5,245 research outputs found
Sub-surface damage issues for effective fabrication of large optics
A new ultra precision large optics grinding machine, BoX®has been developed at
Cranfield University. BoX®islocated at the UK's Ultra Precision Surfaces
laboratory at the OpTIC Technium. This machine offers a rapidand economic
solution for grinding large off-axis aspherical and free-form optical
components.This paper presents an analysis of subsurface damage assessments of
optical ground materials produced usingdiamond resin bonded grinding wheels. The
specific materials used, Zerodur®and ULE®are currently understudy for making
extremely large telescope (ELT) segmented mirrors such as in the E-ELT
project.The grinding experiments have been conducted on the BoX®grinding machine
using wheels with grits sizes of76 μm, 46 μm and 25 μm. Grinding process data
was collected using a Kistler dynamometer platform. Thehighest material removal
rate (187.5 mm3/s) used ensures that a 1 metre diameter optic can be ground in
lessthan 10 hours. The surface roughness and surface profile were measured using
a Form Talysurf. The subsurfacedamage was revealed using a sub aperture
polishing process in combination with an etching technique.These results are
compared with the targeted form accuracy of 1 μm p-v over a 1 metre part,
surface roughnessof 50-150 nm RMS and subsurface damage in the range of 2-5 μm.
This process stage was validated on a 400mm ULE®blank and a 1 metre hexagonal Z
Noncanonical spike-related BOLD responses in focal epilepsy
Till now, most studies of the Blood Oxygen Level-Dependent (BOLD) response to interictal epileptic discharges (IED) have assumed that its time course matches closely to that of brief physiological stimuli, commonly called the canonical event-related haemodynamic response function (canonical HRF). Analyses based on that assumption have produced significant response patterns that are generally concordant with prior electroclinical data. In this work, we used a more flexible model of the event-related response, a Fourier basis set, to investigate the presence of other responses in relation to individual IED in 30 experiments in patients with focal epilepsy. We found significant responses that had a noncanonical time course in 37% of cases, compared with 40% for the conventional, canonical HRF-based approach. In two cases, the Fourier analysis suggested activations where the conventional model did not. The noncanonical activations were almost always remote from the presumed generator of epileptiform activity. In the majority of cases with noncanonical responses, the noncanonical responses in single-voxel clusters were suggestive of artifacts. We did not find evidence for IED-related noncanonical HRFs arising from areas of pathology, suggesting that the BOLD response to IED is primarily canonical. Noncanonical responses may represent a number of phenomena, including artefacts and propagated epileptiform activity
Recycling agricultural runoff
The recycling agricultural runoff concept is the storage of excess water from agricultural land and using this water for irrigation of the same land when moisture supplies are low. Coincidentally, the system also recycles pesticides and nutrients, keeping them out of other parts of the environment. The claypan soils of Illinois appear to be best suited for water recycling when surface storage is used. Sandy soils are best suited to interstitial water storage. A review and analysis of literature on irrigation, drainage, reservoirs, pesticides, and nutrients as it pertains to a recycling system is presented. Nutrient and pesticide recycling result in negligible cost or benefits to agricultural crops. There was insufficient information to determine the economic benefit to the environment of this recycling. A model was developed relating irrigation and drainage to crop yield using intermediate variables of soil moisture and air temperature. The model predicted that an acre-ft. of storage would be required per acre of irrigated watershed. The model was not successful at predicting the increase in yield resulting from irrigation and/or drainage. An example economic analysis reveals that under present conditions recycling agricultural runoff is not economically justifiable as a general practice in the claypan region of Illinois.U.S. Geological SurveyU.S. Department of the InteriorOpe
Developments in Catholic churchbuilding in the British Isles 1945-1980.
The period covered by this study has been one of the most intensive in the history of churchbuilding in the three Catholic territories of England and Wales, Scotland, and Ireland. The developments which have occurred have been many and varied, reflecting changes both inside and outside the Church.
Many factors have caused and affected the changes and developments, but none have been more significant than those to be identified with the wider dissemination of Modernist thought and practice in the fields of art and architecture in the British Isles; and with the implementation of the magisterium of the Second Vatican Council which took place half way through the period.
So this study takes a close look at what it considers to be the salient features of these developments, and at their causes and agents, before it surveys the actual developments in churchbuilding themselves.
In the first of the three Sections the nature of church building is considered within a discussion of the nature of 'cultus', and of Catholic worship in the twentieth century. In particular, the repristination of Catholic liturgy by the Liturgical Movement is looked at, with reference to some of its pre- and post-Conciliar effects.
In the second Section the character and purpose of post-war churchbuilding is seen as being very much affected by radical issues arising from cultural, social and ecumenical factors. To assist an assessment of design rationales which took account of these issues, the discussion examines certain influential commentaries and cases.
In the third and final Section a brief consideration of developments in Catholic churchbuilding taking place in the 1930s precedes a closer consideration of those during the period from the end of World. War II upto the Second Vatican Council. A consideration of developments during the period upto the end of the 1960s then precedes a look at what has been happening during the 1970s and early 1980s.
All together, some five hundred examples of Catholic churchbuilding in the British Isles are referred to in varying degrees of detail in order to examine, and form a profile of, post-war developments. These examples are augmented by a much longer list of building projects in the Appendix, together with a list of architectural practises and other information
A Preliminary Evaluation of Deer Behavior and Nontarget Animal Use Associated with the 4-Poster Tickicide Device on Long Island, New York
The 4-Poster device is a host-applied tick control technology. White-tailed deer (Odocoileus virginianus) are attracted to devices by whole kernel corn, and when feeding, each animal contacts rollers that apply an acaricide to the animal\u27s head and neck. The blacklegged tick (Ixodes scapularis), and lone star tick (Amblyomma americanum), are both nuisance and medical pests on Long Island, and deer are a keystone host for both species. By targeting adult ticks where they are most commonly found, deer application is highly effective for concentrating acaricide in key target areas, compared to conventional lawn spraying of pesticides. However, attracting deer to baited stations may have negative impacts including: 1) potential damage to vegetation near the deployed stations in both natural and residential settings; 2) possible increases in deer road crossings, leading to more vehicle collisions; 3) increased deer survivorship or fecundity due to supplemental feeding or reduced tick pressure; and 4) impacts of feeding stations on nontarget wildlife. We are completing the first year of a multi-year project, and report nontarget wildlife use at 4-Poster devices, and deer home ranges for areas with, and without 4-Poster feeding stations. These data will provide management information concerning the collateral effects of deploying 4-Poster devices to reduce tick abundance
Aircraft thrust control
An integrated control system for coaxial counterrotating aircraft propulsors driven by a common gas turbine engine. The system establishes an engine pressure ratio by control of fuel flow and uses the established pressure ratio to set propulsor speed. Propulsor speed is set by adjustment of blade pitch
Cognitive Behaviour Therapy for Health Anxiety:A systematic review and meta-analysis
Background: Health anxiety (HA), or hypochondriasis, is a psychological problem characterized by a preoccupation with the belief that one is physically unwell. A 2007 Cochrane review (Thomson and Page, 2007) found cognitive behavioural therapy (CBT) to be an effective intervention for individuals with HA. Similar findings were reported in a recent meta-analysis (Olatunji et al., 2014), which did not employ a systematic search strategy. The current review aimed to investigate the efficacy of CBT for HA, and to update the existing reviews. Method: A systematic search was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance, including randomized controlled trials that compared CBT with a control condition for people with HA. Five hundred and sixty-seven studies were found in the original search, of which 14 were included in the meta-analysis. Results: Meta-analysis was conducted on 21 comparisons and a large effect size for CBT compared with a control condition was found at post therapy d = 1.01 (95% confidence interval 0.77–1.25), as well as at 6- and 12-month follow-up. Conclusions: This systematic review and meta-analysis provides support for the hypothesis that CBT is an effective intervention for HA when compared with a variety of control conditions, e.g. treatment-as-usual, waiting list, medication, and other psychological therapies
Care transitions for older patients with musculoskeletal disorders: continuity from the providers’ perspective
<p><strong>Introduction</strong>: Care transitions are a common and frequently adverse aspect of health care, resulting in a high-risk period for both care quality and patient safety. Patients who have complex care needs and undergo treatment in multiple care settings, such as older patients with musculoskeletal disorders, may be at higher risk for poor care transitions.</p><p><strong>Methods: </strong>Key informant interviews were used to gather in-depth information on transitional care issues, particularly those which impact informational continuity, from the perspective of a range of health professionals (η=17) in care settings relevant to the care continuum of older patients with hip fractures.</p><p><strong>Results:</strong> Three transitional care themes were identified; medical complexity impacts care trajectories, larger circles of care can be both beneficial and challenging, and a variety of channels and modes are required for meaningful information exchange. Many issues cut across each care setting, and address challenges to informational continuity among and between health care providers, patients, and caregivers.</p><p><strong>Conclusions:</strong> Medical complexity enlarges the circle of care which challenges care continuity. There may be fundamental elements which, regardless of care setting, strengthen transitional care quality. Standardized transitional care processes might help to offset informational discontinuity across care settings as a result of this population's larger circles of care.</p
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