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Hydraulic fracturing fracture propagation is the main factor affecting the fracturing effect. In view of the more diversified selection of fracturing fluid, the problem of fracture propagation in non‐Newtonian fluid fracturing is often encountered in fracturing. In this paper, the influencing factors of fracture propagation of non‐Newtonian fluid fracturing fluid are analyzed. Based on PKN model, a three‐dimensional fracture propagation model considering the rheology and filtration of fracturing fluid is established, the better fracture shape simulation results are given, and the effects of fluid properties, rock physical properties, and injection parameters on fracture propagation are analyzed in detail. The research shows that (1) in the process of fracture propagation, the fracture length and width gradually increase, and the corresponding pressure in the fracture also increases. The overall increase trend is that the growth is rapid in the initial stage of fracturing and gradually slows down in the later stage. (2) The greater the consistency coefficient and rheological index, the greater the fracture width and pressure in the fracture, and the easier it is to form wide fracture. The larger the filtration coefficient is, the weaker the fracture forming ability is, and the fracture width, length, and pressure in the fracture are reduced. (3) Rock physical properties have a certain influence on fracture propagation, Young's modulus has a great influence on fracture propagation, while Poisson's ratio has little influence on it. However, the larger the Young's modulus, the more difficult the fracture is to expand, and the smaller the corresponding fracture width. (4) The larger the pump injection rate, the larger the fracture size and the higher the pressure in the fracture. The model can provide a theoretical basis for fracturing design and fracture shape prediction.

Gravel packing is one of the most commonly used well‐completion methods for controlling sand production in deepwater horizontal gas wells. Both the gravel‐packing mechanisms and the technical difficulties of gravel packing in a horizontal well are discussed in this paper. Subsequently, packing simulations were conducted based on geological data from a well in the LS gas field in the northern South China Sea. The factors influencing the gravel‐packing process were quantitatively analyzed. The influences of the pump rate, carrying fluid leak‐off ratio, and density of gravel on the sand‐dune ratio of the α‐wave, height of the sand dune, packing length of the α‐wave, and packing pressure were analyzed. The results show that the pipe string injection friction is the largest at the slurry injection stage and the α‐wave packing stage. In the β‐wave packing stage, the downhole horizontal flow friction becomes the main pressure loss. The friction increased when the β‐wave packing reached the heel of the horizontal wells. As a result, the packing pressure can easily exceed the formation fracture pressure. Furthermore, the lower the pump rate, the higher the sand‐dune ratio, which would cause premature screen‐out and blockage. Therefore, optimizing the pump rate is essential to ensure that the sand‐dune ratio meets the designed requirements. Under a certain leak‐off rate, the lower the gravel density, the longer the packing length of the α‐wave. For a long horizontal well, the step‐down method can be used to control the packing pressure during the β‐wave packing stage. The results provide technical support for field gravel packing.

Magnetotactic bacteria (MTB) are phylogenetically diverse prokaryotes that can produce intracellular chain-assembled nanocrystals of magnetite (Fe3 O4 ) or greigite (Fe3 S4 ). Compared with their wide distribution in the Alpha-, Eta- and Delta-proteobacteria classes, few MTB strains have been identified in the Gammaproteobacteria class, resulting in limited knowledge of bacterial diversity and magnetosome biomineralization within this phylogenetic branch. Here, we identify two magnetotactic Gammaproteobacteria strains (tentatively named FZSR-1 and FZSR-2 respectively) from a salt evaporation pool in Bohai Bay, at the Fuzhou saltern, Dalian City, eastern China. Phylogenetic analysis indicates that strain FZSR-2 is the same species as strains SHHR-1 and SS-5, which were discovered previously from brackish and hypersaline environments respectively. Strain FZSR-1 represents a novel species. Compared with strains FZSR-2, SHHR-1 and SS-5 in which magnetite particles are assembled into a single chain, FZSR-1 cells form relatively narrower magnetite nanoparticles that are often organized into double chains. We find a good relationship between magnetite morphology within strains FZSR-2, SHHR-1 and SS-5 and the salinity of the environment in which they live. This study expands the bacterial diversity of magnetotactic Gammaproteobacteria and provides new insights into magnetosome biomineralization within magnetotactic Gammaproteobacteria.

Porous molecular crystals sustained by hydrogen bonds and/or weaker connections are an intriguing type of adsorbents, but they rarely demonstrate efficient adsorptive separation because of poor structural robustness and tailorability. Herein, we report a porous molecular crystal based on hydrogen-bonded cyclic dinuclear AgI complex, which exhibits exceptional hydrophobicity with a water contact angle of 134°, and high chemical stability in water at pH 2-13. The seemingly rigid adsorbent shows a pore-opening or nonporous-to-porous type butane adsorption isotherm and complete exclusion of isobutane, indicating potential molecular sieving. Quantitative column breakthrough experiments show slight co-adsorption of isobutane with an experimental butane/isobutane selectivity of 23, and isobutane can be purified more efficiently than for butane. In situ powder/single-crystal X-ray diffraction and computational simulations reveal that a trivial guest-induced structural transformation plays a critical role.

We create textual information indices using corporate social responsibility (CSR) information extracted from IPO prospectuses in China. We use the indices to measure the issuers’ corporate social performance (CSP) and corporate environmental performance (CEP) and assess how the stock market reacts. We find that CSP disclosure is significantly related to the post‐market performance of the firm. Specifically, better CSP disclosure is correlated with higher post‐IPO listing holding period returns among firms that do not disclose donations or environmental expenditures, although the association does not hold for firms that make donations and environmental expenditures. In addition, institutional investors seem to care more about the CEP information for a firm than the CSP information.

The etiology of adenocarcinoma of the esophagogastric junction (AEG) remains unclear. It is believed that the increasing of AEG may be correlated with the elevated ratio of obesity and overweight. Thus, metabolism‐related genes and variants may play important roles in the occurrence and progress of AEG. The current investigation involved 720 patients with AEG and 1541 healthy controls. We selected transcription factor 7‐like 2 (TCF7L2) rs7903146 and rs290481, INS rs689 and INSR rs1799817 single‐nucleotide polymorphisms (SNPs), and explored the association of these SNPs with lymph node status and risk of AEG. The polymerase chain reaction was harnessed to identify the genotyping of four polymorphisms. We found that TCF7L2 rs290481 (T > C) and INSR rs1799817 (G > A) polymorphisms were associated with the increased susceptibility of AEG (P = .007 and 0.004 for TCF7L2 rs290481 in TC vs TT and TC/CC vs TT models, and P = .040 for INSR rs1799817 in GA/AA vs GG model). We also conducted a subgroup analysis by different cancer stage. We identified that TCF7L2 rs290481, INS rs689, and INSR rs1799817 SNPs increased the susceptibility of AEG in different cancer stage subgroups. In addition, we found that rs290481 SNP in TCF7L2 gene increased the risk of lymph node metastasis in drinking patients with AEG. However, the association of INSR rs1799817 SNP with a decreased risk of lymph node metastasis in smoking patients with AEG was found. Our findings highlight that TCF7L2 rs290481, INS rs689, and INSR rs1799817 polymorphisms may increase the risk of AEG. In addition, TCF7L2 rs290481 and INSR rs1799817 SNPs may influence the lymph node metastasis in patients with AEG.

Transactive response DNA-binding protein-43 (TDP-43) is involved in gene regulation via the control of RNA transcription, splicing, and transport. TDP-43 is a major protein component of ubiquinated...

The present study aimed to investigate the influence of different fractions of dissolved organic carbon (DOC) on the uptake and toxicity of nickel (Ni) in the soil invertebrate Enchytraeus crypticus after different exposure times. The addition of DOC as humic acid or fulvic acid significantly reduced Ni uptake by E. crypticus in the soil-solution test system. Median lethal effect concentrations were calculated based on total dissolved Ni concentrations (LC50[Ni]), free Ni ion activity (LC50{Ni2+ }), and Ni body concentrations (LC50Body-Ni ). The LC50[Ni] values increased with increasing DOC levels and decreased with exposure time (4, 7, and 10 d). Humic acid exerted a greater protective effect on Ni toxicity than fulvic acid, but the protective effects decreased with prolonged exposure time. The LC50{Ni2+ } values also decreased with exposure time but were almost constant with variation in DOC levels, indicating that the protective effect of DOC is mainly through complexation with free Ni ions to reduce Ni bioavailability. The LC50Body-Ni value was independent of DOC concentration and exposure time, with an estimated overall value of 22.1 µg/g dry weight. The present study shows that body concentration could serve as an effective indicator for predicting Ni toxicity with variations in the exposure environment (e.g., DOC) and exposure time. Environ Toxicol Chem 2017;36:3019-3027. © 2017 SETAC.

Zinc (Zn) and arsenic (As) are typically present as mixed contaminants in mining-impacted areas, however, their joined effects have rarely been evaluated. The present study was set-up to test if Zn2+ and H2AsO4- (further: As) mixture toxicity to plants is additive or if interactions occur. Barley (Hordeum vulgare) root elongation was measured in resin buffered nutrient solutions. The design included ranges of single element concentrations and combinations at three different Ca2+ concentrations (0.5, 2.2, and 15.0mM) to vary the relative toxicity of Zn2+. Increasing Ca concentrations decreased Zn toxicity, while As toxicity was unaffected by Ca. Root elongation was generally more affected in Zn-As mixtures than in corresponding single element treatments. This is merely a joint additive effect, since 96% of the root elongation data were within a factor 1.2 from predictions using the independent action (IA) or concentration addition (CA) model. The CA and IA predictions were similar and data did not allow to identify equal or dissimilar mode of action. Small, but significant Zn-As antagonisms were only found at high effects (>50% inhibition). The present study suggests that mixture effects of Zn and As are environmentally relevant and that current risk assessment underestimates toxicity in multi-element contaminated environments. The CA model can be used as a conservative model for risk assessment, however for soil grown plants, soil exposed studies are needed. This article is protected by copyright. All rights reserved

For the problem that the performance of existing multi-target tracking algorithm's serious degrades in a dense clutter environment, a novel Doppler information assistant δ-generalised labelled multi-Bernoulli (DI-δ-GLMB) filter is proposed. By introducing DI, a new measurement likelihood function is established, and the improved update equation based on the δ-GLMB filter framework is derived. In addition, a sequential Monte Carlo implementation method is given under the non-linear model. Simulation results show that compared with the DI probability hypothesis density filter and the standard δ-GLMB filter, the estimation of the proposed algorithm is more accurate and stable.

Background Polymorphisms in IL-17A and IL-23R may affect the expression of these genes and could contribute to a patient's susceptibility to coronary artery disease (CAD). Although this association was investigated by previous studies, the relationship remains unclear. Method We conducted this hospital-based case-control study to determine whether polymorphisms in these two genes could be associated with a risk of CAD. A total of 191 patients and 131 controls, as determined by SXscore, were enrolled in this study. The genotyping was performed with the Sequenom MassARRAY platform. Results The results showed that that the FPG and HbA1C levels were higher in patients with CAD than in the controls. In addition, the HDL and ApoA1 levels were significantly higher in the controls than in the cases. In contrast, the Lp(a) level was significantly lower in the controls than in the patients. The IL-17A rs2275913 and IL-23R rs6682925 polymorphisms were associated with an increased risk of CAD (rs2275913: AA vs GG: crude OR = 2.16, 95% CI = 1.08-4.30; AG/AA vs GG: crude OR = 1.81, 95% CI = 1.04-3.15; rs6682925 CC vs TT: crude OR = 1.91, 95% CI = 1.00-3.63). The subgroup analysis by SXscore revealed that the IL-23R rs6682925 polymorphism (CT/CC vs TT: crude OR = 3.72, 95% CI = 1.19-11.66) was associated with an increased risk of CAD in patients with a high SXscore. Conclusion This study suggested that T2DM, Lp(a), HDL-c, and ApoA1 were risk factors of CAD and that the IL-17A rs2275913 and IL-23R rs6682925 polymorphisms may contribute to susceptibility to CAD.

BACKGROUND Prostate cancer metastasis to bone is the second most commonly diagnosed malignant disease among men worldwide. Such metastatic disease is characterized by the presence of osteoblastic bone lesions, and is associated with high rates of mortality. However, the various mechanisms involved in prostate cancer-induced osteoblastic differentiation have not been fully explored. Semaphorin 3A (Sema 3A) is a newly identified regulator of bone metabolism which stimulates differentiation of pre-osteoblastic cells under physiological conditions. We investigated in this study whether prostate cancer cells can mediate osteoblastic activity through Sema 3A. METHODS We cultured osteoprogenitor MC3T3-E1 cells in prostate cancer-conditioned medium, and analyzed levels of Sema 3A protein in diverse prostate cancer cell lines to identify cell lines in which Sema 3A production showed a positive correlation with osteo-stimulation. C4–2 cells were stably transfected with Sema 3A short hairpin RNA to further determine whether Sema 3A contributes to the ability of C4–2 cells to induce osteoblastic differentiation. RESULTS Down-regulation of Sema 3A expression decreased indicators of C4–2 CM-induced osteoblastic differentiation, including alkaline phosphatase production and mineralization. Additionally, silencing or neutralizing Sema 3A in C4–2 cells resulted in diminished β-catenin expression in osteogenitor MC3T3-E1 cells. CONCLUSIONS Our results suggest that prostate cancer-induced osteoblastic differentiation is at least partially mediated by Sema 3A, and may be regulated by the β-catenin signalling pathway. Sema 3A may represent a novel target for treatment of prostate cancer-induced osteoblastic lesions. Prostate 75:370–380, 2015. © 2014 Wiley Periodicals, Inc.

The syntheses and characterization of the glycoluril, 1,5-diamino-3,7-dioxo-2,4,6,8-tetraazabicyclo[3.3.0]-octane (1), and a novel 3D infinite structure coordination polymer, [Na2(H2O)4(ITDO)2]n (ITDO = 2H-imidazo-[4,5-e]-as-1,2,4-triazine-2,7-dihydro-3,6-dione) (2) are described. Their crystal structures both belong to monoclinic space group P21/n. In the structure of 2 sodium is hexacoordinated by two types of both aqua ligands (monodentate and end-on bridge) and ITDO ligand (end-on bridge and end-to-end bridge). The ITDO ligand, which may have a potential application in anti-cancer therapy, is reported for the first time. Thermal analysis of 1 shows only one endothermic peak at 184.5 °C. Thermal analysis of 2 indicates two endothermic processes and three main successive exothermic processes occurred as shown in the DSC curve. The first endothermic peak temperature is 143.4 °C and the first exothermic peak temperature is 461.7 °C, which exhibits good thermal stability. Density functional theory calculations were performed for 2, which indicate that 2 is a kind of ionic complex and combined by electrostatic interaction. Moreover, the ITDO ligand is an active group in the chemical reactions of 2.

The use of the free ion approach to quantify the toxic effects of Cd and Ni to the earthworms Lumbricus rubellus and Aporrectodea longa exposed in soils of different types was explored. Median lethal concentration (LC50) of Cd (expressed as the total concentration in soil) varied by approximately 11-fold and 28-fold for L. rubellus and A. longa, respectively. For Ni, these values were 50-fold and 38-fold, respectively. For the 2 earthworm species, no significant influence of cations (H+, Ca2+, Mg2+, K+, and Na+) on Cd2+ toxicity was observed, while Mg2+ was found to significantly alleviate Ni2+ toxicity. The free ion activity model, which is a special case of the free ion approach with no impact of cations, sufficiently described the variability in Cd2+ toxicity across soils but failed in predicting Ni2+ toxicity. The free ion approach, in which the protective effects of Mg2+ were included, explained 89% and 84% of the variations in LC50{Ni2+} (expressed as free ion activity) for L. rubellus (log LC50{Ni2+} = 1.18log{Mg2+}−0.52) and A. longa (log LC50{Ni2+} = 0.51log{Mg2+}−2.16), respectively. Prediction error was within a factor of 2 for both Cd2+ and Ni2+ toxicity, indicating the applicability of the free ion approach for predicting toxicity of these 2 metals. Although extrapolation of the free ion approach across metals still needs more research efforts, this approach, as an alternative to the biotic ligand model, provides a feasible framework for site-specific risk assessment. Environ Toxicol Chem 2014;33:438–446. © 2013 SETAC

The formation of bacterial biofilm is one of the causes of antimicrobial resistance, often leading to persistent infections and a high fatality rate. Therefore, there is an urgent need to develop novel and effective strategies to inhibit biofilm formation. Adenosine triphosphate (ATP) plays an important role in bacterial adhesion and biofilm formation through stimulating cell lysis and extracellular DNA (eDNA) release. Herein, a simple and robust strategy for inhibiting biofilm formation is developed using CeO2 -decorated porphyrin-based metal-organic frameworks (MOFs). The function of extracellular ATP (eATP) can be inhibited by CeO2 nanoparticles, leading to the disruption of the initial adhesion of bacteria. Furthermore, planktonic bacteria can be killed by cytotoxic reactive oxygen species (ROS) generated by MOFs. As a consequence, the synergic effect of eATP deprivation and ROS generation presents excellent capacity to prevent biofilm formation, which may provide a new direction for designing flexible and effective biofilm-inhibiting systems.

An experimental study was performed for the boiling heat transfer enhancement of water/salt mixtures on both plane and roll-worked enhanced tubes in compact staggered tube-bundle evaporators under atmospheric and increased pressure conditions. The effects of tube spacing, position of tubes, test pressure and salt-water concentration on the boiling heat transfer characteristics in restricted spaces of compact tube bundles consisting of plane and roll-worked tubes were investigated. The experimental results indicate that the single roll-worked tubes in a bulk liquid have a greater boiling heat transfer promotion than the single plane tubes. For the plane tubes in compact tube bundles, the effect of tube spacing on the boiling heat transfer is very significant. The boiling heat transfer has a maximum enhancement when the optimum tube spacing is selected. For the roll-worked tubes in compact bundles, the effect of tube spacing on the boiling heat transfer is also significant as the tube spacing is small. The boiling heat transfer still has a maximum value and a compound enhancement effect of the boiling heat transfer from both the optimum tube spacing and the surface treatment is observed for the enhanced tube bundles.