TY  - JOUR
AU  - Blesić, Suzana
AU  - du Preez, David J.
AU  - Stratimirović, Đorđe
AU  - Ajtić, Jelena
AU  - Ramotsehoa, M. Cynthia
AU  - Allen, Martin W.
AU  - Wright, Caradee
PY  - 2020
UR  - https://vet-erinar.vet.bg.ac.rs/handle/123456789/1805
AB  - Studies of personal solar ultraviolet radiation (pUVR) exposure are important to identify populations at-risk of excess and insufficient exposure given the negative and positive health impacts, respectively, of time spent in the sun. Electronic UVR dosimeters measure personal solar UVR exposure at high frequency intervals generating large datasets. Sophisticated methods are needed to analyze these data. Previously, wavelet transform (WT) analysis was applied to high-frequency personal recordings collected by electronic UVR dosimeters. Those findings showed scaling behavior in the datasets that changed from uncorrelated to long-range correlated with increasing duration of time spent in the sun. We hypothesized that the WT slope would be influenced by the duration of time that a person spends in continuum outside. In this study, we address this hypothesis by using an experimental study approach. We aimed to corroborate this hypothesis and to characterize the extent and nature of influence time a person spends outside has on the shape of statistical functions that we used to analyze individual UVR exposure patterns. Detrended fluctuation analysis (DFA) was applied to personal sun exposure data. We analyzed sun exposure recordings from skiers (on snow) and hikers in Europe, golfers in New Zealand and outdoor workers in South Africa. Results confirmed validity of the DFA superposition rule for assessment of pUVR data and showed that pUVR scaling is determined by personal patterns of exposure on lower scales. We also showed that this dominance ends at the range of time scales comparable to the maximal duration of continuous exposure to solar UVR during the day; in this way the superposition rule can be used to quantify behavioral patterns, particularly accurate if it is determined on WT curves. These findings confirm a novel way in which large datasets of personal UVR data may be analyzed to inform messaging regarding safe sun exposure for human health.
PB  - Academic Press Inc Elsevier Science, San Diego
T2  - Environmental Research
T1  - Characterization of personal solar ultraviolet radiation exposure using detrended fluctuation analysis
VL  - 182
SP  - 108976
DO  - 10.1016/j.envres.2019.108976
ER  - 

@article{
author = "Blesić, Suzana and du Preez, David J. and Stratimirović, Đorđe and Ajtić, Jelena and Ramotsehoa, M. Cynthia and Allen, Martin W. and Wright, Caradee",
year = "2020",
abstract = "Studies of personal solar ultraviolet radiation (pUVR) exposure are important to identify populations at-risk of excess and insufficient exposure given the negative and positive health impacts, respectively, of time spent in the sun. Electronic UVR dosimeters measure personal solar UVR exposure at high frequency intervals generating large datasets. Sophisticated methods are needed to analyze these data. Previously, wavelet transform (WT) analysis was applied to high-frequency personal recordings collected by electronic UVR dosimeters. Those findings showed scaling behavior in the datasets that changed from uncorrelated to long-range correlated with increasing duration of time spent in the sun. We hypothesized that the WT slope would be influenced by the duration of time that a person spends in continuum outside. In this study, we address this hypothesis by using an experimental study approach. We aimed to corroborate this hypothesis and to characterize the extent and nature of influence time a person spends outside has on the shape of statistical functions that we used to analyze individual UVR exposure patterns. Detrended fluctuation analysis (DFA) was applied to personal sun exposure data. We analyzed sun exposure recordings from skiers (on snow) and hikers in Europe, golfers in New Zealand and outdoor workers in South Africa. Results confirmed validity of the DFA superposition rule for assessment of pUVR data and showed that pUVR scaling is determined by personal patterns of exposure on lower scales. We also showed that this dominance ends at the range of time scales comparable to the maximal duration of continuous exposure to solar UVR during the day; in this way the superposition rule can be used to quantify behavioral patterns, particularly accurate if it is determined on WT curves. These findings confirm a novel way in which large datasets of personal UVR data may be analyzed to inform messaging regarding safe sun exposure for human health.",
publisher = "Academic Press Inc Elsevier Science, San Diego",
journal = "Environmental Research",
title = "Characterization of personal solar ultraviolet radiation exposure using detrended fluctuation analysis",
volume = "182",
pages = "108976",
doi = "10.1016/j.envres.2019.108976"
}

Blesić, S., du Preez, D. J., Stratimirović, Đ., Ajtić, J., Ramotsehoa, M. C., Allen, M. W.,& Wright, C.. (2020). Characterization of personal solar ultraviolet radiation exposure using detrended fluctuation analysis. in Environmental Research
Academic Press Inc Elsevier Science, San Diego., 182, 108976.
https://doi.org/10.1016/j.envres.2019.108976

Blesić S, du Preez DJ, Stratimirović Đ, Ajtić J, Ramotsehoa MC, Allen MW, Wright C. Characterization of personal solar ultraviolet radiation exposure using detrended fluctuation analysis. in Environmental Research. 2020;182:108976.
doi:10.1016/j.envres.2019.108976 .

Blesić, Suzana, du Preez, David J., Stratimirović, Đorđe, Ajtić, Jelena, Ramotsehoa, M. Cynthia, Allen, Martin W., Wright, Caradee, "Characterization of personal solar ultraviolet radiation exposure using detrended fluctuation analysis" in Environmental Research, 182 (2020):108976,
https://doi.org/10.1016/j.envres.2019.108976 . .

TY  - JOUR
AU  - du Preez, David J.
AU  - Ajtić, Jelena
AU  - Bencherif, Hassan
AU  - Begue, Nelson
AU  - Cadet, Jean-Maurice
AU  - Wright, Caradee
PY  - 2019
UR  - https://vet-erinar.vet.bg.ac.rs/handle/123456789/1743
AB  - The correlation between solar ultraviolet radiation (UV) and atmospheric ozone is well understood. Decreased stratospheric ozone levels which led to increased solar UV radiation levels at the surface have been recorded. These increased levels of solar UV radiation have potential negative impacts on public health. This study was done to determine whether the break-up of the Antarctic ozone hole has an impact on stratospheric columnar ozone (SCO) and resulting ambient solar UV-B radiation levels at Cape Point, South Africa, over 2007-2016. We investigated the correlations between UV index, calculated from ground-based solar UV-B radiation measurements and satellite-retrieved column ozone data. The strongest anti-correlation on clear-sky days was found at solar zenith angle 25 degrees with exponential fit R-2 values of 0.45 and 0.53 for total ozone column and SCO, respectively. An average radiation amplification factor of 0.59 across all SZAs was calculated for clear-sky days. The MIMOSA-CHIM model showed that the polar vortex had a limited effect on ozone levels. Tropical air masses more frequently affect the study site, and this requires further investigation.
PB  - Copernicus Gesellschaft Mbh, Gottingen
T2  - Annales Geophysicae
T1  - Spring and summer time ozone and solar ultraviolet radiation variations over Cape Point, South Africa
VL  - 37
IS  - 2
SP  - 129
EP  - 141
DO  - 10.5194/angeo-37-129-2019
ER  - 

@article{
author = "du Preez, David J. and Ajtić, Jelena and Bencherif, Hassan and Begue, Nelson and Cadet, Jean-Maurice and Wright, Caradee",
year = "2019",
abstract = "The correlation between solar ultraviolet radiation (UV) and atmospheric ozone is well understood. Decreased stratospheric ozone levels which led to increased solar UV radiation levels at the surface have been recorded. These increased levels of solar UV radiation have potential negative impacts on public health. This study was done to determine whether the break-up of the Antarctic ozone hole has an impact on stratospheric columnar ozone (SCO) and resulting ambient solar UV-B radiation levels at Cape Point, South Africa, over 2007-2016. We investigated the correlations between UV index, calculated from ground-based solar UV-B radiation measurements and satellite-retrieved column ozone data. The strongest anti-correlation on clear-sky days was found at solar zenith angle 25 degrees with exponential fit R-2 values of 0.45 and 0.53 for total ozone column and SCO, respectively. An average radiation amplification factor of 0.59 across all SZAs was calculated for clear-sky days. The MIMOSA-CHIM model showed that the polar vortex had a limited effect on ozone levels. Tropical air masses more frequently affect the study site, and this requires further investigation.",
publisher = "Copernicus Gesellschaft Mbh, Gottingen",
journal = "Annales Geophysicae",
title = "Spring and summer time ozone and solar ultraviolet radiation variations over Cape Point, South Africa",
volume = "37",
number = "2",
pages = "129-141",
doi = "10.5194/angeo-37-129-2019"
}

du Preez, D. J., Ajtić, J., Bencherif, H., Begue, N., Cadet, J.,& Wright, C.. (2019). Spring and summer time ozone and solar ultraviolet radiation variations over Cape Point, South Africa. in Annales Geophysicae
Copernicus Gesellschaft Mbh, Gottingen., 37(2), 129-141.
https://doi.org/10.5194/angeo-37-129-2019

du Preez DJ, Ajtić J, Bencherif H, Begue N, Cadet J, Wright C. Spring and summer time ozone and solar ultraviolet radiation variations over Cape Point, South Africa. in Annales Geophysicae. 2019;37(2):129-141.
doi:10.5194/angeo-37-129-2019 .

du Preez, David J., Ajtić, Jelena, Bencherif, Hassan, Begue, Nelson, Cadet, Jean-Maurice, Wright, Caradee, "Spring and summer time ozone and solar ultraviolet radiation variations over Cape Point, South Africa" in Annales Geophysicae, 37, no. 2 (2019):129-141,
https://doi.org/10.5194/angeo-37-129-2019 . .

TY  - JOUR
AU  - Blesić, Suzana
AU  - Stratimirović, Đorđe
AU  - Ajtić, Jelena
AU  - Wright, Caradee
AU  - Allen, Martin W.
PY  - 2016
UR  - https://vet-erinar.vet.bg.ac.rs/handle/123456789/1426
AB  - Personal sun exposure measurements provide important information to guide the development of sun awareness and disease prevention campaigns. We assess the scaling properties of personal ultraviolet radiation (pUVR) sun exposure measurements using the wavelet transform (WT) spectral analysis to process long-range, high-frequency personal recordings collected by electronic UVR dosimeters designed to measure erythemal UVR exposure. We analysed the sun exposure recordings of school children, farmers, marathon runners and outdoor workers in South Africa, and construction workers and work site supervisors in New Zealand. We found scaling behaviour in all the analysed pUVR data sets. We found that the observed scaling changes from uncorrelated to long-range correlated with increasing duration of sun exposure. Peaks in the WT spectra that we found suggest the existence of characteristic times in sun exposure behaviour that were to some extent universal across our data set. Our study also showed that WT measures enable group classification, as well as distinction between individual UVR exposures, otherwise unattainable by conventional statistical methods.
PB  - Nature Publishing Group, New York
T2  - Journal of Exposure Science and Environmental Epidemiology
T1  - Novel approach to analysing large data sets of personal sun exposure measurements
VL  - 26
IS  - 6
SP  - 613
EP  - 620
DO  - 10.1038/jes.2016.43
ER  - 

@article{
author = "Blesić, Suzana and Stratimirović, Đorđe and Ajtić, Jelena and Wright, Caradee and Allen, Martin W.",
year = "2016",
abstract = "Personal sun exposure measurements provide important information to guide the development of sun awareness and disease prevention campaigns. We assess the scaling properties of personal ultraviolet radiation (pUVR) sun exposure measurements using the wavelet transform (WT) spectral analysis to process long-range, high-frequency personal recordings collected by electronic UVR dosimeters designed to measure erythemal UVR exposure. We analysed the sun exposure recordings of school children, farmers, marathon runners and outdoor workers in South Africa, and construction workers and work site supervisors in New Zealand. We found scaling behaviour in all the analysed pUVR data sets. We found that the observed scaling changes from uncorrelated to long-range correlated with increasing duration of sun exposure. Peaks in the WT spectra that we found suggest the existence of characteristic times in sun exposure behaviour that were to some extent universal across our data set. Our study also showed that WT measures enable group classification, as well as distinction between individual UVR exposures, otherwise unattainable by conventional statistical methods.",
publisher = "Nature Publishing Group, New York",
journal = "Journal of Exposure Science and Environmental Epidemiology",
title = "Novel approach to analysing large data sets of personal sun exposure measurements",
volume = "26",
number = "6",
pages = "613-620",
doi = "10.1038/jes.2016.43"
}

Blesić, S., Stratimirović, Đ., Ajtić, J., Wright, C.,& Allen, M. W.. (2016). Novel approach to analysing large data sets of personal sun exposure measurements. in Journal of Exposure Science and Environmental Epidemiology
Nature Publishing Group, New York., 26(6), 613-620.
https://doi.org/10.1038/jes.2016.43

Blesić S, Stratimirović Đ, Ajtić J, Wright C, Allen MW. Novel approach to analysing large data sets of personal sun exposure measurements. in Journal of Exposure Science and Environmental Epidemiology. 2016;26(6):613-620.
doi:10.1038/jes.2016.43 .

Blesić, Suzana, Stratimirović, Đorđe, Ajtić, Jelena, Wright, Caradee, Allen, Martin W., "Novel approach to analysing large data sets of personal sun exposure measurements" in Journal of Exposure Science and Environmental Epidemiology, 26, no. 6 (2016):613-620,
https://doi.org/10.1038/jes.2016.43 . .