330 resultados para Shores.


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Publiées dans la Collection des prospects durant la guerre d’Indépendance américaine, les vues d’optique Vuë de la Place capitale dans la Ville basse a Quebec, Vuë de la haute ville a Quebeck, Vuë de la basse Ville a Quebec vers le fleuve St-Laurent, Vuë de la rue des recolets de Quebeck et Vuë de Quebeck gravées par les Allemands Franz Xaver Habermann (1721-1796) et Balthasar Frederich Leizelt (1755-1812) entretiennent des liens ténus avec la configuration réelle de la ville de Québec qu’elles représentent. L’escamotage du paradigme documentaire dans ces images est l’enjeu principal de ce mémoire. Il permet de mettre l’accent sur les contraintes formelles découlant du dispositif optique de lecture utilisé ainsi que sur les modèles culturels concernant la perception du territoire urbain américain ayant prévalu lors de la création et de la réception des cinq vues d’optique à l’étude. L’analyse de la vision fictionnelle du paysage donnera également des indices sur les orientations idéologiques et l’imaginaire du lieu, perçu comme un ailleurs lointain, par un ensemble politique qui n’exerce pas de domination directe sur la colonie installée sur le bord du fleuve Saint-Laurent.

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Boloceroides spp. are looking like an untidy mop, this anemone is sometimes seen in sea grass areas on many of our shores. It is possibly seasonal. Sometimes, large numbers are seen (up to 10-20 animals in a trip) and then none at all.  Tiny swimming anemones may sometimes be confused with Sea grass anemones which have translucent tentacles with tiny spots. The swimming anemone harbors symbiotic single-celled algae (zooxanthellae). The algae undergo photosynthesis to produce food from sunlight. The food produced is shared with the sea anemone, which in return provides the algae with shelter and minerals. The oral disk and tentacle muscles are used to obtain, retain, and ingest prey; in Boloceroides spp. tentacles can autotomize if it is needed to evade a predator. Tentacles can control body form by use of their endodermal muscles. Retractors are longitudinal muscles that will aid in withdrawing tentacles and the oral disk if they are exposed to the open air.  This hypothesis is furthered because in comparison to other sea anemones, Boloceroides is loosely attached to its respective substrate, thus allowing the pedal disk to detach quickly resulting in a rapid swimming response. Boloceroides can reproduce both sexually and asexually. As Anthozoans, Boloceroides produce sexually by bypassing the medusa life cycle stage; this allows Boloceroides (and all Anthozoans) to release their egg and sperm creating planula a bilaterally symmetrical, flattened, ciliated, motile larva.

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The coastal zone of the Nord – Pas de Calais / Picardie showed dysfonctioning patterns of the ecosystem considered to be link to human activities along shores. These results in regular massive development of species, such as the phytoplanktonic seaweed, Phaeocystis sp. which life cycle was partly linked to nutrients availability and consequently to anthropogenic inputs. As part of the evaluation of the influence of continental inputs on the marine environment (nitrates, phosphates,…) and on potential eutrophication processes, of the estimation of the efficiency of the sewage treatments plants in the possible elimination of dumpings and in order to establish a long-term survey to follow up the change in coastal waters quality, the regional nutrients monitoring network was implemented by Ifremer in collaboration with the Agence de l'Eau Artois-Picardie in 1992 in order to complete the REPHY (Phytoplankton and Phycotoxins) monitoring programme. This study reports the main results for the year 2015 in terms of temporal change of the main physico-chemical and biological parameters characteristic of water masses sampled along three transects offshore Dunkerque, Boulogne-sur-Mer and the Bay of Somme.

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Aim Description of pathologic causes of cervical lymphadenopathy at Kamuzu Central Hospital. Introduction The evaluation of cervical lymphadenopathy is a common diagnostic challenge facing clinicians. Previously at Kamuzu Central Hospital (KCH) tuberculosis (TB) was reported to be the most common cause of cervical lymphadenopathy However, no recent study has assessed this common diagnostic challenge in Malawi, particularly since the beginning of the HIV epidemic and the subsequent scale-up of antiretroviral therapy. Methods We conducted a cross-sectional study of all cervical lymph node specimens from the KCH pathology laboratory between 1 July 2011 and 28 February 2013 and describe patient age, gender, and pathologic diagnoses. Results Our search of the KCH pathology database yielded 179 cases. Of these, 143 (77%) were histologic specimens (open biopsy or core needle samples) while 34 (23%) were cytology specimens. The age range was from 0 to 76 years with a mean of 30 (SD: 19). In adults, the most common diagnosis was malignancy (n=41, 35%), while in children 15 cases each of malignancy and benign masses were diagnosed. Only 6 cases (5%) of TB were diagnosed in adults, and 4 cases (6%) of TB were diagnosed in children. Conclusion Our study shows more malignancy and much less TB than a prior study of cervical lymphadenopathy at KCH. With the successful initiaion of the KCH Pathology Laboratory in 2011, we recommend biopsy or FNA early in the workup of cervical lymphadenopathy to prevent long delays in diagnosis and treatment of curable cancers.

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Aim Review the literature from 1990 to 2013 to determine known anatomic sites, risk factors, treatments, and outcomes of head and neck squamous cell carcinoma (HNSCC) in sub-Saharan Africa. Methods Using a systematic search strategy, literature pertaining to HNSCC in sub-Saharan Africa was reviewed and patient demographics, anatomic sites, histology, stage, treatment, and outcomes were abstracted. The contributions of human immunodeficiency virus (HIV), human papillomavirus (HPV) and behavioural risk factors to HNSCC in the region were assessed. Results Of the 342 papers identified, 46 were utilized for review, including 8611 patients. In sub-Saharan Africa, the oropharyngeal/oral cavity was found to be the most common site, with 7750 cases (90% of all cases). Few papers distinguished oropharyngeal from oral cavity, making identification of possible HPV-associated oropharyngeal squamous cell carcinoma (SCC) difficult. SCC of the nasopharynx, nasal cavity, or paranasal sinuses was identified in 410 patients (4.8% of all cases). Laryngeal SCC was found in 385 patients (4.5% of all cases), and only 66 patients (0.8% of all cases) with hypopharyngeal SCC were identified. In 862 patients with data available, 43% used tobacco and 42% used alcohol, and reported use varied widely and was more common in laryngeal SCC than that of the oropharyngeal/oral cavity. Toombak and kola nut use was reported to be higher in patients with HNSCC. Several papers reported HIV-positive patients with HNSCC, but it was not possible to determine HNSCC prevalence in HIV-positive compared to negative patients. Reports of treatment and outcomes were rare. Conclusions The oropharyngeal/oral cavity was by far the most commonly reported site of HNSCC reported in sub-Saharan Africa. The roles of risk factors in HNSCC incidence in sub-Saharan Africa were difficult to delineate from the available studies, but a majority of patients did not use tobacco and alcohol.

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Aim There is a high burden of oesophageal cancer in Malawi with dismal outcomes. It is not known whether environmental factors are associated with oesophageal cancer. Without knowing this critical information, prevention interventions are not possible. The purpose of this analysis was to explore environmental factors associated with oesophageal cancer in the Malawian context. Methods A hospital-based case-control study of the association between environmental risk factors and oesophageal cancer was conducted at Kamuzu Central Hospital in Lilongwe, Malawi and Queen Elizabeth Central Hospital in Blantyre, Malawi. Ninety-six persons with squamous cell carcinoma and 180 controls were enrolled and analyzed. These two groups were compared for a range of environmental risk factors, using logistic regression models. Unadjusted and adjusted odds ratios and 95% confidence intervals (CI) were calculated. Results Firewood cooking, cigarette smoking, and use of white maize flour all had strong associations with squamous cell carcinoma of the oesophagus, with adjusted odds ratios of 12.6 (95% CI: 4.2-37.7), 5.4 (95% CI: 2.0-15.2) and 6.6 (95% CI: 2.3-19.3), respectively. Conclusions Several modifiable risk factors were found to be strongly associated with squamous cell carcinoma. Research is needed to confirm these associations and then determine how to intervene on these modifiable risk factors in the Malawian context.

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Available information on the larval release rhythms of brachyurans is biased to temperate estuarine species and outcomes resulting from some sort of artificial manipulation of ovigerous females. In this study we applied field methods to describe the larval release rhythms of an assemblage of tropical rocky shore crabs. Sampling the broods of ovigerous females of Pachygrapsus transversus at two different shores indicated a spatially consistent semilunar pattern, with larval release maxima around the full and new moon. Yet, synchronism between populations varied considerably, with the pattern obtained at the site exposed to a lower wave action far more apparent. Breeding cohorts at one of the sampled shores apparently belonged to actual age groups composing the ovigerous population. The data suggest that these breeding groups release their larvae in alternate syzygy periods, responding to a lunar cycle instead of the semilunar pattern observed for the whole population. For the description of shorter-term rhythms, temporal series at hour intervals were obtained by sampling the plankton and confinement boxes where ovigerous females were held. Unexpectedly, diurnal release activity prevailed over nocturnal hatching. Yet, only grapsids living higher on the shore exhibited strong preferences over the diel cycle, with P. transversus releasing their larvae during the day and Geograpsus lividus during the night. The pea crab Dissodactylus crinitichelis, the spider crab Epialtus brasiliensis and a suite of xanthoids undertook considerable releasing activity in both periods. Apart from the commensal pea crab D. crinitichelis, all other taxa revealed tide-related rhythms of larval release, with average estimates of the time of maximum hatching always around the time of high tides; usually during the flooding and slack, rather than the ebbing tide. Data obtained for P. transversus females held in confinement boxes indicated that early larval release is mostly due to nocturnal hatching, while zoeal release in diurnal groups took place at the time of high tide. Since nocturnal high tides at the study area occurred late, sometimes close to dusk, early release would allow more time for offshore transport of larvae when the action of potential predators is reduced.

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Benthic marine invertebrates may form metapopulations connected via propagule dispersal. Conservation efforts often target potential source coastlines to indirectly benefit areas depending on allochthonous offspring production. Besides population density, adult size structure, sex ratio, brooding frequency and the proportion of breeding individuals may significantly influence the reproductive output of benthic populations, but these effects have seldom been tested. We used rocky shore crabs to assess the spatial variability of such parameters at relevant scales for conservation purposes and to test their consistency over 2 consecutive years; we then used the data to address whether bottom-up processes or biological interactions might explain the patterns observed. We decomposed egg production rates into their components for the 2 most abundant brachyuran species inhabiting the intertidal rocky habitat. Adult density and brooding frequency varied consistently among shores for both species and largely explained the overall spatial trends of egg production. Temporally consistent patterns also included among-shore differences in the size of ovigerous females of the grapsid Pachygrapsus transversus and between-bay differences in the fecundity of the spider crab Epialtus brasiliensis. Sex ratio was remarkably constant in both. We found no positive or negative correlations between adult density and brooding frequency to support either the existence of a component Allee effect (lack of mate encounters) or an effect of intra-specific competition. Likewise, shore-specific potential growth in P. transversus does not negatively correlate with frequency of ovigerous individuals, as would be expected under a critical balance between these 2 processes. The patterns observed suggest that bottom-up drivers may best explain spatial trends in the reproductive output of these species.

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Behaviours related to foraging and feeding in predator-prey systems are fundamental to our understanding of food webs. From the perspective of a predator, the selection of prey size depends upon a number of factors including prey vulnerability, prey size, and the predator's motivation to eat. Thus, feeding motivation and prey visual cues are supposed to influence predator decisions and it is predicted that prey selection by visual cues is modulated by the predator's stomach fullness prior to attacking a prey. This study was conducted using an animal model from the rocky shores ecosystem, a predatory fish, the frillfin goby Bathygobius soporator, and a benthic prey, the mottled shore crab Pachygrapsus transversus. Our results demonstrate that frillfin gables are capable of visually evaluating prey size and that the size evaluation process is modulated by the level of stomach fullness. Predators with an empty stomach (0% fullness) attacked prey that was larger than the predicted optimal size. Partially satiated predators (50% stomach fullness) selected prey close to the optimal size, while fully satiated predators (100% stomach fullness) showed no preference for size. This finding indicates an integrative response of the predator that depends on the input of both internal and external sensory information when choosing prey. Predator perceptions of visual cues (prey size) and stomach fullness modulate foraging decisions. As a result, a flexible feeding behaviour emerges, evidencing a clearly adaptive response in line with optimal foraging theory predictions. (C) 2012 Elsevier GmbH. All rights reserved.

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Tese (doutorado)—Universidade de Brasília, Faculdade de Arquitetura e Urbanismo, Programa de Pesquisa e Pós-Graduação da Faculdade de Arquitetura e Urbanismo, 2016.

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We present a checklist of the shores fishes of the coast of the Rio Grande do Norte state. Species were registered through the specimens collection, underwater records, samples in landings of artisanal fleet and by compilation of data from literature and ichthyologic collections, between January 2004 to 2006. A total of 440 species form 2 classes, 25 orders, 106 families and 253 genus were registered. It is believed that due the great increase of the number of species registered, the ichthyofauna of the coast of this state is reasonably known

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The anisotropy of the Biscayne Aquifer which serves as the source of potable water for Miami-Dade County was investigated by applying geophysical methods. Electrical resistivity imaging, self potential and ground penetration radar techniques were employed in both regional and site specific studies. In the regional study, electrical anisotropy and resistivity variation with depth were investigated with azimuthal square array measurements at 13 sites. The observed coefficient of electrical anisotropy ranged from 1.01 to 1.36. The general direction of measured anisotropy is uniform for most sites and trends W-E or SE-NW irrespective of depth. Measured electrical properties were used to estimate anisotropic component of the secondary porosity and hydraulic anisotropy which ranged from 1 to 11% and 1.18 to 2.83 respectively. 1-D sounding analysis was used to models the variation of formation resistivity with depth. Resistivities decreased from NW (close to the margins of the everglades) to SE on the shores of Biscayne Bay. Porosity calculated from Archie's law, ranged from 18 to 61% with higher values found along the ridge. Higher anisotropy, porosities and hydraulic conductivities were on the Atlantic Coastal Ridge and lower values at low lying areas west of the ridge. The cause of higher anisotropy and porosity is attributed to higher dissolution rates of the oolitic facies of the Miami Formation composing the ridge. The direction of minimum resistivity from this study is similar to the predevelopment groundwater flow direction indicated in published modeling studies. Detailed investigations were carried out to evaluate higher anisotropy at West Perrine Park located on the ridge and Snapper Creek Municipal well field where the anisotropy trend changes with depth. The higher anisotropy is attributed to the presence of solution cavities oriented in the E-SE direction on the ridge. Similarly, the change in hydraulic anisotropy at the well field might be related to solution cavities, the surface canal and groundwater extraction wells.

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This thesis offers an examination of egg-collecting, which was a very popular pastime in Britain from the Victorian era well into the twentieth century. Collectors, both young and old, would often spend whole days and sometimes longer trips in a wide variety of different habitats, from sea shores to moorlands, wetlands to craggy mountainsides, searching for birds’ nests and the bounty to be found within them. Once collectors had found and taken eggs, they emptied out the contents; hence, they were really eggshell collectors. Some egg collectors claimed that egg-collecting was not just a hobby but a science, going by the name of oology, and seeking to establish oology as a recognised sub-discipline of ornithology, these collectors or oologists established formal institutions such as associations and societies, attended meetings where they exhibited unusual finds, and also contributed to specialist publications dedicated to oology. Egg-collecting was therefore many things at once: a culture of the British countryside, from where many eggs were taken; a culture of natural history, taking on the trappings of a science; and a culture of enthusiasm, providing a consuming passion for many collectors. By the early twentieth century, however, opposing voices were increasingly being raised, by conservation groups and other observers, about the impact that egg-collecting was having on bird populations and on the welfare of individual birds. By mid-century the tide had turned against the collectors, and egg-collecting in Britain was largely outlawed in 1954, with further restrictions imposed in 1981. While many egg collections have been lost or destroyed, some have been donated to museums, including Glasgow Museums (GM), which holds in its collections over 30,000 eggs. As a Collaborative Doctoral Award involving the University of Glasgow and GM, the project outlined in this thesis aims to bring to light and to life these egg collections, the activities of the collectors who originally built them, and the wider world of British egg-collecting. By researching archival material held by Glasgow Museums, published specialist egg-collecting journals and other published sources, as well as the eggs as a material archive, this thesis seeks to recover some of the practices and preoccupations of egg collectors. It also recounts the practical activities carried out during the course of the project at GM, particularly those involving a collection of eggs newly donated to the museum during the course of this project, culminating in a new temporary display of birds’ eggs at Glasgow Museums Resource Centre.

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This thesis contributes to the knowledge of temperate rocky shore ecology, with direct implications in the management and conservation of two important local marine resources that inhabit the very edge of subtidal and intertidal habitats on wave-swept rocky shores: the sessile filter feeding stalked barnacle Pollicipes pollicipes and the mobile keystone herbivore sea urchin Paracentrotus lividus. Research was conducted along gradients of wave exposure on rocky shores of Southern Europe. The abundance of P. lividus was four times higher in SW Portugal than in NW Italy. Most of the variation in urchin abundance occurred at small spatial scales, probably shaped by habitat complexity. In SW Portugal, sea urchin attachment forces while in burrows were measured and related to burrow shape, urchin size and habitat. Burrowing behaviour enhances sea urchin attachment force and might be an adaptive response to hydrodynamic stress. Abundance of P. pollicipes in SW Portugal is highly and positively related to wave exposure at local and regional scales. Predation and recruitment processes seem to be important drivers of these abundance patterns. A distribution model of P. pollicipes abundance in relation to wave exposure was developed for the SW coast of Portugal and might be used for improvement of its management and conservation. Growth of P. pollicipes was studied by applying a novel method using fluorescent calcein for marking and to estimate growth. Growth rate decreased with barnacle size and was highly variable amongst individuals, particularly in smaller barnacles. No effect of shore level on barnacle growth was detected. An assessment of the state of the fishery, conservation and management of the stalked barnacle in different regions of continental Portugal was made, highlighting an overall negative tendency of this state and recommending a change into a co-management system; Resumo: Viver no limite intertidal / subtidal: ecologia do percebe Pollicipes pollicipes e do ouriço-do-mar Paracentrotus lividus Esta tese contribui para o conhecimento da ecologia do litoral rochoso e tem implicações diretas na gestão e conservação de dois recursos marinhos locais que habitam o interface subtidal/intertidal de costas rochosas sujeitas a agitação marinha: o percebe Pollicipes pollicipes, animal séssil e filtrador e o ouriço-do-mar Paracentrotus lividus, animal móvel e herbívoro. Foram realizados vários estudos ao longo de gradientes de hidrodinamismo em costas rochosas do sul da Europa. A abundância de P. lividus foi quatro vezes superior no sudoeste de Portugal relativamente ao noroeste de Itália. Grande parte da variação na abundância de P. lividus ocorreu a pequenas escalas espaciais, provavelmente influenciada pela complexidade do habitat. A força com que o ouriço-do-mar se fixa ao substrato foi medida no terreno no sudoeste de Portugal, tendo esta sido relacionada com a forma da depressão que ocupa, o tamanho individual e o habitat. O comportamento escavador desta espécie aumenta a sua força de fixação ao substrato e poderá ser uma resposta adaptativa ao hidrodinamismo.. A abundância de P. pollicipes na costa sudoeste de Portugal, a diferentes escalas espaciais, está relacionada de forma positiva com a agitação marinha, e é influenciada pela predação e pelo recrutamento desta espécie. Foi desenvolvido um modelo de distribuição e abundância de P. pollicipes para esta costa baseado na relação com a agitação marinha, cujos resultados podem ser usados para melhorar a gestão e conservação deste recurso. Um novo método com recurso a calceina fluorescente foi desenvolvido para marcar percebes e estudar o seu crescimento. A taxa de crescimento diminuiu com o tamanho do animal, sendo altamente variável entre indivíduos, sobretudos nos de menores dimensões. O estado da apanha, conservação e gestão do percebe em diferentes regiões de Portugal Continental apresentou uma tendência global negativa, e recomenda-se uma alteração para um sistema de cogestão deste recurso.