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Carbonization is one of the main methods for comprehensive utilization of bituminous coal. Bituminous coal and its solid products from carbonization, namely char and coke, have complex pore structures, which can be characterized by fractals. We performed a study on the fractal structure of the solid products prepared from the bituminous coal of Shuiyu mine in Shanxi Province, China, at different carbonization temperatures (25°C∼1000°C) by synchrotron radiation small-angle X-ray scattering (SAXS). The results show that the bituminous coal has a surface fractal structure during the whole carbonization process. The variation of fractal dimension with carbonization temperature illustrates the different stages of the carbonization process. [ABSTRACT FROM AUTHOR]

Abstract Climate change and human activities have substantially changed hydrological and geomorphologic processes, particularly in upper mountainous catchments. The Jinsha River Basin (JRB), the uppermost region of the Yangtze River and the largest hydropower production region in China, was chosen to investigate the sediment load responses to climate variations and human activities. The non-parametric Mann-Kendall test and double mass curve were used to explore the spatial-temporal variations of hydro-meteorological variables and quantify the contributions of climate variation and human activities to changes in discharge and sediment load in the JRB from the 1950s to 2015. The results indicate that human activities, in particular cascade damming, were the governing factor for sediment load changes, while climate variations (increasing precipitation and snow and glacier melt) dominated the discharge changes in the JRB. The average annual sediment load at the Panzhihua (PZH) station increased by 42.4% from 1966–1984 to 1985–2010, mainly due to mineral extraction and deforestation, followed by a decrease of 75.9% in 2011–2015 because of the operation of the cascade reservoirs in the middle JRB since 2010. The construction of new dams like the Xiangjiaba Reservoir (2012) and the Xiluodu Reservoir (2013) in the lower JRB and many other cascade reservoirs since 2010 in the middle JRB further decreased the sediment load by 58.5% (BHT) and 83.8% (XJB) in the recent five years from 2011 to 2015. Although channel erosion downstream of the XJB Dam can provide new sediment to the Three Gorges Reservoir (TGR), the sedimentation rate of the TGR has decreased rapidly and will continue to be reduced due to the construction of more dams in the future. Highlights • Sediment load reduced significantly in the Jinsha River after 2010. • Human activities particularly cascade reservoirs' operation dominated sediment load changes. • Discharge rise at the PZH was dominated by increasing precipitation and snow and glacier melt. • Sediment load decline in the Jinsha River reduced the sedimentation rate of the Three Gorges Reservoir. [ABSTRACT FROM AUTHOR]

Pleurospermum lindleyanum (Lipsky) B. Fedtsch is a perennial herb classified in the Apiaceae family, genus Pleurospermum, chiefly native to the Taxkorgan County, Xinjiang, China. In the Xinjiang Province, it is a well-known ethnic traditional herb, often addressed by its tribal name, Kurumuti. It grows in harsh conditions over 4000 m above sea level, such as the Pamirs plateau. It is rich in flavonoids, coumarins, terpenoids, essential oil, substances that have been widely applied in the prevention and treatment of hypertension, diabetes, coronary heart disease, and cerebral thrombosis by local Tajik residents. The present study aimed to evaluate the antihypertensive effects of the Pleurospermum Lindleyanum aqueous extract (PLAE) in spontaneously hypertensive rats (SHRs). The Pleurospermum lindleyanum was collected from the Taxkorgan Tajik Autonomous County, Xinjiang, China. The main chemical composition of PLAE was identified using the ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS). SHRs were treated by gavage with PLAE (equivalent to Pleurospermum lindleyanum 5 or 10 g/kg/day) for 6 weeks, using Captopril (10 mg/kg/day) as positive control. The systolic blood pressure (SBP), renal and cardiac morphology, plasma levels of angiotensin-converting enzyme (ACE), aldosterone (ALD), angiotensinⅡ (AngⅡ), superoxide dismutase (SOD), endothelin-1 (ET-1) and nitric oxide (NO) were measured. A total of 30 compounds were identified in PLAE. PLAE significantly attenuated the SBP of SHRs. The effects began after 3 weeks of administration and then became steady and long-lasting. Its potential mechanisms may be associated with the protective effects on renal and cardiac injury caused by hypertension, the decrease of plasma vasoconstrictors, such as ACE, ALD, AngⅡ, and ET-1 levels, the maintenance of NO/ET balance, the increase in plasma NO levels and SOD activity, thereby reducing oxidative stress. Pleurospermum lindleyanum can be suggested as a novel antihypertensive ethnic traditional herb, which lays the foundation for researching safe and effective antihypertensive herbal medicines. [Display omitted] • The incidence of primary hypertension increasing year by year, and becoming a major risk factor for many cardiovascular diseases. • The Pleurospermum Lindleyanum aqueous extract (PLAE) can reduce the systolic blood pressure, and protect cardiac and renal injury caused by hypertension. • The antihypertensive mechanisms could be the decrease of plasma ACE, ALD, AngⅡ levels, the increase of plasma NO, SOD levels. [ABSTRACT FROM AUTHOR]

• Damming dominated reduced sediment fluxes, followed by climate change. • The Wenchuan Earthquake had little effect on long-term downstream sediment flux. • The drastically decreased sediment fluxes benefit the Three Gorges Reservoir. Riverine sediment flux is a crucial proxy influencing channel morphology, biogeochemical processes, and riverine ecosystems. However, recent climate change and multiple anthropogenic activities have substantially altered the sediment regimes of the world's rivers. On a basis of the "multiple double mass curves" method, this study selected the Jialing River (JR) basin as a case study to distinguish the relative impacts of climate change, land-use change, and damming on changes in the runoff and sediment flux over the past 60 years. The results showed that the sediment fluxes in the JR basin drastically decreased by 57–77% from the baseline period (1950s–1984) to the post-change period (1985–2017) mainly due to damming (60–75%), climate change (5–30%), and revegetation (10–20%). The runoff in the JR basin also exhibited a reduction (12–22%) likely because of the joint impacts of a reduction in precipitation and the restoration of vegetation. Although the 2008 Wenchuan Earthquake (M = 7.9) increased the short-term sediment fluxes, its impact on the long-term sediment fluxes in the downstream areas of the JR basin was limited as a result of the buffering effect of the thousands of constructed reservoirs. The decreased sediment fluxes in the JR basin benefit the life expectancy of the Three Gorges Reservoir (the world's largest hydropower plant), but the reduced runoff can exacerbate water stress. The findings of our study have important implications for better management of water resources, sediment fluxes, and reservoir sedimentation not only for the JR basin, but also for the Three Gorges Reservoir. [ABSTRACT FROM AUTHOR]

Sleep problem among undergraduate students has become one of the most pressing public health problems. This study aimed to explore the latent class of sleep patterns and the factors affecting sleep in Chinese students of medical university. 3423 students participated in the cross-sectional study. The survey consisted of the reduced Morningness-Evening Questionnaire, the Pittsburgh Sleep Quality Index, and Health-Promoting Lifestyle Profile-II. Latent profile analysis and multinominal logistic regression analysis were performed. Three potential sleep categories were identified: "sleep disorder group" (1.87 %), "daytime dysfunction group" (24.42 %), and "good sleep group" (73.71 %). Compared with the "good sleep group," the "sleep disorder group" showed monthly living expenses (RMB) ≥ 3000 yuan (OR) = 13.04), interpersonal relationships as poor (OR = 3.71), health status as poor (OR = 45.09), circadian rhythm as eveningness (OR = 6.17), and poor health-promoting lifestyles (OR = 2.090) as its risk factors (all p < 0.05). Meanwhile, sophomore (OR = 1.75), junior (OR = 1.52), interpersonal relationships as poor (OR = 1.88), health status as poor (OR = 4.62), intermediate-chronotype (OR = 2.19), eveningness chronotype (OR = 5.66), and health-promoting lifestyles as poor (OR = 1.55) were identified as risk factors for the "daytime dysfunction group" (all p < 0.05). C ausal conclusions can not be drawn and recall bias in data collection. Significant population heterogeneity was found in the sleep quality. Implementing targeted interventions focusing on circadian rhythm and lifestyle is crucial to improve the sleep quality of students with different conditions. • Research on sleep quality in Chinese undergraduate of medical university was limited. • Our study was the first to explore their sleep quality patterns and influence factors. • Three categories (sleep disorder; daytime dysfunction; good sleep) were identified. • Sleep disorders and daytime dysfunction were each related with five different factors. [ABSTRACT FROM AUTHOR]

Carbonisation is one of the important methods to improve the utilisation of coal. The structural composition of coal plays an important role in coal carbonisation. This work used small-angle X-ray scattering (SAXS) to investigate the pore structure of three kinds of raw coals with different carbon content derived from Xingtai City, Hebei Province, China. The structures of the corresponding cokes obtained through carbonisation at 1200°C were investigated by elemental analysis and SAXS. In addition, the gasification reaction of the three cokes (C1, C2, C3) with CO2 were studied by thermogravimetric analysis. The SAXS results indicate that the surface fractal dimension increases while the pore size decreases, and the pore distribution became wider after carbonisation. In addition, all coals and cokes present a positive deviation from Porod's law, indicating that there is a micro-fluctuation of electron density in the samples. Besides, it exhibites a negative correlation has been found between the degree of deviation from Porod's law and the carbon content. The gasification reactivity of cokes C1 and C3 in CO2 are higher than that of C2, indicating that the pore structures affect the gas reactivity of the three different metamorphic degree cokes in CO2. [ABSTRACT FROM AUTHOR]

The construction of an engineered cover layer over landfills is a common method applied to reduce the emission of hazardous gases into the atmosphere. Landfill gas pressures can reach 50 kPa or even higher in some cases, thus posing a serious threat to nearby properties and human safety. As such, the evaluation of gas breakthrough pressure and gas permeability in a landfill cover layer is of great necessity. In this study, the loess soil that is often applied as a cover layer in landfills in northwestern China was used to conduct gas breakthrough, gas permeability, and mercury intrusion porosimetry (MIP) tests. Resultantly, the smaller the capillary tube diameter, the higher the capillary force, and the more significant the capillary effect. Gas breakthrough could be attained with no difficulty, provided that the capillary effect was minimal or approached zero. A good fit between the experimental gas breakthrough pressure–intrinsic permeability relationship and a logarithmic equation was found. The mechanical effect blew up the gas flow channel. In the worst-case scenario, the mechanical effect could lead to the overall failure of a loess cover layer in a landfill. A new gas flow channel was formed between the rubber membrane and the loess specimen as a result of the interfacial effect. Although both the mechanical and interfacial effects can elevate the gas emission rate, the latter did not play a role in the improvement of the gas permeability; therefore, misleading interference took place in the evaluation of the gas permeability, and an overall failure of the loess cover layer. To tackle this problem, the point at which the large- and small-effective stress asymptotes cross on the volumetric deformation– P eff diagram may be applied to give early warning signals of the potential overall failure of the loess cover layer in landfills in northwestern China. • The capillary effect is a crucial factor affecting the gas breakthrough pressure. • Both the mechanical and interfacial effects gear up the gas emission rate. • The interfacial effect can mislead the assessment of the failure of a cover layer. • The volumetric deformation goes up with decrease in P eff in an exponential manner. • Such exponential relationship gives early warning of the failure of a cover layer. [ABSTRACT FROM AUTHOR]

The Guangxi Partridge chicken is a well-known chicken breed in southern China with good meat quality, which has been bred as a meat breed to satisfy the increased demand of consumers. Compared with line D whose body weight is maintained at the average of the unselected group, the growth rate and weight of the selected chicken group (line S) increased significantly after breeding for four generations. Herein, transcriptome analysis was performed to identify pivotal genes and signal pathways of selective breeding that contributed to potential mechanisms of growth and development under artificial selection pressure. The average body weight of line S chickens was 1.724 kg at 90 d of age, which showed a significant increase at 90 d of age than line D chickens (1.509 kg), although only the internal organ ratios of lung and kidney changed after standardizing by body weight. The myofiber area and myofiber density of thigh muscles were affected by selection to a greater extent than that of breast muscle. We identified 51, 210, 31, 388, and 100 differentially expressed genes (DEGs) in the hypothalamus, pituitary, breast muscle, thigh muscle, and liver between the two lines, respectively. Several key genes were identified in the hypothalamus-pituitary-muscle axis, such as FST, THSB, PTPRJ, CD36, PITX1, PITX2, AMPD1, PRKAB1, PRKAB2, and related genes for muscle development, which were attached to the cytokine–cytokine receptor interaction signaling pathway, the PPAR signaling pathway, and lipid metabolism. However, signaling molecular pathways and the cell community showed that elevated activity in the liver of line S fowl was mainly involved in focal adhesion, ECM-receptor interaction, cell adhesion molecules, and signal transduction. Collectively, muscle development, lipid metabolism, and several signaling pathways played crucial roles in the improving growth performance of Guangxi Partridge chickens under artificial selection for growth rate. These results support further study of the adaptation of birds under selective pressure. [ABSTRACT FROM AUTHOR]