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Biomass burning serves as important sources of volatile organic compounds (VOCs), yet our understanding of the molecular characteristics of oxygenated volatile organic compounds (OVOCs) from fresh emissions remains limited. In this study, gaseous organic compounds in fresh smokes from burning typical Chinese crop straws and woods are measured using an iodide time‐of‐flight chemical ionization mass spectrometer. Approximately 750 molecular formulas are identified, with CHO compounds containing carbon, hydrogen and oxygen atoms accounting for 77%–95% of the total. C1–C3 organic acids and dicarboxylic acids dominate the total CHO signal intensities by 27%–48%, while well‐known molecular markers of biomass burning, such as monosaccharide, guaiacol and syringol derivatives, contribute 7%–17%. Notably, crop straw and wood burning emit a higher abundance of guaiacol than syringol derivatives by a factor of 5. Additionally, a variety of nitrogen‐containing compounds (mainly in the CHON group) is identified, including isocyanate, amide, amino acids, and pyridine. The mass spectral profiles of organic compounds are largely similar between crop straw and wood burning fuels, although wood burning produces higher contributions of compounds with carbon atoms numbers >10. The saturation concentrations of organic compounds are estimated using molecular formula‐based volatility parameterization, revealing that semi‐volatile and intermediate VOCs (S/intermediate volatility organic compounds (IVOCs)) predominate smoke releases by 35%–60% and 20%–43%, respectively, with only a small fraction of low‐volatility compounds. Given the widespread nature of biomass burning in winter China, our results may have significant implications for interpreting secondary organic aerosol formation through gas‐particle partitioning or aqueous‐phase reactions. Plain Language Summary: Biomass burning is a significant source of volatile organic compounds (VOCs), with oxygenated volatile organic compounds (OVOCs) being particularly important due to their high reactivity and their contribution to the radical budget and secondary products formation. However, previous research has primarily focused on a limited number of OVOCs species from pine, spruce, and other biofuels, leading to insufficient studies on the full mass spectra of OVOCs from biomass smokes. Our study has addressed this gap by identifying approximately 750 OVOCs from burning typical Chinese crop straws and woods. We found that C1–C3 organic acids and dicarboxylic acids are the predominant contributors to total signal intensities. This expands on previous studies that have focused on a limited well‐known molecular markers of biomass burning, such as monosaccharide, guaiacol and syringol derivatives, and reveals the presence of nitrogen‐containing compounds, including isocyanate, amide, amino acids, and pyridine. The saturation concentrations of organic compounds are estimated, highlighting the importance of semi‐volatile and intermediate VOCs (S/IVOCs) in fresh smoke releases. Our study contributes to a better understanding of complex chemistry of biomass burning and its impact on air quality. It will serve as a crucial basis for accurately assessing biomass burning related‐secondary organic aerosol formation. Key Points: C1–C3 organic acids and dicarboxylic acids dominate the total signal intensities of fresh crop straw and wood burning emissionsThe mass spectral profiles are largely similar across different fuels, with wood burning produces higher contributions of large compoundsSemi‐volatile and intermediate volatile organic compounds predominate fresh smoke emissions, with only a small fraction of low‐volatility compounds [ABSTRACT FROM AUTHOR]

Precipitation is a critical factor in changing aerosol life cycle, yet its impact on aerosol species with different properties in megacities remains unclear. Here we characterized the changes of PM2.5 aerosol species during rainfall processes in five summers (2018–2022) in Beijing using highly time‐resolved measurements of aerosol chemical speciation monitor along with precipitation. Average pattern of 233 rainfall processes showed that over 30% decreases in aerosol species before rain start were due to the increased wind speed, and the subsequent decreases were caused by the combined effects of precipitation and winds with an average scavenging of 62%–100% in 1 hr. We also observed very different responses of aerosol species to precipitation depending on intensities, duration and formation mechanisms. During the rainfall processes, aerosol composition showed decreased contributions of organics and sulfate, particularly from late night to morning, while increased contributions of nitrate and chloride due to enhanced gas‐particle partitioning associated with the increase of relative humidity and the decrease of temperature. The scavenging rates of aerosol species significantly increased as the increase of rainfall intensity (>5 mm hr−1) and duration (>4 hr). However, the scavenging effect of light rainfall was negligible although the cumulative contribution was ∼50% due to high frequency, and even caused increases in nitrate and chloride. The case analysis of aerosol evolution during weak and heavy rainfall events further illustrated the dual impacts of precipitation on aerosol species through wet scavenging and secondary formation. Plain Language Summary: Wet scavenging is one of the most important pathways to clean up aerosol particles in the atmosphere, yet its impact on aerosol species in megacities remains unclear. By analyzing the highly time‐resolved measurements of aerosol composition and precipitation in five summers in Beijing, we found that over 30% decreases in aerosol species before rain start were due to the increased wind speed, and the subsequent decreases were caused by the combined effects of precipitation and winds with an average scavenging of 62%–100% in 1 hr. These results have significant implications that previous studies may overestimate the wet scavenging efficiency substantially without considering the effects of winds. Also, the responses of aerosol species to precipitation were largely different depending on intensities, duration and formation mechanisms. Aerosol composition showed decreased contributions of organics and sulfate while increased contributions of nitrate and chloride due to enhanced gas‐particle partitioning. Although the scavenging effect of light rain was negligible, the total scavenging of aerosol species was comparable to that of heavy rainfall due to high frequency. Our results shed new insights into the dual effects of precipitation in air pollution in summer depending on rainfall intensity, duration, and chemical properties of aerosol species. Key Points: Over 30% decreases in aerosol species before rain start were due to the increased wind speedLight and short rainfall scavenges aerosol species negligibly but promotes nitrate formation for single rainfall processThe cumulative contribution to scavenging effect by light rainfall is comparable to heavy rainfall due to its high frequency [ABSTRACT FROM AUTHOR]

Mitochondrial biogenesis is the process of generating new mitochondria to maintain cellular homeostasis. Here, we report that viruses exploit mitochondrial biogenesis to antagonize innate antiviral immunity. We found that nuclear respiratory factor‐1 (NRF1), a vital transcriptional factor involved in nuclear‐mitochondrial interactions, is essential for RNA (VSV) or DNA (HSV‐1) virus‐induced mitochondrial biogenesis. NRF1 deficiency resulted in enhanced innate immunity, a diminished viral load, and morbidity in mice. Mechanistically, the inhibition of NRF1‐mediated mitochondrial biogenesis aggravated virus‐induced mitochondrial damage, promoted the release of mitochondrial DNA (mtDNA), increased the production of mitochondrial reactive oxygen species (mtROS), and activated the innate immune response. Notably, virus‐activated kinase TBK1 phosphorylated NRF1 at Ser318 and thereby triggered the inactivation of the NRF1‐TFAM axis during HSV‐1 infection. A knock‐in (KI) strategy that mimicked TBK1‐NRF1 signaling revealed that interrupting the TBK1‐NRF1 connection ablated mtDNA release and thereby attenuated the HSV‐1‐induced innate antiviral response. Our study reveals a previously unidentified antiviral mechanism that utilizes a NRF1‐mediated negative feedback loop to modulate mitochondrial biogenesis and antagonize innate immune response. Synopsis: Mitochondrial damage, which can occur during viral infection, results in the release of damage‐associated molecular patterns (DAMPs) and can drive innate antiviral immunity via multiple pathways. Here, inhibition of NRF1‐mediated mitochondrial biogenesis was found to aggravate virus‐induced mitochondrial damage and promote innate antiviral immunity by enhancing mitochondrial DAMPs release.RNA and DNA viral infection activates NRF1‐mediated mitochondrial biogenesis in mouse and human immune cells.Deficiency of NRF1‐mediated mitochondrial biogenesis enhanced innate antiviral response in mice.Mitochondrial DAMPs, promoted by NRF1 deficiency, contribute to innate antiviral immunity.TBK1‐induced NRF1 phosphorylation is physiologically important to host antiviral response. [ABSTRACT FROM AUTHOR]

Photochemical aging is a key atmospheric processing, yet the changes in physicochemical properties of organic aerosol (OA) during photochemical aging of primary emissions from cooking and burning are less understood. Here we conducted 12 burning (straw, wood, and coal) and cooking experiments to characterize the evolution of size distributions, volatility, and glass transition temperature (Tg) from fresh smoke to aged OA with an equivalent photochemical age of ∼1.5 days using an oxidation flow reactor‐thermodenuder‐aerosol mass spectrometer system. The mass spectra of OA showed significant changes during photochemical aging, for example, the rapid degradation of m/z 60 for straw and wood burning OA, and the large increase in f44 (fraction of m/z 44 in OA) for all OA. The contributions of non‐volatile compounds to the total OA in aged burning OA (1.6%–5.3%) decreased considerably compared with those in fresh burning smoke (2.3%–17.1%), suggesting that photochemical aging of primary emissions for ∼1.5 days produced more volatile secondary OA (SOA). Consistently, the pronounced formation of SOA below 150 nm was observed, and it showed more volatile properties than aged large particles. The Tg of OA under dry conditions (Tg,org) was estimated based on volatility distributions, and the results showed increased Tg,org during photochemical aging of biomass burning and coal combustion emissions, while decreased Tg,org for aged cooking OA. Overall, our results illustrate the different changes in size distributions, volatility, and Tg,org through photochemical aging of different primary emissions, which in turn affect their impacts on radiative forcing and human health. Plain Language Summary: The properties of organic aerosol (OA) from primary emissions can have rapid changes during photochemical aging, and hence affect the radiative forcing and health effects of OA. However, changes in physicochemical properties of OA during aging, for example, size distributions, volatility, and glass transition temperature (Tg), are less understood, particularly for the OA from different types of primary emissions. In this work, we characterized such changes in size distributions, volatility, and viscosity of OA from biomass burning, coal combustion, and cooking emissions during photochemical aging. We observed pronounced formation of secondary OA (SOA) below 150 nm after aging, which showed higher volatility than the aged larger OA particles. The aged biomass burning and coal combustion emissions showed lower volatilities and higher viscosities than fresh emissions. Our results demonstrate that the size distributions, volatility, and viscosity of OA in regions with high anthropogenic emissions can have significant changes in days and hence exert different climate and health effects. Key Points: The volatility and glass transition temperature of organic aerosol (OA) from primary emissions changed significantly during photochemical agingSecondary OA formed below 150 nm was more volatile than aged large particlesThe aged biomass burning and coal combustion emissions showed lower volatilities and higher viscosities than fresh emissions [ABSTRACT FROM AUTHOR]

Cardiac ischemia, hypoxia, arrhythmias, and heart failure share the common electrophysiological changes featured by the elevation of intracellular Ca2+ (Ca2+ overload) and inhibition of the inward rectifier potassium (IK1) channel. IK1 channel agonists have been considered a new type of anti‐arrhythmia and cardioprotective agents. We predicted using a drug repurposing strategy that tetramisole (Tet), a known anthelminthic agent, was a new IK1 channel agonist. The present study aimed to experimentally identify the above prediction and further demonstrate that Tet has cardioprotective effects. Results of the whole‐cell patch clamp technique showed that Tet at 1–100 μmol/L enhanced IK1 current, hyperpolarized resting potential (RP), and shortened action potential duration (APD) in isolated rat cardiomyocytes, while without effects on other ion channels or transporters. In adult Sprague–Dawley (SD) rats in vivo, Tet showed anti‐arrhythmia and anticardiac remodeling effects, respectively, in the coronary ligation‐induced myocardial infarction model and isoproterenol (Iso, i.p., 3 mg/kg/day, 10 days) infusion‐induced cardiac remodeling model. Tet also showed anticardiomyocyte remodeling effect in Iso (1 μmol/L) infused adult rat ventricular myocytes or cultured H9c2 (2‐1) cardiomyocytes. Tet at 0.54 mg/kg in vivo or 30 μmol/L in vitro showed promising protections on acute ischemic arrhythmias, myocardial hypertrophy, and fibrosis. Molecular docking was performed and identified the selective binding of Tet with Kir2.1. The cardioprotection of Tet was associated with the facilitation of IK1 channel forward trafficking, deactivation of PKA signaling, and inhibition of intracellular calcium overload. Enhancing IK1 may play dual roles in anti‐arrhythmia and antiventricular remodeling mediated by restoration of Ca2+ homeostasis. [ABSTRACT FROM AUTHOR]

Context: The previous studies showed that hypogonadotropic hypogonadism (HH) occurred commonly in men with type 2 diabetes. However, since all the cohorts tested were from American and European studies, the occurrence of HH/nongonadal illness (NGI) in Chinese populations is unclear. Objective: The study aimed to explore the occurrence of HH/NGI in Chinese men with type 2 diabetes. Furthermore, the correlative factors and predictors of hypogonadism were investigated. Design: We conducted a cross‐sectional study of 637 Chinese men with type 2 diabetes aged 20–75 years in our clinic. The prevalence of HH/NGI was investigated by measuring serum total testosterone (TT), sex hormone‐binding globulin (SHBG), luteinizing hormone (LH) and follicle‐stimulating hormone (FSH) in the enrolled subjects. Free testosterone (FT) was calculated by using SHBG and TT levels and hypogonadism was defined as TT lower than 10.4 nmol/L and calculated FT (cFT) lower than 0.225 nmol/L. The LH cut‐off value for defining HH/NGI was 9.4 mIU/ml. Results: The results suggested that 31.9% of male Chinese type 2 diabetes patients had hypogonadism and 26.5% of subjects in our cohort were determined as HH/NGI. The occurrence of hypogonadism was markedly correlated with body mass index (BMI). There was a significant association between TT, cFT and SHBG levels with BMI. TT levels are inversely correlated with BMI and homeostasis model assessment‐estimated insulin resistance (HOMA‐IR) while positively related with SHBG. The cFT levels were inversely correlated with age, LH, FSH, BMI and HOMA‐IR. Multiple regression analysis suggested that SHBG, BMI and HOMA‐IR were significant predictors of TT and cFT. Conclusion: Our present study offered the first evidence that the occurrence of HH/NGI in Chinese male type 2 diabetes was 26.5%. TT and cFT were significantly correlated with BMI, SHBG and HOMA‐IR in Chinese men with type 2 diabetes. [ABSTRACT FROM AUTHOR]

The vast rural areas often experience more severe haze pollution than megacities during wintertime in North China Plain (NCP), yet the sources and evolution processes of aerosol particles, particularly organic aerosol (OA) remain poorly understood. Here we conducted real‐time measurements of submicron aerosol (PM1) species using a high‐resolution aerosol mass spectrometer at a representative rural site in NCP in winter 2019. Our results showed the dominance of organics (36%) and nitrate in PM1 (22%) in 2019. Positive matrix factorization analysis illustrated similarly important primary sources from traffic emissions, coal combustion, and biomass burning, yet secondary OA (SOA) from photochemical and aqueous‐phase related processing exceeded primary OA (53% vs. 47%). Substantial decreases in primary species and considerable increases in nitrate and sulphate were observed since winter 2018, demonstrating enhanced secondary formation in winter 2019. OA composition changed significantly from clean period to fog events with the contribution of aqueous phase‐related oxygenated OA increasing from 6% to 44%, while the photochemical SOA decreased correspondingly from 51% to 19%. The size distributions of aerosol species also changed by shifting toward large sizes during fog events. Elemental analysis of OA and the Van Krevelen diagram (H/C vs. O/C) illustrated the different roles of photochemical and aqueous‐phase processing during daytime and nighttime, respectively, and aqueous‐phase processing is subject to the formation of organic compounds with high H/C and O/C ratios. The large differences in fog processing of submicron aerosol species between 2018 and 2019 due to different temperatures were also elucidated. Plain Language Summary: Air quality in megacities in North China Plain (NCP) has been improved significantly during the last decade, however, severe haze pollution events occur frequently in vast rural areas during wintertime. Recent studies have demonstrated stronger health impacts of aerosol particles in rural area than megacities, yet the composition, sources and evolution processes of aerosol particles, particularly organic aerosol (OA) in rural area in NCP remain poorly characterized. Here we have a comprehensive characterization of submicron aerosol species at a rural site in winter in NCP. We observed substantial decreases in primary species and considerable increases in nitrate and sulphate from 2018 to 2019 due to enhanced secondary formation and the decreases in primary emissions. We found similarly important primary sources from traffic emissions, coal combustion, and biomass burning in rural area. However, secondary OA (SOA) from photochemical and aqueous‐phase related processing exceeded primary OA. The aqueous‐phase related SOA increased significantly by up to 44% during fog events, while the photochemical SOA decreased correspondingly from 51% to 19%. The size distributions, elemental composition of OA, and Van Krevelen diagram further illustrated the different roles of photochemical and aqueous‐phase processing in secondary aerosol formation in rural area in NCP. Key Points: Primary organic aerosol (OA) was primarily from coal combustion, biomass burning and traffic emissions in rural North China Plain in winterAqueous phase‐related OA showed large increases during fog events, while photochemical secondary OA was important during non‐fog periodsAerosol composition showed significant changes from 2018 to 2019 due to enhanced secondary formation and changes in primary emissions [ABSTRACT FROM AUTHOR]

Unexpectedly frequent severe haze episodes were observed in Beijing during February–March in 2021 after two phases of clean air action plan (2013–2020), yet the causes remained unclear. Here, we conducted real‐time fine particle (PM2.5) composition measurements during January–March in 2021 using a time‐of‐flight aerosol chemical speciation monitor and an aethalometer and compared with those during the coronavirus disease (COVID‐19) period in 2020. Our results showed ubiquitously elevated concentrations of chloride, black carbon (BC), and primary organic aerosol (POA) in 2021, suggesting increased primary emissions during the post‐COVID‐19 period. By using the machine learning‐based random forest (RF) algorithm, we found largely different responses of aerosol changes to meteorology in different months. After decoupling the effects of meteorology, the PM2.5 changes from 2020 to 2021 were reduced from −35.6% to −29.0% in January, −24.1% to −4.5% in February, and +92.6% to +34.2% in March, respectively. Our results demonstrate the dominant roles of stagnant meteorology and secondary production in the formation of severe haze episodes in March 2021. In particular, we found that the compositions of observed and deweathered PM2.5 were fairly similar between 2020 and 2021, and the ratios of secondary OA to secondary inorganic aerosols were close. Our study indicates that decoupling the influence of meteorological conditions is of great importance for better evaluation of mitigating strategies of air pollution due to the large impact of meteorology on the changes in PM2.5 species particularly in a short period. Key Points: Unexpectedly severely haze episodes were observed in March 2021 in BeijingClear increases in primary emissions during the post‐COVID‐19 period in BeijingLargely different responses of aerosol species to meteorology in different months [ABSTRACT FROM AUTHOR]

The utility of elevational gradients as tools to test either ecological hypotheses and delineate elevation‐associated environmental factors that explain the species diversity patterns is critical for moss species conservation. We examined the elevational patterns of species richness and evaluated the effects of spatial and environmental factors on moss species predicted a priori by alternative hypotheses, including mid‐domain effect (MDE), habitat complexity, energy, and environment proposed to explain the variation of diversity. Last, we assessed the contribution of elevation toward explaining the heterogeneity among sampling sites. We observed the hump‐shaped distribution pattern of species richness along elevational gradient. The MDE and the habitat complexity hypothesis were supported with MDE being the primary driver for richness patterns, whereas little support was found for the energy and the environmental factors. [ABSTRACT FROM AUTHOR]

The calcium‐sensing receptor (CaSR) is involved in the pathophysiology of many cardiovascular diseases, including myocardial infarction (MI) and hypertension. The role of Calhex231, a specific inhibitor of CaSR, in myocardial fibrosis following MI is still unclear. Using Wistar rats, we investigated whether Calhex231 ameliorates myocardial fibrosis through the autophagy‐NLRP3 inflammasome pathway in macrophages post myocardial infarction (MI). The rats were randomly divided into sham, MI and MI + Calhex231 groups. Compared with the sham rats, the MI rats consistently developed severe cardiac function, myocardial fibrosis and infiltration of inflammatory cells including macrophages. Moreover, inflammatory pathway including activation of NLRP3 inflammasome, IL‐1β and autophagy was significantly up‐regulated in myocardial tissue, infiltrated cardiac macrophages and peritoneal macrophages of the MI rats. These impacts were reversed by Calhex231. In vitro, studies revealed that calindol and rapamycin exacerbated MI‐induced autophagy and NLRP3 inflammasome activation in peritoneal macrophages. Calhex231 and 3‐Methyladenine (a specific inhibitor of autophagy) attenuated both autophagy and NLRP3 inflammasome activation; however, the caspase‐1 inhibitor Z‐YVAD‐FMK did not. Our study indicated that Calhex231 improved cardiac function and ameliorated myocardial fibrosis post MI, likely via the inhibition of autophagy‐mediated NLRP3 inflammasome activation; this provides a new therapeutic target for ventricular remodelling‐related cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Lung cancer has the highest morbidity and mortality among all cancers. Discovery of early diagnostic and prognostic biomarkers of lung cancer can greatly facilitate the survival rate and reduce its mortality. In our study, by analyzing Gene Expression Omnibus and Oncomine databases, we found a novel potential oncogene uridine‐cytidine kinase 2 (UCK2), which was overexpressed in lung tumor tissues compared to adjacent nontumor tissues or normal lung. Then we confirmed this finding in clinical samples. Specifically, UCK2 was identified as highly expressed in stage IA lung cancer with a high diagnostic accuracy (area under the receiver operating characteristic curve > 0.9). We also found that high UCK2 expression was related to poorer clinicopathological features, such as higher T stage and N stage and higher probability of early recurrence. Furthermore, we found that patients with high UCK2 expression had poorer first progression survival and overall survival than patients with low UCK2 expression. Univariate and multivariate Cox regression analyses showed that UCK2 was an independent risk factor related with worse DFS and OS. By gene set enrichment analysis, tumor‐associated biological processes and signaling pathways were enriched in the UCK2 overexpression group, which indicated that UCK2 might play a vital role in lung cancer. Furthermore, in cytology experiments, we found that knockdown of UCK2 could suppress the proliferation and migration of lung cancer cells. In conclusion, our study indicated that UCK2 might be a potential early diagnostic and prognostic biomarker for lung cancer. [ABSTRACT FROM AUTHOR]

A series of CuO‐MnOx‐CeO2/γ‐Al2O3 catalysts in different ratios were synthesized by a sol‐gel method with the purpose of improving the low‐temperature denitration performance (loading a transition mental oxide (MnOx, CeO2) on a CuO/γ‐Al2O3 copper‐based catalyst). The denitration performance of a low‐temperature SCR under the condition of simulated flue gas was measured using the programmed heating method in the catalytic reaction efficiency evaluation system. The denitration efficiency of the 6 % CuO‐5 % MnOx‐10 % CeO2/γ‐Al2O3 catalytic particles was maintained at over 80 % within a temperature range of 100–200 °C. The catalysts were characterized by surface area analysis (BET), x‐ray diffraction (XRD), and scanning electron microscopy (SEM). The best surface structure characteristics include the 5 % MnOx + 10 % CeO2 loading capacity of the catalyst, which was indicated by a BET analysis. The catalyst surface structure characteristics were effectively promoted by the amount of CeO2 and MnO2 loading proved by the SEM analysis. The possible mechanisms involved in SCR denitration at a low temperature were also discussed. The experimental results revealed that the catalyst granule with perfect surface characteristics and pore features was successfully synthesized by the sol‐gel method. The denitration performances were restrained by 10 % of H2O and 800 mg · m−3 of SO2, indicating that SO2 and H2O have an inhibiting effect on NOx conversion. [ABSTRACT FROM AUTHOR]

Distinguishing structural isomers is a critical and challenging task for biotechnology, chemical industry, and environmental monitoring. Approaches currently available are limited in terms of selectivity and simplicity. In this paper, a highly sensitive organic field‐effect transistor (OFET) using the cyclopentadithiophene‐benzothiadiazole (CDT‐BTZ) copolymers as a semiconductor is presented for easy and selective detection of different families of structural isomers, as well as between different isomers within each family. High accuracy discrimination is achieved over a range of concentrations using only a single sensing parameter derived from the OFET characteristic transfer curve. As a reference, other homopolymer‐ and donor–acceptor copolymer‐based OFET sensors are examined but do not have an equivalent sensing performance to that of the CDT‐BTZ‐based OFETs. Investigating the link between isomer absorption and swelling, supramolecular order and energy levels of the active layer reveals a unique effect of each isomer on the energy bands of the semiconducting polymer.A highly‐sensitive donor‐acceptor copolymer cyclopentadithiophene‐benzothiadiazole (CDT‐BTZ) based organic field‐effect transistor (OFET) can simply and selectively detect multiple types of structural isomers at low ppm levels. This includes xylene isomers, ketones and aldehydes, such as heptanal and 3‐heptanone. Robust discrimination is obtained between different families as well as between the isomers within each family. [ABSTRACT FROM AUTHOR]

Abstract: Ammonium sulfate (AS) and ammonium nitrate (AN) are key components of urban fine particles. Both field and model studies showed that heterogeneous reactions of SO2, NO2, and NH3 on wet aerosols accelerated the haze formation in northern China. However, little is known on phase transitions of AS‐AN containing haze particles. Here hygroscopic properties of laboratory‐generated AS‐AN particles and individual particles collected during haze events in an urban site were investigated using an individual particle hygroscopicity system. AS‐AN particles showed a two‐stage deliquescence at mutual deliquescence relative humidity (MDRH) and full deliquescence relative humidity (DRH) and three physical states: solid before MDRH, solid‐aqueous between MDRH and DRH, and aqueous after DRH. During hydration, urban haze particles displayed a solid core and aqueous shell at RH = 60–80% and aqueous phase at RH > 80%. Most particles were in aqueous phase at RH > 50% during dehydration. Our results show that AS content in individual particles determines their DRH and AN content determines their MDRH. AN content increase can reduce MDRH, which indicates occurrence of aqueous shell at lower RH. The humidity‐dependent phase transitions of nitrate‐abundant urban particles are important to provide reactive surfaces of secondary aerosol formation in the polluted air. [ABSTRACT FROM AUTHOR]

Multi‐parametric sensing fabrics have the potential to lead a new generation of applications in a wide variety of fields. Nevertheless, the use of these devices in complex environments depends on the ability of the sensing fabrics to decouple between various stimuli co‐existing in a complex environment. Fabric backbones with dispersed single‐wall carbon nanotubes and molecularly modified gold nanoparticles in elastomer outerwear of styrene–ethylene–butylene–styrene for multifunctional detection of complex physical and chemical stimuli are presented. This feature of the fabric–elastomer structure endows time‐resolved insensitivity to strain; furthermore, it enables decoupling pressure/relative humidity from curving surfaces. It is also shown that applying incompatible regression models to the time‐resolved output signals gives excellent discrimination between various stimuli collected from a complex environment. [ABSTRACT FROM AUTHOR]