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Vegetation plays an important role in mediating future water resources
Future environmental change is expected to modify the global hydrological cycle, with consequences for the regional distribution of freshwater supplies. Regional precipitation projections, however, differ largely between models, making future water resource projections highly uncertain. Using two representative concentration pathways and nine climate models, we estimate 21st century water resources across Australia, employing both a process-based dynamic vegetation model and a simple hydrological framework commonly used in water resource studies to separate the effects of climate and vegetation on water resources. We show surprisingly robust, pathway-independent regional patterns of change in water resources despite large uncertainties in precipitation projections. Increasing plant water use efficiency (due to the changing atmospheric CO2) and reduced green vegetation cover (due to the changing climate) relieve pressure on water resources for the highly populated, humid coastal regions of eastern Australia. By contrast, in semi-arid regions across Australia, runoff declines are amplified by CO2-induced greening, which leads to increased vegetation water use. These findings highlight the importance of including vegetation dynamics in future water resource projections
Multiband description of the upper critical field of bulk FeSe
The upper critical field of multiband superconductors can be an essential quantity to unravel the nature of
superconducting pairing and its interplay with the electronic structure. Here we experimentally map out the
complete upper critical field phase diagram of FeSe for different magnetic field orientations at temperatures
down to 0.3 K using both resistivity and torque measurements. The temperature dependence of the upper critical
field reflects that of a multiband superconductor and requires a two-band description in the clean limit with band
coupling parameters favoring interband over intraband interactions. Despite the relatively small Maki parameter
in FeSe of α ∼ 1.6, the multiband description of the upper critical field is consistent with the stabilization of
a Fulde-Ferrell-Larkin-Ovchinnikov state below T /Tc ∼ 0.3. We find that the anomalous behavior of the upper
critical field is linked to a departure from the single-band picture, and FeSe provides a clear example of where
multiband effects and the strong anisotropy of the superconducting gap need to be taken into account
Light curves of hydrogen-poor Superluminous Supernovae from the Palomar Transient Factory
We investigate the light-curve properties of a sample of 26 spectroscopically
confirmed hydrogen-poor superluminous supernovae (SLSNe-I) in the Palomar
Transient Factory (PTF) survey. These events are brighter than SNe Ib/c and SNe
Ic-BL, on average, by about 4 and 2~mag, respectively. The peak absolute
magnitudes of SLSNe-I in rest-frame band span ~mag, and these peaks are not powered by radioactive Ni,
unless strong asymmetries are at play. The rise timescales are longer for SLSNe
than for normal SNe Ib/c, by roughly 10 days, for events with similar decay
times. Thus, SLSNe-I can be considered as a separate population based on
photometric properties. After peak, SLSNe-I decay with a wide range of slopes,
with no obvious gap between rapidly declining and slowly declining events. The
latter events show more irregularities (bumps) in the light curves at all
times. At late times, the SLSN-I light curves slow down and cluster around the
Co radioactive decay rate. Powering the late-time light curves with
radioactive decay would require between 1 and 10 of Ni masses.
Alternatively, a simple magnetar model can reasonably fit the majority of
SLSNe-I light curves, with four exceptions, and can mimic the radioactive decay
of Co, up to days from explosion. The resulting spin values do
not correlate with the host-galaxy metallicities. Finally, the analysis of our
sample cannot strengthen the case for using SLSNe-I for cosmology.Comment: 120 pages, 48 figures, 78 tables. ApJ in pres
Acute response to oral calcium loading in pregnant and lactating women with a low calcium intake: A pilot study
Summary: This pilot study in women from The Gambia with low habitual calcium intakes showed differences in calciotropic hormones between pregnant, lactating and non-pregnant, non-lactating women similar to those in Western women. The response to oral calcium loading indicates a high degree of calcium conservation independent of reproductive status. Introduction: In pregnancy and early lactation, parathyroid hormone (PTH) concentrations may be suppressed. Uncertainty exists about how calcium metabolism is regulated, particularly when calcium intake is low. Methods: We investigated fasting markers of calcium metabolism and the acute calcemic and calciuric responses after an oral calcium load in 30 pregnant, lactating or non-pregnant, non-lactating (NPNL) Gambian women with low habitual calcium intakes. Women received 1 g elemental calcium (CaCO3) at 0 min. Blood was collected at −30 and 180 min. Urine was collected from −60 to 0, 0–120 and 120–240 min. Samples were analysed (blood: ionized calcium (iCa); plasma (p): total calcium (tCa), phosphate (P), creatinine (Cr), PTH, 1,25-dihydroxyvitamin D (1,25(OH)2D), osteocalcin (OC), β C-terminal cross-linked telopeptide of type 1 collagen (βCTX), cyclic adenosine monophosphate (cAMP); urine (u): Ca, P, Cr, cAMP). Results: Pre-loading, groups did not differ significantly in iCa, pP, uCa/Cr and uP/Cr. pOC concentrations were significantly lower and NcAMP and p1,25(OH)2D higher in pregnant women; pPTH and pβCTX in lactating women were higher than in NPNL women. Post-loading, iCa, ptCa and uCa/Cr concentrations increased; pPTH, NcAMP, βCTX and uP/Cr decreased in all groups, but the magnitude of change did not differ significantly between groups. Conclusion: Differences between pregnant, lactating and NPNL Gambian women in pPTH, NcAMP and p1,25(OH)2D and bone markers were similar to Western women. However, the response to calcium loading indicates that there may be no differences in renal and intestinal calcium economy associated with reproductive status, potentially due to a high degree of calcium conservation associated with low intakes
Use of a formal consensus development technique to produce recommendations for improving the effectiveness of adult mental health multidisciplinary team meetings
This is the final version of the article. Available from the publisher via the DOI in this record.BACKGROUND: Multidisciplinary team (MDT) meetings are the core mechanism for delivering mental health care but it is unclear which models improve care quality. The aim of the study was to agree recommendations for improving the effectiveness of adult mental health MDT meetings, based on national guidance, research evidence and experiential insights from mental health and other medical specialties. METHODS: We established an expert panel of 16 health care professionals, policy-makers and patient representatives. Five panellists had experience in a range of adult mental health services, five in heart failure services and six in cancer services. Panellists privately rated 68 potential recommendations on a scale of one to nine, and re-rated them after panel discussion using the RAND/UCLA Appropriateness Method to determine consensus. RESULTS: We obtained agreement (median ≥ 7) and low variation in extent of agreement (Mean Absolute Deviation from Median of ≤1.11) for 21 recommendations. These included the explicit agreement and auditing of MDT meeting objectives, and the documentation and monitoring of treatment plan implementation. CONCLUSIONS: Formal consensus development methods that involved learning across specialities led to feasible recommendations for improved MDT meeting effectiveness in a wide range of settings. Our findings may be used by adult mental health teams to reflect on their practice and facilitate improvement. In some other contexts, the recommendations will require modification. For example, in Child and Adolescent Mental Health Services, context-specific issues such as the role of carers should be taken into account. A limitation of the comparative approach adopted was that only five members of the panel of 16 experts were mental health specialists.This report presents independent research commissioned by the National
Institute for Health Research (NIHR). The views and opinions expressed by
authors in this publication are those of the authors and do not necessarily
reflect those of the NHS, the NIHR, MRC, CCF, NETSCC, the Health Services
and Delivery Research programme or the Department of Health
{Interstellar Plasma Weather Effects in Long-term Multi-frequency Timing of Pulsar B1937+21
We report here on variable propagation effects in over twenty years of
multi-frequency timing analysis of pulsar PSR B1937+21 that determine
small-scale properties of the intervening plasma as it drifts through the sight
line. The phase structure function derived from the dispersion measure
variations is in remarkable agreement with that expected from the Kolmogorov
spectrum, with a power law index of , valid over an inferred
scale range of 0.2--50 A.U. The observed flux variation time scale and the
modulation index, along with their frequency dependence, are discrepant with
the values expected from a Kolmogorov spectrum with infinitismally small inner
scale cutoff, suggesting a caustic-dominated regime of interstellar optics.
This implies an inner scale cutoff to the spectrum of
meters. Our timing solutions indicate a transverse velocity of 9 km sec
with respect to the solar system barycenter, and 80 km sec with respect
to the pulsar's LSR. We interpret the frequency dependent variations of DM as a
result of the apparent angular broadening of the source, which is a sensitive
function of frequency (). The error introduced by this in
timing this pulsar is 2.2 s at 1 GHz. The timing error introduced by
``image wandering'' from the slow, nominally refractive scintillation effects
is about 125 nanosec at 1 GHz. The error accumulated due to positional error
(due to image wandering) in solar system barycentric corrections is about 85
nanosec at 1 GHz.Comment: Accepted for publication in the Astrophysical Journa
Determinants of treatment plan implementation in multidisciplinary team meetings for patients with chronic diseases: a mixed-methods study.
This is the final version of the article. Available from the publisher via the DOI in this record.OBJECTIVE: Multidisciplinary team (MDT) meetings are assumed to produce better decisions and are extensively used to manage chronic disease in the National Health Service (NHS). However, evidence for their effectiveness is mixed. Our objective was to investigate determinants of MDT effectiveness by examining factors influencing the implementation of MDT treatment plans. This is a proxy measure of effectiveness, because it lies on the pathway to improvements in health, and reflects team decision making which has taken account of clinical and non-clinical information. Additionally, this measure can be compared across MDTs for different conditions. METHODS: We undertook a prospective mixed-methods study of 12 MDTs in London and North Thames. Data were collected by observation of 370 MDT meetings, interviews with 53 MDT members, and from 2654 patient medical records. We examined the influence of patient-related factors (disease, age, sex, deprivation, whether their preferences and other clinical/health behaviours were mentioned) and MDT features (as measured using the 'Team Climate Inventory' and skill mix) on the implementation of MDT treatment plans. RESULTS: The adjusted odds (or likelihood) of implementation was reduced by 25% for each additional professional group represented at the MDT meeting. Implementation was more likely in MDTs with clear goals and processes and a good 'Team Climate' (adjusted OR 1.96; 95% CI 1.15 to 3.31 for a unit increase in Team Climate Inventory (TCI) score). Implementation varied by disease category, with the lowest adjusted odds of implementation in mental health teams. Implementation was also lower for patients living in more deprived areas (adjusted odds of implementation for patients in the most compared with least deprived areas was 0.60, 95% CI 0.39 to 0.91). CONCLUSIONS: Greater multidisciplinarity is not necessarily associated with more effective decision making. Explicit goals and procedures are also crucial. Decision implementation should be routinely monitored to ensure the equitable provision of care.This project was funded by the NIHR Health Services
and Delivery Research programme (project number 09/2001/
04) and will be published in full in the Health Services and
Delivery Research Journal. Further information available at:
(http://www.netscc.ac.uk/hsdr/projdetails.php?ref=09-2001-04).
In accordance with NIHR regulations, the findings reported
here are to be referred to as initial until the NIHR final report
has been published. The sponsors of the study had no role in
study design, data collection, data analysis, data interpretation,
the writing of the report, or the decision to submit the report
for publication
Predictors of 25(OH)D half-life and plasma 25(OH)D concentration in The Gambia and the UK
Summary: Predictors of 25(OH)D3 half-life were factors associated with vitamin D metabolism, but were different between people in The Gambia and the UK. Country was the strongest predictor of plasma 25(OH)D concentration, probably as a marker of UVB exposure. 25(OH)D3 half-life may be applied as a tool to investigate vitamin D expenditure. Introduction: The aim of this study was to investigate predictors of 25(OH)D3 half-life and plasma 25(OH)D concentration. Methods: Plasma half-life of an oral tracer dose of deuterated-25(OH)D3 was measured in healthy men aged 24–39 years, resident in The Gambia, West Africa (n = 18) and in the UK during the winter (n = 18), countries that differ in calcium intake and vitamin D status. Plasma and urinary markers of vitamin D, calcium, phosphate and bone metabolism, nutrient intakes and anthropometry were measured. Results: Normally distributed data are presented as mean (SD) and non-normal data as geometric mean (95 % CI). Gambian compared to UK men had higher plasma concentrations of 25(OH)D (69 (13) vs. 29 (11) nmol/L; P < 0.0001); 1,25(OH)2D (181 (165, 197) vs. 120 (109, 132) pmol/L; P < 0.01); and parathyroid hormone (PTH) (50 (42, 60) vs. 33 (27, 39); P < 0.0001). There was no difference in 25(OH)D3 half-life (14.7 (3.5) days vs. 15.6 (2.5) days) between countries (P = 0.2). In multivariate analyses, 25(OH)D, 1,25(OH)2D, vitamin D binding protein and albumin-adjusted calcium (Caalb) explained 79 % of variance in 25(OH)D3 half-life in Gambians, but no significant predictors were found in UK participants. For the countries combined, Caalb, PTH and plasma phosphate explained 39 % of half-life variability. 1,25(OH)2D, weight, PTH and country explained 81 % of variability in 25(OH)D concentration; however, country alone explained 74 %. Conclusion: Factors known to affect 25(OH)D metabolism predict 25(OH)D3 half-life, but these differed between countries. Country predicted 25(OH)D, probably as a proxy measure for UVB exposure and vitamin D supply. This study supports the use of 25(OH)D half-life to investigate vitamin D metabolism
Interleukin 7 from Maternal Milk Crosses the Intestinal Barrier and Modulates T- Cell Development in Offspring
Background
Breastfeeding protects against illnesses and death in hazardous environments, an
effect partly mediated by improved immune function. One hypothesis suggests that
factors within milk supplement the inadequate immune response of the offspring,
but this has not been able to account for a series of observations showing that
factors within maternally derived milk may supplement the development of the
immune system through a direct effect on the primary lymphoid organs. In a
previous human study we reported evidence suggesting a link between IL-7 in
breast milk and the thymic output of infants. Here we report evidence in mice of
direct action of maternally-derived IL-7 on T cell development in the offspring.
Methods and Findings
We have used recombinant IL-7 labelled with a fluorescent dye to trace the
movement in live mice of IL-7 from the stomach across the gut and into the
lymphoid tissues. To validate the functional ability of maternally derived IL-
7 we cross fostered IL-7 knock-out mice onto normal wild type mothers. Subsets
of thymocytes and populations of peripheral T cells were significantly higher
than those found in knock-out mice receiving milk from IL-7 knock-out mothers.
Conclusions/Significance Our study provides direct evidence that interleukin 7,
a factor which is critical in the development of T lymphocytes, when maternally
derived can transfer across the intestine of the offspring, increase T cell
production in the thymus and support the survival of T cells in the peripheral
secondary lymphoid tissue
The Fire Modeling Intercomparison Project (FireMIP), phase 1: experimental and analytical protocols
The important role of fire in regulating vegetation community composition and contributions to emissions of greenhouse gases and aerosols make it a critical component of dynamic global vegetation models and Earth system models. Over two decades of development, a wide variety of model structures and mechanisms have been designed and incorporated into global fire models, which have been linked to different vegetation models. However, there has not yet been a systematic examination of how these different strategies contribute to model performance. Here we describe the structure of the first phase of the Fire Model Intercomparison Project (FireMIP), which for the first time seeks to systematically compare a number of models. By combining a standardized set of input data and model experiments with a rigorous comparison of model outputs to each other
and to observations, we will improve the understanding of what drives vegetation fire, how it can best be simulated, and what new or improved observational data could allow better constraints on model behavior. Here we introduce the fire models used in the first phase of FireMIP, the simulation protocols applied, and the benchmarking system used to evaluate the models
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