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The characteristics of soil holding capacity for different shrub-grass patterns are important to research the mechanisms regulating vegetation on slopes. The objective of this study was to describe the characteristics and mechanisms of soil erosion and hydraulic parameters under different vegetation patterns in the Pisha sandstone area of Inner Mongolia on lands of 8° slope gradient. We carried out field scouring experiments on five different shrub-grass patterns as treatments, viz no shrubs (GL), shrubs on the upper part of the slope (SU), middle part of the slope (SM) and lower part of the slope (SL). We designated bare slope (BL) as the control. We employed three different water flow rates (15, 20, 30 L·min−1). Our results showed that the contribution of plant root systems to slope sediment reduction ranged from 64 to 84%. The root systems proved to be the main contributing factor to reduction of erosion by vegetation. The relationship between soil detachment rate, stream flow power, and flow unit stream power under different scouring discharge rates showed that soil detachment declined in rank order as: BL > GL > SU > SM > SL. The SL pattern had the lowest soil detachment rate (0.098 g·m−2·s−1), flow stream power (2.371 W·m−2), flow unit stream power (0.165 m·s−1) and flow shear stress (16.986 Pa), and proved to be the best erosion combating pattern. The results of decision coefficient and path analysis showed that stream power was the most important hydraulic parameter for describing soil detachment rate. The combination of stream power and shear stress, namely Dr = 0.1ω − 0.03τ − 0.56 (R2 = 0.924), most accurately simulated the soil detachment characteristics on slopes. Our study suggests that the risk of soil erosion can be reduced by planting shrub-grass mixes on these slopes. Under the conditions of limited water resources and economy, the benefit of sediment reduction can be maximized by planting shrubbery on the lower parts of slopes.

Breakthroughs have been made for the natural gas exploration of the Middle Devonian and the Middle Permian formations in the Sichuan Basin in recent years. Nevertheless, its natural gas source is still not clear, which then affects the next exploration deployment decision. A comprehensive study is conducted on the geochemical characteristics of the Middle Devonian and the Middle Permian natural gas, the biomarkers of reservoir bitumen, and the source rocks. The results show that these natural gases are secondary cracking dry gas that includes more than 86% of methane content, a small amount of ethane, propane, and a non-hydrocarbon gas (e.g., nitrogen, carbon dioxide, and hydrogen sulfide). The natural gas maturity varies slightly in different regions. The carbon and hydrogen isotope values of natural gas are as follows: δ13C1 ranges from −35.7‰ to −27.3‰, δ13C2 ranges from −38.7‰ to −26.6‰, δ13C3 ranges from −37‰ to −26.5‰, δ2HCH4 ranges from −141‰ to −138‰, and δ2HC2H6 ranges from −164‰ to −112‰. The isotope values indicate that the genetic type of natural gas is the sapropelic type and the mixture type is dominated by sapropelic type. The difference between natural gas values of δ13C1, δ13C2, and δ2HCH4 in different regions is related to the contribution ratio of source rocks from different ages. The gases of the Middle Devonian and the Middle Permian of the Shuangyushi structure in Northwestern Sichuan, the Middle Permian of Southwestern Sichuan, and the Middle Permian of Paleo-uplift in Central Sichuan are mainly derived from the Cambrian Qiongzhusi Formation and the Middle-Lower Permian source rocks. The Middle-Upper Permian natural gases of the volcanic reservoir in Southwestern Sichuan is mainly from the Qiongzhusi source rock. The Middle Permian natural gases of the Hewanchang structure in Northwestern Sichuan, Eastern Sichuan, and Southern Sichuan are mainly derived from the Silurian Longmaxi source rock. The research results have important guiding significance for developing exploration and deployment solutions for natural gas of the Middle Devonian and the Middle Permian formation in the Sichuan Basin.

The purpose of this research was to investigate whether copper (Cu) exposure could induce apoptosis via endoplasmic reticulum stress (ERS) in skeletal muscle of broilers. A total of 240 one-day-old chickens were randomly divided into four groups by free access; the diets are as follows: control diet (Cu 11 mg/kg, control group) and high level of Cu diets (Cu 110 mg/kg, group I; Cu 220 mg/kg, group II; Cu 330 mg/kg, group III). The skeletal muscle tissues were collected on day 49 for further examination. The content of Cu, histopathology, and the expression levels of the genes and proteins related to ERS and apoptosis were detected. Results showed that the Cu levels in skeletal muscle were increased in a dose-dependent manner. Meanwhile, the spaces between the muscle fibers were wider with the increase of Cu content, and the myolysis was observed in group III. Besides, the mRNA expression levels of GRP78, GRP94, eIF2α, ATF6, XBP1, CHOP, Caspase-12, and Caspase3 were markedly increased in treated groups compared with control group, and the protein expression levels of GRP78, Caspase3, Active-Caspase3 and JNK were significantly elevated with the increase of dietary Cu. In summary, these findings suggested that Cu could induce apoptosis through ERS in skeletal muscle of broilers.

Copper (Cu), one of the heavy metals, is far beyond the carrying capacity of the environment with Cu mining, industrial wastewater discharging and the use of Cu-containing pesticides. Intaking excess Cu can cause toxic effects on liver, kidney, heart, but few studies report Cu toxicity on brain tissue. It is noteworthy that most toxicity tests are based on rodent models, but large mammals chosen as animal models has no reported. To explore the relationship of the Cu toxicity and mitochondria-mediated apoptosis on hypothalamus in pigs, the content of Cu, histomorphology, mitochondrial related indicators, apoptosis, and AMPK-mTOR signaling pathway were detected. Results showed that Cu could accumulate in hypothalamus and lead to mitochondrial dysfunction, evidenced by the decrease of ATP production, activities of respiratory chain complex I-IV, and mitochondrial respiratory function in Cu-treated groups. Additionally, the genes and proteins expression of Bax, Caspase-3, Cytc in treatment group were higher than control group. Furthermore, the protein level of p-AMPK was enhanced significantly and p-mTOR was declined, which manifested that AMPK-mTOR signaling pathway was activated in Cu-treated groups. In conclusion, this study illuminated that the accumulation of Cu could cause mitochondrial dysfunction, induce mitochondria-mediated apoptosis and activate AMPK-mTOR pathway in hypothalamus.

Sand-barrier setup is an important measure to protect the topsoil against wind erosion. Salix psammophila checkerboard barriers are used widely in the Mu Us Sandy Land in order to ensure the safety of life and agricultural production. To measure variations in soil structure and quality caused by barriers with different duration (7 years and 2 years), the composition of aeolian sandy soil particles and the soil organic carbon (SOC) distributions are studied; the dunes with no barrier are used as controls (CK). Analyzed by multi-fractal parameters, the topsoil samples are collected in the field and tested in the laboratory. The predominant soil particles are fine sand, medium coarse sand and clay, and the contents of silt and very fine sand increase with extending barrier duration, which shows a wider distribution range, greater dispersion degree and larger soil particle heterogeneity. The aeolian sandy particles, particularly fine granular grains, are deposited and accumulate at the bottom and top of dunes because of the barrier blocking effect. The particle size distribution (PSD) heterogeneity is the highest in 7-year barrier dunes and the lowest in the no barrier dunes. The mean values of D0 (Capacity dimension) of 7-year barrier dunes, D1 (entropy dimension) of the no barrier dunes and D1/D0 of 2-year barrier dunes are maxima. In addition, the PSD range and distribution increased with prolonged dune barrier duration, as well as the changes of Δf(∂) (shape of the multi-fractal spectrum) and Δ∂ (width of multi-fractal spectrum). SOC content increased with increasing barrier duration and decreasing D1/D0. The average SOC contents of 7-year barrier dunes were the maximum and one of no barrier dunes had the minimum SOC content, and their difference was significant (P Correlations between the SOC content and the PSD multi-fractal parameters of both 7-year and 2-year barrier dunes are significantly different (P

Due to Van der Waals or electrostatic interactions of surfactants active to all kinds of minerals, in low-rank coal (LRC) flotation, surfactants could both adsorb on the organic and mineral matter of LRC, thus increasing the hydrophobicity of them and resulting in the increase of clean coal yield as well as the ash content. In this work, density functional theory (DFT) calculations were clarified the adsorption mechanism of surfactant (C12EO, lauryl polyoxyethylene ether) on the LRC model molecules and kaolinite surfaces (the representative of organic and mineral matter in LRC). The DFT results demonstrate that the interaction strength between C12EO and LRC model molecules is stronger than that of kaolinite. Based on the calculation results, ultrasonic treatment was selected to expand the wettability difference between organic and mineral matter that adsorbed C12EO. The microcalorimetry results show that the wetting heat of organic matter that is adsorbed C12EO is unchanged basically after 30 s ultrasonic treatment. However, there is an obvious increase trend for the wetting heat of kaolinite. Flotation experiments of artificial mixed samples proved that ultrasonic treatment is useful in decreasing the extent of ash content in LRC flotation, thus improving the quality of clean coal in LRC flotation.

Aeolian sand transport into rivers is a crucial factor influencing channel sediment dynamics and fluvial processes in rivers that flow through desert areas. Few studies have examined the dynamic processes, controlling factors, and the amount of aeolian sand transported into river channels. Here, we report a case study of aeolian sand transport into in the upper reaches of the Yellow River as it flows along the eastern margin of the Ulan Buh Desert, which is a major desert in northern China. The present study is based on systematic monitoring of wind flow characteristics, aeolian sediment dynamics (saltation, creep and suspension), and the migration of typical sand dunes (mobile, semi-anchored, and anchored) from 2013 to 2016. The relationship between wind speed and wind-blown sand transport in the study area was determined. The relationship between the rate of aeolian sand transport (saltation and creep) and the wind speed 2 m above the ground surface can be depicted with a polynomial relation when the wind speed is ≥5.7 m/s, and with a power function when the wind speed is

Effect of binary surfactant mixtures on hydrophobic modification and moisture re-adsorption inhibition of lignite are investigated, along with that of dodecyltrimethylammonium bromide (DTAB), sodium dodecyl sulfonate (SDS) and dodecyl nonaethoxyl ether (C12(EO)9). Decrease in hydrophilicity of lignite is measured by determination of wetting heat and moisture re-adsorption rate of lignite before and after adsorbing surfactant. The differences in hydrophilicity change of lignite by using single and binary surfactant mixtures are discussed to disclose the synergistic or antagonism effect on hydrophobic modification of lignite. The experimental results show that, with adsorption of both single and binary mixtures of surfactants, lignite surface become hydrophobic. Compared to single component, DTAB-C12(EO)9 and DTAB-SDS display a higher efficiency on the hydrophilicity reduction and moisture re-absorption inhibition of lignite, while C12(EO)9-SDS does not. The calculated results indicate that there exists intermolecular synergism in the mixtures of DTAB-C12(EO)9 and DTAB-SDS, with forming synergetic aggregates “co-surfactant” DTAB-C12(EO)9 and DTAB-SDS, and C12(EO)9-SDS acts no synergism. These experimental results correspond to the calculation results of the properties of surfactant solution. Therefore, the solution properties of binary surfactant mixtures may provide a theoretical guiding in binary surfactant selection for reducing the hydrophilicity of lignite.

Despite the fact that copper (Cu) is a vital micronutrient to maintain body function, high doses of Cu through environmental exposure damage various organs, especially the liver, which is the main metabolic organ. To investigate the influence of long-term Cu-induced toxicity on mitophagy and apoptosis in rat liver, 96 seven-month-old male Sprague-Dawley rats were fed TBCC for 24 weeks. The results revealed that exposure to high Cu concentrations could promote oxidative stress liver injury by increasing the hepatic function index (ALT, AST and ALP) and MDA content, while reducing the activity of antioxidant enzymes (T-SOD, GSH-Px and CAT) related to oxidative stress. Consistent with histopathological observations, proper dietary Cu (15–60 mg/kg) could improve antioxidant stress levels and induce a dose-dependent increase in the mRNA expression of mitophagy-related genes, whereas a high Cu concentration (120 mg/kg) could cause severe liver impairment and ultrastructural changes and a reduction in mitophagosomes, accompanied by downregulation of Atg5, Beclin1, Pink1, Parkin, NIX, P62 and LC3B. The expression of apoptosis-related genes (Bax, Bax/Bcl-2, Caspase3, Cytc and p53) and proteins (Caspase3 and p53) was upregulated with the addition of dietary Cu. The results demonstrated that an appropriate dose of TBCC could improve liver function by promoting mitophagy and Cu enzymes that play antioxidative roles, while the accumulation of excess Cu could induce liver lesions by enhancing apoptosis and inhibiting mitophagy pathways.

Fluorine (F) and its compounds produced from industrial production and coal combustion can cause air, water and soil contamination, which can accumulate in animals, plants and humans via food chain threatening public health. Fluoride exposure affects liver, kidney, gastrointestinal and reproductive system in humans and animals. Literature regarding fluoride influence on intestinal structure and microbiota composition in ducks is scarce. This study was designed to investigate these effects by using simple and electron microscopy and 16S rRNA sequencing techniques. Results indicated an impaired structure with reduced relative distribution of goblet cells in the fluoride exposed group. Moreover, the gut microbiota showed a significant decrease in alpha diversity. Proteobacteria, Firmicutes and Bacteroidetes were the most abundant phyla in both control and fluoride-exposed groups. Specifically, fluoride exposure resulted in a significant decrease in the relative abundance of 9 bacterial phyla and 15 bacterial genera. Among them, 4 phyla (Latescibacteria, Dependentiae, Zixibacteria and Fibrobacteres) and 4 genera (Thauera, Hydrogenophaga, Reyranella and Arenimonas) weren't even detectable in the gut microbiota of the ducks. In summary, higher fluoride exposure can significantly damage the intestinal structure and gut microbial composition in ducks.

Heat shock proteins are molecular chaperones that are involved in numerous normal cellular processes and stress responses, and heat shock factors are transcriptional activators of heat shock proteins. Heat shock factors and heat shock proteins are coordinated in various biological processes. The regulatory function of heat shock factors in the expression of genes encoding heat shock proteins (Hsps) has been documented in some model insects, however, the role of transcription factors in modulating Hsps in other insects is still limited. In this study, one heat shock factor gene (AhHsf) was isolated and its two potential target genes (AhHsp70 and AhsHsp21) were confirmed from Agasicles hygrophila. AhHsf sequence analysis indicated that it belongs to the Hsfs gene family. RT-qPCR showed that expression levels of heat shock factors and of two heat shock proteins significantly increased under heat stress. Injection with double-stranded Hsf RNA in freshly emerged adult beetles significantly inhibited expression of AhHsp70 and AhsHsp21, shortened the adult survival, drastically reduced egg production, and ultimately led to a decrease in fecundity. RNA interference (RNAi)-mediated suppression of AhHsp70 or AhsHsp21 expression also significantly affected expression of AhHsf. Our findings revealed a potential transcriptional function of AhHsf to regulate expression of AhHsp70 and AhsHsp21, which may play a key role in A. hygrophila thermotolerance. Our results improve our understanding of the molecular mechanisms of the AhHsf - AhHsps signaling pathway in A. hygrophila.

Background The yield of microalgae biomass is the key to affect the accumulation of fatty acids. A few microalgae can assimilate organic carbon to improve biomass yield. In mixotrophic cultivation, microalgae can use organic carbon source and light energy simultaneously. The preference of the main energy source by microalgae determines the biomass yield. Auxenochlorella protothecoides is an oleaginous mixotrophic microalga that can efficiently assimilate glucose and accumulate a large amount of biomass and fatty acids. The current study focused on the effect of light on the growth and glucose assimilation of A. protothecoides. Results In this study, we found that the uptake and metabolism of glucose in A. protothecoides could be inhibited by light, resulting in a reduction of biomass growth and lipid accumulation. We employed comparative proteomics to study the influence of light on the regulation of glucose assimilation in A. protothecoides. Proteomics revealed that proteins involving in gene translation and photosynthesis system were up-regulated in the light, such as ribulose-phosphate 3-epimerase and phosphoribulokinase. Calvin cycle-related proteins were also up-regulated, suggesting that light may inhibit glucose metabolism by enhancing the production of glyceraldehyde-3-phosphate (G3P) in the Calvin cycle. In addition, the redox homeostasis-related proteins such as thioredoxin reductase were up-regulated in the light, indicating that light may regulate glucose uptake by changing the redox balance. Moreover, the increase of NADH levels and redox potential of the medium under illumination might inhibit the activity of the glucose transport system and subsequently reduce glucose uptake. Conclusions A theoretical model of how glucose assimilation in A. protothecoides is negatively influenced by light was proposed, which will facilitate further studies on the complex mechanisms underlying the transition from autotrophy to heterotrophy for improving biomass accumulation.

Ophraella communa is an effective bio-control agent of the invasive common weed. By now, the reference genes in O. communa have not yet been screened and validated. The aim of this study was to screen for the most stable reference genes in different backgrounds, such as different developmental stages, sexes, tissues, and male reproductive system with different body sizes. We selected 12 common housekeeping genes involved in different biological processes, including GAPDH, ACT1, ACT2, ARF1, ARF4, SDH, βTUBC, RPL4, RPL19, RPS18, EF1α, and COX as the candidate reference genes. To analyze the stability of the candidate reference genes, we first used three dedicated algorithms, GeNorm, NormFinder, and BestKeeper, and further comprehensive ranking was provided by ReFinder. The results showed that RPL19 and RPL4 exhibited the least variation in different developmental stages/sexes and in male reproductive systems with different body sizes. COX proved to be most suitable for normalizing the gene expression levels in different tissues, and coincidentally, RPL19 was also found to be second in terms of stability in this study. To the best of our knowledge, this is the first study to identify suitable reference genes for analyzing gene expression in O. communa; thus, this study would lay the foundation for future research on the molecular physiology and biochemistry of O. communa and other insects.

To explore the effects of copper (Cu) on energy metabolism and AMPK-mTOR pathway-mediated autophagy in kidney, a total of 240 one-day-old broiler chickens were randomized into four equal groups and fed on the diets with different levels of Cu (11, 110, 220, and 330 mg/kg) for 49 d. Results showed that excess Cu could induce vacuolar degeneration and increase the number of autophagosomes in kidney, and the adenosine triphosphate (ATP) level and mRNA levels of energy metabolism-related genes were decreased with the increasing dietary Cu level. Moreover, immunohistochemistry and immunofluorescence showed that the positive expressions of Beclin1 and LC3-II were mainly located in cytoplasm of renal tubular epithelial cells and increased significantly with the increasing levels of Cu. The mRNA levels of Beclin1, Atg5, LC3-I, LC3-II, Dynein and the protein levels of Beclin1, Atg5, LC3-II/LC3-I and p-AMPKα1/AMPKα1 were markedly elevated in treated groups compared with control group (11 mg/kg Cu). However, the mRNA and protein levels of p62 and p-mTOR/mTOR were significantly decreased with the increasing levels of Cu. These results suggest that impaired energy metabolism induced by Cu may lead to autophagy via AMPK-mTOR pathway in kidney of broiler chickens.

Copper (Cu) is a necessary trace mineral due to its biological activity. Excessive Cu can induce inflammatory response in humans and animals, but the underlying mechanism is still unknown. Here, 240 broilers were used to study the effects of excessive Cu on oxidative stress and NF-κB-mediated inflammatory responses in immune organs. Chickens were fed with diet containing different concentrations of Cu (11, 110, 220, and 330 mg of Cu/kg dry matter). The experiment lasted for 49 days. Spleen, thymus, and bursa of Fabricius (BF) on day 49 were collected for histopathological observation and assessment of oxidative stress status. Additionally, the mRNA and protein levels of NF-κB and inflammatory cytokines were also analyzed. The results indicated that excess Cu could increase the number and area of splenic corpuscle as well as the ratio of cortex and medulla in thymus and BF. Furthermore, excessive Cu intake could decrease activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px); but increase contents of malondialdehyde (MDA), TNF-α, IL-1, IL-1β; up-regulate mRNA levels of TNF-α, IFN-γ, IL-1, IL-1β, IL-2, iNOS, COX-2, NF-κB and protein levels of TNF-α, IFN-γ, NF-κB, p–NF–κB in immune organs. In conclusion, excessive Cu could cause pathologic changes and induce oxidative stress with triggered NF-κB pathway, and might further regulate the inflammatory response in immune organs of chicken.

The Upper Paleozoic in the north part of Tianhuan depression in the Ordos Basin, NW China has lower hydrocarbon generation intensity and complex gas-water relationship, the main factors controlling the formation of tight sandstone gas and the distribution of tight sandstone gas in the low hydrocarbon generation intensity area are studied. Through two-dimensional physical simulation experiment of hydrocarbon accumulation, analysis of reservoir micro-pore-throat hydrocarbon system and dissection of typical gas reservoirs, the evaluation models of gas injection pressure, reservoir physical property, and gas generation threshold were established to determine the features of tight gas reservoirs in low hydrocarbon intensity area: (1) at the burial depth of less than 3 000 m, the hydrocarbon generation intensity of (7−10)×108 m3/km2 is high enough to maintain effective charging; (2) tight sandstone in large scale occurrence is conducive to accumulation of tight gas; (3) differences in reservoir physical property control the distribution of gas pool, for the channel sandstone reservoirs, ones with better physical properties generally concentrate in the middle of sandstone zone and local structural highs; ones with poor physical properties have low gas content generally. Based on the dissection of the gas reservoir in the north Tianhuan depression, the formation of tight gas reservoirs in low hydrocarbon generating intensity area are characterized by “long term continuous charging under hydrocarbon generation pressure, gas accumulation in large scale tight sandstone, pool control by difference in reservoir physical property, and local sweet spot”, and the tight gas pools are distributed in discontinuous “sheets” on the plane. This understanding has been proved by expanding exploration of tight sandstone gas in the north Tianhuan depression. Key words: Ordos Basin, Tianhuan depression, hydrocarbon generation intensity, tight sandstone gas, reservoir-forming mechanism, distribution pattern

The poor flotation behavior of low-rank coal is mainly caused by the high content of functional oxygen groups present on the coal surface. Polar collectors, especially oxygenated collectors, play a significant role in the flotation enhancement of low-rank coal. In this study, to improve the low-rank coal flotation performance, octanoic acid was selected as a polar collector and the corresponding promotion mechanism was investigated at the molecular scale theoretically. The flotation results showed that an increased low-rank coal flotation response can be obtained by using an octanoic acid collector compared to a nonpolar dodecane collector. To obtain a molecular-level explanation of this phenomenon, a method of density functional theory (DFT) combined with molecular dynamics simulation was employed to explore the involved micro-mechanism. DFT calculation results suggested that the octanoic acid collector can interact with benzoic acid and phenol (representatives of oxygen-containing groups on the low-rank coal surface) through hydrogen bonding and repel water molecules present on benzoic acid and phenol. Based on theoretical calculations, in the presence or absence of water molecules, hydrogen bonding and electrostatic interactions are responsible for the strong affinity of octanoic acid to carboxyl group and hydroxyl group on the low-rank coal surface. Therefore, it was favorable for octanoic acid to form a stable adsorption layer on the low-rank coal surface, thus contributing to low-rank coal flotation significantly.

The alternative development of coal-bearing hydrocarbon source rocks and low-porosity and low-permeability tight sandstone reservoirs of the Triassic Xujiahe Formation in the Sichuan Basin is favorable for near-source hydrocarbon accumulation. The natural gas composition of the Xujiahe Formation in the Sichuan Basin is dominated by hydrocarbon gases, of which the methane content is 80.16%–98.67%. Typically, the C2+ content is larger than 5% in main wet gas. The dry gas is mainly distributed in the western and northern regions of the basin. The non-hydrocarbon gases mainly contain nitrogen, carbon dioxide, hydrogen, and helium, with a total content of δ13C4 occurs in some natural gas with a low evolution degree; such gas is mainly coal-related gas from humic-type source rocks of the Xujiahe Formation. As for the natural gas, δ2HCH4 values ranged from −195‰ to −161‰, δ2HC2H6 values ranged from −154‰ to −120‰, and δ2HC3H8 values ranged from −151‰ to −108‰. The dry coefficient, δ13C and δ2HCH4 are all positively correlated with the maturity of source rocks. The higher the maturity of source rocks is, the larger the natural gas dry coefficient is and the larger the δ13C and δ2HCH4 values are, indicative of the characteristic of near-source accumulation. The δ2HC2H6 value of natural gas is influenced by paleosalinity to a relatively large extent; the higher the paleosalinity is, the larger the δ2HC2H6 value is. The Pr/Ph value of the condensate oil ranged from 1.60 to 3.43, illustrating light oxidization–light reduction and partial-oxidization characteristics of the depositional environment of coal-bearing source rocks of the Xujiahe Formation. The natural gas light hydrocarbon (C5–C7) from the Xujiahe Formation presented two characteristics: the first was the relatively high aromatic hydrocarbon content (19%–32.1%), which reveals the characteristic of natural gas with humic substances of high-maturity; the second was the low content of aromatic hydrocarbon (0.4%–9.3%), reflecting water-washing during the accumulation of the natural gas. The reported research outcomes indicate a potential mechanism for natural gas accumulation in the Xujiahe Formation, which will further guide natural gas exploration in this region.

Copper is an important trace mineral in the diet of poultry due to its biological activity. However, limited information is available concerning the effects of high copper on mitochondrial dysfunction. In this study, 72 broilers were used to investigate the effects of high dietary copper on liver mitochondrial dysfunction and electron transport chain defect. Birds were fed with different concentrations [11, 110, 220, and 330 mg of copper/kg dry matter (DM)] of copper from tribasic copper chloride (TBCC). The experiment lasted for 60 d. Liver tissues on d 60 were subjected to histopathological observation. Additionally, liver mitochondrial function was recorded on d 12, 36, and 60. Moreover, a site-specific defect in the electron transport chain in liver mitochondria was also identified by using various chemical inhibitors of mitochondrial respiration. The results showed different degrees of degeneration, mitochondrial swelling, and high-density electrons in hepatocytes. In addition, the respiratory control ratio (RCR) and oxidative phosphorylation rate (OPR) in liver mitochondria increased at first and then decreased in high-dose groups. Moreover, hydrogen peroxide (H2O2) generation velocity in treated groups was higher than that in control group, which were magnified by inhibiting electron transport at Complex IV. The results indicated that high dietary copper could decline liver mitochondrial function in broilers. The presence of a site-specific defect at Complex IV in liver mitochondria may be responsible for liver mitochondrial dysfunction caused by high dietary copper.

A hybrid implicit–explicit-finite-difference time-domain (HIE-FDTD) method is modified to simulate the graphene. In this method, both the intraband and interband conductivity of grahene are considered. A simple Pade fit method is used to represent the interband conductivity which has complex relation with the angular frequency, and is incorporated into the HIE-FDTD method directly through an auxiliary difference equation. An infinite graphene sheet is simulated using presented technique and the result is compared with that of the conventional FDTD scheme and theoretical value. The results show that the HIE-FDTD method has excellent computational accuracy and considerably higher computational efficiency than FDTD scheme. Besides, the numerical example presents that the interband conductivity of the graphene has important effect on the numerical result at high frequency range, especially when the chemical potential is small.

The interband conductivity of graphene approximated by using Pade fit method is incorporated into the alternating-direction implicit finite difference time domain (ADI-FDTD) method to simulate graphene. The accuracy of the Pade fit method is verified. The ADI-FDTD method is unconditionally stable, so its computational efficiency is greatly larger than that of FDTD method, which is validated by numerical example. Besides, it shows that the interband conductivity of graphene has important effect on numerical result at high frequency range, especially when chemical potential is small.

The quality of canola oil was aimed during prolonged frying was detected by near-infrared spectroscopy (NIR spectroscopy). Results showed that the quality of canola oil after prolonged frying could be judged by NIR combined with statistical methods. In addition, the accuracy of the three classification methods used in this study is over 90%. And the classification results are relatively close to those of chemical value detection. This study may provide a means of rapidly and accurately to identify whether vegetable oil is safe to eat after prolonged frying.

Chemosensory proteins (CSPs) are considered to be the transporter linking odorant chemicals and receptors on sensory neurons. However, the extensive expression patterns of CSPs in insects suggest that CSPs are also involved in other physiological processes; the range of their functions, however, remains uncertain. In this study, we successfully characterized and cloned the CSP12 of Ophraella communa (OcomCSP12). The open reading frame of OcomCSP12 encodes 131 amino acids, with four conserved cysteine residues. The expression patterns of OcomCSP12 validated by quantitative real-time PCR (qRT-PCR) showed that OcomCSP12 is specifically expressed in female ovary. Furthermore, compared with the control treatment, silencing OcomCSP12 resulted in significantly reduced oviposition in females. Surprisingly, the knock-down rate of OcomCSP12 exceeded 95% and remained depressed for more than 15 days, indicating that RNA interference (RNAi) was a suitable method for exploring the function of CSP12 in O. communa. These findings increase our understanding of the expression profile and function of the CSP gene family in insects.

Invasive plant species may alter soil nutrient availability to facilitate their growth and competitiveness. However, the roles and functional mechanisms of plant-associated microbes that mediate these soil biogeochemical cycles remain elusive. Here, we studied how soil microorganisms and their functional processes differed between soils invaded by Ageratina adenophora and adjacent non-invaded soils in a region of China with heavy invasion. Our results indicated that soil nitrogen contents were over 4.32 mg/kg higher (p 0.05) in both rhizosphere soils and bulk soils dominated by A. adenophora as compared with those in soils dominated by non-invaded plants. Concurrently, soil microbial-mediated functional processes, i.e. nitrogen fixation rate, nitrification rate and ammonification rate, were also significantly (p 0.05) higher in either rhizosphere soils or bulk soils of invasive A. adenophora. Using a functional gene microarray, we found higher relative abundances of soil microbial genes involved in N cycling processes in A. adenophora soils, e.g. nifH, required for nitrogen fixation, which significantly correlated with ammonia contents (r = 0.35 in bulk soils, r = 0.37 in rhizosphere soils, p 0.05) and the nitrogen fixation rate (r = 0.44, p 0.05). We also found that the relative abundances of labile carbon decomposition genes were higher in invasive A. adenophora soils, implying a potential higher availability of carbon. These results suggest that the soil surrounding the invasive plant A. adenophora is a self-reinforcing environment. The plant litter and rhizosphere environment of the invasive may influence soil microbial communities, promoting self-supporting soil processes. Alternatively, the regions invaded by A. adenophora may have already had properties that facilitated these beneficial microbial community traits, allowing easier invasion by the exotics. Both scenarios offer important insights for the mitigation of plant invasion and provide an ecosystem-level understanding of the invasive mechanisms utilized by alien plants.

Among different synthetic compounds copper (Cu) is persistently and frequently used as growth promoter, antibacterial, antifungal and antiparasitic agent and has become common environmental pollutant. Therefore, this study explores the cardio-toxic effects of control group (10 mg/kg bw Cu) and treatment group (125 and 250 mg/kg bw Cu), and it association with process of autophagy and metabolomics in myocardium of pigs kept in three different experimental treatments for a period of 80 days. The results of serum biochemical parameters showed a significantly increase in creatinine kinase (CK), creatine kinase-MB (CK-MB), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and aspartate aminotransferase (AST) in pigs exposed to 125 mg/kg bw and 250 mg/kg bw Cu. Meanwhile, the severe structural abnormalities in cardiomyocytes were found when exposed to 250 mg/kg Cu at day 80. In addition, the mRNA and proteins (Beclin1, ATG5 and LC3II) expression levels were significantly increased and p62 was significantly decreased in cardiomyocytes exposed to 250 mg/kg Cu at day 80 of the trial. Further, UPLC-QTOF/MS technique showed that 7 metabolites were up-regulated and 37 metabolites were down-regulated in cardiomyocytes after 250 mg/kg Cu treatment, with a principal impact on the metabolic pathways including glycerophospholipid metabolism, one carbon pool by folate, fatty acid elongation and fatty acid degradation, which were related to autophagy. Overall, our study identified the autophagy processes and metabolites in metabolic pathways in Cu-induced myocardium injury, which provided useful evidence of myocardium toxicity caused by Cu exposure via metabolomics and multiple bioanalytic methods.

Numerous oxygen-containing groups present on the low rank coal (LRC) surface makes a poor flotation performance of LRC only using common oily collector. Increasing the spreading strength of oily collector on the LRC surface is of great significance for improving its flotation behavior. In this study, molecular dynamics simulation (MDS) was employed to investigate the microscopic spreading characteristics of non-polar oil droplet on the LRC surface. For this purpose, the configurations of non-polar oil droplet, spreading area, and interaction energy were calculated. It was found that on the raw LRC surface, the non-polar oil droplet remained spherical with a small spreading area and weak interaction strength. Besides, a non-ionic surfactant, dodecyl nonaethoxyl ether (C12EO9) was used to modify the surface wettability of LRC to enhance the non-polar oil droplet spreading. After surfactant pretreatment, a pancake-like oil film was formed on the LRC surface with a larger spreading area and more negative interaction energy compared with the case of the raw LRC surface. Based on these observations, the microscopic insights were provided about the spreading of non-polar oil droplet on the surface of LRC, as well as the role of surfactant enhancing its spreading intensity. In addition, the effect of the oxygen-containing groups on the spreading behaviors of non-polar oil droplet was also explored. The results suggested that carboxyl and hydroxyl are the main groups that hinder the spreading of the non-polar oil droplet on LRC surface. The simulation results are in accordance with the available experimental data.

In this work, a combined molecular dynamics (MD) simulations and experiments were adopted to study the microscopic mechanism of the benzene ring in nonionic surfactants on low-rank coal (LRC) flotation. Two nonionic surfactants with identical headgroups, nonylphenol ethoxylate (NPEO) and dodecyl ethoxyl ethers (C12EO), were selected as the research objects. Two LRC surface models with varying metamorphism degrees were constructed. The rationality of the constructed surface models was firstly discussed from the chemical composition and structure. The morphology of the surfactants and the adsorption energy obtained by MD suggested that the arrangement of polar oxygen atoms in the surfactant depended on its interaction with the polar groups of LRC, and the presence of the benzene ring in the nonionic surfactant hardly changed its arrangement on the LRC surface. The benzene ring in the nonionic surfactant can enhance its adsorption on the higher rank coal surface via the π-bonds while it cannot promote its adsorption on the lower rank coal surface. The results obtained from the experiments are in accordance with the simulation results.

To study the effects of nonionic surfactants polarity on the quality of flotation clean low-rank coal (LRC), three nonionic surfactants of different polarity, n-dodecyl β-D-maltoside (DDM), nonylphenol ethoxylate (NPEO) and dodecyl ethoxyl ethers (C12EO) were selected and their flotation behaviors were experimentally investigated. By analysing the adsorption behaviors of surfactants and interfacial water on the kaolinite (0 0 1) surface and (0 0 1 ¯ ) surface, it could be concluded that the three surfactants could not replace the water molecules adsorbed on kaolinite (0 0 1) surface due to the strong adsorption between the water molecule and the kaolinite (0 0 1) surface. And the ability of the three surfactants to replace the water molecules adsorbed on kaolinite (0 0 1 ¯ ) surface is as follow: DDM > NPEO > C12EO, i.e. increasing the polarity of surfactants makes it easier to adsorb on kaolinite surface. In addition, the surfactants adsorption layer on kaolinite (0 0 1 ¯ ) surface is more compact with the increase in nonionic surfactant polarity. The results of simulations are in according with the experimental data. The presented study offers directions in surfactant selection and design in LRC cleaning.

The influence of water in samples on matrix effects and recoveries of analytes were investigated during the determination of residues of nine beta-agonists including salbutamol, terbutaline, cimaterol, fenoterol, clorprenaline, ractopamine, tulobuterol, clenbuterol, and penbuterol in porcine liver, muscle, and urine samples with liquid chromatography tandem mass spectrometry. Lyophilization procedure was adopted for sample moisture removal. The results showed that there were weak suppression effects for all target analytes except ractopamine, and no significant differences were found between fresh and lyophilized samples with respect to matrix effects of nine beta-agonists (P > 0.05). However, most analytes’ recoveries in the range of 85.0–115 % were obtained in lyophilized samples, while only a few ones were found in fresh samples. There are significant differences in recoveries for most analytes between fresh and lyophilized samples (P

Copper (Cu) is an essential trace element that is required for the catalysis of several cellular enzymes. Excessive Cu could induce hepatotoxicity in humans and multiple animals. The purpose of this study was to investigate the effects of autophagy machinery on Cu-induced hepatotoxicity. Chicken hepatocytes were cultured in medium in the absence and presence of Cu sulfate (CuSO4) (0, 10, 50, and 100 μM) for 0, 6, 12, and 24 h, and in the combination of CuSO4 and N-acetyl-l-cysteine (NAC) (1 mM), rapamycin (10 nM), and 3-methyladenine (3-MA) (5 mM) for 24 h. Results showed that Cu could markedly increase the number of autophagosomes and LC3 puncta, induce autophagy-related genes (Beclin1, ATG5, LC3Ⅰ, LC3Ⅱ, mTOR, and Dynein) mRNA expression and proteins (BECN1, LC3Ⅱ/LC3Ⅰ) expression. NAC could relieve Cu-induced the changes of above genes and proteins. Additionally, rapamycin attenuated Cu-induced the increased lactic dehydrogenase (LDH), aspartate amino transferase (AST), and alanine aminotransferase (ALT) activities, and SOD-1 mRNA expression as well as the decreased cell viability, reactive oxygen species (ROS), hydrogen peroxide, total superoxide dismutase (T-SOD), malonaldehyde (MDA), catalase (CAT), HO-1 mRNA expression, adenosine triphosphate (ATP) levels, mitochondrial mass, and mitochondria membrane potential (MMP). But 3-MA had the opposite effects on above factors. Collectively, these findings provide strong evidence that Cu could induce autophagy by generating excessive ROS in hepatocytes, and autophagy might attenuate Cu-induced mitochondrial dysfunction by regulating oxidative stress.

ρ-Cymene was one of the major components of volatiles released by croftonweed. The allelopthy of ρ-cymene on the growth of upland rice seedlings was performed. Hydrogen peroxide generation, malondialdehyde (MDA) content, proline content, total ascorbate (ascorbate/dehydroascorbate), reduced/oxidized glutathione, and the levels of induction of antioxidant enzyme were studied in the seedlings of upland rice. ρ-Cymene inhibited the growth of upland rice seedlings. Exposure of upland rice seedlings to ρ-cymene increased levels of H2O2, MDA, and proline, indicating lipid peroxidation and induction of oxidative stress. Activities of the antioxidant enzymes superoxide dismutase, catalase, peroxidase, guaiacol peroxidase, ascorbate peroxidase, and glutathione reductase were significantly elevated during the treatment period (7–15 d) compared with enzymes in the upland rice seedlings unexposed to ρ-cymene, thereby indicating the enhanced generation of reactive oxygen species (ROS) upon ρ-cymene exposure. These results suggest that activation of the antioxidant system by ρ-cymene led to the formation of ROS that resulted in cellular damage and decreased growth of upland rice seedlings.

Several volatile allelochemicals were identified and characterized from fresh leaf tissues of the invasive croftonweed. A simple bioassay was used to demonstrate the release of volatile allelochemicals from leaf tissues. The bioassays revealed that foliar volatile components of croftonweed exhibited significant effects on the seedling growth of upland rice. Peroxidase (POD) activity, superoxide dismutase (SOD) activity, and root oxidizability rose as the concentration of volatiles increased. Activity for both POD and SOD significantly increased with exposure to 15 g and 20 g of croftonweed leaf tissue for 5 d. Root activity was significant at 10 g compared to the control. The volatile components also stimulated the development of the aerenchyma tissue and inhibited lateral root formation. Leaf volatiles of croftonweed were identified by gas chromatography coupled with mass spectrometry (GC–MS). Some of the compounds identified included α-phellandrene, camphene, ρ-cymene, 2-carene, α-pinene, limonene, and (z)-3-hexen-1-ol. Bioassays showed that four of these compounds could account for the observed phytotoxicity imparted by total leaf volatiles. Limonene, 2-carene, α-pinene and camphene had no phytotoxic effect on shoot elongation. Phellandrene did cause inhibition in shoot growth at all concentrations. Both (z)-3-hexene-1-ol and ρ-cymene inhibited both shoot elongation and root elongation, but the effects of the two compounds on root length were more significant than on the shoot length.

Grassland ecosystems, an important component of the terrestrial environment, play an essential role in the global carbon cycle and balance. We considered four different grazing intensities on a Stipa breviflora desert steppe: heavy grazing (HG), moderate grazing (MG), light grazing (LG), and an area fenced to exclude livestock grazing as the Control (CK). The analyses of the aboveground biomass, litter, belowground biomass, soil organic carbon and soil light fraction organic carbon were utilised to study the organic carbon stock characteristics in the S. breviflora desert steppe under different grazing intensities. This is important to reveal the mechanisms of grazing impact on carbon processes in the desert steppe, and can provide a theoretical basis for conservation and utilisation of grassland resources. Results showed that the carbon stock was 11.98–44.51 g m–2 in aboveground biomass, 10.43–36.12 g m–2 in plant litters, and 502.30–804.31 g m–2 in belowground biomass (0–40 cm). It was significantly higher in CK than in MG and HG. The carbon stock at 0–40-cm soil depth was 7817.43–9694.16 g m–2, and it was significantly higher in LG than in CK and HG. The total carbon stock in the vegetation-soil system was 8342.14–10494.80 g m–2 under different grazing intensities, with the largest value in LG, followed by MG, CK, and HG. About 90.54–93.71% of the total carbon in grassland ecosystem was reserved in soil. The LG and MG intensities were beneficial to the accumulation of soil organic carbon stock. The soil light fraction organic carbon stock was 484.20–654.62 g m–2 and was the highest under LG intensity. The LG and MG intensities were beneficial for soil nutrient accumulation in the desert steppe.