31,001 research outputs found
A Tuner that Accelerates Parameters
We propose a tuner, suitable for adaptive control and (in its discrete-time
version) adaptive filtering applications, that sets the second derivative of
the parameter estimates rather than the first derivative as is done in the
overwhelming majority of the literature. Comparative stability and performance
analyses are presented.Comment: 6 pages, 4 figure
Giving urban policy its 'medical': assessing the place of health in area-based regeneration
How does regeneration affect health and how have successive urban policy evaluations sought to measure such impacts? This article draws on a systematic review of national-level evaluation documentation relating to government-funded, area-based regeneration initiatives in the UK since 1980. The review examined whether health impacts had been intended and, if so, how they had been measured. The process and difficulties of conducting the review raise significant questions about policy formulation and evaluation. Is evidence-based policy possible where evaluations are not stored centrally? In short, a model policy development as 'enlightened' or incremental is hard to sustain where a lack of systematic storage of data means that researchers, policy makers and practitioners may struggle to produce clear answers to important policy questions
Crop protection in organic agriculture - a simple matter?
This report was presented at the UK Organic Research 2002 Conference. Crop protection strategies in organic agriculture and horticulture aim to prevent pest, disease and weed problems through optimisation of the cropping system as a whole. Choice of crops and varieties within the rotation and use of appropriate husbandry practices are critical to the success of the system and direct curative action against pests and diseases is rarely necessary. Research is urgently needed to determine strategies for control of key pests and diseases in organic systems if UK organic agriculture is to expand to meet increasing consumer demand. This paper describes current prevention and control strategies for pests, diseases and weeds in UK organic agriculture and identifies problems that are currently limiting expansion of the industry
Do urban regeneration programmes improve public health and reduce health inequalities? A synthesis of the evidence from UK policy and practice (1980–2004)
Objectives: To synthesise data on the impact on health and key socioeconomic determinants of health and health inequalities reported in evaluations of national UK regeneration programmes.
Data Sources: Eight electronic databases were searched from 1980 to 2004 (IBSS, COPAC, HMIC, IDOX, INSIDE, Medline, Urbadisc/Accompline, Web of Knowledge). Bibliographies of located documents and relevant web sites were searched. Experts and government departmental libraries were also contacted.
Review methods: Evaluations that reported achievements drawing on data from at least two target areas of a national urban regeneration programme in the UK were included. Process evaluations and evaluations reporting only business outcomes were excluded. All methods of evaluation were included. Impact data on direct health outcomes and direct measures of socioeconomic determinants of health were narratively synthesised.
Results: 19 evaluations reported impacts on health or socioeconomic determinants of health; data from 10 evaluations were synthesised. Three evaluations reported health impacts; in one evaluation three of four measures of self reported health deteriorated, typically by around 4%. Two other evaluations reported overall reductions in mortality rates. Most socioeconomic outcomes assessed showed an overall improvement after regeneration investment; however, the effect size was often similar to national trends. In addition, some evaluations reported adverse impacts.
Conclusion: There is little evidence of the impact of national urban regeneration investment on socioeconomic or health outcomes. Where impacts have been assessed, these are often small and positive but adverse impacts have also occurred. Impact data from future evaluations are required to inform healthy public policy; in the meantime work to exploit and synthesise "best available" data is required
Robustness of the nodal d-wave spectrum to strongly fluctuating competing order
We resolve an existing controversy between, on the one hand, convincing
evidence for the existence of competing order in underdoped cuprates, and, on
the other hand, spectroscopic data consistent with a seemingly homogeneous
d-wave superconductor in the very same compounds. Specifically, we show how
short-range fluctuations of the competing order essentially restore the nodal
d-wave spectrum from the qualitatively distinct folded dispersion resulting
from homogeneous coexisting phases. The signatures of the fluctuating competing
order can be found mainly in a splitting of the antinodal quasi-particles and,
depending of the strength of the competing order, also in small induced nodal
gaps as found in recent experiments on underdoped La{2-x}SrxCuO4.Comment: 5 pages, 4 figure
Turbine blade and vane heat flux sensor development, phase 2
The development of heat flux sensors for gas turbine blades and vanes and the demonstration of heat transfer measurement methods are reported. The performance of the heat flux sensors was evaluated in a cylinder in cross flow experiment and compared with two other heat flux measurement methods, the slug calorimeter and a dynamic method based on fluctuating gas and surface temperature. Two cylinders, each instrumented with an embedded thermocouple sensor, a Gardon gauge, and a slug calorimeter, were fabricated. Each sensor type was calibrated using a quartz lamp bank facility. The instrumented cylinders were then tested in an atmospheric pressure combustor rig at conditions up to gas stream temperatures of 1700K and velocities to Mach 0.74. The test data are compared to other measurements and analytical prediction
Digital computer processing of LANDSAT data for North Alabama
Computer processing procedures and programs applied to Multispectral Scanner data from LANDSAT are described. The output product produced is a level 1 land use map in conformance with a Universal Transverse Mercator projection. The region studied was a five-county area in north Alabama
Experimental position-time entanglement with degenerate single photons
We report an experiment in which two-photon interference occurs between
degenerate single photons that never meet. The two photons travel in opposite
directions through our fibre-optic interferometer and interference occurs when
the photons reach two different, spatially separated, 2-by-2 couplers at the
same time. We show that this experiment is analogous to the conventional
Franson-type entanglement experiment where the photons are entangled in
position and time. We measure wavefunction overlaps for the two photons as high
as 94 3%.Comment: Updated to published version, new fig. 4., corrected typo
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Nasal administration of glutamate decarboxylase (GAD65) peptides induces Th2 responses and prevents murine insulin-dependent diabetes.
We previously demonstrated that a spontaneous Th1 response against glutamate decarboxylase (GAD65) arises in NOD mice at four weeks in age and subsequently T cell autoimmunity spreads both intramolecularly and intermolecularly. Induction of passive tolerance to GAD65, through inactivation of reactive T cells before the onset of autoimmunity, prevented determinant spreading and the development of insulin-dependent diabetes mellitus (IDDM). Here, we examined whether an alternative strategy, designed to induce active tolerance via the engagement of Th2 immune responses to GAD65, before the spontaneous onset of autoimmunity, could inhibit the cascade of Th1 responses that lead to IDDM. We observed that a single intranasal administration of GAD65 peptides to 2-3-wk-old NOD mice induced high levels of IgG1 antibodies to GAD65. GAD65 peptide treated mice displayed greatly reduced IFN gamma responses and increased IL-5 responses to GAD65, confirming the diversion of the spontaneous GAD65 Th1 response toward a Th2 phenotype. Consistent with the induction of an active tolerance mechanism, splenic CD4+ (but not CD8+) T cells from GAD65 peptide-treated mice, inhibited the adoptive transfer of IDDM to NOD-scid/scid mice. This active mechanism not only inhibited the development of proliferative T cell responses to GAD65, it also limited the expansion of autoreactive T cell responses to other beta cell antigens (i.e., determinant spreading). Finally, GAD65 peptide treatment reduced insulitis and long-term IDDM incidence. Collectively, these data suggest that the nasal administration of GAD65 peptides induces a Th2 cell response that inhibits the spontaneous development of autoreactive Th1 responses and the progression of beta cell autoimmunity in NOD mice
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