47 resultados para Aerden, Dries
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Este trabalho teve como objetivo investigar o efeito do tamanho das ilhas de floresta, de suas distâncias para a floresta contínua (isolamento) e para as estradas adjacentes sobre a comunidade de Scarabaeidae coprófagos. Amostras foram coletadas em 24 ilhas de floresta semidecídua, entre 0,5 e 360 ha, em uma matriz de savana amazônica e em oito locais em mata contínua predominantemente secundária, semidecídua, na região de Alter do Chão, Santarém, Pará. Os Scarabaeidae foram coletados com armadilhas do tipo pitfall com isca (fezes humanas) em dois períodos sazonais (seca e chuva). Para cada ponto de coleta foram instaladas 10 armadilhas distribuídas em dois transectos de 250 m, distantes 100 m entre si. Em cada transecto foram colocadas 5 armadilhas distantes 50 m entre si. Para cada local de coleta, foi registrado o DAP de todos os caules com diâmetro igual ou superior a 5 cm, em quatro transectos de 250 x 2 m, sendo estes dados utilizados para derivar os índices da estrutura da vegetação (diâmetro médio e número de indivíduos). A área, perímetro e as distâncias das ilhas para a floresta contínua foram calculadas utilizando-se respectivamente as extensões “X-Tools” e “Nearest Features v3.6d” para ArcView, sobre o mapa da área digitalizado a partir de uma imagem de Landsat TM de 1996. Os exemplares coletados foram identificados com a ajuda de bibliografia especializada e de especialistas. Para a caracterização da fauna, as espécies encontradas foram comparadas com uma lista de espécies gerada a partir de publicações para o Cerrado, Amazônia e ecótonos de transição (floresta–cerrado) brasileiros. Para avaliar a robustez da amostragem, foram empregadas curvas de rarefação e obtidas estimativas de riqueza empregando-se diversos estimadores. Para a análise dos padrões das comunidades, foi utilizada uma análise HNMDS (Semi-strong Hibrid Multidimensional Scaling) utilizandose a distância de Bray-Curtis. Foram encontrados 18 gêneros e 36 espécies pertencentes aos biomas do Cerrado e da Amazônia, mas não foi possível ter uma noção completa da parcela de cada bioma representada neste ecótono de transição savana-floresta, uma vez que as amostras não foram suficientes para o levantamento exaustivo da riqueza de Scarabaeidae. A ordenação mostrou uma tendência de agrupamento das florestas contínuas e de separação destas das ilhas de floresta. Apesar de o levantamento ter registrado um maior número de espécies nas ilhas de floresta que nas áreas de floresta contínua, as comunidades apresentaram um forte padrão hierárquico [P (T< 14,87°)<0,001], indicando que nas ilhas estão persistindo apenas uma parcela do total de espécies da região. Não foi encontrada uma relação entre a composição de Scarabaeidae e o tamanho e a forma das ilhas de floresta. Mas foi encontrada uma relação significativa entre a composição (eixo 1) e o isolamento (F=5,363, P=0,031) e a composição (eixo 1) e o número de árvores (DAP > 5 cm) (F=6,103, P=0,012, corrigido por Bonferroni). O número de árvores de cada local de amostragem foi relacionado com a proximidade de estradas (0,658), o que reforça a idéia de que as estradas estão contribuindo para mudanças na estrutura da vegetação, que por sua vez tem um efeito sobre a fauna de Scarabaeidae.
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BACKGROUND AND OBJECTIVES: Gross motor (GM) deficits are often reported in children with prenatal alcohol exposure (PAE), but their prevalence and the domains affected are not clear. The objective of this review was to characterize GM impairment in children with a diagnosis of fetal alcohol spectrum disorder (FASD) or moderate to heavy maternal alcohol intake.METHODS: A systematic review with meta-analysis was conducted. Medline, Embase, Allied and Complementary Medicine Database, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, PEDro, and Google Scholar databases were searched. Published observational studies including children aged 0 to <= 18 years with (1) an FASD diagnosis or moderate to heavy PAE, or a mother with confirmed alcohol dependency or binge drinking during pregnancy, and (2) GM outcomes obtained by using a standardized assessment tool. Data were extracted regarding participants, exposure, diagnosis, and outcomes by using a standardized protocol. Methodological quality was evaluated by using Strengthening the Reporting of Observational Studies in Epidemiology guidelines.RESULTS: The search recovered 2881 articles of which 14 met the systematic review inclusion criteria. The subjects' mean age ranged from 3 days to 13 years. Study limitations included failure to report cutoffs for impairment, nonstandardized reporting of PAE, and small sample sizes. The meta-analysis pooled results (n = 10) revealed a significant association between a diagnosis of FASD or moderate to heavy PAE and GM impairment (odds ratio: 2.9; 95% confidence interval: 2.1-4.0). GM deficits were found in balance, coordination, and ball skills. There was insufficient data to determine prevalence.CONCLUSIONS: The significant results suggest evaluation of GM proficiency should be a standard component of multidisciplinary FASD diagnostic services.
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The hydroponic cultivation of vegetables has increased markedly in recent years, however, little is known about its chemical composition, which is of extreme importance in view of changing food habits of a considerable fraction of the population seeking food quality. For this reason, cultivation of watercress, chicory, rocket and lettuce American (Lucy Brown) and smooth (cv. Regina) were grown in hydroponics, NFT system, aiming to evaluate the yield, nitrate content and chemical composition. The experiment was conducted in a greenhouse at the Universidade Federal de Santa Catarina, Florianopolis city in the Santa Catarina State (Brazil), from may to july 2004 under a completely randomized design with four replications. The spacing used was 25 x 25 cm for the crops of watercress, chicory and lettuce (cv. Lucy Brown and cv. Regina) and 5 x 5 cm to the rocket. The traits were: number of leaves, nitrate content and chemical composition of vegetables. The lettuce cv. Regina and chicory had higher number of leaves per plant. The watercress had lower water content and higher dry mass of shoots. The largest increase in fresh weight was obtained in chicory, lettuce, cv. Regina. Higher levels of lipids, protein, ash, carbohydrates, calories, fiber and nitrate were obtained from the watercress. The rocket had lower values for the variables fresh and dries the whole plant, shoot and root and leaf number per plant. All cultures showed good visual appearance, low calorie and nitrate levels suitable for human consumption.
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OBJECTIVES To determine the relationship between nasolabial symmetry and esthetics in subjects with orofacial clefts. MATERIAL AND METHODS Eighty-four subjects (mean age 10 years, standard deviation 1.5) with various types of nonsyndromic clefts were included: 11 had unilateral cleft lip (UCL); 30 had unilateral cleft lip and alveolus (UCLA); and 43 had unilateral cleft lip, alveolus, and palate (UCLAP). A 3D stereophotogrammetric image of the face was taken for each subject. Symmetry and esthetics were evaluated on cropped 3D facial images. The degree of asymmetry of the nasolabial area was calculated based on all 3D data points using a surface registration algorithm. Esthetic ratings of various elements of nasal morphology were performed by eight lay raters on a 100 mm visual analog scale. Statistical analysis included ANOVA tests and regression models. RESULTS Nasolabial asymmetry increased with growing severity of the cleft (p = 0.029). Overall, nasolabial appearance was affected by nasolabial asymmetry; subjects with more nasolabial asymmetry were judged as having a less esthetically pleasing nasolabial area (p < 0.001). However, the relationship between nasolabial symmetry and esthetics was relatively weak in subjects with UCLAP, in whom only vermilion border esthetics was associated with asymmetry. CONCLUSIONS Nasolabial symmetry assessed with 3D facial imaging can be used as an objective measure of treatment outcome in subjects with less severe cleft deformity. In subjects with more severe cleft types, other factors may play a decisive role. CLINICAL SIGNIFICANCE Assessment of nasolabial symmetry is a useful measure of treatment success in less severe cleft types.
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OBJECTIVES Assess facial asymmetry in subjects with unilateral cleft lip (UCL), unilateral cleft lip and alveolus (UCLA), and unilateral cleft lip, alveolus, and palate (UCLP), and to evaluate which area of the face is most asymmetrical. METHODS Standardized three-dimensional facial images of 58 patients (9 UCL, 21 UCLA, and 28 UCLP; age range: 8.6-12.3 years) and 121 controls (age range 9-12 years) were mirrored and distance maps were created. Absolute mean asymmetry values were calculated for the whole face, cheek, nose, lips, and chin. One-way analysis of variance, Kruskal-Wallis, and t-test were used to assess the differences between clefts and controls for the whole face and separate areas. RESULTS Clefts and controls differ significantly for the whole face as well as in all areas. Asymmetry is distributed differently over the face for all groups. In UCLA, the nose was significantly more asymmetric compared with chin and cheek (P = 0.038 and 0.024, respectively). For UCL, significant differences in asymmetry between nose and chin and chin and cheek were present (P = 0.038 and 0.046, respectively). In the control group, the chin was the most asymmetric area compared to lip and nose (P = 0.002 and P = 0.001, respectively) followed by the nose (P = 0.004). In UCLP, the nose, followed by the lips, was the most asymmetric area compared to chin, cheek (P < 0.001 and P = 0.016, respectively). LIMITATIONS Despite division into regional areas, the method may still exclude or underrate smaller local areas in the face, which are better visualized in a facial colour coded distance map than quantified by distance numbers. The UCL subsample is small. CONCLUSION Each type of cleft has its own distinct asymmetry pattern. Children with unilateral clefts show more facial asymmetry than children without clefts.
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El transporte del agua en las plantas es impulsado por diferencias de energía libre entre el suelo y la atmósfera, y está regulado por mecanismos biológicos evitadores, como el cierre estomático. La hidratación y la turgencia foliares resultan del equilibrio entre ΨL del apoplasto, el potencial osmótico del simplasto y la elasticidad de los tejidos. Sobre esta base se conjeturó que las interacciones de los mecanismos evitadores del estrés hídrico de la planta tienen un rol clave en la definición de su resistencia a déficit hídrico. Para probar esta hipótesis se construyó un modelo mecanístico basado en las leyes del flujo de savia de Van de Honert, de difusión de Fick, de elasticidad de Hooke, la ecuación de Gardner para el flujo del agua en la rizósfera y el modelo de conductancia estomática (gs) de Buckley. Mediante el modelo se demostró teóricamente que la hidratación y la turgencia foliares dependen de la oferta de agua edáfica (representada por el potencial hídrico del suelo) y de la demanda evaporativa de la atmósfera (representada por la radiación absorbida, la temperatura del aire, la velocidad del viento y el déficit de presión de vapor de la atmósfera). También que los mecanismos evitadores del estrés hídrico -i.e., conductancia hidráulica de la planta, conductancia estomática, elasticidad del tejido y potencial osmótico a turgencia máxima- son todos necesarios para determinar la hidratación y la turgencia foliares. El modelo también demostró que la conductancia hidráulica suelo-hoja (kL) depende de la fracción de agua edáfica transpirable (FTSW) con un patrón de decaimiento sigmoide, a medida que el suelo se seca. Esto implica que las variables que dependen en parte de kL (i.e., gs, transpiración, fotosíntesis y superficie foliar) también dependen de FTSW con el mismo patrón. El modelo se probó experimentalmente a distintos niveles de humedad edáfica (desde déficit hídrico nulo, hasta severo) en cinco variedades de vid y mostró un poder predictivo superior al 90%. En todas las variedades las gs se asociaron linealmente con las kL observadas, al considerar todas las situaciones de déficit hídrico en conjunto, si bien la pendiente de estas relaciones fueron distintas en cada variedad. La contrastación experimental mostró que, en una escala de tiempo de varios meses, las variedades más evitadoras -i.e., Grenache y Cereza- mantuvieron mayor kL, ajuste osmótico y rigidez de los tejidos y una menor pendiente de la relación de gs vs. kL, que las variedades menos evitadoras -i.e., Malbec y Syrah-. La menor pendiente de la relación entre gs y kL, en las variedades más evitadoras, estuvo asociada a una mayor cantidad de estomas, en relación con la cantidad de células epidérmicas. Los variedades más evitadoras bajo déficit hídrico moderado -i.e., con una fracción de agua edáfica transpirable entre 0,6 y 0,4- tuvieron mayor superficie foliar y produjeron más biomasa, favoreciendo raíces profundas y densas, y ahorrando agua. Chardonnay mantuvo una alta hidratación y turgencia a expensas de un alto gasto de agua debido a que privilegiaba una alta kL por sobre el ajuste estomático, por lo que no podría considerarse en forma estricta como muy evitadora.
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Goose grazing on arctic tundra vegetation has shown both positive and negative effects on subsequent foraging conditions. To understand the potential of a density-dependent feedback on herbivore population size, the relation between grazing pressure and future foraging conditions is essential. We studied the effect of increasing grazing pressure of barnacle geese (Branta leucopsis) on Spitsbergen. During the establishment of a breeding colony in the period 1992-2004, the proportion of graminoids decreased in the diet of wild geese, while the percentage of mosses increased. Grazing trials with captive geese in an unexploited area showed a similar shift in diet composition. High-quality food plants were depleted within years and over years. Intake rate declined too and as consequence, metabolisable energy intake rate (MEIR) decreased rapidly with increasing grazing pressure. During three successive years of experimental grazing, MEIR decreased at all levels of grazing pressure and declined below minimal energetic requirements when grazing exceeded natural levels of grazing pressure. This suggests that foraging conditions rapidly decline with increasing grazing pressure in these low-productive habitats. The potential for density-dependent feedbacks on local population increase is discussed.
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back row: Lawrence Massa (video), student trainer Gary Waller, student assistant Thomas Lannon, James Mans, Chris Seychel, Franklin Downing, Thomas Dolan, Patrick Goff, William Brauer, Thomas Stiles, Todd Carlile, James Switzer, Paul Spring, equipment manager Tom Sears, student manager David Marich
middle row: assistant coach Mike Turner, trainer Dan Minert, Alex Sosa, Raymond Dries, Jeffrey Grade, David McIntyre, Douglas May, John Hawkins, Paul Kobylarz, Michael Neff, James McCauley, John DeMartino, Kelly McCrimmon, traveling secretary Howard Colby, head coach John Giordano
front row: Jonathon Elliot, Donald Krussman, Theodore Speers, Joe Milburn, Bradley Tippett, William Reid, Steven Yoxheimer, Mark Chiamp
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back row: student manager David Marich, Stephen Norton, Daniel Goff, James Mans, Daniel Carroll, Douglas Colvin, Bruce Macnab, Bradley Jones, John Bjorkman, Arnold Morrison, Joseph Grusser, Gregory Hudas, student trainer Thomas Brochu
middle row: traveling secretary Howard Colby, Chris Seychel, Thomas Stiles, Paul Spring, Michael Neff, Thomas Dolan, William Brauer, Patrick Goff, David McIntyre, Todd Carlile, Franklin Downing, James Switzer, goalie coach Quenton Rhia
front row: trainer Andy Overmire, assistant coach Mark Miller, Mark Chiamp, Paul Kobylarz, Raymond Dries, Kelly McCrimmon, James McCauley, John DeMartino, Douglas May, Jonathon Elliot, head coach John Giordano, equipment manager Jim Neidert
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Salinity acts to inhibit plant access to soil water by increasing the osmotic strength of the soil solution. As the soil dries, the soil solution becomes increasingly concentrated, further limiting plant access to soil water. An experiment was conducted to examine the effect of salt on plant available water in a heavy clay soil, using a relatively salt tolerant species, wheat ‘Kennedy’, and a more salt sensitive species, chickpea ‘Jimbour’. Sodium chloride was applied to Red Ferrosol at 10 rates from 0 to 3 g/kg. Plants were initially maintained at field capacity. After 3 weeks, plants had become established and watering was ceased. The plants then grew using the water stored in the soil. Once permanent wilting point was reached plants were harvested, and soil water content was measured. The results showed that without salt stress, wheat and chickpea extracted approximately the same amount of water. However, as the salt concentration increased, the ability of chickpea to extract water was severely impaired, while wheat’s ability to extract water was not affected over the range of concentrations examined. Growth of both wheat and chickpea was reduced even from low salt concentrations. Possible explanations for this are that the effect on growth is due to Cl- toxicity and that this occurs at lower concentrations than the osmotic effect of salinity, or that the metabolic demands of maintaining plant water balance and extracting soil water under saline conditions result in reduced growth.
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Effluent from pulp and paper production at the Kemsley mill of Bowaters U.K. Paper Company Limited passes through two treatment stages before its discharge into the Swale estuary. Suspended material removed during treatment is deposited on wasteground as a thin sludge. The solids it contains are mainly wood components lost during pulp production, whilst it also has a high salt content, derived from chemicals used in pulping processes. After deposition the sludge undergoes an ageing process during which it dries out and its salt content is reduced. This ageing can be reproduced and accelerated by improved drainage under controlled conditions. The paper mill sludge was investigated as a casing medium in the culture of Agaricus bisporus (Lange) Pilat, the cultivated mushroom. It was unsuitable up to one year from deposition due largely to the inhibitory effect of its salt content on fruiting. Material eighteen months or more in age gave yields comparable to standard peat casing. Before use as a casing the material must be shredded to a satisfactory structure, neutralised with chalk, and pasteurised to eliminate organisms harmful to the crop. The prepared medium has a high water holding capacity and a structure resilient to management procedures, important requirements of a good casing. A passive movement of salts from the compost to the casing was shown to occur during culture, capable of enhancing the natural decline in cropping if sufficiently great. The ions chloride, potassium, sodium and sulphate were shown to be responsible, their damaging effects being due to high conductivity created in the casing. Studies of elements available during culture suggested phosphate availability in the compost could limit crop potential, whilst iron released by mycelium of A.bisporus in the casing may be utilised by associated micro-organisms.
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Spin coating polymer blend thin films provides a method to produce multiphase functional layers of high uniformity covering large surface areas. Applications for such layers include photovoltaics and light-emitting diodes where performance relies upon the nanoscale phase separation morphology of the spun film. Furthermore, at micrometer scales, phase separation provides a route to produce self-organized structures for templating applications. Understanding the factors that determine the final phase-separated morphology in these systems is consequently an important goal. However, it has to date proved problematic to fully test theoretical models for phase separation during spin coating, due to the high spin speeds, which has limited the spatial resolution of experimental data obtained during the coating process. Without this fundamental understanding, production of optimized micro- and nanoscale structures is hampered. Here, we have employed synchronized stroboscopic illumination together with the high light gathering sensitivity of an electron-multiplying charge-coupled device camera to optically observe structure evolution in such blends during spin coating. Furthermore the use of monochromatic illumination has allowed interference reconstruction of three-dimensional topographies of the spin-coated film as it dries and phase separates with nanometer precision. We have used this new method to directly observe the phase separation process during spinning for a polymer blend (PS-PI) for the first time, providing new insights into the spin-coating process and opening up a route to understand and control phase separation structures. © 2011 American Chemical Society.
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The features of the Furnace Chemical Vapor Deposition (FCVD) method of manufacturing preforms for special optical fibers are considered. It is shown that misalignment of substrate silica tube and furnace hole axes has a negative effect on the quality of fabricated preforms, leading to angular and radial asymmetry of the refractive index profile. Ways of getting rid of this and other disadvantages of the FCVD method are described. Some advantages of the FCVD method over the MCVD method are shown. It was demonstrated that the FCVD method, despite some drawbacks, allows to manufacture high-quality fiber preforms with good symmetry of the refractive index profile, and thus it is promising for fabrication of dispersion, dispersion varying and active fibers. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
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Small-bodied fishes constitute an important assemblage in many wetlands. In wetlands that dry periodically except for small permanent waterbodies, these fishes are quick to respond to change and can undergo large fluctuations in numbers and biomasses. An important aspect of landscapes that are mixtures of marsh and permanent waterbodies is that high rates of biomass production occur in the marshes during flooding phases, while the permanent waterbodies serve as refuges for many biotic components during the dry phases. The temporal and spatial dynamics of the small fishes are ecologically important, as these fishes provide a crucial food base for higher trophic levels, such as wading birds. We develop a simple model that is analytically tractable, describing the main processes of the spatio-temporal dynamics of a population of small-bodied fish in a seasonal wetland environment, consisting of marsh and permanent waterbodies. The population expands into newly flooded areas during the wet season and contracts during declining water levels in the dry season. If the marsh dries completely during these times (a drydown), the fish need refuge in permanent waterbodies. At least three new and general conclusions arise from the model: (1) there is an optimal rate at which fish should expand into a newly flooding area to maximize population production; (2) there is also a fluctuation amplitude of water level that maximizes fish production, and (3) there is an upper limit on the number of fish that can reach a permanent waterbody during a drydown, no matter how large the marsh surface area is that drains into the waterbody. Because water levels can be manipulated in many wetlands, it is useful to have an understanding of the role of these fluctuations.