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Hydrogen masters have high short-term stability, using them as master clocks can generate high-precision local standard time in a short period of time. However, the hydrogen maser has a frequency drift phenomenon, which leads to its poor long-term stability, thus affecting the accuracy of the local time. The rotation of the millisecond pulsar is highly stable. With the help of its high long-term stability, it can regularly control the frequency of the hydrogen atomic clock, thus control the real-time signal. The stability of four millisecond pulsars in the second data set released by the International Pulsar Timing Array (IPTA) is analyzed. At the same time, the frequency stability of a hydrogen maser of the National Time Service Center of the Chinese Academy of Sciences (NTSC) is analyzed by Hadamard variance. Finally, a strategy for steering the frequency of hydrogen master using pulsars is given. [ABSTRACT FROM AUTHOR]

The CCAAT/enhancer-binding proteins (C/EBPs) constitute a family of pivotal transcription factors involved in tissue development, cellular function, proliferation, and differentiation. NFIL3, as one of them, plays an important role in regulating immune cell differentiation, circadian clock system, and neural regeneration, yet its specific DNA recognition mechanism remains enigmatic. In this study, we showed by the ITC binding experiments that NFIL3 prefers to bind to the TTACGTAA DNA motif. Our structural studies revealed that the α-helical NFIL3 bZIP domain dimerizes through its leucine zipper region, and binds to DNA via its basic region. The two basic regions of the NFIL3 bZIP dimer were pushed apart upon binding to DNA, facilitating the snug accommodation of the two basic regions within the major grooves of the DNA. Remarkably, our binding and structural data also revealed that both NFIL3 and C/EBPa/ß demonstrate a shared preference for the TTACGTAA sequence. Furthermore, our study revealed that disease-associated mutations within the NFIL3 bZIP domain result in either reduction or complete disruption of its DNA binding ability. These discoveries not only provide valuable insights into the DNA binding mechanisms of NFIL3 but also elucidate the causal role of NFIL3 mutations in disease pathogenesis. [ABSTRACT FROM AUTHOR]

This study investigated the antimony (Sb) adsorption behavior on newly prepared montmorillonite (Mt)-immobilized nanoscale zero-valent iron (nZVI) (hereafter Mt-nZVI) in aqueous solution. Mt-nZVI showed the highest Sb adsorption capacity (71-76 mg·Sb·g-1 adsorbent) at pH 4-8. The pseudo-first-order and pseudo-second-order kinetic models fitted well (R2 3 0.992) with the experimental data on Sb adsorption onto Mt-nZVI. The Langmuir isotherm model (R² = 0.99) was more suitable than the Freundlich isotherm model (R² = 0.95) for describing the adsorption of Sb on Mt-nZVI. Mt-nZVI had an almost 7 times higher theoretical Sb adsorption capacity than nZVI when calculated in terms of Fe. Neither 0.01 M phosphate nor 0.01 M sulfate had a significant effect the Sb adsorption capacity of Mt-nZVI, and more than 80% of the Sb adsorption capacity remained in the presence of 0.001-0.1 M NaCl or 1-30 mg·L-1 humic acid. However, the presence of 0.01 M silicate or carbonate or 0.0001 M arsenate significantly affected the Sb adsorption capacity of Mt-nZVI. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides exhibit tremendous potential for sodium ion batteries (SIBs), owing to the outstanding specific capacity and aboundant reserves. However, the large ionic radius of sodium and poor conductivity often result in the fast decaying performance and inferior reaction kinetics. Herein, the GeS 2 /GeO 2 /ZnS@rGO (GGZ/C) ternary metal-based composite is fabricated as an anode material for SIBs. Notably, the GGZ/C composite is derived from the phase transformation of Zn 2 GeO 4 precursor, which is beneficial for the heterostructure engineering. In this hierarchical structure, the metal phases ZnS and GeO 2 are used to form the heterogeneous framework, while graphene is applied to build a conductive network and anchor the host nanoparticles. Therefore, the great Na+ diffusion channels are achieved by the rational design of the huge exquisite interfaces among the heterogeneous mixed phases. Notably, it can almost completely relieve the volume expansion and restrain the internal stress of GGZ/C composite, providing the excellent structural tolerance. As expected, the GGZ/C composite exhibits excellent rate capability, with an impressive reversible capacity of 548 mAh g−1 at a high rate of 5.0 A g−1. Meanwhile, the GGZ/C also displays outstanding cycling performance with a specific capacity of 519 mAh g−1 after 650 cycles at high rate of 5.0 A g−1. This strategy offers the inspiration for rational heterostructure engineering for the energy storage materials with excellent reversible capacity and large volume variation. [ABSTRACT FROM AUTHOR]

Tubulointerstitial fibrosis (TIF) is essential during the development of end-stage kidney disease (ESKD) and is associated with the impairment of fatty acid oxidation (FAO). Kruppel-like factor 14 (KLF14) is an important gene in lipid metabolism, but its role in TIF remains unknown. TGF-β-stimulated HK-2 cells and mouse unilateral ureteral obstruction (UUO) were used as renal fibrosis models. The role of KLF14 in the process of renal fibrosis was verified by gene knockout mice, genetic or pharmacological interference in animal model and cell model respectively. In the current study, we found that KLF14 expression increased after activation of the TGF-β signaling pathway during TIF. In KLF14−/− mice, more severe fibrosis was observed after unilateral ureteral obstruction (UUO) was induced. In human HK2 cells, knockdown of KLF14 led to more severe fibrosis induced by TGF-β1, while overexpression of KLF14 partially attenuated this process. Specifically, KLF14 deficiency decreased mitochondrial FAO activity, resulting in lipid accumulation. Thus, the energy supply to the cells was insufficient, finally resulting in TIF. We further proved that KLF14 could target peroxisome proliferator activated receptor alpha (PPARα) as a transcriptional activator. This study identified the upregulation of KLF14 expression in response to kidney stress during the process of fibrosis. Upon TIF, the activated TGF-β signaling pathway can enhance KLF14 expression, while the upregulation of KLF14 expression can decrease the degree of TIF by improving FAO activity in tubular epithelial cells and recovering the energy supply mediated by PPARα. [Display omitted] • Upregulation of KLF14 expression in response to kidney stress during the process of fibrosis. • Upon tubulointerstitial fibrosis, the activated TGF-β signaling pathway can enhance KLF14 expression. • KLF14 can decrease the degree of tubulointerstitial fibrosis by improving fatty acid oxidation activity in tubular epithelial cells. • Klf14 plays a role in improving fatty acid oxidation through transcriptional regulation of PPARα. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) has been implemented in various fields, including speech recognition. In this paper, a computational method is proposed for calculating the similarity between different languages or language varieties, with their similarity represented in terms of distance. In this process, we extracted mel spectrogram features from speech signals to provide the feature vectors and derived pairs of signal tokens based on vectors. Then, we trained a Siamese time-delay neural network to calculate the distance between two signal tokens. If the token pairs are from the same language group, the distance obtained using this Siamese network model is zero. In this preliminary experiment, three types of regional Mandarin Chinese (BJ, FJ, GD) were used as the dataset. The results gave the F1-score of 0.794, 0.623, and 0.715 for the classification task with respect to BJ, FJ, and GD dataset. In addition, 10 Taiwan Mandarin (TM) native speakers participated in identification and a pair-wise discrimination experiment to allow comparison with the Siamese network model. The 10 TM natives tended to misidentify GD-accented Mandarin as FJ-accented Mandarin resulting in a much greater distance between the two in the FJ-GD discrimination task compared to the Siamese network model. Overall, the results show that the performance of our model is better than the comparative experiment in completing the identification task, with the distance between the Siamese network model and the experiment having a mean absolute error (MAE) of 0.35. The familiarity might be the reason why the 10 TM natives displayed a bias towards BJ-accented Mandarin Chinese. To sum up, we provide a computational method to calculate the distance between two languages or language varieties, which can help linguists pre-classify sound files. [ABSTRACT FROM AUTHOR]

In order to realize the low-carbon gasification of the typical wet stalks, the graphite was used as the microwave-absorbing agent and the heat transfer medium in the microwave field, and CO 2 was used as the gasification agent to explore the characteristics of microwave CO 2 gasification. After mixing the corn stalks, the rice stalks or the wheat stalks with different water contents and the graphite in a mass ratio of 4:1, CO 2 was introduced for gasification in a microwave field. Experiments showed that with the increase in the water content, the carbon conversions, the gas yields and the volume fractions of the effective components all increased slowly in the front and rear sections, and increased rapidly in the middle section. When the CO 2 flow rate was 0.6 Nm3·kg−1·min−1, the carbon conversions, the gas yields and the volume fractions of the effective components all reached their peaks. It was found that the structure of the three stalks changed from smooth to porous during the intermediate process of the graphite-assisted microwave gasification. The deashed stalks with water content of 60 % was gasified in a microwave field of 700 W for 1.25 min, and the BET specific surface areas of the generated porous carbon reached 2041–2054 m2 g−1, and the volume fractions of the effective components of the gasification gas were more than 95 %. With the prolongation of the gasification time, the carbon conversions increased slowly in the early and late stages, but increased rapidly in the middle stage. The reason was that the large amount of porous carbon generated in the middle stage was the gasifiable strong microwave-absorbing agent, which greatly increased the gasification temperature and accelerated the reaction rates. When the graphite was reused 10 times, the carbon conversions could still reach more than 80 %. The XRD tests were carried out on the graphite used many times to explore its deactivation mechanism. This paper has practical significance for the low-carbon CO 2 recycling of stalks biomass, and provides a new way for the preparation of biomass-based porous carbon. It provided a new idea for the preparation of the biomass-based porous carbon. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Global crude steel production reached 1.6 billion tonnes in 2015, registering an increase of 41% from 2005 levels, half of which is produced by China alone. Amongst other low-carbon technologies, Carbon Capture and Storage (CCS) is identified as a key technology that will help achieve the much-needed emission reductions in the iron/steel sector. This paper delineates a techno-economic analysis of a hypothetical first-of-its-kind CO 2 capture and storage project with a 0.5-million tonne of CO 2 per annum capture capacity, using amine capture technology, in a generic Chinese steel plant. The technical configuration of the project was modelled using the Advanced System for Process Engineering (ASPEN) accompanied by a financial model analysis. The cost of CO 2 avoidance for the modelled project with transport and storage was estimated at CNY448/tCO 2 (USD65.2/tCO 2). The cost of CO 2 avoidance is sensitive to a number of assumptions, including the discount rate and the cost of CO 2 transportation and storage. There is also potential for cost reductions in transport and storage if the project were to share infrastructure with large stationary emission sources. [ABSTRACT FROM AUTHOR]