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• FSDAF can better predict biomass changes. • Mapping the spatiotemporal distribution of grassland biomass(30 m, 8 days). • Biomass is closely related to altitude and water supply in the Xilin River Basin. • Biomass responds more to temperature changes than precipitation. Accurate estimation of aboveground biomass of grasslands is key to sustainable grassland utilization. However, most satellites cannot provide high temporal and spatial resolution data. Patterns of grassland dynamics associated with variability in climate conditions across spatiotemporal scales are yet to be adequately quantified. A spatiotemporal fusion model offers the opportunity to combine the resolution advantages of different remote sensing data to achieve a high frequency and high precision monitoring of vegetation. We test a flexible spatiotemporal data fusion (FSDAF) methodology to generate synthetic normalized difference vegetation index (NDVI) data from Moderate-Resolution Imaging Spectroradiometer (MODIS) and Landsat data sets. The methodology is tested for the semi-arid grassland of the Xilin River Basin, China. Based on NDVI data fusion and field measured aboveground biomass an aboveground biomass estimation model is established for the watershed. Exploring the temporal and spatial changes of biomass and its relationship with environmental factors. The results show that: (1) The FSDAF model performs well (R2 = 0.75) and has clear textural features. (2) The established Support Vector Machine Aboveground Biomass model not only ensured the accuracy of estimation (R2 = 0.78, RMSE = 15.43 g/m2), but also generated spatiotemporal maps of biomass with higher spatial (30 m) and temporal resolution (8 days). (3) The grassland aboveground biomass in this area decreases from southeast to northwest, and the grassland biomass reaches its peak at the end of July. The average biomass of different grasslands decreases in the order of meadow grassland > typical grassland > desert grassland. (4) Aboveground biomass increased linearly with increasing water content, organic carbon and total nitrogen, and was most sensitive to soil water content. During the early growing and rapid growing period, aboveground biomass is mainly affected by both air temperature and precipitation, while the effects of temperature and human activities gradually dominate in the middle and late growing periods. This study helps to improve the spatial and temporal resolution of dynamic monitoring of grassland biomass, and provides a scientific basis for grassland protection and management in arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

Laminar methane/air premixed Bunsen flames were studied using detailed numerical simulations and laser diagnostics. In the numerical simulations one-dimensional and two-dimensional configurations were considered with detailed transport properties and chemical kinetic mechanism. In the measurements OH PLIF was employed. The flame structures vary with varying equivalence ratio and pressure. For stoichiometric mixture at atmospheric pressure the flame exhibits a single reaction zone structure, while at high-pressures the flame exhibits a two-reaction zone structure: an inner premixed flame and an outer diffusion flame. The predicted two-zone structure is confirmed in the OH PLIF measurements. Using the numerical and the experimental data the methods of flame-cone-angle and flame-area have been used to extract the laminar flame speed for different equivalence ratios and pressures. It is found that although the flame cone angle method is widely used, it yields a lower accuracy than that of the flame surface area method. The inlet velocity of the burner is shown to affect the accuracy of extracted laminar flame speed. It is suggested that the most suitable inlet velocity of methane-air mixture is about 6 times the laminar flame speed. [ABSTRACT FROM AUTHOR]

A series of experiments were performed to investigate the relationship between syngas composition (H 2 /CO/CO 2 /N 2 /O 2 ) and NO formation. Laser-saturated fluorescence measurements of NO in a premixed syngas flat flame from a heat flux burner were recorded for various fuel compositions, dilution ratios and equivalence ratios. Quantitative measurements were compared with the predictions from CHEMKIN software using four different chemical mechanisms, i.e., GRI mech 3.0, Chemical Reaction Engineering and Chemical Kinetics 1407, GDF-Kin 3.0, and the Mendiara and Glarborg mechanism; each mechanism included reaction subsets for NO x formation. These models were validated against a CH 4 flame; the GDF-Kin 3.0 mechanism produced the best agreement with measurements. NO measurements for CO/H 2 syngas fuel with 50% CO 2 dilution at various equivalence ratios found the maximum NO production near stoichiometry. The majority of NO produced for these conditions is predicted to come from the combination of the NNH and N 2 O pathways. Investigation of NO production during combustion of different CO/H 2 ratio syngas diluted with 60% N 2 showed that increasing the H 2 fraction decreased the total NO concentration. However, normalizing the NO production rate by the fuel mass consumption rate showed H 2 produces more NO per gram of fuel consumed. Predictions of temperature and NO rate of production along the flame axis showed that the syngas with high H 2 content had a flame front closer to the burner exit and NO production rate greater than the high CO case. Dilution of CO/H 2 syngas fuel with N 2 and CO 2 showed that CO 2 has a stronger reduction in NO emission than N 2 . GDF-Kin 3.0 predicted that dilution with CO 2 caused a greater reduction in flame temperature than the same volume of N 2 . Predicted NO rate of production and reaction sensitivity analysis predicted that the Zel’dovich pathway was dominant for undiluted syngas. However, as the flame temperature reduced, the Zel’dovich pathway was inhibited to a greater extent than the N 2 O and NNH pathways so that, at high dilution, NO production was driven by the N 2 O and NNH pathways. [ABSTRACT FROM AUTHOR]

• HOTAIR expression was increased in cholangiocarcinoma. • HOTAIR deletion inhibited cholangiocarcinoma progression. • HOTAIR upregulated HMGB1 expression by sponging miR-204-5p. • HOTAIR promoted cholangiocarcinoma progression via miR-204-5p/HMGB1 axis. Cholangiocarcinoma (CCA) is a malignant tumor in the world. LncRNA HOX transcript antisense intergenic RNA (HOTAIR) was identified as a crucial regulator in various cancers including CCA. This study aimed to unravel the functions of HOTAIR and its biological mechanism in CCA, hinting for the new therapeutic targets in CCA. The levels of HOTAIR, miR-204-5p and HMGB1 in CCA tissues and cell lines (HuB28 and HuCCT1) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was conducted to detect the protein levels of LC3-I, LC3-II, Beclin-1 and HMGB1. The relationships among HOTAIR, miR-204-5p and HMGB1 were examined by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull down assay. Cell proliferation ability and apoptosis rate were assessed by CCK8 assay and flow cytometry, respectively. in vivo experiment was conducted to examine the bio-functions of HOTAIR in nude mice. HOTAIR and HMGB1 were over-expressed, while miR-204-5p was lowly expressed in CCA tissues and cells. The dual-luciferase reporter assay indicated that miR-204-5p was a target of HOTAIR, and HMGB1 was a target of miR-204-5p. The restoration experiments showed that HOTAIR repressed cell apoptosis, autophagy and promoted cell proliferation via miR-204-5p/HMGB1 axis. Additionally, HOTAIR silencing retarded the xenograft tumor growth by up-regulation of miR-204-5p and down-regulation of HMGB1. These data unraveled that lncRNA HOTAIR regulated HMGB1 to suppress cell apoptosis, autophagy and induce cell proliferation by sponging miR-204-5p in CCA. Thus, this new regulatory pathway may provide new therapeutic targets for CCA. [ABSTRACT FROM AUTHOR]

Leptin, an adipocyte-derived hormone, promotes liver fibrogenesis and inhibits the expression of peroxisome-proliferator activated receptor γ (PPARγ), a key transcription factor in inhibition of hepatic stellate cell (HSC) activation, in HSCs. This research aimed to further investigate the mechanisms underlying leptin regulation of PPARγ1 in HSCs in vivo and in vitro. Results demonstrated that sex-determining region Y-box 9 (Sox9) could bind to a site around − 2275 within leptin response region of PPARγ1 promoter and inhibited PPARγ1 expression. Sox9 upregulated the expressions of α1(I)collagen and alpha-smooth muscle actin in HSCs. Leptin stimulated Sox9 expression and Sox9 binding to PPARγ1 promoter. The signaling pathways of NADPH oxidase, β-catenin, and delta-like homolog1 (DLK1) mediated leptin upregulation of Sox9 expression. Moreover, there existed crosstalk between NADPH oxidase pathway and β-catenin or DLK1 signaling pathway. Human liver specimens of cirrhosis were shown to be of a large number of the positive HSCs for p47phox (playing a central role in NADPH oxidase activity), 4-hydroxynonenal (a lipid peroxidation product), Sox9, and α-smooth muscle actin whereas PPARγ-positive HSCs were rarely detected. These results might deepen understanding of the molecular mechanisms for leptin inhibition of PPARγ1 expression in HSCs and for the liver fibrosis associated with leptin. [ABSTRACT FROM AUTHOR]

The ozone (O 3 ) decomposition in the pre-heat zone of flames can initiate and accelerate the chain-branching reactions. In the present study, formaldehyde (CH 2 O) was investigated by both experiment and simulation methods in methane/air laminar premixed flames under atmospheric conditions. The formaldehyde concentration profiles in the flames were measured with CH 2 O-PLIF. When 4500 ppm of ozone was added, the formaldehyde concentration in Bunsen type laminar flame was enhanced by 58.5% at fuel-rich condition ( ϕ = 1.4) and 15.5% at stoichiometric condition. In the simulation work, the most recent ozone sub-mechanism was coupled with GRI-mech 3.0 kinetic mechanism. It showed that with 4500 ppm ozone addition, the formaldehyde concentration was enhanced by about 48.1% at rich condition ( ϕ = 1.4) and about 14.7% in stoichiometric mixture. The simulation suggested an early production of CH 2 O with ozone addition, especially in rich conditions. These reactions occurred at relatively low temperature, around 500 K. In order to isolate these reactions from the flame, experiments with preheated unburned mixtures were carried out. A larger amount of formaldehyde was produced in the zone far from the flame as the preheating temperature was increased. It indicated that the combustion enhancement with ozone could be caused by the additional reactions of ozone at relatively low temperature. Simulations showed that methoxy radical (CH 3 O) is the key specie for production of formaldehyde at lower temperatures. Early in the pre-heat zone of the laminar flame, formaldehyde occurs via decomposition of CH 3 O while in the pre-heated gas mixture via reaction of CH 3 O with O 2 . Furthermore, the O 3 effect on turbulent flames was investigated showing a greater enhancement in formaldehyde signal than that in the laminar cases. This difference in formaldehyde signal enhancement could be attributed to the expansion of the preheat zone, due to turbulence. [ABSTRACT FROM AUTHOR]

Hepatic stellate cell (HSC) activation is a crucial step in the development of liver fibrosis. Peroxisome-proliferator activated receptor γ (PPARγ) exerts a key role in the inhibition of HSC activation. Leptin reduces PPARγ expression in HSCs and plays a unique role in promoting liver fibrosis. The present studies aimed to investigate the mechanisms underlying leptin regulation of PPARγ1 (a major subtype of PPARγ) in HSCs in vivo and in vitro. Results revealed a leptin response region in mouse PPARγ1 promoter and indicated that the region included a GATA binding protein binding site around position − 2323. GATA binding protein-2 (GATA-2) could bind to the site and inhibit PPARγ1 promoter activity in HSCs. Leptin induced GATA-2 expression in HSCs in vitro and in vivo. GATA-2 mediated leptin inhibition of PPARγ1 expression by its binding site in PPARγ1 promoter in HSCs and GATA-2 promoted HSC activation. Leptin upregulated GATA-2 expression through β-catenin and sonic hedgehog pathways in HSCs. Leptin-induced increase in GATA-2 was accompanied by the decrease in PPARγ expression in HSCs and by the increase in the activated HSC number and liver fibrosis in vivo. Our data might suggest a possible new explanation for the promotion effect of leptin on liver fibrogenesis. [ABSTRACT FROM AUTHOR]

Highlights: [•] The effect of high yield pulp (HYP) content on coated paper print quality was investigated. [•] The image quality from the two paper samples is related to the pressroom operations. [•] The coated paper containing HYP can have similar print quality. [Copyright &y& Elsevier]

Soil infiltration is an inevitable process of the mutual transformation of surface water and groundwater in the ecological hydrologic cycle that helps to transport nutrients required by plants to the root system, thus promoting vegetation growth and maintaining ecological stability. It is of utmost importance to simulate the process of soil infiltration and calculate the key parameters of soil water migration accurately. Yet, a scale effect in the determination of soil infiltration can seldom be avoided. Based on the scale effect law caused by a change in the inner-ring diameter of the double-ring infiltrometer and common infiltration models, empirical models of soil infiltration scale transfer (SIST) are proposed and established to improve the simulation accuracy of the steady infiltration rate, while reducing test difficulty and consumption. The results show that the four SIST models established based on the infiltration models well simulate the infiltration process of five different sizes of double-ring infiltrometers. The simulation Adj - R 2 of the three infiltration zones in the study area was between 0.66 and 0.95, and the validation Adj - R 2 ranged from 0.72 to 0.94, indicating that the SIST models showed good applicability in the investigated semi-arid grassland. The results further showed that the double-ring infiltrometer with an inner-ring diameter larger than 90 cm and an outer ring buffer coefficient of 0.33 was not accompanied by the scale effect during measurement. Moreover, the SIST models were used to predict the steady infiltration rate in the study area, providing an accurate data basis for the establishment of regional eco-hydrological models. • SIST functions for double ring infiltration with different bi and di were proposed. • Suitable inner ring diameters can ensure the accuracy and reduce consumption. • Final infiltration rate free from infiltrometer scale effect is predicted. [ABSTRACT FROM AUTHOR]