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The impact of chronic pain and opioid use on cognitive decline and mild cognitive impairment (MCI) is unclear. We investigated these associations in early older adulthood, considering different definitions of chronic pain.
Methods:
Men in the Vietnam Era Twin Study of Aging (VETSA; n = 1,042) underwent cognitive testing and medical history interviews at average ages 56, 62, and 68. Chronic pain was defined using pain intensity and interference ratings from the SF-36 over 2 or 3 waves (categorized as mild versus moderate-to-severe). Opioid use was determined by self-reported medication use. Amnestic and non-amnestic MCI were assessed using the Jak-Bondi approach. Mixed models and Cox proportional hazards models were used to assess associations of pain and opioid use with cognitive decline and risk for MCI.
Results:
Moderate-to-severe, but not mild, chronic pain intensity (β = −.10) and interference (β = −.23) were associated with greater declines in executive function. Moderate-to-severe chronic pain intensity (HR = 1.75) and interference (HR = 3.31) were associated with a higher risk of non-amnestic MCI. Opioid use was associated with a faster decline in verbal fluency (β = −.18) and a higher risk of amnestic MCI (HR = 1.99). There were no significant interactions between chronic pain and opioid use on cognitive decline or MCI risk (all p-values > .05).
Discussion:
Moderate-to-severe chronic pain intensity and interference related to executive function decline and greater risk of non-amnestic MCI; while opioid use related to verbal fluency decline and greater risk of amnestic MCI. Lowering chronic pain severity while reducing opioid exposure may help clinicians mitigate later cognitive decline and dementia risk.
We present the first results from a new backend on the Australian Square Kilometre Array Pathfinder, the Commensal Realtime ASKAP Fast Transient COherent (CRACO) upgrade. CRACO records millisecond time resolution visibility data, and searches for dispersed fast transient signals including fast radio bursts (FRB), pulsars, and ultra-long period objects (ULPO). With the visibility data, CRACO can localise the transient events to arcsecond-level precision after the detection. Here, we describe the CRACO system and report the result from a sky survey carried out by CRACO at 110-ms resolution during its commissioning phase. During the survey, CRACO detected two FRBs (including one discovered solely with CRACO, FRB 20231027A), reported more precise localisations for four pulsars, discovered two new RRATs, and detected one known ULPO, GPM J1839 $-$10, through its sub-pulse structure. We present a sensitivity calibration of CRACO, finding that it achieves the expected sensitivity of 11.6 Jy ms to bursts of 110 ms duration or less. CRACO is currently running at a 13.8 ms time resolution and aims at a 1.7 ms time resolution before the end of 2024. The planned CRACO has an expected sensitivity of 1.5 Jy ms to bursts of 1.7 ms duration or less and can detect $10\times$ more FRBs than the current CRAFT incoherent sum system (i.e. 0.5 $-$2 localised FRBs per day), enabling us to better constrain the models for FRBs and use them as cosmological probes.
We present WALLABY pilot data release 1, the first public release of H i pilot survey data from the Wide-field ASKAP L-band Legacy All-sky Blind Survey (WALLABY) on the Australian Square Kilometre Array Pathfinder. Phase 1 of the WALLABY pilot survey targeted three $60\,\mathrm{deg}^{2}$ regions on the sky in the direction of the Hydra and Norma galaxy clusters and the NGC 4636 galaxy group, covering the redshift range of $z \lesssim 0.08$. The source catalogue, images and spectra of nearly 600 extragalactic H i detections and kinematic models for 109 spatially resolved galaxies are available. As the pilot survey targeted regions containing nearby group and cluster environments, the median redshift of the sample of $z \approx 0.014$ is relatively low compared to the full WALLABY survey. The median galaxy H i mass is $2.3 \times 10^{9}\,{\rm M}_{{\odot}}$. The target noise level of $1.6\,\mathrm{mJy}$ per 30′′ beam and $18.5\,\mathrm{kHz}$ channel translates into a $5 \sigma$ H i mass sensitivity for point sources of about $5.2 \times 10^{8} \, (D_{\rm L} / \mathrm{100\,Mpc})^{2} \, {\rm M}_{{\odot}}$ across 50 spectral channels (${\approx} 200\,\mathrm{km \, s}^{-1}$) and a $5 \sigma$ H i column density sensitivity of about $8.6 \times 10^{19} \, (1 + z)^{4}\,\mathrm{cm}^{-2}$ across 5 channels (${\approx} 20\,\mathrm{km \, s}^{-1}$) for emission filling the 30′′ beam. As expected for a pilot survey, several technical issues and artefacts are still affecting the data quality. Most notably, there are systematic flux errors of up to several 10% caused by uncertainties about the exact size and shape of each of the primary beams as well as the presence of sidelobes due to the finite deconvolution threshold. In addition, artefacts such as residual continuum emission and bandpass ripples have affected some of the data. The pilot survey has been highly successful in uncovering such technical problems, most of which are expected to be addressed and rectified before the start of the full WALLABY survey.
The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to $\sim\!5$ yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of $\sim\!162$ h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of $0.24\ \mathrm{mJy\ beam}^{-1}$ and angular resolution of $12-20$ arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.
Five international consensus statements on concussion in sports have been published. This commentary argues that there is a strong need for a new approach to them that foregrounds public health expertise and patient-centered guidance. Doing so will help players, parents and practitioners keep perspective about these potentially life-altering injuries especially when they recur.
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.
Mental health and wellbeing, including addressing impacts of historical trauma and substance use among young people, has been identified as a key priority by Indigenous communities and leaders across Canada and globally. Yet, research to understand mental health among young Indigenous people who have used drugs is limited.
Aims.
To examine longitudinal risk and strengths-based factors associated with psychological distress among young Indigenous people who use drugs.
Method.
The Cedar Project is an ongoing cohort study involving young Indigenous people who use drugs in Vancouver, Prince George, and Chase, British Columbia, Canada. This study included participants who completed the Symptom Checklist-90-Revised, returned for follow-up between 2010 and 2012, and completed the Childhood Trauma Questionnaire. Adjusted linear mixed-effects models estimated effects of study variables on changes in area T-scores of psychological distress.
Results.
Of 202 eligible participants, 53% were women and the mean age was 28 years. Among men, childhood maltreatment (emotional abuse, physical abuse, sexual abuse, physical neglect), any drug use, blackouts from drinking, and sex work were associated with increased distress. Among women, childhood maltreatment (emotional abuse, physical abuse, physical neglect), blackouts from drinking, and sexual assault were associated with increased distress, while having attempted to quit using drugs was associated with reduced distress. Marginal associations were observed between speaking their traditional language and living by traditional culture with lower distress among men.
Conclusion.
Culturally safe mental wellness interventions are urgently needed to address childhood trauma and harmful coping strategies that exacerbate distress among young Indigenous people who use drugs.
Discrepancies between clay mineral and organic indicators of very low-grade metamorphism have been observed from the Southern Uplands of Scotland. In the Southern Belt, I-S expandability ranges from 18–5% and chitinozoan reflectance from 0·8–2·1% R0 mean; a clear correlation exists between I-S expandability and organic maturity. At Dob's Linn in the Central Belt, I-S expandabilities range from 18–10%, and chitinozoan reflectance from 3·6–4·8% R0 mean. The results from Dob's Linn show anomalously high I-S expandabilities with respect to maturity, both in comparison with the Southern Belt and with previous work from other regions. K-feldspar is present in variable amounts in the Southern Belt, but is not detectable by XRD at Dob's Linn. Low K+ activity is believed to have resulted in a slower reaction rate at Dob's Linn, and a consequent “lag” in I-S expandability with respect to the Southern Belt.
A crops ability to both suppress weed growth and tolerate weed competition is a key consideration when taking an agroecological approach to weed management. Amongst other cereals, oats are widely considered to have superior weed competitiveness yet studies examining competitive ability of oat varieties are rare. We investigated the ability of oats to suppress weeds and yield in the presence of competition from weeds in trials involving five husked and three naked oat varieties at an organic site in the east of England over four trial years (2009-13). We identified a number of key traits that were important for weed suppression including establishment rate, tillering ability, and early leaf area index (LAI) which highlight the importance of rapid early growth rate. Furthermore, taller varieties tended to be more weed tolerant but not necessarily more suppressive. Trade-offs between competitive traits and yield were not found in this study. Crop tillering ability was highlighted as an important trait for selection due to its beneficial effects on weed suppression as well as grain yield and also its high heritability.
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.
This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
Heat stress (HS) jeopardizes livestock health and productivity and both may in part be mediated by reduced intestinal integrity. Dietary zinc improves a variety of bowel diseases, which are characterized by increased intestinal permeability. Study objectives were to evaluate the effects of supplemental zinc amino acid complex (ZnAA) on intestinal integrity in heat-stressed growing pigs. Crossbred gilts (43±6 kg BW) were ad libitum fed one of three diets: (1) control (ZnC; 120 ppm Zn as ZnSO4; n=13), (2) control+100 ppm Zn as ZnAA (Zn220; containing a total of 220 ppm Zn; n=14), and (3) control+200 ppm Zn as ZnAA (Zn320; containing a total of 320 ppm Zn; n=16). After 25 days on their respective diets, all pigs were exposed to constant HS conditions (36°C, ∼50% humidity) for either 1 or 7 days. At the end of the environmental exposure, pigs were euthanized and blood and intestinal tissues were harvested immediately after sacrifice. As expected, HS increased rectal temperature (P⩽0.01; 40.23°C v. 38.93°C) and respiratory rate (P⩽0.01; 113 v. 36 bpm). Pigs receiving ZnAA tended to have increased rectal temperature (P=0.07; +0.27°C) compared with ZnC-fed pigs. HS markedly reduced feed intake (FI; P⩽0.01; 59%) and caused BW loss (2.10 kg), but neither variable was affected by dietary treatment. Fresh intestinal segments were assessed ex vivo for intestinal integrity. As HS progressed from days 1 to 7, both ileal and colonic transepithelial electrical resistance (TER) decreased (P⩽0.05; 34% and 22%, respectively). This was mirrored by an increase in ileal and colonic permeability to the macromolecule dextran (P⩽0.01; 13- and 56-fold, respectively), and increased colonic lipopolysaccharide permeability (P⩽0.05; threefold) with time. There was a quadratic response (P⩽0.05) to increasing ZnAA on ileal TER, as it was improved (P⩽0.05; 56%) in Zn220-fed pigs compared with ZnC. This study demonstrates that HS progressively compromises the intestinal barrier and supplementing ZnAA at the appropriate dose can improve aspects of small intestinal integrity during severe HS.
The aim of this study was to investigate spatial variation in risk of hospitalization in childhood pneumonia and empyema in the North of England and associated risk factors. Data on childhood (0–14 years) hospital admissions with a diagnosis pneumonia or empyema were linked to postcode districts. Bayesian conditional autoregressive models were used to evaluate spatial variation and the relevance of specific spatial covariates in an area-based study using postcode as the areal unit. There was a sixfold variation in the risk of hospitalization due to pneumonia across the study region. Variation in risk was associated with material deprivation, Child Well-being Index (CWI) health domain score, number of children requiring local authority support, and distance to hospital. No significant spatial variation in risk for empyema was found.
Edited by
Alex S. Evers, Washington University School of Medicine, St Louis,Mervyn Maze, University of California, San Francisco,Evan D. Kharasch, Washington University School of Medicine, St Louis
A method has been developed which will permit the mapping of the genetic material of Pseudomonas aeruginosa. This has been made possible by the use of potassium nitrate in the mating medium and other modifications which have increased the frequency of recombination. In certain circumstances, the ilvA12 marker may be transferred by more than 1% of the donor cells.
FP transfer to recombinant and non-recombinant recipients of Pseudomonas aeruginosa strain I has been investigated under controlled conditions. When transferred to recombinants, the sex factor appeared to enter first and did not seem to be linked to the early chromosome markers. Five to twenty percent of the recipient population were found to be FP+, depending on the time allowed for pairing. Only 40% of the recombinants were FP+ at 90 min. A possible relationship between FP and chromosome has been discussed.