525 research outputs found
A framework for automated anomaly detection in high frequency water-quality data from in situ sensors
River water-quality monitoring is increasingly conducted using automated in
situ sensors, enabling timelier identification of unexpected values. However,
anomalies caused by technical issues confound these data, while the volume and
velocity of data prevent manual detection. We present a framework for automated
anomaly detection in high-frequency water-quality data from in situ sensors,
using turbidity, conductivity and river level data. After identifying end-user
needs and defining anomalies, we ranked their importance and selected suitable
detection methods. High priority anomalies included sudden isolated spikes and
level shifts, most of which were classified correctly by regression-based
methods such as autoregressive integrated moving average models. However, using
other water-quality variables as covariates reduced performance due to complex
relationships among variables. Classification of drift and periods of
anomalously low or high variability improved when we applied replaced anomalous
measurements with forecasts, but this inflated false positive rates.
Feature-based methods also performed well on high priority anomalies, but were
also less proficient at detecting lower priority anomalies, resulting in high
false negative rates. Unlike regression-based methods, all feature-based
methods produced low false positive rates, but did not and require training or
optimization. Rule-based methods successfully detected impossible values and
missing observations. Thus, we recommend using a combination of methods to
improve anomaly detection performance, whilst minimizing false detection rates.
Furthermore, our framework emphasizes the importance of communication between
end-users and analysts for optimal outcomes with respect to both detection
performance and end-user needs. Our framework is applicable to other types of
high frequency time-series data and anomaly detection applications
Assessing Psychological Well-Being: Self-Report Instruments for the NIH Toolbox
Objectiveâ
Psychological well-being (PWB) has a significant relationship with physical and
mental health. As part of the NIH Toolbox for the Assessment of Neurological and Behavioral
Function, we developed self-report item banks and short forms to assess PWB.
Study Design and Settingâ
Expert feedback and literature review informed the selection of
PWB concepts and the development of item pools for Positive Affect, Life Satisfaction, and
Meaning and Purpose. Items were tested with a community-dwelling U.S. internet panel sample of
adults aged 18 and above (N=552). Classical and item response theory (IRT) approaches were
used to evaluate unidimensionality, fit of items to the overall measure, and calibrations of those
items, including differential item function (DIF).
Resultsâ
IRT-calibrated item banks were produced for Positive Affect (34 items), Life
Satisfaction (16 items), and Meaning and Purpose (18 items). Their psychometric properties were
supported based on results of factor analysis, fit statistics, and DIF evaluation. All banks measured
the concepts precisely (reliability â„0.90) for more than 98% of participants.
Conclusionâ
These adult scales and item banks for PWB provide the flexibility, efficiency, and
precision necessary to promote future epidemiological, observational, and intervention research on
the relationship of PWB with physical and mental health
Optical Monitoring of the Broad-Line Radio Galaxy 3C390.3
We have undertaken a new ground-based monitoring campaign on the BLRG 3C390.3
to improve the measurement of the size of the BLR and to estimate the black
hole mass. Optical spectra and g-band images were observed in 2005 using the
2.4m telescope at MDM Observatory. Integrated emission-line flux variations
were measured for Ha, Hb, Hg, and for HeII4686, as well as g-band fluxes and
the optical AGN continuum at 5100A. The g-band fluxes and the AGN continuum
vary simultaneously within the uncertainties, tau=(0.2+-1.1)days. We find that
the emission-line variations are delayed with respect to the variable g-band
continuum by tau(Ha)=56.3(+2.4-6.6)days, tau(Hb)=44.3(+3.0_-3.3)days,
tau(Hg)=58.1(+4.3-6.1)days, and tau(HeII4686)=22.3(+6.5-3.8)days. The blue and
red peak in the double peaked line profiles, as well as the blue and red outer
profile wings, vary simultaneously within +-3 days. This provides strong
support for gravitationally bound orbital motion of the dominant part of the
line emitting gas. Combining the time delay of Ha and Hb and the separation of
the blue and red peak in the broad double-peaked profiles in their rms spectra,
we determine Mbh_vir=1.77(+0.29-0.31)x10^8Msol and using sigma_line of the rms
spectra Mbh_vir=2.60(+0.23-0.31)x10^8Msol for the central black hole of
3C390.3, respectively. Using the inclination angle of the line emitting region
the mass of the black hole amounts to Mbh=0.86(+0.19-0.18)x10^9 Msol
(peak-separation) and Mbh=1.26(+0.21-0.16)x10^9 Msol (sigma_line),
respectively. This result is consistent with the black hole masses indicated by
simple accretion disk models to describe the observed double-peaked profiles,
derived from the stellar dynamics of 3C390.3, and with the AGN
radius-luminosity relation. Thus, 3C390.3 as a radio-loud AGN with a low
Eddington ratio, Ledd/Lbol=0.02, follows the same AGN radius-luminosity
relation as radio-quiet AGN.Comment: accepted, scheduled for September 20, 2012, ApJ 75
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Oxidized phospholipids are proinflammatory and proatherogenic in hypercholesterolaemic mice.
Oxidized phospholipids (OxPL) are ubiquitous, are formed in many inflammatory tissues, including atherosclerotic lesions, and frequently mediate proinflammatory changes 1 . Because OxPL are mostly the products of non-enzymatic lipid peroxidation, mechanisms to specifically neutralize them are unavailable and their roles in vivo are largely unknown. We previously cloned the IgM natural antibody E06, which binds to the phosphocholine headgroup of OxPL, and blocks the uptake of oxidized low-density lipoprotein (OxLDL) by macrophages and inhibits the proinflammatory properties of OxPL2-4. Here, to determine the role of OxPL in vivo in the context of atherogenesis, we generated transgenic mice in the Ldlr-/- background that expressed a single-chain variable fragment of E06 (E06-scFv) using the Apoe promoter. E06-scFv was secreted into the plasma from the liver and macrophages, and achieved sufficient plasma levels to inhibit in vivo macrophage uptake of OxLDL and to prevent OxPL-induced inflammatory signalling. Compared to Ldlr-/- mice, Ldlr -/- E06-scFv mice had 57-28% less atherosclerosis after 4, 7 and even 12 months of 1% high-cholesterol diet. Echocardiographic and histologic evaluation of the aortic valves demonstrated that E06-scFv ameliorated the development of aortic valve gradients and decreased aortic valve calcification. Both cholesterol accumulation and in vivo uptake of OxLDL were decreased in peritoneal macrophages, and both peritoneal and aortic macrophages had a decreased inflammatory phenotype. Serum amyloid A was decreased by 32%, indicating decreased systemic inflammation, and hepatic steatosis and inflammation were also decreased. Finally, the E06-scFv prolonged life as measured over 15 months. Because the E06-scFv lacks the functional effects of an intact antibody other than the ability to bind OxPL and inhibit OxLDL uptake in macrophages, these data support a major proatherogenic role of OxLDL and demonstrate that OxPL are proinflammatory and proatherogenic, which E06 counteracts in vivo. These studies suggest that therapies inactivating OxPL may be beneficial for reducing generalized inflammation, including the progression of atherosclerosis, aortic stenosis and hepatic steatosis
On the variability of quasars: a link between Eddington ratio and optical variability?
Repeat scans by the Sloan Digital Sky Survey (SDSS) of a 278 square degree
stripe along the Celestial equator have yielded an average of over 10
observations each for nearly 8,000 spectroscopically confirmed quasars. Over
2500 of these quasars are in the redshift range such that the CIV emission line
is visible in the SDSS spectrum. Utilising the width of these CIV lines and the
luminosity of the nearby continuum, we estimate black hole masses for these
objects. In an effort to isolate the effects of black hole mass and luminosity
on the photometric variability of our dataset, we create several subsamples by
binning in these two physical parameters. By comparing the ensemble structure
functions of the quasars in these bins, we are able to reproduce the well-known
anticorrelation between luminosity and variability, now showing that this
anticorrelation is independent of the black hole mass. In addition, we find a
correlation between variability and the mass of the central black hole. By
combining these two relations, we identify the Eddington ratio as a possible
driver of quasar variability, most likely due to differences in accretion
efficiency.Comment: 13 pages, 5 figures, Accepted for publication in MNRA
Childhood cancer incidence and survival in Thailand: A comprehensive populationâbased registry analysis, 1990â2011
BackgroundSoutheast Asia is undergoing a transition from infectious to chronic diseases, including a dramatic increase in adult cancers. Childhood cancer research in Thailand has focused predominantly on leukemias and lymphomas or only examined children for a short period of time. This comprehensive multisite study examined childhood cancer incidence and survival rates in Thailand across all International Classification of Childhood Cancer (ICCC) groups over a 20âyear period.MethodsCancer cases diagnosed in children ages 0â19 years (n = 3574) from 1990 to 2011 were extracted from five provincial populationâbased Thai registries, covering approximately 10% of the population. Descriptive statistics of the quality of the registries were evaluated. Ageâstandardized incidence rates (ASRs) were calculated using the Segi world standard population, and relative survival was computed using the KaplanâMeier method. Changes in incidence and survival were analyzed using Joinpoint Regression and reported as annual percent changes (APC).ResultsThe ASR of all childhood cancers during the study period was 98.5 per million personâyears with 91.0 per million personâyears in 1990â2000 and 106.2 per million personâyears in 2001â2011. Incidence of all childhood cancers increased significantly (APC = 1.2%, P < 0.01). The top three cancer groups were leukemias, brain tumors, and lymphomas. The 5âyear survival for all childhood cancers significantly improved from 39.4% in 1990â2000 to 47.2% in 2001â2011 (P < 0.01).ConclusionsBoth childhood cancer incidence and survival rates have increased, suggesting improvement in the health care system as more cases are identified and treated. Analyzing childhood cancer trends in lowâ and middleâincome countries can improve understanding of cancer etiology and pediatric health care disparities.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146559/1/pbc27428_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146559/2/pbc27428.pd
Subjective and Objective Binge Eating in Relation to Eating Disorder Symptomatology, Depressive Symptoms, and Self-Esteem among Treatment-Seeking Adolescents with Bulimia Nervosa: Subjective and Objective Binge Eating
This study investigated the importance of the distinction between objective (OBE) and subjective binge eating (SBE) among 80 treatment-seeking adolescents with bulimia nervosa (BN). We explored relationships among OBEs, SBEs, eating disorder (ED) symptomatology, depression, and self-esteem using two approaches. Group comparisons showed that OBE and SBE groups did not differ on ED symptoms or self-esteem; however, the SBE group had significantly greater depression. Examining continuous variables, OBEs (not SBEs) accounted for significant unique variance in global ED pathology, vomiting, and self-esteem. SBEs (not OBEs) accounted for significant unique variance in restraint and depression. Both OBEs and SBEs accounted for significant unique variance in eating concern; neither accounted for unique variance in weight/shape concern, laxative use, diuretic use, or driven exercise. Loss of control, rather than amount of food, may be most important in defining binge eating. Additionally, OBEs may indicate broader ED pathology while SBEs may indicate restrictive/depressive symptomatology
Radiation-induced brachial plexopathy in patients with breast cancer treated with comprehensive adjuvant radiation therapy
Purpose: Our purpose was to describe the risk of radiation-induced brachial plexopathy (RIBP) in patients with breast cancer who received comprehensive adjuvant radiation therapy (RT).
Methods and Materials: Records for 498 patients who received comprehensive adjuvant RT (treatment of any residual breast tissue, the underlying chest wall, and regional nodes) between 2004 and 2012 were retrospectively reviewed. All patients were treated with conventional 3 to 5 field technique (CRT) until 2008, after which intensity modulated RT (IMRT) was introduced. RIBP events were determined by reviewing follow-up documentation from oncologic care providers. Patients with RIBP were matched (1:2) with a control group of patients who received CRT and a group of patients who received IMRT. Dosimetric analyses were performed in these patients to determine whether there were differences in ipsilateral brachial plexus dose distribution between RIBP and control groups.
Results: Median study follow-up was 88 months for the overall cohort and 92 months for the IMRT cohort. RIBP occurred in 4 CRT patients (1.6%) and 1 IMRT patient (0.4%) (
Conclusions: RIBP remains a rare complication of comprehensive adjuvant breast radiation and no clear dosimetric predictors for RIBP were identified in this study. The IMRT technique does not appear to adversely affect the development of this late toxicity
Non-pharmacological interventions to reduce psychological distress in patients undergoing diagnostic cardiac catheterization: a rapid review
Abstract
Background: Cardiac catheterization is the standard procedure for the diagnosis of coronary heart disease. The threat physically and emotionally from this procedure can effect the patientâs perception of their health. The heightened psychological distress associated with this diagnostic procedure can cause adverse patient outcomes. Non-pharmacologic interventions have been implemented to reduce psychological distress associated with cardiac catheterization.
Aims: The objective of this rapid review is to assess the efficacy of non-pharmacologic interventions (procedural education, relaxation techniques, psychological preparation) on psychological distress experienced by patients as they undergo a cardiac catheterization. Methods: Published, peer-reviewed, English-language intervention studies from 1981 to 2014 were identified in a search of CINAHL, Medline, and Cochrane Library. Eligible studies included adults undergoing cardiac catheterization. Studies included in this review used experimental and quasi-experimental designs and assessed at least one primary outcome: anxiety, depression, and pain to test non-pharmacologic interventions pre and post-cardiac catheterization. Researchers independently extracted data from included studies and completed a quality assessment using a published tool. Data was synthesised as a narrative.
Results: There were 29 eligible experimental and quasi-experimental studies that tested the 3 interventions (n=2504). Findings suggest that non-pharmacologic interventions were able to effectively reduce psychological distress in some patients undergoing cardiac catheterization.
Conclusion: Evidence is stronger in recent studies that non-pharmacologic interventions of procedural education and psychological preparation can reduce psychological distress in patients undergoing cardiac catheterization. Further research is needed to define the various relaxation techniques that can be effectively implemented for patients undergoing cardiac catheterization
RELICS: High-Resolution Constraints on the Inner Mass Distribution of the z=0.83 Merging Cluster RXJ0152.7-1357 from strong lensing
Strong gravitational lensing (SL) is a powerful means to map the distribution
of dark matter. In this work, we perform a SL analysis of the prominent X-ray
cluster RXJ0152.7-1357 (z=0.83, also known as CL 0152.7-1357) in \textit{Hubble
Space Telescope} images, taken in the framework of the Reionization Lensing
Cluster Survey (RELICS). On top of a previously known galaxy multiply
imaged by RXJ0152.7-1357, for which we identify an additional multiple image,
guided by a light-traces-mass approach we identify seven new sets of multiply
imaged background sources lensed by this cluster, spanning the redshift range
[1.79-3.93]. A total of 25 multiple images are seen over a small area of ~0.4
, allowing us to put relatively high-resolution constraints on the
inner matter distribution. Although modestly massive, the high degree of
substructure together with its very elongated shape make RXJ0152.7-1357 a very
efficient lens for its size. This cluster also comprises the third-largest
sample of z~6-7 candidates in the RELICS survey. Finally, we present a
comparison of our resulting mass distribution and magnification estimates with
those from a Lenstool model. These models are made publicly available through
the MAST archive.Comment: 15 Pages, 7 Figures, 4 Tables Accepted for publication in Ap
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