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Atmospheric fine-particle (PM2:5) pollution is frequently associated with the formation of particulate nitrate (pNO-3), the end product of the oxidation of NOx gases (NOCNO2) in the upper troposphere. The application of stable nitrogen (N) (and oxygen) isotope analyses of pNO-3 to constrain NOx source partitioning in the atmosphere requires knowledge of the isotope fractionation during the reactions leading to nitrate formation. Here we determined the δ15N values of fresh pNO-3 (δ15N-pNO-3) in PM2:5 at a rural site in northern China, where atmospheric pNO-3 can be attributed exclusively to biomass burning. The observed δ15N- pNO-3 (12:17±1:55 ; n D 8) was much higher than the N isotopic source signature of NOx from biomass burning (1:04±4:13). The large difference between δ15N-pNO-3 and δ15N-NOx (1(δ15N)) can be reconciled by the net N isotope effect ("N) associated with the gas-particle conversion from NOx to NO-3. For the biomass burning site, a mean "N.ε 1.δ15N)) of 10:99±0:74 was assessed through a newly developed computational quantum chemistry (CQC) module. "N depends on the relative importance of the two dominant N isotope exchange reactions involved (NO2 reaction with OH versus hydrolysis of dinitrogen pentoxide (N2O5) with H2O) and varies between regions and on a diurnal basis. A second, slightly higher CQC-based mean value for "N (15:33±4:90) was estimated for an urban site with intense traffic in eastern China and integrated in a Bayesian isotope mixing model to make isotope-based source apportionment estimates for NOx at this site. Based on the δ15N values (10:93±3:32; n D 43) of ambient pNO-3 determined for the urban site, and considering the location-specific estimate for "N, our results reveal that the relative contribution of coal combustion and road traffic to urban NOx is 32%±11% and 68%±11%, respectively. This finding agrees well with a regional bottom-up emission inventory of NOx. Moreover, the variation pattern of OH contribution to ambient pNO-3 formation calculated by the CQC module is consistent with that simulated by theWeather Research and Forecasting model coupled with Chemistry (WRF-Chem), further confirming the robustness of our estimates. Our investigations also show that, without the consideration of the N isotope effect during pNO-3 formation, the observed δ15N-pNO-3 at the study site would erroneously imply that NOx is derived almost entirely from coal combustion. Similarly, reanalysis of reported δ15N-NO-3 data throughout China and its neighboring areas suggests that NOx emissions from coal combustion may be substantively overestimated (by > 30%) when the N isotope fractionation during atmospheric pNO-3 formation is neglected. [ABSTRACT FROM AUTHOR]

Simple Summary: Triple-negative breast cancer (TNBC) is characterized by a quick and high rate of recurrence. The benefits from neo-adjuvant chemotherapy associated with anti-PDL1 have been shown to be efficient in this aggressive form of breast cancer. Ferroptosis inducers (erastin/RSL3) induced the upregulation of CD274 in TNBC cells. Basal and TNBC subtypes of breast cancers overexpressed CD274 conjointly with three ferroptosis drivers: TNFAIP3, IFNG and IDO1 (IDO1: inhibitory immune checkpoint). These tumors present higher levels of recurrence. A potential synergy of ferroptosis inducers with anti-PD-L1 immunotherapy is suggested in recurrent TNBC. (1) Background: Triple-negative breast cancer (TNBC) is a distinct subgroup of breast cancer presenting a high level of recurrence, and neo-adjuvant chemotherapy is beneficial in its therapy management. Anti-PD-L1 immunotherapy improves the effect of neo-adjuvant therapy in TNBC. (2) Methods: Immune-modulation and ferroptosis-related R-packages were developed for integrative omics analyses under ferroptosis-inducer treatments: TNBC cells stimulated with ferroptosis inducers (GSE173905, GSE154425), single cell data (GSE191246) and mass spectrometry on breast cancer stem cells. Clinical association analyses were carried out with breast tumors (TCGA and METABRIC cohorts). Protein-level validation was investigated through protein atlas proteome experiments. (3) Results: Erastin/RSL3 ferroptosis inducers upregulate CD274 in TNBC cells (MDA-MB-231 and HCC38). In breast cancer, CD274 expression is associated with overall survival. Breast tumors presenting high expression of CD274 upregulated some ferroptosis drivers associated with prognosis: IDO1, IFNG and TNFAIP3. At the protein level, the induction of Cd274 and Tnfaip3 was confirmed in breast cancer stem cells under salinomycin treatment. In a 4T1 tumor treated with cyclophosphamide, the single cell expression of Cd274 was found to increase both in myeloid- and lymphoid-infiltrated cells, independently of its receptor Pdcd1. The CD274 ferroptosis-driver score computed on a breast tumor transcriptome stratified patients on their prognosis: low score was observed in the basal subgroup, with a higher level of recurrent risk scores (oncotypeDx, ggi and gene70 scores). In the METABRIC cohort, CD274, IDO1, IFNG and TNFAIP3 were found to be overexpressed in the TNBC subgroup. The CD274 ferroptosis-driver score was found to be associated with overall survival, independently of TNM classification and age diagnosis. The tumor expression of CD274, TNFAIP3, IFNG and IDO1, in a biopsy of breast ductal carcinoma, was confirmed at the protein level (4) Conclusions: Ferroptosis inducers upregulate PD-L1 in TNBC cells, known to be an effective target of immunotherapy in high-risk early TNBC patients who received neo-adjuvant therapy. Basal and TNBC tumors highly expressed CD274 and ferroptosis drivers: IFNG, TNFAIP3 and IDO1. The CD274 ferroptosis-driver score is associated with prognosis and to the risk of recurrence in breast cancer. A potential synergy of ferroptosis inducers with anti-PD-L1 immunotherapy is suggested for recurrent TNBC. [ABSTRACT FROM AUTHOR]

(1) Background: Breast cancer is a frequent heterogeneous disorder diagnosed in women and causes a high number of mortality among this population due to rapid metastasis and disease recurrence. Ferroptosis can inhibit breast cancer cell growth, improve the sensitivity of chemotherapy and radiotherapy, and inhibit distant metastases, potentially impacting the tumor microenvironment. (2) Methods: Through data mining, the ferroptosis/extracellular matrix remodeling literature text-mining results were integrated into the breast cancer transcriptome cohort, taking into account patients with distant relapse-free survival (DRFS) under adjuvant therapy (anthracyclin + taxanes) with validation in an independent METABRIC cohort, along with the MDA-MB-231 and HCC338 transcriptome functional experiments with ferroptosis activations (GSE173905). (3) Results: Ferroptosis/extracellular matrix remodeling text-mining identified 910 associated genes. Univariate Cox analyses focused on breast cancer (GSE25066) selected 252 individual significant genes, of which 170 were found to have an adverse expression. Functional enrichment of these 170 adverse genes predicted basal breast cancer signatures. Through text-mining, some ferroptosis-significant adverse-selected genes shared citations in the domain of ECM remodeling, such as TNF, IL6, SET, CDKN2A, EGFR, HMGB1, KRAS, MET, LCN2, HIF1A, and TLR4. A molecular score based on the expression of the eleven genes was found predictive of the worst prognosis breast cancer at the univariate level: basal subtype, short DRFS, high-grade values 3 and 4, and estrogen and progesterone receptor negative and nodal stages 2 and 3. This eleven-gene signature was validated as regulated by ferroptosis inductors (erastin and RSL3) in the triple-negative breast cancer cellular model MDA-MB-231. (4) Conclusions: The crosstalk between ECM remodeling-ferroptosis functionalities allowed for defining a molecular score, which has been characterized as an independent adverse parameter in the prognosis of breast cancer patients. The gene signature of this molecular score has been validated to be regulated by erastin/RSL3 ferroptosis activators. This molecular score could be promising to evaluate the ECM-related impact of ferroptosis target therapies in breast cancer. [ABSTRACT FROM AUTHOR]

Chiang Mai, Thailand, has long experienced seasonal air pollution episodes at the end of the dry season (February-April). While the severity and length of the episodes vary annually, popular narratives describe how the "haze crisis" is worsening. In this article, we address the role of the media in driving the growing awareness of seasonal air pollution in Chiang Mai. The article contributes to scholarship on the politics of the representation of environmental problems and the understanding of discourses and practices through which natural phenomena are historically produced and become known. It takes into account social relations of power by addressing local environmental politics and how they are framed by politicaleconomic interests. Based on the analysis of three Thai national newspapers over a 25-year period as well as extensive fieldwork and interviews in Chiang Mai Province, we chronicle the development of a collective concern about seasonal air pollution and its political-ecological drivers and consequences. Finally, we demonstrate how this shared perception of a worsening haze crisis is driven by ongoing debates surrounding the use of forests, agro-capitalism, and legitimate forms of political power. This article contributes to emerging scholarship in environmental media studies that addresses how environmental changes become environmental crises. [ABSTRACT FROM AUTHOR]

The editorial board of JGR Atmospheres thanks reviewers who refereed papers in 2022. Plain Language Summary: The editorial board of JGR Atmospheres thanks reviewers who refereed papers in 2022. Key Point: The editors thank the 2022 peer reviewers [ABSTRACT FROM AUTHOR]

Air pollution has been recognized as a threat to human health since the time of Hippocrates, ca 400 BC. Successive written accounts of air pollution occur in different countries through the following two millennia until measurements, from the eighteenth century onwards, show the growing scale of poor air quality in urban centres and close to industry, and the chemical characteristics of the gases and particulate matter. The industrial revolution accelerated both the magnitude of emissions of the primary pollutants and the geographical spread of contributing countries as highly polluted cities became the defining issue, culminating with the great smog of London in 1952. Europe and North America dominated emissions and suffered the majority of adverse effects until the latter decades of the twentieth century, by which time the transboundary issues of acid rain, forest decline and ground-level ozone became the main environmental and political air quality issues. As controls on emissions of sulfur and nitrogen oxides (SO2 and NOx) began to take effect in Europe and North America, emissions in East and South Asia grew strongly and dominated global emissions by the early years of the twenty-first century. The effects of air quality on human health had also returned to the top of the priorities by 2000 as new epidemiological evidence emerged. By this time, extensive networks of surface measurements and satellite remote sensing provided global measurements of both primary and secondary pollutants. Global emissions of SO2 and NOx peaked, respectively, in ca 1990 and 2018 and have since declined to 2020 as a result of widespread emission controls. By contrast, with a lack of actions to abate ammonia, global emissions have continued to grow. This article is part of a discussion meeting issue 'Air quality, past present and future'. [ABSTRACT FROM AUTHOR]

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Background and aims: Nitrogen (N) is critical for zinc (Zn) uptake into plant roots, which promotes Zn accumulation and biofortification of grains in winter wheat (Triticum aestivum L.). However, little is known about the role of TaZIPs genes in the Zn uptake and translocation in response to N supply. This study explored a possible avenue to improve Zn uptake and translocation by adjusting N supply in winter wheat. Methods: Winter wheat (Triticum aestivum.cv Zhengmai379) was cultivated with low, medium and high N in a nutrition solution or a pot soil with or without Zn supply. Plants in hydroponic culture were harvested at 21 d after different treatments and those in the soil culture were harvested at grain filling stage, and N and Zn concentrations and accumulation, Zn translocation coefficient, and the expression of TaZIP3 and TaZIP7 in different tissues were determined. Results: When N supply was increased, Zn concentration and accumulation in shoot, Zn accumulation in whole plants, and root-to-shoot translocation of Zn were decreased in the solution without Zn supply. In the solution with Zn supply, increasing N supply increased Zn concentration in shoot, and medium N supply increased Zn accumulation in shoot and whole plants. Increasing N supply increased Zn concentration and accumulation in root, stem, leaf, glume and grain, and Zn translocation form root to stem, but decreased Zn translocation from stem to leaf, stem to glume and glume to grain under both Zn-deficient and Zn-sufficient conditions. Medium N supply up-regulated the expression of TaZIP3 and TaZIP7 in the roots of winter wheat cultured under both Zn-deficient and Zn-sufficient conditions. In Zn-deficient soil, the expression of TaZIP3 and TaZIP7 in root and glume was up-regulated but that in stem and leaf was down-regulated by increasing N supply. Medium or high N supply induced the expression of TaZIP3 and TaZIP7 in different tissues of winter wheat grown under Zn-sufficient condition. Conclusions: Adequate N supply improves the grain Zn concentration through enhancing Zn uptake and root-to-shoot translocation, which could be mediated by induced expression of TaZIP3 and TaZIP7 in roots of winter wheat. [ABSTRACT FROM AUTHOR]

Oroxylin A is a natural extract and has been reported to have a remarkable anticancer function. However, the mechanism of its anticancer activity remains not quite clear. In this study, we examined the inhibiting effects of Oroxylin A on breast cancer cell proliferation, migration, and epithelial-mesenchymal transition (EMT) and its possible molecular mechanism. The cytoactive and inflammatory factors were analyzed via Cell Counting Kit-8 assay and ELISA assay, respectively. Flow cytometry and western blotting were used to assess the cell proliferation. In addition, a wound healing assay and transwell assay were used to detect cell invasion and migration. qRT-PCR and western blot were employed to determine the effect of Oroxylin A on the EMT formation. Moreover, expression level of protein related to NF-κB signaling pathway was determined by western blot. The results revealed that Oroxylin A attenuated the cytoactivity of MDA-MB-231 cells in a dose- and a time-dependent manner. Moreover, cell proliferation, invasion, and migration of breast cancer cells were inhibited by Oroxylin A compared to the control. The mRNA and protein expression levels of E-cadherin were remarkably increased while N-cadherin and Vimentin remarkably decreased. Besides, Oroxylin A suppressed the expression of inflammatory factors and NF-κB activation. Furthermore, we also found that supplement of TNF-α reversed the effects of Oroxylin A on the cell proliferation, invasion, migration, and EMT in breast cancer cells. Taken together, our results suggested that Oroxylin A inhibited the cell proliferation, invasion, migration, and EMT through inactivating NF-κB signaling pathway in human breast cancer cells. These findings strongly suggest that Oroxylin A could be a therapeutic potential candidate for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Abstract Currently, haze events in winter occur more frequently than decades ago, especially in Eastern and Central China, including the Yangtze River Delta (YRD). WRF-Chem is applied in this study to explore the discrepancies of the simulated air pollutants induced by employing different emission inventories, particularly during haze events. Two inventories are involved in this study, MEIC (Multi-resolution Emission Inventory for China) and GlobEmission (inventory from GlobEmission project emission estimates), representing the emission inventories based on quite different ways. We first compared monthly emissions of SO 2 and NO x in two inventories during January over YRD, and found the mean differences of SO 2 (NO x) are 20% (7%), with the ranges of 0%–47% (−100%–100%). The largest differences are both found in Shanghai, with 47% for SO 2 (MEIC in 2010, GlobEmission in 2014), and 45% for NO x (MEIC in 2010, GlobEmission in 2015), respectively, partly because the reduction of emissions was large during the 12th Five-Year Plan (2011–2015) in this area. By comparing the simulated air pollutants mass concentrations using two inventories with in-situ observations during January 2015, we found that the simulated SO 2 using MEIC and GlobEmission are both higher than observations, with mean normalized biases of 207% and 121% over YRD, respectively, and much larger in the city cluster of Nanjing-Shanghai, where are nearly four (MEIC) and three times (GlobEmission) higher than observations. In contrast, NO 2 simulations using GlobEmission are lower than observations (22%) and MEIC simulations (45%) over YRD. The largest biases of GlobEmission simulation are found in Zhejiang province (over 70%). The biases of simulated monthly mean PM 2.5 are 38% (MEIC) and 30% (GlobEmission) over YRD, respectively. A case study during heavy haze event shows that the biases increase to 61% (MEIC) and 39% (GlobEmission), and spatial correlation coefficient in the simulation using GlobEmission increase to 0.69 over YRD. Temporal correlation coefficients in the city cluster of Nanjing-Shanghai increase from 0.5 (MEIC) to 0.7 (GlobEmission). Highlights • Emissions of SO 2 (NO x) in MEIC inventory are 20% (7%) higher than GlobE. • Simulated SO 2 (NO 2) are 207% (49%) in MEIC and 121% (−22%) in GlobE. than observed. • Simulated PM 2.5 are 38% (MEIC) and 30% (GlobE.) higher than observations. • Larger discrepancies (22%) of simulated PM 2.5 by two inventories are found in haze. • Temporal R of PM 2.5 is better from simulation with GlobE. (0.7) than with MEIC (0.5). [ABSTRACT FROM AUTHOR]

Secondary inorganic aerosols, including sulfate, nitrate, and ammonium (SNA), are the predominant components of fine particles (PM 2.5). Reasonable representations of SNA formation in numerical models can largely improve the predictions of PM 2.5 concentrations and effectively help implement emission control strategies. Despite the Atmospheric Pollution Prevention and Control Action Plan has been implemented since 2013, PM 2.5 concentration during 2017 in Nanjing, one of the megacities in China, still exceeded the World Health Organization-recommended safe level (35 μg m−3). In this study, WRF-Chem model was applied to simulate aerosol chemical components in PM 2.5 during April 2016 and January 2017 in Nanjing, and the simulations are evaluated with in-situ observations. Our results show that the model can reasonably reproduce the temporal variability of PM 2.5 in two seasons, but significantly underestimate the sulfate concentrations by 71% (84%) in April (January), and overestimate the nitrate concentrations by 67% (45%) in April (January). The simulated ammonium is overall consistent with the observations. Meanwhile, the model tends to overestimate SO 2 concentrations by 20% (74%) in April (January). Several sensitivity studies are conducted to explore the mechanisms for underestimation of sulfate and overestimation of nitrate, and found that the conversion rate of SO 2 to sulfate is significantly underestimated in the model. Tripling the gas-phase oxidation rate of SO 2 by OH only enhances sulfate by 67% (72%) in April (January), indicating gas-phase oxidation is not the main causes for the underestimations in the model. However, inclusion of SO 2 heterogeneous oxidation in aerosol water can largely increase the simulated sulfate by 84% (196%) in April (January), and also better reproduce the diurnal variations of sulfate compared to the reference run. It should be noted that the simulated sulfate is still 47% (53%) lower than the observations in April (January), though inclusion of heterogeneous reaction can substantially improve the simulation performance of SNA. • SO 4 underestimates by 71% (84%), while NO 3 overestimates by 45% (67%) in Apr. (Jan.). NH 4 is consistent with the observation. • Underestimated SO 4 is accompanied by overestimated SO 2 by 27% (74%) in Apr. (Jan.), indicating SO 2 oxidation rate may be low. • Compared to the reference run, tripling SO 2 gas-phase oxidation rate only increases SO 4 by 67% (72%) in Apr. (Jan.). • Incorporating SO 2 heterogeneous reaction in aerosol water can increase SO 4 y 84% (196%) in Apr. (Jan.). • Incorporating SO 2 heterogeneous reaction can also better reproduce the observed diurnal variation. [ABSTRACT FROM AUTHOR]