Nitrogen Dioxide Research Articles

Organic‐Based Chemiresistive Sensors for Detection of Water‐Soluble Gases: Strategies and Roadmap for Enhancing Sensing Performance

AbstractTraditional organic‐based chemiresistive sensors have been a key area of research due to their portability, low power consumption, low cost, turnability, and possibility for miniaturization. However, their real‐world applications have remained restricted by their low selectivity, low sensitivity, and low stability under demanding conditions, such as extreme temperature, humidity, and pH. As such, this review aims to lay the foundation for enhancing the performance of these gas sensors via chemical and physical modifications. To this end, an insight into the building blocks of chemiresistive gas sensors and the attributes of the main four gases (ammonia, carbon dioxide, hydrogen sulfide, and nitrogen dioxide) under aqueous conditions are provided. Such features ultimately determine the enhancement strategy that is best suited to improve the chemiresistive gas sensors performance. Furthermore, this article provides an outlook into the current bottleneck in sensor development and its translation from lab to end‐consumer use. Overall, this review aims to serve as a roadmap for developing next‐generation, high performing chemiresistive gas sensors.

Measured air quality impacts after teaching parents about cooking ventilation with a video: a pilot study

Abstract Background Cooking-related emissions contribute to air pollutants in the home and may influence children’s health outcomes. Objective In this pilot study, we investigate the effects of a cooking ventilation intervention in homes with gas stoves, including a video-based educational intervention and range hood replacement (when needed) in children’s homes. Methods This was a pilot (n = 14), before-after trial (clinicaltrials.gov #NCT04464720) in homes in the San Francisco Bay Area that had a school-aged child, a gas stove, and either a venting range hood or over-the-range microwave/hood. Cooking events, ventilation use, and indoor air pollution were measured in homes for 2–4 weeks, and children completed respiratory assessments. Midway, families received this intervention: (1) education about the hazards of cooking-related pollutants and benefits of both switching to back burners and using the range hood whenever cooking and (2) ensuring the range hood met airflow and sound performance standards. The educational intervention was delivered via a video developed in conjunction with local youth. Results We found substantially increased use of back burners and slight increases in range hood use during cooking after intervening. Even though there was no change in cooking frequency or duration, these behavior changes resulted in decreases in nitrogen dioxide (NO2), including significant decreases in the total integrated concentration of NO2 over all cooking events from 1230 ppb*min (IQR 336, 7861) to 756 (IQR 84.0, 4210; p < 0.05) and NO2 collected on samplers over the entire pre- and post-intervention intervals from 10.4 ppb (IQR 3.5, 47.5) to 9.4 (IQR 3.0, 36.1; p < 0.005). There were smaller changes in PM2.5, and no changes were seen in respiratory outcomes. Impact This pilot before-after trial evaluated the use of a four-minute educational video to improve cooking ventilation in homes with gas stoves and one or more school-aged children. Participant behavior changed after watching the video, and there were decreases in indoor air pollutant concentrations in the home, some of which were significant. This brief video is now publicly available in English and Spanish (wspehsu.ucsf.edu/projects/indoor-air-quality), and this provides suggestive evidence of the utility of this simple intervention, which could be particularly beneficial for households that have children with asthma.

Temporal characterization of NOx and its relationship with O3 at a riverine site of Foshan

Nitrogen dioxide (NO2) is a crucial precursor of tropospheric O3. This study undertakes continuous measurements of nitric oxide (NO), nitrogen dioxide (NO2) and ozone (O3) at Shishan Port (SSP), a riverine site in Foshan, China. Oxides of nitrogen (NOx = NO + NO2) exhibit a distinct seasonality, with high concentrations in winter and low concentrations in summer. The daily average concentration of NOx is 30.5 ppb, with high concentrations in the evening and morning and low concentrations in the afternoon. The variation of the total oxidant (Ox = O3 + NO2) with the levels of NOx was examined to infer the atmospheric sources of Ox as the sum of a local contribution dependent on NOx and a regional contribution independent of NOx. The local contribution predominates during low wind speed and calm weather in winter. The case analysis of a typical NO2 pollution episode affirms that the increase of NO2 at night in SSP is significantly influenced by the exhaust emissions of passing ships, atmospheric diffusion conditions and the O3 concentration generated during the day. Due to the chemical coupling of NOx and O3, along with regional transport, the levels of NOx and O3 are inextricably linked yet complicated.

Large offshore wind farms have minimal direct impacts on air quality

Abstract Wind power has rapidly grown over the past decade because it is clean, renewable, and abundant. However, wind farms can affect local weather and possibly alter the transport, diffusion, and concentration of air pollutants. Given the unprecedented expansion of offshore wind farms planned along the U.S. East Coast by the Bureau of Ocean Energy Management (BOEM), this study aims to investigate if and how those future offshore wind farms might directly affect air pollution along the densely populated East Coast, in particular, the concentrations of ozone (O3), fine particulate matter (PM2.5), sulfur dioxide (SO2), and nitrogen dioxide (NO2). These pollutants are regulated at the federal and state levels and are harmful to human health. We exclusively study the direct effects of the wind turbines on air pollution (via meteorological changes), rather than investigating the indirect impacts of replacing fossil-fuel power plants with wind farms. We first run a numerical meteorological model, the Weather Research and Forecast (WRF) model, to simulate the meteorology along the U.S. East Coast during the summer of 2018 in two scenarios, with and without the wind farms. Then we use the output of these two sets of simulations from the WRF model as input to the Comprehensive Air Quality Model with extensions (CAMx) to simulate the changes in air quality in the study domain due to the wind farms. On average, we find a minor increase in O3 levels within the wake of the New Jersey WEA. The minor changes to O3 can be attributed to the slight temperature increase below the turbine hub height, within the rotor area, as well as a significant decrease in wind velocity in the wake of the turbines and a slight increase in VOCs. In addition, we report that the other three pollutants remain unchanged in the presence of wind farms. In summary, the direct impacts on air pollution by the BOEM-planned offshore wind farms are expected to be negligible.

Observational study of ground-level ozone and climatic factors in Craiova, Romania, based on one-year high-resolution data.

Air pollution is a multifaceted issue affecting people's health, environment, and biodiversity. Gaining comprehension of the interactions between natural and anthropocentric pollutant concentrations and local climate is challenging. This study aims to address the following two questions: (1) What is the influential mechanism of climatic and anthropogenic factors on the ground-level ozone (O3) concentrations in an urban environment during different seasons? (2) Can the ozone weekend effect be observed in a medium-sized city like Craiova, and under which conditions? In order to answer these questions, ozone interactions with meteorological parameters (temperature, pressure, relative humidity) and pollutant concentrations (particulate matter, carbon dioxide, volatile organic compounds, formaldehyde, nitrogen dioxide, nitric oxide and carbon monoxide) is evaluated based on a one-year dataset given by a low-cost sensor and one-year dataset provided by the National Environment Agency. Using two statistical analysis programs, Python and SPSS, a good understanding of the correlations between these variables and ozone concentration is obtained. The SPSS analysis underscores the significant impact of three meteorological factors and nine other pollutants on the ozone level. A positive correlation is noticed in the summer when sunlight is intense and photochemical reactions are elevated. The relationship between temperature and ozone concentration is strong and positive, as confirmed by Spearman's rho correlation coefficient (r = 0.880). A significant negative correlation is found between relative humidity and ozone (r = -0.590). Moreover, the analysis shows that particulate matter concentrations exhibit a significant negative correlation with ozone (r ≈ -0.542), indicating that higher particulate matter concentrations reduce ozone levels. Volatile organic compounds show a significant negative correlation with ozone (r = -0.156). A negative relationship between ozone and carbon dioxide (r = -0.343), indicates that elevated carbon dioxide levels might also suppress ozone concentrations. A significant positive correlation between nitrogen dioxide and ozone (r = 0.060), highlights the role of nitrogen dioxide in the production of ozone through photochemical reactions. However, nitric oxide shows a negative correlation with ozone (r = -0.055) due to its role in ozone formation. Carbon monoxide has no statistically significant effect on ozone concentration. To observe the differences between weekdays and weekends, T-Test was used. Even though significant differences were observed in temperature, humidity, carbon dioxide, volatile organic compounds, nitrogen dioxide, nitric oxide and carbon monoxide levels between weekdays and weekends, the T-Test did not highlight a significant weekend ozone effect in a mid-sized city as Craiova. Using Python, the daily values were calculated and compared with the limit values recommended by the World Health Organization (WHO) and European Environment Agency (EEA). The WHO O3 recommended levels were exceeded for 13 times in one year. This study offers a comprehensive understanding of ozone pollution in a mid-sized city as Craiova, serving as a valuable reference for local decision-makers. It provides critical insights into the seasonal dynamics of ozone levels, emphasizing the significant role of temperature in ozone formation and the complex interactions between various pollutants and meteorological factors.

Tropospheric ozone precursors: global and regional distributions, trends, and variability

Abstract. Tropospheric ozone results from in situ chemical formation and stratosphere–troposphere exchange (STE), with the latter being more important in the middle and upper troposphere than in the lower troposphere. Ozone photochemical formation is nonlinear and results from the oxidation of methane and non-methane hydrocarbons (NMHCs) in the presence of nitrogen oxide (NOx=NO+NO2). Previous studies showed that O3 short- and long-term trends are nonlinearly controlled by near-surface anthropogenic emissions of carbon monoxide (CO), volatile organic compounds (VOCs), and nitrogen oxides, which may also be impacted by the long-range transport (LRT) of O3 and its precursors. In addition, several studies have demonstrated the important role of STE in enhancing ozone levels, especially in the midlatitudes. In this article, we investigate tropospheric ozone spatial variability and trends from 2005 to 2019 and relate those to ozone precursors on global and regional scales. We also investigate the spatiotemporal characteristics of the ozone formation regime in relation to ozone chemical sources and sinks. Our analysis is based on remote sensing products of the tropospheric column of ozone (TrC-O3) and its precursors, nitrogen dioxide (TrC-NO2), formaldehyde (TrC-HCHO), and total column CO (TC-CO), as well as ozonesonde data and model simulations. Our results indicate a complex relationship between tropospheric ozone column levels, surface ozone levels, and ozone precursors. While the increasing trends of near-surface ozone concentrations can largely be explained by variations in VOC and NOx concentration under different regimes, TrC-O3 may also be affected by other variables such as tropopause height and STE as well as LRT. Decreasing or increasing trends in TrC-NO2 have varying effects on TrC-O3, which is related to the different local chemistry in each region. We also shed light on the contribution of NOx lightning and soil NO and nitrous acid (HONO) emissions to trends of tropospheric ozone on regional and global scales.

High-sensitivity NO2 fluorescence sensor based on a QDs@Aerogels/SM composite nanofilm

Quantum dots (QDs) exhibit excellent optical and chemical properties, making them advantageous for fluorescence sensing. However, gas sensor using QDs is often hampered by challenges such as gas diffusion and low concentration. This work describes the development of a nitrogen dioxide (NO2) fluorescence gas sensor that utilizes a QDs@Aerogels/SM composite nanofilm containing CdTe QDs modified by reduced glutathione (GSH), silica microspheres (SMs), and silica aerogel. The SM and porous aerogels create a uniform porous structure that enhances the distribution of QDs. Compared to the pure QDs film, the QDs@Aerogels/SM composite film exhibits enhanced fluorescence intensity. The porous structure promotes the adsorption of NO2, which improves the detection sensitivity. The QDs@Aerogels/SM composite film was applied in a portable gas sensor. The sensor demonstrates a good linear response to NO2 gas in the range of 0–10 ppm, with an ultra-low detection limit of 0.096 ppm and high selectivity. The uniform distribution of aerogel and SM enhances the stability of the composite nanofilm, and the fluorescence of the films remains virtually unchanged over a period of 60 days which ensures its optimal performance over extended periods of use. The fluorescent NO2 sensor demonstrated selective and sensitive quenching upon exposure to NO2, making it ideal for environmental monitoring and further applications.

Air Quality Legislation in Australia and Canada—A Review

Air pollution is a pervasive global issue affecting human health, ecosystems, and the environment. This paper reviews the evolution and implementation of air quality legislation in Australia and Canada, providing a comparative analysis of their approaches to managing air pollution. Both countries have established robust legal frameworks to address air quality issues, involving governmental policies, regulatory mechanisms, and collaborative efforts among stakeholders. Australia began its air quality regulation at the state level in the 1950s, evolving into a national framework with the National Environment Protection Measure for Ambient Air Quality in 1998. In contrast, Canada centralized its efforts with the Clean Air Act in 1971, complemented by the National Air Pollution Surveillance program. Key findings reveal that, while both nations have achieved significant improvements in air quality, challenges remain in addressing the broader impacts of air pollution, such as climate change and health-related economic burdens. Australia’s air quality standards are generally more stringent than Canada’s for particulate matter but more relaxed for sulfur dioxide, nitrogen dioxide, and ozone. Both countries employ advanced air quality monitoring and reporting systems, with Australia’s Air Quality Index and Canada’s Air Quality Health Index providing critical public health information. The study highlights the need for continuous improvement and a more integrated approach to air quality management. By examining the legislative and regulatory landscapes of Australia and Canada, this paper offers valuable insights for other countries striving to enhance their air quality governance and mitigate the adverse effects of air pollution on a global scale.

In Situ Generated 1‐Naphthylmethyl Radicals From Bis(1‐Naphthylmethyl)tin Dichlorides: Utilization For C‐C, C‐N, and C‐O Bond‐Forming Reactions

The in situ‐generated 1‐naphthylmethyl radicals from the thermolysis of bis(1‐naphthylmethyl)tin dichlorides combine with persistent organic radicals, 4‐hydroxy‐TEMPO or 4‐oxo‐TEMPO designs C−O bond forming products. Subsequently, the C‐N bond occurs when the 1‐naphthylmethyl radicals unite with nitric oxide (NO) under a nitrogen atmosphere.In contrast, the oxidation instead of the addition reaction predominantly happens in the 1‐naphthylmethyl radicals when nitrogen dioxide contains a high oxidation state nitrogen center, i.e., N(IV) used.The by‐product, dodecanuclear organotin cages, with twelve peripheral naphthyl units, could be isolated from the 4‐hydroxy‐TEMPO reaction. Besides, the synthesis of unsymmetrical diarylmethanes RArCH2 (R = 1‐naphthyl, 2,4,6‐Me3C6H2, 3‐ and 4‐MeC6H4, phenyl, 4‐ClC6H4; Ar = 4‐MeOC6H4, 3,4‐, 2,4‐ and 2,5‐Me2C6H3) in high yields and with good regioselectivity is reported. This new methodology involves the iodine‐mediated thermolysis of bis(arylmethyl)tin dichlorides (RCH2)2SnCl2 and an excess of an arene. This reaction involves homolytic cleavage of Sn–C bonds to give arylmethyl radicals that react with iodine in the presence of SnCl2 to give the corresponding cations, which undergo electrophilic attack on the arene. Functionalised diarylmethanes have wide applications in pharmaceutical, agrochemical, and materials sciences. Alternative synthetic approaches to this class of organic compounds that avoid using a transition‐metal catalyst or a strong Lewis acid are desirable.

Evaluating the Spatio-Temporal Distribution of Nitrogen Dioxide, Land Surface Temperature and NDVI in Nairobi City County

Abstract. Cities are becoming larger and it is estimated that by the year 2050, more than 6 billion people will be living in cities. As cities expand and grow, the quality of life and conditions will also transform. An integral part of environmental studies has been statistical analysis in modelling the spatial dynamics of land use changes. The research involved the use of satellite imagery to determine yearly averaged values of LST and NDVI from Landsat 8 OLI/TIR and monthly mean values of Nitrogen Dioxide (NO2) from Sentinel 5-Precursor (Sentinel-5P) across Nairobi City County. The datasets covered the period 2019, 2020, 2021, 2022 and 2023 and were analysed in Google Earth Engine. Results indicated that the yearly mean values in NO2 and LST in 2020 reduced by 2% and 12% respectively from 2019, while the mean NDVI value significantly increased by 28% in 2020 from 2019. NO2 has a negative correlation with LST in all years and a positive correlation with NDVI. Pearson correlation with population densities in constituencies in Nairobi in 2019 and 2023 indicate a negative correlation with NDVI and a positive correlation with NO2 and LST. Constituencies that have higher population densities tend to have lower vegetation densities and higher NO2 concentrations and temperature. Vegetation therefore plays a crucial role in air quality and that climatic factors such as precipitation and temperature influence the concentration of pollutants.

Emission control in a dual fuel low temperature combustion engine at intermediate loads

Intermediate to high load operation in dual fuel reactivity controlled compression ignition (RCCI) techniques is restricted due to uncontrolled combustion that causes engine knocking. Dual fuel strategies with advanced pilot injection and near-top dead center (TDC) main injection timings are reported to enhance combustion control, albeit with increased soot emissions, reduction of thermal efficiency, and emergence of an intricate trade-off between total hydrocarbon (THC) and oxides of nitrogen (NOx) emissions. In order to address these conflicting issues, an intermediate engine load, corresponding to 6 bar gross indicated mean effective pressure at 1500 and 2200 rev/min engine speeds was investigated in this work. The main objectives of this work are (1) to obtain combination of control parameters to achieve near-zero engine-out NOx and soot emissions and high thermal efficiency while minimizing THC and CO emissions; (2) to understand the effectiveness of diesel oxidation catalysts (DOCs) for the oxidation and reduction of exhaust gas species in the dual fuel mode; and (3) to understand the oxidation characteristics of the soot generated from the dual fuel mode. Optimum dual fuel low temperature combustion strategies, in terms of diesel injection timings, quantity and exhaust gas recirculation levels, were identified using the statistical multi response signal to noise (MRSN) ratio method in which NOx, soot and indicated efficiency were response variables. The performance of commercial DOCs, with different precious metal (Pt and/or Pd) loadings, were also studied at optimum dual fuel strategies for gasoline-diesel dual fuel operations. High DOC outlet temperatures (>∼340°C), due to the exotherm generated by the oxidation of high concentrations of THC and carbon monoxide (CO) emissions from dual fuel operations, resulted in greater than 90% THC conversion efficiency. The exotherm decreased the nitric oxide (NO) oxidation whereas the nitrogen dioxide (NO2) reduction reactions were favored over the DOC in the dual fuel mode at the intermediate load operating condition. Thermogravimetric analysis of the soot showed higher activation energy (177.2 kJ/mol), formed at the dual fuel optimum condition, relative to the activation energy (162.7 kJ/mol) of the soot formed in conventional diesel combustion (CDC).

Underappreciated roles of soil nitrogen oxide emissions on global acute health burden

The recognized importance of ambient fine particulate matter (PM2.5), ozone (O3), and nitrogen dioxide (NO2) on human health has prompted the world to enact increasingly strict regulations on anthropogenic nitrogen oxides (NOx) emissions. However, the health concerns from soil NOx, potentially driven by fertilizer input but conventionally categorized as natural sources, remain less studied. Here, we emphasize the underappreciated roles of soil NOx emissions on health burden attributable to short-term PM2.5, O3, and NO2 exposure. Globally, we quantify acute health effects using machine-learning-based daily exposure estimates and identify influences of soil NOx emissions based on chemical transport model simulations. We find that 72.3% of the globe is affected by soil NOx emissions, whose contributions to short-term PM2.5, O3, and NO2 pollution lead to 13.9 (95% Confidence Interval [CI]: 9.1-18.8), 26.0 (18.2-34.2), and 13.9 (10.3-17.5) thousand premature mortality, respectively, in 2019. With distinct variations in regions, seasons, and pollutants, soil NOx-originated air pollution poses a global health concern, particularly for developing regions and intensively agricultural areas. In response to the intensive fertilizer use, South Asia, Southern Sub-Saharan Africa, and Central Europe witness the largest soil NOx-related health burden of up to 1.6 (95% CI: 1.1-2.1) mortality per 100k population. The overall health risk peaks in May, with O3 pollution typically dominating the soil NOx-attributable health burden during warm seasons and NO2 or PM2.5 during cold months. Our study highlights the necessity of dynamically adapted agricultural strategies for health-oriented multi-pollutant control, among which the improved use of synthetic fertilizers deserves priority under the ever-changing climate.

Study on the electrochemical oxidation mechanism of sulfamethoxazole using three-dimensional boron-doped diamond

In this study, we prepared a novel three-dimensional boron-doped diamond (BDD) electrode. Subsequently, we systematically conducted an electrochemical oxidation reaction on sulfamethoxazole (SMX) using a BDD anode and a platinum plate (Pt) cathode. The effects of initial concentration, current density, initial pH, and carrier electrolyte on SMX degradation were investigated. The SMX was completely removed after 4 h of electrolysis at a current density of 30 mA/cm2, 0.1 mol sodium sulphate as the supporting electrolyte, and a pH of 7. Additionally, the COD removal rate was 65.6 %, while the energy consumption was 40.1 %. Compared with two-dimensional BDD electrode degradation, the energy saving was 54 %. Density functional theory (DFT) and high-performance liquid chromatography (HPLC) were used to analyse the SMX degradation mechanism. Three possible degradation pathways were proposed: ·OH substitution of the amino group in the aromatic ring, oxidation of the amino group to nitrogen dioxide, and addition of ·OH to the isoxazole ring. The active sites detected in the reaction corresponded closely with the calculated results using DFT. Moreover, ECOSAR toxicity analysis was applied to evaluate the toxicity of the intermediates produced during electrolysis. We discovered that the toxicity of SMX and its intermediates decreased significantly during electrolysis.

Estimating monthly NO2, O3, and SO2 concentrations via an ensemble three-stage procedure with downscaled satellite remote sensing data and ground measurements

The gaseous air pollutants nitrogen dioxide (NO2), ozone (O3), and sulfur dioxide (SO2), in addition to particulate matter (PM2.5), are known to be associated with many adverse health effects. However, exposure estimates may not be available in rural or mountainous areas without monitoring stations. In this study, we retrieved satellite remote sensing data for NO2, O3, and SO2 from the Ozone Monitoring Instrument (OMI) L3 products. Together with ground measurements (air monitoring stations and meteorological and land use data), we estimated the monthly NO2, O3, and SO2 concentrations with a spatial resolution of 3×3 km across Taiwan from 2005 to 2019. A three-stage estimation procedure was utilized: in Stage 1, an ensemble generalized additive model (GAM) and machine learning method were used to determine the spatiotemporal variations; in Stage 2, the remote sensing data were downscaled; and in Stage 3, the downscaled concentrations were reused in the Stage 1 procedure for fine-tuning estimations. We obtained overall leave-one-out cross-validation (LOOCV) R2 values ranging from 0.927-0.950, 0.704-0.721, and 0.601-0.716, and root-mean-square-errors (RMSEs) ranging from 1.59-2.28, 3.81-4.18, and 0.67-1.32 ppb for NO2, O3, and SO2, respectively, via the random forest procedure. The annual NO2 and SO2 concentrations greatly improved from 2005-2019, especially in the western residential area of Taiwan. However, despite these improvements in air quality, the annual O3 concentrations tended to increase from 2015–2019. This might be due to the complex mixtures of precursors (e.g., NO2), atmospheric circulation, barriers of the Central Mountain Ridge, and increasing ground temperatures over the past decade. The proposed multistage estimation procedure performed well over the whole island with complex terrain and topography. The study outcomes may provide epidemiological information for long-term ambient exposure estimates and guidance for future administrative policies.

Wireless Sensing Network for Implementation of Air Quality Monitoring System and Indoor Air Quality Index Application

Indoor air quality significantly impacts respiratory health and mental activity. This study utilizes a wireless sensing network (WSN) based on the Internet of Things (IoT) to monitor indoor air quality, referred to as an indoor air quality monitoring system. The system was installed and applied on campus at the University of Baghdad. The present study aims to monitor air quality parameters continuously within laboratories. Carbon monoxide, sulfur dioxide, nitrogen dioxide, ammonia, and particulate objects are the pollutants chosen to be monitored by the installed system in this study. These pollutants were selected because they affect indoor facilities' comfort, health, and working conditions. Colored coded data was employed in the monitoring system; defined ranges for each pollutant were also integrated. Sensor nodes, wireless modules that connect to the IoT server, and user applications are the main components of the IAQMS system. LCDs, mobile applications, the ThingSpeak web server, and the LabView platform are examples of techniques used to present data collected by the system. Additionally, the system includes a notification function that alerts students and lab personnel when indoor air quality index IAQI values signal unhealthy indoor air quality. The proactive approach ensures a regulated standard for indoor air quality and pollutants.

Optimizing beet seed germination via dielectric barrier discharge plasma parameters

This study explores the synergistic effects of gas composition and electric field modulation on beetroot seed germination using dielectric barrier discharge (DBD) plasma. The investigation initially focuses on the impact of air plasma exposure on germination parameters, varying both voltage and treatment duration. Subsequently, the study examines how different gas compositions (argon, nitrogen, oxygen, and carbon dioxide) affect germination outcomes under optimal air plasma conditions. Results indicate that plasma treatment significantly enhances germination rates and seedling growth relative to untreated controls. Notably, plasma exposure alters seed surface morphology and chemistry, increasing roughness, porosity, and hydrophilicity due to the formation of new polar functional groups. The highest germination rate (a 54.84 % increase) and germination index (a 40.11 % increase) were observed at the lowest voltage and shortest duration, whereas higher voltages and prolonged exposure reduced germination, likely due to oxidative stress. Among the tested gas environments, air plasma was most effective in enhancing water uptake and electrical conductivity, while oxygen plasma resulted in the highest germination index and marked improvements in root and shoot length. Conversely, carbon dioxide plasma treatment exhibited inhibitory effects on both germination and subsequent growth metrics. The results highlight the potential of DBD plasma technology to enhance agricultural productivity by optimizing seed germination and early growth. The study emphasizes the importance of precise parameter tuning, particularly gas composition and plasma exposure conditions, to maximize benefits while minimizing adverse effects, offering a refined approach to seed priming in agricultural practices.

Exposure to air pollutants and subclinical carotid atherosclerosis measured by magnetic resonance imaging: A cross-sectional analysis.

Long-term exposure to air pollution has been associated with higher risk of cardiovascular mortality. Less is known about the association of air pollution with initial development of cardiovascular disease. Herein, the association between low-level exposure to air pollutants and subclinical carotid atherosclerosis in adults without known clinical cardiovascular disease was investigated. Cross-sectional analysis within a prospective cohort study. The Canadian Alliance for Healthy Hearts and Minds Cohort Study; a pan-Canadian cohort of cohorts. Canadian adults (n = 6645) recruited between 2014-2018 from the provinces of British Columbia, Alberta, Ontario, Quebec, and Nova Scotia, were studied, for whom averages of exposures to nitrogen dioxide (NO2), ozone (O3), and fine particulate matter (PM2.5) were estimated for the years 2008-2012. Carotid vessel wall volume (CWV) measured by magnetic resonance imaging (MRI). In adjusted linear mixed models, PM2.5 was not consistently associated with CWV (per 5 μg/m3 PM2.5; adjusted estimate = -8.4 mm3; 95% Confidence Intervals (CI) -23.3 to 6.48; p = 0.27). A 5 ppb higher NO2 concentration was associated with 11.8 mm3 lower CWV (95% CI -16.2 to -7.31; p<0.0001). A 3 ppb increase in O3 was associated with 9.34 mm3 higher CWV (95% CI 4.75 to 13.92; p<0.0001). However, the coarse/insufficient O3 resolution (10 km) is a limitation. In a cohort of healthy Canadian adults there was no consistent association between PM2.5 or NO2 and increased CWV as a measure of subclinical atherosclerosis by MRI. The reasons for these inconsistent associations warrant further study.

Периоперационное кондиционирование оксидом азота для предотвращения острого почечного повреждения при кардиохирургических вмешательствах у пациентов с хронической болезнью почек: промежуточные результаты рандомизированного контролируемого исследования DEF

INTRODUCTION: Acute kidney injury (AKI) is a common and serious complication after cardiac surgery performed under cardiopulmonary bypass (CPB). Patients with chronic kidney disease (CKD) are particularly vulnerable to cardiac surgery-associated AKI. Nitric oxide (NO) has great potential for implementing multi-organ protection in cardiac surgery. OBJECTIVES: To test the hypothesis that perioperative nitric oxide conditioning has a good safety profile and reduces the incidence of acute kidney injury during cardiac surgery under cardiopulmonary bypass in patients with chronic kidney disease. MATERIAL AND METHODS: An interim analysis of the results of the single-center prospective randomized controlled trial DEFENDER was conducted. Currently, the study included 96 patients with CKD who underwent cardiac surgery under CPB. Patients was randomized into 2 equal groups consisting of 48 people each. In the experimental group, during the operation and 6 hours after it, 80 ppm NO was delivered through the ventilator and CPB circuits. In the control group, during the operation and 6 hours after it, a standard oxygen-air mixture without NO was delivered through the ventilator and CPB circuits. The end points of the study were: the difference between groups in the incidence of AKI, the incidence of postoperative complications, outcomes and the safety profile of NO therapy. RESULTS: In the experimental group, the incidence of AKI was significantly lower compared to the control group (16,7 и 35,4 %, p = 0.036). In the experimental group, nitrogen dioxide concentration in the gas-air mixture and methemoglobin level were not above the reference range. The groups did not differ in the frequency of blood transfusions, the amount of postoperative bleeding, or the number of platelets on the first day after surgery. CONCLUSIONS: Perioperative nitric oxide conditioning has a good safety profile and reduces the incidence of acute kidney injury during cardiac surgery with CPB in patients with chronic kidney disease.

Associations of exposure to outdoor PM2.5 and NO2 during pregnancy with childhood asthma, rhinitis, and eczema in a predominantly rural French mother-child cohort

Uncertainty remains regarding the effects of outdoor air pollution in rural areas on childhood asthma, rhinitis, and eczema. Although these diseases often coexist, few studies have examined the effects of air pollution on their multimorbidity. The objective of this study was to investigate the associations of pregnancy exposure to outdoor fine particulate matter (PM2.5) and nitrogen dioxide (NO2) with childhood asthma, rhinitis, eczema, and their multimorbidity. We included children from the 6-year (n = 1322) and 12-year (n = 1118) follow-up of the Pélagie mother-child cohort in Brittany, France where 64% of the participants lived in rural areas. Asthma, rhinitis, eczema, and a multimorbidity phenotype (concomitant presence of ≥2 diseases) were defined by validated questionnaires. PM2.5 and NO2 concentrations during pregnancy were modeled at residential address using land use regression. We assessed associations using logistic regressions per interquartile range (PM2.5: 3 μg/m3; NO2: 10 μg/m3). We also performed stratification by type of area (urban and rural). Asthma, rhinitis, eczema, and the multimorbidity phenotype prevalence were 12%, 20%, 22% and 12% at 6-years, and 10%, 23%, 19% and 11% at 12-years of follow-up. At 6-years, for eczema, a tendency of an association was observed with NO2 (OR = 1.15, 95% CI = 0.97–1.36, p-value = 0.10), and stratification by type of area showed statistically significant associations for PM2.5 (1.49 (1.03–2.13), p = 0.03) and NO2 (1.40 (1.08–1.82), p = 0.01) in the urban stratum. At 12-years, main analyses showed a tendency of associations of PM2.5 (1.38 (0.98–1.93), p = 0.07) and NO2 (1.25 (0.98–1.59), p = 0.07) with asthma, and of NO2 with the multimorbidity phenotype (1.23 (0.97–1.56), p = 0.09). While overall results were not statistically significant, associations in urban settings were stronger than in rural ones at 6-years suggesting that possible differences between the effects in urban and rural areas should be further explored.

Flexible and highly selective NO2 gas sensor based on direct-ink-writing of eco-friendly graphene oxide for smart wearable application

Nitrogen dioxide (NO2) is a major cause of respiratory disorders in outdoor and indoor environments. Real-time NO2 monitoring using nonintrusive wearable devices can save lives and provide valuable health data. This study reports a room-temperature, wearable, and flexible smart NO2 gas sensor fabricated via cost-effective printing technology on a polyimide substrate. The sensor uses alkali lignin with edge-oxidised graphene oxide (EGO-AL) ink, demonstrating a sensitivity of 1.70% ppm⁻1 and a detection limit of 12.70 ppb, with excellent selectivity towards NO2. The high sensing properties are attributed to labile oxygen functional groups from GO and alkali lignin, offering abundant interacting sites for NO2 adsorption and electron transfer. The sensor fully recovers to the baseline after heat treatment at 150 °C, indicating its reusability. Integration into lab coats showcased its wearable application, utilising a flexible printed circuit board to wirelessly alert the wearer via cell phone to harmful NO2 levels (>3 ppm) in the environment. This smart sensing application underscores the potential for practical, real-time air quality monitoring, personal safety enhancement, and health management.