Average Relative Humidity Research Articles

Orchard microclimate, tree water uptake and sweet cherry fruit quality under protected cropping.

Protected cropping systems (PCS) de-risk adverse climatic effects in intensive horticultural production but alter the growing environment. The objectives of this study were to investigate the effects of modern, commercial-scale PCS on sweet cherry orchard microclimate, tree water uptake and fruit quality. Sap flow sensors and weather stations were positioned at four locations under a 21 ha PCS at varying elevations (125, 114, 111, 102 m above sea level) and distances from the block boundary (105, 75, 60 or 50 m, referred to hereafter as Locations 1 to 4, respectively). Generalised additive models (GAMs) were used to predict the effect of individual climate parameters (temperature, relative humidity, solar radiation and wind speed) on tree sap flow at each of the four locations. Average and maximum temperatures and average minimum relative humidity (RH) were higher (15.9°C, 26.1°C and 49.0%) at locations with higher elevations and located further from the PCS boundary (locations 1 and 2) in contrast to locations at lower elevations and closer proximity to the PCS boundary (locations 3 and 4) (15.4°C, 24.6°C and 48.1%). Predicted sap flow was strongly correlated (r2 = 0.92) with time across the four locations under the PCS. GAMS modelling indicated that the hourly water uptake by trees within close proximity to the block boundary (locations 3 and 4) responded with greater intensity to increases in temperature and reductions in relative humidity, taking up on average 0.15 L h-1 (at temperatures >30°C) and 0.08 L h-1 (at RH<50%), respectively, in contrast to trees further under the PCS (locations 1 and 2) where average tree water uptake was 0.08 and 0.04 L h-1 at temperatures >30°C and RH<50%, respectively. Highest average predicted hourly tree sap flow was associated with high wind speeds (0.67 L h-1) and low relative humidity levels (0.61 L h-1). Fruit harvested from locations further from the PCS boundary had significantly higher dry matter content (18.2%), total soluble solids (17.8%) and compression firmness (311.3 g mm-1) in contrast to fruit closer to the PCS boundaries (16.1%, 15.7% and 258.3 g mm-1). This study provides greater understanding of the effects of PCS on microclimate and consequences for tree water uptake and fruit quality.

Have the prevalence of eczema symptoms increased in the Mexican pediatric population? Prevalence and associated factors according to Global Asthma Network Phase I

BackgroundIn children, atopic dermatitis or eczema is the most common inflammatory disease of the skin. According to the International Study of Asthma and Allergies in Childhood (ISAAC) Phase IIIB in Mexico, 5.8% of children and 4.9% of adolescents had eczema symptoms. In 2012, Global Asthma Network (GAN) was established to update the prevalence of eczema and estimate potential factors contributing to its development. ObjectiveTo estimate the prevalence and associated factors for atopic eczema symptoms and diagnosis in children and adolescents according to GAN Phase I and compare the results with ISAAC Phase IIIB in Mexico. MethodsA cross-sectional, multicenter survey was conducted in 15 Mexican centers during the period of 2015–2017 using the GAN Phase I questionnaires in children (6–7-year-olds) and adolescents (13–14-year-olds). The prevalences obtained from the GAN Phase I study, were compared with ISAAC Phase IIIB results; a Spearman's correlation analysis was conducted between temperature, relative humidity, and altitude and eczema symptoms, and a logistic regression was performed to predict current eczema symptoms by age group. ResultsA total of 35 777 children and 41 399 adolescents were included. Since ISAAC Phase IIIB, the prevalence of itchy rash in the past 12 months significantly increased in the children's group [6.6% (95% CI 5.7–7.4) vs 7.8 (95% CI 7.5–8.1), p = 0.000] and adolescents' group [5.8% (95% CI 5.0–6.7) vs 6.7% (95% CI 6.5–7.0), p = 0.000].In the adolescents' group, the prevalence of nocturnal awakenings caused by rash symptoms on more than one night per week had a negative correlation between altitude (Spearman's Rho = −0.558, p value = 0.031), and a positive correlation with the average annual temperature (Spearman's Rho = 0.604, p value = 0.017) and annual relative humidity (Spearman's Rho = 0.742, p value = 0.002). The most significant associations in children were the presence of sneezing or runny or blocked nose in the past 12 months [(OR 3.13, 95% CI 2.60–3.77), p = 0.000], the use of paracetamol in the first year of life ([OR 1.52, 95% CI 1.15–2.01), p = 0.003] and the use of antibiotics in the first year of life [(OR 1.30, 95% CI 1.08–1.55) p = 0.004]. Moreover, altitude at 100–1000 m above sea level was associated with current eczema symptoms in adolescents (p = 0.001). ConclusionsThere has been a significant increase in eczema symptoms in both age groups since ISAAC Phase IIIB study. Additionally, eczema symptoms were associated with temperature, relative humidity, asthma, hay fever symptoms, the use of paracetamol and antibiotics.

Acute Gaseous Air Pollution Exposure and Hospitalizations for Acute Ischemic Stroke: A Time-Series Analysis in Tianjin, China.

Background: Stroke has always been an important problem troubling human health. Short-term exposure to air pollutants is associated with increased hospital admissions. The rise of pollutants such as O3 has caused a huge social and economic burden. This study aims to explore the relationship between short-term exposure to ambient gaseous pollutants and daily hospitalizations for ischemic stroke, utilizing a four-year time-series study in Tianjin. Methods: Collecting the data of gaseous pollutants (NO2, SO2, CO, O3), meteorological data (including daily average temperature and relative humidity) and the number of hospitalizations due to ischemic stroke in Tianjin Medical University General Hospital from 2013 to 2016. Poisson regression generalized additive model with single-day and multi-day moving average lag structure was used to estimate adverse effects of gaseous pollutants on daily hospitalizations. Subgroup analysis was performed to detect modification effect by gender and age. Results: In total, there were 9081 ischemic stroke hospitalizations. After controlling for the meteorological factors in the same period, no significant findings were found with the increase of NO2, SO2, CO and O3 concentrations at most of the time in the single-pollutant model. Similarly, in the stratified analysis, no associations between gaseous pollutants and ischemic stroke were observed in this study. Conclusions: Short-term exposure to NO2, SO2, CO and O3 was not distinctly associated with daily hospitalizations for ischemic stroke in Tianjin. Multicenter studies in the future are warranted to explore the associations between gaseous pollution exposure and ischemic stroke.

The association between air pollutants, meteorological factors and tuberculosis cases in Beijing, China: A seven-year time series study

BackgroundTuberculosis (TB) is a severe public health problem globally. Previous studies have revealed insufficient and inconsistent associations between air pollutants, meteorological factors and TB cases. Yet few studies have examined the associations between air pollutants, meteorological factors and TB cases in Beijing. ObjectiveThe purpose of this study was to explore the impact of air pollutants and meteorological factors on TB in Beijing, and to provide novel insights into public health managers to formulate control strategies of TB. MethodsData on the daily case of TB in Beijing during 2014–2020 were obtained from Chinese tuberculosis information management system. Concurrent data on the daily PM10, PM2.5, SO2, NO2, CO and O3, were obtained from the online publication platform of the Chinese National Environmental Monitoring Center. Daily average temperature, average wind speed, relative humidity, sunshine duration and total precipitation were collected from the China Meteorological Science Data Sharing Service System. A distributed lag non-linear model was fitted to identify the non-linear exposure-response relationship and the lag effects between air pollutions, meteorological factors and TB cases in Beijing. ResultsIn the single-factor model, the excess risk (ER) of TB was significantly positively associated with every 10 μg/m3 increase in NO2 in lag 1 week (ER: 1.3%; 95% confidence interval [CI]: 0.4%, 2.3%) and every 0.1 m/s increase in average wind speed in lag 5 weeks (ER: 0.3%; 95% CI: 0.1%, 0.5%), and was negatively associated with every 10 μg/m3 increase in O3 in lag 1 week (ER: −1.2%; 95% CI: −1.8%, −0.5%), every 5 °C increase in average temperature (ER: −1.7%; 95% CI: −2.9%, −0.4%) and every 10% increase in average relative humidity (ER: −0.4%; 95% CI: −0.8%, −0.1%) in lag 10 weeks, respectively. In the multi-factor model, the lag effects between TB cases and air pollutants, meteorological factors were similar. The subgroup analysis suggests that the effects of NO2, O3, average wind speed and relative humidity on TB were greater in male or labor age subgroup, while the effect of CO was greater in the elderly. In addition, no significant associations were found between PM2.5, SO2, sunshine duration and TB cases. ConclusionOur findings provide a better understanding of air pollutants and meteorological factors driving tuberculosis occurrence in Beijing, which enhances the capacity of public health manager to target early warning and disease control policy-making.

Particulate matter may have a limited influence on maternal vitamin D levels

Evidence for an association between the amount of particulate matter (PM) in the atmosphere and vitamin D status of pregnant women is limited. We aimed to examine the independent association between PM and maternal levels of serum 25-hydroxyvitamin D (25OHD) during the second trimester and to explore possible modifications to the association by meteorological factors. 27,768 pregnant women presenting for prenatal examination who were tested for serum 25OHD concentration during the second trimester between January 1, 2016, and December 31, 2020, were included in this retrospective analysis. Exposure to PM was evaluated based on daily average PM with an aerodynamic diameter of ≤ 2.5 μm (PM2.5) and PM with an aerodynamic diameter of ≤ 10 μm (PM10). Corresponding meteorological data for daily average atmospheric temperature, atmospheric pressure, relative humidity, sunshine duration, and wind speed were collected. The maximum cumulative effects of PM2.5 occurred at lag 45 days, and the maximum cumulative effects of PM10 occurred at lag 60 days. In crude models, 45-day moving daily average PM2.5 concentrations were negatively associated with 25OHD levels (β, − 0.20; 95% CI − 0.21 to − 0.19), as were 60-day moving daily average PM10 concentrations (β, − 0.14; 95% CI − 0.15 to − 0.14). After adjusting for temporal and meteorological factors, the effect values were drastically reduced (adjusted β of PM2.5, − 0.032; 95% CI − 0.046 to − 0.018; adjusted β of PM10, − 0.039; 95% CI − 0.049 to − 0.028). Our study showed there was a small, independent, negative association between PM in the atmosphere and maternal serum 25OHD levels during the second trimester of pregnancy after adjusting for temporal and/or meteorological factors, which indicates that PM may have a limited influence on maternal serum 25OHD levels. Besides taking vitamin D supplements, pregnant women should keep participating in outdoor activities while taking PM protection measures to improve their vitamin D levels when PM levels are high in winter and spring.

Intraseasonal variation of the association between cold temperature and mortality risk in Shandong Province

Objective: To explore the intraseasonal variation in mortality risk from cold temperature exposure in Shandong Province. Methods: Mortality data in Shandong province from 2013 to 2018 were collected from the cause of death surveillance system of Shandong Center for Disease Control and Prevention. The basic information mainly included the date of death, age, gender, education level, cause of death, home address, etc. The daily meteorological data from China Meteorological Data Network mainly included the grid coordinate data of 0.01°×0.01° latitude and longitude, such as daily average temperature (℃) and daily average relative humidity (%). The cold season was from November to February. The first two months were the early cold season and the last two months were the late cold season. The extreme cold temperature was defined as the 10th percentile of the temperature range of cold season. Time-stratified case crossover design with distributed lag non-linear model analyzed the association between temperature and mortality and the association between extreme low temperature and mortality in different lag days in the cold season, and compared the intraseasonal differences between early (November-December) and late (January-February) cold season. Results: The temperature ranged from -17.3 ℃ to 18.6 ℃ in Shandong Province during the cold season from 2013 to 2018, and the P10 (extreme low temperature) was -13.7 ℃. The average daily temperature in the early cold season was (3.63±4.66) ℃. The temperature in the late cold season was (-0.09±3.70) ℃. The average daily relative humidity was (63.89±14.75) % in the early cold season and (62.27±14.19) % in the late cold season. This study included 1 473 300 deaths in the cold season in Shandong Province between 2013 and 2018. There were 824 601 (55.97%) males and 349 824 (23.75%) cases aged<65 years. There were 803 691 (54.55%) deaths due to circulatory diseases and 140 415 (9.53%) deaths due to respiratory diseases. The results of DLNM showed that the cumulative OR of extreme low temperature in the four months of cold season was 1.74 (95%CI: 1.63, 1.86) with the optimal temperature of 18.6 ℃ as the reference. The cumulative OR values of early and late cold season were 1.50 (95%CI: 1.32, 1.71) and 2.56 (95%CI: 2.12, 3.09), respectively (P<0.001). The lag effect lasted for 12 d. Conclusion: There is an intraseasonal variation of the association between cold temperature and mortality risk in Shandong Province. The mortality risk related to cold temperature in the late cold season is higher than that in the early cold season.

A time-series study on the association of ambient temperature with daily outpatient visits of eczema in Huizhou city

Objective: To explore the impact of environmental temperature exposure on eczema visits. Methods: Eczema clinic data from January 1, 2016 to December 31, 2019 were collected from the Huizhou Dermatology Hospital, and data on meteorological factors (average daily temperature and relative humidity) for the same period were derived from 86 meteorological stations of the Guangdong Provincial Climate Center. A distributed lag nonlinear model (DLNM) was used to assess the lagged effect of environmental temperature exposure on eczema, and a natural smooth spline function was used to control the nonlinear confounding of humidity. Results: There were 254 053 eczema outpatient visits at the Huizhou Dermatology Hospital within four years, with an average of 173.89 visits per day. The relationship between daily average temperature and the number of visits was non-linear (U shape). The risk of eczema increased by 2.20% (1.19%-3.21%) for every 1 ℃ decrease for the low temperature, and increased by 2.35% (1.24%-3.5%) for every 1 ℃ increase for the high temperature. The effect of high temperature was greater than that of low temperature. In all cases, 1.60% (0.44%-2.68%) of eczema outpatient visits were attributed to low temperature and the attributable number was 4 065 (1 128-6 798), while 6.33% (1.40%-10.87%) of eczema outpatient visits were due to high temperature and the attributable number was 16 082 (3 557-27 616). Conclusion: Both high temperature and low temperature are associated with increased risk of eczema.

The North-South difference of the relationship between cold spells and mortality risk of cardiovascular diseases in China

Objective: To analyze the North-South difference of the relationship between cold spells and mortality risk of cardiovascular diseases in China. Methods: The time series analysis method was used to collect the daily counts of cardiovascular mortality data, meteorological data and PM2.5 concentration in the cold season (November to March of the following year) from January 1, 2013 to December 31, 2018 in 280 districts and counties in China. The non-constrained distributed lag linear model was used to analyze the relationship between cold spells and mortality risk of cardiovascular diseases and its North-South difference in China. Results: From 2013 to 2018, the mean of daily average temperature of the cold season in 280 districts and counties was 5.4 ℃. The mean of daily average relative humidity was 64.4%, and the mean of daily average PM2.5 concentration was 73.7 μg/m3. The average cold spell days in each county was 11.7 days per year,the mean of daily average temperature on cold spell days was (-2.4±6.7) ℃, and M (Q1, Q3) was -1.5 (-5.1, 1.1) ℃. The average of daily number of cardiovascular disease deaths in each county/district was (6±5) cases, and M (Q1, Q3) was 5 (2, 8) cases. The percentage change (95%CI) in the South was 4.94% (3.69%, 6.20%) (lag 0 d), higher than that in the North [the percentage change (95%CI) was 1.49% (1.14%-1.84%) (lag 0-7 d)]. In the North, the mortality risk of ≥75 years old was relatively low among three age groups, with a percentage change (95%CI) about 1.63% (1.33%-1.93%) (lag 0-21 d). In the South, the mortality risk of ≥ 75 years old was relatively high among three age groups, with a percentage change (95%CI) about 5.18% (3.78%-6.59%) (lag 0 d). Conclusion: The mortality risk of cardiovascular diseases caused by cold spells in the South is higher than that in the North of China, and the risk peak occurs earlier in the South.

Dual‐Site Synergistic Passivation for Highly Efficient and Stable Perovskite Solar Cells

AbstractDefect passivation has been recognized as an effective strategy to improve efficiency and stability of perovskite solar cells (PSCs). In this work, in‐depth theoretical calculations and experimental characterizations reveal the dual‐site synergistic passivation of 1H‐benzimidazole (BIZ), and the conjugated structure of the benzene ring tends to increase the interaction between BIZ and perovskite. High‐quality perovskite films are thus achieved, with increased grain size, reduced defect density, and suppressed ion migration. Simultaneously, the reduced work function and optimized band alignment promote carrier transport, reducing nonradiative recombination, and loss of open‐circuit voltages, as well as fill factor. Consequently, the target PSC devices achieve a champion power conversion efficiency (PCE) of 24.59%, and 20.49% for perovskite solar module (a designated area of 27.5 cm2). The unencapsulated PSC maintains 91.49% of original PCE after storing in air with an average relative humidity of 40% for 2400 h. Moreover, the device exhibits remarkable the long‐term operational stability, maintaining 90.47% of initial PCE after continuously operating at the maximum power point for 1000 h. This study not only provides insights into the synergistic passivation of BIZ but also provides a strategy for the application of BIZ derivatives in the photovoltaic field.

Assessment of disease burden related to non-optimal temperature across China

Objective: To estimate the excess mortality attributed to non-optimal ambient temperature in China. Methods: Mortality data and meteorological data from 239 counties in 2013-2018 were collected to simulate the quantitative exposure-response relationship between the temperature and mortality using distributed lag nonlinear models for time series studies. Then the number of non-optimal-temperature-related excess deaths was assessed and the spatial distribution was explored. Results: There were averagely (12±8) cases of all-cause deaths per day per county from 2013 to 2018. The average daily temperature was (14.98±10.31)℃, and the daily average relative humidity was (68.79±17.25)%. The daily average O3 concentration was (58.95±34.96) μg/m³, and the daily average PM2.5 concentration was (54.97±45.56) μg/m³. The exposure-response curve between daily average temperature and all-cause mortality showed a "U" shape, and the theoretical minimum mortality temperature (MMT) corresponding to the minimum number of deaths was 21.60 ℃. When the temperature was higher than MMT, the heat-related health effect increased with the temperature rising. When the temperature was lower than MMT, the cold-related effect increased with the temperature decreasing. The attributable fraction (AF) of death caused by non-optimal temperature was 8.76% (95%CI: 8.07%-9.10%), and the AF of death caused by cold effect and heat effect was 7.21% (95%CI: 6.51%-7.57%) and 1.55% (95%CI: 1.46%-1.61%), respectively. The excess deaths from non-optimal temperature in 2015 were 519 122, 72.98% of which could be attributed to low temperature. The number of excess deaths caused by non-optimal temperature mainly showed a decreasing trend from the east to the west, relatively high (117 522) in East China. Heilongjiang Province (in Northeast China) had the most excess deaths (26 924) caused by low temperature, and Guangdong Province(in South China) had the most excess deaths (27 763) caused by high temperature. Conclusion: The non-optimal temperature has a significant impact on health and causes a considerable burden of disease in China with obvious spatial heterogeneity.

A coupled hygro-thermo-mechanical fiber beam model for reinforced concrete structures

The mechanical behavior of reinforced concrete is affected by the environmental fluctuations of temperature and humidity. In traditional structural analysis of the using beam element, the influence of coupled hygro-thermo-mechanical effect was considered by correction coefficient terms based on data fitting of specimens, which was not very suitable for the analysis of large or complex structures. In order to catch complex behavior of reinforced concrete using beam element, a coupled hygro-thermo-mechanical fiber beam model is developed for the analysis. The model uses a sequential coupled analysis approach based on the framework of original microprestress solidification (MPS) theory and fiber beam element method, which contains important features of reinforced concrete beam such as non-uniform ageing, creep, shrinkage, thermal dilation. Several concrete beam and reinforcement concrete beam experiment data, contrasting examples between the fiber beam element model and conventional 3D solid element model and a typical example of reinforced concrete box beam on structural scale were used to verify the presented model. Overall, good results were obtained in all the tests. The results show that the MPS intrinsic creep property could predict the behavior of concrete beams well. Area weighted average temperature and average relative humidity is an efficient simplified method to catch the MPS intrinsic creep property. Fiber beam element model coupled with MPS intrinsic creep property and a finer subdivision scheme can predict the behavior of beam well under complicated conditions as well as 3D solid element model. The model developed in this study can be used for large structures efficiently.

Efficacy of Botanicals Against Mustard Aphid (Lipaphis Erysimi Kalt.) (Homoptera: Aphididae) On Brassica Campestris L.

Efficacy of neem leaf extract, mahogany seed dust, and neem seed kernel dust against the mustard aphid Lipaphis erysimi Kalt., (Homoptera: Aphididae) on the mustard plant (Brassica campestris L.) was investigated during November 2014 to January 2015. The trial included four treatments, namely T1: neem leaf extract, T2: mahogany seed dust, T3: neem seed kernel dust, T4: control. The treatments began 22 DAS and were repeated every 7 days. T4 had the maximum number (9500 ± 1226.3) of aphid pest population at 57 DAS, and the lowest number (3 ± 0.9) of aphid pest population was found in T4 at 29 DAS. The aphid population was found to be nil at 22 and 71 DAS in all treatments. Furthermore, in case of T2, the aphid population was zero at 29 DAS. There was no significant difference in aphid counts between the treatments, according to the ANOVA test. Only in T2, the aphid counts showed a significant difference by replicates. But the number of fruits and seed output of mustard were affected by the efficacy of botanicals against mustard aphid. T1 exhibited the highest percentage of fruits (27.7%), seeds (42.64%), and seed weight (54.9%). T1 had the highest proportion of healthy seed (75.91%), whereas T4 had the highest percentage of defective seed (45.49%). Aphid population is negatively correlated to average temperature and relative humidity in all treatments. Bangladesh J. Bot. 51(3): 615-623, 2022 (September)

COVID-19 transmission in Africa: estimating the role of meteorological factors

Climate variables play a critical role in COVID-19’s spread. Therefore, this research aims to analyze the effect of average temperature and relative humidity on the propagation of COVID-19 in Africa's first four affected countries (South Africa, Morocco, Tunisia, and Ethiopia). As a result, policymakers should develop effective COVID-19 spread control strategies. For each country, using daily data of confirmed cases and weather variables from May 1, 2020, to April 30, 2021, generalized linear models (Poisson regression) and general linear models were estimated. According to the findings, the rising average temperature causes COVID-19 daily new cases to increase in South Africa and Ethiopia while decreasing in Morocco and Tunisia. However, in Tunisia, the relative humidity and daily new cases of COVID-19 are positively correlated, while in the other three countries, they are negatively associated.

On the applicability of some existing tropospheric scintillation prediction models for Ikeja and Abuja, Nigeria

Tropospheric scintillation which causes rapid fluctuation of signal due to the turbulence in the atmosphere is of significance in satellite link budget design. Existing models that predict the intensity of scintillation such as Karasawa, International Telecommunication Union Radiocommunication (ITU-R) Sector, Otung, Van de Kamp and Ortgies are not appropriate for predicting scintillation intensity (SI) in Nigeria due to localization of the models to particular regions. The monthly average air temperature and relative humidity for Ikeja and Abuja, Nigeria, retrieved from the Nigerian Meteorological Centre data bank were used for the investigation. An elevation angle of 5° was used as look angle, antenna diameter of 0.3 m, 40 GHz and 45 GHz frequencies were considered in this study. The existing scintillation model values were then compared with the measured values for the two locations to determine the best performance model. The SI results at 40 GHz and 45 GHz were obtained for each of the existing models. It could be deduced from the results obtained that orgies model values were the most closet to the measured values. Therefore, Orgies-N model was the most appropriate for SI prediction in Ikeja and Abuja.

Analysis of the Influence of Meteorological Factors on Air Pollutants in Nanning from 2018 to 2020

Through the analysis of meteorological factors in Nanning from 2018 to 2020, including temperature, humidity, wind speed, sunshine, air pressure and other indicators, this study summarizes the change characteristics of meteorological factors. The descriptive statistics of the air quality in Nanning in the past three years show that PM10 and O3 are the main reasons affecting the air quality in Nanning. By means of correlation analysis and stepwise regression, the correlation degree between meteorological factors and PM10 and O3 was explored, and the relationship between independent variables and dependent variables was established. The conclusions are as follows: (1) There is a significant correlation between PM10,O3 concentrations and meteorological factors. (2) Average relative humidity, average wind speed and average air temperature can explain 42% PM 10, and average relative humidity, average wind speed, average air temperature and sunshine hours can explain 66.3% O3.

Monitoring of Atmospheric Corrosion in a Mass Rapid Transit (MRT) Tunnel

A study has been conducted to measure uniform corrosion due to the tunnel environment in the mass rapid transit North East Line (NEL) in Singapore. The study was aimed at investigating the corrosivity of the atmospheric environment in the NEL to enhance understanding on the maintenance of metallic components in a tunnel. The corrosivity levels at the buffer areas of ten stations along the NEL were monitored over a period of two years. The measurements were based on physical metal coupons as well as real-time monitoring systems using electrical resistance sensors. The corrosivity levels measured at different exposure sites showed differences, but were generally low and could be generally categorised as G1 according to ISA standard 71.04:2013. The reason for the low corrosivity levels was likely to be due to the relatively mild temperature and low (<60%) average relative humidity.

Drought and ozone air quality in California: Identifying susceptible regions in the preparedness of future drought

California experienced extreme and prolonged drought conditions during the early 2010s. To date, little is known regarding the influence of drought on air quality. Our study quantified site-specific associations between drought (defined by the Standardized Precipitation-Evapotranspiration Index; SPEI) and daily maximum 8-h ozone (O3) concentrations for California, USA, and then pooled these associations for the years 2009–2015. Overall, ambient O3 concentration was higher during droughts by 1.18 ppb (95% confidence interval (CI) = 1.00–1.36). The sensitivity of O3 to drought was greater during the warm season than during the cool season (1.73 ppb versus 0.79 ppb higher O3 during droughts) with substantial regional variation. In a pooled analysis with meteorological parameters as potential effect modifiers, the spatial heterogeneity of drought-O3 associations was explained strongly by average relative humidity for each season (71.9% (warm season) and 73.4% (cool season) of the drought-O3 associations explained), followed by the drought-related changes in relative humidity (47.6% (warm season)) and temperature (53.6% (cool season)). The pooled regression further identified regions susceptible for drought-related O3 increases as those with relatively low average relative humidity (10–25th percentiles or 44.3–47.3%) and larger drought-related decrease in relative humidity and increase in temperature. As the drought events are projected to occur with increased frequency and intensity in the era of climate change, the excess health burdens from O3 exposures attributed to the projected drought events need to be taken into account when allocating air quality and health resources. The impacts of O3 on health during droughts would confound the health burdens from the drought itself.

Influence of environmental variables on functional capacity in patients with lung disease

Air pollution is related to negative impacts mainly on people with Chronic Respiratory Diseases (CRD), reflecting on respiratory health, reduced physical performance and so on. The objective was to investigate the influence of meteorological and air quality variables on the functional capacity of patients with CRD. This was a descriptive, retrospective and cross-sectional study of information collection in a database from 2016 to 2019. For the analysis of environmental variables, three different databases were used, one from the automatic air quality monitoring station in Novo Hamburgo, and the weather stations of Novo Hamburgo and Campo Bom (RS). The monitored data were: NO2, CO, O3, PM10, PM2,5, average temperature, minimum temperature, maximum temperature, precipitation, average wind speed and relative humidity. The sample consisted of 85 individuals from the Pulmonary Rehabilitation Program (PRP), where the variables spirometry and six-minute walk test (6MWT) were collected. It was observed that the higher the concentration of PM10 and the higher the minimum temperature, the lower the spirometric results. Furthermore, the greater the concentration of PM2.5, the shorter the distance that the individual travels. A relationship was found between environmental data and functional tests, where individuals with CRD are more sensitive to high levels of air pollutants, as well as to lower temperatures.

Experimental study on the heating and humidifying performance of fan coil units with humidification modules in severe cold regions

In order to solve the problem of low relative humidity in buildings and dispersion of existing heating and humidification equipment during the heating season in severe cold regions, a fan coil unit prototype with a humidification module was developed, and the heat is provided by an air source heat pump. The humidification module was made of parallel porous plates, which were infiltrated by the water using principle of capillary siphon. To explore the performance of the unit, an experimental bench was established in Harbin, China. The results show that the developed prototype can provide above 40 % RH while maintaining the room temperature. The heat absorbed by the water evaporation of the rated humidification capacity only accounts for 3.6 % of the nominal heating capacity of the fan coil unit. When unorganized fresh air infiltrated into the building, compared with the case of no humidification, the humidification reduced the temperature only 0.3 °C, the average relative humidity was increased by 33.8 %, the average humidity ratio was increased by 5.7 g/kg in the indoor stable phase, and the predicted percent dissatisfied in the standing occupant decreases to 9.55. Even if 30 m3/h of fresh air with low temperature and humidity was introduced into the building, the unit can ensure that the indoor temperature was above 20 °C and the relative humidity can be maintained at 30 %. In addition, in the rising stage of temperature and humidity, the humidification capacity of the unit is above 200 g/h.

Predicting the effect of climatic factors on diversity of flavor compounds in Daqu fermentation

Traditional fermented foods are usually produced by spontaneous fermentation, which is dependent on climatic conditions. It is important to unveil the effect of climatic conditions on spontaneous food fermentation. Here, this study aimed to unveil the regulation of climatic factors on microbiota structure and production of flavor compounds in spontaneous fermentation of Daqu (the starter for Chinese liquor fermentation). The diversity indexes of both microbiota and flavor compounds were significantly different (P < 0.01) across four seasons. Mantel test showed that climatic factors, including daily average temperature (R2 = 0.41, P = 0.019) and relative humidity (R2 = 0.38, P = 0.036), played important roles in the variation of microbiota and flavor compounds. A model was constructed to predict the diversity of flavor compounds, the parameter determining the quality of Daqu, based on these two climatic factors. The maximal value of diversity of flavor compounds reached 3.67, when daily average temperature was 18.89 °C and relative humidity was 49.21%. It increased by 70.69% compared to the lowest value 2.15. This study shed new light on the effect of climatic factors on the flavor compound production in spontaneous food fermentation. It would help improve and stabilize quality of spontaneously fermented foods.