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This study evaluates the effectiveness of self-assessed exposure (SAE) data collection for characterization of hydrogen sulfide (H2S) risks in water and wastewater management, challenging the adequacy of traditional random or campaign sampling strategies. We compared 3 datasets derived from distinct strategies: expert data with activity metadata (A), SAE without metadata (B), and SAE with logbook metadata (C). The findings reveal that standard practices of random sampling (dataset A) fail to capture the sporadic nature of H2S exposure. Instead, SAE methods enhanced by logbook metadata and supported by reliable detection and calibration infrastructure (datasets B and C) are more effective. When assessing risk, particularly peak exposure risks, it is crucial to adopt measures that capture exposure variability, such as the range and standard deviations. This finer assessment is vital where high H2S peaks occur in confined spaces. Risk assessment should incorporate indices that account for peak exposure, utilizing variability measures like range and standard or geometric standard deviation to reflect the actual risk more accurately. For large datasets, a histogram is just as useful as statistical measures. This approach has revealed that not only wastewater workers but also water distribution network workers, can face unexpectedly high H2S levels when accessing confined underground spaces. Our research underscores the need for continuous monitoring with personal electrochemical gas detector alarm systems, particularly in environments with variable and potentially hazardous exposure levels.

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OBJECTIVES: Nordic register data are not collected for research purposes, and various dimensions of working conditions are typically missing in register-based research. One way to address the issue of missing information on the work environment in register data is to utilize a job exposure matrix (JEM). The purpose of this paper is to document and provide access to a Mechanical Job Exposure Matrix (JEM) and a validated Occupational Mechanical Job Exposure Index based on the constructed JEM, allowing researchers to utilize the index in register-based research. The JEM and the Occupational Mechanical Job Exposure Index were created using data from five nationwide Surveys of Living Conditions on work environment conducted in Norway in 2006, 2009, 2013, 2016, and 2019, encompassing a total of 43,977 respondents. The index can be merged to register data using occupational codes (STYRK-98) and gender, which is information collected by the registries. The ultimate aim of constructing the index was to create a comprehensive measure of mechanical job exposures for use in future analyses of Norwegian register data. DATA DESCRIPTION: This paper provides the scripts documenting the construction of the Mechanical Job Exposure Matrix (JEM) and the Occupational Mechanical Job Exposure Index, as well as a data file including the matrix and the index. A script for merging the matrix and index to register data is also provided.

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Background Noise pollution is an emerging global problem that can affect people's well-being and mental and physical health. In India, six percent of people suffer hearing loss, and prolonged exposure leads to irreversible noise-induced hearing loss. Objective To assess the noise levels at selected residential, commercial, industrial, silence zones, traffic junctions, and related noise indices in urban Puducherry and compare them with Central Pollution Control Board (CPCB) standards. Methods The study was conducted using a cross-sectional noise survey based on the 2015 study sites in urban Puducherry using a sound level meter, analyzed the results with limits set by the CPCB standards, and calculated the various noise indices. Results In urban Puducherry, the noise level showing silence zones is more hazardous than industrial, residential, commercial, and traffic junctions. Out of the 36 sites surveyed, 33 locations are above the prescribed daytime limit by CPCB. Conclusions The noise assessment at selected sites in urban Puducherry shows that around 92% of study sites are well above the daytime standards of CPCB, highlighting an urgent need to curb noise levels. The findings revealed that increased noise at study sites could be due to the increased number of vehicles and transportation systems.

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Objective: To establish biological exposure index (BEI) of occupational exposure to arsenic and its inorganic compounds through occupational epidemiology and the regression analysis of internal and external exposure of workers. Methods: In November 2021, 125 workers with occupational exposure to arsenic and its inorganic compounds and 49 office administrators in a non-ferrous metal smelter in Yunnan Province were selected as the exposure group and control group, respectively. Air samples from the workplace of the study subjects on weekdays were collected and arsenic concentrations were determined. Urine samples were collected in end-of-work weekend and high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) was used to detect the levels of trivalent inorganic arsenic (iAs(3+)) , pentavalent inorganic arsenic (iAs(5+)) , monomethyl arsenic (MMA) and dimethyl arsenic (DMA) in urine. The correlations between arsenic concentration in the workplace air and arsenic species in urine of workers were analyzed. Arsenic exposure concentration and the level of urinary arsenic (ΣiAs+MMA+DMA) of workers was analyzed by linear regression and the BEI of arsenic and its inorganic compounds in the workplace was proposed based on the results of micronucleus test. Results: The median of time-weighted average concentration (C(TWA)) of arsenic in the workplace air of the exposure group was 0.0116 mg/m(3), and the over-standard rate was 71.2% (89/125) . The concentrations of iAs(3+), iAs(5+), inorganic arsenic (iAs=ΣiAs(3+)+iAs(5+)) 、MMA、DMA and urinary arsenic in the exposure group were higher than those in the control group at the end of shift, and the differences were statistically significant (P<0.05) . The concentration of arsenic in the workplace air had the strongest correlation with the concentration of urinary arsenic at the end of the shift (r(s)=0.909, P<0.001) . The regression equation was lg (y) =7.662+2.968lg (x) (r=0.821, P<0.05) . According to the occupational exposure limit (OEL) of arsenic in China, the concentration of urinary arsenic in the end-of-work weekend was calculated to be 53.2 µg/L. Combined with the results of micronucleus test, the BEI of occupational exposure to arsenic and its inorganic compounds in the workplace was proposed to be 50 µg/L. Conclusion: The urinary arsenic in the end-of-work weekend can be used as a biomarker of occupational exposure to arsenic, and its BEI is recommended to be 50 µg/L.

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The study evaluated the relationship of various dietary and lifestyle factors with vitamin D status and bone health of adults engaged in office jobs. A total of 100 subjects comprising of 50 males and 50 females (with their willingness to participate) in the age group of 30-50 years were purposively selected for the investigation, who were spending 8 hours in the offices. Results showed that most of the subjects had vitamin D deficit with mean serum vitamin D level as 13.2 ng/ml and 68% were osteopenic. Dietary phytates, sedentary lifestyle, higher body mass index were found to have a deleterious impact on vitamin D status. This silent epidemic needs to be addressed with effective public health initiatives, such as raising awareness about the availability of fortified foods, optimum time, and body surface area for sun exposure.

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The clinical anteroposterior (AP) chest images taken with a mobile radiography system were analyzed in this study to utilize the clinical exposure index (EI) as a patient dose-monitoring tool. The digital imaging and communications in medicine header of 6048 data points exposed under the 90 kVp and 2.5 mAs were extracted using Python for identifying the distribution of clinical EI. Even under the same exposure conditions, the clinical EI distribution was 137.82-4924.38. To determine the cause, the effect of a patient's body shape on EI was confirmed using actual clinical chest AP image data binarized into 0 and 255-pixel values using Python. As a result, the relationship between the direct X-ray area of the chest AP image, the higher the clinical EI, the larger the rate of the direct X-ray area. A conversion equation was also derived to infer entrance surface dose through clinical EI based on the patient thickness. This confirmed the possibility of directly monitoring patient dose through EI without a dosimeter in real-time. Therefore, to use the clinical EI of the mobile radiography system as a patient dose-monitoring tool, the derivation method of clinical EI considers several factors, such as the relationship between patient factors.

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OBJECTIVES: Workers at sewage treatment plants are exposed to a complex mixture of toxins, including hydrogen sulphide (H2S). An issue of concern among sewage workers, is possible negative nervous system effects from low-level H2S exposure. Empirical neuropsychological evidence indicates both that low-dose exposure to H2S exposure affects the nervous system, and the contrary, that such exposure may facilitate nervous system function, since H2S is an endogenously produced central nervous system (CNS) gasotransmitter. The aim of this study is to describe a possible association between the H2S component of the total exposure and long-term effects on neuropsychological motor function among wastewater workers. METHODS: Workers (N = 138) treating wastewater in 6 sewage-treatment plants, or in the sewer net system participated in a cross-sectional study. H2S exposure was expressed in a dichotomous exposure variable defining currently H2S-exposed (N = 112) and unexposed referent workers (N = 26), and a variable defining a job-exposure matrix for long-term total typical workplace H2S exposure. The participants went through neuropsychological tests for hand coordination, reaction time (SRT), and balance, and completed questionnaires. Pearson chi-square test or independent samples t-test was used when comparing the currently H2S-exposed workers with the unexposed control group. Multiple linear regression was used to assess associations between the independent variables age, smoking and exposure variables, and the neuropsychological tests. RESULTS: The analyses indicate increased SRT in the currently H2S-exposed group compared to controls (mean [SD] = 225.8 [29.9] versus 210.7 [26.3] ms, P = 0.019), and an association between increased SRT and current H2S-exposure in the total study sample (ß = 14.7, P = 0.026, R2 = 0.06, P = 0.050). Blindfolded balance testing indicates a nonsignificant trend in the total study sample, of reduced balance in the highest versus lowest H2S total long-term exposure-index group (Sway area [mean {SD}, mm2: 702 [410] versus 581 [278]), and a significant association between total long-term H2S exposure and reduced balance among smokers (Sway area, mm2 [ß = 38.7, P = 0.039], mean sway, mm [ß = 0.3, P = 0.015]). CONCLUSION: The observed trends and associations may be due to exposure peaks in certain work operations and pinpoint the importance of minimizing and avoiding exposure peaks, also when H2S time-weighted average measurements do not exceed an occupational exposure limit of 5 ppm.

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The optimum X-ray tube voltage for chest radiographic examinations remains unclear; hence, the tube voltage varies between medical facilities. An exposure index (EI) was proposed to standardize the parameters for radiographic examinations. However, even if identical EI values are used to examine the same person, organ doses may vary due to differences in tube voltages. In this study, the variation in organ doses between different beam qualities under identical EI values for chest radiographic examinations was investigated using Monte Carlo simulations. A focused anti-scatter grid as well as standard and larger physique-type medical internal radiation dose (MIRD) phantoms were studied under tube voltages of 90, 100, 110, and 120 kVp. The organ doses in the MIRD phantom increased as the X-ray tube voltage decreased, even with identical EI values. The absorbed doses in the lungs of standard and large-sized MIRD phantoms at 90 kVp were 23% and 35% higher than those at 120 kVp, respectively. The doses to organs other than the lung at 90 kVp were also higher than those at 120 kVp. From the perspective of reducing radiation doses, a tube voltage of 120 kVp is considered better for chest examinations compared with a tube voltage of 90 kVp under identical EI values.

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INTRODUCTION: Exposure Index (EI) is incorporated into Digital Radiography (DR) systems to indicate incorrect exposure to enable matching exposure to the desired speed class of operation. However, knowledge of the utilization of EI by radiographers in a low-income country has not been investigated. METHODS: A pre-tested questionnaire designed using Google forms, with open and close-ended questions was shared online with radiographers working with DR systems in public and private health facilities in some cities located in southern Nigeria. The 32-item questionnaire had two parts: Part A focused on socio-demographic characteristics and Part B focused on the respondents' awareness and knowledge of EI in DR systems. A 5-point Likert scale with 5 test items was used to assess the respondents' knowledge of EI. Statistical analyses were conducted using the Statistical Package for Social Sciences (SPSS) version 21.0. The probability value of p < 0.05 was considered statistically significant. RESULTS: About 8.3% of the respondents had good knowledge of EI in DR systems in spite of the awareness level of 24.7%. The absence of the EI concept in DR curriculum for undergraduates, the lack of EI software in DR systems, and equipment training by the vendor engineers were reasons for the low level of knowledge of EI in DR systems. CONCLUSION: There is low awareness and knowledge of EI by radiographers in this study, which suggests the need to maximize the benefits of EI concepts by ensuring its integration into clinical radiography practice and curriculum for undergraduates program, to improve knowledge, awareness, and practice in DR.

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BACKGROUND: Digital radiography (DR) still presents many challenges and could have complex imaging acquisition and processing patterns in a clinical practice hindering quality standardization. PURPOSE: This technical note aims to report the 4-year experience with utilizing a custom DICOM metadata analytics program in clinical DR at a large institution. METHODS: Thirty-eight DR systems of three vendors at multiple locations were configured to automatically send clinical DICOM images to a DICOM receiver. A suite of custom MATLAB programs was established to extract and store public and private header data weekly. Specific use cases are provided for systematic image acquisition investigation, image processing harmonization, exposure index (EI) longitudinal monitoring and EI target optimization. RESULTS: For systematic acquisition investigation, an example of adult lumbar spine exam analysis was provided with statistics on manual acquisition versus the use of automatic exposure control (AEC, including AEC dose level, active cell, and backup timer), grid usage, and collimation for various projections. For processing harmonization, up to 12.6% of protocols were revealed to have processing parameter differences in an example of a mobile radiography fleet. In addition, inconsistent use of a post-acquisition image size function was also demonstrated, which resulted in anatomy size display variations. Bimonthly monitoring of median EI values showed expected trends, including changes after an AEC dose level adjustment for adult posterior-anterior chest imaging on a scanner system. An example of adult axillary shoulder EI target refinement was shared using the median value, eµ , based on the lognormal EI data distribution after parsing down to acquisitions with appropriate techniques. CONCLUSIONS: This analytics program enables systematic analysis of image acquisition and processing details. The information provides invaluable insights into real practice patterns, which can support data-driven quality standardization and optimization.

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Rapid anthropogenic climate change is driving threatened biodiversity one step closer to extinction. Effects on native biodiversity are determined by an interplay between species' exposure to climate change and their specific ecological and life-history characteristics that render them even more susceptible. Impacts on biodiversity have already been reported, however, a systematic risk evaluation of threatened marine populations is lacking. Here, we employ a trait-based approach to assess the risk of 90 threatened marine Mediterranean species to climate change, combining species' exposure to increased sea temperature and intrinsic vulnerability. One-quarter of the threatened marine biodiversity of the Mediterranean Sea is predicted to be under elevated levels of climate risk, with various traits identified as key vulnerability traits. High-risk taxa including sea turtles, marine mammals, Anthozoa and Chondrichthyes are highlighted. Climate risk, vulnerability and exposure hotspots are distributed along the Western Mediterranean, Alboran, Aegean, and Adriatic Seas. At each Mediterranean marine ecoregion, 21%-31% of their threatened species have high climate risk. All Mediterranean marine protected areas host threatened species with high risk to climate change, with 90% having a minimum of 4 up to 19 species of high climate risk, making the objective of a climate-smart conservation strategy a crucial task for immediate planning and action. Our findings aspire to offer new insights for systematic, spatially strategic planning and prioritization of vulnerable marine life in the face of accelerating climate change.

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Perfluorooctanoic acid (PFOA) in environmental matrices is increasingly being studied due to its environmental persistence, global occurrence, bioaccumulation, and associated human health risks. Some indoor environments can significantly impact the health of occupants due to pollutants in indoor air and household dust. To investigate the potential exposure of individuals to PFOA in specific confined environments, this study reports an analytical method and results concerning the determination of PFOA in household dust, used as a passive sampler. To the best of our knowledge, this paper represents one of the first studies concerning PFOA concentrations in indoor dust collected in the south of Italy, within the European region. A total of twenty-three dust samples were collected from two different areas of Sicily (Palermo and Milena), extracted, and analyzed by an UHPLC-QTOF-MS/MS system. Finally, PFOA exposure was estimated using a new index (Indoor PFOA Exposure Index, IPEX) that incorporates the PFOA levels in dust, exposure time, and the correlation between the PFOA in dust and blood. It was then compared across four different exposure groups, revealing that PFOA exposure for people working in chemistry laboratories was evaluated to be ten times higher than the exposure for homemakers.

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Arsenic is a common metal-like element. Drinking arsenic-containing water and occupational exposure to arsenic are the main ways exposure to arsenic for population. Long-term exposure to arsenic can cause various organs dysfunction and cancer. After entering the body, inorganic arsenic is mainly methylated into monomethyl arsenic and dimethyl arsenic in the liver. Only a small part of inorganic arsenic is metabolized in the kidneys and lungs, and finally the metabolites of arsenic are excreted in the urine. understanding the biological characteristics of arsenic absorption, metabolism, and distribution in the body and formulating biological indicators related to occupational exposure to arsenic and can provide a scientific basis for the prevention and treatment of arsenic-related diseases. This article will review the biological monitoring indicators of occupational exposure to arsenic and the metabolic process of arsenic in the body.

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BACKGROUND: The overall aim of this study was to examine essential aspects of reliability and validity of a constructed Occupational Mechanical Job Exposure Index for use in analyses of Norwegian register data.  METHODS: We utilized data from the Norwegian nationwide Survey of Living Conditions on work environment in 2006, 2009, 2013, 2016 and 2019. Occupations were classified on a 4-digit level based on the Norwegian version of the International Standard Classification of Occupations (ISCO-88). We constructed a 4-digit correspondence table between the occupational codes used in the 2006 and 2009 surveys (STYRK-98) and the codes used in 2013, 2016 and 2019 (STYRK-08). The mechanical exposures were collected by Statistics Norway using telephone interviews. As for reliability, we examined the agreement between the individual- and the occupational-based mechanical exposures using Cohen's kappa, sensitivity and specificity measures. Construct, concurrent and predictive validity pertaining to the Occupational Mechanical Job Exposure Index were analysed using both survey data and nationwide register data. RESULTS: The analysis shows a fair-to-moderate overlap between occupational-based mechanical exposures and the individually reported exposures. Construct validity of the Occupational Mechanical Job Exposure Index, as estimated by a confirmatory factor analysis using the occupational-based mechanical exposures, showed that the 8 exposures formed one underlying factor. When assessing the concurrent value of the Occupational Mechanical Job Exposure Index to the index based on the individual reported exposures, the occupational mechanical index showed lower and reproducible associations with lower back pain for both men and women. For long-term sick leave, the occupational mechanical index showed higher and reproducible associations for both genders. As for predictive validity, the register data analysis shows that the occupational mechanical index was associated with disability and a higher number of long-term sickness benefits periods for both men and women. For men the index also predicted higher mortality. CONCLUSION: Our tests of reliability and validity of the Occupational Mechanical Job Exposure Index indicate that the index overall has acceptable statistical properties and will be useful in analyses of Norwegian register data where individual information on these types of exposures is missing.

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Aim: The exposure index (EI) is used in routine quality control (QC) tests performed in the radiographic equipment installed in our hospitals. This study aimed at investigating the factors affecting the calculation of EI in QC and clinical images, and the implementation of target EI (EIT) and deviation index (DI) in clinical practice. Methods: The EI is 100 times the incident air kerma (IAK) in µGy on the image receptor, using the RQA-5 X-ray beam quality. Conformance to this relationship was investigated in QC images and clinical images acquired using anthropomorphic phantom body parts and different examination protocols, tube potential settings and radiation field sizes. Furthermore, a survey on EIT and DI data from clinical images was performed. Results: Though automatic exposure control (AEC) systems have been adjusted for an IAK of 2.5 µGy, for most anthropomorphic phantom images the EIs were far from 250, depending on the manufacturer, the anatomy imaged, and the examination protocol. Regarding the survey results, DI calculation was feasible in only 38 % of the systems, since for the rest EIT values have not been set. However, the rationale based on which EIT have been selected is unclear. Some systems use only one while others many different EIT values. Conclusion: Before using EI for quality control of clinical images image all receptors and AEC systems should be properly calibrated. Then, the methodology of selecting appropriate EIT should be refined, since the EI calculation may vary, depending on the manufacturer, the anatomy imaged, and the examination protocol.

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The amount of agricultural drought vulnerability in an underdeveloped rain-fed agro-based economy at the local, regional, and national level is most prominent factor for measurement. The desiccation of rain in agricultural sector becomes apprehensive to intercontinental food supply chain. So, adequate investigation and development of sustainable agricultural methodology are key factors to sustain the food security of a territory. In this research, delineation of agricultural drought vulnerability (ADV) status has been carried out by multidimensional mixed-method index approach using remote sensing and geographic information system. An integrated three-dimensional model is utilized to enrich this study. The three indices of this model include exposure index (EI), sensitivity index (SI), and adaptive capacity index (ACI). The ACI has been constructed by combining the environmental adaptive capacity (EAC), social adaptive capacity (SAC), and economic adaptive capacity (EcAC) index. The 40 parameters for ADV modeling are picked up by analyzing meteorological, geo-environmental, social, and remote sensing data. There are six exposure parameters, seven sensitivity parameters, twelve environmental adaptive capacity parameters, six social adaptive capacity parameters, and nine economic adaptive capacity parameters. Each index has been computed by assigning the weights based on their relative importance by using the analytic hierarchy process (AHP) approach. Final results were classified into five vulnerability zones, e.g., very low, low, moderate, high, and very high covering an area 362.32 km2, 186.68 km2, 568.69 km2, 547.05 km2, and 266.89 km2 respectively. Results have been validated with long-term Aman paddy yield data (2004 to 2014) through the yield anomaly index (YAI). Finally, the model ADV is a good model fit (R square = 0.894) and all the relationships were found significant, when SI, EI, and ACI are considered its predictors. While SI (B = 0.391, p < 0.001) and EI (B = 0.223, p < 0.001) are positively associated with ADV, ACI is negatively associated with ADV (B = - 0.721, p < 0.001). This regional agricultural drought vulnerability model can be useful to identify drought-responsive areas and improve drought mitigation measures.

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Background: Though, smoking is the leading cause of chronic obstructive pulmonary disease worldwide, the household air pollution due to use of solid biomass fuel is considered as a major risk factor for the development of obstructive lung disease. The aim of the study was to assess the effect of solid biomass fuel exposure on lung functions in non-smoking female population. Methods: A hospital based, descriptive cross sectional study was carried out among 140 non-smoking female patients aged 40 or more and who had been exposed to solid biomass fuel. These patients underwent spirometry to assess their lung function and were classified as obstructive, restrictive or mixed. Modified medical research council (mMRC) dyspnoea scale for symptom assessment, 6-minute walk test (6 MWT) to determine the exercise capacity and Cumulative exposure index to assess the duration of exposure were also done. Results: All 140 (100%) patients having abnormal lung function, 4 (2.86%) had restrictive pattern, 5 (3.57%) had mixed pattern and 131 (93.57%) had obstructive pattern. Of 131 patients having obstructive pattern, 11 had mild obstruction, 49 had moderate obstruction, 39 had severe obstruction and 32 had very severe obstruction. Most commonly used biomass fuel was wood (43.57%). All the patients had shortness of breath, whereas cough was present in only 35.71% cases. 77 (55%) patients presented with a dyspnoea of mMRC grade 3 and above. Conclusion: Cumulative exposure index for solid biomass fuel is directly proportional to the severity of lung impairment as well as the symptom severity.

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In many digital X-ray imaging systems, although air kerma on a surface of each detector is used, a standardized dose index called an exposure index (EI) has been proposed by the IEC, which is expected to be utilized for dose management. In clinical practices, EI is effectively utilized using a deviation index (DI), which is a deviation between a target EI (EIT) set for each imaging region and an EIT of the acquired image. However, an important issue in clinical uses of EI is a suppression of excessive doses. It is difficult to achieve a reliable reduction in exposure doses by indicating DI. In this study, physical image characteristics of detectors, visual detectability by charts, and observer experiments using a chest phantom were examined to determine upper (DImax) and lower (DImin) limits of the EIT and DI to achieve a reliable dose reduction in chest examinations. As the result, the tolerance ranges indicated by DImax and DImin, which were set based on the results of physical and visual evaluations, proved to be almost consistent with the distribution of EI values in 735 clinical images taken with a photo-timer control in real clinical practices.

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The number of occupants in a space influences the risk of far-field airborne transmission of SARS-CoV-2 because the likelihood of having infectious and susceptible people both correlate with the number of occupants. This paper explores the relationship between occupancy and the probability of infection, and how this affects an individual person and a population of people. Mass-balance and dose-response models determine far-field transmission risks for an individual person and a population of people after sub-dividing a large reference space into 10 identical comparator spaces. For a single infected person, the dose received by an individual person in the comparator space is 10 times higher because the equivalent ventilation rate per infected person is lower when the per capita ventilation rate is preserved. However, accounting for population dispersion, such as the community prevalence of the virus, the probability of an infected person being present and uncertainty in their viral load, shows the transmission probability increases with occupancy and the reference space has a higher transmission risk. Also, far-field transmission is likely to be a rare event that requires a high emission rate, and there are a set of Goldilocks conditions that are just right when equivalent ventilation is effective at mitigating against transmission. These conditions depend on the viral load, because when they are very high or low, equivalent ventilation has little effect on transmission risk. Nevertheless, resilient buildings should deliver the equivalent ventilation rate required by standards as minimum.

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Indoor air pollution from the combustion of biomass fuel and associated health risks is a critical issue in developing countries. Concentrations of PM2.5 and PM10 are measured in Birbhum, West Bengal, during 2017-2018. PM2.5-bound elemental concentrations of twelve metals are determined in rural kitchens. The results showed higher toxicological risks in BMF (1.15) than the LPG users (0.14). The risk of non-carcinogenic exposure related with dermal contact and ingestion was observed in the acceptable limits (HQ < 1) for all age groups, and the risk associated with inhalation exposure from Cr, Ni, As, and Mn exceeded the acceptable limit. Results also suggest that carcinogenic risks from ingestion and dermal contact are within the acceptable limit (1 × 10-4-1 × 10-6) except Cr and As which were found to exceed the range. The deposition flux (Dφ) for multiple metals in the head airway region, tracheobronchial region, and alveolar regions was found to be higher in teenagers as compared to other groups, whereas the value was lower in infants. Further, it was notified from the Dφ that the metals could pass through the head airways and harm the tracheobronchial tree and alveolar region, increasing the risk of human health.

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