955 resultados para Implication parentale


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PURPOSE: MicroRNAs (miRNAs) play a global role in regulating gene expression and have important tissue-specific functions. Little is known about their role in the retina. The purpose of this study was to establish the retinal expression of those miRNAs predicted to target genes involved in vision. METHODS: miRNAs potentially targeting important "retinal" genes, as defined by expression pattern and implication in disease, were predicted using a published algorithm (TargetScan; Envisioneering Medical Technologies, St. Louis, MO). The presence of candidate miRNAs in human and rat retinal RNA was assessed by RT-PCR. cDNA levels for each miRNA were determined by quantitative PCR. The ability to discriminate between miRNAs varying by a single nucleotide was assessed. The activity of miR-124 and miR-29 against predicted target sites in Rdh10 and Impdh1 was tested by cotransfection of miRNA mimics and luciferase reporter plasmids. RESULTS: Sixty-seven miRNAs were predicted to target one or more of the 320 retinal genes listed herein. All 11 candidate miRNAs tested were expressed in the retina, including miR-7, miR-124, miR135a, and miR135b. Relative levels of individual miRNAs were similar between rats and humans. The Rdh10 3'UTR, which contains a predicted miR-124 target site, mediated the inhibition of luciferase activity by miR-124 mimics in cell culture. CONCLUSIONS: Many miRNAs likely to regulate genes important for retinal function are present in the retina. Conservation of miRNA retinal expression patterns from rats to humans supports evidence from other tissues that disruption of miRNAs is a likely cause of a range of visual abnormalities.

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Introduction
Unfractionated Heparin (UFH) is used widely in paediatrics. Paediatric specific recommendations for UFH therapy are few, with the majority of recommendations being extrapolated from adult practice. In vitro studies have shown that this practice may be suboptimal. This study aimed to improve the understanding of the impact of age upon UFH response in vivo.

Materials and Methods
This prospective, observational study, conducted in the Paediatric Intensive Care Unit (PICU), included: patients 16 years or younger; treated with UFH of at least 10 U/Kg/hr. Laboratory analysis included: Antithrombin, APTT, Anti-Xa, Anti-IIa and thrombin generation expressed as the Endogenous Thrombin Potential. Results were grouped according to patient age (i.e. < 1, 1-5, 6-10 and 11-16 years).

Results
85 patients received an equivalent mean UFH dose with a median duration of 3 days. Antithrombin levels were decreased compared to age-related norms in children up to 11 years of age. APTT results were comparable across the age-groups. The Anti-Xa results using two different assays showed a trend for lower values in younger children. All children less than one year old recorded Anti-Xa values outside the therapeutic range for heparin therapy, for both assays. There was a trend for decreased Anti-IIa activity in younger children. Endogenous Thrombin Potential showed a significant trend for increased inhibition in older children. In vitro Antithrombin supplementation did not change the Anti-Xa or thrombin generation.

Conclusions
This study confirms that, in vivo, for the same dose of UFH, the anti Xa and anti IIa effect, as well as the inhibition of endogenous thrombin potential is age dependent and that these differences are not purely AT dependent. The implication is that the anticoagulant and antithrombotic effect of a given dose of UFH differs with age. Clinical outcome studies to determine the optimal dosing for each age group are warranted.

Abbreviations
UFH, Unfractionated Heparin; ETP, Endogenous Thrombin Potential; AT, Antithrombin; APTT, Activated Partial Thromboplastin Time

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This paper discusses the relations between extended incidence calculus and assumption-based truth maintenance systems (ATMSs). We first prove that managing labels for statements (nodes) in an ATMS is equivalent to producing incidence sets of these statements in extended incidence calculus. We then demonstrate that the justification set for a node is functionally equivalent to the implication relation set for the same node in extended incidence calculus. As a consequence, extended incidence calculus can provide justifications for an ATMS, because implication relation sets are discovered by the system automatically. We also show that extended incidence calculus provides a theoretical basis for constructing a probabilistic ATMS by associating proper probability distributions on assumptions. In this way, we can not only produce labels for all nodes in the system, but also calculate the probability of any of such nodes in it. The nogood environments can also be obtained automatically. Therefore, extended incidence calculus and the ATMS are equivalent in carrying out inferences at both the symbolic level and the numerical level. This extends a result due to Laskey and Lehner.

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In this article, the authors examine how teachers in four troubled societies – Israel, Cyprus, Northern Ireland and South Africa – understand and implement reconciliation in light of the increasing diversity of these societies. The authors particularly pay attention to a dialogical encounter between reconciliation and inclusion, as they look for ways to contemplate how each might be of mutual benefit in educational theory and practice. In the first part of the article, the authors give an overview of current thinking on reconciliation and its role in education, and suggest that the notion of inclusiveness can enrich it. The context of the research is then provided by looking briefly at the socio-political and educational settings in which the study was conducted, followed by a discussion of the research methodology. The findings from the study are then presented with the main themes identified as arising across the four research locations. These themes concern understandings of reconciliation and inclusion, student diversity, teachers’ challenges, helping students deal with conflict, and teachers’ development. Finally, whilst acknowledging the exploratory nature of these findings, the authors discuss what policy makers, school leaders and teachers might change about policies and practices for reconciliation education in the four settings studied and, by implication, other comparable settings.

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Until now, there has been little empirical evidence that EU Emissions Trading Scheme (ETS) transaction costs are incurred at firm level. The transaction costs (internal costs, capital costs, consultancy and trading costs) incurred by Irish firms under the EU ETS during its pilot phase (2005-2007) were measured and analysed. Evidence for the sources of transaction costs, their magnitude and the distribution of costs shows that these were mainly administrative in nature. Considerable variation in costs was found due to economies of scale, as the costs per tonne of CO2 were lower for participants with larger allocations. For the largest firms - accounting for over half the emissions - average transaction costs were €0.05 per tonne. However, for small firms, average transaction costs were €2.02 - over 18% of the current allowance price. This supports the concerns that transaction costs are excessive for smaller participants. The immediate policy implication is that additional attention will be needed to address different sizes of firms, number of installations per firm, and the size of the initial allocations.

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1. Horizon scanning is an essential tool for environmental scientists if they are to contribute to the evidence base for Government, its agencies and other decision makers to devise and implement environmental policies. The implication of not foreseeing issues that are foreseeable is illustrated by the contentious responses to genetically modified herbicide-tolerant crops in the UK, and by challenges surrounding biofuels, foot and mouth disease, avian influenza and climate change.

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We present the first marine reservoir age and Delta R determination for the island of St. Helena using marine mollusk radiocarbon dates obtained from an historical context of known age. This represents the first marine reservoir a.-c and Delta R determination in the southern Atlantic Ocean within thousands of kilometers of the island. The depletion of C-14 in the shells indicates a rather larger reservoir age for that portion of the surface Atlantic than models indicate. The implication is that upwelling old water along the Namibian coast is transported for a considerable distance, although it is likely to be variable on a decadal timescale. An artilleryman's button, together with other artifacts found in a midden, demonstrate association of the mollusk shells with a narrow historic period of AD 1815-1835.

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The implication of radiation-induced bystander effect (RIBE) for both radiation protection and radiotherapy has attracted significant attention, but a key question is how to modulate the RIBE. The present study found that, when a fraction of glioblastoma cells in T98G population were individually targeted with precise helium particles through their nucleus, micronucleus (MN) were induced and its yield increased non-linearly with radiation dose. After co-culturing with irradiated cells, additional MN could be induced in the non-irradiated bystander cells and its yield was independent of irradiation dose, giving direct evidence of a RIBE. Further results showed that the RIBE could be eliminated by pifithrin-alpha (p53 inhibitor) but enhanced by wortmannin (PI3K inhibitor). Moreover, it was found that nitric oxide (NO) contributed to this RIBE, and the levels of NO of both irradiated cells and bystander cells could be extensively diminished by pifithrin-alpha but insignificantly reduced by wortmannin. Our results indicate that RIBE can be modulated by p53 and PI3K through a NO-dependent and NO-independent pathway, respectively. (C) 2009 Elsevier B.V. All rights reserved.

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Here we provide baseline data on the distribution and abundance of Mola mola within the Irish and Celtic Seas, made during aerial surveys from June to October during 2003-2005. These data were considered in conjunction with concurrent observations of three potential jellyfish prey species found throughout the region: Rhizostoma octopus, Chrysaora hysoscella and Cyanea capillata. A total area of 7850 km(2) was surveyed over the three years with an observed abundance of 68 sunfish giving a density of 0.98 ind/100 km(2). Although modest, these findings highlight that the species is more common than once thought around Britain and Ireland and an order of magnitude greater than the other apex jellyfish predator found in the region, the leatherback turtle (Dermochelys coriacea). furthermore, the distribution of sunfish sightings was inconsistent with the extensive aggregations of Rhizostoma octopus found throughout the study area. The modelled distributions of predator-prey co-occurrence (using data for all three jellyfish species) was less than the observed co-occurrence with the implication that neither jellyfish nor sunfish were randomly distributed but co-occurred more in the same areas than expected by chance. Finally, observed sunfish were typically small (similar to 1 in or less) and seen to either bask or actively swim at the surface.

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Temperature loggers were attached to the carapace of green turtles (Chelonia mydas) at Ascension Island and Cyprus and to loggerhead turtles (Caretta caretta) at Cyprus, in order to record the ambient temperature experienced by individuals during the internesting interval, i.e. the period between consecutive clutches being laid. Internesting intervals were relatively short (10-14 days) and mean ambient temperatures relatively warm (27-28degreesC), compared to previous observations for these species nesting in Japan, although a single internesting interval versus temperature relationship described all the data for these two species from the different areas. The implication is that water temperature has both a common and a profound effect on the length of the internesting interval for these two species: internesting intervals are shorter when the water is warmer. (C) 2002 Elsevier Science Ltd. All rights reserved.

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Two Old English versions of a sunshine prognostication survive in the mid-eleventh century Cambridge, Corpus Christi College 391, p. 713, and in a twelfth-century addition to Oxford, Bodleian Library, Hatton 115, 149v–150r. Among standard predictions promising joy, peace, blossom, abundance of milk and fruit, and a great baptism sent by God, one encounters an enigmatic prophecy which involves camels stealing gold from the ants. These gold-digging ants have a long pedigree, one which links Old English with much earlier literature and indicates the extent to which Anglo-Saxon culture had assimilated traditions of European learning. It remains difficult to say what is being prophesied, however, or to explain the presence of the passage among conventional predictions. Whether the prediction was merely a literary exercise or carried a symbolic implication, it must have originated in an ecclesiastical context. Its mixture of classical learning and vernacular tradition, Greek and Latin, folklore and Christian, implies an author with some knowledge of literary and scholarly traditions.

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Aim. This article is a report of a study conducted to explore the relationship between sources of stress and psychological well-being and to consider how different sources of stress and coping resources might function as moderators and mediators on well-being.


Background. In most research exploring sources of stress and coping in nursing students, stress has been construed as psychological distress. Sources of stress likely to enhance well-being and, by implication, learning have not been considered.


Method. A questionnaire was administered to 171 final year nursing students in 2008. Questions were asked to measure sources of stress when rated as likely to contribute to distress (a hassle) and rated as likely to help one achieve (an uplift). Support, control, self-efficacy and coping style were also measured, along with their potential moderating and mediating effects on well-being, operationalized using the General Health Questionnaire and measures of course and career satisfaction.


Findings. Sources of stress likely to lead to distress were more often predictors of well-being than were sources of stress likely to lead to positive, eustress states, with the exception of clinical placement demands. Self-efficacy, dispositional control and support were important predictors, and avoidance coping was the strongest predictor of adverse well-being. Approach coping was not a predictor of well-being. The mere presence of support appeared beneficial as well as the utility of that support to help a student cope.


Conclusion. Initiatives to promote support and self-efficacy are likely to have immediate benefits for student well-being. In course reviews, nurse educators need to consider how students’ experiences might contribute not just to potential distress, but to eustress as well.

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Galactic bulge planetary nebulae show evidence of mixed chemistry with emission from both silicate dust and polycyclic aromatic hydrocarbons (PAHs). This mixed chemistry is unlikely to be related to carbon dredge-up, as third dredge-up is not expected to occur in the low-mass bulge stars. We show that the phenomenon is widespread and is seen in 30 nebulae out of 40 of our sample, selected on the basis of their infrared flux. Hubble Space Telescope (HST) images and Ultraviolet and Visual Echelle Spectrograph (UVES) spectra show that the mixed chemistry is not related to the presence of emission-line stars, as it is in the Galactic disc population. We also rule out interaction with the interstellar medium (ISM) as origin of the PAHs. Instead, a strong correlation is found with morphology and the presence of a dense torus. A chemical model is presented which shows that hydrocarbon chains can form within oxygen-rich gas through gas-phase chemical reactions. The model predicts two layers, one at A_V~ 1.5, where small hydrocarbons form from reactions with C+, and one at A_V~ 4, where larger chains (and by implication, PAHs) form from reactions with neutral, atomic carbon. These reactions take place in a mini-photon-dominated region (PDR). We conclude that the mixed-chemistry phenomenon occurring in the Galactic bulge planetary nebulae is best explained through hydrocarbon chemistry in an ultraviolet (UV)-irradiated, dense torus.

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The construction industry is inherently hazardous, with a significant number of accidents and incidents occurring, particularly on confined construction sites. This research identifies, clarifies and tabulates the various managerial health and safety issues encountered on confined construction sites, based on a qualitative approach, to aid in the management of the complex health and safety concerns. The methodology is based on qualitative research incorporating case studies, interviews, causal loop diagrams and mind mapping. The key findings in the managerial issues in the management of health and safety on confined construction sites can be summarised as follows; (1) A lack of space, (2) Increased management of site personnel, (3) Overcrowding of the work place. The implication for the industry is that due to the sustained development of urban centres on a global scale, coupled with the increasing complexity of architectural designs, the majority of on-site project management professionals are faced with the onerous task of completing often intricate designs within a limited spatial environment, under strict health and safety parameters. The value of such research is to aid management professionals successfully identify the various managerial issues highlighted, resulting in the successful management of health and safety on a confined construction site.

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The construction industry is inherently risky, with a significant number of accidents and disasters occurring, particularly on confined construction sites. This research investigates and identifies the various issues affecting successful management of health and safety in confined construction sites. The rationale is that identifying the issues would assist the management of health and safety particularly in inner city centres which are mostly confined sites. Using empiricism epistemology, the methodology was based on qualitative research approach by means of multiple case studies in three different geographical locations of Ireland, UK and USA. Data on each case study were collected through individual interviews and focus group discussion with project participants. The findings suggest that three core issues are the underlying factors affecting management of health and safety on confined construction sites. It include, (i) lack of space, (ii) problem of co-ordination and management of site personnel, and (iii) overcrowding of workplace. The implication of this is that project teams and their organisations should see project processes from a holistic point of view, as a unified single system, where quick intervention in solving a particular issue should be the norm, so as not to adversely affect interrelated sequence of events in project operations. Proactive strategies should be devised to mitigate these issues and may include detail project programming, space management, effective constructability review and efficient co-ordination of personnel, plant and materials among others. The value of this research is to aid management and operation of brownfield sites by identifying issues impacting on health and safety management in project process.