869 resultados para Just-in-time
Resumo:
The Rapid Oscillations in the Solar Atmosphere instrument reveals solar atmospheric fluctuations at high frequencies. Spectra of variations of the G-band intensity (IG ) and Ca II K-line intensity (IK ) show correlated fluctuations above white noise to frequencies beyond 300 mHz and 50 mHz, respectively. The noise-corrected G-band spectrum for f = 28-326 mHz shows a power law with exponent -1.21 ± 0.02, consistent with the presence of turbulent motions. G-band spectral power in the 25-100 mHz ("UHF") range is concentrated at the locations of magnetic bright points in the intergranular lanes and is highly intermittent in time. The intermittence of the UHF G-band fluctuations, shown by a positive kurtosis ?, also suggests turbulence. Combining values of IG , IK , UHF power, and ? reveals two distinct states of the solar atmosphere. State 1, including almost all the data, is characterized by low IG , IK , and UHF power and ? ˜ 6. State 2, including only a very small fraction of the data, is characterized by high IG , IK , and UHF power and ? ˜ 3. Superposed epoch analysis shows that the UHF power peaks simultaneously with spatio-temporal IG maxima in either state. For State 1, IK shows 3.5 minute chromospheric oscillations with maxima occurring 21 s after IG maxima implying a 150-210 km effective height difference. However, for State 2 the IK and IG maxima are simultaneous; in this highly magnetized environment sites of G-band and K-line emission may be spatially close together.
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In this paper we demonstrate a new concept in the production of negative hydrogen ions in a low-pressure multicusp discharge. The discharge voltage is modulated to produce a non-Maxwellian, hot-electron plasma during the current pulse, followed by a cool Maxwellian electron plasma in the post discharge. This procedure, of separating in time the required hot and cold electron plasmas required for volume H- production, is called a temporal filter. The time evolution of the electron energy distribution function is measured using the time-resolved second derivative of a Langmuir probe characteristic. Time-resolved measurements of the negative ion density are made using laser photodetachment. The measurements show that the negative ion density in the center of the source, at a gas pressure of 0.07 Pa, increases by a factor of 2 when the discharge is switched off. At this low pressure the average H- beam current extracted from the source, when operated with a discharge current of 1 A in the pulse modulated mode exceeds the H- beam current from a 5 A continuously operated source. The increase in efficiency of the pulsed source is explained in terms of a two-step H- production mechanism.
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Despite being common in epithelial malignancies, the timing of receptor tyrosine kinase (RTK) up-regulation is poorly understood and therefore hampers the identification of the receptor to target for effective treatment. We aimed to determine if RTK expression changes were early events in carcinogenesis. Esophageal adenocarcinoma and its pre-invasive lesion, Barrett's esophagus, were used for immunohistochemical analysis of the RTK panel, EGFR, ErbB2, ErbB3, Met and FGFR2, by utilising a cohort of patients with invasive disease (n = 367) and two cohorts with pre-invasive disease, one cross-sectional (n = 110) and one longitudinal in time (n = 91). The results demonstrated that 51% of esophageal adenocarcinomas over-expressed at least one of the RTK panel; with 21% of these over-expressing multiple receptors. Up-regulation of RTK expression was an early event corresponding with low grade dysplasia development (25% in areas without dysplasia vs. 63% in low grade dysplasia, p
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The prevailing paradigm for researching sensorimotor synchronisation in humans involves finger tapping and temporal accuracy measures. However, many successful sensorimotor synchronisation actions require not only to be 'in time', but also to be in a predefined spatial position. Reaching this spatial position in many everyday actions often exceeds the average amplitude of a finger movement. The aim of this study is to address how people coordinate their movement to be in the right place at the right time when the scale of the movement varies. Does the scale of the movement and accuracy demands of the movement change the ability to accurately synchronise? To address these questions, a sensorimotor synchronisation task with three different inter-beat intervals, two different movement amplitudes and two different target widths was used. Our experiment demonstrated that people use different timing strategies-employing either a movement strategy (varying movement time) or a waiting strategy (keeping movement time constant) for large-scale movements. Those two strategies were found to be equally successful in terms of temporal accuracy and variability (spread of errors). With longer interval durations (2.5 and 3.5 s), variability of sensorimotor synchronisation performance increased (measured as the spread of errors). Analysing the data using the Vorberg and Wing (Handbook of perception and action. Academic Press, New York, pp 181-262, 1996) model shows a need to develop further existing timing models of sensorimotor synchronisation so that they could apply to large-scale movements, where different movement strategies naturally emerge.
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Lung disease in cystic fibrosis (CF) is typified by the development of chronic airways infection culminating in bronchiectasis and progression to end-stage respiratory disease. Pseudomonas aeruginosa, a ubiquitous gram-negative bacteria, is the archetypical CF pathogen and is associated with an accelerated clinical decline. The development and widespread use of chronic suppressive aerosolized antibacterial therapies, in particular Tobramycin Inhalation Solution (TIS), in CF has contributed to reduced lung function decline and improved survival. However, the requirement for the aerosolization of these agents through nebulizers has been associated with increased treatment burden, reduced quality of life and remain a barrier to broader uptake. Tobramycin Inhalation Powder (TIP™) has been developed by Novartis with the express purpose of delivering the same benefits as TIS in a time-effective manner. Administered via the T-326™ (Novartis) Inhaler in four individual 28-mg capsules, TIP can be administered in a quarter of the time of traditional nebulizers and is inherently portable. In clinical studies, TIP has been shown to be safe, result in equivalent or superior reductions in P. aeruginosa sputum density and produce similar improvements in pulmonary function. TIP offers significant advantages in time saving, portability and convenience over traditional nebulized TIS with comparable clinical outcomes for individuals with CF.
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BACKGROUND: We examined the effects of leaving public sector general practitioner (GP) work and of taking a GP position on changes in work-related psychosocial factors, such as time pressure, patient-related stress, distress and work interference with family. In addition, we examined whether changes in time pressure and patient-related stress mediated the association of employment change with changes of distress and work interference with family. METHODS: Participants were 1705 Finnish physicians (60% women) who responded to surveys in 2006 and 2010. Analyses of covariance were conducted to examine the effect of employment change to outcome changes adjusted for gender, age and response format. Mediational effects were tested following the procedures outlined by Baron and Kenny. RESULTS: Employment change was significantly associated with all the outcomes. Leaving public sector GP work was associated with substantially decreased time pressure, patient-related stress, distress and work interference with family. In contrast, taking a position as a public sector GP was associated with an increase in these factors. Mediation tests suggested that the associations of employment change with distress change and work interference with family change were partially explained by the changes in time pressure and patient-related stress. CONCLUSIONS: Our results showed that leaving public sector GP work is associated with favourable outcomes, whereas taking a GP position in the public sector is associated with adverse effects. Primary health-care organizations should pay more attention to the working conditions of their GPs, in particular, to time pressure and patient-related stress.
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A brief review of the occurrence of amplitude modulated structures in space and laboratory plasmas is provided, followed by a theoretical analysis of the mechanism of carrier wave (self-) interaction, with respect to electrostatic plasma modes. A generic collisionless unmagnetized fluid model is employed. Both cold-(zero-temperature) and warm-(finite temperature) fluid descriptions are considered and compared. The weakly nonlinear oscillation regime is investigated by applying a multiple scale (reductive perturbation) technique and a Nonlinear Schrödinger Equation (NLSE) is obtained, describing the evolution of the slowly varying wave amplitude in time and space. The amplitude’s stability profile reveals the possibility of modulational instability to occur under the influence of external perturbations. The NLSE admits exact localized envelope (solitary wave) solutions of bright (pulses) or dark (holes, voids) type, whose characteristics depend on intrinsic plasma parameters. The role of perturbation obliqueness (with respect to the propagation direction), finite temperature and — possibly — defect (dust) concentration is explicitly considered. The relevance of this description with respect to known electron-ion (e-i) as well as dusty (complex) plasma modes is briefly discussed. © 2004 American Institute of Physics
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This monograph develops a theory of events which provides the foundation for a plausible and coherent account of God’s relation to time, and which has independent appeal (independent, that is, of theological considerations). The book is divided into three parts. The first part involves an investigation of those fundamental aspects of time which have important implications for the nature of events, such as whether time is substantival or relational, and whether time is continuous, dense, or discrete. This part also includes a chapter on how these issues relate to different interpretations of the special theory of relativity. The second part involves a defense of the fundamentality of events, and the development of a theory of events in time. The third part considers ways in which we might plausibly conceive of events as eternal entities. This involves an investigation of different ways of characterizing divine eternity, and then an analysis of the possible relations these ways bear to the antecedently developed theory of temporal events. The thought here is that there are certain characteristics of temporal events which can be assimilated to eternity, and that by evaluating the extent to which different theories of divine eternity allow for this assimilation, we will be able to determine which of those theories is most plausible, and therefore which conception of God’s relation to time is most plausible. The basis of this evaluation will be the theory’s ability to coherently account for God’s knowledge of, and interaction with, the created temporal world. One specific issue here is how to account for God’s knowledge of the future free actions of humans (an issue that I address in 'Eternity, Knowledge, and Freedom'), but there are many other difficulties associated with God’s relation to time, such as God’s creation of contingent time, God’s knowledge of what is happening now, God’s dialogue with humans, and God’s causally interacting with the temporal world in general. A successful theory of eternal events, and, in particular, divine events, will provide a framework for dealing with these difficulties.
I have not yet sough a publisher for this work, but intend to do so in 2013, with a target publication date of 2014.
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In this paper we address issues relating to vulnerability to economic exclusion and levels of economic exclusion in Europe. We do so by applying latent class models to data from the European Community Household Panel for thirteen countries. This approach allows us to distinguish between vulnerability to economic exclusion and exposure to multiple deprivation at a particular point in time. The results of our analysis confirm that in every country it is possible to distinguish between a vulnerable and a non-vulnerable class. Association between income poverty, life-style deprivation and subjective economic strain is accounted for by allocating individuals to the categories of this latent variable. The size of the vulnerable class varies across countries in line with expectations derived from welfare regime theory. Between class differentiation is weakest in social democratic regimes but otherwise the pattern of differentiation is remarkably similar. The key discriminatory factor is life-style deprivation, followed by income and economic strain. Social class and employment status are powerful predictors of latent class membership in all countries but the strength of these relationships varies across welfare regimes. Individual biography and life events are also related to vulnerability to economic exclusion. However, there is no evidence that they account for any significant part of the socio-economic structuring of vulnerability and no support is found for the hypothesis that social exclusion has come to transcend class boundaries and become a matter of individual biography. However, the extent of socio-economic structuring does vary substantially across welfare regimes. Levels of economic exclusion, in the sense of current exposure to multiple deprivation, also vary systematically by welfare regime and social class. Taking both vulnerability to economic exclusion and levels of exclusion into account suggests that care should be exercised in moving from evidence on the dynamic nature of poverty and economic exclusion to arguments relating to the superiority of selective over universal social policies.
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Within the Tamm-Dancoff approximation, ab initio approaches describe excitons as packets of electron-hole pairs propagating only forward in time. However, we show that in nanoscale materials excitons and plasmons hybridize, creating exciton-plasmon states where the electron-hole pairs oscillate back and forth in time. Then, as exemplified by the trans-azobenzene molecule and the carbon nanotubes, the Tamm-Dancoff approximation yields errors larger than the accuracy claimed in ab initio calculations. Instead, we propose a general and efficient approach that avoids the Tamm-Dancoff approximation, correctly describes excitons, plasmons, and exciton-plasmon states, and provides a good agreement with experimental results.
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In this paper an evaluation approach to assess the co-ordination of supportive community cancer care is presented. The aim of the study was to identify current gaps in co-ordination of services in a selected region in the province of Ontario, Canada, determine how consistent these gaps were across the province of Ontario, and develop service design considerations for improving the co-ordination of supportive cancer care services in the province of Ontario. The study addressed services required by two populations - clients who had been recently diagnosed and those in the palliative stages of cancer. The evaluation was theory-driven and incorporated evidence from three methods: a systematic literature review, a community case study and a provincial scan. The results revealed the absence of a formal supportive cancer care system and a complex community care system. Supportive cancer care was shown to be delivered by a range of generalist programs that lacked specialisation in addressing the unique needs of cancer clients. In addition, there was no clear evidence of leadership for co-ordinating supportive cancer care, where client care was most often provided by multiple programs at any given point in time. The study generated recommendations to improve co-ordination of supportive cancer care at both the administrative as well as direct care level. © 2004 Elsevier Ireland Ltd. All rights reserved.
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Darwin's On the Origin of Species has led to a theory of evolution with a mass of empirical detail on population genetics below species level, together with heated debate on the details of macroevolutionary patterns above species level. Most of the main principles are clear and generally accepted, notably that life originated once and has evolved over time by descent with modification. Here, I review the fossil and molecular phylogenetic records of the response of life on Earth to Quaternary climatic changes. I suggest that the record can be best understood in terms of the nonlinear dynamics of the relationship between genotype and phenotype, and between climate and environments. 'The origin of species' is essentially unpredictable, but is nevertheless an inevitable consequence of the way that organisms reproduce through time. The process is 'chaotic', but not 'random'. I suggest that biodiversity is best considered as continuously branching systems of lineages, where 'species' are the branch tips. The Earth's biodiversity should thus (1) be in a state of continuous increase and (2) show continuous discrepancies between genetic and morphological data in time and space. © The Palaeontological Association.
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Following on from the Francis Report (2013) the need for a framework of service user involvement is required not just in the Health Service but also in Higher Education. There are wide variances globally on the levels of service user interaction and involvement in healthcare education. Health policy internationally has indicated a move towards developing partnerships with service users but to date this still remains elusive with the majority of user involvement consultative in approach. This paper aims to discuss the Health policy background and the current approaches taken in the involvement of service users in healthcare education.