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Various mechanisms are employed to interpret the low water recovery during the shale-gas production period, such as extra-trapped water in the fracture network, water imbibition due to osmotic pressure and capillary pressure. These lead to the difficulty of water flow, which could be described by low-velocity non-Darcy's law known as threshold pressure gradient (TPG). In this paper we firstly employ the low-velocity non-Darcy's law to describe the water flow and use Darcy flow accounting for slip flow and free molecular flow mechanisms to model gas flow in the shale formation. The sensitive study using numerical simulation shows that the proposed flow model could model the low fracturing liquid recovery and that large pseudo TPG leads to lower fracturing liquid recovery. Thus, the proposed model would give new insight to model the low water recovery in shale formations.

Abstract: An automatic well test interpretation method for radial composite reservoirs based on convolutional neural network (CNN) is proposed, and its effectiveness and accuracy are verified by actual field data. In this paper, based on the data transformed by logarithm function and the loss function of mean square error (MSE), the optimal CNN is obtained by reducing the loss function to optimize the network with “dropout” method to avoid over fitting. The trained optimal network can be directly used to interpret the buildup or drawdown pressure data of the well in the radial composite reservoir, that is, the log-log plot of the given measured pressure variation and its derivative data are input into the network, the outputs are corresponding reservoir parameters (mobility ratio, storativity ratio, dimensionless composite radius, and dimensionless group characterizing well storage and skin effects), which realizes the automatic initial fitting of well test interpretation parameters. The method is verified with field measured data of Daqing Oilfield. The research shows that the method has high interpretation accuracy, and it is superior to the analytical method and the least square method.

A mathematical dual porosity and dual permeability numerical model based on perpendicular bisection (PEBI) grid is developed to describe gas flow behaviors in shale-gas reservoirs by incorporating slippage corrected permeability and adsorbed gas effect. Parametric studies are conducted for a horizontal well with multiple infinite conductivity hydraulic fractures in shale-gas reservoir to investigate effect of matrix-wellbore flow, natural fracture porosity, and matrix porosity. We find that the ratio of fracture permeability to matrix permeability approximately decides the bottom hole pressure (BHP) error caused by omitting the flow between matrix and wellbore and that the effect of matrix porosity on BHP is related to adsorption gas content. When adsorbed gas accounts for large proportion of the total gas storage in shale formation, matrix porosity only has a very small effect on BHP. Otherwise, it has obvious influence. This paper can help us understand the complex pressure transient response due to existence of the adsorbed gas and help petroleum engineers to interpret the field data better.

Abstract A fungal effector that is toxic to plant cells was identified in Verticillium dahliae. The effector contains a non-canonical Common in several Fungal Extracellular Membrane proteins (CFEM) domain, a tandem repeat region consisting of four 14-amino acid repeats rich in proline, and a C-terminal region, thus is designated V. dahliae tetrapeptide repeat protein (VdTRP). The membrane targeting of VdTRP is vital for its cell toxicity. CFEM mediates the membrane targeting and the tandem repeat region exerts the toxic function upon cell membrane. The chitinase-like 1 (CTL1), an essential apoplastic protein of cotton, can redirect VdTRP from cell membrane to apoplast. Transgenic cotton overexpressing CTL1 greatly enhances cotton resistance to V. dahliae without affecting cotton growth and development, implicating its potential application in breeding cotton with high wilt resistance. Our data demonstrates that genetic manipulation of effector target constitutes potential strategy for improving crop resistance to fungal pathogens.

Abstract The rapid and repeatable characterization of individual morphology has advanced automated taxonomic classification. The most direct study of evolutionary processes is, however, not from taxonomic description, but rather of the evolution of the traits that comprise individuals and define species. Repeatable signatures of individual morphology are crucial for analysing the response to selection at scale, and thus tracking evolutionary trajectories through time and across species boundaries. Here, we introduce our 3DKMI—an open‐source MATLAB package designed for the study of morphology using three‐dimensional (3D) Krawtchouk moment invariants. The volumetric features derived from the 3D images remain stable under translation, scaling and rotation and, for an image of size 128 × 128 × 128 can be computed in less than 0.1 s. We applied our package as a case study on a collection of 300 X‐ray computed tomography scans of planktonic foraminifera specimens across five species to (1) assess the invariance of the features under different transformations and (2) analyse morphological differences among species based on the extracted characteristics. We show that 3DKMI has the capacity to efficiently and repeatedly characterize the signatures of individual morphology. In the future, we hope that the 3D feature extraction technique 3DKMI will be widely applied to digital collections to advance research in ecology and evolution.

The present study focuses on investigating the low cycle fatigue (LCF) behavior and cyclic deformation mechanism of Ti–6Al–4V-0.55Fe alloy under strain and stress control. Based on the results of this alloy under strain amplitudes and the corresponding stress amplitudes, the effect of tension-compression asymmetry (TCA) on fatigue behavior and microstructure evolution was systematically discussed with transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD). The results show that under strain control, TCA has little effect on LCF behavior due to the negligible compressive mean stress. And the deformation mechanism is mainly determined by planar slip. While under stress control, the accumulation of significant unidirectional ratcheting strain caused by TCA is observed, resulting in extra heterogeneous plastic deformation and more fatigue damage, responsible for the reduction in fatigue life. However, under low stress amplitude (≤690 MPa), no ratcheting behavior occurs due to the constant strain amplitude (0.56%), which reduces the driving force of crack nucleation and prolongs fatigue life, compared with that under low strain amplitude (0.6%).

The preparation of dense Si3N4-based ceramics has attracted great attention because of the achievable improvements in their mechanical properties and high-temperature oxidation resistance. In this work, advanced dense boron-containing α/β-Si3N4/Si monoliths were prepared via a high pressure‒high temperature technique in which polymer-derived amorphous SiBN powders were used as raw materials. The crystallization behavior and phase transformation of the polymer-derived amorphous samples were studied in the temperature range from 1400 to 1800 °C. The results demonstrate that the incorporation of boron in the Si3N4 matrix suppresses the phase transformation from α-Si3N4 to β-Si3N4. Furthermore, the mechanical properties of the as-prepared samples were measured, and the maximum hardness and fracture toughness of boron-rich SiBN samples reached 14.8 GPa and 7.96 MPa·m1/2, respectively. The hardness of the obtained boron-rich SiBN samples is stable up to 300 °C. In addition, the oxidation behavior of the samples prepared at 1400 and 1600 °C was investigated at 1400 °C for 50 h. The results show that the incorporation of boron significantly improved the oxidation resistance of the samples because of the formation of borosilicate/cristobalite. This work provides guidance for the synthesis of boron-containing α/β-Si3N4-based ceramics with excellent mechanical properties and oxidation resistance.

Abstract Background Although previous observational studies have shown an association between venous thromboembolism (VTE) and atrial fibrillation (AF), the underlying causal relationship between them remains uncertain. Methods and results This two-sample bidirectional Mendelian randomization (MR) analysis was performed to investigate the causal relationship between VTE and AF. The VTE dataset were obtained from FinnGen, including 9,176 cases and 209,616 controls. Meanwhile a genome-wide association study (GWAS) of 60,620 individuals with AF and 970,216 control subjects identified genetic variations associated with AF. The principal MR analytic approach used in this study is the inverse-variance weighting (IVW) method. Furthermore, we performed complementary MR analyses, including the MR-Egger, Weighted median (WM), and Weighted Mode. MR pleiotropy residual sum was applied to identify pleiotropy. The MR analysis showed suggestive causal associations between VTE and the risk of AF (p = 0.0245, OR [95%CI]: 1.027 [1.003, 1.051]). The reverse MR analysis found that genetic susceptibility to AF was not significantly associated with VTE, as determined by the IVW method (p = 0.7773). The robustness of these findings was corroborated through MR sensitivity analyses. Conclusions There is a unidirectional causal relationship between VTE and AF, meaning that VTE is a causal risk factor for AF, whereas no effect of AF on VTE was identified.

Background: Iron overload is considered an unfavorable prognosis in myelodysplastic syndrome (MDS) even in those undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). Although iron chelation therapy has improved the prognosis of these patients to some extent, the effect has not yet been satisfactory. Objectives: This study aimed to investigate the impact of granulocyte colony-stimulating factor and decitabine (G-DAC)-containing conditioning in iron-overloaded MDS patients undergoing allo-HSCT. Design: This was a retrospective study. Methods: One hundred and ninety-seven patients were enrolled in this retrospective study. Based on the level of serum ferritin (SF) and conditioning regimen, all patients enrolled were divided into four groups: SF

Anti-infection strategies against pleural empyema include the use of antibiotics and drainage treatments, but bacterial eradication rates remain low. A major challenge is the formation of biofilms in the pleural cavity. DNase has antibiofilm efficacy in vitro, and intrapleural therapy with DNase is recommended to treat pleural empyema, but the relevant mechanisms remain limited. Our aim was to investigate whether DNase I inhibit the early biofilm formation in Pseudomonas aeruginosa- or Staphylococcus aureus-induced empyema models. We used various assays, such as crystal violet staining, confocal laser scanning microscopy (CLSM) analysis, peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH), and scanning electron microscopy (SEM) analysis. Our results suggested that DNase I significantly inhibited early biofilm formation in a dose-dependent manner, without affecting the growth of P. aeruginosa or S. aureus in vitro. CLSM analysis confirmed that DNase I decreased the biomass and thickness of both bacterial biofilms. The PNA-FISH and SEM analyses also revealed that DNase I inhibited early (24h) biofilm formation in two empyema models. Thus, the results indicated that DNase inhibited early (24h) biofilm formation in P. aeruginosa- or S. aureus-induced rabbit empyema models and showed its therapeutic potential against empyema biofilms.

Abstract In the present study, the use of a 3 wt% Fe2O3 catalyst improved the crystallisation of polysilazane PSN2. Crystallisation peaks of higher intensity were observed for Si3N4 and SiC at 1250 °C by using a 3 wt% Fe2O3 catalyst than at 1500 °C without Fe2O3. Besides, the effects of temperature on the morphology of the samples were determined through scanning electron microscopy. Porous structures were observed at 1250 °C and these structures were transformed to flaky and near‐spherical nanoparticles as the temperatures were increased to 1350 and 1450 °C, respectively. Finally, the mechanism of Fe origination from Fe2O3 reduction, the production of a supersaturated liquid alloy, and the release and diffusion of N2 were proposed for Si3N4 formation.

Abstract 2D MXenes are attractive for energy storage applications because of their high electronic conductivity. However, it is still highly challenging for improving the sluggish sodium (Na)-ion transport kinetics within the MXenes interlayers. Herein, a novel nitrogen-doped Ti3C2T x MXene was synthesized by introducing the in situ polymeric sodium dicyanamide (Na-dca) to tune the complex terminations and then utilized as intercalation-type pseudocapacitive anode of Na-ion capacitors (NICs). The Na-dca can intercalate into the interlayers of Ti3C2T x nanosheets and simultaneously form sodium tricyanomelaminate (Na3TCM) by the catalyst-free trimerization. The as-prepared Ti3C2T x /Na3TCM exhibits a high N-doping of 5.6 at.% in the form of strong Ti–N bonding and stabilized triazine ring structure. Consequently, coupling Ti3C2T x /Na3TCM anode with different mass of activated carbon cathodes, the asymmetric MXene//carbon NICs are assembled. It is able to deliver high energy density (97.6 Wh kg−1), high power output (16.5 kW kg−1), and excellent cycling stability (≈ 82.6% capacitance retention after 8000 cycles).

Identification of the offending organism and appropriate antimicrobial therapy are crucial for treating empyema. Diagnosis of empyema is largely obscured by the conventional bacterial cultivation and PCR process that has relatively low sensitivity, leading to limited understanding of the etiopathogenesis, microbiology, and role of antibiotics in the pleural cavity. To expand our understanding of its pathophysiology, we have carried out a metagenomic snapshot of the pleural effusion from 45 empyema patients by Illumina sequencing platform to assess its taxonomic, and antibiotic resistome structure. Our results showed that the variation of microbiota in the pleural effusion is generally stratified, not continuous. There are two distinct microbiome clusters observed in the forty-five samples: HA-SA type and LA-SA type. The categorization is mostly driven by species composition: HA-SA type is marked by Staphylococcus aureus as the core species, with other enriched 6 bacteria and 3 fungi, forming a low diversity and highly stable microbial community; whereas the LA-SA type has a more diverse microbial community with a distinct set of bacterial species that are assumed to be the oral origin. The microbial community does not shape the dominant antibiotic resistance classes which were common in the two types, while the increase of microbial diversity was correlated with the increase in antibiotic resistance genes. The existence of well-balanced microbial symbiotic states might respond differently to pathogen colonization and drug intake. This study provides a deeper understanding of the pathobiology of pleural empyema and suggests that potential resistance genes may hinder the antimicrobial therapy of empyema.

It is a well-documented event that fibroblast growth factors (FGFs) regulate liver development and homeostasis in autocrine, paracrine, and endocrine manners via binding and activating FGF receptors (FGFRs) tyrosine kinase in hepatocytes. Recent research reveals that hepatic stellate cells (HSCs) play a fundamental role in liver immunology. However, how FGF signaling in HSCs regulates liver inflammation remains unclear. Here, we report that FGF promoted NF-κB signaling, an inflammatory pathway, in human HSCs, which was associated with FGFR1 expression. Both FGF and NF-κB signaling in HSCs were compromised by FGFR1 tyrosine kinase inhibitor. After stimulating HSCs with proinflammatory cytokines, expression of multiple FGF ligands was significantly increased. However, disruption of FGF signaling with FGFR inhibitors prominently reduced the apoptosis, inflammatory response, NF-κB nuclear translocation, and expression of matrix metalloproteinase-9 (MMP-9) induced by TNFα in HSCs. Interestingly, FGF21 significantly alleviated the inflammation responses in the concanavalin A (Con A)-induced acutely injured liver. Unlike canonic FGFs that elicit signals through activating the FGFR–heparan sulfate complex, FGF21 activates the FGFR–KLB complex and elicits a different set of signals. Therefore, the finding here indicates the urgency of developing pathway-specific inhibitors that only suppress canonical FGF, but not non-canonical FGF21, signaling for alleviating inflammation in the liver, which is presented in all stages of diseased liver.

High temperature resistant coating is becoming a key technique to improve the heat resistance of aerospace heat-resistant components. In this paper, Ti6Al4V/Inconel625 gradient coating was fabricated by laser melting deposition. The results show that the microstructure changes with composition gradient, from lamellar structure consisting of lamellar α and β phases to equiaxed structure. With the increase of the proportion for nickel-based alloy, alloying elements and concentration of solute increase in molten pool. Furthermore, the nucleation rate increases due to the increase of alloying elements, which leads to the microstructure refinement. The phase composition of gradient coating changes in the sequence of α + β → α + β + Ti2Ni → Ti2Ni + β → Ti2Ni + CrNi2 + γ-Ni. The hardness of gradient coating increases as the relative percentage of Inconel625 correspondingly. When the relative percentage of nickel-based alloy reaches 100%, the hardness reaches a peak of 855 HV1. The hardness is attributed to the contribution from the formation of Ti2Ni precipitates, CrNi2 compounds as well as the solid solution hardening. For the high temperature properties, there is a diffusion zone at the interface between Ti6Al4V base layer and transition layer. The transverse microcracks are produced between layers at 800 °C.

Aims: There may exist an effect modification of hypertension on the relation of vitamin D deficiency with cardiovascular disease. The aim of this study was to investigate this interaction on coronary heart disease. Methods: We investigated 348 consecutive patients (mean age 62.4 ± 10.5 years; 56.3% male) who underwent coronary angiography because of chest discomfort at our heart center. Serum 25-OH vitamin D was also detected by ELISA method in these patients. Multivariable logistic regression models were used to estimate odd ratios (ORs) of CHD across vitamin D levels in hypertensives and normotensives, respectively. Results: We found the multivariable-adjusted ORs of CHD in the bottom(≤8.5 ng/ml) and middle tertiles (8.5–13 ng/ml) of 25-OH vitamin D were 2.86 (95% confidence interval [CI]: 1.38, 5.92) and 1.63 (0.83, 3.20), respectively, compared with those in top tertiles (>13ng/ml) among hypertensives (Ptrend=0.005). In contrast, the corresponding ORs of the above two groups were 0.88 (0.28, 2.74) and 1.23 (0.42, 4.00), respectively, in the normotensives (Ptrend = 0.800; Peffect modification = 0.020). The multivariable-adjusted OR of CHD in patients with severe hypovitaminosis D (

BACKGROUND: Peripartum cardiomyopathy (PPCM) is characterized by left ventricular systolic dysfunction and heart failure. However, its pathogenesis is not clear. Our preliminary study revealed that autoantibodies against β1-adrenergic receptors (β1R-AABs) and M2-muscarinic receptors (M2R-AABs) participated in heart failure regardless of primary heart disease. Whether β1R-AABs and M2R-AABs participate in the pathogenesis of PPCM is still unknown. METHODS: Totally 37 diagnosed PPCM patients and 36 normal pregnant women were enrolled in this study. Clinical assessment and 2-dimensional echocardiographic studies as well as the measurement of β1R-AABs or M2R-AABs by enzyme linked immunosorbent assay (ELISA) were performed. RESULTS: The positive rates for β1R-AABs and M2R-AABs were 59.5% (22/37) and 45.9% (17/37) in PPCM patients, and 19.4% (7/36) (P