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As a common inflammatory bowel disease, ulcerative colitis (UC) is featured with inflammation, oxidative damage, and the impairment of intestinal mucosal barrier, which bring threat to patients' quality of live. Hinesol, derived from Atractylodes lancea, is a unique sesquiterpenoid. Our study proposed to survey the effects and mechanism of hinesol in UC. UC mouse model was constructed using dextran sulfate sodium (DSS). Lipopolysaccharide (LPS) was applied for RAW264.7 cells stimulation to construct cell inflammatory model. The changes of disease activity index (DAI), body weight, colon length, and intestinal pathology in mice were analyzed to estimate the severity of colitis. Enzyme-linked immunosorbent assay was applied to check the changes of interleukin (IL)-1β, IL-18, IL-6, and tumor necrosis factor (TNF)-α. The levels of myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione peroxidase (GSH-px), catalase (CAT), and malondialdehyde (MDA) were estimated by corresponding reagent kit. The changes of phosphorylated (p)-NF-κB P65, and p-IκBα, ZO-1, Occludin, Claudin-1, Src, XCL1, CCL2, and CXCL16 protein were examined using western blot. Flow cytometry and cell counting kit-8 assay were utilized for assessment of cell apoptosis and viability. We found that DSS reduced mice body weight, increased DAI, shorten colon length, and led to severe enteric mucosal injury, while hinesol improved the above symptoms induced by DSS. In DSS mice, hinesol raised the levels of ZO-1, Occludin, Claudin-1, SOD, GSH-px, and CAT and decreased the levels of TNF-α, IL-18, IL-1β, IL-6, MPO, and MDA. Additionally, in DSS mice and LPS-stimulated RAW264.7 cells, hinesol inhibited the high expression of Src, XCL1, CCL2, CXCL16, p-NF-κB P65, and p-IκBα. The molecular docking showed that there was a good interaction between hinesol and Src. Moreover, in LPS-stimulated RAW 264.7 cells, Src overexpression partially reversed the inhibition of hinesol on cell apoptosis, pro-inflammatory factors, and oxidative stress. In conclusion, hinesol alleviated DSS-induced colitis, which might have a bearing on the inhibition of Src-mediated NF-κB and chemokine signaling pathway. [ABSTRACT FROM AUTHOR]

Diamondoid compounds are widely used to reflect thermal maturation of high mature source rocks or oils and oil cracking extents. However, diamondoids and thiadiamondoids were demonstrated to have newly been generated and decomposed in our hydrothermal pyrolysis of crude oil and TSR experiments. Our results show that adamantanes and diamantanes are generated primarily within the maturity range 0.48–2.1% and 1.2–3.0% EasyRo, respectively. Their formation is enhanced and the decomposition of diamantanes obviously lags at elevated temperatures compared with anhydrous experiments. MDI, EAI, DMAI-1, DMDI-2 may serve as reliable maturity proxies at > ca.1.0% EasyRo, and other isomerization indices (TMAI-1, TMAI-2 and DMAI-2) are effective for the highly mature organic matter at EasyRo > 2.0%. The extent of oil cracking (EOC) calculated from the broadly used (3- + 4-) MD method (Dahl et al. in Nature 399:54–56, 1999) is proven to overestimate, especially for highly cracked samples due to the new generation of (3- + 4-) MD. Still, it can be corrected using a new formula at < 3.0% EasyRo. Other diamondoid-related indices (e.g., EAI, DMDI-2, As/Ds, MAs/MDs, DMAs/DMDs, and DMAs/MDs) can also be used to estimate EOC. However, these indices cannot be applied to TSR-altered petroleum. TSR is experimentally confirmed to generate diamantanes and thiaadmantanes at 1.81% EasyRo likely via direct reactions of reduced S species with hydrocarbons and accelerate the decomposition of diamantanes at > 2.62% EasyRo compared with thermal chemical alteration (TCA). More studies are needed to assess specific mechanisms for the formation of thiadiamondoids under natural conditions. [ABSTRACT FROM AUTHOR]

These authors contributed equally: Leiying Miao, Chao Liu Correction to: Cell Biochemistry and Biophysics (2014) 69:663-672 https://doi.org/10.1007/s12013-014-9849-z published online 22 February 2014 After publication of original article, it came to author's attention that Figure 1c, Figure 2 a, b and Figure 3 were incorrectly given. Graph Graph Graph. [Extracted from the article]

Small molecule kinase inhibitors (SMKIs) are being approved at a fast pace under expedited programs for anticancer treatment. In this study, we construct a multi-domain dataset from a total of 4638 patients in the registrational trials of 16 FDA-approved SMKIs and employ a machine-learning model to examine the relationships between kinase targets and adverse events (AEs). Internal and external (datasets from two independent SMKIs) validations have been conducted to verify the usefulness of the established model. We systematically evaluate the potential associations between 442 kinases with 2145 AEs and made publicly accessible an interactive web application "Identification of Kinase-Specific Signal" (https://gongj.shinyapps.io/ml4ki). The developed model (1) provides a platform for experimentalists to identify and verify undiscovered KI-AE pairs, (2) serves as a precision-medicine tool to mitigate individual patient safety risks by forecasting clinical safety signals and (3) can function as a modern drug development tool to screen and compare SMKI target therapies from the safety perspective. Small molecule kinase inhibitors (SMKIs) are being approved at a fast pace under expedited programs for anticancer treatment. Here, the authors employ a machine-learning model to examine the relationships between kinase targets and adverse events in the trials of 16 FDA-approved SMKIs. [ABSTRACT FROM AUTHOR]

For identifying the occurrence and extent of thermochemical sulfate reduction (TSR) reaction of natural gas and better understanding the chemical and carbon isotopic variations in natural gas reservoirs, high-pressure hydro-pyrolysis with a special designed apparatus was performed using natural gas and various amounts of MgSO4·7H2O at up to 360 °C. The yields, chemical and isotopic compositions of the gases produced during TSR and thermal cracking were measured. As the extent of TSR reaction increased, the concentrations of CH4, CO2 and H2S increased in a nonlinear way, while those of C2H6 and C3H8 decreased. According to the variation of gas content, the TSR reaction of alkane gases can be divided into an uncatalyzed and a catalyzed stage, which is different from previous studies that treated the TSR reaction of alkane gases as a non-autocatalytic reduction process. As the concentration of MgSO4·7H2O increased, the rate of TSR reaction with hydrocarbon gases increased. The concentrations of HSO4− and volume of aqueous phase could be responsible for the different TSR reaction rates in the catalyzed stage. The co-variation of ln(C1/C2) and ln(C2/C3) could be related to the TSR reaction of alkane gases. Our study provides clues for understanding the compositional variations in natural conditions. [ABSTRACT FROM AUTHOR]

Isotopic rollover refers to that δ13C value of a gas component decreases with maturity. Its occurrence is closely related to high productivity of shale gas. Isothermal confined pyrolysis experiments (gold capsules) were performed to simulate this phenomenon on whole rock Lucaogou and kerogens Saergan, Wuerhe and Fengcheng in the absence (anhydrous) and presence of added water (hydrous) at 50 MPa, 372 °C and heating duration 0–672 h, corresponding to 0.96–1.85 EASY%Ro. For kerogen Saergan isolated from source rock with hydrogen index (HI) 159 mg/g TOC and 1.10–1.30% Ro equivalent, none of δ13C1, δ13C2 and δ13C3 showed any rollover in both anhydrous and hydrous experiments. For Lucaogou whole rock with HI 856 mg/g TOC and 0.50–0.60%Ro, both δ13C2 and δ13C3 showed rollover in anhydrous experiments while all δ13C1, δ13C2 and δ13C3 showed rollover with greater magnitude in hydrous experiments starting at 1.49–1.64 EASY%Ro. For kerogens Wuerhe and Fengcheng isolated from source rocks with HI of 550 and 741 mg/g TOC, and 1.18 and 0.96%Ro respectively, both δ13C2 and δ13C3 demonstrated rollover in anhydrous experiments while only δ13C2 showed rollover with minor magnitude in hydrous experiments starting at 1.47–1.53 EASY%Ro. The different effects of water on isotopic rollover among samples Lucaogou, Wuerhe and Fengcheng can be ascribed to rate related isotopic fractionation. Higher generation rate leads to minor isotopic fractionation and rollover magnitude. It was suggested that isotopic rollover likely occurs in a source rock having higher amount of initial retained oil prior to bulk oil cracking and currently within the major stage of oil-cracking to gas (1.50–2.00%Ro). [ABSTRACT FROM AUTHOR]

The global carbon cycle has played a key role in mitigating global warming and climate change. Long-term natural and anthropogenic processes influence the composition, sources, burial rates, and fluxes of carbon in sediments on the continental shelf of China. In this study, the rates, fluxes, and amounts of carbon storage at the centennial scale were estimated and demonstrated using the case study of three fine-grained sediment cores from the central South Yellow Sea area (SYSA) and Min-Zhe belt (MZB), East China Sea. Based on the high-resolution temporal sequences of total carbon (TC) and total organic carbon (TOC) contents, we reconstructed the annual variations of historical marine carbon storage, and explored the influence of terrestrial and marine sources on carbon burial at the centennial scale. The estimated TC storage over 100 years was 1.18×108 t in the SYSA and 1.45×109 t in the MZB. The corrected TOC storage fluxes at the centennial scale ranged from 17 to 28 t/(km2·a)in the SYSA and from 56 to 148 t/(km2·a) in the MZB. The decrease of terrestrial materials and the increase of marine primary production suggest that the TOC buried in the sediments in the SYSA and MZB was mainly derived from the marine autogenetic source. In the MZB, two depletion events occurred in TC and TOC storage from 1985 to 1987 and 2003 to 2006, which were coeval with the water impoundment in the Gezhouba and Three Gorges dams, respectively. The high-resolution records of the carbon storage rates and fluxes in the SYSA and MZB reflect the synchronous responses to human activities and provide an important reference for assessing the carbon sequestration capacity of the marginal seas of China. [ABSTRACT FROM AUTHOR]

Understanding global carbon cycle is critical to uncover the mechanisms of global warming and remediate its adverse effects on human activities. Organic carbon in marine sediments is an indispensable part of the global carbon reservoir in global carbon cycling. Evaluating such a reservoir calls for quantitative studies of marine carbon burial, which closely depend on quantifying total organic carbon and black carbon in marine sediment cores and subsequently on obtaining their high-resolution temporal sequences. However, the conventional methods for detecting the contents of total organic carbon or black carbon cannot resolve the following specific difficulties, i.e., (1) a very limited amount of each subsample versus the diverse analytical items, (2) a low and fluctuating recovery rate of total organic carbon or black carbon versus the reproducibility of carbon data, and (3) a large number of subsamples versus the rapid batch measurements. In this work, (i) adopting the customized disposable ceramic crucibles with the microporecontrolled ability, (ii) developing self-made or customized facilities for the procedures of acidification and chemothermal oxidization, and (iii) optimizing procedures and carbon-sulfur analyzer, we have built a novel Wang-Xu-Yuan method (the WXY method) for measuring the contents of total organic carbon or black carbon in marine sediment cores, which includes the procedures of pretreatment, weighing, acidification, chemothermal oxidation and quantification; and can fully meet the requirements of establishing their highresolution temporal sequences, whatever in the recovery, experimental efficiency, accuracy and reliability of the measurements, and homogeneity of samples. In particular, the usage of disposable ceramic crucibles leads to evidently simplify the experimental scenario, which further results in the very high recovery rates for total organic carbon and black carbon. This new technique may provide a significant support for revealing the mechanism of carbon burial and evaluating the capacity of marine carbon accumulation and sequestration. [ABSTRACT FROM AUTHOR]

Coastal seas, located between continents and the open ocean, are an important active carbon pool. The sedimentary total organic carbon (TOC) in these areas is a mixture of terrestrial and marine sources, and can be a powerful proxy for tracing natural processes and human activities. In this study, one fine-grained sediment core (DH5-1) from the inner shelf of the East China Sea was systematically analyzed for TOC and black carbon (BC) contents and TOC stable carbon isotope ratios (δ13C). By combining these data with 210Pb dating, an improved carbon correction model and a two end-member mixing model, we reconstructed century-scale high-resolution sequences of corrected TOC, terrestrial TOC and marine TOC contents and identified two carbon depletion events in the DH5-1 record. The two events, shown as two minima in the TOC profiles, correspond temporally to 1985-1987 AD and 2003-2006 AD, which exactly matches the water impoundment of the Gezhouba Dam and Three Gorges Dam, respectively. In addition, the variations in TOC contents and δ13C values before, during or after the minima demonstrate a relationship between the depletion events and water impoundment of the dams on the Changjiang River. The TOC reductions may represent synchronous responses of sedimentary TOC and resultant ecological effects on the inner shelf of the East China Sea to the water impoundment of the dams. These new TOC records reflect the interaction between natural and anthropogenic processes and, accordingly, provide a deep insight and important references for assessing marine ecological effects resulting from water impoundment of largescale dams. [ABSTRACT FROM AUTHOR]

Global carbon cycling is a significant factor that controls climate change. The centennial-scale variations in total organic carbon (TOC) contents and its sources in marginal sea sediments may reflect the influence of human activities on global climate change. In this study, two fine-grained sediment cores from the Yellow Sea Cold Water Mass of the South Yellow Sea were used to systematically determine TOC contents and stable carbon isotope ratios. These results were combined with previous data of black carbon and 210Pb dating from which we reconstructed the centennial-scale initial sequences of TOC, terrigenous TOC (TOCter) and marine autogenous TOC (TOCmar) after selecting suitable models to correct the measured TOC (TOCcor). These sequences showed that the TOCter decreased with time in the both cores while the TOCmar increased, particularly the rapid growth in core H43 since the late 1960s. According to the correlation between the Huanghe (Yellow) River discharge and the TOCcor, TOCter, or TOCmar, we found that the TOCter in the two cores mainly derived from the Huanghe River and was transported by it, and that higher Huanghe River discharge could strengthen the decomposition of TOCmar. The newly obtained initial TOC sequences provide important insights into the interaction between human activities and natural processes. [ABSTRACT FROM AUTHOR]

Black carbon (BC) has received increasing attention in the last 20 years because it is not only an absorbent of toxic pollutants but also a greenhouse substance, preserving fire-history records, and more importantly, acting as an indicator of biogeochemical cycles and global changes. By adopting an improved chemothermal oxidation method (WXY), this study reconstructed the century-scale high-resolution records of BC deposition from two fine-grained sediment cores collected from the Yellow Sea Cold Water Mass in the South Yellow Sea. The BC records were divided into five stages, which exhibited specific sequences with three BC peaks at approximately 1891, 1921, and 2007 AD, representing times at which the first heavy storms appeared just after the termination of long-term droughts. The significant correlation between the times of the BC peaks in the cores and heavy storms in the area of the Huanghe (Yellow) River demonstrated that BC peaks could result from markedly strengthened sedimentation due to surface runoff, which augmented the atmospheric deposition. Stable carbon isotope analysis indicated that the evident increase in carbon isotope ratios of BC in Stage 5 might have resulted from the input of weathered rock-derived graphitic carbon cardinally induced by the annual anthropogenic modulation of water-borne sediment in the Huanghe River since 2005 AD. Numerical calculations demonstrated that the input fraction of graphitic carbon was 22.97% for Stage 5, whereas no graphitic carbon entered during Stages 1 and 3. The obtained data provide new and important understanding of the source-sink history of BC in the Yellow Sea. [ABSTRACT FROM AUTHOR]

The dependence of starting materials and their initial grain sizes on the formation of gases (H, CH, CH and CH) during serpentinization was investigated by conducting hydrothermal experiments at 311°C and 3 kbar on olivine and peridotite with initial grain sizes ranging from <30 to 177 µm. Hydrocarbons (CH, CH and CH) were produced from reaction between dissolved CO in the starting fluids and H formed during serpentinization, which were analyzed by Gas Chromatography. It was found that olivine serpentinization produced much less H and CH compared with those after peridotite alteration, while their CH and CH were identical. For example, for olivine with initial grain sizes of <30 µm, the amounts of H and CH were 79.6 mmol/kg and 460 µmol/kg after 27 days, respectively. By contrast, the quantities of H and CH produced in experiment on peridotite with the same run duration were much larger, 119 mmol/kg and 1300 µmol/kg, respectively. This indicates that spinel and pyroxene in peridotite may increase the amounts of H and hydrocarbons, possibly due to the catalytic effect of aluminum released by spinel and pyroxene during serpentinization. Moreover, the production of H and hydrocarbons is negatively correlated with initial grain sizes of the starting material, with smaller amounts of H and hydrocarbons for larger initial grain sizes, indicating that the kinetics of serpentinization influences the formation of H and hydrocarbons, possibly because of the lack of catalytic minerals for the starting material with larger grain sizes. This study suggests that olivine cannot completely represent peridotite during serpentinization, and that H and hydrocarbons in hydrothermal fields near the mid-ocean ridge may be produced in a very long period of serpentinization or the presence of catalytic minerals due to large grain sizes of ultramafic rocks. [ABSTRACT FROM AUTHOR]

We developed a new magnetic nanovector to improve the efficiency and targeting of transgene therapy for oral squamous cell carcinoma (OSCC). Positively charged polymer PEI-modified FeO magnetic nanoparticles were tested as gene transfer vectors in the presence of a magnetic field. The FeO nanoparticles were prepared by a co-precipitation method and had good dispersibility in water. These nanoparticles modified by PEI were combined with negatively charged pACTERT-EGFP via electrostatic interaction. The transfection efficiency of the magnetic nano-gene vector with the magnetic field was determined by a fluorescence-inverted microscope and flow cytometry. The results showed significant improvement compared with the control group ( p < 0.05). The magnetic complexes also exhibited up to 6-times higher transfection efficiency compared with commonly used PEI or lipofectin. On the basis of these results, the antitumor effect with suicide gene therapy using pACTERT-TRAIL in vitro and vivo was evaluated. In vitro apoptosis was determined with the Annexin V-FITC Apoptosis Detection Kit. The results suggested that PEI-modified FeO nanoparticles could mediate the killing of Tca83 cells. Furthermore, treatment with pACTERT-TRAIL delivered by magnetic nanoparticles showed a significant cytostatic effect through the induction of apoptosis in a xenograft model. This indicates that magnetic nano-gene vectors could improve the transgene efficiency for Tca83 cells and could exhibit antitumor functions with the plasmid pACTERT-TRAIL. This may be a new way to treat OSCC. [ABSTRACT FROM AUTHOR]

Routine GC/MS analysis may apply to the volatilized Low-Molecular-Weight compounds in saturate and aromatic hydrocarbon fractions; thus, relative studies using this technique inevitably bring about some limitations on distribution of miscellaneous sulfur atom. In this article, Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) with high resolution is employed to investigate the distribution of organic sulfur compounds (OSCs) in the crude oil typically derived from the Eogene carbonate-evaporite sediments with further chemical compositional characterization in molecular level by miscellaneous atomic type, carbon number, and double bond equivalent (DBE). A variety of miscellaneous atomic types with S, S, S, OS, OS, OS, OS, NS, and NOS etc. (S1 means those OSCs with one sulfur atom in a molecule) were identified in OSCs in these oil samples. High levels of alkyl thioether series compounds with one ring structure were presented mainly in the crude oil in the Jianghan Basin whereas high amounts of benzothiophene, dibenzothiophene etc. compounds with higher values in DBE and carbon number range occurred in the sulfur-rich heavy oil in the Jinxian Sag. Although carbonate-evaporite sediments deposited in the saline lacustrine facies in the Eogene basin both occurred in the Jinxian Sag and Jianghan Basin, obviously, they possess different chemical diagenetic pathway of sulfur under various microbial reactions, leading to diverse distributional characteristics on biomarkers, OSCs, and even different hydrocarbon generation mechanism of immature crude oil. [ABSTRACT FROM AUTHOR]

Tissue engineering strategies often fail to regenerate bones because of inadequate vascularization, especially in the reconstruction of large segmental bone defects. Large volumes of vascular endothelial cells (ECs) that functionally interact with osteoblasts during osteogenesis are difficult to obtain. In this study, we simulated bone healing by co-culturing differentiated ECs and mesenchymal stem cells (MSCs) either on a culture plate or on a polylactide glycolic acid (PLGA) scaffold in vitro. We also evaluated the effect of osteogenesis in repairing rabbit mandible defects in vivo. In this study, MSCs were separated from rabbit as the seed cells. After passage, the MSCs were cultured in an EC-conditioned medium to differentiate into ECs. Immunohistochemical staining analysis with CD34 showed that the induced cells had the characteristics of ECs and MSC. The induced ECs were co-cultured in vitro, and the induction of MSCs to osteoblast served as the control. Alkaline phosphatase (ALP) and alizarin red (AZR) staining experiments were performed, and the Coomassie brilliant blue total protein and ALP activity were measured. The MSCs proliferated and differentiated into osteoblast-like cells through direct contact between the derived ECs and MSCs. The co-cultured cells were seeded on PLGA scaffold to repair 1 cm mandible defects in the rabbit. The effectiveness of the repairs was assessed through soft X-ray and histological analyses. The main findings indicated that MSCs survived well on the scaffold and that the scaffold is biocompatible and noncytotoxic. The results demonstrated that the co-cultured MSC-derived ECs improved MSC osteogenesis and promoted new bone formation. This study may serve as a basis for the use of in vitro co-culturing techniques as an improvisation to bone tissue engineering for the repair of large bone defects. [ABSTRACT FROM AUTHOR]

High abundant sulfur-containing steroids were identified and detected in saturate hydrocarbon fractions of heavy oil with a high sulfur content in the Jinxian Sag, Bohai Bay Basin, North China. These sulfur-containing steroids were structurally merged into the D-ring of steroid nucleus with thiophene ring and/or combined into the C-22 in the side-chain. Based on the previous reports of sulfur-containing steroids with methylthio-teroids and intra-molecular form, four formation mechanisms of sulfur-containing steroids and diagenetic pathway of steroids under S-rich conditions were proposed in this paper according to the double bond positions in the sterene compounds. Hydrogenation and sulfurization both occurred in the diagenetic processes of olefinic bond in the side-chain of steroids: abiogenic chemical hydrogenation of HS and HS leads to the formation of regular steranes; a successful sulfurization process leads to the formation of the side-chain sulfur-containing steroids whereas unsuccessful cyclization and/or sulfurization result in the generation of short-chain steranes. This kind of mechanism of hydrogenation/sulfurization of side-chain olefinic bond provides a potential genesis clue for the occurrence of high abundance of short-chain steranes (higher than the common regular steroids, phytane and n-alkanes) in S-rich heavy oils and source rocks in the Jinxian Sag, Bohai Bay Basin, North China. [ABSTRACT FROM AUTHOR]

Tight reservoirs are widely distributed, especially in coal measure strata. Identification of the densification mechanism of the tight sandstone reservoirs is critical in effectively exploring and exploiting tight gas/oil resources. In this study, the gas formation from type III organic matter in coal was kinetically modeled for the whole diagenetic stage, from the shallow buried biogas generation stage to the deep buried thermal gas generation stage. The results demonstrated that during hydrocarbon formation, quantities of non-hydrocarbon gases, such as CO, were generated. The proportion of CO is about 50%-70% of that of the C, which far exceeds the CO content (0-5%) in the natural gas in the sedimentary basins. Geological case study analysis showed that a considerable part of the 'lost' gaseous CO was converted into carbonate cement under favorable environments. Under the ideal conditions, the volume of the carbonate cement transformed from total CO generated by 1 m3 coal (Junggar Basin Jurassic, TOC 67%) can amount to 0.32 m. Obviously, this process plays a very important role in the formation of tight sandstone reservoirs in the coal measures. Our results also show that the kinetic generation processes of C and CO are asynchronous. There are two main stages of CO generation, one at the weak diagenetic stage and the other at the over-mature stage, which are different from large-scale multi-stage hydrocarbon gas generation. Therefore, we can understand the mechanism of tight gas charging by determining the filling time for a tight gas reservoir and the key period of CO generation. Further analysis and correlation studies of a specific region are of great significance for determining the mechanism and modeling gas charging in tight reservoirs. It should be noted that the formation of tight sandstone reservoirs is the combined result of complex organic-inorganic and water-rock-hydrocarbon interactions. The details of spatial and temporal distributions of the carbonate cement derived from the organic CO, which combines with metal ions (Ca/Mg/Fe) in the formation water, should be further investigated. [ABSTRACT FROM AUTHOR]

Crude oil cracking to gas is the key to determining the exploration potential and strategy for deep hydrocarbon resources. Identifying the factors that affect the threshold and potential of crude oil cracking to gas as well as other possible influencing factors will provide the scientific basis for deep hydrocarbon exploration. A comparison of pyrolysis simulation experiments of crude oil, hydrous crude oil, and various water media under a constant temperature (350°C) and pressure (50 MPa) shows that water plays a large role in crude oil cracking to gas. (1) When water is added, the gas yields increase significantly, including those of alkane gases and non-hydrocarbon gases: the yield of alkane gases increases 1.8-3 times; the yields of H and CO also increase significantly. This means that water takes part in the process of crude oil cracking to gas, and supplies hydrogen. Therefore, the presence of water will dramatically enhance the potential of crude oil cracking to gas. (2) Mg ions in the formation water promote the crude oil + water reaction to some extent and increase the total yield of alkane gases and the yields of both H and CO; more interestingly, the i-C/ n-C and i-C/ n-C ratios increase significantly. This indicates that Mg ions in formation water act as a catalyst, and a disproportionation reaction is involved in the crude oil + water reaction. This study helps us to understand the factors influencing crude oil cracked gas and to evaluate the hydrocarbon resources in deep sedimentary basins. [ABSTRACT FROM AUTHOR]

The growth, invasiveness, and metastasis of human cancers are not only determined by the cancer cells but also by their microenvironment. The purpose of this study was to extend our previous studies and to examine the cellular changes in tumor microenvironment (stroma) of esophageal squamous cell carcinomas (ESCCs). The proliferative activity, cellular components, and angiogenesis status in different compartments (non-tumor stroma, tumor stroma, and tumor periphery stroma) of ESCCs were evaluated by immunohistochemistry. The results revealed a hyperproliferative rate labeled by Ki-67 in stromal cells in tumor area as compared with that in stromal cells in non-tumor area, which resulted in the increased densities of myofibroblasts (labeled by smooth muscle actin (SMA)-alpha), lymphocytes (labeled by CD3), macrophages (labeled by CD68), and the activation of angiogenesis characterized by increased microvessel density (MVD) and the increased expression of the proangiogenic factors (vascular endothelial growth factor and interleukin 8) in the tumor stroma. Further analysis showed that the changes of stromal cell density were more significant in the area of periphery tumor stroma than that of stroma between tumor nests. Most cellular changes were significantly associated with lymph node involvement. Double immunohistochemistries with PCNA/CD3, PCNA/CD68, and PCNA/SMA-alpha revealed that these cells present in the ESCC tumor stroma had a proliferative capacity. The cells present in the tumor microenvironment of ESCCs were greatly activated, suggesting that microenvironmental components may be involved in the cancer growth and progression. [ABSTRACT FROM AUTHOR]

Temperature-programmed simulation experiments of saturated hydrocarbons with calcium sulfate and element sulfur were compared in this study. Based on the variation analysis of the yields and evolvement features of gaseous hydrocarbon (C1—C5) and inorganic gaseous CO2, H2 and H2S, the reaction mechanisms were analyzed and discussed. In the calcium sulfate-saturated hydrocarbon system, H2S was produced by a small quantity, which indicates this reaction belongs to the low-degreed thermal sulfate reduction (TSR) and is featured of self-pyrolysis. In the sulfur-saturated hydrocarbon system, the heated sulfur becomes sulfur radical, which has strong catalysis capability and can fasten the cracking of C—H bond in the alkyl group in the saturated hydrocarbons. As a result, the cracking of C—H bond leads to the yields enhancement of CO2 and H2, and at the same time, H2S was produced since the cracked hydrogen can be instantly combined with sulfur radical. Therefore, this reaction in the sulfur-hydrocarbon system belongs to the catalysis of sulfur radical. Furthermore, the promoted pyrolysis effects of C6+ hydrocarbons by sulfur radical in the low-temperature stage in the sulfur-hydrocarbon system, together with the consumption effects of gaseous hydrocarbon in the high-temperature stage in the calcium-hydrocarbon system, result in the crossed phenomenon of the gaseous hydrocarbon yields curves. [ABSTRACT FROM AUTHOR]

Kinetic experiments of gas generation for typical samples of marine gas precursors including low-maturity kerogen, residual kerogen and oil as well as dispersed liquid hydrocarbon (DLH) in source rocks were performed by closed system, and the evolution trends of molecular and isotopic compositions of natural gases from different precursors against the maturity ( R 0%) at laboratory conditions were analyzed. Several diagrams of gas origin were calibrated by using the experimental data. A diagram based on the ratio of normal and isomerous butane and pentane ( i/nC4 − i/nC5) was proposed and used to identify the origins of the typical marine natural gases in the Sichuan Basin and the Tarim Basin, China. And the maturities of natural gases were estimated by using the statistical relationships between the gaseous molecular carbon isotopic data and maturities (δ13C- R 0%) with different origins. The results indicate that the molecular and isotopic compositions of simulated gases from different precursors are different from each other. For example, the dryness index of the oil-cracking gas is the lowest; the dryness indices of gases from DLH and kerogen in closed system are almost the same; and the dryness index of gases from residual kerogen is extremely high, indicating that the kerogen gases are very dry; the contents of non-hydrocarbon gases in kerogen-cracking gases are far higher than those in oil-cracking and DLH-cracking gases. The molecular carbon isotopes of oil-cracking gases are the lightest, those of kerogen in closed system and GLH-cracking gases are the second lightest, and those of cracking gases from residual kerogen are the heaviest. The calibration results indicate that the diagrams of In(C1/C2)-In(C2/C3) and δ4 3C2-δ4 3C3-In(C2/C3) can discriminate primary and secondary cracking gases, but cannot be used to identify gas origin sources, while the diagram of i/nC4 − i/nC5 can differentiate the gases from different precursors. The application results of these diagrams show that gas mixtures extensively exist in China, which involved the gases from multiple precursors and those from different maturity stages. For example, marine gases in the Sichuan Basin involve the mixture of oil-cracking gases and high-over-maturated kerogen gases, while those in the Tarim Basin involve not only the mixture of gases from multiple precursors, but also those from different maturity gases and post-reservoir alternations such as oxidized degradation and gas intrusion processes. [ABSTRACT FROM AUTHOR]

The kinetic parameters of hydrocarbon generation from the marine carbonate source rocks were determined and calibrated through kinetic simulating experiment. The kinetic parameters of hydrocarbon generation then were extrapolated to geological condition by using the relative software. The result shows that gaseous hydrocarbons (C1, C2, C3, C4-5) were generated in condition of 150°C>T> 220°C(1.0%>R0 >3.0%). Light hydrocarbons (C6-13) and heavy hydrocarbons (C13+) were generated in condition of 100 °C >T<170 °C (0.5%0>1.5%). A quantitative reference to examine the natural evolution of hydrocarbon of marine carbonate source rocks can be established through the results. It also provides a new method for evaluating the highly mature marine carbonate source rock more reasonably. [ABSTRACT FROM AUTHOR]

A new method for the quantitative assessment of hydrocarbon generation potential from coals by means of the chemical reaction kinetics has been developed gradually over the recent years. In this paper, the kinetic parameters of hydrocarbon gas generation are determined by high temperature and pressure, and closed- system thermal simulation for Late Paleozoic coals in the Qinshui Basin and the kinetic characteristics and the histories of hydrocarbon gas generation were studied using the parameters obtained. Results show that during the longer period from the Triassic (T) to the Middle Jurassic (J2), the coal-derived methane yield increased more slowly under lower palaeogeotemperature in the Qinshui Basin; however, the shorter period from Late Jurassic to Early Cretaceous, the coal-derived methane yield increased more rapidly under higher palaeogeotemperature. The correlation between the thermal simulation and the factual data shows that C1/(C1+C2-4) coefficients computed by the histories of methane and C2-C4 hydrocarbon generation can provide evidence for the identification of the genesis of coal bed gas in the different areas of the Qinshui Basin. The kinetic simulating experiment of hydrocarbon generation for the peat considered as the original matter of coal formation was performed for the first time and the simulated results were compared with the characteristics of hydrocarbon generation from coals undergoing various palaeogeotemperature in the Qinshui Basin. The result indicates that the peat has a higher potential of hydrocarbon generation than that of coals. Therefore, the hydrocarbon generation results obtained from kinetic simulation for coal with higher maturation rank could not stand for their original hydrocarbon generation potential and thus would lead to an underestimation for coal-bed gas resource. The generative amount of coal-derived gas in the Qinshui Basin was predicted using kinetic simulation results for the peat and their maximum was estimated. The calculation shows that the generative amount of coal-derived gas from Taiyuan Formation and Shanxi Formation coal-beds in the Qinshui Basin is the highest in Yangcheng area, higher in Qinyuan area and the lowest in Huoshan area. Therefore, the conditions of coal-bed gas generation are the best in Yangcheng area, the second in Qinyuan area and not very good in Huoshan area. [ABSTRACT FROM AUTHOR]

Kinetics study of gaseous hydrocarbons generated from vitrinites based on pyrolysis of gold tube closed system shows that the activation energies of methane generated from telocollinite are higher than that from desmocollinite due to structure differences. But carbon isotope ratios of generated methane in pyrolysates of vitrinites at the same temperature points are similar. Carbon isotope ratio of methane may decrease in the early stage of gas generation and then increase in the later stage. But at higher temperature, Δ13C1 decreases slightly or almost keeps stable with increasing temperature. Since it is known that carbon isotope distillation is controlled by time, temperature and carbon isotope ratio of bulk organic matter, the character of side chains connected to macromolecule of vitrinite and distribution of activation energies have no obvious effect on carbon isotope fraction. Decreasing trend of Δ13C1 in the early stage may be caused by contagious structure of vitrinite or differences of activation energies between 12C-12C and 12C-13C are not strictly constant at different ranges of activation energy area. [ABSTRACT FROM AUTHOR]

By using the methods of hydrocarbon generation kinetics and carbon isotope kinetics, combined with geological background of natural gas pool formation, the generation and accumulation of natural gas from Yinan 2 gas pool was studied in Kuqa Depression of the Tarim Basin. Natural gas of Yinan 2 gas pool is mainly derived from Middle and Lower Jurassic coal-bearing source rocks, and generally belongs to long time-accumulated gas. It is suggested that Yinan 2 gas is chiefly accumulated in the last 5 Ma, its Ro ranges from 1.25% to 1.95%, and the loss rate of natural gas is about 25%–30%. This work not only complements and reduces the deficiency of formation model of natural gas pools which traditionally depends on the matching relationships between source rock, reservoir, cap rock, and trap, but also is a useful reference in the study of other gas pools. [ABSTRACT FROM AUTHOR]

Sulfur plays an important role in the generation and evolution of hydrocarbon from organic matter. Here, a pyrolysis experiment in closed system was performed on Maoming oil shales kerogen (Type I), Maoming oil shales kerogen added with sulfur ether and Maoming oil shales kerogen added with sulphur. The results suggest that the existence of sulfur can result in: (i) higher yield of hydro-carbons generated from the kerogen; (ii) decrease of the temperature for the maximum generation of heavy hydro-carbons (the C15+ fraction) by 20°C; (iii) decrease of the temperature for the maximum generation of the aromatics fraction by 40°C, and (iv) acceleration of the aromatization process. The pyrolysates from kerogen added with sulfur are similar to the heating products of the sulfur-rich kerogen as reported in the literatures. It seems that the sulfur catalysis is also an important factor that can make the sulfur-rich kerogen generate low-mature oil at the earlier diagenesis stage, except for the weakness of the C-S and S-S bonds. [ABSTRACT FROM AUTHOR]

Secondary variation of reservoir is a hot problem in petroleum geochemistry field. Several kinds of secondary variations have taken place after the formation of bituminous sandstones in the Tarim Basin including biodegradation, washing, dissipation and secondary thermal stress. Biodegraded bituminous sandstones were used in the experiment. Pyrolysis experiment has been performed in a closed system, simulating secondary thermal stress with continual burial of Silurian bituminous sandstones which may cause the changes in molecular compositions, carbon isotope and physical properties of bituminous sandstones. The results are as follows: (i) Gases are mainly product during the experiment and carbon isotope of gas is lighter. (ii) Yield of C6+ hydrocarbon is relative smaller, and yielded oil is mainly light oil. (iii) Chromatogram character of biodegraded oil-sand is similar to that of saturated hydrocarbon in extracts from present-day bituminous sandstones. (iv) Porosity of bituminous sandstones gradually increases with increasing temperature. Fluorescence color of bituminous sandstones gradually become darker. Reflected light color of bitumen in bituminous sandstones becomes darker with increasing temperature and reflectivity of bitumen increases with increase in temperature. It is speculated that secondary thermal stress has great effect on molecular composition and structure of bituminous sandstones. [ABSTRACT FROM AUTHOR]

Kinetic parameters were characterized for the formation of the C1–C5 hydrocarbons generating from Taiyuan and Shanxi coal in the Upper Paleozoic of the Ordos Basin, through pressurized simulation experiment designed for the kinetic study of hydrocarbon generation. Based on the palaeogeothermal evolution of the Upper Paleozoic strata in the Ordos Basin, the formation and evolution of gas from Taiyuan and Shanxi coal in the eastern and central regions of the Ordos Basin were reproduced, and it is suggested that large scale secondary hydrocarbon generation does not exist during the uplifting and cooling process of the basin at the end of Early Cretaceous. Some of the factors affecting the behavior of the coal-generated gas were also discussed, and it is emphasized that the most fundamental element determining the hydrocarbon generation behavior is the characteristic of the precursor hydrocarbon-source rock. [ABSTRACT FROM AUTHOR]

Investigates the possible involvement of transformation in the mineralization of Baiguoyuan silver-vanadium deposit in Hubei Province, China. Evidence for transformation; Geological background of transformation; Mechanism of transformation.

Applies the kinetics method in assessing determining whether methane in the strata was generated in situ mainly by thermal degradation of local organic matter from the Green River shale. Assessment whether kerogen could produce methane of the required concentration; Results suggesting that from the view of hydrocarbon generation, methane in the seam should be from thermal degradation of local kerogen.

Presents a study on light hydrocarbons in mineral inclusions. Detailed information on this study; Experimental procedures used; Results of this study.

A heavy-media separation has brcu carried out to study the partition of germanium in various macetals ol mineralized lignites in Lincang superlarge gerrtlilnium deposit in Yunniln, China. The result shows that Ge stays predominantly in huminites, especially in corpohuminitrs (86.04–89.16%), next in light macerals and minerals (3.20%–8.33% and 1.71%–10.27%, respectively). In addition, the EPMA and PIXE analyses suggest that no germanium minerals have been detected and Ge is well distributed in the whole mineralized lignite, bonding to O, C and H of coaly organic matter of mineralized lignites. [ABSTRACT FROM AUTHOR]