6,482 research outputs found
Participatory Analysis, Monitoring and Evaluation for Fishing Communities: A Manual
While there are many manuals available on participatory rapid appraisal approaches to monitoring and evaluation, there were none easily used by field officers attempting to aid and encourage fishing community level participation in monitoring and evaluating activities of projects and programmes in rural fishing communities.This manual is prepared in cook book fashion with easily followed instructions for 26 participatory monitoring tools to allow use by both local field staff acting as facilitators and directly by community members engaged in the evaluation process
Picosecond electrical spectroscopy using monolithic GaAs circuits
This article describes an experimental apparatus for free-space mm-wave transmission measurements (spectroscopy). GaAs nonlinear transmission lines and sampling circuits are used as picosecond pulse generators and detectors, with planar monolithic bowtie antennas with associated substrate lenses used as the radiating and receiving elements. The received pulse is 270 mV amplitude and 2.4 ps rise time. Through Fourier transformation of the received pulse, 30–250 GHz measurements are demonstrated with <=0.3 dB (rms) accuracy
Radio Observations of the Supernova Remnant Candidate G312.5-3.0
The radio images from the Parkes-MIT-NRAO (PMN) Southern Sky Survey at 4850
MHz have revealed a number of previously unknown radio sources. One such
source, G312.5-3.0 (PMN J1421-6415), has been observed using the
multi-frequency capabilities of the Australia Telescope Compact Array (ATCA) at
frequencies of 1380 MHz and 2378 MHz. Further observations of the source were
made using the Molonglo Observatory Synthesis Telescope (MOST) at a frequency
of 843 MHz. The source has an angular size of 18 arcmin and has a distinct
shell structure. We present the reduced multi-frequency observations of this
source and provide a brief argument for its possible identification as a
supernova remnant.Comment: 5 pages, 5 figures, Accepted for publication in MNRA
The orthogonal fitting procedure for determination of the empirical {\Sigma} - D relations for supernova remnants: application to starburst galaxy M82
The radio surface brightness-to-diameter ({\Sigma} - D) relation for
supernova remnants (SNRs) in the starburst galaxy M82 is analyzed in a
statistically more robust manner than in the previous studies that mainly
discussed sample quality and related selection effects. The statistics of data
fits in log {\Sigma} - log D plane are analyzed by using vertical (standard)
and orthogonal regressions. As the parameter values of D - {\Sigma} and
{\Sigma} - D fits are invariant within the estimated uncertainties for
orthogonal regressions, slopes of the empirical {\Sigma} - D relations should
be determined by using the orthogonal regression fitting procedure. Thus
obtained {\Sigma} - D relations for samples which are not under severe
influence of the selection effects could be used for estimating SNR distances.
Using the orthogonal regression fitting procedure {\Sigma} - D slope {\beta}
\approx 3.9 is obtained for the sample of 31 SNRs in M82. The results of
implemented Monte Carlo simulations show that the sensitivity selection effect
does not significantly influence the slope of M82 relation. This relation could
be used for estimation of distances to SNRs that evolve in denser interstellar
environment, with number denisty up to 1000 particles per cm3 .Comment: 14 pages, 3 figures, no changes, previous version had a typo in
publication related comment, accepted for publication in Ap
Dimensional renormalization: ladders to rainbows
Renormalization factors are most easily extracted by going to the massless
limit of the quantum field theory and retaining only a single momentum scale.
We derive factors and renormalized Green functions to all orders in
perturbation theory for rainbow graphs and vertex (or scattering diagrams) at
zero momentum transfer, in the context of dimensional renormalization, and we
prove that the correct anomalous dimensions for those processes emerge in the
limit D -> 4.Comment: RevTeX, no figure
GAFA Geometric And Functional Analysis FINITE JET DETERMINATION OF LOCAL ANALYTIC CR AUTOMORPHISMS AND THEIR PARAMETRIZATION BY 2-JETS IN THE FINITE
We show that germs of local real-analytic CR automorphisms of a real-analytic hypersurface M in C 2 at a point p ∈ M are uniquely determined by their jets of some finite order at p if and only if M is not Levi-flat near p. This seems to be the first necessary and sufficient result on finite jet determination and the first result of this kind in the infinite type case. If M is of finite type at p, we prove a stronger assertion: the local real-analytic CR automorphisms of M fixing p are analytically parametrized (and hence uniquely determined) by their 2-jets at p. This result is optimal since the automorphisms of the unit sphere are not determined by their 1-jets at a point of the sphere. The finite type condition is necessary since otherwise the needed jet order can be arbitrarily high [Kow1,2], [Z2]. Moreover, we show, by an example, that determination by 2-jets fails for finite type hypersurfaces already in C3. We also give an application to the dynamics of germs of local biholomorphisms of C 2.
Large-N theory of strongly commensurate dirty-bosons: absence of transition in two dimensions
The spherical limit of strongly commensurate dirty-bosons is studied
perturbatively at weak disorder and numerically at strong disorder in two
dimensions (2D). We argue that disorder is not perfectly screened by
interactions, and consequently that the ground state in the effective Anderson
localisation problem always remains localised. As a result there is only a
gapped Mott insulator phase in the theory. Comparisons with other studies and
the parallel with disordered fermions in 2D are discussed. We conjecture that
while for the physical cases N=2 (XY) and N=1 (Ising) the theory should have
the ordered phase, it may not for N=3 (Heisenberg).Comment: 15 pages, 4 figures. Minor typographical errors correcte
The future of farming: the value of ecosystem services in conventional and organic arable land. An experimental approach.
In the current work, a novel, experimental ‘bottom-up’ approach is used to quantify the economic value of ecosystem services (ES) associated with highly modified arable landscapes in Canterbury, New Zealand. First, the role of land management practices in the maintenance and enhancement of ES in agricultural land was investigated by quantifying the economic value of ES at the field level under organic and conventional arable systems. This quantification was based on an experimental approach in contrast with the earlier value transfer methods. Total annual economic value of ES in organic fields ranged from US 19,420 ha⁻¹ yr⁻¹ and that of conventional fields from US 14,570 ha⁻¹ yr⁻¹. The non-market value of ES in organic fields ranged from US 5240 ha⁻¹ yr⁻¹. The range of non-market values of ES in conventional fields was US 332 million and US 192 million and US 65 million and that of conventional area was US $35 million annually. This study demonstrated that arable farming provides a range of ES which can be measured using field experiments based on ecological principles by incorporating a ‘bottom-up’ approach. The work also showed that conventional New Zealand arable farming practices can severely reduce the financial contribution of some of these services in agriculture whereas organic agriculture practices enhance their economic value
Stroke Quality Measures in Mexican Americans and Non-Hispanic Whites
Mexican Americans (MAs) have been shown to have worse outcomes after stroke than non-Hispanic Whites (NHWs), but it is unknown if ethnic differences in stroke quality of care may contribute to these worse outcomes. We investigated ethnic differences in the quality of inpatient stroke care between MAs and NHWs within the population-based prospective Brain Attack Surveillance in Corpus Christi (BASIC) Project (February 2009- June 2012). Quality measures for inpatient stroke care, based on the 2008 Joint Commission Primary Stroke Center definitions were assessed from the medical record by a trained abstractor. Two summary measure of overall quality were also created (binary measure of defect-free care and the proportion of measures achieved for which the patient was eligible). 757 individuals were included (480 MAs and 277 NHWs). MAs were younger, more likely to have hypertension and diabetes, and less likely to have atrial fibrillation than NHWs. MAs were less likely than NHWs to receive tPA (RR: 0.72, 95% confidence interval (CI) 0.52, 0.98), and MAs with atrial fibrillation were less likely to receive anticoagulant medications at discharge than NHWs (RR 0.73, 95% CI 0.58, 0.94). There were no ethnic differences in the other individual quality measures, or in the two summary measures assessing overall quality. In conclusion, there were no ethnic differences in the overall quality of stroke care between MAs and NHWs, though ethnic differences were seen in the proportion of patients who received tPA and anticoagulant at discharge for atrial fibrillation
New measurements of total ionizing dose in the lunar environment
[1] We report new measurements of solar minimum ionizing radiation dose at the Moon onboard the Lunar Reconnaissance Orbiter (LRO) from June 2009 through May 2010. The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument on LRO houses a compact and highly precise microdosimeter whose design allows measurements of dose rates below 1 micro-Rad per second in silicon achieved with minimal resources (20 g, ∼250 milliwatts, and ∼3 bits/second). We envision the use of such a small yet accurate dosimeter in many future spaceflight applications where volume, mass, and power are highly constrained. As this was the first operation of the microdosimeter in a space environment, the goal of this study is to verify its response by using simultaneous measurements of the galactic cosmic ray ionizing environment at LRO, at L1, and with other concurrent dosimeter measurements and model predictions. The microdosimeter measured the same short timescale modulations in the galactic cosmic rays as the other independent measurements, thus verifying its response to a known source of minimum-ionizing particles. The total dose for the LRO mission over the first 333 days was only 12.2 Rads behind ∼130 mils of aluminum because of the delayed rise of solar activity in solar cycle 24 and the corresponding lack of intense solar energetic particle events. The dose rate in a 50 km lunar orbit was about 30 percent lower than the interplanetary rate, as one would expect from lunar obstruction of the visible sky
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