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Ozone-climate interactions and effects on solar ultraviolet radiation

Bais AF, Bernhard G, McKenzie RL, Aucamp PJ, Young PJ, Ilyas M, et al.

Photochem Photobiol Sci, 2019 Mar 01;18(3):602-640.
PMID: 30810565 DOI: 10.1039/c8pp90059k

This report assesses the effects of stratospheric ozone depletion and anticipated ozone recovery on the intensity of ultraviolet (UV) radiation at the Earth's surface. Interactions between changes in ozone and changes in climate, as well as their effects on UV radiation, are also considered. These evaluations focus mainly on new knowledge gained from research conducted during the last four years. Furthermore, drivers of changes in UV radiation other than ozone are discussed and their relative importance is assessed. The most important of these factors, namely clouds, aerosols and surface reflectivity, are related to changes in climate, and some of their effects on short- and long-term variations of UV radiation have already been identified from measurements. Finally, projected future developments in stratospheric ozone, climate, and other factors affecting UV radiation have been used to estimate changes in solar UV radiation from the present to the end of the 21st century. New instruments and methods have been assessed with respect to their ability to provide useful and accurate information for monitoring solar UV radiation at the Earth's surface and for determining relevant exposures of humans. Evidence since the last assessment reconfirms that systematic and accurate long-term measurements of UV radiation and stratospheric ozone are essential for assessing the effectiveness of the Montreal Protocol and its Amendments and adjustments. Finally, we have assessed aspects of UV radiation related to biological effects and human health, as well as implications for UV radiation from possible solar radiation management (geoengineering) methods to mitigate climate change.
Fulltext Protocol and statistical analysis plan for the mega randomised registry trial comparing conservative vs. liberal oxygenation targets in adults with sepsis in the intensive care unit (Mega-ROX Sepsis)

Young PJ, Al-Fares A, Aryal D, Arabi YM, Ashraf MS, Bagshaw SM, et al.

Crit Care Resusc, 2023 Jun;25(2):106-112.
PMID: 37876605 DOI: 10.1016/j.ccrj.2023.04.008

BACKGROUND: The effect of conservative vs. liberal oxygen therapy on 90-day in-hospital mortality in adults with sepsis receiving unplanned invasive mechanical ventilation in the intensive care unit (ICU) is uncertain.
OBJECTIVE: The objective of this study was to summarise the protocol and statistical analysis plan for the Mega-ROX Sepsis trial.
DESIGN SETTING AND PARTICIPANTS: The Mega-ROX Sepsis trial is an international randomised clinical trial that will be conducted within an overarching 40,000-patient registry-embedded clinical trial comparing conservative and liberal ICU oxygen therapy regimens. We anticipate that between 10,000 and 13,000 patients with sepsis who are receiving unplanned invasive mechanical ventilation in the ICU will be enrolled in this trial.
MAIN OUTCOME MEASURES: The primary outcome is in-hospital all-cause mortality up to 90 days from the date of randomisation. Secondary outcomes include duration of survival, duration of mechanical ventilation, ICU length of stay, hospital length of stay, and the proportion of patients discharged home.
RESULTS AND CONCLUSIONS: Mega-ROX Sepsis will compare the effect of conservative vs. liberal oxygen therapy on 90-day in-hospital mortality in adults with sepsis who are receiving unplanned invasive mechanical ventilation in the ICU. The protocol and a prespecified approach to analyses are reported here to mitigate analysis bias.
Fulltext Protocol and statistical analysis plan for the mega randomised registry trial comparing conservative vs. liberal oxygenation targets in adults with nonhypoxic ischaemic acute brain injuries and conditions in the intensive care unit (Mega-ROX Brains)

Young PJ, Al-Fares A, Aryal D, Arabi YM, Ashraf MS, Bagshaw SM, et al.

Crit Care Resusc, 2023 Mar;25(1):53-59.
PMID: 37876994 DOI: 10.1016/j.ccrj.2023.04.011

BACKGROUND: The effect of conservative vs. liberal oxygen therapy on 90-day in-hospital mortality in adults who have nonhypoxic ischaemic encephalopathy acute brain injuries and conditions and are receiving invasive mechanical ventilation in the intensive care unit (ICU) is uncertain.
OBJECTIVE: The objective of this study was to summarise the protocol and statistical analysis plan for the Mega-ROX Brains trial.
DESIGN SETTING AND PARTICIPANTS: Mega-ROX Brains is an international randomised clinical trial, which will be conducted within an overarching 40,000-participant, registry-embedded clinical trial comparing conservative and liberal ICU oxygen therapy regimens. We expect to enrol between 7500 and 9500 participants with nonhypoxic ischaemic encephalopathy acute brain injuries and conditions who are receiving unplanned invasive mechanical ventilation in the ICU.
MAIN OUTCOME MEASURES: The primary outcome is in-hospital all-cause mortality up to 90 d from the date of randomisation. Secondary outcomes include duration of survival, duration of mechanical ventilation, ICU length of stay, hospital length of stay, and the proportion of participants discharged home.
RESULTS AND CONCLUSIONS: Mega-ROX Brains will compare the effect of conservative vs. liberal oxygen therapy regimens on 90-day in-hospital mortality in adults in the ICU with acute brain injuries and conditions. The protocol and planned analyses are reported here to mitigate analysis bias.
TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry (ACTRN 12620000391976).
Fulltext Protocol and statistical analysis plan for the mega randomised registry trial comparing conservative vs. liberal oxygenation targets in adults in the intensive care unit with suspected hypoxic ischaemic encephalopathy following a cardiac arrest (Mega-ROX HIE)

Young PJ, Al-Fares A, Aryal D, Arabi YM, Ashraf MS, Bagshaw SM, et al.

Crit Care Resusc, 2024 Jun;26(2):87-94.
PMID: 39072241 DOI: 10.1016/j.ccrj.2024.03.004

BACKGROUND: The effect of conservative vs. liberal oxygen therapy on 90-day in-hospital mortality in adults with hypoxic ischaemic encephalopathy (HIE) following a cardiac arrest who are receiving invasive mechanical ventilation in the intensive care unit (ICU) is uncertain.
OBJECTIVE: To summarise the protocol and statistical analysis plan for the Mega-ROX HIE trial.
DESIGN SETTING AND PARTICIPANTS: Mega-ROX HIE is an international randomised clinical trial that will be conducted within an overarching 40,000-participant registry-embedded clinical trial comparing conservative and liberal ICU oxygen therapy regimens. We expect to enrol approximately 4000 participants with suspected HIE following a cardiac arrest who are receiving invasive mechanical ventilation in the ICU.
MAIN OUTCOME MEASURES: The primary outcome is in-hospital all-cause mortality up to 90 days from the date of randomisation. Secondary outcomes include duration of survival, duration of mechanical ventilation, ICU length of stay, hospital length of stay, and the proportion of participants discharged home.
RESULTS AND CONCLUSIONS: Mega-ROX HIE will compare the effect of conservative vs. liberal oxygen therapy regimens on day-90 in-hospital mortality in adults in the ICU with suspected HIE following a cardiac arrest. The protocol and planned analyses are reported here to mitigate analysis bias.
TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry (ACTRN 12620000391976).
Fulltext The impact of local surface changes in Borneo on atmospheric composition at wider spatial scales: coastal processes, land-use change and air quality

Pyle JA, Warwick NJ, Harris NR, Abas MR, Archibald AT, Ashfold MJ, et al.

Philos Trans R Soc Lond B Biol Sci, 2011 Nov 27;366(1582):3210-24.
PMID: 22006963 DOI: 10.1098/rstb.2011.0060

We present results from the OP3 campaign in Sabah during 2008 that allow us to study the impact of local emission changes over Borneo on atmospheric composition at the regional and wider scale. OP3 constituent data provide an important constraint on model performance. Treatment of boundary layer processes is highlighted as an important area of model uncertainty. Model studies of land-use change confirm earlier work, indicating that further changes to intensive oil palm agriculture in South East Asia, and the tropics in general, could have important impacts on air quality, with the biggest factor being the concomitant changes in NO(x) emissions. With the model scenarios used here, local increases in ozone of around 50 per cent could occur. We also report measurements of short-lived brominated compounds around Sabah suggesting that oceanic (and, especially, coastal) emission sources dominate locally. The concentration of bromine in short-lived halocarbons measured at the surface during OP3 amounted to about 7 ppt, setting an upper limit on the amount of these species that can reach the lower stratosphere.