248 research outputs found

    Transition Metal Complexes of Dibenzyl Tetraazamacrocycles

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    Tetraazamacrocycles, cyclic molecules with four nitrogen atoms, have long been known to produce highly stable transition metal complexes. Cross-bridging such molecules with 2-carbon chains has been shown to enhance the stability of these complexes even further, providing enough stability to use the resulting compounds in applications as diverse and demanding as aqueous, green oxidation catalysis all the way to drug molecules injected into humans. Although the stability of these compounds is believed to result from the increased rigidity and topological complexity imparted by the cross-bridge, there is insufficient experimental data to exclude other causes. In this study, standard organic and inorganic synthetic methods were used to produce unbridged dibenzyl tetraazamacrocycle analogues of known cross-bridged tetraazamacrocycles and their transition metal complexes to allow direct comparison of molecules identical except for the cross-bridge. The syntheses of the known tetraazamacrocycles and the novel transition metal complexes were successful with high yields and purity. Initial chemical characterization of the complexes by UV-Visible spectroscopy and cyclic voltammetry shows little difference in electronic properties from bridged versions. Direct comparison studies of the unbridged and bridged compounds’ stabilities remain to be carried out and will shed light on the importance of the cross-bridge to complex robustness

    Partitioning of U, Th and K Between Metal, Sulfide and Silicate, Insights into the Volatile-Content of Mercury

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    During the early stages of the Solar System formation, especially during the T-Tauri phase, the Sun emitted strong solar winds, which are thought to have expelled a portion of the volatile elements from the inner solar system. It is therefore usually believed that the volatile depletion of a planet is correlated with its proximity to the Sun. This trend was supported by the K/Th and K/U ratios of Venus, the Earth, and Mars. Prior to the MESSENGER mission, it was expected that Mercury is the most volatile-depleted planet. However, the Gamma Ray Spectrometer of MESSENGER spacecraft revealed elevated K/U and K/Th ratios for the surface of Mercury, much higher than previous expectations. It is possible that the K/Th and K/U ratios on the surface are not a reliable gauge of the bulk volatile content of Mercury. Mercury is enriched in sulfur and is the most reduced of the terrestrial planets, with oxygen fugacity (fO2) between IW-6.3 and IW-2.6 log units. At these particular compositions, U, Th and K behave differently and can become more siderophile or chalcophile. If significant amounts of U and Th are sequestered in the core, the apparent K/U and K/Th ratios measured on the surface may not represent the volatile budget of the whole planet. An accurate determination of the partitioning of these elements between silicate, metal, and sulfide phases under Mercurian conditions is therefore essential to better constrain Mercury's volatile content and assess planetary formation models

    Crew Resource Management for Automated Teammates (CRM-A)

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    Crew Resource Management (CRM) is the application of human factors knowledge and skills to ensure that teams make effective use of all resources. This includes ensuring that pilots bring in opinions of other teammates and utilize their unique capabilities. CRM was originally developed 40 years ago in response to a number of airline accidents in which the crew was found to be at fault. The goal was to improve teamwork among airline cockpit crews. The notion of "team" was later expanded to include cabin crew and ground resources. CRM has also been adopted by other industries, most notably medicine. Automation research now finds itself faced with similar issues to those faced by aviation 40 years ago: how to create a more robust system by making full use of both the automation and its human operators. With advances in machine intelligence, processing speed and cheap and plentiful memory, automation has advanced to the point that it can and should be treated as a teammate to fully take advantage of its capabilities and contributions to the system. This area of research is known as Human-Autonomy Teaming (HAT). Research on HAT has identified reusable patterns that can be applied in a wide range of applications. These patterns include features such as bi-directional communication and working agreements. This paper will explore the synergies between CRM and HAT. We believe that HAT research has much to learn from CRM and that there are benefits to expanding CRM to cover automation

    Assessment of a self-reported Drinks Diary for the estimation of drinks intake by care home residents: Fluid Intake Study in the Elderly (FISE)

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    Objectives: We evaluated the accuracy of a newly developed self-completed Drinks Diary in care home residents and compared it with direct observation and fluid intake charts. Design: Observational study. Setting: Residential care homes in Norfolk, UK. Participants: 22 elderly people (18 women, mean age 86.6 years SD 8.6, 12 with MMSE scores <27). Measurements: Participants recorded their own drinks intake over 24 hours using the Drinks Diary while care staff used the homes’ usual fluid intake chart to record drinks intake. These records were compared with drinks intake assessed by researcher direct observation (reference method), during waking hours (6am to 10pm), while drinks taken from 10pm to 6am were self-reported and checked with staff. Results: Drinks intake assessed by the Drinks Diary was highly correlated with researcher direct observation (Pearson correlation coefficient r=0.93, p<0.001, mean difference -163ml/day) while few staff-completed fluid charts were returned and correlation was low (r=0.122, p=0.818, mean difference 702ml/day). The Drinks Diary classified 19 of 22 participants correctly as drinking enough or not using both the European Food Safety Authority and US recommendations. Conclusion: The Drinks Diary estimate of drinks intake was comparable with direct observation and more accurate (and reliably completed) than staff records. The Drinks Diary can provide a reliable estimate of drinks intake in elderly care home residents physically and cognitively able to complete it. It may be useful for researchers, care staff and practitioners needing to monitor drinks intake of elderly people, to help them avoid dehydration

    Beyond the Insider—Outsider Perspective: The Study of Religion as a Study of Discourse Construction

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    This essay reflects on contemporary theorizing of religion which embodies an explicit critique of the imperial project, seeing that by most common consent the scholarly disciplinary field of religious studies (history of religion, phenomenology of religion, Religionswissenschaft) is a late nineteenth century invention that coincides with the emergence of anthropology and ethnography as epiphenomena of the colonial project (whether as Orientalism or as exoticism the Other is rendered manageable subjects). The scholarly study of religion is, therefore, simultaneously a study of the history of theory and concept formation, and the social, cultural, and political work performed by such study and theorizing. The metatheory of the study of religion is a main focus of the essay. Alongside that, the essay focuses more pointedly on the concept of discourse, and considers the extraordinary situation where the same methodological vocabulary that functions in religious studies also functions in critical theological studies, which relativizes the division of ‘insider’ and ‘outsider’ perspectives. Yet both are conventionally practised either in isolation from each other as distinct theoretical and disciplinary bounded/defined study fields, or—the other and almost direct opposite—religious studies being performed in the context of theological study, situated in and offered by theological faculties. An overview of recent debates in the field of religious studies serves to highlight the continued struggle to demarcate the boundaries between the study of religion and the study of theology—in some of the recent, very strident debates mainstream religious studies is labelled as nothing more than theology. This contribution, then, aims at a kind of metatheoretical reflection on the study of religion and theology both as discourses that serve mythmaking, identity formation, culturally strategic purposes. That is, from the discourse perspective that is proposed here, it is possible to move beyond the definitional divide between religious studies and theology—even beyond ‘religion’ itself—to focus on the mundanely material practices that constitute that which is called religion. In the way in which the terms are used it is clear that the terminologies themselves bear the imprint of historical social discourses that occasioned the rise of their use. This essay, then, is something of a metacritique of the language of the study of religion—beyond religion, and beyond the study of religion and theology

    Information Display System for Atypical Flight Phase

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    Method and system for displaying information on one or more aircraft flights, where at least one flight is determined to have at least one atypical flight phase according to specified criteria. A flight parameter trace for an atypical phase is displayed and compared graphically with a group of traces, for the corresponding flight phase and corresponding flight parameter, for flights that do not manifest atypicality in that phase
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