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Eutrophication of lacustrine environments with frequent cyanobacterial blooms has become a serious problem. Overpopulation and runoff into groundwater and lakes from fertilizers with too much nitrogen and phosphorous have caused most of the problems. Here, we first devised a land use and cover classification system based on the local characteristics of the first-level protected area of Lake Chaohu (FPALC). Lake Chaohu is the fifth largest freshwater lake in China. The land use and cover change (LUCC) products were produced using sub-meter resolution satellite data from 2019 to 2021 in the FPALC. This study presents an evaluation of the effectiveness of the established protected areas. The results show the most impactful type was the reduction in cropland with an area that declined from 7446.4 hm2 to 6433.3 hm2 from 2019 to 2021. Most of the reduced cropland was converted into wetlands, with 460.2 hm2 and 152.0 hm2 of cropland restored to wetlands from 2019 to 2020 and 2020–2021, respectively. The area of cyanobacterial blooms in Lake Chaohu showed a downward trend, and the lacustrine environment was greatly improved after the establishment of the FPALC. These quantified data can inform decision-making related to Lake Chaohu conservation and provide a reference for managing the aquatic environment in other watersheds. [Display omitted] • Watershed LUCC was mapped using very high-resolution satellite data (∼0.5 m). • A new LUCC classification system is designed for protected area. • LUCC trends and underlying drivers in the protected area were quantified. • The effect of protected area on lacustrine environments was evaluated. • The establishment of FPALC improved the lacustrine environment. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) have been developed with numerous beneficial applications. However, rodent models demonstrate that exposure to MWCNTs via respiratory pathways results in pulmonary fibrosis. Therefore, they could elicit a potential risk of pulmonary fibrosis in humans due to occupational or consumer exposure. Sirtuin 6 (SIRT6), a nicotinamide adenine dinucleotide (NAD)-dependent deacetylase, has been proved to prevent fibrosis in the liver, renal and myocardial tissues. In this present study, we aimed to explore the role of SIRT6 in MWCNTs-induced epithelial-mesenchymal transition (EMT), one of the major contributor of lung fibrogenesis in human bronchial epithelial BEAS-2B cells. We found that the protein level of SIRT6 was elevated after exposure to MWCNTs in BEAS-2B cells. Overexpression of SIRT6 significantly inhibited MWCNTs-induced EMT and EMT-like cell behaviors in BEAS-2B cells. Moreover, wild-type SIRT6 was found to decrease MWCNTs-induced phosphorylation of Smad2, but not mutant SIRT6 (H133Y) without histone deacetylase activity. In conclusion, our study demonstrated that SIRT6 inhibited MWCNTs-induced EMT in BEAS-2B cells through TGF-β1/Smad2 signaling pathway, which depended on its deacetylase activity, and provided evidences that targeting SIRT6 could be a potential novel therapeutic strategy for MWCNTs-induced pulmonary fibrosis. • Sirtuin 6 (SIRT6) was elevated after exposure to MWCNTs in BEAS-2B cells. • SIRT6 overexpression inhibited MWCNTs-induced epithelial-mesenchymal transition (EMT). • SIRT6 inhibited EMT via TGF-β1/Smad2 pathway, depending on its deacetylase activity. • SIRT6 is a promising target to protect against MWCNTs-induced pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

The key odorants of Jiugui -series Baijiu (Y and R) were explored systematically for the first time by a sensory-directed flavor analysis approach. A total of 144 aroma-active compounds were identified by pH regulated liquid-liquid extraction (LLE) and headspace solid phase microextaction (HS-SPME) combined with gas chromatography-olfactometry-mass spectrometry (GC-O-MS), and 92 of these were first reported. The aroma extract dilution analysis (AEDA) was used for screening the potential important aroma compounds. The overall aroma profiles of Y and R were successfully simulated (similarity = 95.47%, and 90.21%, respectively) by mixing the odorants (OAV ≥ 1) with their natural concentrations in 52% ethanol/water solutions. The omission tests revealed that ethyl acetate, ethyl lactate, ethyl butyrate, ethyl pentanoate, ethyl hexanoate, ethyl octanoate, ethyl dodecanoate, dimethyl trisulfide, acetic acid, propionic acid, butanoic acid, isovaleric acid, hexanoic acid, octanoic acid, and p -cresol were identified as the key aroma compounds. In particular, benzenemethanethiol played an important role in the typical aroma of Y and R, which had a burnt or baked-like odor and was a new finding. • The key odorants of Fuyu-flavor-type Baijiu (FFTB) were explored for the first time. • 92 compounds were newly identified as aroma-active odorants in FFTB. • Benzenemethanethiol played an important role in the typical aroma of FFTB. • 10 important compounds' odor thresholds in ethanol/water solution were evaluated. [ABSTRACT FROM AUTHOR]

There has been a great concern about the neurotoxicity of fluoride since it can pass through the blood-brain barrier and accumulate in the brain. It has been suggested that apoptosis plays a vital role in neurotoxicity of fluoride. However, whether p53-mediated apoptotic pathway is involved is still unclear. Our results showed that apoptosis was induced after treatment with 40 and 60 mg/L of NaF for 24 h in human neuroblastoma SH-SY5Y cells. Exposure to 60 mg/L of NaF for 24 h significantly upregulated the levels of p53 and apoptosis-related proteins including PUMA, cytochrome c (cyto c ), cleaved caspase-3 and cleaved PARP, whereas downregulated Bcl-2 in SH-SY5Y cells. Meanwhile, fluoride increased p53 nuclear translocation, cyto c release from mitochondria to cytoplasm and mitochondrial translocation of Bax in SH-SY5Y cells. Fluoride-induced increases of apoptotic rates and apoptosis-related protein levels were significantly attenuated by inhibiting p53 transcriptional activity with pifithrin-α. In addition, fluoride inhibited the deacetylase activity of SIRT1 and increased p53 (acetyl K382) level in SH-SY5Y cells. Apoptosis and upregulation of cleaved caspase-3, cleaved PARP and p53 (acetyl K382) induced by fluoride could be ameliorated by SIRT1 overexpression or its activator resveratrol in SH-SY5Y cells. Taken together, our study demonstrates that fluoride induces apoptosis by inhibiting the deacetylase activity of SIRT1 to activate mitochondrial p53 pathway in SH-SY5Y cells, which depends on p53 transcriptional activity. Thus, SIRT1 may be a promising target to protect against neurotoxicity induced by fluoride. [ABSTRACT FROM AUTHOR]

Due to its important geographic location and unique environment, the Gansu and Qinghai region in China has been witnessing the emergence and development of Chinese civilization. This previously neglected region has recently been attracting people's attention. Existing studies have been mainly aiming to relate the spatiotemporal distributions of settlements to environmental changes. However, they generally fail to consider the evolution of social organizations and its role in impacting the spatiotemporal variations of prehistoric settlements. In this paper, we analyzed the spatiotemporal distribution and rank-size of prehistoric settlements in the Gansu-Qinghai region based on GIS analytical methods and reconstructed the process of cultural inheritance and social evolution. The examined chronological periods were demonstrated to be concomitant with different settlement development patterns, and most settlements in an older period were abandoned in the subsequently younger period, indicating poor inheritance. The occurrence of a three-tier regional settlement system during the late Yangshao–Majiayao period indicates fundamental changes in social organization, which is possibly related to the rise of a chiefdom-level society. Such a regional social stratification was intensified during the Qijia period, when a four-tier settlement system emerged. However, the complexity of the settlement system got weakened during the Bronze Age, as is indicated by the lowered hierarchy of the settlement system. The drying and cooling climatic event rendered nomadism the prevalent subsistence among the humans in the Gansu and Qinghai region who used to survive by participating in agricultural activities. • Use Gis to analyse the settlement morophology. • Use the rank-size to analyse the settlement system. • Development of trajectories settlement system. [ABSTRACT FROM AUTHOR]

The purpose of this study is to examine the association between hourly air pollution on hourly physical activity (PA) and sedentary behavior (SB) among college students in Beijing, China. The secondary aim was to examine such associations varied at specific time. A total of 340 participants were recruited from the Tsinghua University, in Beijing, China. Accelerometers provided PA measures, including moderate-to-vigorous physical activity (MVPA), walking steps, energy expenditure and sedentary time for 7 consecutive days. Corresponding air pollution data by the Beijing Municipal Ecological Environment Bureau in the closed site (Wan Liu site) in Tsinghua University were collected including average hourly air quality index (AQI) and PM 2.5 (μg/m³). Associations were estimated using linear individual fixed-effect regressions. We also conducted an air pollution risk perception survey among 2307 freshmen (76.6% males) who were enrolled in Tsinghua in 2016, and the survey was done in May 22–26, 2017. A one level increase in hourly air quality index (AQI) was associated with a reduction in 1-h PA by 0.083 (95% confidence interval [CI] = -0.137, −0.029) minutes of MVPA, 8.8 (95% CI = −15.0, −2.6) walking steps, 0.65 (95% CI = -1.03, −0.27) kcals of energy expenditure. A 10 μg/m³ increase in air pollution concentration in hourly PM 2.5 was associated with a reduction in 1-h PA by 0.021 (95% confidence interval [CI] = -0.033, −0.010) minutes of MVPA, 2.2 (95% CI = −3.5, −0.9) walking steps, 0.170 (95% CI = -0.250, −0.089) kcals of energy expenditure an increase in 1-h sedentary behavior 0.045 (0.005, 0.0845). At specific time, stronger negative associations of AQI and PM 2.5 air pollution with PA at 8 a.m., 4 p.m., 5 p.m. and 7 p.m. Similarly, stronger positive associations of 1 h AQI and PM 2.5 air pollution with SB at 8 a.m., 9 a.m., 11 a.m., and 7 p.m. A total of 94.9% participants (n = 2235) responded "yes" to air pollution change activities in the survey, which may partially explain PA change. Air pollution may discourage physical activity and increases sedentary behavior among freshman students living in Beijing, China. This is preliminary study. The impact of air pollution on physical activity and sedentary behavior at a specific time may be different. There are large variations in walking steps in specific time. Trend for walking steps in specific time in one day among the freshman. Image 1 • Air pollution may discourage physical activity behavior. • Air pollution may increase sedentary behavior. • The impact of air pollution on health behavior may be different at a specific time. [ABSTRACT FROM AUTHOR]