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Long-term trends of atmospheric compositions are significant for assessing the influence of human activities on the atmosphere and protecting the atmospheric environment. In this study, based on heavy metal concentrations and Pb isotope ratios in a well-dated sediment core from a remote alpine lake in central North China, anthropogenic fluxes of As, Cd, Sb, and Pb were reconstructed and heavy metal evolutions in the atmosphere were revealed in the last 200 years. The heavy metals in the atmosphere were generally natural origins before 1980 A.D. Since the 1980s they began to increase gradually, but they increased the most in the 1990s resulting from rapid developments of rough and high energy-consuming industries in North China. After entering the 21st century the industries still developed rapidly, but the atmospheric Pb ceased increase and the As and Sb even decreased in the 2000s due to (1) phasing out of leaded gasoline and (2) implementing stricter industrial emission standards in 2000 A.D. in China. However, in the 2000s the atmospheric heavy metals still kept at a relatively high level and even likely began to increase again in the 2010s. Considering the lake relatively remote and seldom affected by local human activities, the results likely reflect heavy metal evolutions in the regional background atmosphere of central North China at the annual/decadal timescale in the last 200 years. [ABSTRACT FROM AUTHOR]

Deferred revascularization of mildly stenotic coronary vessels based exclusively on physiological evaluation is associated with up to 5% residual incidence of future adverse events at 1 year. We aimed to evaluate the incremental value of angiography-derived radial wall strain (RWS) in risk stratification of non–flow-limiting mild coronary narrowings. This is a post hoc analysis of 824 non–flow-limiting vessels in 751 patients from the FAVOR III China (Comparison of Quantitative Flow Ratio Guided and Angiography Guided Percutaneous Intervention in Patients With Coronary Artery Disease) trial. Each individual vessel had ≥1 mildly stenotic lesion. The primary outcome was vessel-oriented composite endpoint (VOCE), defined as the composite of vessel-related cardiac death, vessel-related myocardial infarction (nonprocedural), and ischemia-driven target vessel revascularization at 1-year follow-up. During 1-year follow-up, VOCE occurred in 46 of 824 vessels, with a cumulative incidence of 5.6%. Maximum RWS (RWS max) was predictive of 1-year VOCE with an area under the curve of 0.68 (95% CI: 0.58-0.77; P < 0.001). The incidence of VOCE was 14.3% in vessels with RWS max >12% vs 2.9% in those with RWS max ≤12%. In the multivariable Cox regression model, RWS max >12% was a strong independent predictor of 1-year VOCE in deferred non–flow-limiting vessels (adjusted HR: 4.44; 95% CI: 2.43-8.14; P < 0.001). The risk of deferred revascularization based on combined normal RWS max and Murray–law-based quantitative flow ratio (μQFR) was significantly reduced compared with μQFR alone (adjusted HR: 0.52; 95% CI: 0.30-0.90; P = 0.019). Among vessels with preserved coronary flow, angiography-derived RWS analysis has the potential to further discriminate vessels at risk of 1-year VOCE. (Comparison of Quantitative Flow Ratio Guided and Angiography Guided Percutaneous Intervention in Patients With Coronary Artery Disease [FAVOR III China Study]; NCT03656848) [Display omitted] [ABSTRACT FROM AUTHOR]

• High platelet reactivity and gastric mucosal injury after aspirin (ASA) treatment compromise clinical efficacy. • Adding Panax notoginseng saponin (PNS) to ASA potentiates platelet inhibition without increased bleeding. • PNS alleviates ASA-related dyspepsia symptoms and mitigates ASA-induced gastric mucosal injury. • These effects are associated with intraplatelet and gastric arachidonic acid metabolism modulation by lipidomic analysis. High platelet reactivity and gastric mucosal injury after aspirin (ASA) treatment are associated with poor compliance and an increased risk of cardiovascular events. Panax notoginseng saponins (PNS) have been widely used for the treatment of coronary heart disease (CHD) in addition to antiplatelet drugs in China; however, the joint effect and possible mechanism of PNS in addition to ASA on platelet activation and gastric injury remain unclear. This study was designed to investigate the combinational effects of PNS with ASA, and to explore the underlying mechanism via arachidonic acid (AA) metabolism pathway using lipidomic analysis. In a randomized, assessor-blinded trial, 42 patients with stable coronary heart disease (SCHD) and chronic gastritis were randomly assigned to receive ASA (n = 21) or PNS + ASA (n = 21) for 2 months. Compared with ASA alone, PNS + ASA further inhibited CD62p expression, GPIIb-IIIa activation and platelet aggregation and led to increased platelet inhibition rate. PNS + ASA suppressed the activity of platelet cyclooxygenase (COX)-1, and decreased the production of TXB 2 , PGD 2 , PGE 2 , 11-HETE, the downstream oxylipids of AA/COX-1 pathway in platelets, compared with ASA alone. The severity of dyspepsia assessment (SODA) results showed that patients in PNS + ASA group exhibited relieved dyspeptic symptoms as compared with those in ASA group, which might be associated with enhanced secretion of gastrin and motilin. In vivo study of myocardial infarction rats demonstrated that PNS attenuated ASA-induced gastric mucosal injury, which was related to markedly boosted gastric level of 6,15-diketo-13,14-dihydro-prostaglandin (PG)F1α, 13,14-dihydro-15-keto-PGE 2 and PGE 2 from AA/PG pathway in response to PNS + ASA compared with ASA alone. In summary, our study demonstrated that the combination of PNS and ASA potentiated the antiplatelet effect of ASA via AA/COX-1/TXB 2 pathway in platelets, and mitigated ASA-related gastric injury via AA/PG pathway in gastric mucosa. [ABSTRACT FROM AUTHOR]

• Long-term environmental changes of Lake Baiyangdian are spatially heterogeneous. • Hydrological process and land use together lead to the spatial heterogeneities. • Major environmental transitions of the wetland occurred in the 1960 s and 1990 s. • Humulus pollen is a key indicator of anthropogenic impacts in populated wetland. Understanding long-term environmental changes and man-land interactions within wetlands is important for their ecological maintenance and restoration. However, there has been little focus on the spatial heterogeneity of environmental variations of wetlands, especially large agricultural wetlands, which hinders the development of targeted management programs for specific areas. We conducted a multi-proxy study of the sediments of a typical agricultural wetland, Lake Baiyangdian in North China, to assess the spatial heterogeneity of environmental changes over the past 70 years. The results reveal that the environmental changes in Lake Baiyangdian were spatially heterogeneous, mainly reflected by the response to hydrological variations before the 1970 s, and by changes in trophic level and land cover transitions since the 1990 s, which are strongly linked to changes in agricultural land use. Pollen and grain-size analyses revealed the large-scale spatial heterogeneity of changes in the sedimentary environment. Areas with greater openness, shallower water depths, and proximity to inflowing rivers were generally more sensitive to hydrological processes and provided regional records of environmental change. In contrast, populated areas far from inflows tended to capture more local changes related to anthropogenic impacts. Intensive agricultural activity has led to a continuous increase in nutrient enrichment and significant land cover transitions in Lake Baiyangdian, mainly the loss of natural wetland. Variations in Humulus pollen were a key indicator of these anthropogenic impacts. Hydrological processes and land use changes were together responsible for the spatial heterogeneity of the environmental variations in Lake Baiyangdian over the last 70 years, indicating the dominant role of human impacts on the spatio-temporal pattern of the evolution of this wetland ecosystem, and the complexity of its environmental management. [ABSTRACT FROM AUTHOR]

Abstract: Independent dust provenance data play an important role in understanding changes in the atmospheric dust loading over geological time. Major elemental compositions and grain-size characteristics of the aeolian deposits (Xiangshan (XS) section) at the southeastern margin of the Tengger Desert in northwestern China demonstrate that the deposits are an intermediate product of the transportation of aeolian materials from the dust source area (deserts) to the dust depositional regions (Chinese Loess Plateau) that were likely formed by dust storm processes. The >40μm and 63–178μm fractions and the ratio of SiO2/TiO2 of the XS section were used as proxies to reconstruct the surface wind regime over the last 20kyr. The results show that the surface winds were much stronger and fluctuate acutely from 19.1 to 11.4kyr. The winds gradually attenuated after the beginning of the Holocene and reached a minimum between 4.0 and 3.5kyrBP. A sharp increase in surface winds occurred after 2.5kyrBP. The surface winds in the Asian dust source area are largely consistent with the changes in winter monsoon strength documented by the Chinese loess deposits. Also, the stronger surface winds from 19.1 to 11.4kyr coincide with the high mineral dust concentration determined from the Greenland ice core, except for the period of Bölling–Allerød (B/A), when the atmospheric dust may have been washed out by enhanced global hydrological cycles although dust was still emitted from source areas. This suggests that the stronger surface winds in dust source areas can enhance the atmospheric dust loadings during the late glacial. The weakening surface wind regime during the Holocene may have greatly contributed to the decrease in dust concentration of the remote dust records. The paleo-environmental changes in the study area since 42.5kyrBP are broadly in agreement with other adjacent records. However, the possible warm and humid spell of 42.5–19.1kyrBP still requires verification. [Copyright &y& Elsevier]