29 research outputs found
Global simulations of monoterpene-derived peroxy radical fates and the distributions of highly oxygenated organic molecules (HOMs) and accretion products
We evaluate monoterpene-derived peroxy radical (MT-RO2) unimolecular autoxidation and self- and cross-reactions with other RO2 species in the GEOS-Chem global chemical transport model. The formation of associated highly oxygenated organic molecules (HOMs) and accretion products are tracked in competition with other bimolecular reactions. Autoxidation is the dominant fate up to 6-8 km for first-generation MT-RO2, which can undergo unimolecular H shifts. Reaction with NO can be a more common fate for H-shift rate constants < 0.1 s(-1) or at altitudes higher than 8 km due to the imposed Arrhenius temperature dependence of unimolecular H shifts. For MT-derived HOM-RO2, generated by multistep autoxidation of first-generation MT-RO2, reaction with other RO2 species is predicted to be the major fate throughout most of the boreal and tropical forest regions, whereas reaction with NO dominates in the temperate and subtropical forests of the Northern Hemisphere. The newly added reactions result in an approximate 4 % global average decrease in HO2 and RO2, mainly due to faster self-/cross-reactions of MT-RO2, but the impact upon HO2, OH, and NOx abundances is only important in the planetary boundary layer (PBL) over portions of tropical forests. Predicted HOM concentrations in MT-rich regions and seasons can exceed total organic aerosol predicted by the standard version of the GEOS-Chem model depending on the parameters used. Comparisons to observations reveal that large uncertainties remain for key reaction parameters and processes, especially with respect to the photochemical lifetime and volatility of HOMs as well as the rates and branching of associated RO2 accretion products. Further observations and laboratory studies related to MT-RO2-derived HOMs and gas-phase RO2 accretion product formation kinetics - especially their atmospheric fate, such as gas-particle partitioning, multiphase chemistry, and net secondary organic aerosol formation - are needed.Peer reviewe
Monoterpenes’ oxidation capacity and rate over a boreal forest : temporal variation and connection to growth of newly formed particles
Peer reviewe
Wintertime subarctic new particle formation from Kola Peninsula sulfur emissions
The metallurgical industry in the Kola Peninsula, north-west Russia, form, after Norilsk, Siberia, the second largest source of air pollution in the Arctic and subarctic domain. Sulfur dioxide (SO2/emissions from the ore smelters are transported to wide areas, including Finnish Lapland. We performed investigations on concentrations of SO2, aerosol precursor vapours, aerosol and ion cluster size distributions together with chemical composition measurements of freshly formed clusters at the SMEAR I station in Finnish Lapland relatively close (similar to 300 km) to the Kola Peninsula industrial sites during the winter 2019-2020. We show that highly concentrated SO2 from smelter emissions is converted to sulfuric acid (H2SO4/in sufficient concentrations to drive new particle formation hundreds of kilometres downwind from the emission sources, even at very low solar radiation intensities. Observed new particle formation is primarily initiated by H2SO4-ammonia (negative-)ion-induced nucleation. Particle growth to cloud condensation nuclei (CCN) sizes was concluded to result from sulfuric acid condensation. However, air mass advection had a large role in modifying aerosol size distributions, and other growth mechanisms and condensation of other compounds cannot be fully excluded. Our results demonstrate the dominance of SO2 emissions in controlling wintertime aerosol and CCN concentrations in the subarctic region with a heavily polluting industry.Peer reviewe
ECLAIRE: Effects of Climate Change on Air Pollution Impacts and Response Strategies for European Ecosystems. Project final report
The central goal of ECLAIRE is to assess how climate change will alter the extent to which air pollutants threaten terrestrial ecosystems. Particular attention has been given to nitrogen compounds, especially nitrogen oxides (NOx) and ammonia (NH3), as well as Biogenic Volatile Organic Compounds (BVOCs) in relation to tropospheric ozone (O3) formation, including their interactions with aerosol components. ECLAIRE has combined a broad program of field and laboratory experimentation and modelling of pollution fluxes and ecosystem impacts, advancing both mechanistic understanding and providing support to European policy makers.
The central finding of ECLAIRE is that future climate change is expected to worsen the threat of air pollutants on Europe’s ecosystems.
Firstly, climate warming is expected to increase the emissions of many trace gases, such as agricultural NH3, the soil component of NOx emissions and key BVOCs. Experimental data and numerical models show how these effects will tend to increase atmospheric N deposition in future. By contrast, the net effect on tropospheric O3 is less clear. This is because parallel increases in atmospheric CO2 concentrations will offset the temperature-driven increase for some BVOCs, such as isoprene. By contrast, there is currently insufficient evidence to be confident that CO2 will offset anticipated climate increases in monoterpene emissions.
Secondly, climate warming is found to be likely to increase the vulnerability of ecosystems towards air pollutant exposure or atmospheric deposition. Such effects may occur as a consequence of combined perturbation, as well as through specific interactions, such as between drought, O3, N and aerosol exposure.
These combined effects of climate change are expected to offset part of the benefit of current emissions control policies. Unless decisive mitigation actions are taken, it is anticipated that ongoing climate warming will increase agricultural and other biogenic emissions, posing a challenge for national emissions ceilings and air quality objectives related to nitrogen and ozone pollution. The O3 effects will be further worsened if progress is not made to curb increases in methane (CH4) emissions in the northern hemisphere.
Other key findings of ECLAIRE are that: 1) N deposition and O3 have adverse synergistic effects. Exposure to ambient O3 concentrations was shown to reduce the Nitrogen Use Efficiency of plants, both decreasing agricultural production and posing an increased risk of other forms of nitrogen pollution, such as nitrate leaching (NO3-) and the greenhouse gas nitrous oxide (N2O); 2) within-canopy dynamics for volatile aerosol can increase dry deposition and shorten atmospheric lifetimes; 3) ambient aerosol levels reduce the ability of plants to conserve water under drought conditions; 4) low-resolution mapping studies tend to underestimate the extent of local critical loads exceedance; 5) new dose-response functions can be used to improve the assessment of costs, including estimation of the value of damage due to air pollution effects on ecosystems, 6) scenarios can be constructed that combine technical mitigation measures with dietary change options (reducing livestock products in food down to recommended levels for health criteria), with the balance between the two strategies being a matter for future societal discussion. ECLAIRE has supported the revision process for the National Emissions Ceilings Directive and will continue to deliver scientific underpinning into the future for the UNECE Convention on Long-range Transboundary Air Pollution
ECLAIRE third periodic report
The ÉCLAIRE project (Effects of Climate Change on Air Pollution Impacts and Response Strategies for European Ecosystems) is a four year (2011-2015) project funded by the EU's Seventh Framework Programme for Research and Technological Development (FP7)
How to Earn the Status of Honest Broker? Scientists’ Roles Facilitating the Political Water Supply Decision-Making Process
The effects and safety of telerehabilitation in patients with lower-limb joint replacement:a systematic review and narrative synthesis
Abstract
Introduction: As the number of patients undergoing primary lower-limb joint replacement has risen continuously, hospital-based healthcare resources have become limited. Delivery of any ongoing rehabilitation needs to adapt to this trend. This systematic literature aimed to examine the effects and safety of telerehabilitation in patients with lower-limb joint replacement.
Methods: A systematic review of randomized controlled trials was conducted according to procedures by the Joanna Briggs Institute. Studies published prior to February 2020 were identified from Medline Ovid, Scopus, Ebsco Databases and Web of Science. Reference lists of relevant studies were also manually checked to find additional studies. Two researchers conducted study selection separately. The Joanna Briggs Institute Critical Appraisal Checklist for Randomized Controlled Trials was used to evaluate the quality of the relevant studies published. A narrative synthesis was used to report the results whereas effect sizes were estimated for different outcomes.
Results: Nine studies with 1266 patients were included. Study quality was predominantly affected by the lack of blinding. The patients who completed telerehabilitation showed an improvement in physical functioning that was similar to that of patients completing conventional in-person outpatient physical therapy without an increase in adverse events or resource utilization. The effect of telerehabilitation on physical functioning, however, was assessed as heterogeneous and moderate- to low-quality evidence.
Discussion: Telerehabilitation is a practical alternative to conventional in-person outpatient physical therapy in patients with lower-limb joint replacement. However, more robust studies are needed to build evidence about telerehabilitation
Parental experiences of the pediatric day surgery pathway and the needs for a digital gaming solution:qualitative study
Abstract
Background: The parents of hospitalized children are often dissatisfied with waiting times, fasting, discharge criteria, postoperative pain relief, and postoperative guidance. Parents’ experiences help care providers to provide effective, family-centered care that responds to parents’ needs throughout the day surgery pathway.
Objective: The objective of our study was to describe parental experiences of the pediatric day surgery pathway and the needs for a digital gaming solution in order to facilitate the digitalization of these pathways.
Methods: This was a descriptive qualitative study. The participants (N=31) were parents whose children were admitted to the hospital for the day surgical treatments or magnetic resonance imaging. The data were collected through an unstructured, open-ended questionnaire; an inductive content analysis was conducted to analyze the qualitative data. Reporting of the study findings adheres to the Consolidated Criteria for Reporting Qualitative Research (COREQ) checklist.
Results: Parental experiences of the children’s day surgery pathway included 3 main categories: (1) needs for parental guidance, (2) needs for support, and (3) child involved in his or her own pathway (eg, consideration of an individual child and preparation of child for treatment). The needs for a digital gaming solution were identified as 1 main category—the digital gaming solution for children and families to support care. This main category included 3 upper categories: (1) preparing children and families for the day surgery via the solution, (2) gamification in the solution, and (3) connecting people through the solution.
Conclusions: Parents need guidance and support for their children’s day surgery care pathways. A digital gaming solution may be a relevant tool to support communication and to provide information on day surgeries. Families are ready for and are open to digital gaming solutions that provide support and guidance and engage children in the day surgery pathways
A gamified mobile health intervention for children in day surgery care:protocol for a randomized controlled trial
Abstract
Aims: To describe a study protocol for a randomized controlled trial which will evaluate the effectiveness of a gamified mobile health intervention for children in whole day surgery care.
Design: A study protocol for a two-arm randomized controlled trial.
Methods: Participants will be randomly assigned to the intervention group (N = 62), in which patients receive routine care and play a mobile game designed for children or the control group (N = 62), in which patients receive routine care, including a mobile phone application that supports parents during the care path. The primary outcome is children’s pre-operative anxiety, while the secondary outcome measures included fear and postoperative pain, along with parental satisfaction and anxiety. Data collection started in August 2020.
Results: The results of the ongoing randomized controlled trial will determine whether the developed gamified mobile health intervention can be recommended for hospital use, and whether it could be used to educate children about their surgical treatment to decrease anxiety