2,558 research outputs found
Heterogeneity in CO/CO Ratios Toward Solar-Type Young Stellar Objects
This study reports an unusual heterogeneity in
[CO]/[CO] abundance ratios of carbon monoxide
observed in the gas phase toward seven ~ solar-mass YSOs and three dense
foreground clouds in the nearby star-forming regions, Ophiuchus, Corona
Australis, Orion, Vela and an isolated core, L43. Robust isotope ratios were
derived using infrared absorption spectroscopy of the 4.7 m fundamental
and 2.3 m overtone rovibrational bands of CO at very high resolution
(/), observed with the CRIRES
spectrograph on the Very Large Telescope. We find
[CO]/[CO] values ranging from ~ 85 to 165,
significantly higher than those of the local interstellar medium (~ 65 to 69).
These observations are evidence for isotopic heterogeneity in carbon reservoirs
in solar-type YSO environments, and encourage the need for refined Galactic
chemical evolution models to explain the C/C discrepancy between
the solar system and local ISM. The oxygen isotope ratios are consistent with
isotopologue-specific photodissociation by CO self-shielding toward the disks,
VV CrA N and HL Tau, further substantiating models predicting CO self-shielding
on disk surfaces. However, we find that CO self-shielding is an unlikely
general explanation for the high [CO]/[CO] ratios
observed in this study. Comparison of the solid CO against gas-phase
[CO]/[CO] suggests that interactions between CO ice
and gas reservoirs need to be further investigated as at least a partial
explanation for the unusually high [CO]/[CO]
observed.Comment: 16 pages, 14 figures, 7 tables. Accepted for publication in The
Astrophysical Journa
Strength of association between umbilical cord pH and perinatal and long term outcomes: systematic review and meta-analysis
Objective To evaluate the association between umbilical cord pH at birth and long term outcomes
Mary Crosse project: systematic reviews and grading the value of neonatal tests in predicting long term outcomes
<p>Abstract</p> <p>Background</p> <p>Events before birth, condition at birth, events immediately following birth, and condition in early childhood are linked together, and have implications for health and disease in adulthood. At present, there is lack of clarity about the tests that purport to link these various stages. This is partly because there is paucity of collated information about the best strategies for predicting longer-term outcomes before (using tests in fetal period) or after birth (using tests in neonatal period, infancy as well as early childhood).</p> <p>Methods/Design</p> <p>A series of systematic reviews and meta-analyses will be undertaken to determine, amongst neonates, the ability of various tests and measures to predict infant, childhood and adult outcomes. We will search Medline, Embase, Cochrane Library, MEDION, citation lists of review articles and eligible primary articles and will contact experts in the field. Independent reviewers will select studies, extract data and assess study quality according to established criteria. Language restrictions will not be applied. Data synthesis will involve meta-analysis (where appropriate), exploration of heterogeneity and publication bias. Evidence collated will be graded for its quality to support decision making.</p> <p>Discussion</p> <p>The project will collate, synthesise and evaluate the available evidence concerning the value of tests of neonatal wellbeing to predict long term outcomes. The systematic reviews will assess the quality of available evidence and identify tests with the strongest association with outcomes, and assess their economic value. The output of this project will help formulate practice recommendations.</p
Does case management for patients with heart failure based in the community reduce unplanned hospital admissions?:A systematic review and meta-analysis
An investment case analysis for the prevention and treatment of adolescent mental disorders and suicide in England
BackgroundAdolescent mental health (AMH) needs in England have increased dramatically and needs exceed treatment availability. This study undertook a comparative assessment of the health and economic return on investment (ROI) of interventions to prevent and treat mental disorders among adolescents (10–19 years) and examined intervention affordability and readiness.MethodsInterventions were identified following a review of published and grey literature. A Markov model followed a simulated adolescent cohort to estimate implementation costs and health, education, and economic benefits. Intervention affordability was assessed, comparing annual cost per adolescent with NHS England per capita spending, and an expert panel assessed intervention readiness using a validated framework.ResultsOver 10- and 80-year horizons, interventions to treat mild anxiety and mild depression were most cost-effective, with the highest individual lifetime ROI (GBP 5822 GBP 1 and GBP 257: GBP 1). Preventing anxiety and depression was most affordable and ‘implementation ready’ and offered the highest health and economic benefits. A priority package (anxiety and depression prevention; mild anxiety and mild depression treatment) would avert 5 million disability-adjusted life-years (DALYS) and achieve an ROI of GBP 15: GBP 1 over 10 years or 11.5 million DALYs (ROI of GBP 55: GBP 1) over 80 years.ConclusionThe economic benefits from preventing and treating common adolescent mental disorders equivalent to 25% of NHS England’s annual spending in 2021 over 10 years and 91% over 80 years. Preventing and early treatment for anxiety and depression had the highest ROIs and strong implementation readiness.<br/
High-Precision C^(17)O, C^(18)O, and C^(16)O Measurements in Young Stellar Objects: Analogues for CO Self-shielding in the Early Solar System
Using very high resolution (λ/Δλ ≈ 95 000) 4.7 μm fundamental and 2.3 μm overtone rovibrational CO absorption spectra obtained with the Cryogenic Infrared Echelle Spectrograph infrared spectrometer on the Very Large Telescope (VLT), we report detections of four CO isotopologues—C^(16)O, ^(13)CO, C^(18)O, and the rare species, C^(17)O—in the circumstellar environment of two young protostars: VV CrA, a binary T Tauri star in the Corona Australis molecular cloud, and Reipurth 50, an intermediate-mass FU Ori star in the Orion Molecular Cloud. We argue that the observed CO absorption lines probe a protoplanetary disk in VV CrA, and a protostellar envelope in Reipurth 50. All CO line profiles are spectrally resolved, with intrinsic line widths of ≈3-4 km s^(–1) (FWHM), permitting direct calculation of CO oxygen isotopologue ratios with 5%-10% accuracy. The rovibrational level populations for all species can be reproduced by assuming that CO absorption arises in two temperature regimes. In the higher temperature regime, in which the column densities are best determined, the derived oxygen isotope ratios in VV CrA are: [C^(16)O]/[C^(18)O] =690 ± 30; [C^(16)O]/[C^(17)O] =2800 ± 300, and [C^(18)O]/[C^(17)O]=4.1 ± 0.4. For Reipurth 50, we find [C^(16)O]/[C^(18)O] =490 ± 30; [C^(16)O]/[C^(17)O] =2200 ± 150, [C^(18)O]/[C^(17)O] = 4.4 ± 0.2. For both objects, ^(12)C/^(13)C are on the order of 100, nearly twice the expected interstellar medium (ISM) ratio. The derived oxygen abundance ratios for the VV CrA disk show a significant mass-independent deficit of C^(17)O and C^(18)O relative to C^(16)O compared to ISM baseline abundances. The Reipurth 50 envelope shows no clear differences in oxygen CO isotopologue ratios compared with the local ISM. A mass-independent fractionation can be interpreted as being due to selective photodissociation of CO in the disk surface due to self-shielding. The deficits in C^(17)O and C^(18)O in the VV CrA protoplanetary disk are consistent with an analogous origin of the ^(16)O variability in the solar system by isotope selective photodissociation, confirmation of which may be obtained via study of additional sources. The higher fractionation observed for the VV CrA disk compared with the Reipurth 50 envelope is likely due to a combination of disk geometry, grain growth, and vertical mixing processes
Evaluation of the Electronic Clinical Dementia Rating for dementia screening
IMPORTANCE: The Clinical Dementia Rating (CDR) is a well-validated instrument widely used to detect and stage dementia due to Alzheimer disease. The digital Electronic Clinical Dementia Rating (eCDR) can be remotely self-administered and automatically scored, with potential to facilitate efficient dementia screening and staging.
OBJECTIVE: To evaluate the association of the eCDR with the CDR and other in-clinic assessments for screening older adults for cognitive impairment.
DESIGN, SETTING, AND PARTICIPANTS: This multisite, cross-sectional study used baseline data from a longitudinal, observational study from 2020 to 2023, including up to 3 years of follow-up. Participants were enrolled from 3 Alzheimer Disease Research Centers and the Brain Health Registry. Participants (aged ≥55 years, with a study partner, and no acute or unstable major medical conditions) were recruited during in-clinic visits or by automated emails.
EXPOSURES: Participants completed the Uniform Data Set Version 3 (UDS; including the CDR) in supervised clinical research settings, and then completed the eCDR remotely, online and unsupervised, using their own device.
MAIN OUTCOMES AND MEASURES: The primary outcomes were eCDR scores (item; categorical box and global; continuous box and global), CDR scores (item; categorical box and global), and UDS assessment scores. Associations were evaluated using linear and logistic regressions.
RESULTS: A total of 3565 participants were contacted, and 288 were enrolled. Among 173 participants with item-level data (mean [SD] age, 70.84 [7.65] years; 76 women [43.9%]), eCDR to CDR concordance was 90% or higher for 33 items (63%) and 70% to 89% for 13 items (25%). Box (domain) level concordance ranged from 80% (memory) to 99% (personal care). The global score concordance rate was 81%. κ statistics were fair to moderate. Among 206 participants with box and global scores (mean [SD] age, 71.34 [7.68] years; 95 women [46.1%]), eCDR continuous global score was associated with CDR global (categorical) score with an area under the receiver operating characteristic curve of 0.79 (95% CI, 0.70-0.87). Correlations between eCDR and in-clinic UDS assessments were similar to those between CDR sum of box scores and the same in-clinic assessments.
CONCLUSIONS AND RELEVANCE: These findings suggest that the eCDR is valid and has potential use for screening and assessment of older adults for cognitive and functional decline related to Alzheimer disease. Instrument optimization and validation in diverse cohorts in remote settings are crucial for evaluating scalability and eCDR utility in clinical research, trials, and health care settings
Identifying and designing for the needs of older road users
The number of older road users is continuously increasing over time. Whilst much
research focuses on the likely impact on road safety, little work has been carried out
examining the impact on older people themselves of their declining ability to cope with
the road environment. Additionally, it is known that because of their increased frailty
older drivers are more at risk of sustaining a fatal or serious injury than younger roadusers.
Consequently older people often feel pressured by family members, health
practitioners or an increasing inability to deal with traffic conditions, into giving up driving
in favour of some other form of transport. However, the subsequent effect of this may
actually be to increase the risk exposure of older people. The aim of this study was to
use an accident-independent approach to collect detailed information on the interaction
between behaviour, perceived and actual risk and use of transport systems, using both
quantitative and qualitative techniques. A focus group and interviews were conducted
with older road-users to gain an initial insight into their experiences and perceptions of
safety whilst using the UK road infrastructure (including roads, pavements, cycle tracks,
pedestrian crossings etc.). Additionally, analysis was undertaken of UK exposure data
and casualty rates for older road users. The qualitative and quantitative data sources
were compared and contrasted. Older people felt at risk using the road system, and
many of these perceptions were upheld according to the statistical reports. Not all of the
issues raised by older road-users can be dealt with by improving design, but this study
presents a set of recommendations, which, if implemented would increase the safety of
all road users
Educational Brochures Influence Beliefs and Knowledge Regarding Exercise during Pregnancy: A Pilot Study
International Journal of Exercise Science 12(3): 581-589, 2019. Women who are pregnant report receiving little or no advice about physical activity during pregnancy from their obstetric provider. The purpose of this study was to assess the effectiveness of an evidence-based educational brochure on both immediate and two-week retention of knowledge about exercise during pregnancy. Thirty-two women of childbearing age (age: 25.0 ± 4.0 years, body mass index: 29.5 ± 6.5 kg/m2, 93.7% Caucasian, 83.4% had at least some college) completed a survey before exposure to an evidence-based educational brochure regarding exercise during pregnancy. Post surveys were taken immediately after viewing the educational brochure and again 2-weeks later. After exposure to educational brochures, survey scores on both surveys were significantly higher immediately-post and two-weeks post compared to baseline survey scores (Survey 1 (assessing beliefs) – pre: 79.2 ± 8.9%, post: 92.6 ± 7.4%, 2-weeks post: 92.0 ± 6.5%, p \u3c 0.001; Survey 2 (assessing knowledge) – pre: 65.3 ± 16.4%, post: 81.3 ± 14.9%, 2-weeks post: 78.8 ± 12.4%, p \u3c 0.001). No significant differences detected between immediate post and 2-weeks post for either Survey 1 (p = 0.72) or Survey 2 (p = 0.52); suggesting the information was retained. An evidence-based educational brochure is effective for improving and retaining information 2-weeks later regarding exercise during pregnancy. However, replication studies in more diverse populations are needed to confirm the results of this pilot study. The long-term goal for this line of research is to urge health care providers to consider providing patients with educational information in order to improve knowledge and patient-provider communication on this topic
Development of the research lifecycle model for library services
Can the niche services of individual librarians across multiple libraries be developed into a suite of standard services available to all scientists that support the entire research lifecycle
- …