Long-term variability of the air pollution sources reflected on the state of mixing of the urban aerosol

2019 ◽  
Vol 8 ◽  
pp. 36-39 ◽  
Author(s):  
Konstantinos Eleftheriadis
Keyword(s):  
Air Pollution ◽  
The State ◽  
Pollution Sources ◽  
Urban Aerosol

scholarly journals Urban aerosol size distributions: a global perspective

2021 ◽  
Vol 21 (11) ◽  
pp. 8883-8914
Author(s):  
Tianren Wu ◽  
Brandon E. Boor
Keyword(s):  
Air Pollution ◽  
Human Health ◽  
Global Perspective ◽  
Effective Density ◽  
Urban Aerosol ◽  
Size Distributions ◽  
Accumulation Mode ◽  
Coarse Mode ◽  
Geographical Regions

Abstract. Urban aerosol measurements are necessary to establish associations between air pollution and human health outcomes and to evaluate the efficacy of air quality legislation and emissions standards. The measurement of urban aerosol particle size distributions (PSDs) is of particular importance as they enable characterization of size-dependent processes that govern a particle's transport, transformation, and fate in the urban atmosphere. PSDs also improve our ability to link air pollution to health effects through evaluation of particle deposition in the respiratory system and inhalation toxicity. To inform future measurements of urban aerosol observations, this paper reviews and critically analyzes the current state of knowledge on urban aerosol PSD measurements by synthesizing 737 PSD observations made between 1998 to 2017 in 114 cities in 43 countries around the globe. Significant variations in the shape and magnitude of urban aerosol number and mass PSDs were identified among different geographical regions. In general, number PSDs in Europe (EU) and North America, Australia, and New Zealand (NAAN) are dominated by nucleation- and Aitken-mode particles. PSDs in Central, South, and Southeast Asia (CSSA) and East Asia (EA) are shifted to larger sizes, with a meaningful contribution from the accumulation mode. Urban mass PSDs are typically bimodal, presenting a dominant mode in the accumulation mode and a secondary mode in the coarse mode. Most PSD observations published in the literature are short-term, with only 14 % providing data for longer than 6 months. There is a paucity of PSDs measured in Africa (AF), CSSA, Latin America (LA), and West Asia (WA), demonstrating the need for long-term aerosol measurements across wide size ranges in many cities around the globe. Geographical variations in urban aerosol effective densities were also reviewed. Size-resolved urban aerosol effective density functions from 3 to 10 000 nm were established for different geographical regions and intra-city sampling locations in order to accurately translate number PSDs to mass PSDs, with significant variations observed between near-road and urban background sites. The results of this study demonstrate that global initiatives are urgently needed to develop infrastructure for routine and long-term monitoring of urban aerosol PSDs spanning the nucleation to coarse mode. Doing so will advance our understanding of spatiotemporal trends in urban PSDs throughout the world and provide a foundation to more reliably elucidate the impact of urban aerosols on atmospheric processes, human health, and climate.

scholarly journals Differential Probability Functions for Investigating Long-term Changes in Local and Regional Air Pollution Sources

2019 ◽  
Vol 19 (4) ◽  
pp. 724-736 ◽  
Author(s):  
Mauro Masiol ◽  
Stefania Squizzato ◽  
Meng-Dawn Cheng ◽  
David Q. Rich ◽  
Philip K. Hopke
Keyword(s):  
Air Pollution ◽  
Pollution Sources ◽  
Differential Probability ◽  
Probability Functions ◽  
Long Term Changes ◽  
Regional Air Pollution

scholarly journals Urban Aerosol Size Distributions: A Global Perspective

2020 ◽  
Author(s):  
Tianren Wu ◽  
Brandon E. Boor
Keyword(s):  
Air Pollution ◽  
Human Health ◽  
Respiratory System ◽  
Effective Density ◽  
Urban Aerosol ◽  
Size Distributions ◽  
Urban Aerosols ◽  
Accumulation Mode ◽  
Geographical Regions

Abstract. Urban aerosol measurements are necessary to establish associations between air pollution and human health outcomes and to evaluate the efficacy of air quality legislation and emissions standards. The measurement of urban aerosol particle size distributions (PSDs) is of particular importance as they enable for characterization of size-dependent processes that govern a particle’s transport, transformation, and fate in the urban atmosphere. PSDs also improve our ability to link air pollution to health effects through evaluation of particle deposition in the respiratory system and inhalation toxicity. To provide guidance for the evolution of urban aerosol observations, this paper reviews and critically analyzes the current state-of-knowledge on urban aerosol PSD measurements by synthesizing n = 793 PSD observations made between 1998 to 2017 in n = 125 cities in n = 51 countries around the globe. Significant variations in the shape and magnitude of urban aerosol number and mass PSDs were identified among different geographical regions. In general, number PSDs in Europe (EU), North America, Australia, and New Zealand (NAAN) are dominated by nucleation and Aitken mode particles. PSDs in Central, South, and Southeast Asia (CSSA) and East Asia (EA) are shifted to larger sizes, with a meaningful contribution from the accumulation mode. Urban mass PSDs are typically bi-modal, presenting a dominant peak in the accumulation mode and a secondary peak in the coarse mode. Most PSD observations published in the literature are short-term, with only 14 % providing data for longer than six months. There is a paucity of PSDs measured in Africa (AF), CSSA, Latin America (LA), and West Asia (WA), demonstrating the need for long-term aerosol measurements across wide size ranges in many cities around the globe. Inter-region variations in PSDs have important implications for population exposure, driving large differences in the urban aerosol inhaled deposited dose rate received in each region of the human respiratory system. Similarly, inter-region variations in the shape of PSDs impact the penetration of urban aerosols through filters in building ventilation systems, which serve as an important interface between the outdoor and indoor atmospheres. Geographical variations in urban aerosol effective densities were also reviewed. Size-resolved urban aerosol effective density functions from 3 to 10 000 nm were established for different geographical regions and intra-city sampling locations in order to accurately translate number PSDs to mass PSDs, with significant variations observed between near-road and urban background sites. The results of this critical review demonstrate that global initiatives are urgently needed to develop infrastructure for routine and long-term monitoring of urban aerosol PSDs spanning the nucleation to coarse modes. Doing so will advance our understanding of spatiotemporal trends in urban PSDs throughout the world and provide a foundation to more reliably elucidate the impact of urban aerosols on atmospheric processes, human health, and climate.

Power Projects and Covid-19: A Practical Analysis of the Relevance of Force Majeure Clauses under the Standardised Power Purchase and Implementation Agreements of Uganda

2020 ◽  
Vol 1 (2) ◽  
pp. 189-193
Author(s):  
Aisha Naiga ◽  
Loyola Rwabose Karobwa
Keyword(s):  
Renewable Energy ◽  
Renewable Energy Sources ◽  
Clean Energy ◽  
The State ◽  
Energy Sources ◽  
Policy Goals ◽  
Force Majeure ◽  
Practical Analysis ◽  
Energy Justice

Over 90% of Uganda's power is generated from renewable sources. Standardised Implementation Agreements and Power Purchase Agreements create a long-term relationship between Generating Companies and the state-owned off-taker guaranteed by Government. The COVID-19 pandemic and measures to curb the spread of the virus have triggered the scrutiny and application of force majeure (FM) clauses in these agreements. This article reviews the FM clauses and considers their relevance. The authors submit that FM clauses are a useful commercial tool for achieving energy justice by ensuring the continuity of the project, despite the dire effects of the pandemic. Proposals are made for practical considerations for a post-COVID-19 future which provides the continued pursuit of policy goals of promoting renewable energy sources and increasing access to clean energy, thus accelerating just energy transitions.

Individual mechanisms underlying peripheral nerve damage when exposed to metallic mercury

2020 ◽  
Vol 60 (12) ◽  
pp. 918-924
Author(s):  
Dina V. Rusanova ◽  
Oleg L. Lakhman ◽  
Galina M. Bodienkova ◽  
Irina V. Kudaeva ◽  
Natalya G. Kuptsova
Keyword(s):  
Peripheral Nerve ◽  
Peripheral Nerves ◽  
Blood Circulation ◽  
The State ◽  
Contact Period ◽  
Peripheral Nerve Damage ◽  
Demyelinating Disorders ◽  
Peripheral Blood Circulation ◽  
Antibodies To Dna

Introduction. There is a lack of knowledge of the pathophysiological mechanisms that form peripheral nerve disorders in mercury lesions of professional origin. The study aims to reveal the mechanisms underlying peripheral nerve damage in the long-term post-contact period of chronic mercury intoxication (CMI). Materials and methods. Fifty-one people had the diagnosis of a long-term period of CMI. The post-contact period was 8.5±2.6 years. The authors compared the results with a control group of 26 healthy men who had no contact with toxic substances. Stimulating electroneuromyography was performed. We studied the body systems that could contribute to the formation of disorders in the peripheral nerves. Changes in peripheral hemodynamics were studied using reovasography. The content of autoantibodies, neuron-specific enolase, serotonin, histamine, catecholamines (epinephrine, dopamine), metanephrine, and neurotrophin-3 was reviewed. The content of ceruloplasmin, secondary products of lipid peroxidation processes, reduced glutathione, the activity of superoxide dismutase and the content of nitric oxide levels were determined. Results. The study established pathogenetic structural links of peripheral nerve disorders. The autoimmune process's role was to increase the range of antibodies to the MAG protein and increase the level of antibodies to DNA. Violations of elastic-tonic properties of peripheral vessels could be associated with the functional state of motor axons. The increased content of neurotransmitters is related to the state of peripheral blood circulation; the most pronounced changes were on the legs, which could contribute to the occurrence and maintenance of vasoconstriction. The role of oxidative stress in the formation of demyelinating disorders in patients' peripheral nerves in the long-term period of CRI is possible. Conclusion. Neuroimmunological processes has an essential role in the development of peripheral nerve demyelination was shown, which consists in an increase in the content of antibodies to the MAG protein expressed on Schwann cells of peripheral nerves and in an increase in the level of antibodies to DNA involved in the formation of demyelinating changes when exposed to metallic mercury. The revealed pathological changes in the state of the peripheral blood circulation, characterized by a violation of the vessels' elastic-tonic properties, leading to demyelination of motor axons in patients in the long-term period of CMI. The increased content of neurotransmitters in the examined is of great importance in the state of peripheral circulation. Pronounced changes in blood circulation are established on the lower extremities, which may be associated with the predominance of α-adrenergic receptors in the arterial bed and may contribute to the occurrence and maintenance of vasoconstriction in the legs. The relationship between changes in indicators of oxidative stress, consisting of a decrease in the value of superoxide dismutase and reduced glutathione, and the formation of demyelinating disorders of peripheral nerves in patients in the long-term period of CMI has been proved.

Investigations on potential methods for the long-term monitoring of the state of fuel elements in dry storage casks

Kerntechnik ◽  
2018 ◽  
Vol 83 (6) ◽  
pp. 513-522 ◽  
Author(s):  
U. Hampel ◽  
A. Kratzsch ◽  
R. Rachamin ◽  
M. Wagner ◽  
S. Schmidt ◽  
...  
Keyword(s):  
The State ◽  
Dry Storage ◽  
Long Term Monitoring ◽  
Potential Methods ◽  
Fuel Elements ◽  
Term Monitoring

STATE REGULATION OF THE FINANCIAL SERVICES MARKET IN UKRAINE

2018 ◽  
Vol 1 (11) ◽  
pp. 30-47
Author(s):  
Lyudmila Nikolayevna Akimova ◽  
Alla Vasilievna Lysachok
Keyword(s):  
Life Insurance ◽  
Financial Services ◽  
Credit Unions ◽  
State Regulation ◽  
The State ◽  
Existing Problems ◽  
Insurance Contracts ◽  
State Pension

The essence of such concepts is “financial service”, “financial ser- vices market”, and “participants of the financial services market”; determined the purpose of state regulation of the financial services market; forms of state regu- lation of the financial services market; financial services that are present in the financial services market; the structure of state regulation bodies of the financial services market in Ukraine is given; The role of state bodies in the regulation of the financial services market was studied; to characterize the regulatory le- gal regulation of the financial services market in Ukraine; the main problems of functioning of the domestic market of financial services are revealed; ways to solve existing problems. It is grounded that the state regulation of financial ser- vices markets consists in the state’s implementation of a set of measures aimed at regulating and overseeing financial services markets to protect the interests of financial services consumers and preventing crisis phenomena. It is concluded that the financial services market is an important element of the development of the economy as a whole, in particular, it concerns not only the state but also society. We must understand that when this market is settled, that is, all bodies that carry out state regulation are competent in their powers, only then will we make informed, effective decisions about the normal and effective functioning of the RFP. It is important that the data of the subjects of control do not overlap, their activities should be fixed at the legislative level. It is also worth bearing in mind that appropriate conditions must be created to create compensatory mecha- nisms in the financial services markets by developing a system for guarante- eing deposits and providing for payments under long-term life insurance contracts, non-state pension provisions, deposits with deposit accounts to credit unions, etс.

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