8,825 research outputs found

    The effect of intravenous amino acids on plasma amino acid concentration during total parenteral nutrition in infants with necrotizing enterocolitis

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    CITATION: Thom, J. C., Victor, T. & Pichanick, A. M. E. 1981. The effect of intravenous amino acids on plasma amino acid concentration during total parenteral nutrition in infants with necrotizing enterocolitis. South African Medical Journal, 59:946-948.The original publication is available at http://www.samj.org.zaPlasma aminograms of infants receiving total parenteral nutrition as part of the treatment for necrotizing enterocolitis were studied. Their ages varied from 2 to 60 days and their mean birth mass was 1621 g (range 760-2550 g). The intravenous administration of amino acids produced changes in plasma amino acid levels corresponding to the concentration of individual amino acid levels in the solution employed: higher levels of amino acids in the infusate produced increased plasma levels, whereas low plasma levels were obtained for amino acids not present or present in small amounts according to the solution used. The infants did not appear to suffer in any way, but the long-term effects still have to be evaluated. Pending further knowledge in this regard it is suggested that plasma amino acid levels should be maintained as near to normal values as possible. This could probably be achieved by the use of amino acid solutions specially formulated according to the amino acid profile of breast milk or the plasma amino acid profile of normal infants.Publisher’s versio

    Effect of Nitrogen Fertilizer on Reproductive Tiller Development in Perennial Ryegrass

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    The objective of this study was to compare reproductive tiller development in two ryegrass (Lolium perenne L.) cultivars, when fertilized with nitrogen. Plots of the cultivars ‘Grasslands Ruanui’ and ‘Ellett’ ryegrass were sown in April 1996. Half of each plot received nitrogen fertilizer (30 kg N/ha) after each grazing by dairy cows from September 1996 to May 1997 and from October 1997 to April 1998. Ryegrass tiller dynamics was monitored from September 1996 to March 1998. The proportion of reproductive tillers in the total tiller population was higher, on average, over the first flowering period (October 1996 to January 1997) for ‘Ellett’ (19.5%) than for ‘Grasslands Ruanui’ (13.0%) ryegrass, and there was no response to nitrogen. Over the second flowering (September 1997 to January 1998), ‘Ellett’ ryegrass slightly increased the proportion of reproductive tillers in response to nitrogen (averaging 20%) while ‘Grasslands Ruanui’ decreased (P \u3c 0.05) the number of reproductive tillers (averaging 6%). Significant cultivar x nitrogen interactions occurred in December 1997 and January 1998 when reproductive tiller number for nitrogen treated plants averaged 24.1% for ‘Ellett’ compared with 7.8% for ‘Grasslands Ruanui’ ryegrass. This work suggests current New Zealand ryegrasses (here represented by ‘Ellett’) may produce more reproductive tillers in response to spring applied nitrogen fertilizer than do older types. To encourage vegetative tillering from the bases of dying reproductive tillers and the likelihood of improved ryegrass persistence, applications of nitrogen fertilizer in early summer are recommended

    The minimum scale of grooving on a recently ruptured limestone fault

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    AbstractFaults have grooves that are formed by abrasion and wear during slip. Recent observations indicate that this grooving is only a large‐scale feature, indicating brittle behavior has a length scale limit. The connection between this scale and earthquake behavior remains limited because no examples exist from a proven seismogenic fault. Here, we address this problem and analyze differences in this scale between lithologies to further our understanding of the underlying mechanics. This study uses samples from the Mt. Vettoretto fault collected after the Norcia earthquake of 2016. We imaged fault topography with a white light interferometer and 10 ÎŒm resolution structure from motion and then calculated a Monte Carlo version of root mean square roughness. We found a minimum scale of grooving of ~100 ÎŒm. In comparing this fault to the Corona Heights fault, we find that this minimum grooving scale is consistent with predictions based on material properties

    Avaliação da avifauna em sistemas agroflorestais com dendĂȘ (Elaeis guianeensis) no municĂ­pio de TomĂ©-Açu (PA).

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    È apresentada uma comparação entre a composição da avifauna de sistemas agroflorestais (SAF) com dendĂȘ, copoeiras e uma monocultura de dendĂȘ ao longo de dois anos no intuito de relatar a funcionalidade dos SAFs na manutenção de aves amazĂŽnicas. Foram registradas 196 espĂ©cies, destas 88 encontradas nos SAFs, 120 na capoeira e 63 na monocultura. Foi observada a ausĂȘncia de espĂ©cies florestais das famĂ­lias, Thamnophilidae, Furnaridae e Tyrannidae no SAF e na monocultura de dendĂȘ, presentes na capoeira. O Ă­ndice de similaridade de Morisita mostra que os SAFs se assemelham mais Ă s monoculturas do que Ă s capoeiras, possivelmente devido ao tempo recente de plantio, onde os SAFs ainda nĂŁo apresentam uma estrutura florestal mais complexa com sub-bosque e dossel. Foi observado um aumento na riqueza de espĂ©cies frutĂ­voras e nectarĂ­voras e na diversidade dos SAFs, possivelmente refletindo o contĂ­nuo desenvolvimento e estruturação deste sistema. Os resultados apresentados mostram que apesar de os SAFs apresentarem uma comunidade de aves em geral distinta da comunidade encontrada nas capoeiras, estas apresentam Ă­ndices de diversidade e riqueza de espĂ©cies semelhantes. A monocultura de dendĂȘ apresentou a menor riqueza e Ă­ndices de diversidade, alĂ©m de apresentar principalmente espĂ©cies insetĂ­voras, onĂ­voras e granĂ­voras na composição de sua avifauna, configurando um ambiente pouco diverso na estrutura da vegetação. Sistemas agroflorestais de dendĂȘ podem vir a contribuir na manutenção da diversidade local de aves florestais amazĂŽnicas, contudo os resultados apontam a necessidade de mais tempo para um melhor desenvolvimento do sistema.Editores tĂ©cnicos: Roberto Porro, Milton Kanashiro, Maria do Socorro Gonçalves Ferreira, Leila Sobral Sampaio e Gladys Ferreira de Sousa

    Understanding Shoot and Root Development

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    Shoot and root development of the grass tiller is presented as a series of events on the tiller axis. Leaf, tiller bud, true stem, and root development are successive events in the life cycle of a single phytomer and the tiller is a co-ordinated series of phytomers, successive phytomers being progressively more advanced than the previous phytomer. In reviewing the individual growth processes of leaf, tiller, true stem, and root formation, fundamental determinants of light and nutrient capture are examined and examples presented to illustrate the link between component processes, plant morphogenesis, and plant performance. An example of the application of this understanding in plant improvement is given

    The Clumping Transition in Niche Competition: a Robust Critical Phenomenon

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    We show analytically and numerically that the appearance of lumps and gaps in the distribution of n competing species along a niche axis is a robust phenomenon whenever the finiteness of the niche space is taken into account. In this case depending if the niche width of the species σ\sigma is above or below a threshold σc\sigma_c, which for large n coincides with 2/n, there are two different regimes. For σ>sigmac\sigma > sigma_c the lumpy pattern emerges directly from the dominant eigenvector of the competition matrix because its corresponding eigenvalue becomes negative. For σ</−sigmac\sigma </- sigma_c the lumpy pattern disappears. Furthermore, this clumping transition exhibits critical slowing down as σ\sigma is approached from above. We also find that the number of lumps of species vs. σ\sigma displays a stair-step structure. The positions of these steps are distributed according to a power-law. It is thus straightforward to predict the number of groups that can be packed along a niche axis and it coincides with field measurements for a wide range of the model parameters.Comment: 16 pages, 7 figures; http://iopscience.iop.org/1742-5468/2010/05/P0500

    A scoping review of female drowning: an underexplored issue in five high-income countries

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    Background: Drowning is a significant public health issue, with females accounting for one third of global drowning deaths. The rate of female drowning has not decreased within high-income countries and presentations to hospital have increased. This scoping review aimed to explore adult female unintentional drowning, including risk factors, clinical treatment and outcomes of females hospitalised for drowning. Methods: A systematic search of the literature following the PRISMA-ScR framework was undertaken. The databases OVID MEDLINE, Embase, CINAHL, OVID Emcare, Web of Science, Informit and Scopus were accessed. Study locations of focus were Australia, Canada, New Zealand, the United Kingdom, and the United States. Studies from January 2003 to April 2019 were included. The quality of evidence of included studies was assessed using GRADE guidelines. Results: The final search results included 14 studies from Australia (n = 4), Canada (n = 1), New Zealand (n = 1), United States (n = 6), United Kingdom (n = 1), and one study reporting data from both Australia and United States. Nine studies reported risk factors for female drowning including age, with the proportion of female drowning incidence increasing with age. Although females are now engaging in risk-taking behaviours associated with drowning that are similar to males, such as consuming alcohol and swimming in unsafe locations, their exposure to risky situations and ways they assess risk, differ. Females are more likely to drown from accidental entry into water, such as in a vehicle during a flood or fall into water. This review found no evidence on the clinical treatment provided to females in hospital after a drowning incident, and only a small number of studies reported the clinical outcomes of females, with inconsistent results (some studies reported better and some no difference in clinical outcomes among females). Conclusion: Adult females are a group vulnerable to drowning, that have lacked attention. There was no single study found which focused solely on female drowning. There is a need for further research to explore female risk factors, the clinical treatment and outcomes of females hospitalised for drowning. This will not only save the lives of females, but also contribute to an overall reduction in drowning
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