988 resultados para 487
Resumo:
Aims. In this paper we report on calculations for energy levels, radiative rates, collision strengths, and effective collision strengths for
transitions among the lowest 25 levels of the n ≤ 5 configurations of H-like Ar xviii.
Methods. The general-purpose relativistic atomic structure package (grasp) andDirac atomic R-matrix code (darc) are adopted for
the calculations.
Results. Radiative rates, oscillator strengths, and line strengths are reported for all electric dipole (E1), magnetic dipole (M1), electric
quadrupole (E2), and magnetic quadrupole (M2) transitions among the 25 levels. Furthermore, collision strengths and effective
collision strengths are listed for all 300 transitions among the above 25 levels over a wide energy (temperature) range up to 800 Ryd
(107.4 K).
Resumo:
The only available parasiticides with a spectrum of action that includes a broad range of helminth and arthropod parasites are the macrocyclic lactones. Designated endectocides, these drugs have action against both endoparasitic nematodes and ectoparasitic arthropods. Unfortunately, the discovery of such drugs is exceedingly rare and there is no evidence that novel endectocidal agents will be identified and developed in the short to medium term. However, the discovery of neuropeptides with motor-modulatory activities in both arthropods and helminths, coupled with recent progress in the characterization of invertebrate neuropeptide receptors, has the potential to propel neuropeptide signalling to the forefront of efforts to develop a novel endectocide.
Resumo:
This paper presents and discusses a social justice strategy that may progress inclusion in schools. The framework for this strategy is grounded in the theoretical discussions by Nancy Fraser and Trevor Gale about distributive, redistributive, and recognitive models of social justice. None of these theoretical frameworks, however, in themselves, offer a clear way forward for marginalised and misrecognised groups, such as disabled children, who need both educational resources and recognition in inclusive classrooms. The authors propose, however, that the work of Fraser and Gale combines into a social justice strategy, which consists of three elements (agency, competency, and diversity, or ‘a, c, d’) that can lead to inclusion. When disabled children are provided with the opportunity to exercise their agency, demonstrate their competence, and transform and affirm notions of diversity, then inclusion is more likely to occur in the classroom. Data from two research projects are presented using this framework to illustrate this argument, and the proposed ‘a, c, d’ social justice strategy towards inclusion.
Resumo:
Purpose – During recent years, the concept of civil society, particularly global civil society, has come to the fore in both academia and policy circles. A key component of recent theoretical and policy research is the attempt to do international comparative research on the meaning of civil society. The purpose of this paper is to argue that the language and the terminology used to describe the agents of civil society are reflective of cultural and historical contexts of societies, have distinct meanings and cannot be used interchangeably.
Design/methodology/approach – In different national contexts, the key agents of civil society are referred to differently; nonprofit sector, voluntary and community sector, third sector and social economy. In comparative studies, scholars often list these concepts to indicate that they recognise that the agents of civil society are referred to differently in different societies. The article offers a socio-historical analysis of each concept. It is concluded that teasing out the differences, as well as the similarities, between the nonprofit sector, voluntary and community sector, third sector and social economy, is crucial to robust comparative research on civil society.
Findings – This paper exposes a number of limitations of each of the terminologies used to describe civil society. They all present a much more limiting notion of civil society than that proposed by the founding fathers. None seem to capture the range of civil associations in any society. Yet, assumptions are made that the terminologies used have similar meanings rather than attempting to clarify and define exactly what is being written or described. This is exacerbated by the interchangeable usage of nonprofit/third sector/community and voluntary sector/social economy. In order to progress beyond culturally specific understandings of civil society, it is necessary to examine the terminology used and how it emanates from a specific cultural and political context. Having a clear understanding of the language used and what it signifies is crucial to robust cross-national comparative research.
Originality/value – This paper examines context specific understandings of civil society and the terminology used to define it; a question not previously addressed. It is hoped that this article will generate much needed further debate on cross-national meanings of civil society.
Resumo:
A novel method for controlling wave energy converters using active bipolar damping is described and compared with current control methods. The performance of active bipolar damping is modelled numerically for two distinct types of wave energy converter and it is found that in both cases the power capture can be significantly increased relative to optimal linear damping. It is shown that this is because active bipolar damping has the potential for providing a quasi-spring or quasi-inertia, which improves the wave energy converter's tuning and amplitude of motion, resulting in the increase in power capture observed. The practical implementation of active bipolar damping is also discussed. It is noted that active bipolar damping does not require a reactive energy store and thereby reduces the cost and eliminates losses due to the cycling of reactive energy. It is also noted that active bipolar damping could be implemented using a single constant pressure double-acting hydraulic cylinder and so potentially represents a simple, efficient, robust and economic solution to the control of wave energy converters.
Resumo:
Recent R-matrix calculations of electron impact excitation rates in Ar IV are used to calculate the emission-line ratio: ratio diagrams (R1, R2), (R1, R3), and (R1, R4), where K1 = I(4711 Å)/I(4740 Å), R2 = I(7238 Å)/I(4711 + 4740 Å), R3 = I(7263 Å)/I(4711 + 4740 Å), and R4 = I(7171 Å)/I(4711 + 4740 Å), for a range of electron temperatures (Te = 5000-20,000 K) and electron densities (Ne = 10-106 cm-3) appropriate to gaseous nebulae. These diagrams should, in principle, allow the simultaneous determination of Te and Ne from measurements of the [Ar IV] lines in a spectrum. Plasma parameters deduced for a sample of planetary nebulae from (R1, R3) and (R1, R4), using observational date obtained with the Hamilton echelle spectrograph on the 3 m Shane Telescope at the Lick Observatory, are found to show excellent internal consistency and to be in generally good agreement with the values of Te and Ne estimated from other line ratios in the echelle spectra. These results provide observational support for the accuracy of the theoretical ratios and, hence, the atomic data adopted in their derivation. In addition, they imply that the 7171 Å line is not as seriously affected by telluric absorption as previously thought. However, the observed values of R2 are mostly larger than the theoretical high-temperature and density limit, which is due to blending of the Ar IV 7237.54 Å line with the strong C II transition at 7236 Å.
Resumo:
The conflict in Northern Ireland known as the Troubles presented numerous challenges for the administration of traditional forms of criminal justice and has led to a variety of adaptations that have been widely discussed in the literature in criminology and transitional justice. The role of Northern Ireland's probation service is often forgotten or ignored in such analyses. This brief article is intended to begin to fill this gap by exploring how the Troubles impacted on probation practice during the Conflict and beyond. In particular, we argue that the 'neutrality stance' taken by probation in the mid-1970s, when officers decided to cease mandated work with individuals charged with 'politically-motivated' offences, has had a lasting impact on the identity and role of probation in the region. The deep immersion into, and engagement with, marginalised communities during this time, facilitated by this neutrality stance, has overlooked implications for probation practice more widely in the United Kingdom and abroad.
Resumo:
The microfilamentous green alga Uronema curvatum is widely distributed along the western and eastern coasts of the north Atlantic Ocean where it typically grows on crustose red algae and on haptera of kelps in subtidal habitats. The placement of this marine species in a genus of freshwater Chlorophyceae had been questioned. Molecular phylogenetic analysis of nuclear-encoded small and large subunit rDNA sequences reveal that U. curvatum is closely related to the ulvophycean order Cladophorales, with which it shares a number of morphological features, including a siphonocladous level of organization and zoidangial development. The divergent phylogenetic position of U. curvatum, sister to the rest of the Cladophorales, along with a combination of distinctive morphological features, such as the absence of pyrenoids, the diminutive size of the unbranched filaments and the discoid holdfast, warrants the recognition of a separate genus, Okellya, within a new family of Cladophorales, Okellyaceae. The epiphytic Urospora microscopica from Norway, which has been allied with U. curvatum, is revealed as a member of the cladophoralean genus Chaetomorpha and is herein transferred to that genus as C. norvegica nom. nov.
Resumo:
Relatively little is known about the biology and ecology of the world's largest (heaviest) bony fish, the ocean sunfish Mola mola, despite its worldwide occurrence in temperate and tropical seas. Studies are now emerging that require many common perceptions about sunfish behaviour and ecology to be re-examined. Indeed, the long-held view that ocean sunfish are an inactive, passively drifting species seems to be entirely misplaced. Technological advances in marine telemetry are revealing distinct behavioural patterns and protracted seasonal movements. Extensive forays by ocean sunfish into the deep ocean have been documented and broad-scale surveys, together with molecular and laboratory based techniques, are addressing the connectivity and trophic role of these animals. These emerging molecular and movement studies suggest that local distinct populations may be prone to depletion through bycatch in commercial fisheries. Rising interest in ocean sunfish, highlighted by the increase in recent publications, warrants a thorough review of the biology and ecology of this species. Here we review the taxonomy, morphology, geography, diet, locomotion, vision, movements, foraging ecology, reproduction and species interactions of M. mola. We present a summary of current conservation issues and suggest methods for addressing fundamental gaps in our knowledge.
Resumo:
Aims To examine the associations between psychological adjustment to Type 2 diabetes and the reported quality and type of relationships with partners. Methods All participants (n = 88) completed a number of questionnaires, including twomeasures of relationship quality: the Dyadic Adjustment Scale and the PersonalAssessment of Intimacy inRelationships Scale, theDiabetesQuality of Life Scale and the ATT-19 (which assesses personal integration of diabetes). Additionally, HbA1c levels were obtained from medical notes. Results Measures of relationship quality significantly contributed to the explanation of two outcomes: personal integration of diabetes and satisfaction with the burden of self-management behaviours. More specifically, the findings demonstrate that a specific aspect of relationship quality—intimacy in recreational activities—is positively associated with the outcomesmentioned above. Conclusions People with Type 2 diabetes who are not taking insulin, who share engagement in physical activities with their partner are more likely to be psychologically well-adjusted to their diagnosis of diabetes.