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BackgroundThe 6-Minute Walk Test (6MWT) is a standardised method routinely used to screen for and monitor interstitiel lunge disease and/or pulmonary arterial hypertension in patients with systemic sclerosis (SSc). Studies shows that esaturations during the 6MWT are associated with severity of pulmonary manifestations in patients with SSc [1]. Digital sensors are commonly used to measure peripheral oxygen saturation (SpO2) during the 6MWT. However, digital-based sensors may have important limitations in patients with SSc due to disease-related microangiopathy, Raynaud's phenomenon, sclerodactyly and motion artifacts during the 6MWT [2]. Sensors located at more central body positions may therefore be more accurate as these as less prone to Raynaud attacks.ObjectivesTo determine the validity and re-test reliability of peripheral oxygen saturation measured at the finger, forehead, and ear during the 6MWT in patients with SSc.Methods82 patients with SSc had an arterial line placed while performing the 6MWT. Peripheral oxygen saturation was simultaneously measured by finger, forehead, and earlobe sensors and compared to the arterial oxygen saturation (SaO2) measured before and after the 6MWT. 40 patients repeated the 6MWT one week later. We used Bland-Altman plots to display the agreement between SpO2 and SaO2, and between the minimal SpO2 (minSpO2) one week apart. The intraclass correlation coefficient (ICC, 95% confidence interval 95% CI]) for repeated measurement of minSpO2 was calculated.ResultsThe mean difference (SpO2 - SaO2, ± standard deviation [SD]) after the 6MWT was –3.3% (±4.82), 0.15% (±1.55), and 1.36% (±1.93) for the finger, forehead, and earlobe, respectively (Table 1).The finger minSpO2 also demonstrated the poorest re-test reliability: The mean difference in minSpO2 (visit2-visit1, ±SD) was 1.28% (±5.3), 0.74% (±4.36) and –1.10% (±2.87),). The ICC (95% CI) showed good agreement using the ear and forehead probe (ICCear = 0.89 [0.80;0.94];ICCforehead = 0.88 [0.60;0.87]), while a modest reliability was found using the finger probe (ICCfinger = 0.65 [0.43;0.80]).ConclusionPeripheral oxygen saturation should be measured using either the earlobe or forehead during the 6MWT in patients with SSc.References[1]Villalba, W. O. et al. Six-minute walk test for the evaluation of pulmonary disease severity in scleroderma patients. Chest 131, 217–222 (2007).[2]Pathania, Y. S. Alternatives for erroneous finger probe pulse oximetry in systemic sclerosis patients during COVID-19 pandemic. Rheumatol. Int. 41, 2243–2244 (2021).Table 1.Validity and re-test reliability of peripheral oxygen during the 6MWT (n= 82)Finger probeForehead probeEar probeMean difference SpO2 - SaO2 Mean difference pre-test (+/-SD)–0.68% (±1.88)0.13% (±1.26)1.54% (±0.69) Mean difference post--test (+/-SD)–3.30% (±4.82)0.15% (±1.55)1.36% (±1.93)Mean difference of the minSpO2 (visit2-visit1) Mean difference (±SD)1.28% (±5.3)0.74% (±4.36)1.10% (±2.87)Abbreviations: SpO2, Peripheral oxygen saturation;SaO2, Arterial oxygen saturation;SD, Standard deviation.Acknowledgements:NIL.Disclosure of InterestsAmanda Lynggaard Riis: None declared, Esben Naeser Paid instructor for: Boehringer Ingelheim Denmark, Katja Thorup Aaen: None declared, Henrik Hovgaard: None declared, Peter Juhl-Olsen: None declared, Elisabeth Bendstrup Speakers bureau: Hoffman-la-Roche.Boehringer Ingelheim.Glaxo Smith Kleine.Daichii Sankyo, Klaus Soendergaard Speakers bureau: Boehringer Ingelheim, Consultant of: Boehringer Ingelheim, Grant/research support from: Boehringer Ingelheim.
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In December 2019, several cases of pneumonia caused by SARS-CoV-2 were identified in the city of Wuhan (China), which was declared by the WHO as a pandemic in March 2020 because it caused enormous problems to public health due to its rapid transmission of contagion. Being an uncontrolled case, precautions were taken all over the world to moderate the coronavirus that undoubtedly was very deadly for any person, presenting several symptoms, among them we have fever as a common symptom. A biosecurity measure that is frequently used is the taking of temperature with an infrared thermometer, which is not well seen by some specialists due to the error they present, therefore, it would not represent a safe measurement. In view of this problem, in this article a thermal image processing system was made for the measurement of body temperature by means of a drone to obtain the value of body temperature accurately, being able to be implemented anywhere, where it is intended to make such measurement, helping to combat the spread of the virus that currently continues to affect many people. Through the development of the system, the tests were conducted with various people, obtaining a more accurate measurement of body temperature with an efficiency of 98.46% at 1.45 m between the drone and the person, in such a way that if it presents a body temperature higher than 38° C it could be infected with COVID-19. © 2023 IEEE.
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Purpose: Organic food consumption decreases the risk of becoming obese or overweight. This study intends to see the influence of customer perceived value, COVID-19 fear, food neophobia, effort and natural content on the intention to purchase organic food (IPOF) that leads to the actual purchase of organic food (APOF). Moreover, organic food availability is a moderator between IPOF and APOF. Design/methodology/approach: PLS-SEM is used for hypothesis testing. A purposive sampling technique was followed to gather data from organic food consumers in Lahore, Gujranwala and Islamabad and a total of 479 questionnaires were part of the analysis. Findings The outcomes show that customer perceived value, effort and natural content is positively related to IPOF. Despite this, COVID-19 fear and food neophobia are negatively associated with IPOF. IPOF and organic food availability are positively related to APOF. Finally, organic food availability significantly moderated between IPOF and APOF. Practical implications: This study outcome reveals that companies of organic food can recognize customer perceived value, COVID-19 fear, food neophobia, effort, natural content and organic food availability in their decision-making if they determine the actual purchase of organic food. This study offers a valuable policy to companies of organic food to enhance customer's behavior in purchasing organic food in Pakistan. Besides, practitioners and academicians can benefit from this study finding. Originality/value: This initial research integrates customer perceived value, COVID-19 fear, food neophobia, effort, natural content, IPOF and organic food availability to determine APOF in the COVID-19 pandemic. Moreover, consumption value theory is followed to develop the framework.
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Background and purpose: The present study investigated the effect of six weeks of endurance and resistance training on pulmonary indices, physical performance, and quality of life in COVID-19 patients after discharge from hospital. Materials and methods: Thirty six patients with COVID-19 (mean age: 38.76+or-0.98 years, mean weight: 81.86+or-2.88 kg) were selected. At the beginning and end of the study, pulmonary (FEV1, FVC, FEV1/FVC, and MVV), physical (6-minute walk test), quality of life (SF-36), and anthropometry tests were performed. The patients were divided into three groups: Endurance training (45 minutes at 60-75% estimated HR), Resistance training (45 minutes at 40-70% of I-RM), and controls. The intervention was conducted for 6 weeks (3 sessions). One-way ANOVA test was used for statistical analysis. Results: Findings indicated a significant increase in FEV1 (P=0.029), FVC (P=0.047), FEV1/FVC (P=0.043) in the endurance training group compared to the control group, while difference was observed in MVV (P=0.041) and FEV1/FVC (P=0.022) between endurance training and resistance training groups. The 6-minute test distance increased in the endurance training (P=0.0001) and resistance training (P=0.001) groups compared to the control group, but no difference was observed between the training groups (P=0.48). Endurance and resistance training programs induced significant improvements in physical performance (P=0.024 and P=0.09, respectively) and general health (P=0.022 and P=0.015, respectively) dimensions compared to the control group. Conclusion: Moderate-intensity endurance training can improve pulmonary function, physical performance, and quality of life in patients with COVID-19 after discharge from hospital and can be used in rehabilitation programs of these patients.
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The COVID‐19 pandemic resulted in a widespread lockdown during the spring of 2020. Measurements collected on a light rail system in the Salt Lake Valley (SLV), combined with observations from the Utah Urban Carbon Dioxide Network observed a notable decrease in urban CO2 concentrations during the spring of 2020 relative to previous years. These decreases coincided with a ∼30% reduction in average traffic volume. CO2 measurements across the SLV were used within a Bayesian inverse model to spatially allocate anthropogenic emission reductions for the first COVID‐19 lockdown. The inverse model was first used to constrain anthropogenic emissions for the previous year (2019) to provide the best possible estimate of emissions for 2020, before accounting for emission reductions observed during the COVID‐19 lockdown. The posterior emissions for 2019 were then used as the prior emission estimate for the 2020 COVID‐19 lockdown analysis. Results from the inverse analysis suggest that the SLV observed a 20% decrease in afternoon CO2 emissions from March to April 2020 (−90.5 tC hr−1). The largest reductions in CO2 emissions were centered over the northern part of the valley (downtown Salt Lake City), near major roadways, and potentially at industrial point sources. These results demonstrate that CO2 monitoring networks can track reductions in CO2 emissions even in medium‐sized cities like Salt Lake City.Alternate :Plain Language SummaryHigh‐density measurements of CO2 were combined with a statistical model to estimate emission reductions across Salt Lake City during the COVID‐19 lockdown. Reduced traffic throughout the COVID‐19 lockdown was likely the primary driver behind lower CO2 emissions in Salt Lake City. There was also evidence that industrial‐based emission sources may of had an observable decrease in CO2 emissions during the lockdown. Finally, this analysis suggests that high‐density CO2 monitoring networks could be used to track progress toward decarbonization in the future.
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The unprecedented lockdown of human activities during the COVID-19 pandemic has significantly influenced social life in China. However, understanding the impact of this unique event on the emissions of different species is still insufficient, prohibiting the proper assessment of the environmental impacts of COVID-19 restrictions. Here we developed a multi-air-pollutant inversion system to simultaneously estimate the emissions of NOx, SO2, CO, PM2.5 and PM10 in China during COVID-19 restrictions with high temporal (daily) and horizontal (15 km) resolutions. Subsequently, contributions of emission changes versus meteorological variations during the COVID-19 lockdown were separated and quantified. The results demonstrated that the inversion system effectively reproduced the actual emission variations in multi-air pollutants in China during different periods of COVID-19 lockdown, which indicate that the lockdown is largely a nationwide road traffic control measure with NOx emissions decreasing substantially by ∼40 %. However, emissions of other air pollutants were found to only decrease by∼10% because power generation and heavy industrial processes were not halted during lockdown, and residential activities may actually have increased due to the stay-at-home orders. Consequently, although obvious reductions of PM2.5 concentrations occurred over the North China Plain (NCP) during the lockdown period, the emission change only accounted for 8.6 % of PM2.5 reductions and even led to substantial increases in O3. The meteorological variation instead dominated the changes in PM2.5 concentrations over the NCP, which contributed 90 % of the PM2.5 reductions over most parts of the NCP region. Meanwhile, our results suggest that the local stagnant meteorological conditions, together with inefficient reductions of PM2.5 emissions, were the main drivers of the unexpected PM2.5 pollution in Beijing during the lockdown period. These results highlighted that traffic control as a separate pollution control measure has limited effects on the coordinated control of O3 and PM2.5 concentrations under current complex air pollution conditions in China. More comprehensive and balanced regulations for multiple precursors from different sectors are required to address O3 and PM2.5 pollution in China.
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Percentage of body fat, age, weight, height, and 14 circumference measurements (e.g., waist) are given for 184 women aged 18–25. Body fat, one measure of health, was accurately determined by an underwater weighing technique which requires special equipment and training of the individuals conducting the process. Modeling body fat percentage using multiple regression provides a convenient method of estimating body fat percentage using measures collected using only a measuring tape and a scale. This dataset can be used to show students the utility of multiple regression and to provide practice in model building.
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Purpose: The nutritional and anthropometric status can be essential in determining their immune response to vaccines. The purpose of this paper was to investigate the association between diet quality and anthropometric indices with the side effects of the Pfizer-BioNTech COVID-19 vaccine and the SARS-CoV-2 immunoglobulin G titer among Kurdish adults. Design/methodology/approach: This cross-sectional survey-based study was conducted between December 2021 and February 2022. This paper included data on 115 adults, 20-89 years old, from the Kurdistan region. Dietary information was collected using a short food frequency questionnaire, and diet quality was assessed using a plant-based healthy diet score. A blood test was performed to measure the SARS-CoV-2 immunoglobin G (IgG) titer after the vaccination's first and second doses. Findings: Overweight and obese subjects reported more local pain, myalgia, headache, local bruising and local reactions after receiving the first dose of the vaccine (p = 0.04). People on a less healthy diet reported more local pain, myalgia and headache (p = 0.04) and more local bruising and reactions (p = 0.01) after receiving the second dose of the vaccine. On the other hand, the authors observed that those with healthy dietary habits had more IgG titer after the first and second doses of vaccination than those with less healthy dietary habits (p = 0.001). Originality/valueThe results showed that participants with a healthy diet and normal weight status had fewer side effects of the Pfizer-BioNTech COVID-19 vaccine than obese people and those with a less healthy diet.
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In this paper we report two applications of a subcategory of air cleaning devices based on soft ionization that do not cause molecular fragmentation. A system that includes two unipolar ionizing modules has been used to simultaneously produce positive and negative ions in the air. In one set of experiments a large chamber (28 m3) was used to study the effect of ions on reducing PM1.0 particles produced by a research grade calibrated cigarette. The data presented in this paper were obtained using a carbon-brush-based bipolar ionizer and a MERV 10 filter with electret media in a recirculating HVAC system. Significant improvement in removal rate of fine and ultrafine particles was achieved when using the bipolar ionizer in conjunction with the MERV 10 filter. The second set of experiments were conducted using a 36 m3 chamber, following BSL-3 standards, to study the effect of ions on aerosolized SARS-CoV-2. Results of these investigations reveal the inactivation rate of SARS-CoV-2 are enhanced when ions are introduced in the air;inactivation rates were increased by more than 60%and 90%for ion densities of 10,000/cc and 18,000/cc. IEEE
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Purpose: The pandemic of COVID-19 led to considerable challenges with respect to people's health, dietary behavior and satisfaction with life. This study aims to investigate perceived stress levels, in relation to diet quality and life satisfaction in Greek adults, during the COVID-19 lockdown. Design/methodology/approach: This is a cross-sectional study which took place in Greece in the course of the strict lockdown period, in the third COVID-19 wave. A sample of 2,029 adults aged 18 years and above participated in an online survey. The questionnaire consisted of questions on sociodemographic and anthropometric characteristics. The Perceived Stress Scale, the Satisfaction with Life Scale and the Mediterranean Diet Assessment Tool were also used. Findings: Linear regression has shown that women (p < 0.0001), younger individuals (p < 0.0001), obese individuals (p = 0.047), those with lower levels of satisfaction with life (p < 0.0001) and lower adherence to Mediterranean diet (p = 0.0001) were positively associated with higher levels of stress. Originality/value: To the best of the authors' knowledge, this is the first study conducted in Greece aiming at investigating concurrently, levels of perceived stress, with respect to levels of satisfaction with life and diet quality in adults, during the lockdown period of the COVID-19 pandemic.
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The present study is related to the problem associated with student assessment with online examinations at higher educational institutes (HEIs). With the current COVID-19 outbreak, the majority of educational institutes are conducting online examinations to assess their students, where there would always be a chance that the students go for malpractice. It is difficult to set a question paper for any technical course with great novelty. Under these circumstances, safeguarding academic integrity has become a challenge for HEIs. This study is aimed at improving the quality of questions for online exams to increase the accountability of HEIs by proper evaluation of their students. A detailed procedure with suggestions for setting the questions for technical courses, in the format of assertion and reason, matching, multiple select types, etc., has been discussed with adequate examples. It deals with a strategy for ensuring that all the students are held to the standards that are reflected in their grades. The proposed evaluation method has been implemented on a test batch and presented the results along with a comparison with that of traditional question papers. It is witnessed that there is a simultaneous enhancement of students'learning as an additional benefit of implementing the proposed learning-oriented assessment method. IEEE
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OBJECTIVES: Previous studies identified a number of diseases were associated with 2019 coronavirus disease (COVID-19). However, the associations between these diseases related viral infections and COVID-19 remains unknown now. METHODS: In this study, we utilized single nucleotide polymorphisms (SNPs) related to COVID-19 from genome-wide association study (GWAS) and individual-level genotype data from the UK biobank to calculate polygenic risk scores (PRS) of 487,409 subjects for eight COVID-19 clinical phenotypes. Then, multiple logistic regression models were established to assess the correlation between serological measurements (positive/negative) of 25 viruses and the PRS of eight COVID-19 clinical phenotypes. And we performed stratified analyses by age and gender. RESULTS: In whole population, we identified 12 viruses associated with the PRS of COVID-19 clinical phenotypes, such as VZV seropositivity for Varicella Zoster Virus (Unscreened/Exposed_Negative: ß = 0.1361, P = 0.0142; Hospitalized/Unscreened: ß = 0.1167, P = 0.0385) and MCV seropositivity for Merkel Cell Polyomavirus (Unscreened/Exposed_Negative: ß = -0.0614, P = 0.0478). After age stratification, we identified seven viruses associated with the PRS of eight COVID-19 clinical phenotypes. After gender stratification, we identified five viruses associated with the PRS of eight COVID-19 clinical phenotypes in the women group. CONCLUSION: Our study findings suggest that the genetic susceptibility to different COVID-19 clinical phenotypes is associated with the infection status of various common viruses.
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This study combines particle measurements and acoustic measurements to study aerosols generated in breathing, speaking, singing and coughing. Particle measurements are carried out using a portable measurement chamber designed specially for the study. Acoustic measurements of voice production are conduced to standardize measurements in human aerosol emission and to reveal possible reasons for the individual differences in particle generation. Understanding mechanisms of human aerosol generation is important in trying to understand how the airborne transmission of pathogens takes place and furthermore in assessing how to minimize the risk of transmission. The results can be used in the context of all airborne diseases. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.
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Background: COVID-19 patients may experience lon-lasting symptoms from weeks to even months. Aim: To evaluate long-term cognitive impairment based on the severity of symptoms of COVID-19 infection in a primary health system setting. Material and methods: From a database of 363 patients, 83 cases aged 47 +or- 15 years, (58% females) were selected from June to August 2020. In patients who survived the virus, 24 infection-related symptoms were collected to create three severity clusters (mild, moderate, and severe). The follow-up time was at least seven months. Comparing the first two clusters with the severe cluster, the existence of brain fog and risk factors (obesity, hypertension, diabetes, chronic lung disease, and hypothyroidism) were analyzed. Results: Thirty-one patients (37%) had persistent symptoms lasting up to 240 days. Fifty-one patients (61%) experienced brain fog. Concentration was affected by symptom severity (odds ratio [OR] 3.63, 95% confidence interval [CI] 1.26-10.46, p = 0.02). Short- or long-term memory loss was not affected. Moreover, symptom severity was related to brain fog (OR 3.16, 95% CI 1.05-9.51, p = 0.04). Patients with persistent symptoms had a concentration impairment associated with severity patterns (OR 24.3, 95% CI 1.73-340.11, p = 0.03). Conclusions: Brain fog is associated with symptom severity in COVID-19 survivors and lasts for more than eight months.
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The timely assessment of mental health is difficult since we lack the objective measurements of symptoms, especially for the Covid-19 pandemic quarantined students. Fortunately, smart phones can capture the real-world data such as the GPS traces and the phone active time et.al that link the behavioral patterns to the mental health. However, recent studies are based on a very small size of participants and only collect fewer phone features, which means that the effective predicting models which require various features are hardly adopted. In this paper, we develop an android application to record multidimensional data of users as well as a PHQ-9 and a SAS questionary, and we distribute it to 176 college students to collect larger scale data when in quarantine period. To address the unprecise problem of handcrafted feature extraction, we design an autoencoder machine learning model to monitor the student mental health. Extensive experiments indicate that the performance of the proposed method improves its F-1 score for PHQ-9 and SAS by 5% and 6% to the state of the current studies, respectively. © 2023 IEEE.
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The article describes the experimental measurements made at a low-voltage residential and educational power substation, in a point of common coupling. Two groups of experiments were carried out, in normal conditions and during the COVID-19 pandemic. Measurements were made using a power quality analyzer and include phase RMS voltages and line currents, total harmonic distortion and unbalance of phase voltages and line currents, neutral current, active, reactive and apparent powers, power factors and displacement power factors, Fresnel diagrams, and harmonic spectra. Measurements indicate significant differences of power quality indicators between the two measurement groups. © 2023 IEEE.
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PurposeThis study aims to identify the dietary patterns of two groups of subjects (with and without COVID-19), and to assess the relationship of findings with the prognosis of COVID-19 and metabolic risk parameters.Design/methodology/approachThis study included 100 individuals in the age range of 19–65 years. The medical history, and data on biochemical, hematological and inflammatory indicators were retrieved from the files. A questionnaire for the 24-h food record and the food intake frequency was administered in face-to-face interviews, and dietary patterns of subjects were assessed.FindingsIn individuals with COVID-19, the hip circumference, the waist-hip ratio and the body fat percentage were significantly higher (p < 0.05), and the muscle mass percentage was significantly lower (p < 0.05). Mediterranean diet adherence screener (MEDAS), dietary approaches to stop hypertension (DASH) and healthy eating ındex-2015 (HEI-2015) scores were low in the two groups. A linear correlation of DASH scores was found with the muscle mass percentage (p = 0.046) and a significant inverse correlation of with the body fat percentage (p = 0.006). HEI-2015 scores were significantly and negatively correlated with body weight, body mass index, waist circumference, hip circumference and neck circumference (p < 0.05). Every one-unit increase in MEDAS, DASH and HEI-2015 scores caused reductions in C-reactive protein levels at different magnitudes. Troponin-I was significantly and negatively correlated with fruit intake (p = 0.044), a component of a Mediterranean diet and with HEI-2015 total scores (p = 0.032).Research limitations/implicationsThe limitation of this study includes the small sample size and the lack of dietary interventions. Another limitation is the use of the food recall method for the assessment of dietary patterns. This way assessments were performed based on participants' memory and statements.Practical implicationsFollowing a healthy diet pattern can help reduce the metabolic risks of COVÍD-19 disease.Originality/valueDespite these limitations, this study is valuable because, to the best of the authors' knowledge, it is the first study demonstrating the association of dietary patterns with disease prognosis and metabolic risks concerning COVID-19. This study suggests that dietary patterns during the COVID-19 process may be associated with several metabolic risks and inflammatory biomarkers.
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Due to COVID-19 pandemic, body temperature measurement in commercial facilities is performed using a non-contact method. However, if the human body can be controlled in some way to disguise body temperature, a thermometer would have difficulty detecting an entrant with a fever. In this study, we propose a method to control body temperature measured at the wrist in order to demonstrate the vulnerability of temperature measurement at the wrist. Our device lowers body temperature by cooling the upper arm, thereby cooling blood flow and reducing the intensity of infrared radiation detected by a thermometer. The implemented device was used to cool the upper arm under three different conditions. The results showed that cooling the blood flow in the upper arm can lower the body temperature at the wrist. The cooled body temperature was difficult to maintain after the end of cooling, irrespective of the cooling intensity and cooling time. © 2022 ACM.
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Under the influence of COVID-19, it is recommended to ventilate to reduce the risk of infection in the room. In an air-conditioned room, window open can increased the ventilation rate that caused by indoor and outdoor temperature difference. However, there is a concern that opening window in the air-conditioned room will increase the heating and cooling load due to air leakage. In addition, it is difficult to maintain the appropriate ventilation rate because the outdoor air temperature changes time to time. To solve this problem, we have developed an automatic window opening system to control the natural ventilation rate. In this study, actual measurements were conducted to understand the operating performance of the system, and its effect on the indoor thermal environment. As a result, it was confirmed that the ventilation rate could be controlled by this system. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.
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To quantitatively evaluate the effect of increasing ventilation using the immediately practicable method on infection risk, the ventilation rate in a classroom was measured by the concentration decay method using CO2. The measured value was then substituted into the Wells-Riley model to evaluate aerosol infection risk in steady and non-steady states. In the classroom, the air change rate per hour (ACH) ranged from 3.1 to 10.2, and the local mean age of air tended to be larger near the outlet. It was also shown that opening the windows increased the ventilation rate the most, resulting in a more evenly distributed local mean age of air. We also showed that the aerosol infection risk in the classroom could be significantly reduced by increasing ventilation, suppressing vocalization, and wearing a mask, compared to some outbreaks of COVID-19. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.