946 resultados para Scientific papers
Resumo:
Beachfront jurisdictional lines were established by the South Carolina Beachfront Management Act (SC Code §48- 39-250 et seq.) in 1988 to regulate the new construction, repair, or reconstruction of buildings and erosion control structures along the state’s ocean shorelines. Building within the state’s beachfront “setback area” is allowed, but is subject to special regulations. For “standard beaches” (those not influenced by tidal inlets or associated shoals), a baseline is established at the crest of the primary oceanfront sand dune; for “unstabilized inlet zones,” the baseline is drawn at the most landward point of erosion during the past forty years. The parallel setback line is then established landward of the baseline a distance of forty times the long-term average annual erosion rate (not less than twenty feet from the baseline in stable or accreting areas). The positions of the baseline and setback line are updated every 8-10 years using the best available scientific and historical data, including aerial imagery, LiDAR, historical shorelines, beach profiles, and long-term erosion rates. One advantage of science-based setbacks is that, by using actual historical and current shoreline positions and beach profile data, they reflect the general erosion threat to beachfront structures. However, recent experiences with revising the baseline and setback line indicate that significant challenges and management implications also exist. (PDF contains 3 pages)
Resumo:
Coastal managers need accessible, trusted, tailored resources to help them interpret climate information, identify vulnerabilities, and apply climate information to decisions about adaptation on regional and local levels. For decades, climate scientists have studied the impacts that short term natural climate variability and long term climate change will have on coastal systems. For example, recent estimates based on Intergovernmental Panel on Climate Change (IPCC) warming scenarios suggest that global sea levels may rise 0.5 to 1.4 meters above 1990 levels by 2100 (Rahmstorf 2007; Grinsted, Moore, and Jevrejeva 2009). Many low-lying coastal ecosystems and communities will experience more frequent salt water intrusion events, more frequent coastal flooding, and accelerated erosion rates before they experience significant inundation. These changes will affect the ways coastal managers make decisions, such as timing surface and groundwater withdrawals, replacing infrastructure, and planning for changing land use on local and regional levels. Despite the advantages, managers’ use of scientific information about climate variability and change remains limited in environmental decision-making (Dow and Carbone 2007). Traditional methods scientists use to disseminate climate information, like peer-reviewed journal articles and presentations at conferences, are inappropriate to fill decision-makers’ needs for applying accessible, relevant climate information to decision-making. General guides that help managers scope out vulnerabilities and risks are becoming more common; for example, Snover et al. (2007) outlines a basic process for local and state governments to assess climate change vulnerability and preparedness. However, there are few tools available to support more specific decision-making needs. A recent survey of coastal managers in California suggests that boundary institutions can help to fill the gaps between climate science and coastal decision-making community (Tribbia and Moser 2008). The National Sea Grant College Program, the National Oceanic and Atmospheric Administration's (NOAA) university-based program for supporting research and outreach on coastal resource use and conservation, is one such institution working to bridge these gaps through outreach. Over 80% of Sea Grant’s 32 programs are addressing climate issues, and over 60% of programs increased their climate outreach programming between 2006 and 2008 (National Sea Grant Office 2008). One way that Sea Grant is working to assist coastal decision-makers with using climate information is by developing effective methods for coastal climate extension. The purpose of this paper is to discuss climate extension methodologies on regional scales, using the Carolinas Coastal Climate Outreach Initiative (CCCOI) as an example of Sea Grant’s growing capacities for climate outreach and extension. (PDF contains 3 pages)
Resumo:
This paper discusses the particular contribution of the SSSI (Sites of Special Scientific Interest) as a way of nature conservation for rivers. In 1989, the Nature Conservancy Council proposed a dual selection system for selection of rivers; either (1) "Whole river" SSSIs representing the main types of river, or rivers which show classic and representative transitions down their lengths, or (2) "Sectional" SSSIs which are shorter stretches of river with high nature conservation interest. The NCC has recently classified all SSSIs with a river interest into 4 categories: - river SSSIs, river valley SSSIs, river adds interest - where the river clearly adds biological interest to the site, and rivers of incidental interest. The overall length of river SSSIs amounts to almost 1000 km.
Resumo:
An account is given of a study of African tropical waters, drawing on the personal experiences of the author. Reviewing developments since 1900, the author examines the way in which research has developed and the influence the changes in the policitcal map of Africa, in particular the change from colonial rule, has had on research.
Resumo:
The method of E.V. Borutski was used for determining the production of chironomids, that is, the dynamics of the number and biomass of the larvae were analysed, their death, a calculation of emergence and the number of deposited egg layings was carried out. In addition to the method of Borutski, the authors also calculated the seasonal dynamics of the number of larvae of the younger age stages in the microbenthos.
Resumo:
This study was conducted to look into the relationship between mouth size and the total length of larval fish, and the growth in total length of larval fish in one or within a one-year period. Study material was gathered in the South China Sea, the Bay of Bangkok and the Vietnamese coast. This translation focuses on methods and conclusions of the original (longer) paper.
Resumo:
The word ”Broads” is used to describe a series of relatively shallow lakes resulting from the flooding of medieval peat diggings. Broadland is essentially freshwater, but because the rivers have such low gradients the lower reaches are brackish. The influence of tide is particularly apparent on the River Yare; in Norwich 40 km from the sea there is a vertical movement of half a metre at spring tide. This study examines the problems that the broadlands are facing. The problems are basically the progressive loss of aquatic plants, in particular the macro- phytes, animal life, outbreaks of avian botulism, occasional fish kills due to a toxin produced by the blue-green alga Prymesium parvum and the emergence of very heavy algal blooms. The main factor for the deteriation of the Broaslands is the eutrophication resulting from enhanced nutrient inputs, in particular of nitrates and phosphates, from a variety of sources. The most important of these are sewage effluents, agricultural drainage, which includes fertilisers and nutrient rich effluents from piggeries and dairy un
Resumo:
Two working parties, the Working Party on Tuna Tagging in the Pacific and Indian Oceans and the Working Party on Tuna Tagging in the Atlantic and Adjacent Seas, were formed by the Food and Agriculture Organization (FAD) of the United Nations in 1966 (Anonymous, 1966c). The conveners of these working parties were Dr. James Joseph of the Inter-American Tropical Tuna Commission (IATTC) and Mr. FrankJ. Mather, III, of the Woods Hole Oceanographic Institution (WHOI). In 1969 it was recommended that the working parties direct their attention toward billfishes, as well as tunas (Anonymous, 1969h: 5). One report (Joseph and working party, 1969) was published by the Pacific and Indian Oceans group and two (Mather and working party, 1969 and 1972) were published by the Atlantic Ocean and adjacent seas group. Each of the three working party reports included a bibliography of tuna and billfish tagging. The compiler of this bibliography, beginning in 1970, prepared numerous memoranda to the members of the working party, most of which included lists of papers on tuna and billfish tagging which had come to his attention, either directly or through members of the working party. The bibliographies in the three working party reports and the lists of references in the memoranda form the basis for the present bibliography.
Resumo:
From a special issue: A Brief History of the Charles Darwin Foundation for the Galapagos Islands 1959-1988
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O câncer do colo do útero é responsável por 7% do total dos óbitos por câncer entre a população feminina brasileira e tem uma incidência estimada de 20/100 mil para todo o país. Evidências científicas comprovam que o papilomavírus humano (HPV) é causa necessária para a ocorrência deste tipo de câncer. Ações de prevenção e controle recomendadas têm se baseado no conhecimento sobre a epidemiologia da doença. Os estudos realizados no Brasil sobre a prevalência da infecção por HPV disponíveis na literatura têm características variadas que ainda não foram analisadas em conjunto e de modo sistematizado. O objetivo deste estudo foi realizar uma revisão sistemática dos artigos sobre prevalência do HPV em mulheres brasileiras considerando as prevalências globais e entre aquelas com exame citológico cervical normal. Foram selecionados todos os artigos após busca nas bases de dados Medline e BVS, tomando-se como termos human papillomavirus, HPV, prevalence Brazil. Entre 1989 e 2008, foram selecionados 155 artigos, sendo 133 nas bases de dados e 22 referências secundárias. Após leitura de título e resumo, 82 artigos foram incluídos, e a seguir submetidos à leitura integral dos textos, sendo enfim selecionados 14 artigos, os quais representaram estudos de quatro grandes regiões brasileiras (Sudeste 43,0%, Sul 21,4%, Nordeste 21,4% e Norte 7,1%). Em sua maioria (64,5%), trata-se de artigos que relatam desenho transversal. Com referência ao método de identificação do HPV nas mulheres, em oito (57,1%) artigos, há relato do emprego de PCR para tipagem do HPV e, em sete (50,0%) artigos, houve emprego de HC para detecção do HPV. As amostras variaram de 49 a 2329 mulheres. A prevalência global de infecção do colo do útero pelo HPV variou entre 13,7 e 54,3%, e para as mulheres com citologia normal, a prevalência de infecção pelo HPV no colo do útero varia entre 10 e 24,5%. Os resultados obtidos permitiram criar um panorama das prevalências e da distribuição da infecção pelo HPV e principais tipos em mulheres com citologia cervical normal e assim contribuir para a compreensão da distribuição da infecção pelo HPV no país, auxiliando na orientação de outros estudos bem como de políticas voltadas para a saúde da mulher e prevenção do câncer do colo do útero.
Resumo:
Recent experimental work in the field of synthetic protocell biology has shown that prebiotic vesicles are able to 'steal' lipids from each other. This phenomenon is driven purely by asymmetries in the physical state or composition of the vesicle membranes, and, when lipid resource is limited, translates directly into competition amongst the vesicles. Such a scenario is interesting from an origins of life perspective because a rudimentary form of cell-level selection emerges. To sharpen intuition about possible mechanisms underlying this behaviour, experimental work must be complemented with theoretical modelling. The aim of this paper is to provide a coarse-grain mathematical model of protocell lipid competition. Our model is capable of reproducing, often quantitatively, results from core experimental papers that reported distinct types vesicle competition. Additionally, we make some predictions untested in the lab, and develop a general numerical method for quickly solving the equilibrium point of a model vesicle population.
Resumo:
Este trabalho pretende realizar uma história cultural ou "arqueologia" dos abrigos espíritas para a infância no Brasil, construídos como verdadeiros"monumentos" da fé espírita, cuja materialização começa a ocorrer na segunda década do século XX, a partir de algumas iniciativas ou instituições que se tornaram pioneiras, tais como o Abrigo Thereza de Jesus, fundado em 1919 na cidade do Rio de Janeiro. Inspirados no lema "Fora da caridade não há salvação", um dos pilares do aspecto religioso do Espiritismo, os espíritas entram na milenar história das práticas de proteção à infância apenas na Idade Moderna. A doutrina espírita,procurando estabelecer, desde o seu "nascimento", a aliança entre Ciência e Religião, acaba adquirindo a feição de uma "religião moderna", reinvenção da tradição cristã em tempos de racionalismo e cientificismo. Entretanto, apesar da ênfase doutrinária no exercício da caridade individual e silenciosa como fundamento para a evolução espiritual, o movimento espírita acaba ampliando este sentido inicial presente nas obras de Allan Kardec, publicadas em Paris entre 1857 e 1869, tendo incorporado ou se apropriado de representações e práticas de caridade que foram desenvolvidas histórica e culturalmente dentro da tradição cristã mais antiga.