994 resultados para 7140-335
Resumo:
In this note, we extend the Goyal and Joshi’s model of collaboration networks in oligopoly to multi-market situations. We examine the incentive of firms to form links and the architectures of the resulting equilibrium networks in this setting. We then present some results on efficient networks.
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Aims. We study the formation and evolution of a failed filament eruption observed in NOAA active region 11121 near the southeast
limb on November 6, 2010.
Methods. We used a time series of SDO/AIA 304, 171, 131, 193, 335, and 94 Å images, SDO/HMI magnetograms, as well as ROSA
and ISOON Hα images to study the erupting active region.
Results. We identify coronal loop arcades associated with a quadrupolar magnetic configuration, and show that the expansion and
cancellation of the central loop arcade system over the filament is followed by the eruption of the filament. The erupting filament
reveals a clear helical twist and develops the same sign of writhe in the form of inverse γ-shape.
Conclusions. The observations support the “magnetic breakout” process in which the eruption is triggered by quadrupolar reconnection
in the corona. We propose that the formation mechanism of the inverse γ-shape flux rope is the magnetohydrodynamic helical
kink instability. The eruption has failed because of the large-scale, closed, overlying magnetic loop arcade that encloses the active
region
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Objectives: To explore children's views on microneedle use for this population, particularly as an alternative approach to blood sampling, in monitoring applications, and so, examine the acceptability of this approach to children.
Methods: Focus groups were conducted with children (aged 10-14 years) in a range of schools across Northern Ireland. Convenience sampling was employed, i.e. children involved in a university-directed community-outreach project (Pharmacists in Schools) were recruited.
Key findings: A total of 86 children participated in 13 focus groups across seven schools in Northern Ireland. A widespread disapproval for blood sampling was evident, with pain, blood and traditional needle visualisation particularly unpopular aspects. In general, microneedles had greater visual acceptability and caused less fear. A patch-based design enabled minimal patient awareness of the monitoring procedure, with personalised designs, e.g. cartoon themes, favoured. Children's concerns included possible allergy and potential inaccuracies with this novel approach; however, many had confidence in the judgement of healthcare professionals if deeming this technique appropriate. They considered paediatric patient education critical for acceptance of this new approach and called for an alternative name, without any reference to 'needles'.
Conclusions: The findings presented here support the development of blood-free, minimally invasive techniques and provide an initial indication of microneedle acceptability in children, particularly for monitoring purposes. A proactive response to these unique insights should enable microneedle array design to better meet the needs of this end-user group. Further work in this area is recommended to ascertain the perspectives of a purposive sample of children with chronic conditions who require regular monitoring. © 2013 Royal Pharmaceutical Society.
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All suicides and related prior attempts occurring in Northern Ireland over two years were analyzed, focusing on number and timing of attempts, method, and mental health diagnoses. Cases were derived from coroner's records, with 90% subsequently linked to associated general practice records. Of those included, 45% recorded at least one prior attempt (with 59% switching from less to more lethal methods between attempt and suicide). Compared with those recording one attempt, those with 2+ attempts were more likely to have used less lethal methods at the suicide (OR = 2.77: 95% CI = 1.06, 7.23); and those using less lethal methods at the attempts were more likely to persist with these into the suicide (OR = 3.21: 0.79, 13.07). Finally, those with preexisting mental problems were more likely to use less lethal methods in the suicide: severe mental illness (OR = 7.88: 1.58, 39.43); common mental problems (OR = 3.68: 0.83, 16.30); and alcohol/drugs related (OR = 2.02: 0.41, 9.95). This analysis uses readily available data to highlight the persisting use of less lethal methods by visible and vulnerable attempters who eventually complete their suicide. Further analysis of such conditions could allow more effective prevention strategies to be developed.
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To provide in-time reactions to a large volume of surveil- lance data, uncertainty-enabled event reasoning frameworks for CCTV and sensor based intelligent surveillance system have been integrated to model and infer events of interest. However, most of the existing works do not consider decision making under uncertainty which is important for surveillance operators. In this paper, we extend an event reasoning framework for decision support, which enables our framework to predict, rank and alarm threats from multiple heterogeneous sources.
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While virtualisation can provide many benefits to a networks infrastructure, securing the virtualised environment is a big challenge. The security of a fully virtualised solution is dependent on the security of each of its underlying components, such as the hypervisor, guest operating systems and storage.
This paper presents a single security service running on the hypervisor that could potentially work to provide security service to all virtual machines running on the system. This paper presents a hypervisor hosted framework which performs specialised security tasks for all underlying virtual machines to protect against any malicious attacks by passively analysing the network traffic of VMs. This framework has been implemented using Xen Server and has been evaluated by detecting a Zeus Server setup and infected clients, distributed over a number of virtual machines. This framework is capable of detecting and identifying all infected VMs with no false positive or false negative detection.
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The study assessed the effect of heating vermiculites on extractability of phosphorus, iron, zinc and manganese with respect to their potential agricultural use. Of these elements, phosphorus was from apatite and monazite that occur as accessory minerals in vermiculites. Vermiculites were heated at 15-800 degrees C and digested by acetic acid for extracting phosphorus and diethylene triamine pentaacetic acid (DTPA) for extracting zinc, iron and manganese. Phosphorus in the extract was analysed by a flow injection method while zinc, iron and manganese were measured by atomic absorption spectrometry. The results showed that heating vermiculites to 400 C enhanced extractability of phosphorus from apatite and monazite to a level of 335 mg kg(-1). Further heating to 800 degrees C reduced extractable phosphorus to less than 75 mg kg(-1). Maximum extractable zinc, iron and manganese found were 2.7, 19.1 and 22.9 mg kg(-1), respectively, values that are beneficial and tolerable by most plants. Thus, it was concluded that heating vermiculites to
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ABSTRACT BODY: To resolve outstanding questions on heating of coronal loops, we study intensity fluctuations in inter-moss portions of active region core loops as observed with AIA/SDO. The 94Å fluctuations (Figure 1) have structure on timescales shorter than radiative and conductive cooling times. Each of several strong 94Å brightenings is followed after ~8 min by a broader peak in the cooler 335Å emission. This indicates that we see emission from the hot component of the 94Å contribution function. No hotter contributions appear, and we conclude that the 94Å intensity can be used as a proxy for energy injection into the loop plasma. The probability density function of the observed 94Å intensity has 'heavy tails' that approach zero more slowly than the tails of a normal distribution. Hence, large fluctuations dominate the behavior of the system. The resulting 'intermittence' is associated with power-law or exponential scaling of the related variables, and these in turn are associated with turbulent phenomena. The intensity plots in Figure 1 resemble multifractal time series, which are common to various forms of turbulent energy dissipation. In these systems a single fractal dimension is insufficient to describe the dynamics and instead there is a spectrum of fractal dimensions that quantify the self-similar properties. Figure 2 shows the multifractal spectrum from our data to be invariant over timescales from 24 s to 6.4 min. We compare these results to outputs from theoretical energy dissipation models based on MHD turbulence, and in some cases we find substantial agreement, in terms of intermittence, multifractality and scale invariance. Figure 1. Time traces of 94A intensity in the inter-moss portions of four AR core loops. Figure 2. Multifractal spectra showing timescale invariance. The four cases of Figure 1 are included.
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Evidence has accumulated of high temperature (> 4 MK) coronal emission in active region cores that corresponds to structures in equilibrium. Other studies have found evidence of evolving loops. We investigate the EUV intensity and temperature variations of short coronal loops observed in the core of NOAA Active Region 11250 on 13 July 2011. The loops, which run directly between the AR opposite polarities, are first detectable in the 94Å band of Fe XVIII, implying an effective temperature ~ 7 MK. The low temperature component of the 94 Å signal is modeled in terms of a linear superposition of the 193 Å and 171 Å signals in order to separate the hot component. After identifying the loops we have used contemporaneous HMI observations to identify the corresponding inter-moss regions, and we have investigated their time evolution in six AIA EUV channels. The results can be separated into two classes. Group 1 (94Å, 335Å, 211Å) is characterized by hotter temperatures (~2-7 MK), and Group 2 (193Å, 171Å, 131Å) by cooler temperatures (0.4 - 1.6 MK). For Group 1 the intensity peaks in the 94Å channel are followed by maxima in the 335 Å channel with a time lag of ~8 min, suggestive of a cooling pattern with an exponential decay. While the 211Å maxima follow those in the 335 Å channel, there is no systematic relation which would indicate a progressive cooling process through the lower temperatures, as has been observed in other investigations. In Group 2 the signals in the 171 and 131Å channels track each other closely, and lag behind the 193Å. In the inter-moss region of the loop the peak temperature and peak emission measure have opposite trends. The hot 94Å brightenings occur in the central part of the loops with maximum temperatures ~7 MK. Subsequently the loops appear to fill with plasma with an emission measure compatible with the 193 Å signal and temperature in the range ~ 1.5-2 MK. Although the exact details of the time evolution are still under investigation, these non static loops show high levels of intermittency in the 94Å signal (please see poster "Intermittent and Scale-Invariant Intensity Fluctuations in Hot Coronal Loops," by Lawrence et al. in this session).
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The preliminary evaluation is described of a new electro-thermal anti-icing/de-icing device for carbon fibre composite aerostructures. The heating element is an electro-conductive carbon-based textile (ECT) by Gorix. Electrical shorting between the structural carbon fibres and the ECT was mitigated by incorporating an insulating layer formed of glass fibre plies or a polymer film. A laboratory-based anti-icing and de-icing test program demonstrated that the film-insulated devices yielded better performance than the glssass fibre insulated ones. The heating capability after impact damage was maintained as long as the ECT fabric was not breached to the extent of causing electrical shorting. A modified structural scarf repair was shown to restore the heating capacity of a damaged specimen.
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Importance Countries with advanced welfare systems are increasingly relying on the input of informal caregivers and there are growing concerns for their mental and physical wellbeing. However, the evidence about the relationship between caregiving and mortality risk is less clear.
Methods A census-based record linkage study with mortality follow-up of thirty-three months. A total of 1,122,779 individuals including 183,842 caregivers, of whom 28.2% (51,927) were providing fifty or more hours caregiving per week.
Results Over thirty-three months of follow-up a total of 29,335 deaths occurred, with 2,443 of these to caregivers. Mortality risk for caregivers was lower than for non-caregivers (HR= 0.72: 95%CI=0.69, 0.75 in the fully adjusted model), and the lower risk was evident even for those providing fifty or more hours of caregiving per week (adjusted Hazard Ratio=0.77: 95%CI=0.71, 0.83 and 0.76: 95%CI=0.69, 0.83 for men and women respectively). There was no evidence that this relationship varied by either age or marital status. Even amongst people with chronic health problems such as poor mental health, caregivers had lower mortality risk than non-caregivers. Caregiving is associated with reduced mortality risk for most causes - for example, the risk of death from Ischaemic Heart Disease for caregivers providing fifty or more hours was 27% and 31% lower for men and for women respectively compared to non-caregivers (HR=0.73: 95%CI=0.60, 0.88 and HR=0.69: 95%CI=0.51, 0.92).
Conclusions This large population-based study confirms that for the majority of caregivers the beneficial effects of caregiving in terms of short-term mortality risk appear to outweigh any negative effects, even amongst people with significant health problems. These results underscore the need for a reappraisal of how caregiving is perceived.
Keywords: caregiving, carers, mortality, longitudinal follow-up.
marital status. Even amongst people with chronic health problems such as poor mental health, caregivers had lower mortality risk than non-caregivers. Caregiving is associated with reduced mortality risk for most causes - for example, the risk of death from Ischaemic Heart Disease for caregivers providing fifty or more hours was 27% and 31% lower for men and for women respectively compared to non-caregivers (HR=0.73: 95%CI=0.60, 0.88 and HR=0.69: 95%CI=0.51, 0.92).
Conclusions This large population-based study confirms that for the majority of caregivers the beneficial effects of caregiving in terms of short-term mortality risk appear to outweigh any negative effects, even amongst people with significant health problems. These results underscore the need for a reappraisal of how caregiving is perceived.