910 research outputs found
Progressive approach to eruption at Campi Flegrei caldera in southern Italy
Unrest at large calderas rarely ends in eruption, encouraging vulnerable communities to perceive emergency warnings of volcanic activity as false alarms. A classic example is the Campi Flegrei caldera in southern Italy, where three episodes of major uplift since 1950 have raised its central district by about 3 m without an eruption. Individual episodes have conventionally been treated as independent events, so that only data from an ongoing episode are considered pertinent to evaluating eruptive potential. An implicit assumption is that the crust relaxes accumulated stress after each episode. Here we apply a new model of elastic-brittle failure to test the alternative view that successive episodes promote a long-term accumulation of stress in the crust. The results provide the first quantitative evidence that Campi Flegrei is evolving towards conditions more favourable to eruption and identify field tests for predictions on how the caldera will behave during future unrest
Validation of the sperm class analyser CASA system for sperm counting in a busy diagnostic semen analysis laboratory
The type II RAF inhibitor tovorafenib in relapsed/refractory pediatric low-grade glioma: The phase 2 FIREFLY-1 trial
BRAF genomic alterations are the most common oncogenic drivers in pediatric low-grade glioma (pLGG). Arm 1 (n = 77) of the ongoing phase 2 FIREFLY-1 (PNOC026) trial investigated the efficacy of the oral, selective, central nervous system-penetrant, type II RAF inhibitor tovorafenib (420 mg
The challenges of long-term follow-up data collection in non-commercial, academically-led breast cancer clinical trials: the UK perspective
BACKGROUND: Improved survival rates in early breast cancer and the chronic nature of disease relapse result in a large cohort of patients being available for long-term follow-up (LTFUP) in randomised controlled trials. Whilst of recognised scientific value to assess long-term treatment-related sequelae, the volume of this activity can be challenging for trialists and participating sites, and comes at a considerable cost to research funders and the National Health Service (NHS). A National Cancer Research Institute Breast Clinical Studies Group supported project aimed to characterise UK LTFUP data collection procedures in order to propose improvements. METHODS: Protocols and case report forms for UK non-commercial National Institute for Health Research portfolio early breast cancer randomised controlled trials were reviewed and a questionnaire sent to associated participating NHS sites. Responders were asked to give opinions on issues with follow-up and LTFUP data collection procedures and to suggest potential improvements to practice. Results were used to inform design of a proposed standard LTFUP case report form. RESULTS: Thirty-four trials, involving eight Clinical Trials Units were eligible for inclusion in the review. All trials requested follow-up at least annually up to 5 years, with two-thirds requesting LTFUP after that time point. Information relating to efficacy endpoints was captured for all trials via case report forms; however, precise detail on recording of recurrence, second malignancies and death varied. Separately, questionnaires were returned from 66 NHS sites. Main concerns identified included difficulties in identifying all adverse events from hospital notes, volume of work, bureaucratic data management practices in Clinical Trials Units and perceptions of prioritisation of recruitment over follow-up. CONCLUSION: Variation has existed with respect to detail of LTFUP information requested for UK trials. Improved communication, simplification and standardisation of data and associated collection methods are possible without compromising data requirements for efficient and effective trial reporting. Future use of routinely collected data, captured via electronic means, could transform practices and alleviate resource usage. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1745-6215-15-379) contains supplementary material, which is available to authorized users
The blue suns of 1831: was the eruption of Ferdinandea, near Sicily, one of the largest volcanic climate forcing events of we nineteenth century?
One of the largest climate forcing eruptions of the nineteenth century was, until recently, believed to have taken place at the Babuyan Claro volcano, in the Philippines, in 1831. However, a recent investigation found no reliable evidence of such an eruption, suggesting that the 1831 eruption must have taken place elsewhere. We here present our newly compiled dataset of reported observations of a blue, purple and green sun in August 1831, which we use to reconstruct the transport of a stratospheric aerosol plume from that eruption. The source of the aerosol plume is identified as the eruption of Ferdinandea, which took place about 50 km off the south-west coast of Sicily (37.1∘ N, 12.7∘ E), in July and August 1831. The modest magnitude of this eruption, assigned a volcanic explosivity index (VEI) of 3, has commonly caused it to be discounted or overlooked when identifying the likely source of the stratospheric sulfate aerosol in 1831. It is proposed, however, that convective instability in the troposphere contributed to aerosol reaching the stratosphere and that the aerosol load was enhanced by addition of a sedimentary sulfur component to the volcanic plume. Thus, one of the largest climate forcing volcanic eruptions of the nineteenth century would effectively have been hiding in plain sight, arguably “lowering the bar” for the types of eruptions capable of having a substantial climate forcing impact. Prior estimates of the mass of stratospheric sulfate aerosol responsible for the 1831 Greenland ice core sulfate deposition peaks which have assumed a source eruption at a low-latitude site will, therefore, have been overstated. The example presented in this paper serves as a useful reminder that VEI values were not intended to be reliably correlated with eruption sulfur yields unless supplemented with compositional analyses. It also underlines that eye-witness accounts of historical geophysical events should not be neglected as a source of valuable scientific data
Short-term impacts of an unconditional cash transfer program on child schooling: Experimental evidence from Malawi.
This study analyzes the impact of a positive income shock on child schooling outcomes using experimental data from an unconditional cash transfer program in Malawi. Since households receive the cash and parents are responsible for making spending decisions, we also examine the intervening pathways between cash transfers and child schooling. Data comes from a cluster-randomized study of Malawi’s Social Cash Transfer Program (SCTP). After a baseline survey, households in village clusters were randomly assigned to treatment and control arms with treatment villages receiving transfers immediately and control villages assigned a later entry. We test for treatment impacts on a panel of school-aged children (6–17) using a differences-in-differences model. After a years’ worth of transfers, we find the Malawi SCTP both improves enrollment rates and decreases dropouts. The main intervening pathway between the program and schooling is education expenditures, suggesting that the cash improves the demand for education by reducing financial constraints
Randomised controlled trial of fish oil supplement to treat cancer cachexia
This is the protocol for a review and there is no abstract. The objectives are as follows: Our overall aim is to provide an overview of interventions for preventing falls in older people by summarising the evidence from multiple Cochrane intervention reviews that evaluate the effects (primarily, rate of falls and number of fallers) of these interventions in different populations of older people, such as those defined by setting or by specific medical conditions. Fall prevention interventions will include those in the following categories: supervised or unsupervised exercises; medication; surgery; management of urinary incontinence; fluid or nutrition therapy; psychological; environment and assistive technologies; social environment; knowledge/education interventions and any other interventions that do not fall into one of these categories (Lamb 2007). Interventions tested may belong to one category ('single' intervention), or more than one category ('multiple' and 'multifactorial' interventions)
Paying for Happiness: Experimental Results from a Large Cash Transfer Program in Malawi
This study analyzes the short-term impact of an exogenous, positive income shock on caregivers’ subjective well-being (SWB) in Malawi using panel data from 3,365 households targeted to receive Malawi’s Social Cash Transfer Program that provides unconditional cash to ultra-poor, labor-constrained households. The study consists of a cluster-randomized, longitudinal design. After the baseline survey, half of these village clusters were randomly selected to receive the transfer and a follow-up was conducted 17 months later. We find that the short-term impact of household income increases from the cash transfer leads to substantial SWB gains among caregivers. After a year’s worth of transfers, caregivers in beneficiary households have higher life satisfaction and are more likely to believe in a better future. We examine whether program impacts on consumption, food security, resilience, and hopefulness could explain the increase in SWB but do not find that any of these mechanisms individually mediate our results
Relationship between microstructures and grain-scale trace element distribution in komatiite-hosted magmatic sulphide ores
Komatiite-hosted nickel sulphides from the Yilgarn Craton (Australia) consist of two main sulphide phases: pyrrhotite (Fe7S8) and pentlandite ((Fe,Ni)9S8); two minor sulphide phases: chalcopyrite (CuFeS2) and pyrite (FeS2) and trace arsenides. Samples of massive sulphides from three deposits with diverse deformation and metamorphic histories (the Silver Swan, Perseverance and Flying Fox deposits) have been studied by electron backscatter diffraction and laser ablation inductively coupled plasma mass spectrometry and nano-scale secondary ion mass spectrometry. These ore bodies were selected to investigate the relationship between microstructures and mineral trace element chemistry in three dominant sulphide species in each deposit. In all three samples, pyrrhotite preserves a strong evidence of crystal plasticity relative to both pentlandite and pyrite. The trace element composition of pyrrhotite shows significant variation in specific elements (Pb, Bi and Ag). This variation correlates spatially with intragrain pyrrhotite microstructures, such as low angle and twin boundaries. Minor signatures of crystal plasticity in pyrite and pentlandite occur in the form of rare low angle boundaries (pentlandite) and mild lattice misorientation (pyrite). Trace element compositions of pentlandite and pyrite show no correlation with microstructures.Variations in pyrrhotite are interpreted as a result of intragrain diffusion during the syn- and post-deformation history of the deposit. Intragrain diffusion can occur either due to bulk diffusion, dislocation–impurity pair diffusion, or by “pipe diffusion”, i.e. along fast diffusion pathways at high and low angle, and twin boundaries. This contribution examines three different diffusion models and suggests that dislocation–impurity pair diffusion and pipe diffusion are the most likely processes behind increased trace element concentration along the microstructures in pyrrhotite. The same phenomenon is observed in samples from three different deposits that experienced widely different metamorphic conditions, implying that the final disposition of these elements reflects a post peak-metamorphic stage of the geological history of all three deposits
Literature searches and reviews related to the prevalence of food allergy in Europe
In 2011, the European Food Safety Authority (EFSA) received a mandate from the Food Safety Authority of Ireland (FSAI) to review the available scientific data on the prevalence of each food allergy in Europe, to derive threshold concentrations for each allergen in foods when possible, and to review the analytical methods available for the detection/quantification of food allergens. This report presents the findings of a series of systematic reviews of the literature related to these aims. Systematic searches of relevant bibliographic databases and the grey literature were conducted, studies were selected for inclusion according to pre-specified criteria, relevant data was extracted from all included studies, and the quality of included studies assessed. The first systematic review examined the literature on the prevalence of food allergy (IgE-mediated and non-IgE mediated) in different regions of the World and in individual European countries for different age groups in relation to each of the following food allergens: milk/dairy, eggs, cereals, peanuts, nuts, celery, crustaceans, fish, molluscs, soy, lupin, mustard and sesame. For each of these allergens changes in prevalence trends over time were also examined. Additionally, emerging food allergens in different European countries were identified. Of the 7333 articles identified by the searches, data from 92 studies was included, 52 of which reported on studies conducted within Europe. The second systematic review examined the effects of food processing on the allergenicity of foods in relation to each of the following food allergens: milk/dairy, eggs, cereals, peanuts, nuts, celery, crustaceans, fish, molluscs, soy, lupin, mustard and sesame. From 1040 articles identified by the searches, 25 studies were included in this review. The final systematic review examined the evidence regarding the new analytical methods available to analyse/detect the food allergens considered in the previous systematic reviews in processed foods. From 1475 articles identified by the searches, 84 studies were included
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