390 research outputs found

    Signatures of tetraether lipids reveal anthropogenic overprinting of natural organic matter in sediments of the Thames Estuary, UK

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    Intertidal foreshore sediments from a 110 km stretch of the Thames Estuary were analysed for glycerol dialkyl glycerol tetraethers (GDGTs) to track soil organic matter (OM) input and evaluate the impact of coastal urbanisation on their distribution. Concentration of branched (br)GDGTs ranged from < 1 to 15 μg/g organic carbon (OC) and crenarchaeol ranged from 0.6 to 19 μg/g OC. An overall decrease in brGDGTs was observed from the inner Thames (Brentford) to the outer Thames (Isle of Grain), suggesting a drop in soil OM input towards the sea. In contrast, crenarchaeol concentration was highest around east London rather than towards the open sea. Such elevated crenarchaeol concentration occurred in the section of the river most influenced by anthropogenic pollution, such as discharge points for London’s major sewage treatment plants, docks and power plants. The non-systematic spatial distribution of crenarchaeol was also reflected in the branched isoprenoid tetraether (BIT) index. The highest BIT values occurred upstream and in close proximity to salt marshes (0.8–1), whereas the lowest values (0.3–0.5) were towards the sea. However, unusually low values (0.4) were observed in the river section that had high crenarchaeol concentration. In contrast, bulk δ13C values were insensitive to London’s anthropogenic influence. This suggests that the natural systematic decrease in BIT index in the estuary is overprinted by London’s anthropogenic activity between Deptford Creek and Tilbury. We therefore advise caution when interpreting the BIT index for sediments in close proximity to megacities discharging industrial and municipal waste that can become incorporated into the near surface sedimentary record

    Molecular and bulk geochemical proxies in sediments from the Conwy Estuary, UK

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    Owing to their restricted riverine flow and greater numbers, small estuaries (annual discharge < 2000 m3 s–1) are important sites of organic carbon (OC) storage in sediments. The Conwy Estuary is an exemplar small rural-agricultural catchment which delivers a diverse pool of terrestrial OC to the Irish Sea. Thirty-nine surface sediments, covering a distance of 10.5 km, were taken transversal as well as longitudinal to the estuary to examine local and distant catchment inputs. Biomarkers (branched Glycerol Dialkyl Glycerol Tetraethers - brGDGTs, n-alkanes) and molecular and bulk proxies (BIT, Paq, TAR, δ13C, C/N), showed sediments were dominated by terrestrial inputs, with only sediments of the three most seaward sites showing stronger physical and geochemical characteristics of a marine influence (e.g., sandier sediments and lower BIT). Biomarker concentrations in the Conwy were comparable to the more urbanised Thames and the Clyde estuaries. The three estuaries showed similar fractional abundance of the brGDGTs, recording an inverse trend between the hexamethylated and the tetramethylated brGDGTs, and showing the pentamethylated brGDGTs as the dominant group. A systematic decrease in terrestrial biomarkers from bank to the main channel confirmed either a strong localised erosion/runoff process or a decrease in water velocity leading to a higher deposition

    Non-invasive methods for diagnosis of non-alcoholic fatty liver disease in children and adolescents: literature review / Métodos não invasivos para diagnóstico da doença hepática gordurosa não alcoólica em crianças e adolescentes: revisão da literatura

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    With the significant increase in the prevalence of nonalcoholic fatty liver disease (NAFLD) in children and adolescents and knowing its association with other clinical conditions and its implications in adult life, noninvasive diagnostic methods may represent new paths for prevention, early diagnosis and follow-up of the evolution of the disease. Objective: To describe noninvasive methods for diagnosing NAFLD in children and adolescents. Methods: integrative review. The articles were searched in the PubMed, Lilacs, Medline, Embase and Google Scholar databases, from August to December 2021. The descriptors "non-alcoholic fatty liver disease", "non-invasive methods", "biomarkers", "child" and "adolescent" were used. Results: Several biomarkers have been associated with the diagnosis of NAFLD, and among the most recognized are the lipid and glucose profile, liver enzymes, anti-inflammatory profile and assessment of body fat reserves. Antioxidant profile, uric acid, genome, lipidomics and proteomics evaluations are also predictors of steatosis; however, it remains to be determined whether these markers should be used together or in isolation for better results. Conclusions: Noninvasive markers for the diagnosis of NAFLD in children and adolescents are promising and, when used in association with clinical data, can be useful in guiding and managing this population for the prevention and control of NAFLD. 

    Shortened first-line TB treatment in Brazil: potential cost savings for patients and health services.

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    BACKGROUND: Shortened treatment regimens for tuberculosis are under development to improve treatment outcomes and reduce costs. We estimated potential savings from a societal perspective in Brazil following the introduction of a hypothetical four-month regimen for tuberculosis treatment. METHODS: Data were gathered in ten randomly selected health facilities in Rio de Janeiro. Health service costs were estimated using an ingredient approach. Patient costs were estimated from a questionnaire administered to 126 patients. Costs per visits and per case treated were analysed according to the type of therapy: self-administered treatment (SAT), community- and facility-directly observed treatment (community-DOT, facility-DOT). RESULTS: During the last 2 months of treatment, the largest savings could be expected for community-DOT; on average USD 17,351-18,203 and USD 43,660-45,856 (bottom-up and top-down estimates) per clinic. Savings to patients could also be expected as the median (interquartile range) patient-related costs during the two last months were USD 108 (13-291), USD 93 (36-239) and USD 11 (7-126), respectively for SAT, facility-DOT and community-DOT. CONCLUSION: Introducing a four-month regimen may result in significant cost savings for both the health service and patients, especially the poorest. In particular, a community-DOT strategy, including treatment at home, could maximise health services savings while limiting patient costs. Our cost estimates are likely to be conservative because a 4-month regimen could hypothetically increase the proportion of patients cured by reducing the number of patients defaulting and we did not include the possible cost benefits from the subsequent prevention of costs due to downstream transmission averted and rapid clinical improvement with less side effects in the last two months

    Extraction of rice bran oil using supercritical CO2 combined with ultrasound

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    CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORRice bran oil (RBO) contains oryzanol and tocopherols. Its recovery was performed using conventional techniques with toxic solvents that leave residues in the final product. Supercritical fluid extraction (SFE) has been used, obtaining high global yields352785794CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIOR552229/2011-32013/02203-6sem informaçã

    A DYNAMOMETRIC SYSTEM FOR STUDIES OF BALANCE WHILE QUIET STANDING (PROTOTYPE)

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    Studies on balance while quiet standing are frequently conducted through the measurement of the Center of Pressure (COP). Usually, a triaxial force platform is used in such studies, where the horizontal forces can be considered negligible. However, the cost of such instrument is a high limitation for research in this field. Considering that vertical reactions are significant they can be used to measure COP oscillations. This work describes the development of an inexpensive uniaxial dynamometric system to be used in balance studies

    ATENDIMENTO EDUCACIONAL ESPECIALIZADO DE ALUNOS COM DEFICIÊNCIA VISUAL: ESTUDO DE CASO EM UMA ESCOLA ESTADUAL

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    Este artigo busca abordar de maneira reflexiva como está sendo desenvolvida a&nbsp;assistência ao aluno com deficiência visual no Atendimento Educacional EspecializadoAEE de uma escola pública estadual de ensino do município de Humaitá- AM. Como&nbsp;também&nbsp;refletir como realmente acontece a inclusão dos alunos deficientes visuais na rede&nbsp;estadual, constatando adaptações curriculares, recursos didáticos e pedagógicos utilizados para&nbsp;estes alunos.&nbsp;Este estudo parte de uma abordagem qualitativa, na perspectiva descritiva.&nbsp;A construção dos dados foi realizada por meio da aplicação de entrevista&nbsp;semiestruturada, direcionada a 1 (um) professor atuante na sala de recurso da rede&nbsp;estadual. O estudo teve como base leituras e estudos de leis, decretos e autores que&nbsp;influenciam na educação do deficiente visual. Os resultados evidenciam que se necessita&nbsp;não apenas de salas de recursos para todas as escolas estaduais que recebem matrículas&nbsp;de alunos deficientes tipo 2, mais professores flexíveis que de certa forma colaborem&nbsp;com o trabalho do professor do AEE, disponibilizando parceria com o seu trabalho.&nbsp;&nbsp

    Contrasting sewage, emerging and persistent organic pollutants in sediment cores from the River Thames estuary, London, England, UK

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    Sedimentary organic pollution in the urban reaches of the Thames estuary is changing from fossil fuel hydrocarbons to emerging synthetic chemicals. De-industrialisation of London was assessed in three cores from Chiswick (Ait/Eyot) mud island using pharmaceuticals, faecal sterols, hydrocarbons (TPH, PAH), Black Carbon (BC) and organotins (TBT). These ranked in the order; BC 7590-30219 mg/kg, mean 16,000 mg/kg > TPH 770–4301, mean 1316 mg/kg > Σ16PAH 6.93–107.64, mean 36.46 mg/kg > coprostanol 0.0091–0.42 mg/kg, mean of 0.146 mg/kg > pharmaceuticals 2.4–84.8 μg/kg, mean 25 μg/kg. Hydrocarbons co-varied down-profile revealing rise (1940s), peak (1950s -1960s) and fall (1980s) and an overall 3 to 25-fold decrease. In contrast, antibiotics, anti-inflammatory (ibuprofen, paracetamol) and hormone (17β-estradiol) increased 3 to 50-fold toward surface paralleling increasing use (1970s-2018). The anti-epileptics, carbamazepine and epoxcarbamazepine showed appreciable down-core mobility. Faecal sterols confirmed non-systematic incorporation of treated sewage. Comparison to UK sediment quality guidelines indicate exceedance of AL2 for PAH whereas TBT was below AL1

    Linking land and lake: Using novel geochemical techniques to understand biological response to environmental change

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    The exploitation of lakes has led to large-scale contemporary impacts on freshwater systems, largely in response to catchment clearance. Such clearance is causing changes to carbon dynamics in tropical lakes which may have significance for wider carbon budgets, depending on the changes in carbon sequestration and mineralisation driven by changing roles of terrestrial and aquatic carbon in lakes over time. Despite increasing awareness of the pivotal role of carbon source in carbon dynamics, discriminating the source of carbon from a palaeolimnological record is rarely undertaken. Here we use novel geochemical techniques (brGDGTs, n-alkanes, Rock-Eval pyrolysis), paired with traditional analyses (diatoms, pollen), to elucidate changing sources of carbon through time and ecosystem response. Environmental changes at Lake Nyamogusingiri can be divided into three phases: Phase I (CE 1150-1275), a shallow and productive lake, where a diverse terrestrial environment is, initially, the main carbon source, before switching to an aquatic source; Phase II (CE 1275-1900), variable lake levels (generally in decline) with increasing productivity, and carbon is autochthonous in source; Phase III (CE 1900-2007), lake level declines, and the carbon is of a mixed source, though the terrestrially derived carbon is from a less diverse source. The organic geochemical analyses provide a wealth of data regarding the complexity of aquatic response to catchment and with-in lake changes. These data demonstrate show that small, tropical lake systems have the potential to bury high quantities of carbon, which has implications for the disruption of local biogeochemical cycles (C, P, N, and Si) both in the past, and the future as human and climate pressures increase
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