Achievements and Challenges in Improving Air Quality in China: Analysis of the Long-Term Trends from 2014 to 2022

Due to the implementation of air pollution control measures in China, air quality has significantly improved, although there are still additional issues to be addressed. This study used the long-term trends of air pollutants to discuss the achievements and challenges in further improving air quality in China. The Kolmogorov-Zurbenko (KZ) filter and multiple-linear regression (MLR) were used to quantify the meteorology-related and emission-related trends of air pollutants from 2014 to 2022 in China. The KZ filter analysis showed that PM2.5 decreased by 7.36 ± 2.92% yr􀀀 1, while daily maximum 8-h ozone (MDA8 O3) showed an increasing trend with 3.71 ± 2.89% yr􀀀 1 in China. The decrease in PM2.5 and increase in MDA8 O3 were primarily attributed to changes in emission, with the relative contribution of 85.8% and 86.0%, respectively. Meteorology variations, including increased ambient temperature, boundary layer height, and reduced relative humidity, also contributed to the reduction of PM2.5 and the enhancement of MDA8 O3. The emission-related trends of PM2.5 and MDA8 O3 exhibited continuous decrease and increase, respectively, from 2014 to 2022, while the variation rates slowed during 2018–2020 compared to that during 2014–2017, highlighting the challenges in further improving air quality, particularly in simultaneously reducing PM2.5 and O3. This study recommends reducing NH3 emissions from the agriculture sector in rural areas and transport emissions in urban areas to further decrease PM2.5 levels. Addressing O3 pollution requires the reduction of O3 precursor gases based on site-specific atmospheric chemistry considerations

Long‐circulating drug‐dye‐based micelles with ultrahigh pH‐sensitivity for deep tumor penetration and superior chemo‐photothermal therapy

Nanocarriers for chemo‐photothermal therapy suffer from insufficient retention at the tumor site and poor penetration into tumor parenchyma. A smart drug‐dye‐based micelle is designed by making the best of the structural features of small‐molecule drugs. P‐DOX is synthesized by conjugating doxorubicin (DOX) with poly(4‐formylphenyl methacrylate‐co‐2‐(diethylamino) ethyl methacrylate)‐b‐polyoligoethyleneglycol methacrylate (P(FPMA‐co‐DEA)‐b‐POEGMA) via imine linkage. Through the π–π stacking interaction, IR780, a near‐infrared fluorescence dye as well as a photothermal agent, is integrated into the micelles (IR780‐PDMs) with the P‐DOX. The IR780‐PDMs show remarkably long blood circulation (t1/2β = 22.6 h). As a result, a progressive tumor accumulation and retention are presented, which is significant to the sequential drug release. Moreover, when entering into a moderate acidic tumor microenvironment, IR780‐PDMs can dissociate into small‐size conjugates and IR780, which obviously increases the penetration depth of drugs, and then improves the lethality to deep‐seated tumor cells. Owing to the high delivery efficiency and superior chemo‐photothermal therapeutic efficacy of IR780‐PDMs, 97.6% tumor growth in the A549 tumor‐bearing mice is suppressed with a low dose of intravenous injection (DOX, 1.5 mg kg−1; IR780, 0.8 mg kg−1). This work presents a brand‐new strategy for long‐acting intensive cancer therapy.The authors acknowledge the financial support of the National Key Basic Research Program (no. 2017FYA0205301 and no. 2010CB933901), the Natural Science Foundation of China (no. 81921002 and no. 81327002), and the China Postdoctoral Science Foundation (no. 2018M642026).Peer reviewe

Novel Automatic Idle Speed Control System with Hydraulic Accumulator and Control Strategy for Construction Machinery

To reduce the energy consumption and emissions of the hydraulic excavator, a two-level idle speed control system with a hydraulic accumulator for the construction machinery is proposed to reduce the energy consumption and improve the control performance of the actuator when the idle mode is cancelled. The structure and working principle are analyzed. The hydraulic accumulator (HA) is used to store the energy, which can provide backup pressured fluid when the idle mode is cancelled. Then, a method of how to set the pressure differential between the hydraulic accumulator and the load is proposed and the control law is discussed. The test rig is built. The experimental result shows that the idle speed can be switched among the first idle speed, the second idle speed and the normal speed automatically. Though the idle speed in the novel system can be reduced more than that in the conventional automatic idle speed control system (AISCS), the proposed system can still build the actuator pressure more quickly when the idle mode is cancelled. When compared to the system without the idle speed control, the energy saving of the proposed system is about 67%. The proposed two-level idle speed control system with a HA can achieve a high energy efficiency and a good control performance

High Uric Acid Induces Insulin Resistance in Cardiomyocytes In Vitro and In Vivo.

Clinical studies have shown hyperuricemia strongly associated with insulin resistance as well as cardiovascular disease. Direct evidence of how high uric acid (HUA) affects insulin resistance in cardiomyocytes, but the pathological mechanism of HUA associated with cardiovascular disease remains to be clarified. We aimed to examine the effect of HUA on insulin sensitivity in cardiomyocytes and on insulin resistance in hyperuricemic mouse model. We exposed primary cardiomyocytes and a rat cardiomyocyte cell line, H9c2 cardiomyocytes, to HUA, then quantified glucose uptake with a fluorescent glucose analog, 2-NBDG, after insulin challenge and detected reactive oxygen species (ROS) production. Western blot analysis was used to examine the levels of insulin receptor (IR), phosphorylated insulin receptor substrate 1 (IRS1, Ser307) and phospho-Akt (Ser473). We monitored the impact of HUA on insulin resistance, insulin signaling and IR, phospho-IRS1 (Ser307) and phospho-Akt levels in myocardial tissue of an acute hyperuricemia mouse model established by potassium oxonate treatment. HUA inhibited insulin-induced glucose uptake in H9c2 and primary cardiomyocytes. It increased ROS production; pretreatment with N-acetyl-L-cysteine (NAC), a ROS scavenger, reversed HUA-inhibited glucose uptake induced by insulin. HUA exposure directly increased the phospho-IRS1 (Ser307) response to insulin and inhibited that of phospho-Akt in H9C2 cardiomyocytes, which was blocked by NAC. Furthermore, the acute hyperuricemic mice model showed impaired glucose tolerance and insulin tolerance accompanied by increased phospho-IRS1 (Ser307) and inhibited phospho-Akt response to insulin in myocardial tissues. HUA inhibited insulin signaling and induced insulin resistance in cardiomyocytes in vitro and in vivo, which is a novel potential mechanism of hyperuricemic-related cardiovascular disease

Wide-Angle Frequency Scanning Leaky Wave Antenna Loaded CSRR Patch Based on SSPP Transmission Line

A novel composite left-and-right-composite-handed leaky wave antenna is proposed based on Spoof Surface Plasmon Polaritons slow-wave transmission line at microwave band in this paper. Wide-angle frequency scanning of the antenna is achieved by combining the slow-wave dispersion characteristics of Spoof Surface Plasmon Polaritons and the left-and-right-composite-handed characteristics of the complementary split ring resonator structure. The simulated and experimental results show that, with the increase of frequency, the radiation mode of the antenna gradually changed from slow-wave mode to fast-wave radiation mode, and the pattern changed continuously. The scanning region of the main beams proposed covers 110° in φ=0° plane when the frequency increases from 8GHz to 15GHz, and the gain of the antenna kept between 7dBi and 10.4dBi