Bed shear stress measurements in dam break and swash flows

A novel shear plate was used to make direct bed shear stress measurements in laboratory dam break and swash flows on smooth, fixed, impermeable beds. The pressure gradient due to the slope of the fluid free-surface across the plate was measured using pressure transducers. Surface elevation was measured at five locations using acoustic displacement sensors. Flow velocity was measured using an Acoustic-Doppler Velocimeter and calculated using the ANUGA inundation model. The measured bed shear stress at the dam break fluid tip for an initially dry, horizontal bed was close to twice that estimated using steady flow theory. The temporal variation of swash bed shear stress showed a large peak in landward directed stress at the uprush tip, followed by a rapid decay throughout the uprush flow interior. The peak seaward directed stress during the backwash phase was less than half that measured in the uprush. Close to the still water line, in the region of bore collapse and at the time of initial uprush, favourable pressure gradients were measured. In the lower swash region predominately weak adverse pressure gradients were measured.

The functional outcome of children after a burn injury: A pilot study

Assessment of functional outcome can be used as a measure of the effectiveness of intervention during recovery from a burn injury. This pilot study identifies the factors that are likely to be most important for determining standardized functional outcome measures for children after a burn injury; it highlights the contribution of these factors to variations in children's postburn outcomes. A focus group of 8 parents and a self-report questionnaire administered to 12 children and 13 parents were the means of obtaining information for this exploratory study. Itching was found to be one of the primary impairments that contributed to reduced functional outcome during skin healing after a burn injury. The activities of children who had been burned that were most frequently affected by the injury (as reported by parents) were schoolwork and sports; these were closely followed by sleeping, playing with other children, and unliked activities. Least affected activities were enjoying the family, eating, seeing friends, watching television, and bathing or showering. Eighty-five percent of parents reported at least some level of interference with the listed daily activities. Burn injuries are likely to cause interference with several aspects of a patient's daily life. As a result, families require ongoing support and monitoring. Further research should longitudinally compare the performance of children who have been burned with other children and adolescents.

A two-dimensional analytical solution of groundwater responses to tidal loading in an estuary and ocean

Previous studies on tidal dynamics of coastal aquifers have focussed on the inland propagation of oceanic tides in the cross-shore direction, a configuration that is essentially one-dimensional. Aquifers at natural coasts can also be influenced by tidal waves in nearby estuaries, resulting in a more complex behaviour of head fluctuations in the aquifers. We present an analytical solution to the two-dimensional depth-averaged groundwater flow equation for a semi-infinite aquifer subject to oscillating head conditions at the boundaries. The solution describes the tidal dynamics of a coastal aquifer that is adjacent to a cross-shore estuary. Both the effects of oceanic and estuarine tides on the aquifer are included in the solution. The analytical prediction of the head fluctuations is verified by comparison with numerical solutions computed using a standard finite-difference method. An essential feature of the present analytical solution is the interaction between the cross- and along-shore tidal waves in the aquifer area near the estuary's entry. As the distance from the estuary or coastline increases, the wave interaction is weakened and the aquifer response is reduced, respectively, to the one-dimensional solution for oceanic tides or the solution of Sun (Sun H. A two-dimensional analytical solution of groundwater response to tidal loading in an estuary, Water Resour Res 1997;33:1429-35) for two-dimensional non-interacting tidal waves. (C) 2000 Elsevier Science Ltd. All rights reserved.

A randomised controlled trial evaluating the effect of immersion bath on labour pain

Objective: to evaluate the effect of an immersion bath on pain magnitude during the first stage of tabour. Design: a randomised controlled trial comparing the pain scores of bathing and non-bathing nulliparous women during birth was employed. Setting: the study was conducted at the Normal Birth Center of Amparo Maternal, Sao Paulo, Brazil. Participants: 108 birthing women, with 54 women randomly assigned to each group. Interventions: when the birthing women presented at 6-7cm of cervical dilation, they were placed in an immersion bath for 60 mins. Outcome measures: pain scores, using a behavioural pain scale and a numeric scale, were recorded at two evaluation time points: at 6-7cm of cervical dilation and 1 h after the first pain score evaluation. Findings: at the first evaluation, on the behavioural scale, the means were 2.1 for both groups (p = 0.914; 95% confidence intervals (CI) 1.9-2.3 for the control group and 2.0-2.2 for the experimental group). On the numeric scale, the means were 8.7 and 8.5 for the control and experimental groups, respectively (p = 0.235; 95% Cl 8.2-9.2 for the control group and 8.1-8.9 for the experimental group). At the second evaluation, the pain score means for both scales were statistically higher in the control group than in the experimental group. On the behavioural scale, the scores were 2.4 vs. 1.9, respectively, for the control and experimental groups (p<0.001; 95% Cl 2.2-2.6 for the control group and 1.7-2.1 for the experimental group). On the numeric scale, the scores were 9.3 vs. 8.5, respectively, for the control and experimental groups (p<0.05; 95% Cl 8.9-9.7 for the control group and 8.1-8.9 for the experimental group). Conclusions: mean tabour pain scores in the control group were significantly higher than those in the experimental group. The present findings suggest that use of an immersion bath is a suitable alternative form of pain relief for women during tabour. (C) 2007 Elsevier Ltd. All rights reserved.

Turbulent blood flow plays an essential localizing role in the development of atherosclerotic lesions in experimentally induced hypercholesterolaemia in rats

Taking into account that atherosclerosis is a focal disease and high levels of plasma cholesterol are closely correlated with its pathogenesis, it is a challenge to explain how equal concentrations of cholesterol bathing the endothelium can produce local, rather than global, effects on arteries. The focal distribution of atherosclerotic lesions has been considered to be dependent, at least in part, on hydrodynamic factors. The present study was carried out to further test the hypothesis that these forces are an important localizing factor in rats feeding a hypercholesterolaemic diet and submitted to infra-diaphragmatic aortic constriction. These animals develop a normotensive prestenotic region with laminar blood flow that serves as control for a normotensive poststenotic region with turbulent blood flow. Our findings clearly demonstrated that the combination of turbulent blood flow and low wall shear stress (WSS) in the presence of hypercholesterolaemia and oxidative stress creates conditions to the formation of focally distributed incipient atherosclerotic lesions observed in the poststenotic segment. In contrast, only diffuse fatty streaks could be observed in the normotensive prestenotic segment with laminar blood flow and normal WSS in the presence of hypercholesterolaemia and oxidative stress. Although haemodynamic forces are not by themselves responsible for the pathogenesis of atherosclerosis, they prime the local vascular wall in which the lesion develop. Further studies are required to establish how haemodynamic forces are detected and transduced into chemical signalling by the cells of the artery wall and then converted into pathophysiologically relevant phenotypic changes.

The toxins of Lyngbya majuscula and their human and ecological health effects

Lyngbya majuscula is a benthic filamentous marine cyanobacterium, which in recent years appears to have been increasing in frequency and size of blooms in Moreton Bay, Queensland. It has a worldwide distribution throughout the tropics and subtropics in water to 30m. It has been found to contain a variety of chemicals that exert a range of biological effects, including skin, eye and respiratory irritation. The toxins lyngbyatoxin A and debromoaplysiatoxin appear to give the most widely witnessed biological effects in relation to humans, and experiments involving these two toxins show the formation of acute dermal lesions. Studies into the epidemiology of the dermatitic, respiratory and eye effects of the toxins of this organism are reviewed and show that Lyngbya induced dermatitis has occurred in a number of locations. The effects of aerosolised Lyngbya in relation to health outcomes were also reported. Differential effects of bathing behaviour after Lyngbya exposure were examined in relation to the severity of health outcomes. The potential for Lyngbya to exhibit differential toxicologies due to the presence of varying proportions of a range of toxins is also examined. This paper reviews the present state of knowledge on the effects of Lyngbya majuscula on human health, ecosystems and human populations during a toxic cyanobacterial bloom. The potential exists for toxins from Lyngbya majuscula affecting ecological health and in particular marine reptiles. (C) 2001 Elsevier Science Ltd. All rights reserved.

Acute stress hyperglycemia in cats is associated with struggling and increased concentrations of lactate and norepinephrine

We characterized the changes in blood glucose concentrations in healthy cats exposed to a short stressor and determined the associations between glucose concentrations, behavioral indicators of stress, and blood variables implicated in stress hyperglycemia (plasma glucose, lactate, insulin, glucagon, cortisol, epinephrine, and norepinephrine concentrations). Twenty healthy adult cats with normal glucose tolerance had a 5-minute spray bath. Struggling and vocalization were the most frequent behavioral responses. There was a strong relationship between struggling and concentrations of glucose and lactate. Glucose and lactate concentrations increased rapidly and significantly in all cats in response to bathing, with peak concentrations occurring at the end of the bath (glucose baseline 83 mg/dL, mean peak 162 mg/dL; lactate baseline 6.3 mg/dL, mean peak 64.0 mg/dL). Glucose response resolved within 90 minutes in 12 of the 20 cats. Changes in mean glucose concentrations were strongly correlated with changes in mean lactate (r =.84; P

Caracterização morfodinâmica do litoral Norte Fluminense, RJ, Brasil

A morfologia das praias é reflexo da ação hidrodinfunica com o tipo de sedimento disponível. Esta interação se dá a partir da base de ação das ondas, tornando-se mais efetiva na zona de arrebentação onde a energia é dissipada, originando na zona de surfe que se estende em direção à linha de costa até Q limite do espraiamento na face de praia. O objetivo deste trabalho é apresentar as características morfodinâmicas do litoral NE do Estado do Rio de Janeiro, baseando-se na análise da variação espaço Hemporal de perfis de praia, na morfologia da plataforma continental e em fotos aéreas. Os perfis de praia foram levantados durante cinco anos pela PETROBRÁS S/A, em oito estações ao longo do litoral. O comportamento morfodinâmico distinto de setores do litoral estudado é função do padrão de ondas e direção da linha de costa, morfologia da plataforma interna controlando a extensão da zona de surfe e o número de zonas de arrebentação, características dos sedimentos e gradiente da face de praia. Foram reconhecidos quatro compartimentos morfodinâmicos distintos, com base na morfologia dos perfis praiais e plataforma interna, no índice de mobilidade da linha de praia, granulometria x gradiente da face de praia e o parâmetro Q. Os quatro compartimentos são: Atafona/Foz do Rio Paraíba do Sul - estágio morfodinâmico intermediário a dissipativo, com o maior índice de mobilidade e elevada taxa de erosão; Sul de Atafona-Cabo de São Tomé - estágio intermediário a refletivo com baixo índice de mobilidade da praia; Cabo de São Tomé - estágio refletivo a intermediário com alto índice de mobilidade da praia; Cabo de São Tomé-Cabiúnas - estágio refletivo com baixo índice de mobilidade.

A utilização das praias como espaços de esporte e lazer : tensões entre o público e o privado

O presente estudo se propõe a investigar a relação estabelecida entre o Poder Público e a iniciativa privada na utilização das praias do município de Vila Velha/ES como espaços de esporte e lazer, analisando se e como as políticas formuladas para utilização das praias podem incidir no acesso do cidadão ao esporte e ao lazer, no período de 2009-2012. Trata-se de uma pesquisa de abordagem qualitativa, que utiliza como planos de pesquisa os estudos descritivo e explicativo. A realização do estudo ocorreu em etapas, constando de levantamento bibliográfico, coleta de dados documentais, inserção em campo e por fim, análise dos dados coletados, utilizando como meio a técnica de análise de conteúdo (BARDIN, 2009). Os resultados da pesquisa apontam que a Secretaria de Esportes e Lazer de Vila Velha/ES, através das políticas implementadas, não buscou garantir o acesso do cidadão ao esporte e ao lazer, considerando que as políticas adotadas não contemplam a gestão dos espaços públicos e das práticas de esporte e lazer. Além disso, as parcerias estabelecidas com a iniciativa privada não são institucionalizadas e não preveem o acesso livre e gratuito ao cidadão, comprometendo o direito previsto constitucionalmente no acesso ao esporte e ao lazer.

Entre rios, praias e planetas : travessias do congo da Barra do Jucu

O Espírito Santo abriga grande diversidade de expressões populares tradicionais que se dividem em grupos, saberes e celebrações. Uma das práticas mais evidentes são as bandas de Congo que abrangem grande parte do Estado e ganham cada vez mais notoriedade. A Barra do Jucu é uma das comunidades mais antigas do Espírito Santo, uma vila de pescadores que séculos atrás compunha parte da grande fazenda Araçatiba fundada pelos Jesuítas e administrada no século XIX pelo coronel Sebastião Vieira Machado. A diversidade cultural dessa região habitada por africanos, indígenas e europeus, propiciou o surgimento de práticas populares como a Marujada, a Folia de Reis e as Bandas de Congo, que persistem até hoje nos municípios de Cariacica, Vila Velha, Guarapari e Viana, no passado, pertencentes à grande fazenda Araçatiba. A formação do Congo na Barra do Jucu é resultado de rodas informais realizadas por conguistas de comunidades ribeirinhas vizinhas, promovidas principalmente pelo senhor Ignácio Vieira Machado, descendente do coronel Sebastião e lideradas por Alcides Gomes da Silva, descendente de negros africanos e açorianos habitantes da fazenda Araçatiba. Durante muito tempo essa prática foi marginalizada, mas atualmente o Congo é considerado um ícone da cultura capixaba. Essa ressignificação está ligada a um processo de valorização e projeção midiática que se iniciou nos anos 1980 e se intensificou nas décadas seguintes. Boa parte dos movimentos e eventos que estimularam esse processo ocorreu na comunidade da Barra do Jucu. Por outro lado, políticos, empresários, indústria do entretenimento e outros setores sociais, aproveitam cada vez mais dessa ascensão do Congo utilizando os grupos tradicionais para fins lucrativos e promocionais. De prática marginal até se tornar ícone cultural, o Congo da Barra do Jucu passou por fazendas, rios, praias e planetas. E sobre essas travessias não só geográficas, mas sociais, culturais e políticas é que este trabalho pretende refletir, além das práticas tradicionais dos grupos e seus usos, buscando trazer à tona as relações entre conguistas, instituições públicas e privadas, mídia e público.

Geostatistical Mapping of Outfall Plume Dispersion Data gathered with an autonomous underwater vehicle

The main purpose of this study was to examine the applicability of geostatistical modeling to obtain valuable information for assessing the environmental impact of sewage outfall discharges. The data set used was obtained in a monitoring campaign to S. Jacinto outfall, located off the Portuguese west coast near Aveiro region, using an AUV. The Matheron’s classical estimator was used the compute the experimental semivariogram which was fitted to three theoretical models: spherical, exponential and gaussian. The cross-validation procedure suggested the best semivariogram model and ordinary kriging was used to obtain the predictions of salinity at unknown locations. The generated map shows clearly the plume dispersion in the studied area, indicating that the effluent does not reach the near by beaches. Our study suggests that an optimal design for the AUV sampling trajectory from a geostatistical prediction point of view, can help to compute more precise predictions and hence to quantify more accurately dilution. Moreover, since accurate measurements of plume’s dilution are rare, these studies might be very helpful in the future for validation of dispersion models.

Are known cyanotoxins involved in the toxicity of picoplanktonic and filamentous north atlantic marine cyanobacteria?

Eight marine cyanobacteria strains of the genera Cyanobium, Leptolyngbya, Oscillatoria, Phormidium, and Synechococcus were isolated from rocky beaches along the Atlantic Portuguese central coast and tested for ecotoxicity. Strains were identified by morphological characteristics and by the amplification and sequentiation of the 16S rDNA. Bioactivity of dichloromethane, methanol and aqueous extracts was assessed by the Artemia salina bioassay. Peptide toxin production was screened by matrix assisted laser desorption/ionization time of flight mass spectrometry. Molecular analysis of the genes involved in the production of known cyanotoxins such as microcystins, nodularins and cylindrospermopsin was also performed. Strains were toxic to the brine shrimp A. salina nauplii with aqueous extracts being more toxic than the organic ones. Although mass spectrometry analysis did not reveal the production of microcystins or other known toxic peptides, a positive result for the presence of mcyE gene was found in one Leptolyngbya strain and one Oscillatoria strain. The extensive brine shrimp mortality points to the involvement of other unknown toxins, and the presence of a fragment of genes involved in the cyanotoxin production highlight the potential risk of cyanobacteria occurrence on the Atlantic coast.

Efeitos da hidrodinâmica em comunidades biológicas de praias de calhau rolado em áreas marinhas protegidas

Jornadas "Ciência nos Açores – que futuro?", Ponta Delgada, 7-8 de Junho de 2013.

Routine screening of harmful microorganisms in beach sands: implications to public health

Beaches worldwide provide recreational opportunities to hundreds of millions of people and serve as important components of coastal economies. Beach water is often monitored for microbiological quality to detect the presence of indicators of human sewage contamination so as to prevent public health outbreaks associated with water contact. However, growing evidence suggests that beach sand can harbor microbes harmful to human health, often in concentrations greater than the beach water. Currently, there are no standards for monitoring, sampling, analyzing, or managing beach sand quality. In addition to indicator microbes, growing evidence has identified pathogenic bacteria, viruses, and fungi in a variety of beach sands worldwide. The public health threat associated with these populations through direct and indirect contact is unknown because so little research has been conducted relating to health outcomes associated with sand quality. In this manuscript, we present the consensus findings of a workshop of experts convened in Lisbon, Portugal to discuss the current state of knowledge on beach sand microbiological quality and to develop suggestions for standardizing the evaluation of sand at coastal beaches. The expert group at the "Microareias 2012" workshop recommends that 1) beach sand should be screened for a variety of pathogens harmful to human health, and sand monitoring should then be initiated alongside regular water monitoring; 2) sampling and analysis protocols should be standardized to allow proper comparisons among beach locations; and 3) further studies are needed to estimate human health risk with exposure to contaminated beach sand. Much of the manuscript is focused on research specific to Portugal, but similar results have been found elsewhere, and the findings have worldwide implications.

Comparison of Aspergillus species-complexes detected in different environmental settings

Purpose: Samples from different environmental sources were screened for the presence of Aspergillus, and the distribution of the different species-complexes was determined in order to understand differences among that distribution in the several environmental sources and which of these species complexes are present in specific environmental settings. Methods: Four distinct environments (beaches, poultries, swineries and hospital) were studied and analyzed for which Aspergillus complexes were present in each setting. After plate incubation and colony isolation, morphological identification was done using macro- and microscopic characteristics. The universal fungal primers ITS1 and ITS4 were used to amplify DNA from all Aspergillus isolates, which was sequenced for identification to species complex level. SPSS v15.0 for Windows was used to perform the statistical analysis. Results: Thirty-nine isolates of Aspergillus were recovered from both the sand beach and poultries, 31 isolates from swineries, and 80 isolates from hospital environments, for a total 189 isolates. Eleven species complexes were found total. Isolates belonging to the Aspergillus Versicolores species-complex were the most frequently found (23.8%), followed by Flavi (18.0%), Fumigati (15.3%) and Nigri (13.2%) complexes. A significant association was found between the different environmental sources and the distribution of the several species-complexes (p<0.001); the hospital environment had a greater variability of species-complexes than other environmental locations (10 in hospital environment, against nine in swine, eight in poultries and seven in sand beach). Isolates belonging to Nidulantes complex were detected only in the hospital environment, whereas the other complexes were identified in more than one setting. Conclusion: Because different Aspergillus complexes have different susceptibilities to antifungal drugs, and different abilities in producing mycotoxins, knowledge of the species-complex epidemiology for each setting may allow preventive or corrective measures to be taken toward decreasing professional workers or patient exposure to those agents.