1,059 research outputs found
Stochastic Background Search Correlating ALLEGRO with LIGO Engineering Data
We describe the role of correlation measurements between the LIGO
interferometer in Livingston, LA, and the ALLEGRO resonant bar detector in
Baton Rouge, LA, in searches for a stochastic background of gravitational
waves. Such measurements provide a valuable complement to correlations between
interferometers at the two LIGO sites, since they are sensitive in a different,
higher, frequency band. Additionally, the variable orientation of the ALLEGRO
detector provides a means to distinguish gravitational wave correlations from
correlated environmental noise. We describe the analysis underway to set a
limit on the strength of a stochastic background at frequencies near 900 Hz
using ALLEGRO data and data from LIGO's E7 Engineering Run.Comment: 8 pages, 2 encapsulated PostScript figures, uses IOP class files,
submitted to the proceedings of the 7th Gravitational Wave Data Analysis
Workshop (which will be published in Classical and Quantum Gravity
Progress on stochastic background search codes for LIGO
One of the types of signals for which the LIGO interferometric gravitational
wave detectors will search is a stochastic background of gravitational
radiation. We review the technique of searching for a background using the
optimally-filtered cross-correlation statistic, and describe the state of plans
to perform such cross-correlations between the two LIGO interferometers as well
as between LIGO and other gravitational-wave detectors, in particular the
preparation of software to perform such data analysis.Comment: 7 pages, 1 encapsulated PostScript figure, uses IOP class files,
submitted to the proceedings of the 4th Amaldi meeting (which will be
published in Classical and Quantum Gravity
Deep learning based photoplethysmography classification for peripheral arterial disease detection: a proof-of-concept study
Optimal combination of signals from co-located gravitational wave interferometers for use in searches for a stochastic background
This article derives an optimal (i.e., unbiased, minimum variance) estimator
for the pseudo-detector strain for a pair of co-located gravitational wave
interferometers (such as the pair of LIGO interferometers at its Hanford
Observatory), allowing for possible instrumental correlations between the two
detectors. The technique is robust and does not involve any assumptions or
approximations regarding the relative strength of gravitational wave signals in
the detector pair with respect to other sources of correlated instrumental or
environmental noise. An expression is given for the effective power spectral
density of the combined noise in the pseudo-detector. This can then be
introduced into the standard optimal Wiener filter used to cross-correlate
detector data streams in order to obtain an optimal estimate of the stochastic
gravitational wave background. In addition, a dual to the optimal estimate of
strain is derived. This dual is constructed to contain no gravitational wave
signature and can thus be used as on "off-source" measurement to test
algorithms used in the "on-source" observation.Comment: 14 pages, 4 figures, submitted to Physical Review D Resubmitted after
editing paper in response to referee comments. Removed appendices A, B and
edited text accordingly. Improved legibility of figures. Corrected several
references. Corrected reference to science run number (S1 vs. S2) in text and
figure caption
Management to improve soil productivity and maximise lateral infiltration in permanent bed-furrow irrigation systems
The practice of conservation agriculture has been accepted for some time as conventional wisdom for improving soil conditions and raising the soil organic carbon levels of cropping land. This has been complemented over the past 10 years by controlled traffic agriculture, which has further improved soil management practices by almost eliminating compaction as a form of soil degradation.
Not withstanding the improved soil conditions that result from the practice of controlled traffic conservation agriculture, soils minimally tilled by such practices are still subject to consolidation through wetting and drying cycles. In this paper we report on a technique that further improves on these conservative soil management practices. This technique loosens soil at depth without any inversion,
and we examine the consequences this has on the proliferation and distribution of roots, the contents and
distributions of soil organic carbon and total soil nitrogen, the productivity of cropping soils and the lateral
infiltration of irrigation water in permanent bed-furrow systems. Results are drawn from experimental sites in Western Australia, Queensland and Pakistan
Clinical correlations with Porphyromonas gingivalis antibody responses in patients with early rheumatoid arthritis
Introduction: Prior studies have demonstrated an increased frequency of antibodies to Porphyromonas gingivalis (Pg), a leading agent of periodontal disease, in rheumatoid arthritis (RA) patients. However, these patients generally had long-standing disease, and clinical associations with these antibodies were inconsistent. Our goal was to examine Pg antibody responses and their clinical associations in patients with early RA prior to and after disease-modifying antirheumatic drug (DMARD) therapy. Methods: Serum samples from 50 DMARD-naĂŻve RA patients were tested using an enzyme-linked immunosorbent assay with whole-Pg sonicate. For comparison, serum samples were tested from patients with late RA, patients with other connective tissue diseases (CTDs), age-similar healthy hospital personnel and blood bank donors. Pg antibody responses in early RA patients were correlated with standard RA biomarkers, measures of disease activity and function. Results: At the time of enrollment, 17 (34%) of the 50 patients with early RA had positive immunoglobulin G (IgG) antibody responses to Pg, as did 13 (30%) of the 43 patients with late RA. RA patients had significantly higher Pg antibody responses than healthy hospital personnel and blood bank donors (P < 0.0001). Additionally, RA patients tended to have higher Pg antibody reactivity than patients with other CTDs (P = 0.1), and CTD patients tended to have higher Pg responses than healthy participants (P = 0.07). Compared with Pg antibody-negative patients, early RA patients with positive Pg responses more often had anti-cyclic citrullinated peptide (anti-CCP) antibody reactivity, their anti-CCP levels were significantly higher (P = 0.03) and the levels of anti-Pg antibodies correlated directly with anti-CCP levels (P < 0.01). Furthermore, at the time of study entry, the Pg-positive antibody group had greater rheumatoid factor values (P = 0.04) and higher inflammatory markers (erythrocyte sedimentation rate, or ESR) (P = 0.05), and they tended to have higher disease activity scores (Disease Activity Score based on 28-joint count (DAS28)-ESR and Clinical Disease Activity Index) and more functional impairment (Health Assessment Questionnaire). In Pg-positive patients, greater disease activity was still apparent after 12 months of DMARD therapy. Conclusions: A subset of early RA patients had positive Pg antibody responses. The responses correlated with anti-CCP antibody reactivity and to a lesser degree with ESR values. There was a trend toward greater disease activity in Pg-positive patients, and this trend remained after 12 months of DMARD therapy. These findings are consistent with a role for Pg in disease pathogenesis in a subset of RA patients
Resting metabolic rate and lung function in wild offshore common bottlenose dolphins, Tursiops truncatus, near Bermuda
© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Frontiers in Physiology 9 (2018): 886, doi:10.3389/fphys.2018.00886.Diving mammals have evolved a suite of physiological adaptations to manage respiratory gases during extended breath-hold dives. To test the hypothesis that offshore bottlenose dolphins have evolved physiological adaptations to improve their ability for extended deep dives and as protection for lung barotrauma, we investigated the lung function and respiratory physiology of four wild common bottlenose dolphins (Tursiops truncatus) near the island of Bermuda. We measured blood hematocrit (Hct, %), resting metabolic rate (RMR, l O2 ⋅ min-1), tidal volume (VT, l), respiratory frequency (fR, breaths ⋅ min-1), respiratory flow (l ⋅ min-1), and dynamic lung compliance (CL, l ⋅ cmH2O-1) in air and in water, and compared measurements with published results from coastal, shallow-diving dolphins. We found that offshore dolphins had greater Hct (56 ± 2%) compared to shallow-diving bottlenose dolphins (range: 30–49%), thus resulting in a greater O2 storage capacity and longer aerobic diving duration. Contrary to our hypothesis, the specific CL (sCL, 0.30 ± 0.12 cmH2O-1) was not different between populations. Neither the mass-specific RMR (3.0 ± 1.7 ml O2 ⋅ min-1 ⋅ kg-1) nor VT (23.0 ± 3.7 ml ⋅ kg-1) were different from coastal ecotype bottlenose dolphins, both in the wild and under managed care, suggesting that deep-diving dolphins do not have metabolic or respiratory adaptations that differ from the shallow-diving ecotypes. The lack of respiratory adaptations for deep diving further support the recently developed hypothesis that gas management in cetaceans is not entirely passive but governed by alteration in the ventilation-perfusion matching, which allows for selective gas exchange to protect against diving related problems such as decompression sickness.Funding for this project was provided by the Office of Naval Research (ONR YIP Award No. N000141410563, and Dolphin Quest, Inc. FHJ was supported by the Office of Naval Research (Award No. N00014-1410410) and an AIAS-COFUND fellowship from Aarhus Institute of Advanced Studies under the FP7 program of the EU (Agreement No. 609033)
Exclusion of enrolled participants in randomised controlled trials: what to do with ineligible participants?
OBJECTIVE: Post-randomisation exclusions in randomised controlled trials are common and may include participants identified as not meeting trial eligibility criteria after randomisation. We report how a decision might be reached and reported on, to include or exclude these participants. We illustrate using a motivating scenario from the BREATHE trial (Trial registration ClinicalTrials.gov, NCT02426112) evaluating azithromycin for the treatment of chronic lung disease in people aged 6-19 years with HIV in Zimbabwe and Malawi. KEY POINTS: Including all enrolled and randomised participants in the primary analysis of a trial ensures an unbiased estimate of the intervention effect using intention-to-treat principles, and minimises the effects of confounding through balanced allocation to trial arm. Ineligible participants are sometimes enrolled, due to measurement or human error. Of 347 participants enrolled into the BREATHE trial, 11 (3.2%) were subsequently found to be ineligible based on lung function criteria. We assumed no safety risk of azithromycin treatment; their inclusion in the trial and subsequent analysis of the intervention effect therefore mirrors clinical practice. Senior trial investigators considered diurnal variations in the measurement of lung function, advantages of retaining a higher sample size and advice from the Data Safety and Monitoring Board and Trial Steering Committee, and decided to include these participants in primary analysis. We planned and reported analyses including and excluding these participants, and in our case the interpretation of treatment effect was consistent. CONCLUSION: The decision, by senior investigators, on whether to exclude enrolled participants, should reflect issues of safety, treatment efficacy, statistical power and measurement error. As long as decisions are made prior to finalising the statistical analysis plan for the trial, the risk of exclusions creating bias should be minimal. The decision taken should be transparently reported and a sensitivity analysis can present the opposite decision
Initial operation of the International Gravitational Event Collaboration
The International Gravitational Event Collaboration, IGEC, is a coordinated
effort by research groups operating gravitational wave detectors working
towards the detection of millisecond bursts of gravitational waves. Here we
report on the current IGEC resonant bar observatory, its data analysis
procedures, the main properties of the first exchanged data set. Even though
the available data set is not complete, in the years 1997 and 1998 up to four
detectors were operating simultaneously. Preliminary results are mentioned.Comment: 8 pages, 2 figures, 3 tables; Proceeding of the GWDAW'99. Submitted
to the International Journal of Modern Physic
Avoiding Irrational NeuroLaw Exuberance: A Plea for Neuromodesty
In a 2002 editorial published in The Economist, the following warning was given: Genetics may yet threaten privacy, kill autonomy, make society homogeneous and gut the concept of human nature. But neuroscience could do all of these things first. The genome was fully sequenced in 2001, and there has not been one resulting major advance in therapeutic medicine since. Thus, even in its most natural applied domain-medicine-genetics has not had the far-reaching consequences that were envisioned. The same has been true for various other sciences that were predicted to revolutionize the law, including behavioral psychology, sociology, psychodynamic psychology, and others. This will also be true of neuroscience, which is simply the newest science on the block. Neuroscience is not going to do the terrible things The Economist fears, at least not for the foreseeable future. Neuroscience has many things to say but not nearly as much as people would hope, especially in relation to law. At most, in the near to intermediate term, neuroscience may make modest contributions to legal policy and case adjudication. Nonetheless, there has been irrational exuberance about the potential contribution of neuroscience, an issue I have addressed previously and referred to as Brain Overclaim Syndrome. I first consider the law\u27s motivation and the motivation of some advocates to turn to science to solve the very hard normative problems that law addresses. Part III discusses the law\u27s psychology and its concepts of the person and responsibility. The next Part considers the general relation of neuroscience to law, which I characterize as the issue of translation. Part V canvasses various distractions that have bedeviled clear thinking about the relation of scientific, causal accounts of behavior to responsibility. The following Part examines the limits of neurolaw and Part VII considers why neurolaw does not pose a genuinely radical challenge to the law\u27s concepts of the person and responsibility. Part VIII makes a case for cautious optimism about the contribution neuroscience may make to law in the near and intermediate term. A brief conclusion follows..
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