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Surface ozone (O3) and fine particulate matter (PM2.5) are dominant air pollutants in China. Concentrations of these pollutants can show significant differences between urban and nonurban areas. However, such contrast has never been explored on the country level. This study investigates the spatiotemporal characteristics of urban-to-suburban and urban-to-background difference for O3 (Δ[O3]) and PM2.5 (Δ[PM2.5]) concentrations in China using monitoring data from 1171 urban, 110 suburban, and 15 background sites built by the China National Environmental Monitoring Center (CNEMC). On the annual mean basis, the urban-to-suburban Δ[O3] is −3.7 ppbv in Beijing-Tianjin-Hebei, 1.0 ppbv in the Yangtze River Delta, −3.5 ppbv in the Pearl River Delta, and −3.8 ppbv in the Sichuan Basin. On the contrary, the urban-to-suburban Δ[PM2.5] is 15.8, −0.3, 3.5 and 2.4 µg m−3 in those areas, respectively. The urban-to-suburban contrast is more significant in winter for both Δ[O3] and Δ[PM2.5]. In eastern China, urban-to-background differences are also moderate during summer, with −5.1 to 6.8 ppbv for Δ[O3] and −0.1 to 22.5 µg m−3 for Δ[PM2.5]. However, such contrasts are much larger in winter, with −22.2 to 5.5 ppbv for Δ[O3] and 3.1 to 82.3 µg m−3 for Δ[PM2.5]. Since the urban region accounts for only 2% of the whole country’s area, the urban-dominant air quality data from the CNEMC network may overestimate winter [PM2.5] but underestimate winter [O3] over the vast domain of China. The study suggests that the CNEMC monitoring data should be used with caution for evaluating chemical models and assessing ecosystem health, which require more data outside urban areas.

Isoprene is a key biogenic volatile organic compound of vital importance for global climate change and air quality. Previous studies projecting future changes of isoprene emissions showed a wide range of uncertainties due to the discrepancies in emission schemes, climate models, and future scenarios. Here, we use an ensemble of models from the Coupled Model Intercomparison Project version 6 (CMIP6) to explore the spatiotemporal variations of global isoprene emissions at present day and their changes by the end of 21st century. At present day, most models predict similar emission rates of 400 Tg C yr−1 but with large differences in the long-term trends. For models using the scheme of Model of Emissions of Gases and Aerosols from Nature, isoprene emissions show limited changes during historical period but significant enhancements after the year 2000. However, for models using another scheme with strong CO2 inhibition effects, isoprene emissions show decreasing trends during historical period and moderate increasing trends after the year 2000. By the end of 21st century, the ensemble projection shows increases of 21–57% in isoprene emissions with the largest enhancement for the strongest warming scenario. Attribution shows that temperature is the dominant driver for the increase of isoprene emissions, no matter whether the CO2 inhibition effects are considered or not. The enhanced isoprene emissions increase the risks of ozone pollution in a warmer climate.

C1qTNF-related protein 1 (CTRP1) is independently associated with type 2 diabetes. However, the relationship between CTRP1 and insulin resistance is still not established. This study aimed to explore the role of CTRP1 under the situation of insulin resistance in adipose tissue. Plasma CTRP1 level was investigated in type 2 diabetic subjects (n = 35) and non-diabetic subjects (n = 35). The relationship between CTRP1 and phosphorylation of multi insulin receptor substrate 1 (IRS-1) serine (Ser) sites was further explored. Our data showed that Plasma CTRP1 was higher and negative correlation with insulin resistance in diabetic subjects (r = -0.283, p = 0.018). Glucose utilisation test revealed that the glucose utilisation rate of mature adipocytes was improved by CTRP1 in the presence of insulin. CTRP1 was not only related to IRS-1 protein, but also negatively correlated with IRS-1 Ser1101 phosphorylation (r = -0.398, p = 0.031). Furthermore, Phosphorylation levels of IRS-1 Ser1101 were significantly lower after incubation with 40 ng/mL CTRP1 in mature adipocytes than those with no intervention (p < 0.05). There was no significant correlation between CTRP1 and other IRS-1 serine sites (Ser302, Ser307, Ser612, Ser636/639, and Ser789). Collectively, our results suggested that CTRP1 might improve insulin resistance by reducing the phosphorylation of IRS-1 Ser1101, induced in the situation of insulin resistance as a feedback adipokine.

The present study aimed to investigate the association between insulin resistance (IR), nitric oxide (NO) production and myocardial apoptosis in a background of coexisting hypertension in a rodent animal model. A hypertensive rat model was established by feeding Wistar and spontaneously hypertensive rats (SHR) with a high sucrose/fat (HSF) diet for 12 weeks, in conjunction with isosorbide mononitrate (ISMN). Increased IR, NO content, apoptotic gene and protein expression, and morphological alterations within rat myocardium were evaluated. Following a total of 12 weeks of feeding with HSF and ISMN resulted in increased IR and NO content within the myocardial tissue of Wistar and SHR rats. HSF and ISMN activated myocardial apoptosis by downregulating the gene transcription and protein expression levels of the anti‑apoptotic B‑cell lymphoma 2 (Bcl‑2), and increasing the pro‑apoptotic Bcl‑2 associated X protein. Apoptosis was demonstrated by DNA fragmentation in terminal deoxynucleotidyl‑transferase‑mediated dUTP nick end labelling assay. In all experiments, the combination of HSF and ISMN was associated with more pronounced effects, indicating the possible synergistic effects. In addition, the correlation analysis in the Wistar rats fed with HSF only, revealed a positive association between NO production and IR. The results of the present study indicated that HSF and ISMN simultaneously increased IR, NO production and myocardial apoptosis in the hypertensive rat model, and may therefore contribute to investigations into the long‑term clinical use of ISMN in hypertensive patients.

Single-phase bulk Ti 2 AlN was prepared by spark plasma sintering (SPS) at 1200 °C of Ti/Al/TiN powders in stoichiometric proportion. Investigated by X-ray diffraction (XRD) of samples and the sintering process parameter, the reaction procedure could be analyzed. Scanning electron microscopy (SEM) and electron probe micro-analysis (EPMA) coupled with energy-dispersive spectroscopy (EDS) were utilized to investigate the morphology characteristics. When sintered at 1200 °C, Ti 2 AlN phase was well developed with a close and lamellated structure. The distribution of Ti 2 AlN grains was homogeneous.

The aim of this work was to investigate interactions of the human ether-a-go-go channel heag2 with human brain proteins. For this, we used heag2-GST fusion proteins in pull-down assays with brain proteins and mass spectrometry, as well as coimmunoprecipitation. We identified tubulin and heat shock 70 proteins as binding to intracellular C-terminal regions of the channel. To study functional effects, heag2 channels were expressed in Xenopus laevis oocytes for two-electrode voltage clamping. Coexpression of alpha-tubulin or the application of colchicine significantly prolonged channel activation times. Application at different times of colchicine gave similar results. The data suggest that colchicine application and tubulin expression do not affect heag2 trafficking and that tubulin may associate with the channel to cause functional effects. Coexpression of heat shock 70 proteins had no functional effect on the channel. The role of tubulin in the cell cytoskeleton suggests a link for the heag2 channel in tubulin-dependent physiological functions, such as cellular proliferation.