| 1. |
- Algaba, Juan-Carlos, et al.
(författare)
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Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign
- 2021
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Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 911:1
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Forskningsöversikt (refereegranskat)abstract
- In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M o˙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87's spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded.
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| 2. |
- Barnes, Paul W., et al.
(författare)
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Ozone depletion, ultraviolet radiation, climate change and prospects for a sustainable future
- 2019
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Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 2:7, s. 569-579
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Forskningsöversikt (refereegranskat)abstract
- © 2019, Springer Nature Limited. Changes in stratospheric ozone and climate over the past 40-plus years have altered the solar ultraviolet (UV) radiation conditions at the Earth’s surface. Ozone depletion has also contributed to climate change across the Southern Hemisphere. These changes are interacting in complex ways to affect human health, food and water security, and ecosystem services. Many adverse effects of high UV exposure have been avoided thanks to the Montreal Protocol with its Amendments and Adjustments, which have effectively controlled the production and use of ozone-depleting substances. This international treaty has also played an important role in mitigating climate change. Climate change is modifying UV exposure and affecting how people and ecosystems respond to UV; these effects will become more pronounced in the future. The interactions between stratospheric ozone, climate and UV radiation will therefore shift over time; however, the Montreal Protocol will continue to have far-reaching benefits for human well-being and environmental sustainability.
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| 3. |
- Hunsicker, Mary E., et al.
(författare)
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Functional responses and scaling in predator-prey interactions of marine fishes : contemporary issues and emerging concepts
- 2011
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Ingår i: Ecology Letters. - : Wiley-Blackwell. - 1461-023X .- 1461-0248. ; 14:12, s. 1288-1299
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Forskningsöversikt (refereegranskat)abstract
- Predatorprey interactions are a primary structuring force vital to the resilience of marine communities and sustainability of the worlds oceans. Human influences on marine ecosystems mediate changes in species interactions. This generality is evinced by the cascading effects of overharvesting top predators on the structure and function of marine ecosystems. It follows that ecological forecasting, ecosystem management, and marine spatial planning require a better understanding of food web relationships. Characterising and scaling predatorprey interactions for use in tactical and strategic tools (i.e. multi-species management and ecosystem models) are paramount in this effort. Here, we explore what issues are involved and must be considered to advance the use of predatorprey theory in the context of marine fisheries science. We address pertinent contemporary ecological issues including (1) the approaches and complexities of evaluating predator responses in marine systems; (2) the scaling up of predatorprey interactions to the population, community, and ecosystem level; (3) the role of predatorprey theory in contemporary fisheries and ecosystem modelling approaches; and (4) directions for the future. Our intent is to point out needed research directions that will improve our understanding of predatorprey interactions in the context of the sustainable marine fisheries and ecosystem management.
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| 6. |
- Saunders, Charlie N., et al.
(författare)
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Lack of association between modifiable exposures and glioma risk : a Mendelian randomization analysis
- 2020
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Ingår i: Neuro-Oncology. - : OXFORD UNIV PRESS INC. - 1522-8517 .- 1523-5866. ; 22:2, s. 207-215
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Forskningsöversikt (refereegranskat)abstract
- Background. The etiological basis of glioma is poorly understood. We have used genetic markers in a Mendelian randomization (MR) framework to examine if lifestyle, cardiometabolic, and inflammatory factors influence the risk of glioma. This methodology reduces bias from confounding and is not affected by reverse causation. Methods. We identified genetic instruments for 37 potentially modifiable risk factors and evaluated their association with glioma risk using data from a genome-wide association study of 12488 glioma patients and 18169 controls. We used the estimated odds ratio of glioma associated with each of the genetically defined traits to infer evidence for a causal relationship with the following exposures: Lifestyle and dietary factors-height, plasma insulin-like growth factor 1, blood carnitine, blood methionine, blood selenium, blood zinc, circulating adiponectin, circulating carotenoids, iron status, serum calcium, vitamins (A1, B12, B6, E, and 25-hydroxyvitamin D), fatty acid levels (monounsaturated, omega-3, and omega-6) and circulating fetuin-A; Cardiometabolic factors-birth weight, high density lipoprotein cholesterol, low density lipoprotein cholesterol, total cholesterol, total triglycerides, basal metabolic rate, body fat percentage, body mass index, fasting glucose, fasting proinsulin, glycated hemoglobin levels, diastolic and systolic blood pressure, waist circumference, waist-to-hip ratio; and Inflammatory factors- C-reactive protein, plasma interleukin-6 receptor subunit alpha and serum immunoglobulin E. Results. After correction for the testing of multiple potential risk factors and excluding associations driven by one single nucleotide polymorphism, no significant association with glioma risk was observed (ie, P-Corrected > 0.05). Conclusions. This study did not provide evidence supporting any of the 37 factors examined as having a significant influence on glioma risk.
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| 7. |
- Pignolo, Robert J., et al.
(författare)
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The effects of palovarotene in patients with fibrodysplasia ossificans progressiva : a plain language summary
- 2023
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Ingår i: Future Rare Diseases. - : Future Medicine. - 2399-5270 .- 2399-5262. ; 3:1
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Forskningsöversikt (refereegranskat)abstract
- What is this summary about?This is a plain language summary of an article originally published in the Journal of Bone and Mineral Research. People with fibrodysplasia ossificans progressiva (FOP) become physically disabled over time as new bone forms in places where it is not usually found, such as in muscles and ligaments. Until recently, there were no treatments for FOP that had been proven through clinical trials; however, a drug called palovarotene has been tested in clinical trials and may be effective. Here, we describe the MOVE trial, which investigated how effectively palovarotene works, as well as its safety in treating patients with FOP.What were the results?Results from MOVE suggest that palovarotene may reduce extra bone formation outside the normal skeleton. Patients with FOP who took palovarotene formed less new bone than those who did not take palovarotene. The most common side effects involved the skin, and included dryness and irritation. Some children who were still growing when they took palovarotene had a side effect that resulted in the (normal) growth of their skeleton stopping too soon.What do the results of the trial mean?Palovarotene may be a useful treatment option for FOP. Patients, caregivers, and doctors would need to consider the benefits and risks of treatment with palovarotene, particularly with growing children.
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| 8. |
- Sutton, Richard, et al.
(författare)
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Tilt testing remains a valuable asset
- 2021
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Ingår i: European Heart Journal. - : Oxford University Press (OUP). - 1522-9645 .- 0195-668X.
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Forskningsöversikt (refereegranskat)abstract
- Head-up tilt test (TT) has been used for >50 years to study heart rate/blood pressure adaptation to positional changes, to model responses to haemorrhage, to assess orthostatic hypotension, and to evaluate haemodynamic and neuroendocrine responses in congestive heart failure, autonomic dysfunction, and hypertension. During these studies, some subjects experienced syncope due to vasovagal reflex. As a result, tilt testing was incorporated into clinical assessment of syncope when the origin was unknown. Subsequently, clinical experience supports the diagnostic value of TT. This is highlighted in evidence-based professional practice guidelines, which provide advice for TT methodology and interpretation, while concurrently identifying its limitations. Thus, TT remains a valuable clinical asset, one that has added importantly to the appreciation of pathophysiology of syncope/collapse and, thereby, has improved care of syncopal patients.
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| 9. |
- van den Berg, Martin, et al.
(författare)
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Polybrominated Dibenzo-p-Dioxins, Dibenzofurans, and Biphenyls : Inclusion in the Toxicity Equivalency Factor Concept for Dioxin-Like Compounds
- 2013
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Ingår i: Toxicological Sciences. - Oxfors, United Kingdom : Oxford University Press. - 1096-6080 .- 1096-0929. ; 133:2, s. 197-208
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Forskningsöversikt (refereegranskat)abstract
- In 2011 a joint World Health Organization (WHO) and United Nations Environment Programme (UNEP) expert consultation took place, during which the possible inclusion of brominated analogues of the dioxin-like compounds in the WHO Toxicity Equivalency Factor (TEF) scheme were evaluated. The expert panel concluded that polybrominated dibenzo-p-dioxins (PBDDs), dibenzofurans (PBDFs), and some dioxin-like biphenyls (dl-PBBs) may contribute significantly in daily human background exposure to the total dioxin toxic equivalencies (TEQs). These compounds are also commonly found in the aquatic environment. Available data for fish toxicity were evaluated for possible inclusion in the WHO-UNEP TEF scheme (Van den Berg et al., 1998). Because of the limited database it was decided not to derive specific WHO-UNEP TEFs for fish, but for ecotoxicological risk assessment the use of specific relative effect potencies (REPs) from fish embryo assays is recommended. Based on the limited mammalian REP database for these brominated compounds, it was concluded that sufficient differentiation from the present TEF values of the chlorinated analogues (Van den Berg et al., 2005) was not possible. However, the REPs for PBDDs, PBDFs, and non-ortho dl-PBBs in mammals closely follow those of the chlorinated analogues, at least within one order of magnitude. Therefore, the use of similar interim TEF values for brominated and chlorinated congeners for human risk assessment is recommended, pending more detailed information in the future.
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