1,343 research outputs found
Cross-sectional associations of depressive symptom severity and functioning with health service use by older people in low-and-middle income countries
Background: Comprehensive understanding of the determinants of health service use (HSU) by older people with depression is essential for health service planning for an ageing global population. This study aimed to determine the extent to which depressive symptom severity and functioning are associated with HSU by older people with depression in low and middle income countries (LMICs). Methods: A cross-sectional analysis of the 10/66 Dementia Research Group population-based surveys dataset. Participants (n = 4590) were those aged 65 or older, in the clinical range for depressive symptoms (defined as scoring four or more on the EURO-D), living in 13 urban and/or rural catchment areas in nine LMICs. Associations were calculated using Poisson regression and random-effects meta-analysis. Results: After adjustment for confounding variables, (EURO-D) depressive symptom severity was significantly associated with “any community HSU” (Pooled Prevalence Ratios = 1.02; 95% CI = 1.01–1.03) but not hospital admission. Conversely, after adjustment, (WHODAS-II) functioning was significantly associated with hospital admission (Pooled PR = 1.14; 95% CI = 1.02–1.26) but not “any community HSU”. Conclusions: Depressive symptom severity does not explain a large proportion of the variance in HSU by older people with depression in LMICs. The association of functioning with this HSU is worthy of further investigation. In LMICs, variables related to accessibility may be more important correlates of HSU than variables directly related to health problems
Meta-analytic framework for efficiently identifying progression groups in highway condition analysis
The minimum message length two-dimensional segmenter (MML2DS) criterion is a powerful technique for road condition data analysis developed at the Nottingham Transportation Engineering Centre (NTEC), University of Nottingham. The criterion analyses condition data sets by simultaneously identifying optimum trends in condition progression, the position in time and space of maintenance interventions, longitudinal segments within links, and the error likelihood of each measurement. This is done in an unsupervised manner through classification and regression models on the basis of the minimum message length (MML) metric. Use of MML, however, often requires an exhaustive comparison of all possible models, which naturally raises considerable search-control issues. This is precisely the case with the MML2DS approach. This paper presents an efficient meta-analytic framework for controlling the generation of progression groups, which considerably reduces the search space before the application of MML2DS. This is achieved by identifying founder sets of longitudinal segments, around which families of segments are likely to be formed. An effective subset of these families is then selected, after which the MML2DS criterion is used as the final arbiter to determine ultimate model configurations and fits. This approach has proved to be very powerful, resulting in significant improvements in efficiency to the effect that accurate results are obtained in a few minutes where it previously took weeks with much smaller data sets. The indications are that this approach can be applied to other techniques besides MML2DS
The Zwicky Transient Facility: Surveys and Scheduler
We present a novel algorithm for scheduling the observations of time-domain
imaging surveys. Our Integer Linear Programming approach optimizes an observing
plan for an entire night by assigning targets to temporal blocks, enabling
strict control of the number of exposures obtained per field and minimizing
filter changes. A subsequent optimization step minimizes slew times between
each observation. Our optimization metric self-consistently weights
contributions from time-varying airmass, seeing, and sky brightness to maximize
the transient discovery rate. We describe the implementation of this algorithm
on the surveys of the Zwicky Transient Facility and present its on-sky
performance.Comment: Published in PASP Focus Issue on the Zwicky Transient Facility
(https://dx.doi.org/10.1088/1538-3873/ab0c2a). 13 Pages, 11 Figure
The Surgical Infection Society revised guidelines on the management of intra-abdominal infection
Background: Previous evidence-based guidelines on the management of intra-abdominal infection (IAI) were published by the Surgical Infection Society (SIS) in 1992, 2002, and 2010. At the time the most recent guideline was released, the plan was to update the guideline every five years to ensure the timeliness and appropriateness of the recommendations.
Methods: Based on the previous guidelines, the task force outlined a number of topics related to the treatment of patients with IAI and then developed key questions on these various topics. All questions were approached using general and specific literature searches, focusing on articles and other information published since 2008. These publications and additional materials published before 2008 were reviewed by the task force as a whole or by individual subgroups as to relevance to individual questions. Recommendations were developed by a process of iterative consensus, with all task force members voting to accept or reject each recommendation. Grading was based on the GRADE (Grades of Recommendation Assessment, Development, and Evaluation) system; the quality of the evidence was graded as high, moderate, or weak, and the strength of the recommendation was graded as strong or weak. Review of the document was performed by members of the SIS who were not on the task force. After responses were made to all critiques, the document was approved as an official guideline of the SIS by the Executive Council.
Results: This guideline summarizes the current recommendations developed by the task force on the treatment of patients who have IAI. Evidence-based recommendations have been made regarding risk assessment in individual patients; source control; the timing, selection, and duration of antimicrobial therapy; and suggested approaches to patients who fail initial therapy. Additional recommendations related to the treatment of pediatric patients with IAI have been included.
Summary: The current recommendations of the SIS regarding the treatment of patients with IAI are provided in this guideline
Long-term Periodicities of Cataclysmic Variables with Synoptic Surveys
A systematic study on the long-term periodicities of known Galactic
cataclysmic variables (CVs) was conducted. Among 1580 known CVs, 344 sources
were matched and extracted from the Palomar Transient Factory (PTF) data
repository. The PTF light curves were combined with the Catalina Real-Time
Transient Survey (CRTS) light curves and analyzed. Ten targets were found to
exhibit long-term periodic variability, which is not frequently observed in the
CV systems. These long-term variations are possibly caused by various
mechanisms, such as the precession of the accretion disk, hierarchical triple
star system, magnetic field change of the companion star, and other possible
mechanisms. We discuss the possible mechanisms in this study. If the long-term
period is less than several tens of days, the disk precession period scenario
is favored. However, the hierarchical triple star system or the variations in
magnetic field strengths are most likely the predominant mechanisms for longer
periods.Comment: 33 pages, 9 figures (manuscript form), Accepted for publication in
PAS
The Outbursts and Orbit of the Accreting Pulsar GS 1843-02=1845-024
We present observations of a series of 10 outbursts of pulsed hard X-ray flux from the transient 10.6 mHz accreting pulsar GS 1843-02, using the Burst and Transient Source Experiment on the Compton Gamma Ray Observatory. These outbursts occurred regularly every 242 days, coincident with the ephemeris of the periodic transient GRO J1849-03, which has recently been identified with the SAS 3 source 2S 1845-024. Our pulsed detection provides the first clear identification of GS 1843-02 with 2S 1845-024. We present a pulse timing analysis that shows that the 2S 1845-024 outbursts occur near the periastron passage of the neutron star's highly eccentric (e=0.88 ± 0.01) 242.18 ± 0.01 day period binary orbit about a high-mass (M_c>7 M_☉) companion. The orbit and transient outburst pattern strongly suggest that the pulsar is in a binary system with a Be star. Our observations show a long-term spin-up trend, with most of the spin-up occurring during the outbursts. From the measured spin-up rates and inferred luminosities we conclude that an accretion disk is present during the outbursts
Zwicky Transient Facility constraints on the optical emission from the nearby repeating FRB 180916.J0158+65
The discovery rate of fast radio bursts (FRBs) is increasing dramatically
thanks to new radio facilities. Meanwhile, wide-field instruments such as the
47 deg Zwicky Transient Facility (ZTF) survey the optical sky to study
transient and variable sources. We present serendipitous ZTF observations of
the CHIME repeating source FRB 180916.J0158+65, that was localized to a spiral
galaxy 149 Mpc away and is the first FRB suggesting periodic modulation in its
activity. While 147 ZTF exposures corresponded to expected high-activity
periods of this FRB, no single ZTF exposure was at the same time as a CHIME
detection. No optical source was found at the FRB location in 683
ZTF exposures, totalling 5.69 hours of integration time. We combined ZTF upper
limits and expected repetitions from FRB 180916.J0158+65 in a statistical
framework using a Weibull distribution, agnostic of periodic modulation priors.
The analysis yielded a constraint on the ratio between the optical and radio
fluences of , corresponding to an optical energy erg for a fiducial 10 Jy ms FRB (90%
confidence). A deeper (but less statistically robust) constraint of can be placed assuming a rate of Jy ms)= hr and
FRB occurring during exposures taken in high-activity windows. The
constraint can be improved with shorter per-image exposures and longer
integration time, or observing FRBs at higher Galactic latitudes. This work
demonstrated how current surveys can statistically constrain multi-wavelength
counterparts to FRBs even without deliberately scheduled simultaneous radio
observation.Comment: Accepted for publication in ApJL, 9 pages, 4 figures, 1 tabl
The Outbursts and Orbit of the Accreting Pulsar GS 1843-02 = 2S 1845-024
We present observations of a series of 10 outbursts of pulsed hard X-ray flux
from the transient 10.6 mHz accreting pulsar GS 1843-02, using the Burst and
Transient Source Experiment on the Compton Gamma Ray Observatory. These
outbursts occurred regularly every 242 days, coincident with the ephemeris of
the periodic transient GRO J1849-03 (Zhang et al. 1996), which has recently
been identified with the SAS 3 source 2S 1845-024 (Soffitta et al. 1998). Our
pulsed detection provides the first clear identification of GS 1843-02 with 2S
1845-024. We present a pulse timing analysis which shows that the 2S 1845-024
outbursts occur near the periastron passage of the neutron star's highly
eccentric (e = 0.88+-0.01) 242.18+-0.01 day period binary orbit about a high
mass (M > 7 solar masses) companion. The orbit and transient outburst pattern
strongly suggest the pulsar is in a binary system with a Be star. Our
observations show a long-term spin-up trend, with most of the spin-up occurring
during the outbursts. From the measured spin-up rates and inferred luminosities
we conclude that an accretion disk is present during the outbursts.Comment: Accepted for publication in Astrophysical Journa
Self-rated health and its association with mortality in older adults in China, India and Latin America—a 10/66 Dementia Research Group study
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