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Diagnostic criteria for major depressive disorder allow for heterogeneous symptom profiles but genetic analysis of major depressive symptoms has the potential to identify clinical and etiological subtypes. There are several challenges to integrating symptom data from genetically informative cohorts, such as sample size differences between clinical and community cohorts and various patterns of missing data.
Methods
We conducted genome-wide association studies of major depressive symptoms in three cohorts that were enriched for participants with a diagnosis of depression (Psychiatric Genomics Consortium, Australian Genetics of Depression Study, Generation Scotland) and three community cohorts who were not recruited on the basis of diagnosis (Avon Longitudinal Study of Parents and Children, Estonian Biobank, and UK Biobank). We fit a series of confirmatory factor models with factors that accounted for how symptom data was sampled and then compared alternative models with different symptom factors.
Results
The best fitting model had a distinct factor for Appetite/Weight symptoms and an additional measurement factor that accounted for the skip-structure in community cohorts (use of Depression and Anhedonia as gating symptoms).
Conclusion
The results show the importance of assessing the directionality of symptoms (such as hypersomnia versus insomnia) and of accounting for study and measurement design when meta-analyzing genetic association data.
Although the link between alcohol involvement and behavioral phenotypes (e.g. impulsivity, negative affect, executive function [EF]) is well-established, the directionality of these associations, specificity to stages of alcohol involvement, and extent of shared genetic liability remain unclear. We estimate longitudinal associations between transitions among alcohol milestones, behavioral phenotypes, and indices of genetic risk.
Methods
Data came from the Collaborative Study on the Genetics of Alcoholism (n = 3681; ages 11–36). Alcohol transitions (first: drink, intoxication, alcohol use disorder [AUD] symptom, AUD diagnosis), internalizing, and externalizing phenotypes came from the Semi-Structured Assessment for the Genetics of Alcoholism. EF was measured with the Tower of London and Visual Span Tasks. Polygenic scores (PGS) were computed for alcohol-related and behavioral phenotypes. Cox models estimated associations among PGS, behavior, and alcohol milestones.
Results
Externalizing phenotypes (e.g. conduct disorder symptoms) were associated with future initiation and drinking problems (hazard ratio (HR)⩾1.16). Internalizing (e.g. social anxiety) was associated with hazards for progression from first drink to severe AUD (HR⩾1.55). Initiation and AUD were associated with increased hazards for later depressive symptoms and suicidal ideation (HR⩾1.38), and initiation was associated with increased hazards for future conduct symptoms (HR = 1.60). EF was not associated with alcohol transitions. Drinks per week PGS was linked with increased hazards for alcohol transitions (HR⩾1.06). Problematic alcohol use PGS increased hazards for suicidal ideation (HR = 1.20).
Conclusions
Behavioral markers of addiction vulnerability precede and follow alcohol transitions, highlighting dynamic, bidirectional relationships between behavior and emerging addiction.
When sheep are transported they are potentially exposed to a number of factors, including water and feed deprivation, low space allowance and elevated environmental temperature, that are not related to vehicle motion but could result in animal welfare problems, either on their own or in combination. In a 2x2 factorial experiment, groups of sheep (n = 6) were moved from individual pens where they had access to hay and water to environmental chambers kept at either 14°C or 21°C. Within each chamber, half the sheep had access to water but they were all kept at a space allowance of 041m2 sheep−1 without feed. After 24h they were returned to their individual pens and offered hay and water. Behaviour and a range of biochemical measurements of dehydration and feed restriction were recorded before, during and after the treatment period. During the treatment period there was no evidence of dehydration, and sheep with access to water drank less than they did before the treatment. The plasma concentration of free fatty acids increased during fasting and, post-treatment, the intake of hay was greater than before treatment. The rapid post-treatment intake of dry feed was associated with some evidence of dehydration, as indicated by increased plasma osmolality and plasma vasopressin concentration. This suggests that following provision and consumption of large quantities of feed after a period without access to feed and water during transportation, sheep must be allowed sufficient time to drink before a subsequent journey is undertaken.
This paper proposes a novel origami-inspired adult diaper design that improves discretion by reducing sag and increasing wicking across the entire diaper pad. While other diapers rely on supporting elastics to reduce the sag of the diaper as a whole, this paper proposes an absorbent core that uses liquid activated shaping to take a specified shape. Origami-based folds are also incorporated into the diaper design to increase wicking performance. The paper introduces a disposable compliant mechanism waistband used to deploy the diaper, making it easier to put onto one’s body.
The GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) is a radio continuum survey at 76–227 MHz of the entire southern sky (Declination
$<\!{+}30^{\circ}$
) with an angular resolution of
${\approx}2$
arcmin. In this paper, we combine GLEAM data with optical spectroscopy from the 6dF Galaxy Survey to construct a sample of 1 590 local (median
$z \approx 0.064$
) radio sources with
$S_{200\,\mathrm{MHz}} > 55$
mJy across an area of
${\approx}16\,700\,\mathrm{deg}^{2}$
. From the optical spectra, we identify the dominant physical process responsible for the radio emission from each galaxy: 73% are fuelled by an active galactic nucleus (AGN) and 27% by star formation. We present the local radio luminosity function for AGN and star-forming (SF) galaxies at 200 MHz and characterise the typical radio spectra of these two populations between 76 MHz and
${\sim}1$
GHz. For the AGN, the median spectral index between 200 MHz and
${\sim}1$
GHz,
$\alpha_{\mathrm{high}}$
, is
$-0.600 \pm 0.010$
(where
$S \propto \nu^{\alpha}$
) and the median spectral index within the GLEAM band,
$\alpha_{\mathrm{low}}$
, is
$-0.704 \pm 0.011$
. For the SF galaxies, the median value of
$\alpha_{\mathrm{high}}$
is
$-0.650 \pm 0.010$
and the median value of
$\alpha_{\mathrm{low}}$
is
$-0.596 \pm 0.015$
. Among the AGN population, flat-spectrum sources are more common at lower radio luminosity, suggesting the existence of a significant population of weak radio AGN that remain core-dominated even at low frequencies. However, around 4% of local radio AGN have ultra-steep radio spectra at low frequencies (
$\alpha_{\mathrm{low}} < -1.2$
). These ultra-steep-spectrum sources span a wide range in radio luminosity, and further work is needed to clarify their nature.
In this paper, we describe the system design and capabilities of the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope at the conclusion of its construction project and commencement of science operations. ASKAP is one of the first radio telescopes to deploy phased array feed (PAF) technology on a large scale, giving it an instantaneous field of view that covers $31\,\textrm{deg}^{2}$ at $800\,\textrm{MHz}$. As a two-dimensional array of 36$\times$12 m antennas, with baselines ranging from 22 m to 6 km, ASKAP also has excellent snapshot imaging capability and 10 arcsec resolution. This, combined with 288 MHz of instantaneous bandwidth and a unique third axis of rotation on each antenna, gives ASKAP the capability to create high dynamic range images of large sky areas very quickly. It is an excellent telescope for surveys between 700 and $1800\,\textrm{MHz}$ and is expected to facilitate great advances in our understanding of galaxy formation, cosmology, and radio transients while opening new parameter space for discovery of the unknown.
The Rapid ASKAP Continuum Survey (RACS) is the first large-area survey to be conducted with the full 36-antenna Australian Square Kilometre Array Pathfinder (ASKAP) telescope. RACS will provide a shallow model of the ASKAP sky that will aid the calibration of future deep ASKAP surveys. RACS will cover the whole sky visible from the ASKAP site in Western Australia and will cover the full ASKAP band of 700–1800 MHz. The RACS images are generally deeper than the existing NRAO VLA Sky Survey and Sydney University Molonglo Sky Survey radio surveys and have better spatial resolution. All RACS survey products will be public, including radio images (with
$\sim$
15 arcsec resolution) and catalogues of about three million source components with spectral index and polarisation information. In this paper, we present a description of the RACS survey and the first data release of 903 images covering the sky south of declination
$+41^\circ$
made over a 288-MHz band centred at 887.5 MHz.
Coronavirus disease 2019 (COVID-19) has migrated to regions that were initially spared, and it is likely that different populations are currently at risk for illness. Herein, we present our observations of the change in characteristics and resource use of COVID-19 patients over time in a national system of community hospitals to help inform those managing surge planning, operational management, and future policy decisions.
To determine risk factors for mortality among COVID-19 patients admitted to a system of community hospitals in the United States.
Design:
Retrospective analysis of patient data collected from the routine care of COVID-19 patients.
Setting:
System of >180 acute-care facilities in the United States.
Participants:
All admitted patients with positive identification of COVID-19 and a documented discharge as of May 12, 2020.
Methods:
Determination of demographic characteristics, vital signs at admission, patient comorbidities and recorded discharge disposition in this population to construct a logistic regression estimating the odds of mortality, particular for those patients characterized as not being critically ill at admission.
Results:
In total, 6,180 COVID-19+ patients were identified as of May 12, 2020. Most COVID-19+ patients (4,808, 77.8%) were admitted directly to a medical-surgical unit with no documented critical care or mechanical ventilation within 8 hours of admission. After adjusting for demographic characteristics, comorbidities, and vital signs at admission in this subgroup, the largest driver of the odds of mortality was patient age (OR, 1.07; 95% CI, 1.06–1.08; P < .001). Decreased oxygen saturation at admission was associated with increased odds of mortality (OR, 1.09; 95% CI, 1.06–1.12; P < .001) as was diabetes (OR, 1.57; 95% CI, 1.21–2.03; P < .001).
Conclusions:
The identification of factors observable at admission that are associated with mortality in COVID-19 patients who are initially admitted to non-critical care units may help care providers, hospital epidemiologists, and hospital safety experts better plan for the care of these patients.
The use of three-dimensional printing has been rapidly expanding over the last several decades. Virtual surgical three-dimensional simulation and planning has been shown to increase efficiency and accuracy in various clinical scenarios.
Objectives
To report the feasibility of three-dimensional printing in paediatric laryngotracheal stenosis and discuss potential applications of three-dimensional printed models in airway surgery.
Method
Retrospective case series in a tertiary care aerodigestive centre.
Results
Three-dimensional printing was undertaken in two cases of paediatric laryngotracheal stenosis. One patient with grade 4 subglottic stenosis with posterior glottic involvement underwent an extended partial cricotracheal reconstruction. Another patient with grade 4 tracheal stenosis underwent tracheal resection and end-to-end anastomosis. Models of both tracheas were printed using PolyJet technology from a Stratasys Connex2 printer.
Conclusion
It is feasible to demonstrate stenosis in three-dimensional printed models, allowing for patient-specific pre-operative surgical simulation. The models serve as an educational tool for patients’ understanding of the surgery, and for teaching residents and fellows.
We present a workflow to track icebergs in proglacial fjords using oblique time-lapse photos and the Lucas-Kanade optical flow algorithm. We employ the workflow at LeConte Bay, Alaska, where we ran five time-lapse cameras between April 2016 and September 2017, capturing more than 400 000 photos at frame rates of 0.5–4.0 min−1. Hourly to daily average velocity fields in map coordinates illustrate dynamic currents in the bay, with dominant downfjord velocities (exceeding 0.5 m s−1 intermittently) and several eddies. Comparisons with simultaneous Acoustic Doppler Current Profiler (ADCP) measurements yield best agreement for the uppermost ADCP levels (~ 12 m and above), in line with prevalent small icebergs that trace near-surface currents. Tracking results from multiple cameras compare favorably, although cameras with lower frame rates (0.5 min−1) tend to underestimate high flow speeds. Tests to determine requisite temporal and spatial image resolution confirm the importance of high image frame rates, while spatial resolution is of secondary importance. Application of our procedure to other fjords will be successful if iceberg concentrations are high enough and if the camera frame rates are sufficiently rapid (at least 1 min−1 for conditions similar to LeConte Bay).
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
To determine which healthcare worker (HCW) roles and patient care activities are associated with acquisition of vancomycin-resistant Enterococcus (VRE) on HCW gloves or gowns after patient care, as a surrogate for transmission to other patients.
Design
Prospective cohort study.
Setting
Medical and surgical intensive care units at a tertiary-care academic institution.
Participants
VRE-colonized patients on Contact Precautions and their HCWs.
Methods
Overall, 94 VRE-colonized patients and 469 HCW–patient interactions were observed. Research staff recorded patient care activities and cultured HCW gloves and gowns for VRE before doffing and exiting patient room.
Results
VRE were isolated from 71 of 469 HCWs’ gloves or gowns (15%) following patient care. Occupational/physical therapists, patient care technicians, nurses, and physicians were more likely than environmental services workers and other HCWs to have contaminated gloves or gowns. Compared to touching the environment alone, the odds ratio (OR) for VRE contamination associated with touching both the patient (or objects in the immediate vicinity of the patient) and environment was 2.78 (95% confidence interval [CI], 0.99–0.77) and the OR associated with touching only the patient (or objects in the immediate vicinity) was 3.65 (95% CI, 1.17–11.41). Independent risk factors for transmission of VRE to HCWs were touching the patient’s skin (OR, 2.18; 95% CI, 1.15–4.13) and transferring the patient into or out of bed (OR, 2.66; 95% CI, 1.15–6.43).
Conclusion
Patient contact is a major risk factor for HCW contamination and subsequent transmission. Interventions should prioritize contact precautions and hand hygiene for HCWs whose activities involve touching the patient.
Extinction is the complete loss of a species, but the accuracy of that status depends on the overall information about the species. Dracaena umbraculifera was described in 1797 from a cultivated plant attributed to Mauritius, but repeated surveys failed to relocate it and it was categorized as Extinct on the IUCN Red List. However, several individuals labelled as D. umbraculifera grow in botanical gardens, suggesting that the species’ IUCN status may be inaccurate. The goal of this study was to understand (1) where D. umbraculifera originated, (2) which species are its close relatives, (3) whether it is extinct, and (4) the identity of the botanical garden accessions and whether they have conservation value. We sequenced a cpDNA region of Dracaena from Mauritius, botanical garden accessions labelled as D. umbraculifera, and individuals confirmed to be D. umbraculifera based on morphology, one of which is a living plant in a private garden. We included GenBank accessions of Dracaena from Madagascar and other locations and reconstructed the phylogeny using Bayesian and parsimony approaches. Phylogenies indicated that D. umbraculifera is more closely related to Dracaena reflexa from Madagascar than to Mauritian Dracaena. As anecdotal information indicated that the living D. umbraculifera originated from Madagascar, we conducted field expeditions there and located five wild populations; the species’ IUCN status should therefore be Critically Endangered because < 50 wild individuals remain. Although the identity of many botanical garden samples remains unresolved, this study highlights the importance of living collections for facilitating new discoveries and the importance of documenting and conserving the flora of Madagascar.
Thermal resistance across the interface between touching surfaces is critical for many industrial applications. We developed a network model to predict the macroscopic thermal resistance of mechanically contacting surfaces. Contacting interfaces are fractally rough, with small islands of locally intimate contact separated by regions with a wider gas filled boundary gap. Heat flow across the interface is therefore heterogeneous and thus the contact model is based on a network of thermal resistors representing boundary resistance at local contacts and the access resistance for lateral transport to contacts. Molecular dynamics simulations have been performed to characterize boundary resistance of Silicon Alumina interfaces for testing the sensitivity of thermal resistance to contact opening. Boltzmann transport simulations of access resistance in Si are conducted in the ballistic transport regime.
The implementation of a successful glyphosate resistance management strategy
requires a simple and cost-effective method for detecting resistance in key
weeds. To date, however, glyphosate resistance is still routinely confirmed
via laborious and time consuming whole-plant pot assays using seeds
collected at the end of the growing season. Here, we describe a simple,
early-season bioassay for detecting evolved glyphosate resistance in grass
and broadleaf weeds. It involves transplanting suspected glyphosate
resistant seedlings alongside known sensitive and resistant standards into
agar containing informative rates of herbicide and recording percentage
survival 14 d after plating. The method was validated using sensitive and
resistant populations of Lolium, Eleusine,
Conyza, and Amaranthus species
encompassing the main glyphosate resistance mechanisms, namely, impaired
translocation, EPSPS gene duplication, and mutations. The whole plant pot
and agar-based seedling tests generated comparable resistance indices in
dose-response assays and percentage survival at discriminating glyphosate
rates. The method was applied successfully to detect resistance in a rigid
ryegrass population collected from a French vineyard well before glyphosate
was applied in the field for the current season. Additionally, the test was
shown to be highly transferable to several other grass and broadleaf weeds
that have evolved resistance to glyphosate. One major attribute of the
method is that it is capable of detecting resistance regardless of the
mechanism involved. In addition to being very simple, quick and,
cost-effective, it allows determination of glyphosate resistance in weeds
prior to field application. It thus offers the opportunity for an informed
choice of herbicides for effective weed control.
In this project we have involved four high-achieving pre-university summer placement students in the development of undergraduate teaching materials, namely tutorial videos for first year undergraduate Electrical and Electronic Engineering lab, and computer simulations of didactic semiconductor structures for an Electrical Science first year compulsory taught module. Here we describe our approach and preliminary results.
To examine self-reported practices and policies to reduce infection and transmission of multidrug-resistant organisms (MDRO) in healthcare settings outside the United States.
DESIGN
Cross-sectional survey.
PARTICIPANTS
International members of the Society for Healthcare Epidemiology of America (SHEA) Research Network.
METHODS
Electronic survey of infection control and prevention practices, capabilities, and barriers outside the United States and Canada. Participants were stratified according to their country’s economic development status as defined by the World Bank as low-income, lower-middle-income, upper-middle-income, and high-income.
RESULTS
A total of 76 respondents (33%) of 229 SHEA members outside the United States and Canada completed the survey questionnaire, representing 30 countries. Forty (53%) were high-, 33 (43%) were middle-, and 1 (1%) was a low-income country. Country data were missing for 2 respondents (3%). Of the 76 respondents, 64 (84%) reported having a formal or informal antibiotic stewardship program at their institution. High-income countries were more likely than middle-income countries to have existing MDRO policies (39/64 [61%] vs 25/64 [39%], P=.003) and to place patients with MDRO in contact precautions (40/72 [56%] vs 31/72 [44%], P=.05). Major barriers to preventing MDRO transmission included constrained resources (infrastructure, supplies, and trained staff) and challenges in changing provider behavior.
CONCLUSIONS
In this survey, a substantial proportion of institutions reported encountering barriers to implementing key MDRO prevention strategies. Interventions to address capacity building internationally are urgently needed. Data on the infection prevention practices of low income countries are needed.
We describe the performance of the Boolardy Engineering Test Array, the prototype for the Australian Square Kilometre Array Pathfinder telescope. Boolardy Engineering Test Array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarisation beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of Boolardy Engineering Test Array’s performance: sensitivity, beam characteristics, polarimetric properties, and image quality. We summarise the astronomical science that it has produced and draw lessons from operating Boolardy Engineering Test Array that will be relevant to the commissioning and operation of the final Australian Square Kilometre Array Path telescope.