7,195 research outputs found
Letter re: Will Rogers statue
No full textLetter from Farris Campbell, Vice President of the National City Bank of New York, to Amon Carter regarding an unveiling of a statue of Will Rogers
Sedimentary facies and unconformity analysis of some Paleocene-Eocene sections, Marlborough and Campbell Island, New Zealand
No full textThroughout the Late Cretaceous to Eocene, sedimentation in gradually subsiding basins on the passive eastern margin of the micro-continent of Zealandia recorded climatic and paleoceanographic changes in a greenhouse world. One such fundamental change in Southern Ocean circulation is hypothesised to be recorded in a regionally extensive unconformity surface and short-lived lithofacies changes contained within Late Paleocene to Early Eocene sedimentary successions at key sections throughout New Zealand, and investigated here on Campbell Island and in southeastern Marlborough.
On Campbell Island, this oceanographic event is represented by an unconformity between the Late Cretaceous to Late Paleocene Garden Cove Formation and the Early Eocene to Oligocene Tucker Cove Limestone. This unconformity signifies a major lithofacies change from Garden Cove Formation which consists of siliceous mudstone containing fine sand to coarse silt sized siliciclastic grains, pelletal glaucony grains and rare quartz pebbles, to a nannofossil and foraminiferal limestone containing little to no siliciclastic grains comprising the Tucker Cove Limestone. Geochemically this lithofacies change is characterised by a dramatic decrease in terrigenous supply and a shift from siliceous to calcareous productivity, along with a significant concentration of Zr and rare earth elements. Lithofacies at this site are inferred to record possible episodes of ice rafting and eventual unconformity formation by invigorated intermediate depth ocean currents which resulted in winnowing of seafloor sediments and concentration of heavy minerals.
At the distal Mead Stream site in southeastern Marlborough, deposition of bio-siliceous sediments of the Mead Hill Formation and Amuri Limestone was locally disrupted by deposition of the Waipawa Formation, the lateral equivalent of an important hydrocarbon source rock identified in several of New Zealand‟s sedimentary basins. In outcrop, the Waipawa Formation at Mead Stream is characterised by a very distinctive rusty‟ brown fissile appearance, while in thin section, though radiolarians and sponge spicules are common, the overall fine grained nature of the unit makes identification of other components difficult. Geochemical proxies show a significant increase in terrigenous supply in the Waipawa Formation, along with an increase in siliceous productivity concomitant with a decrease in oxygenation at the site. Lithofacies changes through the Late Paleocene at Mead Stream suggest the site lay under a zone of upwelling which resulted in an increase in siliceous productivity during the Late Paleocene.
At the more proximal sites of Muzzle Stream and Kaikoura wharf in southeastern Marlborough, Mead Hill Formation and Amuri Limestone are separated by an unconformity, overlain by Teredo Limestone. The Teredo Limestone is considered to be a lateral equivalent of the Waipawa Formation, but both the base and top of the Teredo Limestone are timetransgressive. This means that at Muzzle Stream the unit is contemporaneous with the Waipawa Formation (Late Paleocene), while at Kaikoura wharf the unit is entirely Early Eocene in age. At these sites, the Teredo Limestone Member of the Amuri Limestone is a calcareous greensand sometimes containing phosphatised limestone clasts and sharks teeth. In thin sections, the unit consists of well sorted, fine to very fine sand sized siliciclastic grains and fine sand sized pelletal and vermicular glaucony set in a calcareous matrix that shows evidence of secondary silicification. Unconformity formation and the subsequent deposition of the overlying Teredo Limestone record a period of invigorated intermediate depth ocean currents that resulted in the transport of siliciclastic grains and glaucony to these bathyal sites. This interpretation is supported by a palinspastic map of the Teredo Limestone that suggests the unit was deposited under different conditions than those responsible for the deposition of the bounding Mead Hill Formation and Amuri Limestone. This map also suggests the Teredo Limestone was deposited as a skin drift‟, here named the Clarence Drift, possibly under the influence of contour currents.
Based on similarities between unconformities and lithofacies changes in Late Paleocene to Early Eocene sedimentary sections and an earlier, well documented event at the Cretaceous/Tertiary boundary in southeastern Marlborough, evidence for a period of enhanced siliceous productivity, invigorated ocean currents and possible episodes of ice rafting is suggested to be consistent with a brief period of Antarctic ice sheet growth during a phase of global cooling in the Late Paleocene.
The possible identification of Antarctic ice sheets, ephemeral though they may have been, not only challenges long held beliefs that the Antarctic continent remained ice free during the early Paleogene greenhouse world but also questions the suggested mechanisms responsible for Antarctic ice sheet growth. The lack of ocean gateways in the Southern Ocean during this time effectively rules out thermal isolation of the Antarctic continent as a driver. Given that this period of ice sheet growth is contemporaneous with a documented period of enhanced global ocean productivity and terrestrial carbon accumulation and related draw down in atmospheric CO2, it is suggested this may represent the driver responsible for brief Antarctic glaciation during this period, though the postulated link requires further investigation
Control and Filtering for Discrete Linear Repetitive Processes with H infty and ell 2--ell infty Performance
No full textRepetitive processes are characterized by a series of sweeps, termed passes, through a set of dynamics defined over a finite duration known as the pass length. On each pass an output, termed the pass profile, is produced which acts as a forcing function on, and hence contributes to, the dynamics of the next pass profile. This can lead to oscillations which increase in amplitude in the pass to pass direction and cannot be controlled by standard control laws. Here we give new results on the design of physically based control laws for the sub-class of so-called discrete linear repetitive processes which arise in applications areas such as iterative learning control. The main contribution is to show how control law design can be undertaken within the framework of a general robust filtering problem with guaranteed levels of performance. In particular, we develop algorithms for the design of an H? and dynamic output feedback controller and filter which guarantees that the resulting controlled (filtering error) process, respectively, is stable along the pass and has prescribed disturbance attenuation performance as measured by and – norms
Teaching Digital Methods:Interview with Richard Rogers
No full textRichard Rogers is the Director of the Digital Methods Initiative, one of Europe’s leading Internet studies research groups. He is Professor of New Media and Digital Culture in the Department of Media Studies at the University of Amsterdam and Academic Director of the Netherlands Research School for Media Studies. Rogers is author of Information Politics on the Web(MIT Press, 2004), Digital Methods (MITPress, 2013) and Doing Digital Methods (Sage, 2019). In this interview, originally conducted for The Pedagogy of Methodological Learning study (Nind & Lewthwaite, 2018) and updated for its publication in Diseña, Rogers speaks about the teaching philosophy behind digital methods, including a particular approach to learning about information design for the humanities and social sciences. He also discusses how he repurposes certain formats traditionally associated with computer science (hackathons) for digital meth-ods ‘data sprints’
Beyond the limits of clinical governance? The case of mental health in English primary care
No full textBackground. Little research attention has been given to attempts to implement organisational initiatives to improve quality of care for mental health care, where there is a high level of indeterminacy and clinical judgements are often contestable. This paper explores recent efforts made at an organisational level in England to improve the quality of primary care for people with mental health problems through the new institutional processes of 'clinical governance'. Methods. Framework analysis, based on the Normalisation Process Model (NPM), of attempts over a five year period to develop clinical governance for primary mental health services in Primary Care Trusts (PCTs). The data come from a longitudinal qualitative multiple case-study approach in a purposive sample of 12 PCTs, chosen to reflect a maximum variety of organisational contexts for mental health care provision. Results. The constant change within the English NHS provided a difficult context in which to attempt to implement 'clinical governance' or, indeed, to reconstruct primary mental health care. In the absence of clear evidence or direct guidance about what 'primary mental health care' should be, and a lack of actors with the power or skills to set about realising it, the actors in 'clinical governance' had little shared knowledge or understanding of their role in improving the quality of mental health care. There was a lack of ownership of 'mental health' as an integral, normalised part of primary care. Conclusion. Despite some achievements in regard to monitoring and standardisation of prescribing practice, mental health care in primary care seems to have so far largely eluded the gaze of 'clinical governance'. Clinical governance in English primary mental health care has not yet become normalised. We make some policy recommendations which we consider would assist in the process normalisation and suggest other contexts to which our findings might apply. © 2008 Gask et al; licensee BioMed Central Ltd
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Folder 3: Court Documents 2, 1979-1982
No full textA letter from the State Bar of Texas rejecting Campbell B. Read's complaint against Mr. Robert M. Phillips
Folder 3: Court Documents 2, 1979-1982
No full textA letter from the State Bar of Texas rejecting Campbell B. Read's complaint against Mr. Robert M. Phillips
Interview with Morgan Callen Rogers, Bath native and author of the novel Red Rub
No full textInterview with Morgan Callen Rogers, Bath native and author of the novel Red Ruby Heart in a Cold Blue Sea
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