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Purpose: To investigate the hypoglycemic and hepatoprotective effects of Angelica dahurica polysaccharide (ADP). Methods: The contents of neutral sugar, total glyoxylate and total protein, molecular mass and monosaccharide composition of ADP were determined by the phenol-sulfuric acid method, the sulfuric acid-carbazole method, the Coomassie brilliant blue method, high performance gel permeation chromatography (HPGPC) and high performance liquid chromatography (HPLC), respectively. Type 2 diabetes mellitus (T2DM) was induced in rats by high-fat and high-sucrose diet feeding combined with injection of streptozotocin (STZ). Five groups of rats were set up: blank control, model, low-dose ADP (200 mg/kg mb), high-dose ADP (400 mg/kg mb), and positive control (200 mg/kg mb metformin). The rats in the blank control and model groups were gavaged with distilled water. After four weeks of administration, body mass, fasting blood sugar (FBG), oral glucose tolerance test (OGTT), fasting insulin (FINS), homeostatic model assessment for insulin resistance (HOMA-IR) and glycogen levels were measured, hematoxylin-eosin (HE) staining was used to observe hepatic histopathological changes, and commercial kits were used to determine lipid metabolism, oxidative stress and liver function indexes. Results: ADP had the following composition: (83.26 ± 0.67)% neutral sugar, (8.32 ± 1.25)% glyoxylate, and (0.64 ± 0.07)% protein, and its molecular mass was 10.28 × 103 Da. Monosaccharide composition analysis showed that ADP consisted of rhamnose, arabinose, galactose, glucose, mannose, glucuronide acid and galacturonic acid with a molar ratio of 0.09:0.45:0.43:1.00:0.05:0.53:0.08. ADP significantly increased body mass, blood glucose, FINS and glycogen levels of T2DM rats (P < 0.01), significantly decreased FBG and HOMA-IR (P < 0.01), improved liver histopathology, and significantly improved lipid metabolism, oxidative stress and liver function indexes (P < 0.01). Conclusion: ADP has hypoglycemic and hepatoprotective effects, probably through regulating abnormal lipid metabolism and oxidative stress.

Roofs with high-reflectance (solar reflectance) coating, commonly known as cool roofs, can stay cool in the sun, thereby reducing building energy consumption and mitigating the urban heat island. However, chemical-physical degradation and biological growth can decrease their solar reflectance and the ability to save energy. In this study, the solar spectral reflectance of 12 different roofing products with an initial albedo of 0.56–0.90 was measured before exposure and once every three months over 32 months. Specimens were exposed on the roofs of dormitory buildings in Xiamen and Chengdu, each major urban areas with hot summers. The albedos of high and medium-lightness coatings stabilized in the ranges 0.45–0.62 and 0.36–0.59 in both cities, respectively. This study yielded albedo loss exceeded those reported in the latest Chinese standard by 0.08–0.15. Finally, DesignBuilder (EnergyPlus) simulations estimate that a new cool roof with albedo 0.78 on a six-story dormitory building will yield annual site energy savings (heating and cooling) for the top floor, which are 8.01 kWh/m2 (24.2%) and 9.12 kWh/m2 (26.3%) per unit floor area in Xiamen and Chengdu, respectively; while an aged cool roof with albedo 0.45 and 0.56 will yield the annual savings by 5.12 kWh/m2 (15.4%) and 2.47 kWh/m2 (10.5%) in these two cities.

The major link between satellite-derived vertical column densities (VCDs) of nitrogen dioxide (NO 2) and ground-level concentrations is theoretically the NO 2 mixing height (NMH). Various meteorological parameters have been used as a proxy for NMH in existing studies. This study developed a nested XGBoost machine learning model to convert VCDs of NO 2 into ground-level NO 2 concentrations across China using Geostationary Environmental Monitoring Spectrometer (GEMS) measurements. This nested model was designed to directly incorporate NMH into the methodological framework to estimate satellite-derived ground-level NO 2 concentrations. The inner machine learning model predicted the NMH from meteorological parameters, which were then input into the main XGBoost machine learning model to predict the ground-level NO 2 concentrations from its VCDs. The inclusion of NMH significantly enhanced the accuracy of ground-level NO 2 concentration estimates; i.e., the R2 values were improved from 0.73 to 0.93 in 10-fold cross-validation and from 0.88 to 0.99 in the fully trained model. Furthermore, NMH was identified as the second most important predictor variable, following the VCDs of NO 2. Subsequently, the satellite-derived ground-level NO 2 data were analyzed across subregions with varying geographic locations and urbanization levels. Highly populated areas typically experienced peak NO 2 concentrations during the early morning rush hour, whereas areas categorized as lightly populated observed a slight increase in NO 2 levels 1 or 2 h later, likely due to regional pollutant dispersion from urban sources. This study underscores the importance of incorporating NMH in estimating ground-level NO 2 from satellite column measurements and highlights the significant advantages of geostationary satellites in providing detailed air pollution information at an hourly resolution. [ABSTRACT FROM AUTHOR]

This study presents the experimental measurement of the energy consumption of three top-floor air-conditioned rooms in a typical office building in Chongqing, which is a mountainous city in the hot-summer and cold-winter zone of China, to examine the energy performance of white and sedum-tray garden roofs. The energy consumption of the three rooms was measured from September 2014 to September 2015 by monitoring the energy performance (temperature distributions of the roofs, evaporation, heat fluxes, and energy consumption) and indoor air temperature. The rooms had the same construction and appliances, except that one roof top was black, one was white, and one had a sedum-tray garden roof. This study references the International Performance Measurement and Verification Protocol (IPMVP) to calculate and compare the energy savings of the three kinds of roofs. The results indicate that the energy savings ratios of the rooms with the sedum-tray garden roof and with the white roof were 25.0% and 20.5%, respectively, as compared with the black-roofed room, in the summer; by contrast, the energy savings ratios were −9.9% and −2.7%, respectively, in the winter. Furthermore, Annual conditioning energy savings of white roof (3.9 kWh/m2) were 1.6 times the energy savings for the sedum-tray garden roof. It is evident that white roof is a preferable choice for office buildings in Chongqing. Additionally, The white roof had a reflectance of 0.58 after natural aging owing to the serious air pollution worsened its thermal performance, and the energy savings reduced by 0.033 kWh/m2·d. Evaporation was also identified to have a significant effect on the energy savings of the sedum-tray garden roof.

Self-assembled monolayers (SAMs) have been successfully employed to enhance the efficiency of inverted perovskite solar cells (PSCs) and perovskite/silicon tandem solar cells due to their facile low-temperature processing and superior device performance. Nevertheless, depositing uniform and dense SAMs with high surface coverage on metal oxide substrates remains a critical challenge. In this work, we propose a holistic strategy to construct composite hole transport layers (HTLs) by co-adsorbing mixed SAMs (MeO-2PACz and 2PACz) onto the surface of the H2O2-modified NiOx layer. The results demonstrate that the conductivity of the NiOx bulk phase is enhanced due to the H2O2 modification, thereby facilitating carrier transport. Furthermore, the hydroxyl-rich NiOx surface promotes uniform and dense adsorption of mixed SAM molecules while enhancing their anchoring stability. In addition, the energy level alignment at the interface is improved due to the utilization of mixed SAMs in an optimized ratio. Furthermore, the perovskite film crystal growth is facilitated by the uniform and dense composite HTLs. As a result, the power conversion efficiency of PSCs based on composite HTLs is boosted from 22.26% to 23.16%, along with enhanced operational stability. This work highlights the importance of designing and constructing NiOx/SAM composite HTLs as an effective strategy for enhancing both the performance and stability of inverted PSCs. [ABSTRACT FROM AUTHOR]