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To investigate the oxygen adsorption characteristics of coal with different moisture contents, a molecular model of bituminous coal from Datong coalfield was constructed based on 13C-NMR and XPS analysis, combined with molecular mechanics (MM) and molecular dynamics (MD) methods. The oxygen adsorption characteristics of coal were studied using the Grand canonical Monte Carlo (GCMC) method at a temperature of 293.15 K, with a pressure range of 0–10 MPa, and moisture contents of 3.27%, 5.13%, 6.92%, and 8.65%, respectively. The results show that the molecular formula of the Datong bituminous coal structure model is C159H134O35N2S, with a density of 1.35 g/cm3. High moisture content coal has a lower molecular surface area and porosity, and oxygen adsorption on coal molecules follows type I isotherms. The amount of physical oxygen adsorption decreases with increasing moisture content. The heat of physical adsorption is negatively correlated with pressure, and high moisture content accelerates the decrease in heat of physical adsorption caused by increased pressure. [ABSTRACT FROM AUTHOR]

To improve the efficiency of coalbed methane and recoverability of reservoirs, enhanced fracturing technology is usually required to improve the low porosity and permeability status of coal reservoirs. As a feasible method for strengthening permeability, microwave–LN2 freeze–thaw (MLFT) cycles modify the microscopic pore structure of coal through the coupled effect of temperature stress changes, phase change expansion, and fatigue damage. 1H nuclear magnetic resonance combined with fractal dimension theory was used to characterize quantitatively the pore system and geometric features of coal. The geometric fractal model constructed using the T2 spectrum indicates that the fractal dimensions Dp and De have high fitting accuracy, demonstrating that percolation and effective pores exhibit good fractal characteristics. Dp and De are correlated negatively and positively, respectively, with the cyclic parameters. The relevance analysis shows that the NMR fractal method can reflect the pore–fracture heterogeneity of coal, which has a significant effect on the percentage of fluid migration space. This study reveals that MLFT cycles have significant enhancement effects on promoting the extension of multi-type pores structures within the coal matrix, as well as the connectivity and permeability of cracks. [ABSTRACT FROM AUTHOR]

The development of efficient methodologies for the controlled manufacture of specific stereoisomers bearing quaternary stereocenters has prompted advances in a variety of scientific disciplines including pharmaceutical chemistry, materials science, and chemical biology. However, complete control of the absolute and relative stereochemical configurations of alkyne derivatives remains an unmet synthetic challenge. Herein, a Ni/Cu dual‐catalyzed asymmetric propargylic substitution reaction is presented to produce propargylated products with all‐carbon quaternary stereocenters in high yields with significant diastereo‐ and enantioselectivities (up to >20:1 dr, >99% ee). The synthesis of all stereochemical variants of methohexital, a widely used sedative‐hypnotic drug, exemplifies the efficacy of dual‐catalyzed stereodivergent propargylation. [ABSTRACT FROM AUTHOR]

Addressing the challenge of achieving precise subtype classification of breast cancer histopathology images with limited resources, a lightweight model incorporating multi-stage information fusion and an attention mechanism is proposed for this task. Using MobileNetV3 as the backbone, a multi-stage fusion strategy captures the rich image information in breast cancer histopathology images. Additionally, the selective kernel (SK) attention mechanism is introduced in the initial stages of feature extraction, while an improved squeeze-and-excitation coordinate attention (SCA) mechanism is integrated in the later stages to enhance the extraction of both underlying and semantic features. The final feature representations for subtype classification are determined based on the attention map weights computed at each stage. The experimental results demonstrate the model's outstanding recognition performance on the BreakHis dataset, achieving subtype classification accuracies of 96.259%, 94.763%, 95.511%, and 94.015% at four different magnifications. [ABSTRACT FROM AUTHOR]

A highly effective oxidation cross-coupling method involving para -cresol derivatives and malononitrile derivatives has been developed utilizing undivided electrolytic conditions. This electrochemical approach offers a robust route for synthesizing diverse malononitrile derivatives featuring quaternary carbon centers and incorporating para -phenol groups. Notably, the direct electrooxidation of the C(sp3)–H bond in the para -cresol derivative plays a crucial role in this process under electrolytic conditions. Various para -cresol derivatives and malononitrile derivatives with different substituents are readily compatible with this electrochemical transformation, affording coupling compounds in up to 99% yield. [ABSTRACT FROM AUTHOR]

Intrinsic plasticity, a fundamental process enabling neurons to modify their intrinsic properties, plays a crucial role in shaping neuronal input‐output function and is implicated in various neurological and psychiatric disorders. Despite its importance, the underlying molecular mechanisms of intrinsic plasticity remain poorly understood. In this study, a new ubiquitin ligase adaptor, protein tyrosine phosphatase receptor type N (PTPRN), is identified as a regulator of intrinsic neuronal excitability in the context of temporal lobe epilepsy. PTPRN recruits the NEDD4 Like E3 Ubiquitin Protein Ligase (NEDD4L) to NaV1.2 sodium channels, facilitating NEDD4L‐mediated ubiquitination, and endocytosis of NaV1.2. Knockout of PTPRN in hippocampal granule cells leads to augmented NaV1.2‐mediated sodium currents and higher intrinsic excitability, resulting in increased seizure susceptibility in transgenic mice. Conversely, adeno‐associated virus‐mediated delivery of PTPRN in the dentate gyrus region decreases intrinsic excitability and reduces seizure susceptibility. Moreover, the present findings indicate that PTPRN exerts a selective modulation effect on voltage‐gated sodium channels. Collectively, PTPRN plays a significant role in regulating intrinsic excitability and seizure susceptibility, suggesting a potential strategy for precise modulation of NaV1.2 channels' function. [ABSTRACT FROM AUTHOR]

Hydraulic measures such as hydraulic slotting and hydraulic fracturing are commonly used in coal seam pressure relief and permeability enhancement. Two-phase flow patterns of CH4–water in pore-sized coal seams after hydraulic measures are critical to improve gas extraction efficiency. The phase field module in COMSOL Multiphysics™ 5.4 and the classical ordered porous media model were used in this paper. The characteristics of CH4–water two-phase immiscible displacement in coal seams under different capillary numbers (Ca) and viscosity ratios (M) were simulated and quantitatively analyzed. By changing the contact angle of the porous media, the flow patterns of CH4–water two-phase in coal with different wettability were simulated. Results show that wettability significantly affects the displacement efficiency of CH4. Additionally, by constructing a dual-permeability model to simulate the varying local permeability of the coal, the flow patterns of different Ca and M in dual-permeability media were further investigated. It is found that CH4 preferentially invades high-permeability regions, and the displacement efficiency in low-permeability regions increases with higher Ca and M, providing a reference for gas extraction from coal seams after hydraulic measures. [ABSTRACT FROM AUTHOR]

Summary: Multiple genome-wide association studies (GWAS) have identified specific genetic variants in the coiled-coil domain containing 92 (CCDC92) locus that is associated with obesity and type 2 diabetes in humans. However, the biological function of CCDC92 in obesity and insulin resistance remains to be explored. Utilizing wild-type (WT) and Ccdc92 whole-body knockout (KO) mice, we found that Ccdc92 KO reduced obesity and increased insulin sensitivity under high-fat diet (HFD) conditions. Ccdc92 KO inhibited macrophage infiltration and fibrosis in white adipose tissue (WAT), suggesting Ccdc92 ablation protects against adipose tissue dysfunction. Ccdc92 deletion also increased energy expenditure and further attenuated hepatic steatosis in mice on an HFD. Ccdc92 KO significantly inhibited the inflammatory response and suppressed the NLR Family Pyrin Domain Containing 3 (NLRP3) inflammasome in WAT. Altogether, we demonstrated the critical role of CCDC92 in metabolism, constituting a potential target for treating obesity and insulin resistance.

Glow discharge ionization source can be used to analyze solid sample, liquid sample and gas sample. At present, glow discharge optical emission spectrometer (GD-OES) and glow discharge mass spectrometer (GD-MS) are mainly used to the elemental analysis of inorganic solid samples and quantitative depth profile analysis, including direct current (DC) power supply and radio frequency (RF) power supply. In this paper, the ionization of liquid sample and gas sample by low frequency radio frequency glow discharge (Lf-RFGD) was researched, and the glow discharge structure constructed was connected to timeof flight mass spectrometer(TOF MS). The influences of the vacuum degree of ionization chamber, the size of sample inlet capillary, the auxiliary gas pressure, the discharge radio frequency and the voltage difference between electrode plates on the ionization efficiency were studied. The optimal analysis conditions are the vacuum degree of ionization chamber is about 30 Pa, the length of sample inlet capillary is 150 mm and the inner diameter is 0.25 mm, the auxiliary gas pressure is about1.0 MPa, the low discharge frequency is 2 MHz, the voltage difference between electrode plates is about 100 V. Under these conditions, the discharge power is about 20 W,the detection limit of liquid sample is 0.1 pg and volatile sample is 20 mg/m3, and the detection resolution (full width at half maximum, FWHM) is about 3 000. Combined with samples testing, the Lf-RFGD TOF MS was preliminarily applied to the drug solution and volatile organic compounds (VOCs). However, the sensitivity of this instrument for detecting non volatile liquid sample was not good compared with the conventional detection instrument. The reason is that high proton affinity and low ionization potential are needed to obtain good detection sensitivity in the positive ion mode of mass spectrometer, and non volatile liquid sample without pretreatment is not easy to meet the condition of high proton affinity under low power glow discharge condition. Successfully, a lowcost, portable approach based on the application of atmospheric sampling Lf-RFGD TOF MS has been developed for near real time measurement of trace VOCs. In this context, the glow discharge excitation source offers attractive alternative for development of low cost VOCs and elemental analysis instrument. Lf-RFGD as an excitation source has unique advantages with respect to development of hand held instrument such as low cost, low power consumption, and analytical versatility.