991 resultados para Reflecting telescopes.


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Global climate changes during the Quaternary reveal much about broader evolutionary effects of environmental change. Detailed regional studies reveal how evolutionary lineages and novel communities and ecosystems, emerge through glacial bottlenecks or from refugia. There have been significant advances in benthic imaging and dating, particularly with respect to the movements of the British (Scottish) and Irish ice sheets and associated changes in sea level during and after the Last Glacial Maximum (LGM). Ireland has been isolated as an island for approximately twice as long as Britain with no evidence of any substantial, enduring land bridge between these islands after ca 15 kya. Recent biogeographical studies show that Britain's mammal community is akin to those of southern parts of Scandinavia, The Netherlands and Belgium, but the much lower mammal species richness of Ireland is unique and needs explanation. Here, we consider physiographic, archaeological, phylogeographical i.e. molecular genetic, and biological evidence comprising ecological, behavioural and morphological data, to review how mammal species recolonized western Europe after the LGM with emphasis on Britain and, in particular, Ireland. We focus on why these close neighbours had such different mammal fauna in the early Holocene, the stability of ecosystems after LGM subject to climate change and later species introductions.

There is general concordance of archaeological and molecular genetic evidence where data allow some insight into history after the LGM. Phylogeography reveals the process of recolonization, e.g. with respect to source of colonizers and anthropogenic influence, whilst archaeological data reveal timing more precisely through carbon dating and stratigraphy. More representative samples and improved calibration of the ‘molecular clock’ will lead to further insights with regards to the influence of successive glaciations. Species showing greatest morphological, behavioural and ecological divergence in Ireland in comparison to Britain and continental Europe, were also those which arrived in Ireland very early in the Holocene either with or without the assistance of people. Cold tolerant mammal species recolonized quickly after LGM but disappeared, potentially as a result of a short period of rapid warming. Other early arrivals were less cold tolerant and succumbed to the colder conditions during the Younger Dryas or shortly after the start of the Holocene (11.5 kya), or the area of suitable habitat was insufficient to sustain a viable population especially in larger species. Late Pleistocene mammals in Ireland were restricted to those able to colonize up to ca 15 kya, probably originating from adjacent areas of unglaciated Britain and land now below sea level, to the south and west (of Ireland). These few, early colonizers retain genetic diversity which dates from before the LGM. Late Pleistocene Ireland, therefore, had a much depleted complement of mammal species in comparison to Britain.

Mammal species, colonising predominantly from southeast and east Europe occupied west Europe only as far as Britain between ca 15 and 8 kya, were excluded from Ireland by the Irish and Celtic Seas. Smaller species in particular failed to colonise Ireland. Britain being isolated as an island from ca. 8 kya has similar species richness and composition to adjacent lowland areas of northwest continental Europe and its mammals almost all show strongest genetic affinity to populations in neighbouring continental Europe with a few retaining genotypes associated with earlier, western lineages.

The role of people in the deliberate introduction of mammal species and distinct genotypes is much more significant with regards to Ireland than Britain reflecting the larger species richness of the latter and its more enduring land link with continental Europe. The prime motivation of early people in moving mammals was likely to be resource driven but also potentially cultural; as elsewhere, people exploring uninhabited places introduced species for food and the materials they required to survive. It is possible that the process of introduction of mammals to Ireland commenced during the Mesolithic and accelerated with Neolithic people. Irish populations of these long established, introduced species show some unique genetic variation whilst retaining traces of their origins principally from Britain but in some cases, Scandinavia and Iberia. It is of particular interest that they may retain genetic forms now absent from their source populations. Further species introductions, during the Bronze and late Iron Ages, and Viking and Norman invasions, follow the same pattern but lack the time for genetic divergence from their source populations. Accidental introductions of commensal species show considerable genetic diversity based on numerous translocations along the eastern Atlantic coastline. More recent accidental and deliberate introductions are characterised by a lack of genetic diversity other than that explicable by more than one introduction.

The substantial advances in understanding the postglacial origins and genetic diversity of British and Irish mammals, the role of early people in species translocations, and determination of species that are more recently introduced, should inform policy decisions with regards to species and genetic conservation. Conservation should prioritise early, naturally recolonizing species and those brought in by early people reflecting their long association with these islands. These early arrivals in Britain and Ireland and associated islands show genetic diversity that may be of value in mitigating anthropogenic climate change across Europe. In contrast, more recent introductions are likely to disturb ecosystems greatly, lead to loss of diversity and should be controlled. This challenge is more severe in Ireland where the number and proportion of invasive species from the 19th century to the present has been greater than in Britain.

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We describe the Pan-STARRS Moving Object Processing System (MOPS), a modern software package that produces automatic asteroid discoveries and identifications from catalogs of transient detections from next-generation astronomical survey telescopes. MOPS achieves >99.5% efficiency in producing orbits from a synthetic but realistic population of asteroids whose measurements were simulated for a Pan-STARRS4-class telescope. Additionally, using a nonphysical grid population, we demonstrate that MOPS can detect populations of currently unknown objects such as interstellar asteroids. MOPS has been adapted successfully to the prototype Pan-STARRS1 telescope despite differences in expected false detection rates, fill-factor loss, and relatively sparse observing cadence compared to a hypothetical Pan-STARRS4 telescope and survey. MOPS remains highly efficient at detecting objects but drops to 80% efficiency at producing orbits. This loss is primarily due to configurable MOPS processing limits that are not yet tuned for the Pan-STARRS1 mission. The core MOPS software package is the product of more than 15 person-years of software development and incorporates countless additional years of effort in third-party software to perform lower-level functions such as spatial searching or orbit determination. We describe the high-level design of MOPS and essential subcomponents, the suitability of MOPS for other survey programs, and suggest a road map for future MOPS development.

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We present initial results from observations and numerical analyses aimed at characterizing the main-belt comet P/2012 T1 (PANSTARRS). Optical monitoring observations were made between 2012 October and 2013 February using the University of Hawaii 2.2 m telescope, the Keck I telescope, the Baade and Clay Magellan telescopes, Faulkes Telescope South, the Perkins Telescope at Lowell Observatory, and the Southern Astrophysical Research Telescope. The object's intrinsic brightness approximately doubles from the time of its discovery in early October until mid-November and then decreases by ~60% between late December and early February, similar to photometric behavior exhibited by several other main-belt comets and unlike that exhibited by disrupted asteroid (596) Scheila. We also used Keck to conduct spectroscopic searches for CN emission as well as absorption at 0.7 μm that could indicate the presence of hydrated minerals, finding an upper limit CN production rate of Q CN <1.5 × 1023 mol s-1, from which we infer a water production rate of Q_H_2O100 Myr and is unlikely to be a recently implanted interloper from the outer solar system, while a search for potential asteroid family associations reveals that it is dynamically linked to the ~155 Myr old Lixiaohua asteroid family. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration, and made possible by the generous financial support of the W. M. Keck Foundation, the Magellan Telescopes located at Las Campanas Observatory, Chile, and the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia, e Inovação (MCTI) da República Federativa do Brasil, the U.S. National Optical Astronomy Observatory (NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU).

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We report photometric observations for comet C/2012 S1 (ISON) obtained during the time period immediately after discovery (r = 6.28 AU) until it moved into solar conjunction in mid-2013 June using the UH2.2 m, and Gemini North 8 m telescopes on Mauna Kea, the Lowell 1.8 m in Flagstaff, the Calar Alto 1.2 m telescope in Spain, the VYSOS-5 telescopes on Mauna Loa Hawaii and data from the CARA network. Additional pre-discovery data from the Pan STARRS1 survey extends the light curve back to 2011 September 30 (r = 9.4 AU). The images showed a similar tail morphology due to small micron sized particles throughout 2013. Observations at submillimeter wavelengths using the James Clerk Maxwell Telescope on 15 nights between 2013 March 9 (r = 4.52 AU) and June 16 (r = 3.35 AU) were used to search for CO and HCN rotation lines. No gas was detected, with upper limits for CO ranging between 3.5-4.5 × 1027 molecules s-1. Combined with published water production rate estimates we have generated ice sublimation models consistent with the photometric light curve. The inbound light curve is likely controlled by sublimation of CO2. At these distances water is not a strong contributor to the outgassing. We also infer that there was a long slow outburst of activity beginning in late 2011 peaking in mid-2013 January (r ~ 5 AU) at which point the activity decreased again through 2013 June. We suggest that this outburst was driven by CO injecting large water ice grains into the coma. Observations as the comet came out of solar conjunction seem to confirm our models.

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Twenty years on from the 1994 cease-fires, Northern Ireland is a markedly safer place for children and young people to grow up. However, for a significant number, growing up in post-conflict Northern Ireland has brought with it continued risks and high levels of marginalization. Many young people growing up on the sharp edge of the transition have continued to experience troubling levels of poverty, lower educational attainment, poor standards of childhood health, and sustained exposure to risk-laden environments. Reflecting on interdisciplinary research carried out since the start of the “transition” to peace, this article emphasizes the impact that embedded structural inequalities continue to have on the social, physical, mental, and emotional well-being of many children and young people. In shining a light on the enduring legacy of the conflict, this article moves to argue that greater attention needs to be given to the ongoing socioeconomic factors that result in limited lifetime opportunities, marginalization, and sustained poverty for many young people growing up in “peacetime” Northern Ireland.

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Although the international obligations and institutional frameworks for disaster response are not yet settled, as evidenced by the International Law Commission’s work on the protection of persons in the event of disasters and the on-going promotion of disaster laws by the Red Cross Movement; the diverse source and nature of such initiatives suggests that the international community is engaged in a process of norm creation, elaboration and interpretation reflecting a desire for legal clarity in humanitarian operations. Situated within the framework of transnational law, this paper argues that an acquis humanitaire, based on the principle of humanity, encapsulates the evolving body of law and practice specifically relating to the protection of persons in times of humanitarian crisis in both armed conflicts and natural or human-made disasters. Reflecting the non-traditional, non-statist, dynamic and normative basis of transnational legal process, as elaborated by Harold Koh, the constant flow of ideas and principles between the national, regional and international spheres provides an analytical framework for the on-going transnational dialogues on the social, political and legal internalization of humanitarian norms. Drawing on the internalization of humanitarian norms within the United Kingdom, this paper concludes that as the international community examines the codification of a universal legal framework for the protection of persons in the event of disasters it is necessary to understand the transnational process of interpretation and internalization of humanitarian norms, and how this may vary across different regions and countries.

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The question of whether and to what extent sovereignty has been transferred to the European Union (EU) from its Member States remains a central debate within the EU and is interlinked with issues such as Kompetenz-Kompetenz, direct effect and primacy. Central to any claim to sovereignty is the principle of primacy, which requires that Member States uphold EU law over national law where there is a conflict. However, limitations to primacy can traditionally be found in national jurisprudence and the Maastricht Treaty introduced a possible EU limitation with the requirement that the EU respect national identities of Member States. The Lisbon Treaty provided only minimal further support to the principle of primacy whilst simultaneously developing the provision on national identities, now found within Article 4(2) TEU. There are indications from the literature, national constitutional courts and the Court of Justice of the EU that the provision is gathering strength as a legal tool and is likely to have a wider scope than the text might indicate. In its new role, Article 4(2) TEU bolsters the Member States’ claim to sovereignty and the possibility to uphold aspects crucial to them in conflict with EU law and the principle of primacy. Consequently, it is central to the relationship between the constitutional courts of the Member States and the CJEU, and where the final elements of control remain in ‘hard cases’. However, it does so as part of EU law, thereby facilitating the evasion of direct fundamental conflicts and reflecting the concept of constitutional pluralism.

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Infrared water line emission from protoplanetary disks, recently observed by the Spitzer and Herschel space telescopes, is thought to trace the surface layer of the inner to outer regions of the disks. We have modelled the water abundance profile and line emission, especially focusing on the effects of dust size growth and turbulent mixing. Comparison between model calculations and observations suggests a small grain model with turbulent mixing is preferred. Copyright © International Astronomical Union 2014.

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This paper describes patterns and processes of recent migration in Northern Ireland. A conceptual approach is provided for spatial understandings of migration in new destinations, and the role of context is explored with regard to migration to a divided society. Recent migration to Northern Ireland is characterised and the geography of migrant residences evidenced in the 2011 Census is presented. Key patterns include the rural nature of migration in Northern Ireland, variation among migrant groups, and the spatial concentration of migrant communities. This exploration of spatial patterns is expanded on through a consideration of the processes of migration and diversification according to the themes of Finding Housing and Neighbourhood Interactions. In conclusion we explore the implications of the data presented, reflecting on spatial problems and spatial solutions in diversifying Northern Ireland.

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While substantive EU non-discrimination law has been harmonized in great detail, the enforcement regime for EU non-discrimination law consists merely of a few isolated elements. Thus, the pursuit of unity through harmonization in substantive EU law is accompanied by considerable regulatory autonomy for Member States in securing the efficiency of those laws, reflecting the diversity of national enforcement regimes, and resulting in twenty-seven different national models for enforcing discrimination law in labour markets. This article pursues two connected arguments through a comparison of rules for enforcing non-discrimination law in labour markets in Britain and Italy. First, it argues that enforcing non-discrimination law in labour markets is best achieved when responsive governance, repressive regulation and mainstreaming equality law are combined. Second, the article submits that diversity of national legal orders within the EU is not necessarily detrimental, as it offers opportunities for mutual learning across legal systems.The notion of mutual learning across systems is proposed in order to analyse the transnational migration of legal ideas within the EU. Such migration has been criticized in debates about the ‘transplantation’ of legal concepts or legal irritation through foreign legal ideas, in particular by comparative labour lawyers. However, EU harmonization policies in the field of non-discrimination law aim to impact on national labour laws. The article develops the notion of mutual learning across legal systems in order to establish conditions for transnational migration of legal ideas, and demonstrates the viability of these concepts by applying them to the field of non-discrimination law

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Care Planning in Children and Young People's Nursing addresses a selection of the most common concerns that arise when planning care for infants, children and young people within the hospital and community setting. Clear and detailed, this text reflects both the uniqueness and diversity of contemporary children's nursing and utilizes images and case studies to provide a holistic insight into the practice of care planning through the reporting of best available evidence and current research, policy and education.

Divided into sections for ease of reference, Care Planning in Children and Young People’s Nursing explores both the theory and practice of care planning. Chapters on the principles of care planning include issues such as managing risk, safeguarding children, ethical and legal implications, integrated care pathways, interprofessional assessment, and invaluable parent perspectives. Additional chapters on the application of planning care examine the practical aspects of a wide range of specific conditions including cystic fibrosis, obesity, cardiac/renal failure and HIV/AIDS. Each chapter is interactive, with questions, learning activities and points for discussion creating an engaging and enquiry-based learning approach.

Care Planning in Children and Young People’s Nursing is a definitive resource, reflecting innovative practice which is suitable for undergraduate and postgraduate nurse education.

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A new type of active frequency selective surface (AFSS) is proposed to realise a voltage controlled bi-state (transparent and reflecting) response at the specified frequencies. The bi-state switching is achieved by combining a passive array of interleaved spiral slots in conducting screens and active dipole arrays with integrated pin diodes at the opposite sides of a thin dielectric substrate. Simulation results show that such active surfaces have high isolation between the transparency and reflection states, while retaining the merits of substantially sub-wavelength response of the unit cell and large fractional bandwidths (FBWs) inherent to the original passive interwoven spiral arrays. Potential applications include reconfigurable and controllable electromagnetic architecture of buildings.

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Reconfigurable bi-state interwoven spiral FSSs are explored in this work. Their switching capability is realized by pin diodes that enable the change of the electromagnetic response between transparent and reflecting modes at the specified frequencies in both singly and dual polarised unit cell configurations. The proposed topologies are single layer FSS with their elements acting also as dc current carrying conductors supplying the bias signal for switching pin diodes between the on and off states, thus avoiding the need of external bias lines that can cause parasitic resonances and affect the response at oblique incidence. The presented simulation results show that such active FSSs have potentially good isolation between the transmission and reflection states, while retaining the substantially subwavelength response of the unit cell with large fractional bandwidths (FBWs) inherent to the original passive FSSs.

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This article is written to celebrate the fine contribution and constant optimism of Louk Hulsman to the debate about penal abolition, the rethinking of popular and political discourses on ‘crime’, and the institutionalised responses of the ‘criminal justice system’. Reflecting on his experiences of incarceration and on his critical analysis of the political economic relations of power, Louk Hulsman talked of the defining ‘moment of abolition’ – his reading of Thomas Mathiesen’s ground-breaking text, The Politics of Abolition. Having considered the key elements of Louk Hulsman’s work and its critical challenge to the criminological enterprise, the article explores the apparent political contradiction in campaigning for humane conditions while seeking abolition within the context of an ever-expanding, global prison-industrial complex.

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Summary: Social work is a discipline that focuses on the person-in-the-environment. However, the social domains of influence have traditionally received more attention from the profession compared with the impact of the natural world on human well-being. With the development of ecological theories, and growing threats to the environment, this gap has been addressed and now the notion of eco-social work is attracting more interest. This article builds on this corpus of work by exploring, and augmenting, the thinking of the philosopher, David Abram, and his phenomenological investigation of perception, meaning, embodiment, language and Indigenous experience. The implications for eco-social work are then addressed.

Findings: The development of Abram’s philosophical thesis is charted by reviewing his presentation of the ideas of the European phenomenologists, Edmund Husserl and Maurice Merleau-Ponty. It is argued that Abram uses phenomenology to explore the character of perception and the sensual foundations of language which, in Indigenous cultures, are connected with the natural world. A gap in Abram’s thinking is then revealed showing the need to set human perception and language within an understanding of power. Overall, this re-worked thesis is underpinned by a meta-narrative in which ecology engages with philosophy, psychology and Indigenous experience.

Applications: By grounding such ideas in Slavoj Žižek’s construct of the sensuous event, three applications within social work are evinced, namely: (i) reflecting on the sensuous event in social work education; (ii) rekindling the sensuous event with Indigenous Peoples; and (iii) instigating the sensuous event with non-Indigenous populations.