19 research outputs found

    The globalization of cultural eutrophication in the coastal ocean: causes and consequences

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    Coastal eutrophication caused by anthropogenic nutrient inputs is one of the greatest threats to the health of coastal estuarine and marine ecosystems worldwide. Globally, similar to 24% of the anthropogenic N released in coastal watersheds is estimated to reach coastal ecosystems. Seven contrasting coastal ecosystems subject to a range of riverine inputs of freshwater and nutrients are compared to better understand and manage this threat. The following are addressed: (i) impacts of anthropogenic nutrient inputs on ecosystem services; (ii) how ecosystem traits minimize or amplify these impacts; (iii) synergies among pressures (nutrient enrichment, over fishing, coastal development, and climate-driven pressures in particular); and (iv) management of nutrient inputs to coastal ecosystems. This comparative analysis shows that "trophic status," when defined in terms of the level of primary production, is not useful for relating anthropogenic nutrient loading to impacts. Ranked in terms of the impact of cultural eutrophication, Chesapeake Bay ranks number one followed by the Baltic Sea, Northern Adriatic Sea, Northern Gulf of Mexico, Santa Barbara Channel, East China Sea, and the Great Barrier Reef. The impacts of increases in anthropogenic nutrient loading (e.g., development of "dead zones," loss of biologically engineered habitats, and toxic phytoplankton events) are, and will continue to be, exacerbated by synergies with other pressures, including over fishing, coastal development and climate-driven increases in sea surface temperature, acidification and rainfall. With respect to management, reductions in point source inputs from sewage treatment plants are increasingly successful. However, controlling inputs from diffuse sources remains a challenging problem. The conclusion from this analysis is that the severity of coastal eutrophication will likely continue to increase in the absence of effectively enforced, ecosystem-based management of both point and diffuse sources of nitrogen and phosphorus. This requires sustained, integrated research and monitoring, as well as repeated assessments of nutrient loading and impacts. These must be informed and guided by ongoing collaborations among scientists, politicians, managers and the public.info:eu-repo/semantics/publishedVersio

    Diseases of the central nervous system caused by lymphocytic choriomeningitis virus and other arenaviruses

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    This chapter highlights the neurologic sequelae of viruses from two major groups of arenaviruses, the Lassa-lymphocytic choriomeningitis serocomplex and the Tacaribe serocomplex. Fundamental features of these viruses are reviewed, including the rich history of their discovery and the large influence that the study of arenaviruses has had on the disciplines of virology and immunology more generally. Virus morphology, viral genome organization, individual viral protein functions, and small-animal models of disease are also discussed. The epidemiology, natural history, and laboratory evaluation of the arenaviruses that cause human illness are presented. In particular, the neurologic complications of lymphocytic choriomeningitis virus in immunocompetent, pregnant, and solid-organ transplant patients are highlighted. The neurologic sequelae of the arenaviruses that cause hemorrhagic fever (i.e., Lassa fever, Argentine hemorrhagic fever, Bolivian hemorrhagic fever, Venezuelan hemorrhagic fever) are also presented. Lastly, potential treatment and vaccine strategies of these diseases are reviewed. © 2014 Elsevier B.V

    Use of quantitative ultrasound to assess bone status in children with juvenile idiopathic arthritis

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    Periarticular osteoporosis around inflamed joints and generalized osteoporosis have been shown to be markers of disease activity and severity in children with juvenile idiopathic arthritis (JIA). Bone mineral density (BMD) in adults can be assessed precisely by dual X-ray absorptiometry (DXA), but this technique has not been used widely in children. Quantitative ultrasound (QUS) may provide an alternative method for assessment of bone status. The aim of this pilot study was to compare QUS to DXA in assessing generalized osteoporosis in a cohort of patients with JIA. Twenty-two Caucasian children (15 females, 7 males) with JIA of duration of 19–142 (mean 71 mo) and age 7–17 yr were recruited. Total body and lumbar spine BMD and bone mineral content (BMC) were measured by DXA using standard procedures on a Lunar DPX-L scanner. QUS was performed using Myriad SoundScan 2000. Speed of sound (SOS) was measured at the right midtibia. The DXA results were compared to QUS using linear regression analysis. Spine and total body BMD measured by DXA correlated significantly with tibia SOS (spine: r = 0.57, p < 0.007; total body: r = 0.68, p < 0.001). Spine BMC was similarly related to SOS as BMD (r = 0.58, p < 0.007). Individual patient weight and height were strong predictors of BMD, but only moderate predictors of SOS. The mean spine BMD was lower in the JIA patients compared to the normal ranges (mean Z-score of -1.19). BMD Z-scores were negatively associated with duration of disease. Patients taking steroids were associated with lower Z-scores. In conclusion, SOS shows a significant correlation with BMD as measured by DXA, albeit with wide 95% confidence intervals in this small pilot study. QUS was also well tolerated and was technically easy to perform in these children. With the added advantage that it is free from radiation risk, further assessment of this potentially valuable tool for measuring bone status in children is warranted

    Event-Related Potentials and Psychological Theory

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    This chapter discusses event-related potentials (ERPs) and psychological theory. Correlational statements about the “relationship” between some psychological variable and an ERP component are of little inherent value. What is needed are clear experimental predictions, based on specific psychological theories. Changes in the amplitudes, latencies, or scalp distributions of ERP components must be predicted in such a manner that the confirmation or rejection of hypotheses would either strengthen or weaken the underlying psychological theories. A substantial amount of work in field is botanical in character. Investigators seem to be content to roam the fields of the ERP plucking new flowers and naming them. The identification of a novel species (or component) becomes a goal. Taxonomy becomes an end rather than a means. While this activity does have some value, its importance should not be exaggerated. At this stage of research it behooves to eschew botany and concentrate on attempts to understand the functional significance of those ERP components that have been identified

    Awake Proning as an Adjunctive Therapy for Refractory Hypoxemia in Non-Intubated Patients with COVID-19 Acute Respiratory Failure: Guidance from an International Group of Healthcare Workers

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    Non-intubated patients with acute respiratory failure due to COVID-19 could benefit from awake proning. Awake proning is an attractive intervention in settings with limited resources, as it comes with no additional costs. However, awake proning remains poorly used probably because of unfamiliarity and uncertainties regarding potential benefits and practical application. To summarize evidence for benefit and to develop a set of pragmatic recommendations for awake proning in patients with COVID-19 pneumonia, focusing on settings where resources are limited, international healthcare professionals from high and low- and middle-income countries (LMICs) with known expertise in awake proning were invited to contribute expert advice. A growing number of observational studies describe the effects of awake proning in patients with COVID-19 pneumonia in whom hypoxemia is refractory to simple measures of supplementary oxygen. Awake proning improves oxygenation in most patients, usually within minutes, and reduces dyspnea and work of breathing. The effects are maintained for up to 1 hour after turning back to supine, and mostly disappear after 6–12 hours. In available studies, awake proning was not associated with a reduction in the rate of intubation for invasive ventilation. Awake proning comes with little complications if properly implemented and monitored. Pragmatic recommendations including indications and contraindications were formulated and adjusted for resource-limited settings. Awake proning, an adjunctive treatment for hypoxemia refractory to supplemental oxygen, seems safe in non-intubated patients with COVID-19 acute respiratory failure. We provide pragmatic recommendations including indications and contraindications for the use of awake proning in LMICs

    Awake Proning as an Adjunctive Therapy for Refractory Hypoxemia in Non-Intubated Patients with COVID-19 Acute Respiratory Failure: Guidance from an International Group of Healthcare Workers

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    Non-intubated patients with acute respiratory failure due to COVID-19 could benefit from awake proning. Awake proning is an attractive intervention in settings with limited resources, as it comes with no additional costs. However, awake proning remains poorly used probably because of unfamiliarity and uncertainties regarding potential benefits and practical application. To summarize evidence for benefit and to develop a set of pragmatic recommendations for awake proning in patients with COVID-19 pneumonia, focusing on settings where resources are limited, international healthcare professionals from high and low- and middle-income countries (LMICs) with known expertise in awake proning were invited to contribute expert advice. Agrowing number of observational studies describe the effects of awake proning in patients with COVID-19 pneumonia in whom hypoxemia is refractory to simple measures of supplementary oxygen. Awake proning improves oxygenation in most patients, usually within minutes, and reduces dyspnea and work of breathing. The effects are maintained for up to 1 hour after turning back to supine, and mostly disappear after 6-12 hours. In available studies, awake proning was not associated with a reduction in the rate of intubation for invasive ventilation. Awake proning comes with little complications if properly implemented and monitored. Pragmatic recommendations including indications and contraindications were formulated and adjusted for resource-limited settings. Awake proning, an adjunctive treatment for hypoxemia refractory to supplemental oxygen, seems safe in non-intubated patients with COVID-19 acute respiratory failure. We provide pragmatic recommendations including indications and contraindications for the use of awake proning in LMICs
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