426 research outputs found
Anthropogenically forced change in aquatic ecosystems: Reflections on the use of monitoring, archival and palaeolimnological data to inform conservation
The open collection “Aquatic transitions: Tracking the nature and trajectories of anthropogenically forced change in freshwater and coastal ecosystems” stems from a session of the same name at the ASLO (Association for the Sciences of Limnology and Oceanography) Aquatic Sciences Meeting 2017 in Honolulu, Hawai'i. The five papers gathered here reflect the focus of the special session on long-term ecosystem research and monitoring (LTERM), and collectively make use of monitoring data, palaeolimnology, and historical and documentary records to explore the timing, extent, and causes of human-related impacts on aquatic ecosystems. Collectively, they demonstrate that because timescales of ecological change often extend beyond contemporary monitoring, LTERM plays a crucial role in supporting evidence-based conservation. In this introduction, we reflect on the role that LTERM has had in each of the ecosystems studied, and discuss the opportunities for LTERM work to inform future conservation
Garnet–monazite rare earth element relationships in sub-solidus metapelites: a case study from Bhutan
A key aim of modern metamorphic geochronology is to constrain precise and accurate rates and timescales of tectonic processes. One promising approach in amphibolite and granulite-facies rocks links the geochronological information recorded in zoned accessory phases such as monazite to the pressure–temperature information recorded in zoned major rock-forming minerals such as garnet. Both phases incorporate rare earth elements (REE) as they crystallize and their equilibrium partitioning behaviour potentially provides a useful way of linking time to temperature. We report REE data from sub-solidus amphibolite-facies metapelites from Bhutan, where overlapping ages, inclusion relationships and Gd/Lu ratios suggest that garnet and monazite co-crystallized. The garnet–monazite REE relationships in these samples show a steeper pattern across the heavy (H)REE than previously reported. The difference between our dataset and the previously reported data may be due to a temperature-dependence on the partition coefficients, disequilibrium in either dataset, differences in monazite chemistry or the presence or absence of a third phase that competed for the available REE during growth. We urge caution against using empirically-derived partition coefficients from natural samples as evidence for, or against, equilibrium of REE-bearing phases until monazite–garnet partitioning behaviour is better constrained
Core Health Outcomes In Childhood Epilepsy (CHOICE):Protocol for the selection of a core outcome set
This is the final version of the article. Available from BioMed Central via the DOI in this record.BACKGROUND: There is increasing recognition that establishing a core set of outcomes to be evaluated and reported in trials of interventions for particular conditions will improve the usefulness of health research. There is no established core outcome set for childhood epilepsy. The aim of this work is to select a core outcome set to be used in evaluative research of interventions for children with rolandic epilepsy, as an exemplar of common childhood epilepsy syndromes. METHODS: First we will identify what outcomes should be measured; then we will decide how to measure those outcomes. We will engage relevant UK charities and health professional societies as partners, and convene advisory panels for young people with epilepsy and parents of children with epilepsy. We will identify candidate outcomes from a search for trials of interventions for childhood epilepsy, statutory guidance and consultation with our advisory panels. Families, charities and health, education and neuropsychology professionals will be invited to participate in a Delphi survey following recommended practices in the development of core outcome sets. Participants will be able to recommend additional outcome domains. Over three rounds of Delphi survey participants will rate the importance of candidate outcome domains and state the rationale for their decisions. Over the three rounds we will seek consensus across and between families and health professionals on the more important outcomes. A face-to-face meeting will be convened to ratify the core outcome set. We will then review and recommend ways to measure the shortlisted outcomes using clinical assessment and/or patient-reported outcome measures. DISCUSSION: Our methodology is a proportionate and pragmatic approach to expediently produce a core outcome set for evaluative research of interventions aiming to improve the health of children with epilepsy. A number of decisions have to be made when designing a study to develop a core outcome set including defining the scope, choosing which stakeholders to engage, most effective ways to elicit their views, especially children and a potential role for qualitative research.This study is part of Changing Agendas on Sleep, Treatment and Learning in Childhood Epilepsy (CASTLE), which is funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research RP-PG-0615-20007
Placental Pathology in Spontaneous and Iatrogenic Preterm Birth: Different Entities With Unique Pathologic Features
INTRODUCTION: Placental pathology is an important contributor to the understanding of preterm birth and reveals major differences between spontaneous preterm birth (SPTB) and iatrogenic preterm birth (IPTB). The aim of this study was to investigate these relationships.
METHODS: Research midwives collected placentas from 1101 women with singleton pregnancies who were enrolled in the Safe Passage Study. Trained pathology technologists prepared and processed placenta specimens for macroscopic and microscopic examination by designated pathologists. Statistical analyses were done with STATISTICA version 13.
RESULTS: In SPTB we found more cases of accelerated villous maturation; however, the other features of maternal vascular malperfusion (MVM) were not present. The prevalence rate of funisitis was also increased. In IPTB, multiple features of MVM - accelerated villous maturation, distal villous hypoplasia, decidual arteriopathy, increased syncytial knots, increased perivillous fibrin, and prominent extravillous trophoblast were increased, as were features of fetal vascular malperfusion (FVM) - umbilical cord vessel thrombosis, avascular villi, and fetal vascular thrombosis. Increased syncytial knots were found in 26% of preterm stillbirths and in 29% of preterm infant demises as compared to 81% of IPTB infants alive at one year.
DISCUSSION: SPTB and IPTB differ. The detected abnormal accelerated villous maturation pattern in SPTB and preterm demises, suggests an inability of the placenta to adapt and may be a trigger for SPTB. Funisitis was the only inflammatory response significant for SPTB. MVM and FVM are implicated in IPTB, but not an inflammatory process
Parents and GPs’ understandings and beliefs about food allergy testing in children with eczema:qualitative interview study within the Trial of Eczema allergy Screening Tests (TEST) feasibility trial
Aim To explore parent and general practitioner (GP) understanding and beliefs about food allergy testing for children with eczema.Design and setting Qualitative interview study in UK primary care within the Trial of Eczema allergy Screening Tests feasibility trial.Participants Semi-structured interviews with parents of children with eczema taking part in the feasibility study and GPs at practices hosting the study.Results 21 parents and 11 GPs were interviewed. Parents discussed a range of potential causes for eczema, including a role for food allergy. They believed allergy testing to be beneficial as it could potentially identify a cure or help reduce symptoms and they found negative tests reassuring, suggesting to them that no dietary changes were needed. GPs reported limited experience and uncertainty regarding food allergy in children with eczema. While some GPs believed referral for allergy testing could be appropriate, most were unclear about its utility. They thought it should be reserved for children with severe eczema or complex problems but wanted more information to advise parents and help guide decision making.Conclusions Parents’ motivations for allergy testing are driven by the desire to improve their child’s condition and exclude food allergy as a possible cause of symptoms. GPs are uncertain about the role of allergy testing and want more information about its usefulness to support parents and help inform decision making.Trial registration number ISRCTN15397185
The VAST Survey - I. Companions and the unexpected X-ray detection of B6-A7 stars
With an adaptive optics imaging survey of 148 B6-A7 stars, we have tested the
hypothesis that unresolved lower-mass companions are the source of the
unexpected X-ray detections of stars in this spectral type range. The sample is
composed of 63 stars detected in X-rays within the ROSAT All-Sky Survey and 85
stars that form a control sample; both subsets have the same restricted
distribution of spectral type, age, X-ray sensitivity and separation coverage.
A total of 68 companion candidates are resolved with separations ranging from
0.3" to 26.2", with 23 new detections. The multiple star frequency of the X-ray
sample based on companions resolved within the ROSAT error ellipse is found to
be 43 (+6,-6)%. The corresponding control sample multiple star frequency is
three times lower at 12 (+4,-3)% -- a difference of 31\pm7%. These results are
presented in the first of a series of papers based on our Volume-limited A-Star
(VAST) survey -- a comprehensive study of the multiplicity of A-type stars.Comment: Accepted for publication in Monthly Notices of the Royal Astronomical
Societ
Using lake sediments to assess the long-term impacts of anthropogenic activity in tropical river deltas
Tropical river deltas, and the social-ecological systems they sustain, are changing rapidly due to anthropogenic activity and climatic change. Baseline data to inform sustainable management options for resilient deltas is urgently needed and palaeolimnology (reconstructing past conditions from lake or wetland deposits) can provide crucial long-term perspectives needed to identify drivers and rates of change. We review how palaeolimnology can be a valuable tool for resource managers using three current issues facing tropical delta regions: hydrology and sediment supply, salinisation and nutrient pollution. The unique ability of palaeolimnological methods to untangle multiple stressors is also discussed. We demonstrate how palaeolimnology has been used to understand each of these issues, in other aquatic environments, to be incorporated into policy. Palaeolimnology is a key tool to understanding how anthropogenic influences interact with other environmental stressors, providing policymakers and resource managers with a ‘big picture’ view and possible holistic solutions that can be implemented
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