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Objective To profile the genome-wide distribution of H3K27ac-marked enhancers in gastric intestinal metaplasia (IM) tissues and to investigate the potential regulatory mechanism of enhancers on IM. Methods IM tissues from 41 patients and normal gastric mucosa from 21 healthy individuals were collected for analysis using Cleavage Under Targets and Tagmentation (CUT&Tag) sequencing and RNA sequencing. The number and signal intensity of H3K27ac modifications in the 2 tissues were compared to reveal the reprogramming characteristics of the enhancers in the IM tissues. Meanwhile, the underlying regulatory mechanism of enhancer-associated transcription factors on the expression of IM-related genes were investigated. Results As compared with normal gastric mucosa, the number and signal intensity of H3K27ac modifications were significantly elevated in the IM tissues, and the reprogramming areas were mainly located in the enhancers. The enhancers with greatly increased activity accounted for 92.4% of all variant enhancer loci in IM, which improved the expression of many intestinal epithelium-related genes, leading to altered phenotypes and biological properties of metaplastic mucous cells. The binding motifs of 14 transcription factors including CDX2 were identified by enrichment analysis in the enhancer loci. These transcription factors were up-regulated in the IM tissues and thus constituted a transcriptional regulatory network, and may play an important role in enhancer activating IM-related genes. Conclusion Through integration analysis of epigenetic and transcriptomic sequencing, enhancer reprogramming is identified as a critical epigenetic modification feature in gastric IM. Multiple transcription factors like CDX2 might be recruited to the enhancer loci, and then generate a regulatory network to synergistically up-regulate the expression of IM-related genes.

Objective To systemically characterize the genome-wide distribution of H3K27me3-marked silencers in gastric intestinal metaplasia (IM) tissues and to elucidate a novel epigenetic regulatory mechanism of IM. Methods Gastric antrum mucosa samples were collected from 22 healthy individuals and 39 patients with IM. The modification of H3K27me3 and the transcriptome characteristics were detected by Cleavage Under Targets and Tagmentation (CUT&Tag) sequencing and RNA sequencing, respectively. Various bioinformatics tools, such as Ngsplot, ChIPseeker, MAnorm2, GGBiPlot, edgeR, Homer and others were applied for analyzing the silencer signal and its regulation on gene expression of IM tissues. Results CUT&Tag sequencing and RNA sequencing data were of great quality, and there was no significance in the whole-genome distribution of H3K27me3 modification between normal gastric mucosa and IM tissues. Genome-scale distribution of H3K27me3-marked silencers was also portrayed, which revealed weakened silencer signal intensity in IM tissues (P < 0.05). Principal component analysis (PCA) showed that the silencer characteristics in IM were greatly different from those in normal tissues, indicating extensive silencer remodeling in the IM tissues. Combined with RNA sequencing analysis, silencer remodeling was closely associated with the increased expression of CDX1 and other IM-related genes, as well as with the possible activation of IM-related metabolic pathways. In addition, loss of silencer signal recruited various transcription factors such as ATOH1 (P < 0.01) and ONECUT2 (P < 0.01) to form a regulatory network, which were highly expressed in IM tissues, regulating the expression of CDX1 and other key genes of IM, and affecting cell biological processes like coll fate commitment. Conclusion Integration analysis of epigenetic and transcriptomic sequencing data discovers silencer remodeling as a hallmark epigenetic feature in gastric IM tissues. Loss-of-function in silencer loci may recruit IM-regulatory transcription factors such as ATOH1 and ONECUT2, which may generate a network to impact on the expression of key genes and the metabolism of IM cells.

To compare the clinical efficacy of artificial total hip arthroplasty(THA) for femoral neck fracture between direct anterior approach(DAA) in lateral position and posterior lateral approach(PLA). Methods: Comparison of 200 cases of patients who underwent THA collected between September 2019 and August 2021 was done. Incision length, intraoperative bleeding, operative time, difference in postoperative haemoglobin from preoperative levels, length of hospital stay, postoperative time to get off the floor, visual analogue score (VAS) for pain, preoperative and postoperative Harris scores for the hip, and measurements of the acetabular abduction angle and anterior acetabular tilt angle at 6 months postoperatively were collected, and all the cases were followed up for at least 2 years. Results: Compared with the PLA group, the DAA group had a shorter incision length, less intraoperative blood loss, less postoperative haemoglobin reduction compared with the preoperative period, a shorter hospital stay and an earlier first time to get off the floor after surgery, however, the comparison of operative times was not statistically significant; Patients in the DAA group had a lower VAS in the early postoperative period compared to PLA; Patients in the DAA group had higher hip Harris scores at 6 weeks and 6 months postoperatively; There was no significant difference in acetabular abduction angle and acetabular anterior tilt angle between the two groups at 6 months postoperatively. Conclusion: Compared to PLA, DAA in THA is minimally invasive, has less pain, less bleeding, earlier time out of bed, shorter hospital stay, better early hip function, faster rehabilitation, and better joint stability. [ABSTRACT FROM AUTHOR]

Dedicated to synchronously acquiring large-area, high-precision, and multi-scale ocean wind and wave information, a novel concept of a spaceborne ocean microwave dual-function integrated sensor is proposed in this paper. It integrates the functions of a scatterometer and SAR by sharing a single phased-array antenna. An overview of the scientific requirements and motivations for the sensor are outlined firstly. In order to fulfill the observation requirements of both the functions, the constraints on the system parameters such as frequency, antenna size, and incidence angle are analyzed. Then, the selection principles of these parameters are discussed within the limitations of antenna area, bandwidth, available time, and cost. Additionally, the constraints on the time sequence of transmitting and receiving pulses are derived to ensure that there is no conflict when the two functions operate simultaneously. Subsequently, a method for jointly designing the pulse repetition frequency (PRF) of both the functions is introduced, along with zebra maps to verify its effectiveness. At the end of the paper, the system and performance parameters of the sensor are given for further insight into it. [ABSTRACT FROM AUTHOR]

Parametric splines are popular tools for precision optical metrology of complex freeform surfaces. However, as a promising topologically unconstrained solution, existing T-spline fitting techniques, such as improved global fitting, local fitting, and split-connect algorithms, still suffer the problems of low computational efficiency, especially in the case of large data scales and high accuracy requirements. This paper proposes a speed-improved algorithm for fast, large-scale freeform point cloud fitting by stitching locally fitted T-splines through three steps of localized operations. Experiments show that the proposed algorithm produces a three-to-eightfold efficiency improvement from the global and local fitting algorithms, and a two-to-fourfold improvement from the latest split-connect algorithm, in high-accuracy and large-scale fitting scenarios. A classical Lena image study showed that the algorithm is at least twice as fast as the split-connect algorithm using fewer than 80% control points of the latter. [ABSTRACT FROM AUTHOR]

The deep integration of Internet of Medical Things (IoMT) and Artificial intelligence makes the further development of intelligent medical services possible, but privacy leakage and data security problems hinder its wide application. Although the combination of IoMT and federated learning (FL) can achieve no direct access to the original data of participants, FL still can't resist inference attacks against model parameters and the single point of failure of the central server. In addition, malicious clients can disguise as benign participants to launch poisoning attacks, which seriously compromises the accuracy of the global model. In this paper, we design a new privacy protection framework (BFG) for decentralized FL using blockchain, differential privacy and Generative Adversarial Network. The framework can effectively avoid a single point of failure and resist inference attacks. In particular, it can limit the success rate of poisoning attacks to less than 26%. Moreover, the framework alleviates the storage pressure of the blockchain, achieves a balance between privacy budget and global model accuracy, and can effectively resist the negative impact of node withdrawal. Simulation experiments on image datasets show that the BFG framework has a better combined performance in terms of accuracy, robustness and privacy preservation. [ABSTRACT FROM AUTHOR]

Mo, TiH2, Al and graphite elemental powders were used as starting materials for the activation reaction sintering process, which was employed to fabricate porous Mo2TiAlC2. The alteration of phase constitution, volume expansion, porosity, pore size and surface morphology of porous Mo2TiAlC2 with sintering temperatures ranging from 700 °C to 1500 °C were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and pore size tester. Both the pore formation mechanism and activation reaction process at each temperature stage were investigated. The experimental results illustrate that the sintered discs of porous Mo2TiAlC2 exhibit obvious volume expansion and pore structure change during the sintering process. Before 1300 °C, the volume expansion rate and porosity increase with the increment of temperature. However, with the sintering temperature above 1300 °C, the volume expansion rate and porosity decrease. At the final sintering temperature of 1500 °C, porous Mo2TiAlC2 with a volume expansion rate of 35.74%, overall porosity of 47.1%, and uniform pore structure was synthesized. The pore-forming mechanism of porous Mo2TiAlC2 is discussed, and the evolution of pressed pores, the removal of molding agents, the decomposition of TiH2, and the Kirkendall effect caused by different diffusion rates of elements in the diffusion reaction are all accountable for the formation of pores. [ABSTRACT FROM AUTHOR]

Ce-MnOx composite oxide catalysts with different proportions were prepared using the coprecipitation method, and the CO-removal ability of the catalysts with the tested temperature range of 60–140 °C was investigated systematically. The effect of Ce and Mn ratios on the catalytic oxidation performance of CO was investigated using X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), H2 temperature programmed reduction (H2-TPR), CO-temperature programmed desorption (CO-TPD), and in situ infrared spectra. The experimental results reveal that under the same test conditions, the CO conversion rate of pure Mn3O4 reaches 95.4% at 170 °C. Additionally, at 140 °C, the Ce-MnOx series composite oxide catalyst converts CO at a rate of over 96%, outperforming single-phase Mn3O4 in terms of catalytic performance. With the decrement in Ce content, the performance of Ce-MnOx series composite oxide catalysts first increase and then decrease. The Ce MnOx catalyst behaves best when Ce:Mn = 1:1, with a CO conversion rate of 99.96% at 140 °C and 91.98% at 100 °C. [ABSTRACT FROM AUTHOR]

Ionic conductive hydrogels with good conductivity and biocompatibility have become one of the research highlights in the field of wearable flexible sensors and supercapacitors. In this work, poly(methacrylic acid–methyl methacrylate)-reinforced poly(sodium acrylate–vinyl phosphonic acid) composite hydrogels (P(AAS-VPA)/PMMS) were designed and tested for strain sensor or supercapacitor applications. The results showed recoverability for 20 cycles of tension and compression experiments, an excellent breaking strain of 2079%, and ionic conductivity of 0.045 S·cm−1, demonstrating strong support for the application of the P(AAS-VPA)/PMMS hydrogel in strain sensors and supercapacitors. The composite hydrogel exhibited outstanding sensing and monitoring capability with high sensitivity (GF = 4.0). The supercapacitor based on the P(AAS-VPA)/PMMS composite hydrogel showed excellent capacitance performance (area capacitance 100.8 mF·cm−2 and energy density 8.96 μWh·cm−2) at ambient temperature and even −30 °C (25.3 mF·cm−2 and 2.25 μWh·cm−2). The hydrogel has stable electrochemical stability (1000 cycles, Coulomb efficiency > 97%) and exhibits electrochemical properties similar to those in the normal state under different deformations. The excellent results demonstrate the great potential of the P(AAS-VPA)/PMMS composite hydrogel in the field of strain sensors and flexible supercapacitors. [ABSTRACT FROM AUTHOR]