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Organic‐rich shale in saline lacustrine basins holds significant importance as a source rock for conventional hydrocarbon exploration and has emerged as a prominent target for unconventional hydrocarbon exploration and development in recent years. Based on saline lacustrine basins, this paper provides a summary of the organic matter enrichment mechanisms in saline lacustrine basins, considering sedimentary characteristics, biological activities, factors for the organic matter enrichment and consumption, and hydrocarbon generation. The implications for these factors are discussed in relation to the distribution prediction of high‐quality lacustrine shale district settings and the exploration and development of shale oil. Saline lacustrine basins undergo distinct evolutionary stages, each corresponding to different sedimentary stages involving carbonate minerals, sulphate minerals, and alkaline minerals. Moreover, these basins exhibit diverse biological types and experience extensive biological activities. The prosperity of organisms and the accumulation of sedimentary organic matter are ensured by halophilic organisms. Organic matter enrichment in saline lacustrine basins is influenced by two main aspects: the primary productivity of organic matter, which is promoted by the proliferation of halophilic organisms, and the efficient preservation of organic matter facilitated by the strong reducing environment resulting from promoted water salinity stratification. The organic matter consumption in saline lacustrine basins involves bacterial sulphate reduction (BSR) in the early stages, thermochemical sulphate reduction (TSR) in the late stages, and dilution of salt minerals with higher depositional rates. of the presence of salt beds and saline minerals positively influences hydrocarbon generation and expulsion in organic‐rich shale within saline lacustrine deposition. Consequently, continental saline lacustrine basins in China offer favourable conditions for the formation of organic‐rich shale and present broad prospects for the exploration of shale oil and gas resources. [ABSTRACT FROM AUTHOR]

Laminated shales are widely developed in the Dongying Sag and have attracted much attention as an oil reservoir. Macroscopically, these shales generally have multi-scale cyclicity, which is closely related to the development of laminae. Therefore, analyzing the origin of their cyclicity is helpful to understanding the formation mechanism of laminated shales and the vertical heterogeneity of shale reservoirs, which are of great significance for continental shale oil exploration and development. In this study, a gamma ray (GR) logging series, high-resolution elemental geochemical data, high-resolution core scanning photos and grayscale data, and mineralogical data were used to characterize the cyclicity of shale at different scales, and their relationship with different astronomical cycles was discussed. The results show that the Es3L and Es4U shale in the Dongying Sag has cyclicity from the meter-scale to the ten-meter scale and then to the hundred-meter scale, which is mainly manifested by periodic changes in organic matter abundance, mineral composition, element abundance, and grayscale. These cycles of different scales coincide with different astronomical periods. Specifically, the hundred-meter scale cyclicity is mainly controlled by the very long orbital period; the ten-meter scale cyclicity is mainly related to the eccentricity cycle; while the precession period is the main driver of the meter-scale cyclicity. Finally, we propose a simplified model for illustrating the formation of rhythmic organic-rich shale. This study is helpful to understanding the origin of continental organic-rich shale and predicting shale reservoir properties. [ABSTRACT FROM AUTHOR]

The successful development of shale oil in China has claimed that laminated shale is a favorable lithofacies for the effective extraction of petroleum. Clarifying the role of laminae in shale oil generation, migration, storage, and enrichment is urgent and important. Starting from the describing and classifying of the lamina, the common methods and terms used to delineate lamina types are briefly summarized. The results of different schemes are often mutually inclusive, which prompted scholars to work towards a unified division scheme. The influencing factors of oil retention in shale systems, including organic matter (OM) type, total organic carbon (TOC) content, OM maturity, mineral composition, pore structure, and preservation conditions, are systematically discussed. Subsequently, comparative work on source rock quality, reservoir properties, and hydrocarbon expulsion efficiency of shales with different laminar structures is carried out. The comparison results of shale with different rock structures reveal that the laminated shale has a high expulsion efficiency. However, the strong oil generation capacity and superior storage space of laminated shale synergistically control the considerable amount of retained oil in the shale system. Especially the oil mobility of laminated shale is also considered because of great pore size and pore connectivity. The fine evaluation of laminar structure and prediction of laminar distribution has great significance for the selection of shale oil "sweet spot area" or "sweet spot interval". [ABSTRACT FROM AUTHOR]

The laminar structure of shale system has an important influence on the evaluation of hydrocarbon source rock quality, reservoir quality, and engineering quality, and it is receiving increasing attention. A systematic study of the lamina structure is not only of great scientific significance but also of vital practical importance for shale oil production. In this paper, the identification and description classification of shale laminae are first reviewed. Multiple scales and types indicate that a combination of different probe techniques is the basis for an accurate evaluation of shale laminar characteristics. The influence of laminae on shale reservoir, oil-bearing, mobility, and fracability properties is discussed systematically. A comparative analysis shows that shale systems with well-developed lamination facilitate the development of bedding fractures, thus improving the shale storage space. The average pore size and pore connectivity are also enhanced. These factors synergistically control the superior retention and flow capacity of shale oil in laminated shales. In such conditions, the high production of shale oil wells can still be achieved even if complex networks of fracturing cracks are difficult to form in shale systems with well-developed lamination. This work is helpful to reveal the enrichment mechanism of shale oil and clarify the high-yield law of hydrocarbons, so as to guide the selection of sweet spots. [ABSTRACT FROM AUTHOR]

In the present work, we report the exploration of integrated photoanode based on SiC nanohole arrays with a rationally designed amorphous carbon nanolayer. The SiC nanoarrays are fabricated via anodic oxidation, and the carbon outlayers are introduced by chemical vapor deposition (CVD) process, respectively. In such case, the active materials of carbon outlayer coated SiC nanoarrays (SiC@C) and current collector of the unetched SiC wafer are established into a whole structure without interfaces, thus favoring the formation of integrated photoanode. It is verified that the coated carbon nanolayer acts as an efficient hole storage layer, which effectively drives the separation of photogenerated carriers. Consequently, the as-fabricated SiC@C photoanode exhibits excellent photoelectrochemical (PEC) water splitting properties with a high solar-to-hydrogen efficiency of 2.67%. Moreover, it delivers an ultralow onset potential of −0.049 V (vs. RHE) and a high photocurrent density of 5.0 m A/cm2 (1.23 V vs. RHE), superior to those of intrinsic SiC counterparts and most SiC nanostructures ever reported, implying their promising applications in the field of solar energy conversion. We reported the integrated photoanode based on self-supported SiC nanohole arrays with an amorphous carbon nanolayer as hole storage layer, which exhibits promoted photoelectrochemical water splitting performance with an ultralow onset potential (−0.049 V vs. RHE) and high photocurrent density (5.0 m A/cm2 vs. RHE 1.23 V). [Display omitted] • The integrated photoanode based on self-supported SiC nanohole arrays with an amorphous carbon nanolayer were fabricated. • The carbon nanolayer acts as efficient holes storage layer that drives the separation of photogenerated carriers. • The active materials and current collector of the photoanode are established into a whole structure without interfaces. • The photoanode exhibits ultralow onset potential (−0.049 V vs. RHE) and high photocurrent density (5.0 m A/cm2 vs. RHE 1.23 V). [ABSTRACT FROM AUTHOR]

Many sets of Paleozoic marine organic-rich shale strata have developed in South China. However, the exploration and development results of these shale formations are quite different. Based on the data of core experiment analysis, drilling, fracturing test of typical wells, the reservoir differences and controlling factors of four sets of typical marine organic-rich shale in southern China are investigated. The four sets of shale have obvious differences in reservoir characteristics. Ordovician–Silurian shale mainly develops siliceous shale, mixed shale and argillaceous shale, with large pore diameter, high porosity, moderate thermal maturity, large pore volume and specific surface area. Cambrian shale mainly develops siliceous shale and mixed shale, with small pore diameter, low porosity, high thermal maturity and smaller pore volume and specific surface area than Ordovician–Silurian shale. Devonian–Carboniferous shale has similar mineral composition to Ordovician–Silurian shale, with small pore diameter, low porosity, moderate thermal maturity and similar pore volume and specific surface area to that of Cambrian shale. Permian shale has very complex mineral composition, with large pore diameter, low to medium thermal maturity and small specific surface area. Mineral composition, thermal maturity and tectonic preservation conditions are the main factors controlling shale reservoir development. Siliceous minerals in Cambrian shale and Ordovician–Silurian shale are mainly of biological origin, which make the support capacity better than Devonian–Carboniferous shale and Permian shale (siliceous minerals are mainly of terrigenous origin and biological origin). Thermal maturity of Ordovician–Silurian shale and Devonian–Carboniferous shale is moderate, with a large number of organic pores developed. Thermal maturity of Cambrian shale and Permian shale is respectively too high and too low, the development of organic pores is significantly weaker than the two sets of shale above. There are obvious differences in tectonic preservation conditions inside and outside the Sichuan Basin. Shale reservoirs inside the Sichuan Basin are characterized by overpressure due to stable tectonic activities, while shale reservoirs outside the Sichuan Basin are generally normal–pressure. Four sets of marine shale in South China all have certain resource potentials, but the exploration and development of shale gas is still constrained by complicated geological conditions, single economic shale formation, high exploration and development costs and other aspects. It is necessary for further research on shale gas accumulation theory, exploration and development technology and related policies to promote the development of China's shale gas industry. [ABSTRACT FROM AUTHOR]

Constructing core/shell nanoarrays with optimal structure and composition can maximize solar light utilization. In the present work, a distinct regular array of SiC/TiO2 core/shell nanoarray photoanodes with improved charge separation is successfully achieved through two sequential steps of electrochemical etching and atomic layer deposition. The suitable band offset between SiC and TiO2 results in forming a type-II heterojunction at the SiC/TiO2 interface, which efficiently promotes electron–hole separation. Under simulated sunlight illumination (100 mW/cm2), the SiC/TiO2 nanoarray composite photoanode exhibits a significantly improved photocurrent of 3.62 mA/cm2 at 1.4 V versus Ag/AgCl, which demonstrates significantly increased photoelectrochemical (PEC) activity compared to the intrinsic SiC photoanode. The significant enhancement of PEC behaviors is mainly assigned to the improved electron–hole separation at the surface of the junction, combined with the synergistic effect of the highly oriented nanochannel array configuration, single-crystal character of the etched entire SiC nanoarray film, as well as the incorporation of N dopants. We explored an N-doped 4H-SiC/TiO2 core–shell heterojunction nanochannel array photoanode for photoelectrochemical water splitting, which presents a high photocurrent density of ~ 3.62 mA/cm2 (1.4 V vs. Ag/AgCl). [ABSTRACT FROM AUTHOR]

Many sets of Paleozoic marine organic-rich shale strata are developed in southern China. However, the exploration and development degree of these strata are different. Cambrian shale and Ordovician-Silurian shale are two horizons with high degree of exploration, while Devonian shale and Carboniferous shale exploration is deficient. Based on XRD, FE-SEM, and gas adsorption experiment, pore development characteristics and controlling factors of Devonian and Carboniferous shale are investigated. There are mainly four lithofacies in Devonian and Carboniferous shale: mixed shale (M), carbonate/siliceous mixed shale (M-1), argillaceous/siliceous mixed shale (M-2), and argillaceous-rich siliceous shale (S-3). Reservoir characteristics of both two sets of shale strata are quite different. The averages of porosity, pore volume, and specific surface area of Devonian shale are 3.81 % , 9.7 × 10 − 3 cm3/g and 11.8 m2/g, while those of Carboniferous shale are 3.57%, 17.3 × 10 − 3 cm3/g and 19.8 m2/g. Thermal evolution (Ro) and tectonic preservation conditions are the main factors affecting the pore development. Carboniferous shale (Ro ≈ 2 %) is in the stage of producing a large number of organic pores. Devonian shale (Ro ≈ 3.5 %) is having difficulty preserving organic pores due to high thermal evolution. Meanwhile, Devonian shale (well GTD1) is strongly affected by tectonic movement; tectonic fractures and calcite veins are developed. Carboniferous shale (well GRY1) is in relatively stable area; tectonic fractures are not developed. Under the influence of compaction, the pore volume and specific surface area of Carboniferous shale are 78.3% and 67.8% higher than those of Devonian shale, respectively. This research can provide reference for clarifying shale pore development and evolution mechanism and similar shale gas exploration both in study area and around the world. [ABSTRACT FROM AUTHOR]

Organic-rich lacustrine shales are widely developed in China, and they have long been simply regarded as homogeneous source rocks, which restricts the understanding of intrasource oil accumulation. At present, the study of the LXF (Lower Member of the Xingouzui Formation) in the Jianghan Basin as an unconventional oil reservoir is still in its infancy, and the hydrocarbon accumulation mechanism is still unclear. Geochemical and mineralogical studies were carried out on a suite of samples from the 100-m-thick sequence, i.e., LXF II Oil Bed, by using XRD, SEM, MICP, and Rock-Eval pyrolysis. The results show that the II Oil Bed is rich in carbonate and poor in clay, so it shows a good fracturing tendency. The high degree of heterogeneity in mineral composition leads to frequent interbedding of different lithofacies. In the II Oil Bed, intercrystalline pores, interparticle pores, and intraparticle pores are developed, and micro-fractures are often observed. However, the main pore types, pore size distribution, and connectivity are quite different among lithofacies, and the carbonate-rich lithofacies have better reservoir capacity. The OM (organic matter) abundance of the II Oil Bed varies greatly and generally ranges from fair to very good. Coupled with its early-mature to mature Type II OM, it is considered to have the characteristics required for oil generation. Comprehensive analysis shows that the II Oil Bed has good shale oil exploration prospects, and the enrichment of shale oil in the sequence is the result of multiple factors matching. Firstly, high organic matter abundance is the material basis for shale oil enrichment. Secondly, thermal maturity is a prerequisite, and the difference in burial depth leads to the differential enrichment of shale oil in different areas. Thirdly, pores and micro-fractures developed in shale not only provide space for hydrocarbon storage, but also form a flow-path network. Finally, multi-scale intrasource migrations are key processes ranging from the scale of lithofacies to the intervals, which further results in the differential shale oil enrichment in different lithofacies and intervals. Considering the hydrocarbon generation capacity and reservoir quality, the prospective depth for shale oil exploration in the study area is >1350 m. The findings of this study can help in the better-understanding of the shale oil enrichment mechanism, and the optimization of future exploration strategies. [ABSTRACT FROM AUTHOR]

Malignant pleural mesothelioma (MPM) is a type of cancer originating from the pleura with high aggressiveness and poor prognosis. A timely diagnosis is crucial to improve its prognosis. Laboratory biomarkers have significant advantages of reduced invasiveness, low cost, and are observer‐independent, and therefore represent a promising diagnostic tool for MPM. MicroRNA is a family of non‐coding RNA that regulates gene expression at the post‐transcriptional level. Accumulated studies showed that microRNA, either in tissue, circulating, and body fluid, has potential diagnostic value for various disorders. Here, we reviewed the diagnostic value of microRNA for MPM. [ABSTRACT FROM AUTHOR]

The interactions between clay minerals and organic matter, specifically adsorption, are widely recognized as a crucial mechanism for promoting the preservation of organic matter within sedimentary environments. This paper discusses the genesis and adsorption of clay minerals, especially their influence on the process of organic matter enrichment in sedimentary environments. The composition of clay minerals found in sediments serves as an indicator of both the climatic and lithological characteristics of the provenance area. Smectite formation is favored in mafic provenance, while the coexistence of illite and chlorite suggests cold and arid conditions. Additionally, an abundance of kaolinite indicates intense chemical weathering of the provenance area. The physical and chemical properties of clay minerals and organic matter significantly influence adsorption. Smectite is thought to adsorb more organic matter due to its greater surface area. Selective adsorption of high molecular weight, aromatic, and aliphatic compounds dissolved organic matter onto mineral surfaces may have played a role in kerogen formation. Moreover, the preservation of organic matter via clay mineral adsorption is intricately linked to the sedimentary environment. Disparities in nutrient elements during the clay minerals synsedimentary period can impact biological productivity. Furthermore, the pH and solution metal ions of the water column influence the quantity and type of organic matter adsorbed. The contribution of adsorption to organic matter preservation is influenced by redox conditions, and this contribution can be observed through density separations. Additionally, we present several recommendations for future research. Firstly, diagenesis alters the clay mineral assemblage in sedimentary rocks. However, it may be possible to reconstruct the clay mineral assemblage based on morphological, mineralogical, and chemical composition characteristics. Secondly, studies have indicated that clay minerals can facilitate the precipitation of carbonate minerals, providing insights into the formation of abiotic carbonate minerals. Finally, the practical applications of clay minerals in shale oil and gas exploration are underscored, such as their ability to predict sweet-spot areas and control reservoir properties. [ABSTRACT FROM AUTHOR]

Both the shelf-edge trajectories and slope morphology are indicative of deep-water sedimentation, but previous studies are relatively independent from each other in the two dimensions. An integrated investigation can enhance the understanding of deep-water sedimentary systems and enrich reservoir prediction methods. Based on the bathymetry data and seismic data published, this study identified ten slope areas at the continental margin of East Africa and classified the clinoforms into three types: concave-up, sigmoidal and planar. Combined with the distribution of main modern rivers in East Africa, nine modern source-to-sink systems were identified and the catchment area is positively correlated with the size of the shelf-edge delta. It is found that the slope morphology of East Africa is closely related to the geological setting, sediment supply and sediment transport pathway in submarine canyon of passive continental margin. When the sediment supply is stable, the concave-up slopes are dominated by the river-associated and shelf-incising canyons and the sigmoidal slopes are determined by the headless canyons. There exists a strong coupling relationship between the shelf-edge trajectories and slope morphology. In general, concave-up slopes correspond to descending trend, flat and low-angle ascending trend shelf-edge trajectories and high-quality reservoirs developed on the basin floor under the influence of river-associated and shelf-incising canyons which have bright prospects for oil and gas exploration. Additionally, sigmoidal slopes usually correspond to descending trend, flat and low-angle ascending trend shelf-edge trajectories at times of relative sea-level fall and the reservoirs mostly developed on the upper slope under the influence of headless canyons. Moreover, the planar slopes correspond to high-angle ascending trend trajectories which are hardly potential for exploration. The coupling model built in this study will provide an insight for oil and gas exploration in deep-water areas with limited data and low exploration degree. [ABSTRACT FROM AUTHOR]

This study investigated the effects of microfabric and laminae on the pore structure and gas transport pathways of the Silurian Longmaxi shales from Sichuan Basin. 23 shale samples with varied lithofacies were comprehensively investigated by mineralogy, organic geochemistry, pycnometry, and low-pressure nitrogen adsorption analysis. The fabric and laminae of these samples were identified using petrographic microscope and scanning electron microscopy. Permeabilities were measured using the nonsteady-state method on both perpendicular and parallel to bedding shales. The effective pore diameter controlling gas transport was estimated from gas slippage factors obtained in permeability measurements. These values were also compared to those calculated using the Winland equation. Siliceous shales studied are faintly laminated to nonlaminated and have larger porosity and specific surface area. Argillaceous/siliceous mixed shales are well laminated, whereas argillaceous shales contain many oriented clay flakes along the lamination. Both porosity and surface area are positively correlated with TOC content. Unlike most conventional reservoirs, there is a negative correlation between porosity and permeability values of the samples studied. Permeabilities parallel to bedding, ranging from 0.4 to 76.6 μD, are in control of the oriented clay flakes and silty microlaminae. Permeability anisotropy values of the shales vary between 1.3 and 49.8. Samples rich in oriented clay flakes and microlaminated fabric have relatively larger permeability and permeability anisotropy values. The effective transport pore diameters derived from gas slippage measurements are slightly lower than those calculated from the Winland equation. However, both methods have shown that the effective transport pore diameters of argillaceous shales (averaging 552 nm) are significantly higher than siliceous shales (averaging 198 nm), which underlines the control of microfabric, rather than porosity, on gas transport pathways of the shales studied. [ABSTRACT FROM AUTHOR]

Domestic yaks are the most important livestock species on the Qinghai-Tibetan Plateau. Adult female yaks normally breed in warm season and enter anestrous in cold season. Currently, how the ovarian activity is regulated at the molecular level remains to be determined. This study was conducted to investigate follicular development and gene expression patterns of yak ovarian tissues in the warm and cold seasons. Dynamics of follicular development was evaluated based on histological analyses and global gene expression was examined by using RNA-sequencing (RNA-seq) technology. Firstly, we found that follicle development of yak cows in cold season was different from that in warm season. Interestingly, ovaries collected from yaks in cold season contained a significant higher number of antral follicles and some of these follicles showed signs of polycystic structure, indicating abnormal granulosa cell function. RNA-seq analyses of ovarian tissues from non-pregnant adult yaks in cold and warm season revealed that a list of 320 transcripts were differentially expressed, specifically, 79 were up-regulated and 241 were down-regulated in the ovaries from yaks during the cold season. Further analysis demonstrated that transcripts associated with estrogen secretion and metabolism signaling pathway were altered, including FST , CYP1A1 , PIK3R1 and PIK3R2. This study showed histological features of follicle development and revealed candidate genes that may have important roles in regulating ovarian activities in the yak seasonal reproduction. • Dynamics of ovarian follicle development of yak cows in cold season was different from that in warm season. • Yak ovaries in cold season contained a higher number of antral follicles that showed signs of polycystic structure. • RNA-seq analysis highlighted potential roles of estrogen signaling in seasonal regulation of ovarian activities in yaks. [ABSTRACT FROM AUTHOR]

In the design and development of small-caliber artificial blood vessels, endothelialization is a key issue, but it is not well understood at present. Some studies have used vascular endothelial growth factor (VEGF) sustained-release methods to promote endothelial cell proliferation. However, this method is not ideal. This study has used drugs to induce endothelial cells to produce VEGF. This method in turn functions to promote cell proliferation and promote the endothelialization of artificial blood vessels. This study aimed to investigate the effect of the antiplatelet drug tirofiban on endothelial cell proliferation in vitro. In this study, human umbilical vein endothelial cells (HUVECs) were used to determine the effect of tirofiban-stimulated cell proliferation. Analysis of cell proliferation, assayed by the Cell Counting Kit–8 assay, showed that the number of cells was increasingly higher than in the absence of tirofiban. It was also observed that heparin enhanced the tirofiban effect. The cell VEGF expression at different time points after tirofiban addition was detected by western blot analysis. The absorbance values of the experimental (1 μg/mL tirofiban) and the control groups (0 tirofiban) were 1.74 (SD, 0.03) and 1.51 (SD, 0.07) (P <.001), respectively, after 4 days of culture under the same conditions. The amount of VEGF produced by HUVECs gradually increased after treatment with tirofiban, reached a peak at 2 hours, and was 1.3-fold greater than the control group (P =.034). Compared with the tirofiban-only group, the absorbance value of the tirofiban and 10 μg/mL of heparin group was significantly increased (P <.001). Tirofiban promoted the proliferation of HUVECs by promoting the synthesis of VEGF in HUVECs. Heparin enhanced tirofiban activity in promoting HUVEC proliferation. • Tirofiban promoted the proliferation of human umbilical vein endothelial cells (HUVECs) by promoting the synthesis of vascular endothelial growth factor in HUVECs. • Heparin enhanced tirofiban activity in promoting HUVEC proliferation. • Tirofiban may have certain value in the development of small-caliber artificial blood vessels. [ABSTRACT FROM AUTHOR]

Open in new tab Download slide Open in new tab Download slide OBJECTIVES To study the perioperative outcomes and long-term survival rates in patients undergoing thoracic endovascular aortic repair (TEVAR) for uncomplicated type B dissection. METHODS A total of 751 patients with uncomplicated type B dissection who underwent TEVAR at our centre between May 2001 and December 2013 were retrospectively reviewed. The mean age of all patients (619 males and 132 females) was 52.8 ± 10.9 years. The follow-up period ranged from 1 to 170 months (median 70 months). RESULTS Five patients died during the perioperative period (mortality rate 0.7%). Four patients (0.5%) developed retrograde type A dissection. Two patients (0.3%) developed paraplegia and 1 patient developed incomplete paralysis (0.1%). There were no postoperative cerebral infarctions. The 5- and 10-year survival rates were 96.5% [95% confidence interval (CI) 95.0–98.0%] and 83.0% (95% CI 77.9–88.4%), respectively. The 5- and 10-year reintervention rates were 4.6% (95% CI 3.0–6.2%) and 7.9% (95% CI 5.3–10.5%), respectively. CONCLUSIONS Although the application of TEVAR for patients with uncomplicated dissection is still under debate, many patients who have undergone TEVAR have benefitted substantially from the treatment. Our data showed that TEVAR had low mortality and complication rates both in the short- and long-term follow-up periods. TEVAR may be considered as a first choice for patients with uncomplicated type B dissection. [ABSTRACT FROM AUTHOR]

The petrophysical characteristics of unconventional reservoirs have significant impacts on hydrocarbon storage and transport. In this study, 26 shale samples with various lithofacies from Lower Silurian Longmaxi shales in the Jiaoshiba area of Sichuan Basin are investigated. The pore network (morphology, porosity, and pore structure parameters) is comprehensively characterized using scanning electron microscopy, helium pycnometry, and low-pressure gas adsorption techniques. Permeability coefficients are derived from pulse-decay measurements on parallel to bedding samples. Geological controls on the pore shape, porosity, pore size, pore size distribution, and permeability of the shales are analyzed, and quantitative relationships with which to estimate the permeabilities and pore-throat apertures controlling gas flow are developed. Three general lithofacies are summarized in view of their mineralogy: siliceous, argillaceous/siliceous mixed, and argillaceous shales. Pore structure parameters (porosity, specific surface area, and pore volume) show positive correlations with total organic carbon (TOC) content. Organic matter-hosted pores contribute to approximate 67% of the porosity of siliceous shales, while inorganic matter contributes to 55% of the porosity of argillaceous shales. Klinkenberg-corrected permeabilities range between 0.01 and 46.4 μD, and are controlled by the alignment of clay flakes. Negative relationships exist between TOC content, porosity, and permeability values. Siliceous shales generally have the lowest permeabilities, whereas the argillaceous shales with developed oriented clay flakes have relatively high permeabilities. The seepage-pore apertures, estimated using the Winland correlation, range from 9 to 476 nm. These values are much higher than those obtained from nitrogen adsorption analysis (adsorption-pore apertures). A power correlation exists between seepage-pore apertures and total clay minerals content of shales studied. A fracture model (sheet) is used to predict absolute permeability based on seepage-pore apertures. The predictions are reasonable, and justify the application of the sheet model and seepage-pore apertures. The siliceous shales are featured by a high TOC content, large porosity and specific surface area, and low permeability, which are favorable to gas preservation. • Petrophysical characteristics of Longmaxi shales are documented. • Geological controls on pore structure and permeability of shales are investigated. • Seepage-pore aperture controlling gas flow is calculated. • A new method for estimating permeability using seepage-pore aperture is proposed. [ABSTRACT FROM AUTHOR]

The in-situ stress state of the eastern margin of the Sichuan Basin, where there is a complicated fault zone, is poorly understood. This study offers vital insights into the in-situ stress state based on information from 17 wellbores in the Wufeng-Longmaxi Shale near the eastern boundary fault (i.e., the Qiyueshan Fault) of the Sichuan Basin, China. Drilling-induced tensile fractures and borehole breakouts revealed a decrease in the angle between the S Hmax (maximum horizontal stress) orientation and fault strike when the wellbores are close to the damage zone of the Qiyueshan Fault. This stress rotation may be caused by the lateral contrast in the Poisson's ratio between the country rock and damage zone of the Qiyueshan Fault. A high angle between the S Hmax orientation and fault strike also appeared in the individual fault blocks of the Qiyueshan Fault as a result of local stress concentration. The higher magnitudes of horizontal stresses indicate stronger lateral compression in the Qiyueshan Fault Zone. Owing to the lateral compression of a "sandwich" consisting of a high-E (Young's modulus) roof and low-E shale intervals, natural fractures mainly appeared in the low-E shale intervals when the wellbore was close to the fault damage zone. The low fracture intensity in the low-E shale intervals of the wellbores located at the boundaries of the stress concentration blocks may be associated with an extensional stepover process. • Spatial variations in stress orientation and magnitude around the fault zone. • Lateral mechanical contrast decreases the angle between S Hmax and fault strike. • Stress concentration complicates S Hmax orientations in certain fault blocks. • Vertical mechanical contrast affects the natural fracture intensity of shale. [ABSTRACT FROM AUTHOR]

Pore-fracture structure of shales is important to shale gas resource potential evaluation, exploration and development. However, investigations about the pore-fracture structure of shales were mainly focused on nano-submicron pores, while the contribution of micrometer-scaled pores and micro-fractures to pore system of shale reservoirs lack sufficient attention. Here, using a combination of field-emission scanning electronic microscopy (FE-SEM), gas adsorption (N 2 and CO 2) and CT scanning (Nano-CT and Micro-CT), the Longmaxi shale cored from JYA well, in the Fuling area, was selected to comprehensively evaluate the characteristics of the pore-fracture structure at different scales. The results show that there are diverse types of pores in the organic-rich shale, mainly consisted of organic pores, inorganic pores (interP pores and intraP pores) and micro-fractures. Many pores are ink bottle-shaped characterized by narrow necks and wide bodies, while some others are slit-shaped. Pore size range from 0.305 nm to 98.5 μm. Pores with diameter of 0.305–2 nm (micro-pores), 2–50 nm (meso -pores), 50 nm-2 μm (macro-pores) and 2–98.5 μm (micro-fractures) account for 33.59%, 36.28%, 14.04% and 16.09% of the total pore volume, respectively. Moreover, shale permeability and specific surface area were calculated to be 0.005 mD and 39.44 m2/g, respectively, based on the full-scaled pore splicing. About 92% of specific surface area is contributed by pores with diameter of 0.305–5 nm. Micro-fractures connect with each other and form net-shaped structure with great connectivity from observational results. The micro-fractures with size of 20–98.5 μm provide the main permeability (about 90%). Micro-pores and small meso -pores in shale reservoirs provide large adsorption space for adsorbed gas, while micro-fractures enhance the seepage capability of shale gas, which are favorable for shale gas accumulation. [ABSTRACT FROM AUTHOR]

Carbonate-rich shale in salt lakes has become a potential target for petroleum exploration. A full understanding of storage space development characteristics is the basis for the efficient development of this kind of shale. In this study, the complex mineral composition and multiple pore structure of a typical carbonate-rich shale from the Paleogene Xin'gouzui Formation in the Jianghan Basin were systematically analyzed. The mixed shale and dolomitic shale were the main lithofacies types in the study area. Both of them were dominated by interparticle (interP) pores. However, their pore sizes are noticeably different. Pores with a size of <100 nm are the main compositions of the mixed shale, with an average volume proportion of 78.24%. Conversely, the dolomitic shale develops mainly micro-sized pores and micro-fractures, with a ratio of 70.46%. The difference in pore structure for different types of shales is closely associated with mineral composition. When particles of different sizes are mixed, most of the interP pores are prone to be filled by fine minerals (e.g., clay), resulting in relatively small pore sizes for the mixed shale. Homogeneous carbonate minerals are favorable for the residual of larger size interP pores. However, recrystallization and secondary enlargement of carbonate minerals can also lead to a significant decrease in pore diameter of interP pores. With these results, a storage space development model for different lithofacies shales was established. This work is crucial to further reveal the reservoir mechanisms and hydrocarbon scales of an argillaceous dolomite reservoir. • Quantification of lacustrine shale pore structure from multiple scales and dimensions. • The mixing of minerals with different diameters is the main factor leading to the narrower interparticle pores. • Established a dynamic response model of pore structure to mineralogical changes. [ABSTRACT FROM AUTHOR]

Abstract The organic matter-rich shales in Wufeng-Longmaxi Formation have been considered to be a high-quality source rock and a main shale-gas producer in southern China. As the material basis of shale gas, the organic matter content in shales exhibits a notable vertical difference in the Jiaoshiba area of Fulin shale gas field. This study integrated detailed geochemical analysis and sedimentary observations to investigate organic matter enrichment and depletion mechanism. Three intervals are identified by organic matter contents and their according variations. Six major lithofacies are identified based on mineral composition X-ray diffraction (XRD) analyses, microscopic observations and Focused Ion Beam-Scanning Electron Microscopy (FIB-SEM) data. Geochemical redox proxies (Mo-EF, U-EF, V/Cr and C org /P) indicate that organic matter-rich shales of Wufeng and bottom Longmaxi formation are deposited in anoxic conditions, whereas organic matter-lean shales of the middle to top Longmaxi formation are deposited in oxic environment. This pattern is influenced by both worldwide marine transgression and regional tectonic movement. The productivity proxies (P/Al, Cu/Al, Ni/Al, SiO 2-bio) indicate that the organic matter-rich Wufeng-Longmaxi shales were deposited under moderate to high surficial primary productivity. Increasing terrigenous influxes dominated organic matter dilution and may have been promoted by regional tectonic uplift. The organic matter enrichment or depletion mechanisms in each unit are controlled by different geological events. Enrichment was controlled by multiple reasons, including both global and regional factors, whereas depletion was mainly dominated by regional tectonic uplift. Additionally, the sequence stratigraphic boundaries coincide with organic matter shifting interfaces, indicating that high-resolution sequence stratigraphy of fine-grained sediments may have a certain effect on optimal reservoir predication. Conversely, boundaries of TOC and geochemical proxies may also help to subdivide sequence boundaries. Highlights • Six major lithofacies were identified from the mineral composition. • Anoxic conditions and high productivity controlled organic matter enrichment. • The organic matter depletion was mainly caused of sedimentary dilution. • Three models were developed to explain organic matter enrichment and depletion. [ABSTRACT FROM AUTHOR]

Abstract An important exploration breakthrough has been achieved in the western subsag of the Bozhong subbasin, but the hydrocarbon accumulation mechanism was not clear. The hydrocarbon migration and accumulation mechanism of the western subsag of the Bozhong subbasin is discussed based on the modeling of hydrocarbon migration pathways and the study of late-stage reactivation of neotectonic faults. Three processes for lateral petroleum migration and accumulation can be recognized in the studied area: 1) migration and accumulation along the T8 unconformity; 2) migration and accumulation within the Guantao Formaiton (N 1 g); and 3) interaction of migration and accumulation along the T8 unconformity and Guantao Formation (N 1 g). The reactivation of faults in the studied area began 5.1 Ma. Following hydrocarbon lateral migration, late-stage reactivated neotectonic faults serve as effective vertical conduits for hydrocarbon migration and accumulation into the shallow Minghuazhen Formation (N 1 m) reservoirs. The modeling results of preferential petroleum migration pathways (PPMPs) and favorable accumulation areas are consistent with the actual exploration results. Two kinds of potential exploration targets can be predicted in the northwestern Bozhong subbasin: the first kind is hydrocarbon accumulation areas near or within generative kitchens (e.g. Target 1); the other kind is hydrocarbon accumulation areas removed from the generative kitchens, but with hydrocarbon sourcing from multiple generative kitchen and numerous PPMPs (e.g. Target 2). Studying preferential petroleum migration pathways will help reduce exploration risk. Highlights • The T8 unconformity and Guantao Formation (N 1 g) carrier beds are favorable hydrocarbon lateral migration conduits. • Late-stage reactivated faults during neotectonism serve as favorable conduits for vertical hydrocarbon migration. • Proven oil fields usually have multiple generative kitchens and numerous preferential petroleum migration pathways. • Potential exploration targets can be predicted based on preferential petroleum migration pathways. [ABSTRACT FROM AUTHOR]

In the present work, we reported the exploration of WO 3 /BiVO 4 heterojunction photoanodes, which were consisted of one-dimensional WO 3 nanofiber (1D-WO 3 ) cores and BiVO 4 film shells. The 1D-WO 3 nanofibers were prepared by electrospinning, and the BiVO 4 outlayers were subsequently deposited around the surface of 1D-WO 3 fibers via a solution immersion process, leading to the construction of 1D-WO 3 /BiVO 4 heterojunctions. They had a maximum photocurrent density of 2.8 mA cm −2 at 1.23 V vs. RHE under AM 1.5 simulated solar light illumination, which was ∼20 times to that of pure 1D-WO 3 counterparts ( i.e. , 0.15 mA cm −2 ), and comparable to the best one of photoanodes based on WO 3 /BiVO 4 hybrids ever reported. Furthermore, the onset potential of FTO/1D-WO 3 /BiVO 4 photoanode was subsequently reduced, and the maximum incident photon-to-current efficiency ( IPCE ) was enhanced for ∼4 times in comparison to that of 1D-WO 3 counterparts. The mechanism for the enhanced PEC behaviors of WO 3 /BiVO 4 heterojunction photoanodes was proposed. [ABSTRACT FROM AUTHOR]

Gravity-flow deposits are important hydrocarbon exploration targets in most basins. In this study, an integration of geological, geophysical, and geochemical analysis is used to investigate the gravity-flow deposits and their petroleum prospects in the Oligocene Dongying Formation (E 3 d), Bozhong Subbasin, Bohai Bay Basin. Mass-transport deposits (MTDs) and channel-lobe complexes are the main gravity-flow depositional units. The mass-transport deposits (MTDs) show hummocky and chaotic reflections with poor continuity and variable amplitude. The channels display linear geomorphology with weak root-mean-square (RMS) amplitude, and the lobes are dominated by high-continuous and high-amplitude reflection at the terminal channels. The formation of gravity-flow deposits is primarily controlled by high sedimentation rate during a relative lowstand of lake level. The E 3 d 3 source rock has TOC contents in the range of 0.6–3.1%, Rock-Eval S 2 values in the range of 0.7–19.8 mg HC/g rock, and Hydrogen indices (HI) in the range of 100–600 mg/g TOC. The E 3 d 2 L source rock has TOC contents ranging from 0.5 to 1.9%, Rock-Eval S 2 values from 0.4 to 7.8 mg HC/g rock, and HI from 40 to 480 mg/g TOC. Both E 3 d 3 and E 3 d 2 L source rocks have good hydrocarbon-generation potential. The E 3 d 3 and E 3 d 2 L source rocks have entered the oil-generation peak window with the vitrinite reflectance (R o ) higher than 1.0%. Oils generated from the underlying source rocks shortly migrated to the overlying gravity-flow lithologic traps. The gravity-flow reservoirs could serve as potential and effective hydrocarbon exploration targets. [ABSTRACT FROM AUTHOR]

• Tyrosineprotein kinase, GPR15LG, KAZALD1, ADH1B, and thirty metabolites have been identified as potential biomarkers for renal ischemia–reperfusion injury. • Different durations of renal ischemia lead to unique pathological processes and varying components in the venous blood. • During the duration of renal ischemia lasting 40 min, the primary pathological process involves protein digestion and absorption. • During the extended duration of renal ischemia lasting 60 min, the primary pathological mechanisms involve central carbon metabolism, the glucagon signaling pathway, and pyruvate metabolism. Acute kidney injury (AKI) is frequently caused by renal ischemia–reperfusion injury (IRI). Identifying potential renal IRI disease biomarkers would be useful for evaluating AKI severity. We used proteomics and metabolomics to investigate the differences in renal venous blood between ischemic and healthy kidneys in an animal model by identifying differentially expressed proteins (DEPs) and differentially expressed protein metabolites (DEMs). Nine pairs of renal venous blood samples were collected before and at 20, 40, and 60 min post ischemia. The ischemia time of Group A, B and C was 20,40 and 60 min. The proteome and metabolome of renal venous blood were evaluated to establish the differences between renal venous blood before and after ischemia. We identified 79 common DEPs in all samples of Group A, 80 in Group B, and 131 in Group C. Further common DEPs among all three groups were Tyrosineprotein kinase, GPR15LG, KAZALD1, ADH1B. We also identified 81, 64, and 83 common DEMs in each group respectively, in which 30 DEMs were further common to all groups. Bioinformatic analysis of the DEPs and DEMs was conducted. This study demonstrated that different pathological processes occur during short- and long-term renal IRI. Tyrosine protein kinase, GPR15LG, Kazal-type serine peptidase inhibitor domain 1, and all- trans -retinol dehydrogenase are potential biomarkers of renal IRI. [ABSTRACT FROM AUTHOR]

The Oligocene succession of Dongying Formation in Qinnan depression in Bohai Bay Basin has preserved well-imaged lacustrine prograding shelf-edge scale clinoforms, providing a good opportunity to study the relationship between shelf-edge trajectory, stratal stacking patterns and sediment dispersal, and to investigate the effect of controlling factors on sediment dispersal shelf-edge trajectories in a lacustrine setting. 3D seismic volumes were used for defining seismic units, bounding surfaces, shelf-edge trajectories and sediment dispersal. Four seismic units have been subdivided, and four types of shelf-edge trajectories and the associated stratal stacking patterns have been recognized. Greater volume of sandstone in deep-water area tends to develop in seismic units with descending shelf-edge trajectory angles and tends be linked to lower shelf-edge trajectory angles. Differential tectonic subsidence rates along the shelf and along-strike variation in sediment supply were prime factors controlling lateral variability in trajectory, progradation and sediment dispersal. The evolution of shelf-edge trajectory can be subdivided into three stages. Local climate might play a major role in controlling lake-margin evolution during the first two stages, when dry hot weather foster basin floor fan deposition and descending trajectories, and humid cold weather hindered the development of basin floor fan and forms ascending trajectories. While differential tectonic subsidence could have the dominate role during the third stage, when climate signal can hardly be recognized and lateral variability in trajectory angles and sediment supply is most obvious. [ABSTRACT FROM AUTHOR]

The Shijiutuo uplift is an oil enriched uplift in the offshore Bohai Bay Basin. Petroleum migration is a key factor for oil enrichment in Neogene reservoirs far away from the hydrocarbon kitchen. In this article, an integration of geological, geophysical and geochemical analyses are employed to investigate the petroleum migration and accumulation on the Shijiutuo uplift. Hydrocarbons in the QHD32-6 and QHD33 oilfields are mainly originated from the third (E 2 s 3 ) and first (E 2 s 1 ) member of the Shahejie Formation. The shallow traps have significant contributions of late-stage E 2 s 1 -derived oil. Lateral petroleum migration is a major mechanism forming large oilfields on the Shijiutuo uplift. The large oilfields have multiple hydrocarbon kitchens, multiple source rocks, and numerous preferential petroleum migration pathways (PPMPs). Once petroleum arrives at the structural highs on the Shijiutuo uplift through the Guantao Formation (N 1 g) carrier-beds, neotectonic faults cutting through Guantao (N 1 g) and Minghuazhen (N 1 m L ) formations could serve as effective conduits for vertical petroleum migration. Neotectonic faults have experienced polycyclic fault activities. Fluid inclusions indicate episodic hydrocarbon charging. Crude oils display duplex properties of biodegradation and non-biodegradation, which is strong evidence for multiple and episodic oil charging on the Shijiutuo uplift. Finally, episodic petroleum charging along polycyclic neotectonic faults causes the late-stage E 2 s 1 -derived oils to occur in the shallow reservoirs. [ABSTRACT FROM AUTHOR]

A series of differential compaction faults was identified in the northern Bozhong Subbasin, Bohai Bay Basin, China, by using 3D seismic, well log, and lithology data. The differential compaction faults display two obvious characteristics. First, they develop along a lithologic boundary which separates thick sandstone from underlying mudstones. Facies and thickness change, such as an abrupt lithologic change between sandstone and mudstone, a lateral thickness change of overlying sandstone, are the basic controlling factors of these differential compaction faults. Second, they have a definite strike direction. According to the fault strike, the differential compaction faults can be divided into three groups: Group (a) have an approximate orthogonal strike with the tectonic faults, Group (b) display a similar strike with the slope, and Group (c) show radial strikes on the circular basement uplift. Tectonic faults influence the planform patterns of differential compaction faults in their near vicinity and induce these faults displaying an approximate orthogonal intersection with the late-period through-going faults (Group a). Basin slope promote the formation of differential compaction faults by downslope gravity sliding and cause faults parallel to the strike of slope (Group b). Circular basement topography generates isotropic stress and leads the differential compaction faults above the basement dominated by radial strikes (Group c). Production and geochemistry data is an evidence of differential compaction faults developed in a late period when the strata reach a certain burial depth that the source rocks enter the oil-generating window. The presence of thermogenic fluid within shallow reservoirs represents as evidence of hydrocarbon drained and migrated through the differential compaction faults. The differential compaction faults could serve as significant conduits for fluid expulsion and hydrocarbon accumulation in the Bohai Bay Basin, China. [ABSTRACT FROM AUTHOR]

The continental slope of the Taiwan Shoal, which has cultivated numerous submarine canyons, is located in a passive continental margin environment. However, the trend of the Taiwan Canyon, with its 45° intersection angle, is obviously different from that of the erosion valley downward along the continental slope. A distinct break is present in the lower segment of the Taiwan Canyon, which then extends from west to east parallel to the continental slope until finally joining the Manila Trench. By utilizing multiple-beam water depth data, high-resolution seismic data, and sediment cores, this study describes the topographic characteristics of the Taiwan Canyon and provides a preliminary discussion on the origin of the Taiwan Canyon and its effect on deepwater sediment. The terrain, landform, and sediment of the Taiwan Canyon exhibit segmentation characteristics. The upper segment is characterized primarily by erosion, downward cutting with a V shape, and wide development of sliding, slumping, and other gravity flow types. The middle segment is characterized mostly by U-shaped erosion-sedimentation transition and development of an inner levee. The lower segment is characterized primarily by sedimentation and development of a sediment wave. The bottom current has a significant reworking effect on the interior sediments of the canyon and forms reworked sands. The formation and evolution of the Taiwan Canyon is closely related to sediment supply, gravity sliding (slumping), faulting activities, and submarine impaling. Given the sufficient terrigenous clastic supply, the sediments along the continental shelf edge continuously proceed seaward; gliding and slumping in the front edge provide driving forces for the formation of the canyon. Faulting activities result in stratum crushing, and the gravity flow takes priority in eroding the relatively fragile stratum. Thus, the direction of the extension of the canyon crosses the surrounding erosion valley obliquely. Seamounts are formed through submarine impaling. Owing to seamount blocking, the lower segment of the canyon is turned toward the east-west direction. Large amounts of sediments overflow at the turning, forming sediment waves. [ABSTRACT FROM AUTHOR]

Organic anion-transporting polypeptides (Oatps) play important roles in transporting endogenous substances and xenobiotics into the liver and are implicated in drug-drug interactions. Many factors could influence their expression and result in alterations in drug disposition, efficacy and toxicity. This study was aimed to examine the development-, aging-, and sex-dependent Oatps expression in livers of rats. The livers from SD rats during development (− 2, 1, 7, 14, 21, 28, 35, and 60 d) and aging (60, 180, 540 and/or 800 d) were collected and total RNAs were extracted, purified, and subjected to real-time PCR analysis. Total proteins were extracted for western-blot analysis. Results showed that Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 were all hardly detectable in fetal rat livers, low at birth, rapidly increased after weaning (21 d), and reached the peak at 60 d. The Oatps remained stable during the age between 60–180 d, and decreased at elderly (540 and/or 800 d). After birth, Oatp1a1, Oatp1a4, and Oatp1b2 were all highly expressed in liver, in contrast, Oatp1a5 expression was low. Oatp expressions are male-predominant in rat livers. In the livers of aged rats, the Oatp expression decreased and shared a consistent ontogeny pattern at the mRNA and protein level. In conclusion, this study showed that in rat liver, Oatp1a1, Oatp1a4, Oatp1a5 and Oatp1b2 gene expressions are influenced by age and gender, which could provide a basis of individual variation in drug transport, metabolism and toxicity in children, elderly and women. [ABSTRACT FROM AUTHOR]

Abstract: Increased expression of the p22phox subunit of the NADPH oxidase complex may possibly contribute to both the enzyme׳s increased activation and the occurrence of oxidative stress during hyperhomocysteinaemia. However, the activation of peroxisome proliferator-activated receptor (PPAR) δ has been shown to inhibit p22phox expression. The purpose of this study was to elucidate the signaling pathway by which PPARδ activation regulated homocysteine-induced expression of p22phox. EA.hy926 cells were stimulated with homocysteine (Hcy) in the presence or absence of the PPARδ-specific agonist, GW0742, or of various signaling inhibitors, including the antioxidants N-acetylcysteine (NAC), NADPH oxidase inhibitor, diphenyleneiodonium (DPI), and the p38MAPK inhibitor, SB203580. Expression of p22phox mRNA and phospho-p38MAPK protein were measured by real-time PCR and western blot analysis, respectively, and reactive oxygen species were measured by fluorescence microscopy. Our data indicate that Hcy increased both the expression of p22phox in a concentration-dependent manner and also increased phosphoryation of p38 MAPK and reactive oxygen species production in a time-dependent manner. However, activation of the PPARδ signaling pathway by the agonist GW0742 reversed all these changes induced by Hcy. Furthermore, SB203580 prevented the increase in p22phox expression, and NAC and DPI not only inhibited Hcy-induced phosphorylation of p38MAPK, but also prevented expression of p22phox. These findings indicate that Hcy-induced expression of p22phox is regulated by the reactive oxygen species/p38MAPK pathway and that PPARδ activation is capable of attenuating this pathway by eliminating Hcy-induced reactive oxygen species production. [Copyright &y& Elsevier]

Highlights: [•] Transient neurobehavioral effects induced by nickel oral exposure. [•] Nickel deposition in cerebral cortex causes disturbance of aerobic metabolism. [•] Alteration in iron sulfur cluster scaffold protein may underlie effects of nickel. [ABSTRACT FROM AUTHOR]

Abstract: This study was aimed to investigate the effects of ginsenoside Rg1 (Rg1) on hematopoietic function of bone marrow in cyclophosphamide-induced bone marrow depression mice. Mice were given cyclophosphamide (150mg/kg, i.p. for three days) to produce bone marrow depression. Rg1 was then administrated at 7.5 and 15mg/kg by i.p. for seven days. Bone marrow cells number was counted, and the percentage of hematopoietic stem cells (Lin−Sca-1+c-kit+) was quantified by flow cytometry. The histology of femoral bone was examined by H&E staining. The expression of calcium-sensing receptor mRNA was determined by the real time RT-PCR. Rg1 (7.5 and 15mg/kg) protected against cyclophosphamide-induced bone marrow depression, as evidenced by increased bone marrow cell numbers and improved femoral bone morphology. The percentage of Lin−Sca-1+c-kit+ cells and lymphoid lineage CD3+ cells were lower in cyclophosphamide group, but returned towards normal after Rg1 treatment in both bone marrow and peripheral blood cells. Expression of calcium-sensing receptor mRNA was increased in bone marrow cells on the 10th day after cyclophosphamide, but it was returned to normal level after Rg1 treatment. Rg1 alone did not produce these changes in normal mice. These results demonstrated that Rg1 improved hematopoietic function of bone marrow in cyclophosphamide-induced myelosuppression. [Copyright &y& Elsevier]

The experiment was to explore the effect of prenatal feeding of compound Chinese herbal medicine preparation on the abortion rate and lambing rate of Hu sheep. A total of 2 100 ewes in late pregnancy were selected and randomly divided into two groups. Test group consisted of 1 100 ewes with 11 replicates, 100 sheep in each replicate. Control group was consisted of 1 000 ewes with 10 replicates and 100 sheep in each replicate. The sheep in control group were fed with basic feed, and sheep in test group were fed with test feed supplemented with 5 mL/head compound Chinese herbal medicine preparation for 10 d. The results showed that compared the control group, the abortion rate in test group was significantly reduced ( P<0.05). Compared with control group, the weak lambing rate and paralyzed sheep rate in test group were significantly reduced ( P<0.05). Compared with control group, the lamb mortality of test group was significantly reduced ( P<0.05), and the cure rate was significantly increased ( P<0.05). Compared with control group, the single tire weight, twin weight and triple tire weight were significantly increased ( P<0.05). The study indicates that the addition of 5 mL/head compound Chinese herbal medicine preparation to feed can improve the number of abortions, weak sheep and paralyzed sheep of pregnant ewes, and increase the lambing rate and the cure rate of lambs. [ABSTRACT FROM AUTHOR]

Abstract: Oxidative stress and mitochondrial dysfunction are involved in the pathogenesis of chronic liver cholestasis. Mitochondrial DNA (mtDNA) is highly susceptible to oxidative stress and mtDNA damage leads to mitochondrial dysfunction. This study aimed to investigate the mtDNA alterations that occurred during liver injury in patients with extrahepatic cholestasis. Along with an increase in malondialdehyde (MDA) levels and a decrease in ATP levels, extrahepatic cholestatic patients presented a significant increase in mitochondrial 8-hydroxydeoxyguanosine (8-OHdG) levels and decreases in mtDNA copy number, mtDNA transcript levels, and mtDNA nucleoid structure. In L02 cells, glycochenodeoxycholic acid (GCDCA) induced similar damage to the mtDNA and mitochondria. In line with the mtDNA alterations, the mRNA and protein levels of mitochondrial transcription factor A (TFAM) were significantly decreased both in cholestatic patients and in GCDCA-treated L02 cells. Moreover, overexpression of TFAM could efficiently attenuate the mtDNA damage induced by GCDCA in L02 cells. However, without its C-tail, ΔC-TFAM appeared less effective against the hepatotoxicity of GCDCA than the wild-type TFAM. Overall, our study demonstrates that mtDNA damage is involved in liver damage in extrahepatic cholestatic patients. The mtDNA damage is attributable to the loss of TFAM. TFAM has mtDNA-protective effects against the hepatotoxicity of bile acid during cholestasis. [Copyright &y& Elsevier]

Considering that the global optimal solutions often locate on or near the boundary of the feasible region for many constrained optimization problems, a novel genetic algorithm was proposed in this paper. The basic idea of the proposed algorithm was to put feasible solutions and infeasible solutions into two different containers respectively. Subsequently, a new designed crossover operator (named inward-outward crossover operator) was used to a feasible solution and a infeasible solution, then a line search along a potential decent direction was used to improve the offspring so as to find a good solution on or near to the boundary of feasible region. By this search procedure, the possibility for obtaining the globally optimal solution is obviously enhanced, and similarly, the convergent speed is also strengthened. The "particle swarm mutation" inherited the advantages of Particle Swarm Optimization (PSO) algorithm and searched for the potential solution along the direction of the best current particle and the direction of the best individual of the whole swarm in the past. Selection operator retained a constant rate of infeasible solutions. Numerical results indicate that the proposed algorithm can be efficient to get global optimal solutions or near to them in smaller population and less iteration times. [ABSTRACT FROM AUTHOR]

Mercury is an established worldwide environmental pollutant with well-known toxicity affecting neurodevelopment in humans, but the molecular basis of cytotoxicity and the detoxification procedure are still unclear. Here we examined the involvement of the canonical transient receptor potential (TRPC) channel in the mercury-induced cytotoxicity and the potential detoxification strategy. Whole-cell and excised patches, Ca2+ imaging, and site-directed mutagenesis were used to determine the mechanism of action of mercurial compounds on TRPC channels overexpressed in HEK293 cells, and cytotoxicity and preventive effect were investigated in cell culture models using small interfering RNA and pharmacological blockers. Mercury potently activates TRPC4 and TRPC5 channels. The extracellular cysteine residues (C553 and C558) near the channel pore region of TRPC5 are the molecular targets for channel activation by mercury. The sensitivity of mercury to TRPC5 is presumed to be specific because other divalent heavy metal pollutants, such as Cd2+, Ni2+, and Zn2+, had no stimulating effect, and TRPC3, TRPC6, TRPV1, and TRPM2 were resistant to mercurial compounds. The channel activity of TRPC5, as well as TRPC4, induced by mercury, was prevented by 2-aminoethoxydiphenyl borate and modified by a reducing environment. The inhibition of TRPC5 channels by specific TRPC5 pore-blocking antibody or by SKF-96365 alleviated the cytotoxicity, whereas the mercury chelator, meso-2,3-dimercaptosuccinic acid, showed nonselective prevention of cell survival. Silencing of the TRPC5 gene reduced the mercury-induced neuronal damage. These results indicate that mercurial compounds are activators for TRPC5 and TRPC4 channels. Blockade of TRPC channels could be a novel strategy for preventing mercury-induced cytotoxicity and neurodevelopment impairment. [ABSTRACT FROM AUTHOR]

Recent studies suggest that oxidative stress and mitochondrial dysfunction play important roles in the neurotoxicity of nickel. Because mitochondrial DNA (mtDNA) is highly vulnerable to oxidative stress and melatonin can efficiently protect mtDNA against oxidative damage in various pathological conditions, the aims of this study were to determine whether mtDNA oxidative damage was involved in the neurotoxicity of nickel and to assay the neuroprotective effects of melatonin in mtDNA. In this study, we exposed mouse neuroblastoma cell lines (Neuro2a) to different concentrations of nickel chloride (NiCl2, 0.125, 0.25, and 0.5 m m) for 24 hr. We found that nickel significantly increased reactive oxygen species (ROS) production and mitochondrial superoxide levels. In addition, nickel exposure increased mitochondrial 8-hydroxyguanine (8-OHdG) content and reduced mtDNA content and mtDNA transcript levels. Consistent with this finding, nickel was found to destroy mtDNA nucleoid structure and decrease protein levels of Tfam, a key protein component for nucleoid organization. However, all the oxidative damage to mtDNA induced by nickel was efficiently attenuated by melatonin pretreatment. Our results suggest that oxidative damage to mtDNA may account for the neurotoxicity of nickel. Melatonin has great pharmacological potential in protecting mtDNA against the adverse effects of nickel in the nervous system. [ABSTRACT FROM AUTHOR]

Abstract: Mitochondrial dysfunction is thought to be a part of the mechanism underlying nickel-induced neurotoxicity. L-carnitine (LC), a quaternary ammonium compound biosynthesized from the amino acids lysine and methionine in all mammalian species, manifests its neuroprotective effects by improving mitochondrial energetics and function. The purpose of this study was to investigate whether LC could efficiently protect against nickel-induced neurotoxicity. Here, we exposed a mouse neuroblastoma cell line (Neuro-2a) to different concentrations of nickel chloride (NiCl2) (0.25, 0.5, 1, and 2mM) for 24h, or to 0.5mM and 1mM NiCl2 for various periods (0, 3, 6, 12, or 24h). We found that nickel significantly increased the cell viability loss and lactate dehydrogenase (LDH) release in Neuro-2a cells. In addition, nickel exposure significantly elevated reactive oxygen species (ROS) and malondialdehyde (MDA) levels, disrupted the mitochondrial membrane potential (ΔΨm), reduced adenosine-5′-triphosphate (ATP) concentrations and decreased mitochondrial DNA (mtDNA) copy numbers and mtRNA transcript levels. However, all of the cytotoxicities and mitochondrial dysfunctions that were triggered by nickel were efficiently attenuated by pretreatment with LC. These protective effects of LC may be attributable to its role in maintaining mitochondrial function in nickel-treated cells. Our results suggest that LC may have great pharmacological potential in protecting against the adverse effects of nickel in the nervous system. [Copyright &y& Elsevier]

Abstract: This paper presents a high-accuracy method for fine registration of two partially overlapping point clouds that have been coarsely registered. The proposed algorithm, which is named dual interpolating point-to-surface method, is principally a modified variant of point-to-surface Iterative Closest Point (ICP) algorithm. The original correspondences are established by adopting a dual surface fitting approach using B-spline interpolation. A novel auxiliary pair constraint based on the surface fitting approach, together with surface curvature information, is employed to remove unreliable point matches. The combined constraint directly utilizes global rigid motion consistency in conjunction with local geometric invariant to reject false correspondences precisely and efficiently. The experimental results involving a number of realistic point clouds demonstrate that the new method can obtain accurate and robust fine registration for pairwise 3D point clouds. This method addresses highest accuracy alignment with less focus on recovery from poor coarse registrations. [Copyright &y& Elsevier]

Abstract: Diabetic vascular complications are related to a combination of oxidative stress and hyperglycemia. Here we investigate the effect and mechanism of soy isoflavones on oxidative stress-induced endothelial cell injury. Oxidative stress was modeled in primary cultured human umbilical vein endothelial cells by incubation with H2O2 and high glucose. Genistein and daidzein protected the cells against H2O2-induced apoptosis and their protective actions were abolished by ICI 182780, an estrogen receptor antagonist. The inhibition of cell proliferation by oxidative stress was prevented by genistein and daidzein under normal glucose conditions, but they were less effective at high glucose levels. Genistein and daidzein upregulated the estrogen receptor ERβ and increased Bcl-2 expression. Silencing of Bcl-2 with siRNA abolished the protection of genistein. Moreover, inhibition of the PI3K and Rho A/Rho kinase pathways by wortmannin and Y-27632 altered the effects of genistein and daidzein on cell survival. We conclude that oxidative stress-induced apoptosis and cell proliferation inhibition can be prevented by soy isoflavones via the regulation of ERβ and Bcl-2/Bax expression and modulation of cell survival signaling, such as the PI3K pathway. These findings imply that multiple mechanisms are involved in the beneficial effects of soy isoflavone supplements for diabetic endothelial injury. [Copyright &y& Elsevier]

The lacustrine Dameigou organic-rich shale of the northern Qaidam Basin is a particularly promising play for recent unconventional oil and gas exploration in China. Deposition was associated with arid intervals during the otherwise humid Middle Jurassic, but the depositional mechanism and organic matter enrichment processes are poorly understood. This study integrates high-resolution organic and inorganic geochemical proxies with detailed sedimentary observations for samples from the Chaiye (CY1) borehole, located in the Yuqia Depression, to investigate the depositional environment and development of the Dameigou shales. Four major lithofacies, including sandy mudstones, oil shale, organic-rich mudstone, and argillaceous mudstone, were identified through detailed microscopic observation and mineralogical analyses. Geochemical paleoclimate proxies (CIA, Fe/Mn and Mg/Ca) indicate that humidity fluctuations primarily drove the lithofacies variation. Other geochemical proxies, including terrigenous supply (Al 2 O 3 , Ti 2 O and regular sterane), lake salinity (Sr/Ba, S/TOC and Ga), redox conditions (V/Cr, U/Th and Pr/Ph), and primary productivity (Ba xs , P xs) indicate that climatic variability exerted a first-order control on the chemical evolution of the lake and the development of organic-rich shale in the Yuqia area. During arid intervals, fresh water supply through precipitation and river runoff weakened, leading to an increase in salinity and water column stratification. As a result, surface water became brackish and oxygen-rich, promoting growth of algae, but density stratification drove the bottom waters to anoxia, providing favorable conditions for organic matter preservation. Recycling of nutrients such as phosphorus under anoxic conditions further promoted eutrophication and high productivity in the surface water, which ultimately promoted the precipitation of carbonate minerals. • Some arid climate disturbances were recognized in the Jurassic Dameigou Formation. • Salinity and redox conditions of the lake water were controlled by climate variation. • Arid climate transition caused the enhancement of primary productivity. • Water column stratification favored the organic-rich oil shale development. [ABSTRACT FROM AUTHOR]

Mammalian homologues of Drosophila melanogaster transient receptor potential (TRP) are a large family of multimeric cation channels that act, or putatively act, as sensors of one or more chemical factor. Major research objectives are the identification of endogenous activators and the determination of cellular and tissue functions of these channels. Here we show the activation of TRPC5 (canonical TRP 5) homomultimeric and TRPC5–TRPC1 heteromultimeric channels by extracellular reduced thioredoxin, which acts by breaking a disulphide bridge in the predicted extracellular loop adjacent to the ion-selectivity filter of TRPC5. Thioredoxin is an endogenous redox protein with established intracellular functions, but it is also secreted and its extracellular targets are largely unknown. Particularly high extracellular concentrations of thioredoxin are apparent in rheumatoid arthritis, an inflammatory joint disease that disables millions of people worldwide. We show that TRPC5 and TRPC1 are expressed in secretory fibroblast-like synoviocytes from patients with rheumatoid arthritis, that endogenous TRPC5–TRPC1 channels of the cells are activated by reduced thioredoxin, and that blockade of the channels enhances secretory activity and prevents the suppression of secretion by thioredoxin. The data indicate the presence of a previously unrecognized ion-channel activation mechanism that couples extracellular thioredoxin to cell function. [ABSTRACT FROM AUTHOR]

Rottlerin has been widely accepted as a specific inhibitor of protein kinase Cδ (PKCδ); however, recent data suggest that the specificity of this compound become a question. Herein, we address this issue using a lens organ culture system, as PKCδ might regulate the gap junction permeability in lens. Interestingly, we found that rottlerin induced the degradation of connexin50 more rapidly than that of PKCδ. Furthermore, comparison of rottlerin with a protonophore, carbonylcyanide-4-(trifluoromethoxy)-phenylhydrazone (FCCP) that shares many characteristics with rottlerin, showed that both rottlerin and FCCP dramatically increased lens weight over time. This increase in lens weight was partially reversed by depletion of extracellular calcium with ethyleneglycoltetraacetic acid (EGTA) or by blocking L-type calcium channels with verapamil, suggesting rottlerin may induce calcium influx. Indeed, the rapid degradation of connexin50 (but not PKCδ) induced by rottlerin and FCCP was blocked by EGTA. In addition, rottlerin and FCCP also induced degradation of connexin46, filensin, vimentin and CP49. In order to determine whether this protein degradation is associated with the decrease of ATP due to uncoupling mitochondria by rottlerin, ATP content in lenses with different treatments were examined. The result indicated that EGTA had no effect on lens ATP content. Taken together, these data suggest that rottlerin, like FCCP, induces calcium influx, leading to protein degradation and cleavage in the lens, and that this effect is unrelated to the inhibition of PKCδ. Thus, extreme caution must be taken when considering use of rottlerin as a PKCδ inhibitor. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we determine all connected 5-arc transitive cubic Cayley graphs on the alternating group ; there are only two such graphs (up to isomorphism). By earlier work of the authors, these are the only two non-normal connected cubic arc-transitive Cayley graphs for finite nonabelian simple groups, and so this paper completes the classification of such non-normal Cayley graphs. [Copyright &y& Elsevier]

Abstract: The objective of this study is to determine the effects of Pb2+ on N-methyl-d-aspartate receptor (NMDAR) subunits—NR1C1, NR2A and NR2B in primary cultured neuronal cells. We hypothesize that l-glutamic acid (GA) reverses Pb2+-induced NMDAR damage. Neuronal cells were isolated from the fetus brain at 18–20th day of gestation of pregnant Sprague Dawley (SD) rats. All experiments were included three independent cell preparations (N =3). The neuronal cells were exposed to Pb2+ (10−10, 10−9, 10−8 and 10−7 M) for 24h. Neurons were pretreated with NMDAR agonist—l-glutamic acid (GA) (200μM) and antagonists dizocipine (MK-801, 50nM) for 1h and then exposed to 10−7 M of Pb2+ for 24h. Finally, GA at 2, 0.2 and 0.02mM was incubated with neurons prior to Pb2+ exposure. Aliquots of NR1, NR2A and NR2B proteins from cell homogenate were immunoprecipitated with protein A agarose and detected by Western blotting. The addition of GA unconventionally reversed the reductions of NMDAR by Pb at protein levels, whereas MK-801 exacerbated Pb2+-induced damage. The protection by GA against Pb2+-induced reduction of NMDAR was dose-dependent. These findings suggest that the administration of GA may be a potential approach to intervene the Pb2+-induced NMDAR alterations. [Copyright &y& Elsevier]

1 2-aminoethoxydiphenyl borate (2-APB) has been widely used to examine the roles of inositol 1,4,5-trisphosphate receptors (IP3Rs) and store-operated Ca2+ entry and is an emerging modulator of cationic channels encoded by transient receptor potential (TRP) genes. 2 Using Ca2+-indicator dye and patch-clamp recording we first examined the blocking effect of 2-APB on human TRPC5 channels expressed in HEK-293 cells. 3 The concentration-response curve has an IC50 of 20 microM and slope close to 1.0, suggesting one 2-APB molecule binds per channel. The blocking effect is not shared by other Ca2+ channel blockers including methoxyverapamil, nifedipine, N-propargylnitrendipine, or berberine. 4 In whole-cell and excised membrane patch recordings, 2-APB acts from the extracellular but not intracellular face of the membrane. 5 Block of TRPC5 by 2-APB is less at positive voltages, suggesting that it enters the electric field or acts by modulating channel gating. 6 2-APB also blocks TRPC6 and TRPM3 expressed in HEK-293 cells, but not TRPM2. 7 Block of TRP channels by 2-APB may be relevant to cell proliferation because 2-APB has a greater inhibitory effect on proliferation in cells overexpressing TRPC5. 8 Our data indicate a specific and functionally important binding site on TRPC5 that enables block by 2-APB. The site is only available via an extracellular route and the block shows mild voltage-dependence. [ABSTRACT FROM AUTHOR]

Abstract: A plethora of protein kinase C (PKC) isoforms play important roles in regulating synaptic plasticity and neurotransmitter release. Even though, most PKC isoforms are involved in Pb-induced neuronal toxicity, its mechanism is still unclear. The current study addresses the effect of Pb on PKC isoforms in different regions of the developing rat brain. Sprague–Dawley (SD) pregnant rats were exposed to 0.1% Pb as lead acetate dissolved in distilled deionized water (DDW) from gestation day 6 through 21 postnatal day (PND). Control rats were allowed to drink DDW. Pups were sacrificed on PND 1, 5, 10 and 45. Rat brain was immediately excised and separated into the brain stem (BS), the cerebellum (CB), the hippocampus (HC) and the frontal cortex (FC). The Pb level in different regions of the brain was determined using an analytical graphite tube atomizer (Varian). Typical PKC (α, β, γ), novel PKC (ε) and atypical PKC (μ) in the above brain regions were enriched by immunoprecipitation and later were assayed by Western blotting. The total, calcium-dependent and -independent PKC activities were determined by the radioactivity of total γ-32P transferred to histone. The results indicated that on PND 1, Pb reduced the PKC-γ protein in HC and FC, whereas on PND 5 the proteins of PKC isoforms (α, β, γ, ε, μ) in HC and FC were significantly reduced. These reductions in PKC proteins were higher in membrane fractions than in cytosolic fractions. On PND 10, Pb reduced all PKC isoforms. However, on PND 45, Pb had no significant effect on all PKC isoforms except ε. Pb inhibited the total PKC activity by 70% on PND 1 and 5, the bulk of these PKC activities were calcium-dependent. The results suggest that during early stages of the rat brain development, Pb exposure decreased PKC activities and also reduced PKC isoforms including PKC-γ and ε which are reported to have roles in the memory formation and long-term potentiation (LTP). [Copyright &y& Elsevier]

For a positive integer s, a graph Γ is called s-arc transitive if its full automorphism group AutΓ acts transitively on the set of s-arcs of Γ. Given a group G and a subset S of G with S=S-1 and 1∉S, let Γ=Cay(G,S) be the Cayley graph of G with respect to S and GR the set of right translations of G on G. Then GR forms a regular subgroup of AutΓ. A Cayley graph Γ=Cay(G,S) is called normal if GR is normal in AutΓ. In this paper we investigate connected cubic s-arc transitive Cayley graphs Γ of finite non-Abelian simple groups. Based on Li’s work (Ph.D. Thesis (1996)), we prove that either Γ is normal with s≤2 or G=A47 with s=5 and AutΓ A48. Further, a connected 5-arc transitive cubic Cayley graph of A47 is constructed. [Copyright &y& Elsevier]