288 research outputs found
DETECTING EVIDENCE OF NON-COMPLIANCE IN SELF-REPORTED POLLUTION EMISSIONS DATA: AN APPLICATION OF BENFORD'S LAW
The paper introduces Digital Frequency Analysis (DFA) based on Benford's Law as a new technique for detecting non-compliance in self-reported pollution emissions data. Public accounting firms are currently adopting DFA to detect fraud in financial data. We argue that DFA can be employed by environmental regulators to detect fraud in self-reported pollution emissions data. The theory of Benford's Law is reviewed, and statistical justifications for its potentially widespread applicability are presented. Several common DFA tests are described and applied to North Carolina air pollution emissions data in an empirical example.Benford, digital frequency analysis, pollution monitoring, pollution regulation, enforcement, Environmental Economics and Policy, Q25, Q28,
Submillimeter Observations of Dense Clumps in the Infrared Dark Cloud G049.40-00.01
We obtained 350 and 850 micron continuum maps of the infrared dark cloud
G049.40-00.01. Twenty-one dense clumps were identified within G049.40-00.01
based on the 350 micron continuum map with an angular resolution of about 9.6".
We present submillimeter continuum maps and report physical properties of the
clumps. The masses of clumps range from 50 to 600 M_sun. About 70% of the
clumps are associated with bright 24 micron emission sources, and they may
contain protostars. The most massive two clumps show extended, enhanced 4.5
micron emission indicating vigorous star-forming activity. The clump size-mass
distribution suggests that many of them are forming high mass stars.
G049.40-00.01 contains numerous objects in various evolutionary stages of star
formation, from pre-protostellar clumps to HII regions.Comment: 6 pages, 3 figures; accepted for publication in Ap
Detection of OH absorption against PSR B1849+00
We have searched for OH absorption against seven pulsars using the Arecibo
telescope. In both OH mainlines (at 1665 and 1667 MHz), deep and narrow
absorption features were detected toward PSR B1849+00. In addition, we have
detected several absorption and emission features against B33.6+0.1, a nearby
supernova remnant (SNR). The most interesting result of this study is that a
pencil-sharp absorption sample against the PSR differs greatly from the
large-angle absorption sample observed against the SNR. If both the PSR and the
SNR probe the same molecular cloud then this finding has important implications
for absorption studies of the molecular medium, as it shows that the statistics
of absorbing OH depends on the size of the background source. We also show that
the OH absorption against the PSR most likely originates from a small (<30
arcsec) and dense (>10^5 cm^-3) molecular clump.Comment: 12 pages, 8 figures. Accepted for publication in Ap
Key aerodynamic technologies for aircraft engine nacelles
Customer requirements and vision in aerospace dictate that the next generation of civil transport aircraft should have a strong emphasis on increased safety, reduced environmental impact and reduced cost without sacrificing performance. In this context, the School of Mechanical and Aerospace Engineering at the Queen's University of Belfast and Bombardier have, in recent years, been conducting research into some of the key aerodynamic technologies for the next generation of aircraft engine nacelles. Investigations have been performed into anti-icing technology, efficient thrust reversal, engine fire zone safety, life cycle cost and integration of the foregoing with other considerations in engine and aircraft design. A unique correlation for heat transfer in an anti-icing system has been developed. The effect of normal vibration on heat transfer in such systems has been found to be negligible. It has been shown that carefully designed natural blockage thrust reversers without a cascade can reduce aircraft weight with only a small sacrifice in the reversed thrust. A good understanding of the pressure relief doors and techniques to improve the performance of such doors have been developed. Trade off studies between aerodynamics, manufacturing and assembly of engine nacelles have shown the potential for a significant reduction in life cycle cost
Cruciferous vegetable intake is inversely associated with extensive abdominal aortic calcification in elderly women: a cross-sectional study
We have previously shown higher intake of cruciferous vegetables is inversely associated with carotid artery intima-media thickness. To further test the hypothesis that an increased consumption of cruciferous vegetables is associated with reduced indicators of structural vascular disease in other areas of the vascular tree, we aimed to investigate the cross-sectional association between cruciferous vegetable intake and extensive calcification in the abdominal aorta. Dietary intake was assessed, using a food frequency questionnaire, in 684 older women from the Calcium Intake Fracture Outcome Study. Cruciferous vegetables included cabbage, Brussels sprouts, cauliflower and broccoli. Abdominal aortic calcification (AAC) was scored using the Kauppila AAC24 scale on dual energy x-ray absorptiometry (DXA) lateral spine images, and was categorised as ânot extensiveâ (0-5) or âextensiveâ (â„6). Mean age was 74.9 (SD 2.6) y, median cruciferous vegetable intake was 28.2 (IQR 15.0-44.7) g/d, and 128/684 (18.7%) women had extensive AAC scores. Those with higher intakes of cruciferous vegetables ( \u3e 44.6 g/d) were associated with a 46% lower odds of having extensive AAC in comparison to those with lower intakes ( \u3c 15.0 g/d) after adjustment for lifestyle, dietary and cardiovascular disease risk factors (ORQ4 vs Q1=0.54, 95%CI 0.30, 0.97, P=0.036). Total vegetable intake and each of the other vegetable types were not related to extensive AAC (P \u3e 0.05 for all). This study strengthens the hypothesis that higher intake of cruciferous vegetables may protect against vascular calcification
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Pathogenic Parkinsonâs disease mutations across the functional domains of LRRK2 alter the autophagic/lysosomal response to starvation
LRRK2 is one of the most important genetic contributors to Parkinsonâs disease (PD). Point mutations in this gene cause an autosomal dominant form of PD, but to date no cellular phenotype has been consis- tently linked with mutations in each of the functional domains (ROC, COR and Kinase) of the protein product of this gene. In this study, primary fibroblasts from individuals carrying pathogenic mutations in the three central domains of LRRK2 were assessed for alterations in the autophagy/lysosomal pathway using a combination of biochemical and cellular approaches. Mutations in all three domains resulted in alterations in markers for autophagy/lysosomal function compared to wild type cells. These data high- light the autophagy and lysosomal pathways as read outs for pathogenic LRRK2 function and as a marker for disease, and provide insight into the mechanisms linking LRRK2 function and mutations
Ecology: a prerequisite for malaria elimination and eradication
* Existing front-line vector control measures, such as insecticide-treated nets and residual sprays, cannot break the transmission cycle of Plasmodium falciparum in the most intensely endemic parts of Africa and the Pacific
* The goal of malaria eradication will require urgent strategic investment into understanding the ecology and evolution of the mosquito vectors that transmit malaria
* Priority areas will include understanding aspects of the mosquito life cycle beyond the blood feeding processes which directly mediate malaria transmission
* Global commitment to malaria eradication necessitates a corresponding long-term commitment to vector ecolog
Robust estimation of microbial diversity in theory and in practice
Quantifying diversity is of central importance for the study of structure,
function and evolution of microbial communities. The estimation of microbial
diversity has received renewed attention with the advent of large-scale
metagenomic studies. Here, we consider what the diversity observed in a sample
tells us about the diversity of the community being sampled. First, we argue
that one cannot reliably estimate the absolute and relative number of microbial
species present in a community without making unsupported assumptions about
species abundance distributions. The reason for this is that sample data do not
contain information about the number of rare species in the tail of species
abundance distributions. We illustrate the difficulty in comparing species
richness estimates by applying Chao's estimator of species richness to a set of
in silico communities: they are ranked incorrectly in the presence of large
numbers of rare species. Next, we extend our analysis to a general family of
diversity metrics ("Hill diversities"), and construct lower and upper estimates
of diversity values consistent with the sample data. The theory generalizes
Chao's estimator, which we retrieve as the lower estimate of species richness.
We show that Shannon and Simpson diversity can be robustly estimated for the in
silico communities. We analyze nine metagenomic data sets from a wide range of
environments, and show that our findings are relevant for empirically-sampled
communities. Hence, we recommend the use of Shannon and Simpson diversity
rather than species richness in efforts to quantify and compare microbial
diversity.Comment: To be published in The ISME Journal. Main text: 16 pages, 5 figures.
Supplement: 16 pages, 4 figure
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