998 resultados para Ships -- Ontario -- Niagara Peninsula -- History.


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Ce mémoire propose d’étudier les conditions et les perspectives des regroupements d’artistes autogérés face aux changements provoqués par la digitalisation des facteurs de production et de diffusion. L’analyse portée sur l’évolution de ces structures est illustrée par quatre cas spécifiques : le Vidéographe et la Coop Vidéo à Montréal et le Liaison of Independent Filmmakers of Toronto et V-Tape à Toronto. D’un historique de ces organismes, au contexte social et à la pratique artistique liés à leur émergence dans les années 70, cette étude tente de mettre en lumière les transformations de ces structures par l’apparition du médium numérique et d’Internet au tournant du siècle. La recherche s’appuie ici sur une étude approfondie des archives de ces groupes, d’entretiens avec les principaux acteurs concernés et des rapports gouvernementaux permettant de faire ressortir les problématiques actuelles de ces structures autogérées et d’amorcer des réflexions autour de leur pérennité.

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The Holocene vegetation history of the Arabian Peninsula is poorly understood, with few palaeobotanical studies to date. At Awafi, Ras al-Khaimah, UAE, a 3.3 m lake sediment sequence records the vegetation development for the period 8500 cal. yr BP to similar to3000 cal. yr BP. delta(13)C isotope, pollen and phytolith analyses indicate that C3 Pooid grassland with a strong woody element existed during the early Holocene (between 8500 and 6000 cal. yr BP) and became replaced by mixed C3 and C4 grasses with a strong C4 Panicoid tall grass element between 5900 and 5400 cal. yr BP. An intense, arid event Occurred at 4100 cal. yr BP when the lake desiccated and was infilled by Aeolian sand. From 4100 cal. yr BP the vegetation was dominated by C4 Chloridoid types and Cyperaceae, suggesting an incomplete vegetation cover and Aeolian dune reactivation owing to increased regional aridity. These data outline the ecosystem dynamics and carbon cycling in response to palaeomon-soon and north-westerly variability during the Holocene. Copyright (C) 2004 John Wiley Sons, Ltd.

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Richard Fung, a Toronto-based video artist and cultural critic, was born in Trinidad in 1954, and attended school in Ireland before immigrating to Canada to study at the University of Toronto. Richard Fung has taught at the Ontario College of Art and Design, and has been a visiting professor in the Department of Media Study at the State University of New York in Buffalo. He is currently the coordinator of the Centre for Media and Culture in Education, Ontario Institute for Studies in Education, University of Toronto.

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Aim: The aim of this thesis is to describe the process by which the inherited disease, cystic fibrosis, (CF) was recognised as an important clinical entity in the United Arab Emirates (UAE) and the Sultanate of Oman (Oman). It examines the clinical presentation of the first patients and assesses their degree of severity. Further, it describes the first studies carried out to determine the underlying CF mutations associated with the disease in the UAE and Oman. An estimate is offered of the birth frequency of the condition. Overall, the cultural, geographical and historical aspect of the societies in which the disease occurs is stressed. Methods: An initial literature search was carried out using Medline of any literature pertaining to the Arab World and CF. this was read and classified into the relevance to Arabs in general, the Middle East and then specifically the Arab (Persian) Gulf societies. Thereafter, a clinic was established at Tawam Hospital, Al Ain, UAE, for children presenting With chronic respiratory disease that could serve as a national referral centre. It was run by the Author as a service of the Paediatric Department of the UAE University Medical School. I sent a letter to every Paediatrician working in the UAE informing them of our clinic and offering our services for the diagnosis and management of chronic respiratory disease in children. This was based on the author's experience as a respiratory paediatrician in Australia and New Zealand and as the Professor of Paediatrics in the UAE. No such service then existed in the UAE. Funding was sought to establish a research programme and develop a molecular genetics laboratory in the UAE Medical School. A series of successful research applications provided the grants to commence the investigations. Once a small number of children had been identified as having CF from those referred to the respiratory clinic, the initial project was to assess and report their clinical presentation. Following this an early start was made on the identification of the mutations responsible. Once these were established an attempt was made to estimate the frequency of the condition at birth. Additional clinical studies revolved around assessing the severity of the condition that was associated with the main mutations that were identified. A clinical comparison was made with those with the mutation AF508 and the other main mutation, despite the obvious limitation of small numbers then available. Radiological assessment was made to evaluate the progression of the disease. The final aspect of the study was to assess patients from Oman and compare their findings and mutations with the neighbouring UAE. Based on information gained hypotheses are proposed regarding the spread of the gene mutation by population drift. Thesis outline: A literature review is presented in the form of a critique on the disease and a resume of the relevant aspects of the genetics of CF. Additionally, facts about the two countries' geography and history are presented. Finally, knowledge about CF mutations and population origins from other areas is presented. The second main section deals with the clinical features of the disorder as it presents in the UAE. Molecular findings are then presented and details of the common mutation found in Bedouin Arabs. Hypotheses are then presented based on the information gathered. Results: CF is not a rare disease in the Arab children of the UAE and Oman. These findings refute previous reports of CF being a rare or non-existent disease in Arabs. The condition presents with a severe clinical picture, with early colonisation of the respiratory tract with staphylococcus, haemophilus and pseudomonas organisms, even with conventional CF management practices in place. The CF mutation S549R is prevalent in Arabs of Bedouin stock, while AF508 is found in those of Baluch origin. The former may be descendants of Arabs who left southern Arabia and travelled to the Trucial Coast at the time of the destruction of the great dam at Marib. The origins of this mutation may lie in the area that corresponds to the modern Republic of Yemen. The latter groups are descendants of those who came originally from Baluchistan. It is hypothesised also that the ancestral home of the AF508 mutation may be in the geographical area now known as Baluchistan, that spans three separate modern political territories. The evidence presented supports the concept that the S549R mutation may be associated with a severe, if not the severest, clinical pattern recognised. It equates with that seen with the homozygous AF508 genotype. The absence of an additional mutation in the promoter region accounts for the different clinical pattern seen in previously described patients. Conclusions: There needs to be a major awareness of the presence of CF as a severe clinical disease in the children of the Gulf States. The clinical presentation and findings support the concept of under recognition of the disease. Climatic conditions put the children at special risk of hyponatraemia and electrolyte imbalance. The absence of surviving adults with the disease suggests premature deaths have occurred, but the high fertility rates have maintained the gene pool for this recessive disorder.

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This study investigates the benefits of using oral history as a tool for the sustainable management of estuaries. Twenty-two semi-structured interviews were conducted to generate oral history records for the Balcombe Estuary Reserve, a small estuary in a periurban zone on the Mornington Peninsula, Victoria. These interviews establish a more complete picture of changes in land use and ecological change to the estuary since European settlement of the area, and document community values. The interviews were followed with a survey to further explore management issues in the area. Use of oral history was found to be an effective approach to assist holistic estuarine management, especially when complemented by other sources of information.

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This paper examines the “Respect for History” project on Turkey's Gallipoli Peninsula sponsored by a Turkish oil company, OPET. The project sought to enhance and protect the cultural and historical experiences of tourists visiting Gallipoli, and to bring direct and indirect benefits to local communities through enhancing tourism-related business opportunities and improving community infrastructure. This research investigates the project's impact on residents’ perceived social and economic wellbeing, using a quality of life framework, and also ascertains residents’ views of the sponsoring firm. The context illustrates key differences between pure philanthropy and strategic philanthropy; the latter defined as doing good by purposefully achieving corporate and civic benefits. The role of strategic philanthropy as a sustainable tourism development tool, and its impact on tourism governance, are considered. Data were collected from 674 residents on the Turkish Gallipoli Peninsula in areas impacted by OPET's investment program. The results, using structural equation modelling (SEM), identify that respondents generally believe that both their economic and social quality of life have improved. This, in turn, has positively influenced respondents’ views of the sponsoring organization. The concept of strategic philanthropy appears valuable as a private sector, non-tourism, sustainable tourism development tool in some circumstances.

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BACKGROUND: Aloe vera supports a substantial global trade yet its wild origins, and explanations for its popularity over 500 related Aloe species in one of the world's largest succulent groups, have remained uncertain. We developed an explicit phylogenetic framework to explore links between the rich traditions of medicinal use and leaf succulence in aloes. RESULTS: The phylogenetic hypothesis clarifies the origins of Aloe vera to the Arabian Peninsula at the northernmost limits of the range for aloes. The genus Aloe originated in southern Africa ~16 million years ago and underwent two major radiations driven by different speciation processes, giving rise to the extraordinary diversity known today. Large, succulent leaves typical of medicinal aloes arose during the most recent diversification ~10 million years ago and are strongly correlated to the phylogeny and to the likelihood of a species being used for medicine. A significant, albeit weak, phylogenetic signal is evident in the medicinal uses of aloes, suggesting that the properties for which they are valued do not occur randomly across the branches of the phylogenetic tree. CONCLUSIONS: Phylogenetic investigation of plant use and leaf succulence among aloes has yielded new explanations for the extraordinary market dominance of Aloe vera. The industry preference for Aloe vera appears to be due to its proximity to important historic trade routes, and early introduction to trade and cultivation. Well-developed succulent leaf mesophyll tissue, an adaptive feature that likely contributed to the ecological success of the genus Aloe, is the main predictor for medicinal use among Aloe species, whereas evolutionary loss of succulence tends to be associated with losses of medicinal use. Phylogenetic analyses of plant use offer potential to understand patterns in the value of global plant diversity.

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The primary goal of volcanological studies is to reconstruct the eruptive history of active volcanoes, by correlating and dating volcanic deposits, in order to depict a future scenario and determine the volcanic hazard of an area. However, alternative methods are necessary where the lack of outcrops, the deposit variability and discontinuity make the correlation difficult, and suitable materials for an accurate dating lack. In this thesis, paleomagnetism (a branch of Geophysics studying the remanent magnetization preserved in rocks) is used as a correlating and dating tool. The correlation is based on the assumption that coeval rocks record similar paleomagnetic directions; the dating relies upon the comparison between paleomagnetic directions recorded by rocks with the expected values from references Paleo-Secular Variation curves (PSV, the variation of the geomagnetic field along time). I first used paleomagnetism to refine the knowledge of the pre – 50 ka geologic history of the Pantelleria island (Strait of Sicily, Italy), by correlating five ignimbrites and two breccias deposits emplaced during that period. Since the use of the paleomagnetic dating is limited by the availability of PSV curves for the studied area, I firstly recovered both paleomagnetic directions and intensities (using a modified Thellier method) from radiocarbon dated lava flows in São Miguel (Azores Islands, Portugal), reconstructing the first PSV reference curve for the Atlantic Ocean for the last 3 ka. Afterwards, I applied paleomagnetism to unravel the chronology and characteristics of Holocene volcanic activity at Faial (Azores) where geochronological age constraints lack. I correlated scoria cones and lava flows yielded by the same eruption on the Capelo Peninsula and dated eruptive events (by comparing paleomagnetic directions with PSV from France and United Kingdom), finding that the volcanics exposed at the Capelo Peninsula are younger than previously believed, and entirely comprised in the last 4 ka.

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This overview examines available circum-Antarctic glacial history archives on land, related to developments after the Last Glacial Maximum (LGM). It considers the glacial-stratigraphic and morphologic records and also biostratigraphical information from moss banks, lake sediments and penguin rookeries, with some reference to relevant glacial marine records. It is concluded that Holocene environmental development in Antarctica differed from that in the Northern Hemisphere. The initial deglaciation of the shelf areas surrounding Antarctica took place before 10000 C-14 yrs before present(sp), and was controlled by rising global sea level. This was followed by the deglaciation of some presently ice-free inner shelf and land areas between 10000 and 8000 yr sp. Continued deglaciation occurred gradually between 8000 yr sp and 5000 yr sp. Mid-Holocene glacial readvances are recorded from various sites around Antarctica. There are strong indications of a circum-Antarctic climate warmer than today 4700-2000 yr sp. The best dated records from the Antarctic Peninsula and coastal Victoria Land suggest climatic optimums there from 4000-3000 yr sp and 3600-2600 yr sp, respectively. Thereafter Neoglacial readvances are recorded. Relatively limited glacial expansions in Antarctica during the past few hundred years correlate with the Little Ice Age in the Northern Hemisphere.

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Ships’ protests have been used for centuries as legal documents to record and detail damages and indemnify Captains from fault. We use them in this article, along with data extracted through forensic synoptic analysis (McNally, 1994, 2004) to identify a tropical or subtropical system in the North Atlantic Ocean in 1785. They are shown to be viable sources of meteorological information. By comparing a damaging storm in New England in 1996, which included an offshore tropical system, with one reconstructed in 1785, we demonstrate that the tropical system identified in a ship’s protest played a significant role in the 1785 storm. With both forensic reconstruction and anecdotal evidence, we are able to assess that these storms are remarkably identical. The recurrence rate calculated in previous studies of the 1996 storm is 400–500 years. We suggest that reconstruction of additional years in the 1700s would provide the basis for a reanalysis of recurrence rates, with implications for future insurance and reinsurance rates. The application of the methodology to this new data source can also be used for extension of the hurricane database in the North Atlantic basin, and elsewhere, much further back into history than is currently available.

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Permafrost-related processes drive regional landscape dynamics in the Arctic terrestrial system. A better understanding of past periods indicative of permafrost degradation and aggradation is important for predicting the future response of Arctic landscapes to climate change. Here, we used a multi-proxy approach to analyze a ~4 m long sediment core from a drained thermokarst lake basin on the northern Seward Peninsula in western Arctic Alaska (USA). Sedimentological, biogeochemistical, geochronological, micropaleontological (ostracoda, testate amoeba) and tephra analyses were used to determine the long-term environmental Early-Wisconsin to Holocene history preserved in our core for Central Beringia. Yedoma accumulation dominated throughout the Early to Late-Wisconsin but was interrupted by wetland formation from 44.5 to 41.5 ka BP. The latter was terminated by deposition of 1 m of volcanic tephra, most likely originating from the South Killeak Maar eruption at about 42 ka BP. Yedoma deposition continued until 22.5 ka BP and was followed by a depositional hiatus in the sediment core between 22.5 and 0.23 ka BP. We interpret this hiatus as due to intense thermokarst activity in the areas surrounding the site, which served as a sediment source during the Late-Wisconsin to Holocene climate transition. The lake forming the modern basin on the upland initiated around 0.23 ka BP, which drained catastrophically in spring 2005. The present study emphasizes that Arctic lake systems and periglacial landscapes are highly dynamic and permafrost formation as well as degradation in Central Beringia was controlled by regional to global climate patterns and as well as by local disturbances.

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Depositional environments, stratigraphic relations, and 35 new AMS 14C dates at Cape Shpindler, Yugorski Peninsula, help constrain the late Pleistocene glacial and environmental history of the southern Kara Sea region. Fifteen- to fifty-meter-high coastal exposures reveal a complex package of shallow marine, fluvial, glacial, and postglacial deposits, and are documented here in a 19-km-long cross-section and eight vertical sections. The shallow marine (Unit A), estuarine or prodeltaic (Unit B), and fluvio-deltaic (Unit C) deposits contain an interglacial molluscan fauna, yield radiocarbon dates greater than 40 ka, and may correspond with a regional sea-level highstand during the Eemian. These units are overlain by a diamicton (Unit D), and are pervasively deformed by folds and low- to high-angle faults into a stacked glaciotectonic accretionary complex. The diamicton (Unit D) is a subglacial till, and associated massive ground ice with deformed debris bands (Unit E) appears to be relict glacier ice. Glaciotectonic structures document both southward- and northward-directed glacier movement. Above the till and associated glaciotectonic horizons lies 0- to 11-m-thick postglacial deposits of peatland, eolian, fluvial, and primarily lacustrine origin (Unit F). The postglacial deposits yield radiocarbon ages of 12.8 to 0.8 ka. Thus, at least one regional glaciation is prominently represented in the stratigraphy, and occurred probably after the Eemian but before 12.8 ka. We infer that the bulk of the glacial record corresponds with southward advance by an early Weichselian Kara Sea Ice Sheet, in agreement with other recently documented, regional records from Yamal Peninsula and the Pechora Basin. The timing and source of northward-directed glacier ice are less well constrained. Across the broad expanse of the Eurasian Arctic, Quaternary stratigraphy is still sparsely documented. The new data from Cape Shpindler fill a spatial gap in paleoenvironmental research.

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New pollen and radiocarbon data from the Bykovsky Peninsula document the Late Pleistocene and Holocene environmental history of the Laptev Sea coast. More than 60 AMS-14C and conventional 14C dates indicate that the deposits accumulated during the last 60,000 radiocarbon yr BP. High concentration of green alga colonies (Pediustrum and Botryococcus) in the investigated sediment show that sedimentation was mostly in shallow water environments. Scarce grass and sedge communities dominated the vegetation 53-60 kyr BP. Climate was cold and dry. Open Poaceae and Cypcraccae associations with Asteraceae, Ranunculaceae, and Cichoriaceac, dominated in the area about 48-42.5 kyr BP. Steppic communities with Artemisia and shrubby tundra communities with Salix and Betula sect. Nanae were also present. Climate was dry, but relatively warm. Vegetation cover became denser about 42.5-33.5 kyr BP, reflecting more favorable climate conditions. Scarce Poaceae communities with some Caryophyllaceae, Asteraceae, Cichoriaceae, and Selaginella rupestris covered the Bykovsky Peninsula area during the Sartan (Late Weichselian) stage about 26-16 kyr BP. Disturbed, uncovered soils were very common in the area. Climate was extremely cold and dry. Poaceae and Cyperaceae associations with Caryophyllaceae, Asteraceae, Cichoriaceae dominated the vegetation in the late Sartan, ca 16-12.2 kyr BP. Climate was significantly warmer than in the early Sartan time. The lee Complex sedimentation was interrupted about 12 kyr BP; most likely it was connected with the beginning of the Allerod warnring. Shrubby (Betula sect. Nanae, Alnusfnuicosa, Salix, Ericales) tundra was widely distributed on the Bykovsky Peninsula during the early-middle Holacene. Climate was most favorable between 8200 and 4500 yr BP. Vegetation became similar to modern after 4500 yr BP, suggesting a deterioration of climate.

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During Ocean Drilling Program Leg 178 we cored nine sites on the continental rise (Sites 1095, 1096, and 1101), continental shelf (Sites 1097, 1100, 1102, and 1103), and in an inner shelf basin, Palmer Deep (Sites 1098 and 1099), along the Pacific margin of the Antarctic Peninsula. Fossil diatoms are a key group that provides age constraint for these shelf site sediments to allow reconstruction of Antarctic Peninsula glacial history. This paper provides the systematic paleontology of diatoms applied in biostratigraphic and paleoceanographic studies and includes a total of 33 plates. Taxonomic confusion in previous reports, including biostratigraphically useful species such as Thalassiosira inura and Thalassiosira complicata, is discussed. These systematics and taxonomic discussions help to provide a reference for Neogene diatoms in the Southern Ocean.

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In wide areas of Northern Siberia, glaciers have been absent since the Late Pleistocene. Therefore, ground ice and especially ice wedges are used as archives for paleoclimatic studies. In the present study, carried out on the Bykovsky Peninsula, eastern Lena Delta, we were able to distinguish ice wedges of different genetic units by means of oxygen and hydrogen isotopes. The results obtained by this study on the Ice Complex, a peculiar periglacial phenomenon, allowed the reconstruction of the climate history with a subdivision of a period of very cold winters (60-55 ka), followed by a long stable period of cold winter temperatures (50-24 ka), Between 20 ka and I I ka, climate warming is indicated in stable isotope compositions, most probably after the Late Glacial Maximum. At that time, a change of the marine source of the precipitation from a more humid source to the present North Atlantic source region was assumed. For the Ice Complex, a continuous age-height relationship was established, indicating syngenetic vertical ice wedge growth and sediment accumulation rates of 0.7 m/ky. During the Holocene optimum, ice wedge growth was probably limited due to the extensive formation of lacustrine environments. Holocene ice wedges in thermokarst depressions (alases) and thermoerosional valleys (logs) were formed after climate deterioration from about 4.5 ka until the present. Winter temperatures were warmer at this time as compared to the cooler Pleistocene. Migration of bound water between ice wedges and segregated ice may have altered the isotopic composition of old ice wedges. The presence of ice wedges as diagnostic features for permafrost conditions since 60 ka, implies that a large glacier extending over the Laptev Sea shelf did not exist. For the remote non-glaciated areas of Northern Siberia, ice wedges were established as a powerful climate archive.