126 research outputs found

    High-Precision Mass-Dependent Molybdenum Isotope Variations in Magmatic Rocks Determined by Double-Spike MC-ICP-MS

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    Small mass‐dependent variations of molybdenum isotope ratios in oceanic and island arc rocks are expected as a result of recycling altered oceanic crust and sediments into the mantle at convergent plate margins over geological timescales. However, the determination of molybdenum isotope data precise and accurate enough to identify these subtle isotopic differences remains challenging. Large sample sizes – in excess of 200 mg – need to be chemically processed to isolate enough molybdenum in order to allow sufficiently high‐precision isotope analyses using double‐spike MC‐ICP‐MS techniques. Established methods are either unable to process such large amounts of silicate material or require several distinct chemical processing steps, making the analyses very time‐consuming. Here, we present a new and efficient single‐pass chromatographic exchange technique for the chemical isolation of molybdenum from silicate and metal matrices. To test our new method, we analysed USGS reference materials BHVO‐2 and BIR‐1. Our new data are consistent with those derived from more involved and time‐consuming methods for these two reference materials previously published. We also provide the first molybdenum isotope data for USGS reference materials AGV‐2, the GSJ reference material JB‐2 as well as metal NIST SRM 361.ISSN:1639-4488ISSN:1751-908

    Abundances and Physical Conditions in the Warm Neutral Medium Towards mu Columbae

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    We present ultraviolet interstellar absorption line measurements for the sightline towards the O9.5 V star mu Columbae obtained with the Goddard High Resolution Spectrograph (GHRS) on board the Hubble Space Telescope. These archival data represent the most complete GHRS interstellar absorption line measurements for any line of sight towards an early-type star. The 3.5 km/s resolution of the instrument allow us to accurately derive the gas-phase column densities of many important ionic species in the diffuse warm neutral medium using a combination of apparent column density and component fitting techniques, and we study in detail the contamination from ionized gas along this sightline. The low-velocity material shows gas-phase abundance patterns similar to the warm cloud (cloud A) towards the disk star zeta Oph, while the component at v = +20.1 km/s shows gas-phase abundances similar to those found in warm halo clouds. We find the velocity-integrated gas-phase abundances of Zn, P, and S relative to H along this sightline are indistinguishable from solar system abundances. We discuss the implications of our gas-phase abundance measurements for the composition of interstellar dust. The relative ionic column density ratios of the intermediate velocity components show the imprint both of elemental incorporation into grains and (photo)ionization. The components at v = -30 and -48 km/s along this sightline likely trace shocked gas with very low hydrogen column densities. Appendices include a new derivation of the GHRS instrumental line spread function, and a new very accurate determination of the total H I column along this sightline. (Abridged)Comment: Accepted for publication in the Astrophysical Journal. 80 pages including 19 embedded figures and 12 embedded tables. Version with higher resolution figures can be downloaded from http://fuse.pha.jhu.edu/~howk/Papers/papers.htm

    Exploring the putative interactions between chronic kidney disease and chronic periodontitis.

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    Chronic kidney disease (CKD) and chronic periodontitis (CP) are both common diseases, which are found disproportionately comorbid with each other and have been reported to have a detrimental effect on the progression of each respective disease. They have an overlap in risk factors and both are a source of systemic inflammation along with a wide selection of immunological and non-specific effects that can affect the body over the lifespan of the conditions. Previous studies have investigated the directionality of the relationship between these two diseases; however, there is a lack of literature that has examined how these diseases may be interacting at the localized and systemic level. This review discusses how oral microorganisms have the ability to translocate and have distal effects and provides evidence for microbial involvement in a systemic disease. Furthermore, it summarizes the reported local and systemic effects of CKD and CP and discusses how the interaction of these effects may be responsible for directionality associations reported

    Longitudinal clinical study of patients with iron rim lesions in multiple sclerosis

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    Background: Iron rims (IRs) surrounding white matter lesions (WMLs) are suggested to predict a more severe disease course. Only small longitudinal cohorts of patients with and without iron rim lesions (IRLs) have been reported so far. Objective: To assess whether the presence and number of IRLs in patients with clinically isolated syndrome (CIS) and multiple sclerosis (MS) are associated with long-term disability or progressive disease. Methods: Ninety-one CIS/MS patients were recruited between 2008 and 2013 and scanned with 7 T magnetic resonance imaging (MRI). Expanded Disability Status Scale (EDSS) was used to calculate Age-related Multiple Sclerosis Severity Score (ARMSS) at the time of scan and at the latest clinical follow-up after 9 years. WMLs were assessed for the presence of IRL using Susceptibility weighted imaging (SWI)-filtered phase images. Results: In all, 132 IRLs were detected in 42 patients (46%); 9% of WMLs had IRs; 54% of the cohort had no rims, 30% had 1–3 rims and 16% had ⩾4. Patients with IRL had a higher EDSS and ARMSS. Presence of IRL was also a predictor of long-term disability, especially in patients with ⩾4 IRLs. IRLs have a greater impact on disability compared to the WML number and volume. Conclusion: The presence and number of perilesional IR on MRI hold prognostic value for long-term clinical disability in MS

    Towards comprehensive observing and modeling systems for monitoring and predicting regional to coastal sea level

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    A major challenge for managing impacts and implementing effective mitigation measures and adaptation strategies for coastal zones affected by future sea level (SL) rise is our limited capacity to predict SL change at the coast on relevant spatial and temporal scales. Predicting coastal SL requires the ability to monitor and simulate a multitude of physical processes affecting SL, from local effects of wind waves and river runoff to remote influences of the large-scale ocean circulation on the coast. Here we assess our current understanding of the causes of coastal SL variability on monthly to multi-decadal timescales, including geodetic, oceanographic and atmospheric aspects of the problem, and review available observing systems informing on coastal SL. We also review the ability of existing models and data assimilation systems to estimate coastal SL variations and of atmosphere-ocean global coupled models and related regional downscaling efforts to project future SL changes. We discuss (1) observational gaps and uncertainties, and priorities for the development of an optimal and integrated coastal SL observing system, (2) strategies for advancing model capabilities in forecasting short-term processes and projecting long-term changes affecting coastal SL, and (3) possible future developments of sea level services enabling better connection of scientists and user communities and facilitating assessment and decision making for adaptation to future coastal SL change.RP was funded by NASA grant NNH16CT00C. CD was supported by the Australian Research Council (FT130101532 and DP 160103130), the Scientific Committee on Oceanic Research (SCOR) Working Group 148, funded by national SCOR committees and a grant to SCOR from the U.S. National Science Foundation (Grant OCE-1546580), and the Intergovernmental Oceanographic Commission of UNESCO/International Oceanographic Data and Information Exchange (IOC/IODE) IQuOD Steering Group. SJ was supported by the Natural Environmental Research Council under Grant Agreement No. NE/P01517/1 and by the EPSRC NEWTON Fund Sustainable Deltas Programme, Grant Number EP/R024537/1. RvdW received funding from NWO, Grant 866.13.001. WH was supported by NASA (NNX17AI63G and NNX17AH25G). CL was supported by NASA Grant NNH16CT01C. This work is a contribution to the PIRATE project funded by CNES (to TP). PT was supported by the NOAA Research Global Ocean Monitoring and Observing Program through its sponsorship of UHSLC (NA16NMF4320058). JS was supported by EU contract 730030 (call H2020-EO-2016, “CEASELESS”). JW was supported by EU Horizon 2020 Grant 633211, Atlantos

    Researching the mental health needs of hard-to-reach groups: managing multiple sources of evidence

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    Background: common mental health problems impose substantial challenges to patients, carers, and health care systems. A range of interventions have demonstrable efficacy in improving the lives of people experiencing such problems. However many people are disadvantaged, either because they are unable to access primary care, or because access does not lead to adequate help. New methods are needed to understand the problems of access and generate solutions. In this paper we describe our methodological approach to managing multiple and diverse sources of evidence, within a research programme to increase equity of access to high quality mental health services in primary care.Methods: we began with a scoping review to identify the range and extent of relevant published material, and establish key concepts related to access. We then devised a strategy to collect - in parallel - evidence from six separate sources: a systematic review of published quantitative data on access-related studies; a meta-synthesis of published qualitative data on patient perspectives; dialogues with local stakeholders; a review of grey literature from statutory and voluntary service providers; secondary analysis of patient transcripts from previous qualitative studies; and primary data from interviews with service users and carers.We synthesised the findings from these diverse sources, made judgements on key emerging issues in relation to needs and services, and proposed a range of potential interventions. These proposals were debated and refined using iterative electronic and focus group consultation procedures involving international experts, local stakeholders and service users.Conclusions: our methods break new ground by generating and synthesising multiple sources of evidence, connecting scientific understanding with the perspectives of users, in order to develop innovative ways to meet the mental health needs of under-served group

    Socio-oceanography: an opportunity to integrate marine social and natural sciences

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    Marine natural sciences have been instrumental in helping society understand how ocean systems operate and the threats they face. However, there is a growing realisation that the societal challenges related to the marine environment can only be addressed through more effective integration with all aspects of social sciences. Nevertheless, to date, social sciences remain insufficiently integrated into marine research. Recognising historical weaknesses and drawing on the authors’ own experience of interdisciplinary research, albeit writing primarily from a natural marine science perspective, we propose a series of steps to promote integrated marine research inclusive of strong social science. We suggest that changing the perspectives and attitudes of natural scientists is key. The inherent interconnectivity between the ocean and society ensures that nearly everything we do in the marine natural sciences has the potential to influence and, perhaps address, ongoing and future societal challenges. Consequently, a key challenge for natural scientists is to recognise and communicate this in an accessible manner outside their own disciplines. To attempt to address these issues, we introduce the concept of “Socio-oceanography” which we define as an area of research that takes a “whole system” approach to the marine environment. It focuses on the challenges which require advancement of both natural and social science components, especially on those where the feedbacks between social and natural components are beginning to emerge. Here, we discuss its scope, challenges to its effective application and key steps to catalyse interdisciplinary approaches using this concept

    Os mártires e a cristianização do território na América portuguesa, séculos XVI e XVII

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    O artigo investiga um grupo de atores sociais bastante relevante para viabilizar a cristianização na América portuguesa: os mártires cristãos, indivíduos muito especiais, dispostos a regar a terra com seu próprio sangue, de forma a tornar definitiva e irreversível a ocupação cristã do território. Os mártires - e principalmente a narrativa em torno deles - parecem ter sido bastante acionados para integrar a América portuguesa e seus habitantes nativos à temporalidade e territorialidade cristã. Os mártires dos séculos XVI e XVII, principalmente missionários, reeditavam os martírios do início da cristandade, que espalharam o cristianismo rumo a diversas partes do mundo na antiguidade. Dessa forma, viabilizaram a cristianização das novas fronteiras, consagrando o solo com seu sangue divino e viabilizando posteriores processos de urbanização. Além da função estratégica dos mártires para os cristãos, o texto mostra que eles também tiveram significado peculiar na interlocução com as culturas ameríndias, que tinha como um de seus principais personagens o grande guerreiro, disposto a perder seu sangue em prol de seu grupo.This paper looks into a group of social agents who played a significant role in the Christianization of Portuguese America, namely, the Christian martyrs - very special individuals who were ready to wet the land with their own blood in order to make possible a definitive and irreversible occupation of the territory by Christian settlers. The martyrs, and above all the stories told about them, seem to have been called upon to integrate Portuguese America and its native inhabitants into the temporalities and territory of Christendom. Mostly made up of missionaries, this group of 16th and 17th-century martyrs reedited the martyrdom of early Christians, who spread their creed across numerous parts of the Ancient World. They enabled the Christianization of new frontiers by consecrating the soil with their divine blood and paving the way for subsequent processes of urban development. In addition to their strategic significance for Christianity, the text also shows that their martyrdom played a specific role in the Christian settlers' interaction with Amerindian culture, whose main cults included the figure of the great warrior, ever ready to shed his own blood for his group

    Quality of Health Care for Children in Australia, 2012-2013.

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    Importance: The quality of routine care for children is rarely assessed, and then usually in single settings or for single clinical conditions. Objective: To estimate the quality of health care for children in Australia in inpatient and ambulatory health care settings. Design, Setting, and Participants: Multistage stratified sample with medical record review to assess adherence with quality indicators extracted from clinical practice guidelines for 17 common, high-burden clinical conditions (noncommunicable [n = 5], mental health [n = 4], acute infection [n = 7], and injury [n = 1]), such as asthma, attention-deficit/hyperactivity disorder, tonsillitis, and head injury. For these 17 conditions, 479 quality indicators were identified, with the number varying by condition, ranging from 9 for eczema to 54 for head injury. Four hundred medical records were targeted for sampling for each of 15 conditions while 267 records were targeted for anxiety and 133 for depression. Within each selected medical record, all visits for the 17 targeted conditions were identified, and separate quality assessments made for each. Care was evaluated for 6689 children 15 years of age and younger who had 15 240 visits to emergency departments, for inpatient admissions, or to pediatricians and general practitioners in selected urban and rural locations in 3 Australian states. These visits generated 160 202 quality indicator assessments. Exposures: Quality indicators were identified through a systematic search of local and international guidelines. Individual indicators were extracted from guidelines and assessed using a 2-stage Delphi process. Main Outcomes and Measures: Quality of care for each clinical condition and overall. Results: Of 6689 children with surveyed medical records, 53.6% were aged 0 to 4 years and 55.5% were male. Adherence to quality of care indicators was estimated at 59.8% (95% CI, 57.5%-62.0%; n = 160 202) across the 17 conditions, ranging from a high of 88.8% (95% CI, 83.0%-93.1%; n = 2638) for autism to a low of 43.5% (95% CI, 36.8%-50.4%; n = 2354) for tonsillitis. The mean adherence by condition category was estimated as 60.5% (95% CI, 57.2%-63.8%; n = 41 265) for noncommunicable conditions (range, 52.8%-75.8%); 82.4% (95% CI, 79.0%-85.5%; n = 14 622) for mental health conditions (range, 71.5%-88.8%); 56.3% (95% CI, 53.2%-59.4%; n = 94 037) for acute infections (range, 43.5%-69.8%); and 78.3% (95% CI, 75.1%-81.2%; n = 10 278) for injury. Conclusions and Relevance: Among a sample of children receiving care in Australia in 2012-2013, the overall prevalence of adherence to quality of care indicators for important conditions was not high. For many of these conditions, the quality of care may be inadequate
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