3,184 research outputs found
Non-immune fetal hydrops: etiology and outcome according to gestational age at diagnosis.
OBJECTIVE: Fetal hydrops is associated with increased perinatal morbidity and mortality. The etiology and outcome of fetal hydrops may differ according to the gestational age at diagnosis. The aim of this study was to evaluate the cause, evolution and outcome of non-immune fetal hydrops (NIFH), according to the gestational age at diagnosis. METHODS: This was a retrospective cohort study of all singleton pregnancies complicated by NIFH, at the Fetal Medicine Unit at St George's University Hospital, London, UK, between 2000 and 2018. All fetuses had detailed anomaly and cardiac ultrasound scans, karyotyping and infection screening. Prenatal diagnostic and therapeutic intervention, gestational age at diagnosis and delivery, as well as pregnancy outcome, were recorded. Regression analysis was used to test for potential association between possible risk factors and perinatal mortality. RESULTS: We included 273 fetuses with NIFH. The etiology of the condition varied significantly in the three trimesters. Excluding 30 women who declined invasive testing, the cause of NIFH was defined as unknown in 62 of the remaining 243 cases (25.5%). Chromosomal aneuploidy was the most common cause of NIFH in the first trimester. It continued to be a significant etiologic factor in the second trimester, along with congenital infection. In the third trimester, the most common etiology was cardiovascular abnormality. Among the 152 (55.7%) women continuing the pregnancy, 48 (31.6%) underwent fetal intervention, including the insertion of pleuroamniotic shunts, fetal blood transfusion and thoracentesis. Fetal intervention was associated significantly with lower perinatal mortality (odds ratio (OR), 0.30 (95% CI, 0.14-0.61); P 0.05). CONCLUSIONS: An earlier gestational age at diagnosis of NIFH was associated with an increased risk of aneuploidy and worse pregnancy outcome, including a higher risk of perinatal loss. Fetal therapy was associated significantly with lower perinatal mortality. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology
Atomic environments in iron meteorites using EXAFS
Extended x ray absorption fine structure (EXAFS) is observed as a modulation on the high energy side of an x ray absorption edge. It occurs when the photo-ejected electron wave is scattered by neighboring atoms in a solid, and interference occurs between the outgoing and scattered waves. The result is that the absorption spectrum carries a signature that is characteristic of the identity and disposition of scattering atoms around the absorbing atom. Therefore, it may be shown that the Fourier transform of the normalized EXAFS can provide detailed information about the immediate environment of specific atoms in a solid and is ideally suited to the study of cosmic dusts. A study of cosmic dust was initiated using EXAFS and other techniques. The simplest type of cosmic material, namely iron meteorites, was investigated
Antigen depot is not required for alum adjuvanticity
Alum adjuvants have been in continuous clinical use for more than 80 yr. While the prevailing theory has been that depot formation and the associated slow release of antigen and/or inflammation are responsible for alum enhancement of antigen presentation and subsequent T- and B-cell responses, this has never been formally proven. To examine antigen persistence, we used the chimeric fluorescent protein EαGFP, which allows assessment of antigen presentation in situ, using the Y-Ae antibody. We demonstrate that alum and/or CpG adjuvants induced similar uptake of antigen, and in all cases, GFP signal did not persist beyond 24 h in draining lymph node antigen-presenting cells. Antigen presentation was first detectable on B cells within 6–12 h of antigen administration, followed by conventional dendritic cells (DCs) at 12–24 h, then finally plasmacytoid DCs at 48 h or later. Again, alum and/or CpG adjuvants did not have an effect on the magnitude or sequence of this response; furthermore, they induced similar antigen-specific T-cell activation in vivo. Notably, removal of the injection site and associated alum depot, as early as 2 h after administration, had no appreciable effect on antigen-specific T- and B-cell responses. This study clearly rules out a role for depot formation in alum adjuvant activity
Tuning into the Future: Informal Learning and Music Education
When adolescents are engaged in learning, research has shown a decrease in alcohol and drug use, higher retention rates and fewer failures throughout high school, lower rates of depression as well as lower rates of anti-social and criminal behaviours. Attention to student engagement with a priority on 21st century learning skills requires the examination of various pedagogies, including using informal learning practices as the foundation for instruction with adolescents in schools.
This pilot project targets Grade 7 to 10 students in two school settings where adolescent engagement is a priority; it examines the viability of implementing informal learning practices within the Canadian context
Conductivity in organic semiconductors hybridized with the vacuum field
Organic semiconductors have generated considerable interest for their
potential for creating inexpensive and flexible devices easily processed on a
large scale [1-11]. However technological applications are currently limited by
the low mobility of the charge carriers associated with the disorder in these
materials [5-8]. Much effort over the past decades has therefore been focused
on optimizing the organisation of the material or the devices to improve
carrier mobility. Here we take a radically different path to solving this
problem, namely by injecting carriers into states that are hybridized to the
vacuum electromagnetic field. These are coherent states that can extend over as
many as 10^5 molecules and should thereby favour conductivity in such
materials. To test this idea, organic semiconductors were strongly coupled to
the vacuum electromagnetic field on plasmonic structures to form polaritonic
states with large Rabi splittings ca. 0.7 eV. Conductivity experiments show
that indeed the current does increase by an order of magnitude at resonance in
the coupled state, reflecting mostly a change in field-effect mobility as
revealed when the structure is gated in a transistor configuration. A
theoretical quantum model is presented that confirms the delocalization of the
wave-functions of the hybridized states and the consequences on the
conductivity. While this is a proof-of-principle study, in practice
conductivity mediated by light-matter hybridized states is easy to implement
and we therefore expect that it will be used to improve organic devices. More
broadly our findings illustrate the potential of engineering the vacuum
electromagnetic environment to modify and to improve properties of materials.Comment: 16 pages, 13 figure
Multiple myeloma can be accurately diagnosed in acute kidney injury patients using a rapid serum free light chain test
New mobilities across the lifecourse: A framework for analysing demographically-linked drivers of migration
Date of acceptance: 17/02/2015Taking the life course as the central concern, the authors set out a conceptual framework and define some key research questions for a programme of research that explores how the linked lives of mobile people are situated in time–space within the economic, social, and cultural structures of contemporary society. Drawing on methodologically innovative techniques, these perspectives can offer new insights into the changing nature and meanings of migration across the life course.Publisher PDFPeer reviewe
Patient level pooled analysis of 68,500 patients from seven major vitamin D fracture trials in the US and Europe
Objectives To identify participants’ characteristics that influence the anti-fracture efficacy of vitamin D or vitamin
D plus calcium with respect to any fracture, hip fracture, and clinical vertebral fracture and to assess the influence of dosing regimens and co-administration of calcium. Design Individual patient data analysis using pooled data from randomised trials. Data sources Seven major randomised trials of vitamin D with calcium or vitamin D alone, yielding a total of 68 517 participants (mean age 69.9 years, range 47-107 years, 14.7% men). Study selection Studies included were randomised studies with at least one intervention arm in which vitamin D was given, fracture as an outcome, and at least 1000 participants. Data synthesis Logistic regression analysis was used to identify significant interaction terms, followed by Cox’s proportional hazards models incorporating age, sex, fracture history, and hormone therapy and bisphosphonate use. Results Trials using vitamin D with calcium showed a
reduced overall risk of fracture (hazard ratio 0.92, 95% confidence interval 0.86 to 0.99, P=0.025) and hip fracture (all studies: 0.84, 0.70 to 1.01, P=0.07; studies using 10 μg of vitamin D given with calcium: 0.74, 0.60 to 0.91, P=0.005). For vitamin D alone in daily doses of 10 μg or 20 μg, no significant effects were found. No interaction was found between fracture history and treatment
response, nor any interaction with age, sex, or hormone replacement therapy. Conclusion This individual patient data analysis indicates that vitamin D given alone in doses of 10-20 μg is not effective in preventing fractures. By contrast, calcium and vitamin D given together reduce hip fractures and total fractures, and probably vertebral fractures, irrespective of age, sex, or previous fractures.The WHI program is funded by the National Heart, Lung, and Blood Institute, National Institutes of Health, US Department of Health and Human Services through contracts N01WH22110, 24152, 32100-2, 32105-6, 32108-9, 32111-13, 32115, 32118-32119, 32122, 42107-26, 42129-32, and 44221. AA acknowledges personal funding from the UK Medical Research Council and Chief Scientist Office of the Scottish Government Health Directorates
Leveraging Existing Technology: Developing a Trusted Digital Repository for the U.S. Geological Survey
As Federal Government agencies in the United States pivot to increase access to scientific data (Sheehan, 2016), the U.S. Geological Survey (USGS) has made substantial progress (Kriesberg et al., 2017). USGS authors are required to make federally funded data publicly available in an approved data repository (USGS, 2016b). This type of public data product, known as a USGS data release, serves as a method for publishing reviewed and approved data. In this paper, we present major milestones in the approach the USGS took to transition an existing technology platform to a Trusted Digital Repository. We describe both the technical and the non-technical actions that contributed to a successful outcome.We highlight how initial workflows revealed patterns that were later automated, and the ways in which assessments and user feedback influenced design and implementation. The paper concludes with lessons learned, such as the importance of a community of practice, application programming interface (API)-driven technologies, iterative development, and user-centered design. This paper is intended to offer a potential roadmap for organizations pursuing similar goals.
 
Pinpointing deep geothermal upflow in zones of complex tectono-volcanic degassing : new insights from Aluto volcano, Main Ethiopian Rift
The project was financed in the framework of the Volkswagen Foundation’s „Postdoctoral Fellowships for African Researchers in the Engineering Sciences“ (Reference: 90017).Active rifts release large amounts of gases from deep sources to the atmosphere by advection and diffusion processes along permeable fracture zones. The objective of this study is to develop geothermal exploration concepts for areas with little or no hydrothermal surface expressions suitable for fluid sampling and analyses (e.g., hot springs, geysers, and fumaroles). In such areas, soil gas surveys can complement established geophysical and geochemical exploration. We report CO2, 222Rn (Radon) and 220Rn (Thoron) emission data and ground temperatures from the Aluto volcanic complex in the Main Ethiopian Rift to improve understanding of tectonic and volcanic controls on the existing geothermal system. This suite of gas emission measurements allows us to identify major, deep‐rooted permeable structures with active fluid circulation and identify suitable drilling targets for geothermal production wells on Aluto. We show that significant differences in gas signatures (i.e., efflux and spatial pattern) can be used to identify predominantly volcanically and/or tectonically influenced compartments. Major gas emissions indicate significant fluid circulation at depth, which is typical for magmatic systems. Such high gas emissions have been observed in areas affected by major tectonic structures interacting with magmatic bodies at depth (tectono‐volcanic). Predominantly fault‐controlled sectors also show hydrothermal fluid circulation, but to a lower extent compared to tectono‐volcanic sectors. Within the Aluto volcanic complex geothermal production wells mainly target such fault‐controlled domains, whereas results of the study indicate strongest fluid circulation in tectono‐volcanic sectors. This result should be considered for the future exploration and development strategy of the site.Publisher PDFPeer reviewe
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