Sensitivity Analyses for Atmospheric Scavenging Ratio of Total PCDD/Fs-TEQ Wet Deposition: Case of Wuhu City, China

Abstract. Light-absorbing aerosol – particularly elemental carbon (EC) – while mixed with snow and ice is an important climate driver from the enhanced absorption of solar radiation. Currently, considerable efforts are being made to estimate its radiative forcing on a global scale, but several uncertainties remain, particularly those regarding its deposition processes. In this study, concurrent measurements of EC in air and snow are performed for three years (2009–2012) at Changbai station, northeastern China. The scavenging ratio and the wet- and dry-deposition fluxes of EC over the snow surface are estimated. The mean EC concentration in the surface snow is 1000 ± 1500 ng g−1, ranging from 7 to 7640 ng g−1. The mean value of the scavenging ratio of EC by snow is 140 ± 100, with a median value of 150, which is smaller than that reported in Arctic areas. A non-rimed snow process is a significant factor in interpreting differences with Arctic areas. Wet-deposition fluxes of EC are estimated to be 0.47 ± 0.37 μg cm−2 month−1 on average over the three snow seasons studied. Dry deposition is more than five times higher, with an average of 2.65 ± 1.93 μg cm−2 month−1; however, only winter period estimation is possible (December–February). During winter in Changbai, 87% of EC in snow is estimated to be due to dry deposition, with a mean dry deposition velocity of 6.44 × 10−3 m s−1 and median of 8.14 × 10−3 m s−1. Finally, the calculation of the radiative effect shows that 500 ng g−1 of dry-deposited EC to a snow surface absorbs three times more incoming solar energy than the same mass mixed in the snow through wet deposition. Deposition processes of an EC-containing snow surface are, therefore, crucial to estimate its radiative forcing better, particularly in northeastern China, where local emission strongly influences the level and gradient of EC in the snowpack, and snow-covered areas are cold and dry due to the atmospheric general circulation. Furthermore, this study builds on the knowledge to characterize the conditions in the snow-laden Chinese rural areas better as well as to constrain transport of EC to the Arctic better.

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A synthesis review on atmospheric wet deposition of particulate elements: scavenging ratios, solubility and flux measurements

Environmental Reviews ◽

10.1139/er-2020-0118 ◽

2021 ◽

Author(s):

Irene Cheng ◽

Abdulla Al Mamun ◽

Leiming Zhang

Keyword(s):

Middle East ◽

Wet Deposition ◽

Ambient Air ◽

Deposition Flux ◽

Regression Equations ◽

Specific Element ◽

Deposition Fluxes ◽

Flux Measurements ◽

Scavenging Ratio ◽

Scavenging Ratios

Atmospheric dry and wet deposition of particulate matter controls its lifetime in air and contributes to the environmental burden of toxic pollutants, and thus has important implications on human and ecosystem health. This synthesis review focused on atmospheric wet deposition of particulate elements and analyzed their scavenging ratios (i.e. concentration in precipitation to that in ambient air), solubility and wet deposition flux measurements based on published studies in literature, aiming to gather updated knowledge that can be used for modeling their wet deposition. Our analysis finds that scavenging ratios of a specific element have a narrow range. Overall, elemental scavenging ratios for snow are ~3 times higher than those for rain. Elements that are bound to coarse (PM2.5-10) particles have larger scavenging ratios than those bound to fine (PM2.5) particles except for Fe and Si. Solubility of elements in rainwater range from 8% (Fe) to 94% (Ca). Solubility is moderately correlated with scavenging ratio possibly explaining the lower scavenging ratios of Fe and Si compared to other elements with similar fine fraction. Data collected from North America, Europe, the Middle East, and Asia show that the wet fluxes of Al and Fe are orders of magnitude greater than those of routinely-monitored anthropogenic elements (Zn, Pb, Cu, Ni, Cd, Cr). Wet deposition fluxes of particulate elements in the Middle East exceed those in other regions, likely due to regional transport of dust and soil resuspension. Fluxes from all regions are a factor of 2-3 greater in industrialized and urban locations than rural and remote locations because of industrial, vehicular and soil and mineral dust emissions. Dry deposition fluxes are usually greater than wet deposition fluxes although to varying degrees according to co-located measurements. Based on the relationships between scavenging ratio and elemental PM2.5 fraction under rain and snow conditions, we derived regression equations for estimating scavenging ratios of particulate elements whose measurements are limited. Such knowledge and data improves the quantification of atmospheric deposition fluxes for an expanded list of metals and metalloids and the understanding of pathways contributing to ecological risk.

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Wet deposition and scavenging ratio of air pollutants during an extreme rainstorm in the North China Plain

Atmospheric and Oceanic Science Letters ◽

10.1080/16742834.2017.1343084 ◽

2017 ◽

Vol 10 (5) ◽

pp. 348-353 ◽

Cited By ~ 6

Author(s):

Yue-Peng Pan ◽

Xia-Ying Zhu ◽

Shi-Li Tian ◽

Li-Li Wang ◽

Guo-Zhong Zhang ◽

...

Keyword(s):

Air Pollutants ◽

Wet Deposition ◽

North China Plain ◽

North China ◽

The North ◽

The North China Plain ◽

Scavenging Ratio

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Stroke Prevention in Non-Valvular Atrial Fibrillation

Hämostaseologie ◽

10.1055/s-0038-1659985 ◽

1997 ◽

Vol 17 (03) ◽

pp. 166-169

Author(s):

Judith O’Brien ◽

Wendy Klittich ◽

J. Jaime Caro

Keyword(s):

Atrial Fibrillation ◽

Clinical Trials ◽

Care Home ◽

Relevant Literature ◽

Clinical Trial Data ◽

Outcome Data ◽

Sensitivity Analyses ◽

Bleeding Events ◽

Discharge Data ◽

The Cost

SummaryDespite evidence from 6 major clinical trials that warfarin effectively prevents strokes in atrial fibrillation, clinicians and health care managers may remain reluctant to support anticoagulant prophylaxis because of its perceived costs. Yet, doing nothing also has a price. To assess this, we carried out a pharmacoe-conomic analysis of warfarin use in atrial fibrillation. The course of the disease, including the occurrence of cerebral and systemic emboli, intracranial and other major bleeding events, was modeled and a meta-analysis of the clinical trials and other relevant literature was carried out to estimate the required probabilities with and without warfarin use. The cost of managing each event, including acute and subsequent care, home care equipment and MD costs, was derived by estimating the cost per resource unit, the proportion consuming each resource and the volume of use. Unit costs and volumes of use were determined from established US government databases, all charges were adjusted using cost-to-charge ratios, and a 3% discount rate was applied to costs incurred beyond the first year. The proportions of patients consuming each resource were estimated by fitting a joint distribution to the clinical trial data, stroke outcome data from a recent Swedish study and aggregate ICD-9 specific, Massachusetts discharge data. If nothing is done, 3.2% more patients will suffer serious emboli annually and the expected annual cost of managing a patient will increase by DM 2,544 (1996 German Marks), from DM 4,366 to DM 6,910. Extensive multiway sensitivity analyses revealed that the higher price of doing nothing persists except for very extreme combinations of inputs unsupported by literature or clinical standards. The price of doing nothing is thus so high, both in health and economic terms, that cost-consciousness as well as clinical considerations mandate warfarin prophylaxis in atrial fibrillation.

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Uncertainty propagation and parameter sensitivity analyses of relative permittivity models for use in soils

10.32469/10355/44718 ◽

2013 ◽

Author(s):

Tyler J. McKee

Keyword(s):

Relative Permittivity ◽

Uncertainty Propagation ◽

Parameter Sensitivity ◽

Sensitivity Analyses

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Further research for sensitivity analyses of discrete periodic systems

AIAA Journal ◽

10.2514/3.14222 ◽

1999 ◽

Vol 37 ◽

pp. 653-656

Author(s):

Ying Gu ◽

Lifen Chen ◽

Wenliang Wang

Keyword(s):

Sensitivity Analyses ◽

Periodic Systems

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Indicated preventive interventions for anxiety in children and adolescents: a review and meta-analysis of school based programs

10.31234/osf.io/jadxq ◽

2019 ◽

Author(s):

Siobhan Hugh-Jones ◽

Sophie Beckett ◽

Pavan Mallikarjun

Keyword(s):

Meta Analysis ◽

Child And Adolescent ◽

Sensitivity Analyses ◽

Cochrane Library ◽

Control Groups ◽

Adolescent Anxiety ◽

School Based ◽

Intervention Intensity ◽

Randomised Controlled ◽

And Control

Schools are promising sites for the delivery of prevention and early intervention programs to reduce child and adolescent anxiety. It is unclear whether universal or targeted approaches are most effective. This review and meta-analysis examines the effectiveness of school-based indicated interventions and was registered with PROSPERO [CRD42018087628].MEDLINE, EMBASE, PsycINFO and the Cochrane Library were searched for randomised controlled trials comparing indicated school programs for child and adolescent anxiety to active or inactive control groups. Twenty original studies, with 2076 participants, met the inclusion criteria and 18 were suitable for meta-analysis. Sub-group and sensitivity analyses explored intervention intensity, delivery agent and control type. A small beneficial effect was found for indicated programs compared to controls on self-reported anxiety symptoms at post-test (g = -0.28, CI = -0.50, -0.05, k= 18). The small effect was maintained at 6 (g = -0.35, CI= -0.58, -0.13, k = 9) and 12 months (g = -0.24, CI = -0.48, 0.00, k = 4). Based on two studies, >12 month effects were very small (g = -0.01, CI= -0.38, 0.36). No differences were found based on intervention intensity, delivery agent and control type. There was evidence of publication bias and a relatively high risk of contamination in studies. Findings support the value of school based indicated programs for child and adolescent anxiety. Effects at 12 months outperform many universal programs. High quality, randomised controlled and pragmatic trials are needed, with attention control groups and beyond 12 month diagnostic assessments are needed.

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Quality of wet deposition in the Grand Calumet River Watershed, northwestern Indiana, October 17, 1995–November 12, 1996

10.3133/wri994253 ◽

2000 ◽

Keyword(s):

Wet Deposition ◽

River Watershed ◽

October 17

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A SIMPLIFIED ANALYTICAL PROCEDURE FOR SEISMIC ANALYSIS OF TIMBER LIGHT-FRAME SHEAR WALLS

NED University Journal of Research ◽

10.35453/nedjr-stmech-2019-0054 ◽

2019 ◽

Vol 3 (Special Issue on First SACEE'19) ◽

pp. 173-180

Author(s):

Giorgia Di Gangi ◽

Giorgio Monti ◽

Giuseppe Quaranta ◽

Marco Vailati ◽

Cristoforo Demartino

Keyword(s):

Analytical Procedure ◽

Seismic Analysis ◽

Shear Walls ◽

Element Model ◽

Sensitivity Analyses ◽

Width Ratio ◽

Damping Factor ◽

Equivalent Viscous Damping ◽

Design Variables ◽

Depth Analysis

The seismic performance of timber light-frame shear walls is investigated in this paper with a focus on energy dissipation and ductility ensured by sheathing-to-framing connections. An original parametric finite element model has been developed in order to perform sensitivity analyses. The model considers the design variables affecting the racking load-carrying capacity of the wall. These variables include aspect ratio (height-to-width ratio), fastener spacing, number of vertical studs and framing elements cross-section size. A failure criterion has been defined based on the observation of both the global behaviour of the wall and local behaviour of fasteners in order to identify the ultimate displacement of the wall. The equivalent viscous damping has been numerically assessed by estimating the damping factor which is in use in the capacity spectrum method. Finally, an in-depth analysis of the results obtained from the sensitivity analyses led to the development of a simplified analytical procedure which is able to predict the capacity curve of a timber light-frame shear wall.

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A Primer on the Assessment of Economic Impacts of Leisure Events

Event Management ◽

10.3727/152599518x15299559637662 ◽

2020 ◽

Vol 24 (1) ◽

pp. 47-56

Author(s):

Ove Oklevik ◽

Grzegorz Kwiatkowski ◽

Mona Kristin Nytun ◽

Helene Maristuen

Keyword(s):

Impact Assessment ◽

Economic Impact ◽

Study Design ◽

Impact Analysis ◽

Sensitivity Analyses ◽

Primary Data ◽

Music Festival ◽

Economic Impact Analysis ◽

Economic Impact Assessment ◽

Input Variables

The quality of any economic impact assessment largely depends on the adequacy of the input variables and chosen assumptions. This article presents a direct economic impact assessment of a music festival hosted in Norway and sensitivity analyses of two study design assumptions: estimated number of attendees and chosen definition (size) of the affected area. Empirically, the article draws on a state-of-the-art framework of an economic impact analysis and uses primary data from 471 event attendees. The results show that, first, an economic impact analysis is a complex task that requires high precision in assessing different monetary flows entering and leaving the host region, and second, the study design assumptions exert a tremendous influence on the final estimation. Accordingly, the study offers a fertile agenda for local destination marketing organizers and event managers on how to conduct reliable economic impact assessments and explains which elements of such analyses are particularly important for final estimations.

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