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Hydrogen energy can be produced by the decomposition of hydrogen and carbon compounds. A numerical analysis method of accuracy and efficiency provides important reference value for optimizing development plans and predicting production performance of hydrogen and carbon compounds. In this work, embedded discrete fracture model (EDFM) is used to study the production performance of hydrogen and carbon compounds under non-liner seepage under the threshold pressure gradient and complex fracture systems consist of the hydraulic fractures, secondary fractures, natural fractures. A dual-permeability model of the same case is also constructed as a comparison study to analyze the development of hydrogen and carbon compounds. On this basis, the influence of threshold pressure gradient on production of hydrogen and carbon compounds is quantitatively evaluated in this paper to modify the numerical model and a novel method for the simulation of fractured hydrogen and carbon compounds reservoirs is provided. Through model comparison, the impact of fractures in the reservoir on production can reach 289.1%. A dual-permeability model of the same case is also constructed as a comparison study to analyze the development of the reservoir and the result shows a 7.9% distinction on the cumulative production. It is analyzed that when the threshold pressure gradient is increased from 0.1 MPa/m to 0.6 MPa/m, the output decline of different models ranges from 6% to 15% and a novel method improving model fidelity for the simulation of fracture reservoirs is provided. • A new numerical simulator was presented to study production performance in shale reservoirs. • Both embedded discrete fractures and the threshold pressure gradient were considered into model. • The method provides a new idea and reference for future horizontal well fracturing model. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a comprehensive semi-analytical model was presented to investigate pressure transient behavior for asymmetrically fractured wells in organic compound reservoir of hydrogen and carbon with dual-permeability behavior. Stehfest inversion algorithm can be used to transform it back into time domain to obtain pressure solution. The presented solution was validated well with numerical solutions. Flow characteristics for asymmetrically fractured wells in dual-permeability organic compound reservoir of hydrogen and carbon were divided into five regime. The effects of some important parameters on dimensionless pressure and its derivative curves were analyzed in details, including inter-porosity flow coefficient from matrix to natural fractures λ , storage coefficient ω , fracture asymmetry factor θ and permeability ratio κ. The presented model can be used to predict production performance and do well test analysis in the development of dual-permeability organic compound reservoir of hydrogen and carbon. Highlights • A dual-permeability model for asymmetrically fractured wells is presented. • The Lapalace-transform semi-analytical solution is developed. • The presented solution was validated through using numerical simulation. [ABSTRACT FROM AUTHOR]

Abstract The formation and temporal evolution of the modulated structure in a lamellar γ-based Ti−45Al−8.5Nb alloy have been investigated by transmission electron microscopy (TEM) in combination with first-principles theory in this work. The results show that the Nb-rich O phase as a constituent of the modulated structure is thermodynamically stable below 650 °C in the α 2 lamellae. The morphology of the O phase variants changes from thin plate-like shape with a low volume fraction at initial annealing to rectangle/square shape with a high volume fraction after a prolonged annealing, and the retransformed α 2 , named as α 2 - ІІ hereafter, emerges at intersections of the variants with two orthogonal habit planes due to their elastic interactions. The partitioning coefficient of Nb between the O phase and α 2 is about 2 at 600 °C. The diffusion coefficient of Nb derived from growth kinetics of the O phase is about (1.3 ± 0.2) × 10−22 m2s−1 in the α 2 lamellae. Significant precipitation hardening effect of the O phase has been revealed for the α 2 lamellae and γ/(α 2 +O) lamellar microstructure, which is supposed to be attributed to refining the α 2 lamellae associated with elastic strain energy from the α 2 →O phase transformation and introducing the interface between the modulated lamella and adjacent γ phase. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract A simulation approach using the embedded discrete fracture method (EDFM) is proposed to predict the productions of multistage hydraulic fractured horizontal wells(MHFHWs)in Fuling Shale gas field in China. The approach is divided into four stages: 1) geological structure model; 2) characterize the geometry details of hydraulic and natural fractures with micro-seismic data and embedment of the fractures into structured background grids; 3) adjust the properties of effective fractures as well as other uncertain parameters by history-matching; 4) predict and analyze the performance. The proposed approach is implemented to a real case with three MHFHWs and contributes to determine the next development strategy. Highlights • Microseismic data is used to determine the hydraulic fractures distribution. • Embedded discrete fracture method (EDFM) is applied to simulate the flow in fracture network. • Component subdivision method is applied to analyze the composition of total production. • Impact factors on well performance during shale gas development are investigated in this study. [ABSTRACT FROM AUTHOR]

The diffraction pattern of a material contains information not only on the crystal structures of its constituting phases, but also on its mesoscale spatial distributions of phases, grains, and ferroelastic, ferroelectric, and ferromagnetic domains. While diffraction patterns from experiments such as X-ray diffraction are presented in the reciprocal or Fourier space, mesoscale microstructure models such as the phase-field method naturally produce real-space images of spatial distribution of chemical composition, structural, and ferroic domains. Although one could rather readily compute the Fourier amplitudes of chemical and structural domain distributions generated by mesoscale simulations, they only contain information about the length scale and alignment of the real-space chemical and structure domains. Therefore, a direct comparison between diffraction experiments and mesoscale microstructure simulations is not possible. Here, we develop a theoretical approach to directly compute the crystal diffraction patterns of microstructures predicted by phase-field simulations. In particular, we consider five representative examples of microstructure patterns involving purely compositional domains, a single pair of tetragonal twin structures, multiple twin variants in a hexagonal system, ferroelectric polar vortices, and polycrystalline grains. The results are compared with previous experimental observations as well as X-ray diffraction experiments performed in the present study. The theoretical framework allows one to directly connect material microstructures and diffraction patterns predicted from phase-field simulations and the corresponding diffraction patterns from experiments, and thus providing guidance to experimental diffraction characterization and interpretation of microstructures. [Display omitted] [ABSTRACT FROM AUTHOR]

Cardiac remodelling mainly manifests as excessive myocardial hypertrophy and fibrosis, which are associated with heart failure. Gentianella acuta (G. acuta) is reportedly effective in cardiac protection; however, the mechanism by which it protects against cardiac remodelling is not fully understood. Here, we discuss the effects and mechanisms of G. acuta in transverse aortic constriction (TAC)-induced cardiac remodelling in rats. Cardiac function was analysed using echocardiography and electrocardiography. Haematoxylin and eosin, Masson′s trichrome, and wheat germ agglutinin staining were used to observe pathophysiological changes. Additionally, real-time quantitative reverse transcription polymerase chain reaction and western blotting were used to measure protein levels and mRNA levels of genes related to myocardial hypertrophy and fibrosis. Immunofluorescence double staining was used to investigate the co-expression of endothelial and interstitial markers. Western blotting was used to estimate the expression and phosphorylation levels of the regulatory proteins involved in autophagy and endothelial-mesenchymal transition (EndMT). The results showed that G. acuta alleviated cardiac dysfunction and remodelling. The elevated levels of myocardial hypertrophy and fibrosis markers, induced by TAC, decreased significantly after G. acuta intervention. G. acuta decreased the expression of LC3 II and Beclin1, and increased p62 expression. G. acuta upregulated the expression of CD31 and vascular endothelial-cadherin, and prevented the expression of α-smooth muscle actin and vimentin. Furthermore, G. acuta inhibited the PI3K/Akt/FOXO1/3a pathway and activated the Notch signalling. These findings demonstrated that G. acuta has cardioprotective effects, such as alleviating myocardial fibrosis, inhibiting hypertrophy, reducing autophagy, and blocking EndMT by regulating the PI3K/Akt/FOXO1/3a and Notch signalling pathways. [Display omitted] • Gentianella acuta attenuates pressure overload-induced cardiac dysfunction in rats. • Gentianella acuta ameliorates pressure overload-induced heart hypertrophy and fibrosis. • Gentianella acuta improves ventricular remodelling by inhibiting autophagy and EndMT. • Gentianella acuta protects the heart by regulating Notch and PI3K/Akt/FOXO1/3 pathway. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study was to discuss the risk factors of postoperative limb overgrowth after the application of titanium elastic nailing (TEN) in the treatment of pediatric femoral fractures as well as analyze the causes and provide guidance for clinical treatment.Methods: The study included children with femoral fractures who were treated with TEN at our hospital from February 2005 to December 2009. Their age, gender, weight, cause of injury, having head trauma or not, fracture site, fracture type and nail-canal diameter (NCD) ratio were recorded. Student's t-test, chi-square test or Fisher's exact test was used for univariate analysis of the above factors, and then multivariate logistic regression analysis was used to analyze the possible risk factors in order to determine which ones are associated with limb overgrowth after the application of TEN to treat children with femoral fractures.Results: Univariate analysis showed that the age, gender, weight, cause of injury, having head trauma or not, and the fracture site did not have a statistically significant association with limb overgrowth (P = 0.741, 0.900, 0.253, 0.739, 0.967 and 0.105, respectively). The fracture type and NCD ratio were significantly associated with limb overgrowth (P = 0.003 and 0.000, respectively). Multivariate logistic regression analysis demonstrated that the fracture type (P = 0.021, OR = 2.757) and NCD ratio (P = 0.002, OR = 2.422) were independent risk factors for limb overgrowth.Conclusions: The main factors affecting postoperative limb overgrowth are the fracture type and NCD ratio. In order to avoid limb overgrowth, unstable fractures should be fixed as firmly as possible, and the NCD ratio should be ≥0.8. [ABSTRACT FROM AUTHOR]

This paper reports an experimental and theoretical study of composition and temperature dependence of α 2 phase decomposition in lamellar γ-Ti−(43∼47)Al−(4∼10)Nb alloys. The α 2 phase decomposes to nano-sized orthorhombic (O) phase in the alloys (the Nb content ≥ 5.5 at.%) at temperatures of 550∼750° C. The transformation temperature decreases with increasing the Al content, but increases with increasing the Nb content. The Nb partitioning coefficient between O and α 2 typically equals to 2, and decreases with increasing the Al content and temperature, confirming that the O phase transformation is controlled by Nb diffusion. The α 2 to ω 0 phase transformation takes place in the alloys (the Nb content ≥ 7 at.%) at 800° C. The blocky ω 0 phase is enriched in Nb and the Nb partitioning coefficient between ω 0 and α 2 is about 1.3, indicating that the ω 0 phase transformation is also related to Nb diffusion. The pseudo-binary phase diagram calculated by first-principles correctly predicts the α 2 to O phase transformation at temperature below 750° C and α 2 to ω 0 phase transformation at temperature above 750° C in the alloys. Since the α 2 phase is unstable thermodynamically at intermediate temperature, such kinds of α 2 to O and ω 0 phase transformations are considered necessarily for design of high Nb-containing γ-TiAl alloys. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Activated mTOR was implicated to play a role in the carcinogenesis of nasopharyngeal carcinoma (NPC). However, the mechanism of activated mTOR/Complex1(mTORC1) signaling pathway in NPC development has not been well established. In this study, we correlated the expression of mTORC1 signal molecules and Cyclin D1 in NPC. We also investigated the effect of blocking mTORC1 signal with rapamycin and mTOR siRNA on Cyclin D1 expression in CNE-2 cells, as well as cell apoptosis and viability. We found a positive association of mTORC1 signal molecules and Cyclin D1 in NPC. Also, we found blockage mTORC1 inhibited Cyclin D1 expression in CNE-2 cells and enhanced cell apoptosis. Our results suggested that mTORC1 signal pathway might be a potential target for NPC therapy. [Copyright &y& Elsevier]

Generalized gradient approximation with on-site Coulomb corrections (GGA+ U ) method is used to investigate the effect of biaxial strain on the Néel temperature of SrTcO 3 . A series of hypothetical strains on SrTcO 3 are considered to simulate its being applied in SrTcO 3 -based devices. It is found that a tensile strain will decrease T N , while a compressive strain less than 6.6% will increase T N . At a compressive strain between 5.5% and 6.7%, a highest T N which is about 26.6% higher than that of the bulk material can be obtained. The higher T N can be experimentally achieved by growing SrTcO 3 on the common substrate STO/LSAT/NGO/LAO. Our work provides a theoretical basis for the application of high- T N SrTcO 3 in small devices. [ABSTRACT FROM AUTHOR]

• The optimal plastic content for MSW is 6–9 %. • Stress path influences the optimal plastic content. • The influence patterns of particle size distribution on MSW. • Traditional well-graded criteria are unsuitable for MSW. Plastics within municipal solid waste (MSW) are non-degradable. As MSW continues to degrade, the relative content of plastics rises, and particle gradation may also change. Moreover, throughout the landfilling process, MSW is subjected to various stress conditions, potentially influencing its mechanical properties. This study explored the effects of varying plastic contents, different particle gradations, and distinct stress paths on the mechanical properties of MSW, and consolidated drained triaxial tests of 42 groups of reconstituted MSW specimens were conducted. The results showed that there was an optimal plastic content of 6–9 % for MSW, where the shear strength of MSW was higher than that of MSW with other plastic contents. When the stress path changed from TC45 to TC72, the optimal plastic content of MSW changed from 6 % to 9 %. As the plastic content increased, both the cohesion and internal friction angle of the MSW initially increased, then subsequently decreased. The impact of plastic content on cohesion was more pronounced than on the internal friction angle, especially at larger strains. Under various stress paths, MSW with distinct particle size distributions demonstrated diverse stress–strain behaviors. Traditional criteria for evaluating well-graded conditions in soils are not suitable for MSW. The effect of gradation on the cohesion of MSW is essentially due to the predominant role of fiber content; the relationship between gradation and the internal friction angle in MSW is complex and correlates closely with the content of both coarse and fine particles, as well as fibers. This study serves as an essential reference for predicting deformations in landfills and analyzing the stability of landfill slopes. [ABSTRACT FROM AUTHOR]

To increase the specific energy of supercapacitors (SCs), the expanded mesocarbon microbead (EMCMB) is electrochemically activated in 1 M tetraethylammonium tetrafluoroborate in propylene carbonate (TEABF 4 /PC) to construct a high-voltage but symmetric SC. The EMCMB is successfully made from MCMB through the oxidation in a solution containing concentrated H 2 SO 4 , HNO 3 and KMnO 4 followed by a thermo-expansion treatment at 800°C. This carbon with a specific surface area of only 93.2 m2 g−1 shows excellent capacitive performance after the electrochemical activation process in the highly positive or very negative potential regions in 1 M TEABF 4 /PC, especially when an aqueous-based binder, KOH-partially-neutralized polyurethane-polyacrylic acid (denoted as PUPAH 6 K 4) was employed. These electrochemically activated EMCMB-PUPAH 6 K 4 electrodes are able to be charged and discharged reversibly in a wide potential range between −2.6 V and 1.4 V (vs. Ag/AgNO 3). Consequently, a 4V SC consisting of two identical EMCMB-coated electrodes, i.e., symmetric, with good capacitive performances in 1 M TEABF 4 /PC has been successfully demonstrated, showing the great application potential in the advanced high-voltage SCs. [ABSTRACT FROM AUTHOR]

Background External fixation combined with limited open reduction and internal fixation (EF + LORIF) is a well-accepted and effective method for distal tibia shaft fractures, but it was also related to complications. The objective of this study was to compare external fixation combined with closed reduction and internal fixation (EF + CRIF) with EF + LORIF in the treatment of distal tibia shaft fractures, and explore the benefits and defects of these two techniques. Methods Fifty-six patients were randomised to operative stabilisation either by an external fixator combined with two closed titanium elastic nails or by external fixation combined with limited open reduction and internal fixation. Pre-operative variables included the patients’ age, sex, the affected side, cause of injury, Tscherne classification of soft tissue injury, fracture pattern, and time from injury to surgery. Peri-operative variables were the operating time and the radiation time. Postoperative variables were wound problems and other complications, union time, time of recovery to work, the functional American Orthopaedic Foot and Ankle surgery (AOFAS) score. Results There was no significant difference in the mean operating time (72.6 ± 11.5 vs. 78.5 ± 16.4 min, P = 0.125), the time to union (21.2 ± 11.0 vs. 22.5 ± 12.3 weeks, P = 0.678), the time of recovery to work (25.0 ± 14.5 vs. 26.4 ± 13.6 weeks, P = 0.711), pin track infection (3/28 vs. 4/28, P = 1.000), delayed union (2/28 vs. 3/28, P = 1.000), pain (38.3 ± 1.6 vs. 38.7 ± 1.5, P = 0.339), function (44.4 ± 6.0 vs. 45.0 ± 5.5, P = 0.698), and total AOFAS scores (91.5 ± 7.4 vs. 93.4 ± 6.8, P = 0.322) between the two groups. However, the mean radiation time was longer in the EF + CRIF group than in the EF + LORIF group (2.0 ± 1.2 vs. 0.3 ± 0.1 min, P < 0.01). The EF + CRIF group had no wound complications while the EF + LORIF group had five wound complications, though the difference was not statistically significant ( P = 0.052). Acceptable alignment was obtained in 50 patients (22 in EF + CRIF vs. 28 in EF + LORIF, P = 0.023). Two cases with EF + CRIF had a 6 degrees of recurvatum deformity and four had 6–9 degrees of valgus deformity. Conclusion Our results indicated that both EF + CRIF and EF + LORIF were reliable methods in treatment of distal tibia shaft fractures. EF + CRIF had fewer wound complications and broader indications while EF + LORIF had lower radiation exposure and better alignment. [ABSTRACT FROM AUTHOR]

Fused deposition of ceramics (FDC) is one of the developing solid freeform fabrication (SFF) techniques. The successful production of high performance ceramics by the FDC process requires that no defects exist in the green parts. However, build defects, such as missing roads, poorly bonded layers or sub-perimeter voids can be encountered in improperly built FDC parts. In this study, a method known as WIP''ing (warm isostatic pressing) was evaluated for its ability to eliminate existing defects in GS44 Si3N4 green FDC parts. Analogous to CIP''ing (cold isostatic pressing), the green FDC parts were rubber bagged and loaded into a pressure chamber filled with water soluble oil at different temperatures, ranging from 30 to 90°C, at pressures of up to 35 MPa. X-Ray radiography results indicated that at temperatures above 70°C, WIP''ing was effective in closing the gaps of the intentionally placed void defects in FDC parts. However, WIP''ing above 70°C was not effective in healing the defects completely. The fracture strengths of FDC parts with intentional added defects, WIP''ed above 70°C were substantially lower than control samples. [Copyright &y& Elsevier]

• Perpendicular magnetic anisotropy was enhanced by B 4 C capping layer. • Out-of-plane coercivity was increased by B 4 C capping layer. • Ordering degree and surface roughness were improved by B 4 C capping layer. • The B, C, N elements were segregated in FePt grains and boundaries. The in-plane magnetic component in FePt-40 vol% (Ag, C) granular film was caused by lower ordering degree which lower the magnetic anisotropy field and out-of-plane coercivity (H c = 23.6 kOe). To inhibit the FePt grains with second nucleation, random texture and in plane c-axis, the ultrathin B 4 C layer with thickness of 1 nm was capped. After surface modification, the FePt-40 vol% (Ag, C) film illustrates high perpendicular magnetic anisotropy (K u = 1.75 × 107 erg/cm3) and out-of-plane coercivity (H c = 28.8 kOe). The in-plane remanence magnetic moment is small and the tiny magnetization kink at zero field was not observed in easy-axis loop of 6 nm thick FePt-40 vol% (Ag, C) film. The ordering degree and the average surface roughness of FePt-(Ag, C) films were improved by surface diffusion of B 4 C which deposited at 470 °C and post-annealed for 2 min. Further, the perpendicular magnetic anisotropy and out-of-plane coercivity of FePt-(Ag, C) films were enhanced significantly. The TiO x are more favorable than TiN in MgTiON layer due to formation enthalpy, part of N atoms was diffused and incorporated in the FePt lattice evidenced in high angle angular dark field mapping. After post annealing, the released N atoms cause lots of vacancies and defects inside FePt film which promote the ordering degree. [ABSTRACT FROM AUTHOR]

Metastasis is the leading cause of deaths in patients with breast cancer. Benzo[a]pyrene is a cumulative carcinogen and ubiquitous environmental pollutant with potent carcinogenic properties. As we report here, we established an accumulative mouse model mimicking the cumulative effects of benzo[a]pyrene exposure in human breast carcinogenesis. Our focus was on elucidating the mechanisms by which benzo[a]pyrene contributes to the process of breast cancer metastasis. Our study indicated that benzo[a]pyrene increased the migration of breast cancer cells both in vitro and in vivo . Specifically, we demonstrated that benzo[a]pyrene enhances breast cancer cell migration and invasion by up-regulating ROS-induced ERK signaling, leading to the activation of matrix metalloproteinases 9. Our results suggest that benzo[a]pyrene-induced mammary gland cancer metastasis is an important and intricate process facilitated by cumulative benzo[a]pyrene exposure leading to activation of the ROS-ERK-MMP9 signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: The mean-field potential (MFP) approach is an efficient way to evaluate the free energy contribution of ion motions for both solid and liquid states. In this paper the MFP is generally constructed with a volume-dependent term and a shape function. The former is derived in accordance with quasi-harmonic approximation. The latter is given semi-empirically. Application to multiphase equations of state for β-, γ- and liquid-tin has been examined. The theoretical phase diagram and thermodynamic properties of isotherm, thermal expansion, heat capacity, Hugoniot states as well as phase transitions are all in excellent agreement with experiments. [Copyright &y& Elsevier]

CO 2 and CH 4 are the two most potent greenhouse gases (GHGs) in the atmosphere. They are frequently monitored at background observatories, but less so in urban areas, especially in China. In this study, the temporal variations of urban atmospheric CO 2 and CH 4 , including seasonal, weekly, and diurnal characteristics, were obtained based on one year of continuous measurement in the megacity Shanghai. Probable anthropogenic sources were further investigated through relationships among GHGs and atmospheric pollutants. Potential sources regions and transport pathways of GHGs were studied in association with meteorological conditions. The annual average concentrations of CO 2 and CH 4 were 428.36 ± 13.96 ppm and 2154 ± 190 ppb, respectively, which were higher than those at global and regional background observatories. The highest CO 2 concentration appeared in winter and the lowest in autumn, whereas CH 4 values were highest in summer and lowest in spring. Both CO 2 and CH 4 showed strong diurnal variations, but only CO 2 exhibited seasonal and weekly differences due to the variation of emission sources and plant photosynthesis in Shanghai and the surrounding Yangtze River Delta (YRD). CO 2 and combustion-derived air pollutants were co-emitted from similar sources and co-transported to the research site, as demonstrated by correlation analysis. Furthermore, the correlation analysis also suggested some neglected anthropogenic combustion sources of CH 4 in Shanghai, besides the traditional biogenic emissions from landfills, wetlands, paddy fields, and dairy farms. The anthropogenic CO 2 concentration in urban Shanghai estimated from a CO 2 -CO regression model was 14.98 ± 5.09 ppm, together with a background concentration of 413.31 ± 7.07 ppm, which was higher than at global background sites but lower than at the nearby regional background Lin'an station. GHGs were accumulated from local sources under stable weather conditions and transported from remote sources at high wind speeds. Air masses from "super-emitters" north and south of the observation site contributed most of the elevation in GHGs concentration above their annual averages. Considering the co-emissions of GHGs and air pollutants from carbon-containing material combustion and use, and the potential of methane to generate O 3 in the urban environment, reduction of CO 2 and CH 4 together with air pollutants could benefit both climate and air quality in Shanghai and the surrounding YRD. Unlabelled Image • CO 2 and CH 4 were measured together with air pollutants and meteorological conditions in urban Shanghai. • Both CO 2 and CH 4 showed diurnal variations, but only CO 2 showed seasonal and weekday effects. • Anthropogenic sources affected the elevated concentrations of GHGs in urban environment. • GHGs were accumulated from local sources in stable, together with transport from remote sources. • Joint control of GHGs and air pollutants could benefit both climate and air quality. [ABSTRACT FROM AUTHOR]