractObjectivesTo evaluate the effects of external tooth whitening on the surface of two types of resin composites, by scanning electron microscopy (SEM).MethodsEighteen (N=18) specimens were assigned into six groups using two composites: a nanohybrid (Tetric EvoCeram®) and a nanofill (Filtek Supreme XT®); and three protocols: 10% carbamide peroxide (CP) whitening (TW10 and FW10); 22% CP whitening (TW22 and FW22); control group (TC and FC). For each group, the resin composite was introduced into a silicon mold and light-cured according to manufacturer's instructions. Specimens were stored in distilled water (37°C, 24h), polished, and then randomly divided into the mentioned groups. Specimens from the whitening groups were exposed to the CP gels (White Dental Beauty®) for 6h per day. TC and FC specimens were exposed to distilled water. All specimens were stored in an incubator (37°C, 14 days) and observed by SEM. It was measured the hydrogenionic potential (pH) of the CP gels.ResultsSEM analysis of both composites exposed to the CP gels showed surface changes, namely superficial cracks and numerous porous, highlighting a real separation between the resin matrix and the composite fillers, regardless of the gel concentration. These changes were more notorious in the nanohybrid composite. 10% and 22% CP gels have a pH value of 6.71 and 7.42, respectively.ConclusionThe 10% and 22% CP led to changes on both surface composites. These alterations are pronounced in the nanohybrid composite and are independent of the concentrations used