scholarly journals Ecological Assessment of Particulate Material (PM5 and PM10) in Urban Habitats

Atmosphere ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 559 ◽  
Author(s):  
Edina Simon ◽  
Vanda Éva Molnár ◽  
Béla Tóthmérész ◽  
Szilárd Szabó
Keyword(s):  
Gravimetric Method ◽  
Diffraction Method ◽  
Biological Indicators ◽  
Laser Diffraction ◽  
Particulate Material ◽  
Diffraction Measurement ◽  
Tree Leaves ◽  
Dust Deposition ◽  
Positive Correlation ◽  
Significant Difference

Trees are especially useful biological indicators. We tested the suitability of tree leaves (Common Lime) to assess PM5 and PM10 deposition in the three summer months of 2018 in Debrecen city, Hungary. We also tested the usefulness of the cheap and simple gravimetric method to assess the PM deposition, and compared to the expensive, but standard laser diffraction method. We found significant differences between the concentrations of PM10 deposited on tree leaves, and on dust traps. A significant difference was found in the concentration of PM5 only in July. A significant difference was also found in the concentration of PM10 among months based on leaves and dust traps. For PM5 there was a significant difference among months based on leaves deposition. We found a significant positive correlation between the PM10 concentration deposited on leaves and on dust traps. A positive correlation was found between the concentration of PM based on the gravimetric and laser diffraction measurement methods. Our findings pointed out the particulate material’s washing by rain from leaves; thus, dust deposition on the surface of leaves is limited. Our results demonstrated that trees play an important role in the mitigation of air pollution, and they are a useful indicator of PM deposition for biomonitoring studies.

Measurement of soil dry aggregate size distribution using the laser diffraction method

2021 ◽  
Vol 211 ◽  
pp. 105023
Author(s):  
C. Polakowski ◽  
A. Sochan ◽  
M. Ryżak ◽  
M. Beczek ◽  
R. Mazur ◽  
...  
Keyword(s):  
Size Distribution ◽  
Diffraction Method ◽  
Aggregate Size ◽  
Laser Diffraction ◽  
Aggregate Size Distribution

scholarly journals Particle Size Distribution of Various Soil Materials Measured by Laser Diffraction—The Problem of Reproducibility

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 465
Author(s):  
Cezary Polakowski ◽  
Magdalena Ryżak ◽  
Agata Sochan ◽  
Michał Beczek ◽  
Rafał Mazur ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Normal Distribution ◽  
Size Distribution ◽  
Precise Measurement ◽  
Soil Analysis ◽  
Statistical Tests ◽  
Diffraction Method ◽  
Laser Diffraction ◽  
Method Analysis

Particle size distribution is an important soil parameter—therefore precise measurement of this characteristic is essential. The application of the widely used laser diffraction method for soil analysis continues to be a subject of debate. The precision of this method, proven on homogeneous samples, has been implicitly extended to soil analyses, but this has not been sufficiently well confirmed in the literature thus far. The aim of this study is to supplement the information available on the precision of the method in terms of reproducibility of soil measurement and whether the reproducibility of soil measurement is characterized by a normal distribution. To estimate the reproducibility of the laser diffraction method, thirteen various soil samples were characterized, and results were analysed statistically. The coefficient of variation acquired was lowest (3.44%) for silt and highest for sand (23.28%). Five of the thirteen tested samples were characterized by a normal distribution. The fraction content of eight samples was not characterized by normal distribution, but the extent of this phenomenon varied between soils. Although the laser diffraction method is repeatable, the measurement of soil particle size distribution can have limited reproducibility. The main cause seems to be small amounts of sand particles. The error can be amplified by the construction of the dispersion unit. Non-parametric statistical tests should be used by default for soil laser diffraction method analysis.

Predictors of influenza vaccination uptake among elderly in Croatia

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
I Miskulin ◽  
A Vcev ◽  
M Matic Licanin ◽  
I Vcev ◽  
I Vukoja ◽  
...  
Keyword(s):  
Influenza Vaccination ◽  
Vaccination Coverage ◽  
Median Number ◽  
Cross Sectional ◽  
Positive Correlation ◽  
Positive Attitudes ◽  
Significant Difference ◽  
Vaccination History ◽  
Study Population ◽  
Effective Public Health

Abstract Background Influenza vaccination (IV) is recommended for elderly but vaccination coverage in this group remains unsatisfactory in Croatia. The aim of this study was to explore IV uptake among elderly from Eastern Croatia and predictors that influence this uptake. Methods This cross-sectional questionnaire study was conducted during 2018/2019 influenza season in convenient sample of older adults aged 65 years or more from Eastern Croatia at the primary health care setting. Results The study sample consisted of 816 subjects (48.0% males and 52.0% females). The median age of all subjects was 73.0 years (interquartile range (IQR) 69.5 - 79.0 years). The overall prevalence of IV uptake was 33.3%. The IV uptake was statistically more frequent among females (P < 0.001) and old-old subgroup (85 years and older) (P < 0.001). There was no statistically significant difference in IV uptake considering marital status of subjects (P > 0.999). The median number of positive attitudes towards IV was 4.0 (IQR 2.0 - 4.0) and the median number of correct answers was 6.0 (IQR 4.0 - 8.0). The study revealed fair positive correlation between attitudes and IV uptake (rho=0.477; P < 0.001) and poor positive correlation between knowledge and IV uptake (rho=0.242; P < 0.001). The study further showed poor positive correlation between presence of comorbidities and IV uptake (rho=0.187; P < 0.001) and moderate positive correlation between previous year vaccination history and IV uptake (rho=0.669; P < 0.001). Conclusions The study showed that observed IV uptake is far below EU target influenza vaccination coverage among elderly of 75%. The study revealed that fairly good predictors of IV uptake in study population were gender, older age group, and previous year vaccination history while attitudes, knowledge and presence of comorbidities were fairly poor predictors. The good predictors of IV uptake among elderly should be taken into account during influenza vaccination popularization strategies development. Key messages Understanding the factors that could improve the acceptance of vaccination is crucial to design effective public health interventions. The structured communication campaigns on influenza and influenza vaccines should be developed and directed specifically to elderly as one of target groups for vaccination.

Validation of Laser Diffraction Method as a Substitute for Cascade Impaction in the European Project for a Nebulizer Standard

2001 ◽  
Vol 14 (1) ◽  
pp. 107-114 ◽  
Author(s):  
L. Vecellio None ◽  
D. Grimbert ◽  
M.H. Becquemin ◽  
E. Boissinot ◽  
A. Le Pape ◽  
...  
Keyword(s):  
Diffraction Method ◽  
Laser Diffraction ◽  
European Project ◽  
Cascade Impaction

scholarly journals Influence of the Matrix Grain Size on the Apparent Density and Bending Strength of Sand Cores

2017 ◽  
Vol 17 (1) ◽  
pp. 27-30
Author(s):  
R. Dańko
Keyword(s):  
Grain Size ◽  
Apparent Density ◽  
Bending Strength ◽  
Diffraction Method ◽  
Laser Diffraction ◽  
Grain Sizes ◽  
The Matrix

Abstract The results of investigations of the influence of the matrix grain sizes on properties of cores made by the blowing method are presented in the hereby paper. Five kinds of matrices, differing in grain size compositions, determined by the laser diffraction method in the Analysette 22NanoTec device, were applied in investigations. Individual kinds of matrices were used for making core sands in the Cordis technology. From these sands the shaped elements, for determining the apparent density of compacted sands and their bending strength, were made by the blowing method. The shaped elements (cores) were made at shooting pressures being 3, 4 and 5 atn. The bending strength of samples were determined directly after their preparation and after the storing time of 1 hour.

scholarly journals Applicability of laser diffraction analyses in soil physics practice

2016 ◽  
Vol 5 (1-2) ◽  
pp. 32-37
Author(s):  
András Makó ◽  
József Szabó ◽  
Zsófia Bakacsi ◽  
Sándor Koós ◽  
Gabriella Hauk ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Laser Diffraction ◽  
Soil Samples ◽  
Soil Types ◽  
Diffraction Measurement ◽  
Boundary Values ◽  
Soil Physics ◽  
Soil Database ◽  
First Results

In this research we present the first results how can be used laser diffraction measurement in soil physics practice. The main goals are understanding differences of particle size distribution (PSD) measurments, developing converting methods of PSD data of different determinations. In order to realization of this survey a representative soil database of Hungarian soil types was built up. We compared PSDs of 157 soil samples measured with sieve-pipette method (SPM) and laser diffractometer technique (Malvern Mastersizer 2000) (LDM). Soil textural classes were also determined using the USDA texture triangle. We used the clay/silt fraction boundary values (clay < 0.0066 mm; silt: 0.0066 - 0.05 mm) introduced for the LDM data in order to take them comparable to PSD data determined by the SPM: We got higher similarities of clay and silt fractions of the modified size boundary values. For the used dataset correspondence of texture classes derived from SPM and LDM PSD data, however is not higher than 60%.

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