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| 6. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: The European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6052. ; 75:9
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Tidskriftsartikel (refereegranskat)
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| 7. |
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| 10. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Journal of High Energy Physics. - : Springer. - 1029-8479 .- 1126-6708. ; :12
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Tidskriftsartikel (refereegranskat)
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| 11. |
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| 12. |
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| 13. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Journal of High Energy Physics. - : Societa Italiana di Fisica. - 1029-8479 .- 1126-6708. ; :9
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Tidskriftsartikel (refereegranskat)
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| 14. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368 .- 1550-7998. ; 92:9
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Tidskriftsartikel (refereegranskat)
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| 15. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 115:13
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Tidskriftsartikel (refereegranskat)
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| 16. |
- Aad, G., et al.
(författare)
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- 2015
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Tidskriftsartikel (refereegranskat)
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| 17. |
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| 18. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Journal of High Energy Physics. - : Societa Italiana di Fisica. - 1029-8479 .- 1126-6708. ; :8
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Tidskriftsartikel (refereegranskat)
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| 19. |
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| 20. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: The European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6052. ; 75:7
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Tidskriftsartikel (refereegranskat)
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| 21. |
- Aad, G., et al.
(författare)
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- 2015
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Tidskriftsartikel (refereegranskat)
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| 22. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Journal of High Energy Physics. - : Springer-Verlag New York. - 1029-8479 .- 1126-6708. ; :9
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Tidskriftsartikel (refereegranskat)
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| 23. |
- Aad, G., et al.
(författare)
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- 2015
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Tidskriftsartikel (refereegranskat)
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| 24. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review Letters. - : American Physical Society. - 1079-7114 .- 0031-9007. ; 114:22
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Tidskriftsartikel (refereegranskat)
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| 25. |
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| 26. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: The European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6052. ; 75:7
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Tidskriftsartikel (refereegranskat)
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| 27. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368 .- 1550-7998. ; 92:1
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Tidskriftsartikel (refereegranskat)
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| 28. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review Letters. - : American Physical Society. - 1079-7114 .- 0031-9007. ; 114:23
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Tidskriftsartikel (refereegranskat)
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| 29. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 115:3
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Tidskriftsartikel (refereegranskat)
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| 30. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813 .- 1089-490X. ; 92:3
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Tidskriftsartikel (refereegranskat)
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| 31. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368 .- 1550-7998. ; 91:11, s. 112011-
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Tidskriftsartikel (refereegranskat)
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| 32. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 115:9
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Tidskriftsartikel (refereegranskat)
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| 33. |
- Aad, G., et al.
(författare)
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- 2015
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Tidskriftsartikel (refereegranskat)
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| 34. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; :8
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Tidskriftsartikel (refereegranskat)
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| 35. |
- Aad, G., et al.
(författare)
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- 2015
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Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 115:3
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Tidskriftsartikel (refereegranskat)
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| 36. |
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| 37. |
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| 38. |
- 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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| 39. |
- Adams, C. B., et al.
(författare)
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Observation of the Gamma-Ray Binary HESS J0632+057 with the HESS, MAGIC, and VERITAS Telescopes
- 2021
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Ingår i: Astrophysical Journal. - : Institute of Physics Publishing (IOPP). - 0004-637X .- 1538-4357. ; 923:2
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Tidskriftsartikel (refereegranskat)abstract
- The results of gamma-ray observations of the binary system HESS J0632 + 057 collected during 450 hr over 15 yr, between 2004 and 2019, are presented. Data taken with the atmospheric Cherenkov telescopes H.E.S.S., MAGIC, and VERITAS at energies above 350 GeV were used together with observations at X-ray energies obtained with Swift-XRT, Chandra, XMM-Newton, NuSTAR, and Suzaku. Some of these observations were accompanied by measurements of the H alpha emission line. A significant detection of the modulation of the very high-energy gamma-ray fluxes with a period of 316.7 +/- 4.4 days is reported, consistent with the period of 317.3 +/- 0.7 days obtained with a refined analysis of X-ray data. The analysis of data from four orbital cycles with dense observational coverage reveals short-timescale variability, with flux-decay timescales of less than 20 days at very high energies. Flux variations observed over a timescale of several years indicate orbit-to-orbit variability. The analysis confirms the previously reported correlation of X-ray and gamma-ray emission from the system at very high significance, but cannot find any correlation of optical H alpha parameters with fluxes at X-ray or gamma-ray energies in simultaneous observations. The key finding is that the emission of HESS J0632 + 057 in the X-ray and gamma-ray energy bands is highly variable on different timescales. The ratio of gamma-ray to X-ray flux shows the equality or even dominance of the gamma-ray energy range. This wealth of new data is interpreted taking into account the insufficient knowledge of the ephemeris of the system, and discussed in the context of results reported on other gamma-ray binary systems.
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| 40. |
- Arndt, D. S., et al.
(författare)
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State of the Climate in 2016
- 2017
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Ingår i: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 98:8, s. S1-S280
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Tidskriftsartikel (refereegranskat)abstract
- In 2016, the dominant greenhouse gases released into Earth's atmosphere-carbon dioxide, methane, and nitrous oxide-continued to increase and reach new record highs. The 3.5 +/- 0.1 ppm rise in global annual mean carbon dioxide from 2015 to 2016 was the largest annual increase observed in the 58-year measurement record. The annual global average carbon dioxide concentration at Earth's surface surpassed 400 ppm (402.9 +/- 0.1 ppm) for the first time in the modern atmospheric measurement record and in ice core records dating back as far as 800000 years. One of the strongest El Nino events since at least 1950 dissipated in spring, and a weak La Nina evolved later in the year. Owing at least in part to the combination of El Nino conditions early in the year and a long-term upward trend, Earth's surface observed record warmth for a third consecutive year, albeit by a much slimmer margin than by which that record was set in 2015. Above Earth's surface, the annual lower troposphere temperature was record high according to all datasets analyzed, while the lower stratospheric temperature was record low according to most of the in situ and satellite datasets. Several countries, including Mexico and India, reported record high annual temperatures while many others observed near-record highs. A week-long heat wave at the end of April over the northern and eastern Indian peninsula, with temperatures surpassing 44 degrees C, contributed to a water crisis for 330 million people and to 300 fatalities. In the Arctic the 2016 land surface temperature was 2.0 degrees C above the 1981-2010 average, breaking the previous record of 2007, 2011, and 2015 by 0.8 degrees C, representing a 3.5 degrees C increase since the record began in 1900. The increasing temperatures have led to decreasing Arctic sea ice extent and thickness. On 24 March, the sea ice extent at the end of the growth season saw its lowest maximum in the 37-year satellite record, tying with 2015 at 7.2% below the 1981-2010 average. The September 2016 Arctic sea ice minimum extent tied with 2007 for the second lowest value on record, 33% lower than the 1981-2010 average. Arctic sea ice cover remains relatively young and thin, making it vulnerable to continued extensive melt. The mass of the Greenland Ice Sheet, which has the capacity to contribute similar to 7 m to sea level rise, reached a record low value. The onset of its surface melt was the second earliest, after 2012, in the 37-year satellite record. Sea surface temperature was record high at the global scale, surpassing the previous record of 2015 by about 0.01 degrees C. The global sea surface temperature trend for the 21st century-to-date of +0.162 degrees C decade(-1) is much higher than the longer term 1950-2016 trend of +0.100 degrees C decade(-1). Global annual mean sea level also reached a new record high, marking the sixth consecutive year of increase. Global annual ocean heat content saw a slight drop compared to the record high in 2015. Alpine glacier retreat continued around the globe, and preliminary data indicate that 2016 is the 37th consecutive year of negative annual mass balance. Across the Northern Hemisphere, snow cover for each month from February to June was among its four least extensive in the 47-year satellite record. Continuing a pattern below the surface, record high temperatures at 20-m depth were measured at all permafrost observatories on the North Slope of Alaska and at the Canadian observatory on northernmost Ellesmere Island. In the Antarctic, record low monthly surface pressures were broken at many stations, with the southern annular mode setting record high index values in March and June. Monthly high surface pressure records for August and November were set at several stations. During this period, record low daily and monthly sea ice extents were observed, with the November mean sea ice extent more than 5 standard deviations below the 1981-2010 average. These record low sea ice values contrast sharply with the record high values observed during 2012-14. Over the region, springtime Antarctic stratospheric ozone depletion was less severe relative to the 1991-2006 average, but ozone levels were still low compared to pre-1990 levels. Closer to the equator, 93 named tropical storms were observed during 2016, above the 1981-2010 average of 82, but fewer than the 101 storms recorded in 2015. Three basins-the North Atlantic, and eastern and western North Pacific-experienced above-normal activity in 2016. The Australian basin recorded its least active season since the beginning of the satellite era in 1970. Overall, four tropical cyclones reached the Saffir-Simpson category 5 intensity level. The strong El Nino at the beginning of the year that transitioned to a weak La Nina contributed to enhanced precipitation variability around the world. Wet conditions were observed throughout the year across southern South America, causing repeated heavy flooding in Argentina, Paraguay, and Uruguay. Wetter-than-usual conditions were also observed for eastern Europe and central Asia, alleviating the drought conditions of 2014 and 2015 in southern Russia. In the United States, California had its first wetter-than-average year since 2012, after being plagued by drought for several years. Even so, the area covered by drought in 2016 at the global scale was among the largest in the post-1950 record. For each month, at least 12% of land surfaces experienced severe drought conditions or worse, the longest such stretch in the record. In northeastern Brazil, drought conditions were observed for the fifth consecutive year, making this the longest drought on record in the region. Dry conditions were also observed in western Bolivia and Peru; it was Bolivia's worst drought in the past 25 years. In May, with abnormally warm and dry conditions already prevailing over western Canada for about a year, the human-induced Fort McMurray wildfire burned nearly 590000 hectares and became the costliest disaster in Canadian history, with $3 billion (U.S. dollars) in insured losses.
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| 41. |
- Arndt, D. S., et al.
(författare)
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STATE OF THE CLIMATE IN 2017
- 2018
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Ingår i: Bulletin of The American Meteorological Society - (BAMS). - : American Meteorological Society. - 0003-0007 .- 1520-0477. ; 99:8, s. S1-S310
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Forskningsöversikt (refereegranskat)
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| 42. |
- Menkveld, Albert J., et al.
(författare)
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Nonstandard Errors
- 2024
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Ingår i: JOURNAL OF FINANCE. - : Wiley-Blackwell. - 0022-1082 .- 1540-6261. ; 79:3, s. 2339-2390
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Tidskriftsartikel (refereegranskat)abstract
- In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty-nonstandard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for more reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants.
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| 43. |
- Kehoe, Laura, et al.
(författare)
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Make EU trade with Brazil sustainable
- 2019
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 364:6438, s. 341-
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 44. |
- Bousquet, Jean, et al.
(författare)
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ARIA digital anamorphosis : Digital transformation of health and care in airway diseases from research to practice
- 2021
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Ingår i: Allergy. European Journal of Allergy and Clinical Immunology. - : John Wiley & Sons. - 0105-4538 .- 1398-9995. ; 76:1, s. 168-190
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Forskningsöversikt (refereegranskat)abstract
- Digital anamorphosis is used to define a distorted image of health and care that may be viewed correctly using digital tools and strategies. MASK digital anamorphosis represents the process used by MASK to develop the digital transformation of health and care in rhinitis. It strengthens the ARIA change management strategy in the prevention and management of airway disease. The MASK strategy is based on validated digital tools. Using the MASK digital tool and the CARAT online enhanced clinical framework, solutions for practical steps of digital enhancement of care are proposed.
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| 45. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 46. |
- Bousquet, J. Jean, et al.
(författare)
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Next-generation ARIA care pathways for rhinitis and asthma : a model for multimorbid chronic diseases
- 2019
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Ingår i: Clinical and Translational Allergy. - : BMC. - 2045-7022. ; 9
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Forskningsöversikt (refereegranskat)abstract
- Background: In all societies, the burden and cost of allergic and chronic respiratory diseases are increasing rapidly. Most economies are struggling to deliver modern health care effectively. There is a need to support the transformation of the health care system into integrated care with organizational health literacy.Main body: As an example for chronic disease care, MASK (Mobile Airways Sentinel NetworK), a new project of the ARIA (Allergic Rhinitis and its Impact on Asthma) initiative, and POLLAR (Impact of Air POLLution on Asthma and Rhinitis, EIT Health), in collaboration with professional and patient organizations in the field of allergy and airway diseases, are proposing real-life ICPs centred around the patient with rhinitis, and using mHealth to monitor environmental exposure. Three aspects of care pathways are being developed: (i) Patient participation, health literacy and self-care through technology-assisted "patient activation", (ii) Implementation of care pathways by pharmacists and (iii) Next-generation guidelines assessing the recommendations of GRADE guidelines in rhinitis and asthma using real-world evidence (RWE) obtained through mobile technology. The EU and global political agendas are of great importance in supporting the digital transformation of health and care, and MASK has been recognized by DG Sante as a Good Practice in the field of digitally-enabled, integrated, person-centred care.Conclusion: In 20 years, ARIA has considerably evolved from the first multimorbidity guideline in respiratory diseases to the digital transformation of health and care with a strong political involvement.
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| 47. |
- Falster, Daniel, et al.
(författare)
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AusTraits, a curated plant trait database for the Australian flora
- 2021
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Ingår i: Scientific Data. - : Nature Portfolio. - 2052-4463. ; 8:1
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Tidskriftsartikel (refereegranskat)abstract
- We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.
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| 48. |
- Hruska, Kimberly A., et al.
(författare)
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Influences of Sex and Activity Level on Physiological Changes in Individual Adult Sockeye Salmon during Rapid Senescence
- 2010
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Ingår i: Physiological and Biochemical Zoology. - : University of Chicago Press. - 1522-2152 .- 1537-5293. ; 83:4, s. 663-676
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Tidskriftsartikel (refereegranskat)abstract
- A noninvasive biopsy protocol was used to sample plasma and gill tissue in individual sockeye salmon (Oncorhynchus nerka) during the critical life stage associated with spawning-arrival at a spawning channel through senescence to death several days later. Our main objective was to characterize the physiological changes associated with rapid senescence in terms of the physiological stress/cortisol hypersecretion model and the energy exhaustion model. Salmon lived an average of 5 d in the spawning channel, during which time there were three major physiological trends that were independent of sexual status: a large increase in plasma indicators of stress and exercise (i.e., lactate and cortisol), a decrease in the major plasma ions (i.e., Cl(-) and Na(+)) and osmolality, and a decrease in gross somatic energy reserves. Contrary to a generalized stress response, plasma glucose decreased in approximately 2/3 of the fish after arrival, as opposed to increasing. Furthermore, plasma cortisol levels at spawning-ground arrival were not correlated with the degree of ionoregulatory changes during rapid senescence. One mechanism of mortality in some fish may involve the exhaustion of energy reserves, resulting in the inability to mobilize plasma glucose. Sex had a significant modulating effect on the degree of physiological change. Females exhibited a greater magnitude of change for gross somatic energy, osmolality, and plasma concentrations of Cl(-), Na(+), cortisol, testosterone, 11-ketotestosterone, 17,20 beta-progesterone, and estradiol. The activity level of an individual on the spawning grounds appeared to influence the degree of some physiological changes during senescence. For example, males that received a greater frequency of attacks exhibited larger net decreases in plasma 11-ketotestosterone while on the spawning grounds. These results suggest that rapid senescence on spawning grounds is influenced by multiple physiological processes and perhaps behavior. This study provides some of the first data to look at sex differences in senescence in Pacific salmon.
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| 49. |
- Altimiras, Jordi, 1967-, et al.
(författare)
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Gastrointestinal blood flow and postprandial metabolism in swimming sea bass dicentrarchus labrax
- 2008
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Ingår i: Physiological and Biochemical Zoology. - : University of Chicago Press. - 1522-2152 .- 1537-5293. ; 81:5, s. 663-672
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Tidskriftsartikel (refereegranskat)abstract
- In trout and salmon, the metabolic costs of exercise and feeding are additive, which would suggest that gastrointestinal blood flow during exercise is maintained to preserve digestive and absorptive processes related to the specific dynamic action (SDA) of food. However, in most published studies, gastrointestinal blood flow drops during swimming, hypoxia, and general stress. To test whether gastrointestinal blood flow is spared during exercise after feeding, sea bass were instrumented with flow probes to measure cardiac output and celiacomesenteric blood flow while swimming in a respirometer before and after feeding. Swimming at 2 body lengths per second (bl s-1) increased metabolic rate considerably more than did feeding (208% vs. 32% increase, respectively, relative to resting), and a similar pattern was observed for cardiac output. In unfed fish, resting gastrointestinal blood flow was mL 13.8 ± 0.5 min-1 kg-1. After feeding, resting gastrointestinal blood flow increased by 82% but then decreased progressively with increasing swimming speeds. At 2 bl s-1, gastrointestinal blood flow in fed fish was not significantly different compared with that in unfed swimming fish, and, therefore, the data do not support the gastrointestinal sparing hypothesis. The magnitude of the SDA was maintained despite the decrease in gastrointestinal blood flow and the consequent reduction in oxygen supply to the gut. An estimate of maximal oxygen flow to the gastrointestinal tract after feeding yielded 2.6 mmol O2 h-1 kg-1, but this amount is not able to cover the oxygen demand of 3.16 mmol O2 h -1 kg-1. Therefore, the SDA must reflect metabolic processes in tissues other than those directly perfused by the celiacomesenteric artery. © 2008 by The University of Chicago. All rights reserved.
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| 50. |
- Egginton, S., et al.
(författare)
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Maximum cardiac performance of Antarctic fishes that lack haemoglobin and myoglobin: exploring the effect of warming on nature's natural knockouts
- 2019
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Ingår i: Conservation Physiology. - : Oxford University Press (OUP). - 2051-1434. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Antarctic notothenioids, some of which lack myoglobin (Mb) and/or haemoglobin (Hb), are considered extremely stenothermal, which raises conservation concerns since Polar regions are warming at unprecedented rates. Without reliable estimates of maximum cardiac output (((Q)over dot)), it is impossible to assess their physiological scope in response to warming seas. Therefore, we compared cardiac performance of two icefish species, Chionodraco rastrospinosus (Hb(-)Mb(+)) and Chaenocephalus aceratus (Hb(-)Mb(-)), with a related notothenioid, Notothenia coriiceps (Hb(+)Mb(+)) using an in situ perfused heart preparation. The maximum (Q)over dot, heart rate (f(H)), maximum cardiac work (WC) and relative ventricular mass of N. coriiceps at 1 degrees C were comparable to temperate-water teleosts, and acute warming to 4 degrees C increased fH and WC, as expected. In contrast, icefish hearts accommodated a higher maximum stroke volume (VS) and maximum. Q at 1 degrees C, but their unusually large hearts had a lower fH and maximum afterload tolerance than N. coriiceps at 1 degrees C. Furthermore, maximum VS, maximum. Q and fH were all significantly higher for the Hb(-)Mb(+) condition compared with the Hb(-)Mb(-) condition, a potential selective advantage when coping with environmental warming. Like N. coriiceps, both icefish species increased H-f at 4 degrees C. Acutely warming C. aceratus increased maximum (Q) over dot, while C. rastrospinosus (like N. coriiceps) held at 4 degrees C for 1 week maintained maximum. Q when tested at 4 degrees C. These experiments involving short-term warming should be followed up with long-term acclimation studies, since the maximum cardiac performance of these three Antarctic species studied seem to be tolerant of temperatures in excess of predictions associated with global warming.
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