9-year trends of PM₁₀sources and oxidative potential in a rural background site in France

Long-term monitoring at sites with relatively low particulate pollution could provide an opportunity to identify changes in pollutant concentration and potential effects of current air quality policies. In this study, a 9-year sampling of PM10 (particles with an aerodynamic diameter below 10 µm) was performed in a rural background site in France from February 28, 2012 to December 22, 2020. The Positive Matrix Factorization (PMF) method was used to apportion sources of PM10 based on quantified chemical constituents and specific chemical tracers from collected filters. Oxidative potential (OP), an emerging health-metric that measures PM capability to potentially cause anti-oxidant imbalance in the lung, was also measured using two acellular assays: dithiothreitol (DTT) and ascorbic acid (AA). The contribution of PMF-resolved sources to OP were also estimated using multiple linear regression (MLR) analysis. In terms of mass contribution, the dominant sources are secondary aerosols (nitrate- and sulphate-rich), associated with long-range transport (LRT). However, in terms of OP contributions, the main drivers are traffic, mineral dust, and biomass burning factors. There is also some OP contribution apportioned to the sulphate- and nitrate-rich sources influenced by processes and aging during LRT that could have encouraged mixing with other anthropogenic sources. The study indicates much lower OP values than in urban areas. A substantial decrease (58 % reduction from year 2012 to 2020) in the mass contributions from the traffic factor was found, however, this is not clearly reflected in its OP contribution. Nevertheless, the findings in this long-term study in the OPE site could signal effectiveness of implemented emission control policies, as also seen in other long-term studies conducted in Europe, mainly for urban areas.

A study of online trading system in India

This research is related to examines the new wave of online trading with respect to industries, brokerages. Stock market is one of the important elements of the Indian economy which determines the economic growth of India and financial state of the country. In today’s world there are millions of people are connected to the internet and many of them are from rural background. Last 30 years since 1991, GPL (Globalization, Privatization, Liberalization) the internet has impacted much on people perception. The customer satisfaction is only thing that make a business successful. The present study to find out the customer awareness towards online trading. The main objective of the study is to understand the how the online trades take place. The major reason for investing in the share market is convincing and easy to handle.

Morphometric Study of Modifications over the Neck of Talus in Visakhapatnam Region of Andhra Pradesh State

BACKGROUND Talus is a very important bone among the skeleton of foot. Talus is a very common bone which undergoes some structural modifications due to prolonged habitual squatting postures. Structural alterations like squatting facets, trochlear extensions are observed over the dorsal aspect of the neck of the talus common type of squatting facets observed are medial squatting facets, lateral squatting facets, combined type of squatting facets .These are observed in specific group of people. METHODS Present study was conducted in 100 talus bones, which are procured from department of Anatomy, Andhra medical college, Visakhapatnam. Structural modifications like squatting facets, trochlear extensions are studied in all the bones. RESULTS Squatting facets are observed in most of the talus .but trochlear extensions are not observed in any of the talus .out of 100 talus, 54 tali are having lateral squatting facet, 4tali are having a medial squatting facet, 16 tali showing combined type of squatting facet, 26 tali are not having any type of squatting facets. Out of 54 right sided taluses, 24 tali are having a lateral squatting facet, 3 tali are having medial squatting facet, 10 tali are having combined type of squatting facet, 17tali are not having any type of squatting facet. Out of 46 left sided taluses, 30tali are having lateral squatting facet, 1 talus is having a medial squatting facet, 6 tali are having combined type of squatting facets, 9tali are not having any type of squatting facet. CONCLUSIONS Incidence of modifications over the neck of talus is very common in people who are having a rural background, those people are having a habitual squatting position. And these alterations may be due to genetic inheritance and several unexplainable reasons. KEYWORDS Talus, Squatting Facet, Habitual Squatting Posture, Lateral Squatting Facet, Medial Squatting Facet

A phenomenology of new particle formation (NPF) at 13 European sites

New particle formation (NPF) events occur almost everywhere in the world and can play an important role as a particle source. The frequency and characteristics of NPF events vary spatially, and this variability is yet to be fully understood. In the present study, long-term particle size distribution datasets (minimum of 3 years) from 13 sites of various land uses and climates from across Europe were studied, and NPF events, deriving from secondary formation and not traffic-related nucleation, were extracted and analysed. The frequency of NPF events was consistently found to be higher at rural background sites, while the growth and formation rates of newly formed particles were higher at roadsides (though in many cases differences between the sites were small), underlining the importance of the abundance of condensable compounds of anthropogenic origin found there. The growth rate was higher in summer at all rural background sites studied. The urban background sites presented the highest uncertainty due to greater variability compared to the other two types of site. The origin of incoming air masses and the specific conditions associated with them greatly affect the characteristics of NPF events. In general, cleaner air masses present higher probability for NPF events, while the more polluted ones show higher growth rates. However, different patterns of NPF events were found, even at sites in close proximity (< 200 km), due to the different local conditions at each site. Region-wide events were also studied and were found to be associated with the same conditions as local events, although some variability was found which was associated with the different seasonality of the events at two neighbouring sites. NPF events were responsible for an increase in the number concentration of ultrafine particles of more than 400 % at rural background sites on the day of their occurrence. The degree of enhancement was less at urban sites due to the increased contribution of other sources within the urban environment. It is evident that, while some variables (such as solar radiation intensity, relative humidity, or the concentrations of specific pollutants) appear to have a similar influence on NPF events across all sites, it is impossible to predict the characteristics of NPF events at a site using just these variables, due to the crucial role of local conditions.

Source Apportionment and Toxicity of PM in Urban, Sub-Urban, and Rural Air Quality Network Stations in Catalonia

Air quality indicators, i.e., PM10, NO2, O3, benzo[a]pyrene, and several organic tracer compounds were evaluated in an urban traffic station, a sub-urban background station, and a rural background station of the air quality network in Catalonia (Spain) from summer to winter 2019. The main sources that contribute to the organic aerosol and PM toxicity were determined. Traffic-related air pollution dominated the air quality in the urban traffic station, while biomass burning in winter and secondary organic aerosol (SOA) in summer impact the air quality in the sub-urban and rural background stations. Health risk assessment for chronic exposure over the past decade, using WHO air quality standards, showed that NO2, PM10 and benzo[a]pyrene from traffic emissions pose an unacceptable risk to the human population in the urban traffic station. PM10 and benzo[a]pyrene from biomass burning were unacceptably high in the sub-urban and rural background stations. Toxicity tests of the PM extracts with epithelial lung cells showed higher toxicity in wintertime samples in the sub-urban and rural stations, compared to the urban traffic station. These results require different mitigation strategies for urban and rural sites in order to improve the air quality. In urban areas, traffic emissions are still dominating the air quality, despite improvements in the last years, and may directly be responsible for part of the SOA and O3 levels in sub-urban and rural areas. In these later areas, air pollution from local biomass burning emissions are dominating the air quality, essentially in the colder period of the year.