scholarly journals Lung Cancer Mortality and Radon Concentration in a Chronically Exposed Neighborhood in Chihuahua, Mexico: A Geospatial Analysis

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Octavio R. Hinojosa de la Garza ◽  
Luz H. Sanín ◽  
María Elena Montero Cabrera ◽  
Korina Ivette Serrano Ramirez ◽  
Enrique Martínez Meyer ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Spatial Clustering ◽  
Indoor Radon ◽  
Correlation Coefficients ◽  
Lung Cancer Mortality ◽  
Mean Values ◽  
Distance Weighting ◽  
The Mean ◽  
Inverse Distance ◽  
Radon Concentrations

This study correlated lung cancer (LC) mortality with statistical data obtained from government public databases. In order to asses a relationship between LC deaths and radon accumulation in dwellings, indoor radon concentrations were measured with passive detectors randomly distributed in Chihuahua City. Kriging (K) and Inverse-Distance Weighting (IDW) spatial interpolations were carried out. Deaths were georeferenced and Moran’sIcorrelation coefficients were calculated. The mean values (overn=171) of the interpolation of radon concentrations of deceased’s dwellings were 247.8 and 217.1 Bq/m3, for K and IDW, respectively. Through the Moran’sIvalues obtained, correspondingly equal to 0.56 and 0.61, it was evident that LC mortality was directly associated with locations with high levels of radon, considering a stable population for more than 25 years, suggesting spatial clustering of LC deaths due to indoor radon concentrations.

scholarly journals Radiological Assessment of Indoor Radon and Thoron Concentrations and Indoor Radon Map of Dwellings in Mashhad, Iran

2020 ◽  
Vol 18 (1) ◽  
pp. 141
Author(s):  
Mohammademad Adelikhah ◽  
Amin Shahrokhi ◽  
Morteza Imani ◽  
Stanislaw Chalupnik ◽  
Tibor Kovács
Keyword(s):  
Limit Of Detection ◽  
Indoor Radon ◽  
Absolute Error ◽  
Soil Gas ◽  
Indoor Radon Concentration ◽  
Soil Gas Radon ◽  
Distance Weighting ◽  
The City ◽  
Monitoring Devices ◽  
Radon Concentrations

A comprehensive study was carried out to measure indoor radon/thoron concentrations in 78 dwellings and soil-gas radon in the city of Mashhad, Iran during two seasons, using two common radon monitoring devices (NRPB and RADUET). In the winter, indoor radon concentrations measured between 75 ± 11 to 376 ± 24 Bq·m−3 (mean: 150 ± 19 Bq m−3), whereas indoor thoron concentrations ranged from below the Lower Limit of Detection (LLD) to 166 ± 10 Bq·m−3 (mean: 66 ± 8 Bq m−3), while radon and thoron concentrations in summer fell between 50 ± 11 and 305 ± 24 Bq·m−3 (mean 115 ± 18 Bq m−3) and from below the LLD to 122 ± 10 Bq m−3 (mean 48 ± 6 Bq·m−3), respectively. The annual average effective dose was estimated to be 3.7 ± 0.5 mSv yr−1. The soil-gas radon concentrations fell within the range from 1.07 ± 0.28 to 8.02 ± 0.65 kBq·m−3 (mean 3.07 ± 1.09 kBq·m−3). Finally, indoor radon maps were generated by ArcGIS software over a grid of 1 × 1 km2 using three different interpolation techniques. In grid cells where no data was observed, the arithmetic mean was used to predict a mean indoor radon concentration. Accordingly, inverse distance weighting (IDW) was proven to be more suitable for predicting mean indoor radon concentrations due to the lower mean absolute error (MAE) and root mean square error (RMSE). Meanwhile, the radiation health risk due to the residential exposure to radon and indoor gamma radiation exposure was also assessed.

Function–Structure Correlation Studies on Excised Hamster Lungs in Papain-induced Emphysema

1973 ◽  
Vol 51 (9) ◽  
pp. 635-641 ◽  
Author(s):  
P. A. Martorana ◽  
N. W. McKeel ◽  
J. W. Richard ◽  
N. N. Share
Keyword(s):  
Correlation Coefficients ◽  
Histological Evaluation ◽  
Functional Tests ◽  
Elastic Recoil ◽  
Mean Values ◽  
Functional Changes ◽  
High Prediction ◽  
Mean Linear Intercept ◽  
Structure Correlation ◽  
The Mean

Emphysematous lesions induced by a single exposure of hamsters to papain aerosol were evaluated both physiologically (lung elastic recoil) and histologically (mean linear intercept). The extent of the developed lesions was directly related to the concentration of papain employed, and progressed with time following exposure. Histological evaluation was most sensitive for quantitation of minimal lesions; an approximate 20% increase of the mean linear intercept being required for significant functional changes. Maximal mean increase of the mean linear intercept compatible with survival was approximately 75%. Using raw data values, all functional tests exhibited high correlation coefficients (r) with histological evaluation, but prediction efficiencies (r2) were below a practically acceptable value of 75%. However, using group mean values, thereby reducing individual biological variations, higher correlation coefficients as well as high prediction efficiencies were obtained for all functional tests with histological evaluation. In this regard, best prediction efficiencies were obtained for the functional specific static compliance and specific volume at full inflation versus the morphological mean linear intercept.

scholarly journals The first version of the Pan-European Indoor Radon Map

2019 ◽  
Vol 19 (11) ◽  
pp. 2451-2464 ◽  
Author(s):  
Javier Elío ◽  
Giorgia Cinelli ◽  
Peter Bossew ◽  
José Luis Gutiérrez-Villanueva ◽  
Tore Tollefsen ◽  
...  
Keyword(s):  
Uranium Concentration ◽  
Indoor Radon ◽  
Grid Cells ◽  
Indoor Radon Concentration ◽  
Radon Exposure ◽  
Bedrock Geology ◽  
Distance Weighting ◽  
Few Data ◽  
Secondary Variable ◽  
Inverse Distance

Abstract. A hypothetical Pan-European Indoor Radon Map has been developed using summary statistics estimated from 1.2 million indoor radon samples. In this study we have used the arithmetic mean (AM) over grid cells of 10 km × 10 km to predict a mean indoor radon concentration at ground-floor level of buildings in the grid cells where no or few data (N<30) are available. Four interpolation techniques have been tested: inverse distance weighting (IDW), ordinary kriging (OK), collocated cokriging with uranium concentration as a secondary variable (CCK), and regression kriging with topsoil geochemistry and bedrock geology as secondary variables (RK). Cross-validation exercises have been carried out to assess the uncertainties associated with each method. Of the four methods tested, RK has proven to be the best one for predicting mean indoor radon concentrations; and by combining the RK predictions with the AM of the grids with 30 or more measurements, a Pan-European Indoor Radon Map has been produced. This map represents a first step towards a European radon exposure map and, in the future, a radon dose map.

Radon and Lung Cancer in Cornwall and Devon

1993 ◽  
Vol 25 (9) ◽  
pp. 1361-1366 ◽  
Author(s):  
R M Haynes
Keyword(s):  
Lung Cancer ◽  
Cancer Mortality ◽  
Indoor Radon ◽  
Lung Cancer Mortality ◽  
Radiological Protection ◽  
Preventive Action ◽  
Cross Sectional ◽  
Radon Measurements ◽  
The Relationship ◽  
Current Advice

The relationship between average indoor levels of radon and lung cancer mortality in the counties of Cornwall and Devon, England, are investigated. The associations of population density, social-class distribution, and regional smoking prevalence with lung cancer mortality in the local-authority districts of England and Wales were estimated by regression analysis. Low rates of lung cancer in Cornwall and Devon were predicted from the relationship. The differences between observed and predicted mortality in Cornwall and Devon districts were compared with average indoor levels of radon, which varied considerably between districts. Residual variations in lung cancer mortality were not significantly correlated with average indoor radon measurements. The current advice of the National Radiological Protection Board to government is to concentrate radon measurements, remedial action, and preventive action principally on Cornwall and Devon, but cross-sectional geographical data do not support the hypothesis that raised levels of radon indoors in southwest England have an important effect on lung cancer mortality.

scholarly journals A Further Note on Correlation Coefficients Derived From Cumulative Distributions

1972 ◽  
Vol 11 (63) ◽  
pp. 451-454
Author(s):  
David P. Adam
Keyword(s):  
Computer Simulation ◽  
Correlation Coefficients ◽  
Mean Values ◽  
Normal Series ◽  
The Mean

AbstractThis paper elaborates on the note by Andrews and others (1971). It demonstrates that one may obtain any arbitrary value of r between two series of observations by adjusting the mean values of the two series before cumulating them. A computer simulation is used to illustrate the behavior of random Normal series cumulated under varying conditions.

scholarly journals Construction a process to measurement the indoor radon concentration

2013 ◽  
Vol 16 (3) ◽  
pp. 53-60
Author(s):  
Hien Thi To ◽  
Nguyen Thao Nguyen ◽  
Huy Huu Duong
Keyword(s):  
Lung Cancer ◽  
Exposure Time ◽  
Radon Concentration ◽  
Indoor Radon ◽  
Construction Process ◽  
Indoor Radon Concentration ◽  
Radon Exposure ◽  
Indoor Location ◽  
Radon Inhalation ◽  
Radon Concentrations

Radon is a naturally radioactive gas , but it causes lung cancer to humans. The risk of lung cancer due to radiation depends on the amount of radon inhalation and radon exposure time. In Vietnam, radon concentrations are usually determined by RAD7, however RAD7 just showed the immediate values of radon, and have to regularly calibrate it. The construction process to determine the accumulates indoor radon concentration by detector CR- 39 in order to be widely used in the study of environmental pollution, especially the study of health risks of radon for humans and mapping radon pollution. Detector CR - 39 is placed in a 7 cm - plastic holder, and in exposure time, the holders were covered with glass fiber filter paper ∅ 47mm on the bottom of the detector to avoid the exposure of dust. Then it is hung in the indoor location as Vietnam Standard 7889:2008. After 3 months, holders are returned to a laboratory, and CR - 39 will be soaked in 6M NaOH at 700C. Indoor radon concentrations will be proportional to the density traces obtained on CR-39. The study uses an radium 226 source of the NIST (National Institute for Standards and Technology) with the released radon coefficient : f = 0.891 ± 0.015. Results show the calibration factor K is 4.533 ± 0.218 [(Bq.m-3. day)]/(tracks / CR-39)]. Using K factor, we can determine the cumulative indoor radon concentration.

scholarly journals Microbiological quality of shellfish and evaluation of compact dry EC for detecting total coliforms and Escherichia coli

2020 ◽  
Vol 49 (1) ◽  
pp. 32-39 ◽  
Author(s):  
A. Vásquez García ◽  
S.H. Gomes de Sá ◽  
G. de Sousa Silva ◽  
J.E. Mejia Ballesteros ◽  
E. Barbieri ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Conventional Method ◽  
Microbiological Quality ◽  
Correlation Coefficients ◽  
Mean Values ◽  
Total Coliforms ◽  
E Coli ◽  
The Mean

The objective of this study was to evaluate the microbiological quality of oysters and mussels grown in Cananéia, Brazil, by analysing mesophiles, psychrothophic bacteria, moulds and yeasts, Staphylococcus aureus, and Salmonella spp., and to compare the efficiency of Compact Dry EC method and the conventional method for counting of total coliforms and Escherichia coli. The microbial analysis showed that the mean values of mesophilic counts were 3.14±0.81 log CFU g−1 for oysters and 3.92±0.90 for mussels; the mean values of psychrophilic counts were 2.78±0.75 log CFU g−1 for oysters and 3.22±0.75 log CFU g−1 for mussels; the mean values of mould and yeast counts were 3.70±0.58 log CFU g−1 for oysters and 3.33±0.81 log CFU g−1 for mussels. Salmonella spp. did not present positive results, and the maximal count of Staphylococcus aureus was 1.7 log CFU g−1, therefore, within the limits established in the legislation. The correlation coefficients between the Compact Dry EC method and conventional method were >0.87 for total coliform and E. coli counts for both types of shellfish. The data in this study show that the Compact Dry EC method is an acceptable alternative to conventional methods for enumeration of total coliforms and E. coli in shellfish.

scholarly journals Which Plosive Consonant Is More Useful for the Aerodynamic Analysis of Pathologic Voice?

2020 ◽  
Vol 13 (2) ◽  
pp. 179-185
Author(s):  
Yong Tae Hong ◽  
Phan Huu Ngoc Minh ◽  
Ki Hwan Hong
Keyword(s):  
Vocal Fold ◽  
Correlation Coefficients ◽  
Vocal Fold Paralysis ◽  
Unilateral Vocal Fold Paralysis ◽  
Acoustic Parameters ◽  
Mean Values ◽  
Aerodynamic Analysis ◽  
Different Types ◽  
Aerodynamic Parameters ◽  
The Mean

Objectives. Both acoustic and aerodynamic analyses are essential to evaluate the phonetic characteristics of voice pathology. The purpose of the study is to determine the magnitude of their correlation with the different types of bilabial plosive consonants.Methods. A controlled prospective study of 35 patients diagnosed with unilateral vocal fold paralysis was performed. The sustained vowel /a/ and bilabial voiceless consonants were used. Three common acoustic parameters were measured from a sustained vowel /a/ and aerodynamic parameters from a set of syllables /pi/, /p<sup>h</sup>i/, and /p’i/. We determined the correlation coefficients between acoustic and aerodynamic measurements for the bilabial plosive consonants /pi/, /p<sup>h</sup>i/, and /p’i/.Results. The mean values of acoustic parameters were higher than the thresholds of pathology. The mean values of aerodynamic parameters varied according to the types of consonants. The correlation between acoustic and aerodynamic parameters was significantly larger with the consonant /p<sup>h</sup>i/ compared with the consonants /p’/ and /p/. The magnitudes of correlation were higher with the consonant /p<sup>h</sup>i/ compared with the consonants /p’/ and /p/.Conclusion. The plosive consonant /p<sup>h</sup>i/ may represent a more valuable investigative consonant than the consonants /p/ or /p’/ for aerodynamic analysis of voice pathology, especially in patients with unilateral vocal fold paralysis.

scholarly journals Geostatistical Merging of a Single-Polarized X-Band Weather Radar and a Sparse Rain Gauge Network over an Urban Catchment

Atmosphere ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 496 ◽  
Author(s):  
Ibrahim Seck ◽  
Joël Van Baelen
Keyword(s):  
Mean Field ◽  
Radar Data ◽  
Rain Gauge ◽  
Rain Gauge Data ◽  
Rain Gauges ◽  
X Band ◽  
Distance Weighting ◽  
Field Bias ◽  
The Mean ◽  
Inverse Distance

Optimal Quantitative Precipitation Estimation (QPE) of rainfall is crucial to the accuracy of hydrological models, especially over urban catchments. Small-to-medium size towns are often equipped with sparse rain gauge networks that struggle to capture the variability in rainfall over high spatiotemporal resolutions. X-band Local Area Weather Radars (LAWRs) provide a cost-effective solution to meet this challenge. The Clermont Auvergne metropolis monitors precipitation through a network of 13 rain gauges with a temporal resolution of 5 min. 5 additional rain gauges with a 6-minute temporal resolution are available in the region, and are operated by the national weather service Météo-France. The LaMP (Laboratoire de Météorologie Physique) laboratory’s X-band single-polarized weather radar monitors precipitation as well in the region. In this study, three geostatistical interpolation techniques—Ordinary kriging (OK), which was applied to rain gauge data with a variogram inferred from radar data, conditional merging (CM), and kriging with an external drift (KED)—are evaluated and compared through cross-validation. The performance of the inverse distance weighting interpolation technique (IDW), which was applied to rain gauge data only, was investigated as well, in order to evaluate the effect of incorporating radar data on the QPE’s quality. The dataset is comprised of rainfall events that occurred during the seasons of summer 2013 and winter 2015, and is exploited at three temporal resolutions: 5, 30, and 60 min. The investigation of the interpolation techniques performances is carried out for both seasons and for the three temporal resolutions using raw radar data, radar data corrected from attenuation, and the mean field bias, successively. The superiority of the geostatistical techniques compared to the inverse distance weighting method was verified with an average relative improvement of 54% and 31% in terms of bias reduction for kriging with an external drift and conditional merging, respectively (cross-validation). KED and OK performed similarly well, while CM lagged behind in terms of point measurement QPE accuracy, but was the best method in terms of preserving the observations’ variance. The correction schemes had mixed effects on the multivariate geostatistical methods. Indeed, while the attenuation correction improved KED across the board, the mean field bias correction effects were marginal. Both radar data correction schemes resulted in a decrease of the ability of CM to preserve the observations variance, while slightly improving its point measurement QPE accuracy.

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