The shale gas exploration and development in Sichuan Basin had achieved a major breakthrough remarkably. However, the business development focused on the marine shale gas in shallow layers (vertical ...depth < 3500 m) of the Wufeng Formation-Longmaxi Formation alone. Therefore, the deep shale gas (vertical depth > 3500 m) business development in Wufeng Formation-Longmaxi Formation is the key to the rapid growth of shale gas production in the Sichuan Basin. In the literature, authors analyzed the geological characteristics of the deep shale gas of the Wufeng Formation - Longmaxi Formation in southern Sichuan Basin through particular dissection and analysis of deep wells in comparison to the shallow layers. The thickness of organic-rich shale in the deep region of southern Sichuan Basin measures to be more than 120 m, which is larger than that of the shallow layers in Fuling area. The vertical TOC change remains constant whereas the thickness of high-quality shale is approximately forty meters in both regions. Nevertheless, the RO is higher in the deep region of southern Sichuan Basin. The calcareous content of the organic shale increases while the silicon content decreases from the Fuling area down as it gets deeper into the region in southern Sichuan Basin. It is quite evident in research that the shales in the Wufeng Formation – Longmaxi Formation of the deep to shallow layers of southern Sichuan that there are not many differences in depositional environment, lithology, TOC, etc. However, there are four major differences: (1) The porosity of shale in the deep region of southern Sichuan Basin is higher than that in Fulin gas field due to the corrosion pore. (2) The gas-bearing properties are better in the deep regions of southern Sichuan Basin because they have better preservation condition compared to that of the shallow region of Fuling. (3) However, gas-bearing properties are worse in the local region of stronger structure deformation and the basin boundary fault zone. (4) The shale gas resources in the deep regions of southern Sichuan Basin are great and have wide prospects for exploration and development. In order for a breakthrough to be generated in deep shale gas commercial development in the soonest possible time, authors propose the following: utilize strengthening evaluation of small layer contrasting so as to explain fine structure and predict fracture; strengthen the research on drilling and fracturing technology for deep shale gas; strengthen research on wells column; and support technology for efficient production of shale gas.
•SO42−, NO3− and NH4+, which accounted for 54–61% of the total PM mass, were the main fractions of PM2.5 in haze formation during spring 2013.•Different haze episodes were dominated by different ...fraction due to meteorological conditions and sources.•Southeasterly air mass favours accumulation of PM and formation of haze.
A continuous daily PM2.5 sampling campaign from 10 April till 8 June 2013, including three haze episodes, was conducted in Beijing. Chemical species, including EC, OC, water-soluble ions and inorganic elements, were analysed by a thermal/optical carbon analyser, IC and ICP-MS, respectively. A comparison of air quality during such haze episodes in relation to clear air situations, as well as the differences between the haze episodes was emphasised. The results showed that the most important fractions of PM2.5 during haze were SO42−, NO3− and NH4+ (namely, SNA) which together accounted for 54–61% of the total PM2.5 mass. Estimated secondary organic carbon (SOC) was also found to be increased during haze, but the relative increase compared to clear days was much lower than for SNA, leading to a decrease in relative contribution of SOC to PM2.5 in the observed haze events. Cluster analyses from back trajectories showed four air mass clusters during spring 2013 and air flow, which was from the south-easterly directions, might favour the accumulation of PM2.5, especially SNA and anthropogenic elements. All these results proved that the anthropogenic air pollution in the Southeast of Beijing was responsible for the formation of hazes in Beijing during spring 2013.
We extend the array theory to design 2D curved coding metasurfaces in order to achieve arbitrary wavefront control. The extended array theory establishes the relationship between wavefront and ...curved-surface, which provides a simple and effective method to obtain the layout of desired metasurfaces. According the theory, we present 2D curved metasurfaces with 3-bit coding elements. Both simulations and measurements demonstrate that the proposed designs can manipulate wavefront effectively. For normal incidence, the aperture efficiency of normal reflection is more than 90%. For general oblique incidence, the proposed designs almost meet the expectances, but the aperture efficiency decreases with the increase of desired scattering elevation angle. The curved coding metasurfaces are expected to be applied to many devices such as conformal antenna array.
Background
Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest malignancies to date. The impressively developed stroma that surrounds and modulates the behavior of cancer cells is ...one of the main factors regulating the PDAC growth, metastasis and therapy resistance. Here, we postulate that stromal and cancer cell compartments differentiate in protein/lipid glycosylation patterns and analyze differences in glycan fragments in those compartments with clinicopathologic correlates.
Results
We analyzed native glycan fragments in 109 human FFPE PDAC samples using high mass resolution matrix-assisted laser desorption/ionization Fourier-transform ion cyclotron resonance mass spectrometric imaging (MALDI-FT-ICR-MSI). Our method allows detection of native glycan fragments without previous digestion with PNGase or any other biochemical reaction. With this method, 8 and 18 native glycans were identified as uniquely expressed in only stromal or only cancer cell compartment, respectively. Kaplan–Meier survival model identified glycan fragments that are expressed in cancer cell or stromal compartment and significantly associated with patient outcome. Among cancer cell region-specific glycans, 10 predicted better and 6 worse patient survival. In the stroma, 1 glycan predicted good and 4 poor patient survival. Using factor analysis as a dimension reduction method, we were able to group the identified glycans in 2 factors. Multivariate analysis revealed that these factors can be used as independent survival prognostic elements with regard to the established Union for International Cancer Control (UICC) classification both in tumor and stroma regions.
Conclusion
Our method allows in situ detection of naturally occurring glycans in FFPE samples of human PDAC tissue and highlights the differences among glycans found in stromal and cancer cell compartment offering a basis for further exploration on the role of specific glycans in cancer–stroma communication.
Currently, gastric cancer is considered one of the major causes of high mortality and morbidity worldwide. Recent advances in therapeutics, clinical treatment, staging procedures, and imaging ...techniques are high, yet the prevalence of gastric cancer has not been reduced. Usage of the synthetic drug has many side effects that can lead to other ailments. Gedunin, a phytochemical derived from
Azadirachta indica
(neem tree), exhibits several pharmacological activities including antitumor, anti-inflammatory, antiulcer, antipyretics, antibacterial, antifungal, anti-diabetic, and antimalarial properties. In the current investigation, the effect of gedunin on the cell viability; reactive oxygen species (ROS) generation by DCFH-DA staining; mitochondrial membrane potential (MMP) by Rh-123 staining; apoptosis by AO/EtBr staining; cell migration and wound healing ability by wound scratch assay; and Bcl-2, Bax, caspase-3, and caspase-9 by ELISA techniques were analyzed in the AGS cells. The treatment with gedunin effectively inhibited the cell viability with IC
50
= 20µM, increased the ROS generation, and triggered the apoptosis in AGS cells. The gedunin-treated AGS cells also demonstrated a decreased MMP status. The increment in the ROS generation leads to oxidative stress which in turn induce the apoptosis. The activity of Bax gene was upregulated and the activity of Bcl-2 gene was down-regulated in the AGS cells after the treatment with gedunin. In the AGS cells treated with gedunin, the caspase-3 and caspase-9 activities were increased. In overall, these findings suggested that gedunin can be used as a potent chemotherapeutic agent in the future to treat gastric cancer.
Synergistic effects have previously been observed for a natural compound, tetrandrine (TET), with fluconazole (FLC) in vitro and in the treatment of Candida albicans-infected mice. To investigate the ...mechanisms of these synergistic effects, 16 strains of C. albicans from the same parent but with different FLC sensitivities were examined using flow cytometry and fluorescent spectrophotometry. Rhodamine 123 (Rh123)-positive cells and intracellular Rh123 fluorescence intensity were determined in accumulation/efflux experiments involving no or a noncytotoxic dose of TET. Total RNA extracted from each strain was used to compare the expressions of drug efflux pump genes in FLC-susceptible, -susceptible dose-dependent, and -resistant strains before and 24 h after TET administration. Accumulation experiments determined that mean percentages of Rh123-positive cells were 26.65% (TET-free) and 70.99% (TET 30 μg/ml), and mean respective intracellular Rh123 fluorescence intensities were 11.34 and 18.00. Efflux experiments showed that percentages of Rh123-positive cells were 1.79% (TET free) and 42.57% (TET 30 μg/ml), respectively, and respective mean intracellular Rh123 fluorescence intensities were 0.74 and 2.19. Differences in MDR1, FLU1, CDR1, and CDR2 expression levels in the absence of TET were statistically significant (p<0.05) between FLC-susceptible, -susceptible dose-dependent, and -resistant strains. Compared with TET-free conditions, 24 h TET-treated strains showed statistically different (p<0.05) expression of MDR1 (FLC-resistant strain), FLU1 (FLC-susceptible dose-dependent and -resistant strains), and CDR1 and CDR2 (FLC-susceptible, -susceptible dose-dependent, and -resistant strains). Thus TET can inhibit the C. albicans drug efflux system and reduce drug efflux. Its mechanism of action is related to the inhibition of expression of the drug efflux pump genes MDR1, FLU1, CDR1, and CDR2.
In tight reservoirs, the rock formations are typically less porous and permeable, which makes it more difficult for hydrocarbons to flow through them. In addition to length and conductivity, the ...height of a fracture is another critical parameter of the hydraulic fracturing treatments in unconventional tight/shale formations, which determines the stimulated reservoir volume. If the fracture height is too shallow, the volume of rock exposed to the fluid and proppant may not be sufficient to improve the reservoir’s production significantly. Conversely, if the fracture height is too deep, the injected fluid may not be able to propagate high enough to reach the desired formation. However, after years of research, fracture height has often been simplified in traditional or recent studies of fracture simulation and estimation. The objective of this work is to propose an innovative way to simulate the hydraulic fracturing process in both horizontal and vertical directions in tight formations with a well-built finite element numerical model. Fracture toughness KIC is calculated based on the Brazilian test. Vertical fracturing fluid was also considered, and the model was validated by fracture height monitoring data from a stimulated well in the Montney formation. The influence of rock and fluid properties on the fracture height propagation was studied thoroughly with sensitivity analysis. The results indicated the fracture height prediction model was in good accordance with the monitoring data collected from the field, with an error margin of 7.2%. Sensitivity analysis results showed that a high Young’s modulus led to a larger stress intensity factor at the fracture tip, thus further advancing the fracture. Minimum horizontal stress also tends to facilitate the fracture to propagate. The influence of Poisson’s ratio and fluid viscosity on fracture height propagation was also investigated.
Background: Obesity is a principal risk factor for the development of type 2 diabetes and cardiovascular diseases. Natural plants and/or foods play an important role in the management of obesity. ...Acalypha australis L. (AAL) is a kind of potherb popular among Asian populations, and it is also consumed as a food ingredient and traditional herbal medicine. Objective: We investigated the effects of water extract from AAL on high-fat-diet (HFD)-induced obese mice and 3T3-L1 adipocytes to develop a new functional food material. Design: Nine-week-old male mice were randomly divided into control (chow diet, n = 6) and HFD (n = 30) group. From 12-weeks onward, mice in the HFD group were further separated into model (saline, 6 mL/kg), simvastatin (0.11 mg/mL, 6 mL/kg), and AAL treatment (low, middle, and high dosage: 300, 600, and 900 mg/kg) group, with 6 animals per group, while mice in the control group were treated with saline (6 mL/kg). Food intake, body/fat weight, liver/kidney indexes, and lipid profiles were determined. Tissues were fixed with formalin for pathological examination. Western blotting and PCR were performed to evaluate the protein and mRNA expression in 3T3-L1 adipocytes. Oil Red O staining was used to determine lipid accumulation. Results: AAL administration significantly suppressed body weight gain, and reduced fat pad weight and Lee’s index in obese mice, but had no effect on liver/kidney index. AAL also reduced serum cholesterol, triglyceride, and LDL-C and increased HDL-C levels. Histological analysis revealed that AAL significantly ameliorated lipid accumulation in the liver and subcutaneous adipose tissue. In vitro, Oil Red O staining showed that AAL inhibited adipose differentiation by down-regulating the gene and protein expression of PPARγ and C/EBPα. AAL also reversed HFD-induced intestinal dysbacteriosis. Conclusion: AAL water-soluble extract has a significant anti-adipogenic effect in the HFD-induced obese mice model.
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