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As a ferromagnetic topological semimetal with a strong anomalous Hall effect (AHE), Co3Sn2S2 has been extensively explored for manipulating the topological state via the changed magnetic order as well as device applications connecting dissipationless spin and charge transport1-3. However, the main challenge is the improvement of the crystal quality, which is crucial for enhancing physical properties including AHE, carrier mobility, and magnetoresistance4,5. Here, we report the synthesis of ultra pure Co3Sn2S2 single crystals with an ultra low impurity density by an innovative crystal-sourced chemical vapor transport (CS-CVT) approach, achieving ultrahigh anomalous Hall angle (AHA) of 40%, carrier mobility and magnetoresistance (MR) of 10490 cm2V-1s-1 and 2500%, respectively. These values represent a huge improvement on previously reported highest values of either pristine or doped Co3Sn2S2 (of 33%, 2600 cm2V-1s-1, and 180% respectively)4,6. Equally importantly, the anomalous Hall conductivity (AHC) of our crystals reached 1600 Ω-1cm-1, which is larger than the theoretically predicted value of 1310 Ω-1cm-1 from the integral of Berry curvature7. Observation of an ultranarrow flat band and topological surface states near the Fermi level provides good microscopic understanding of this gigantic anomalous Hall effect. Our high-quality magnetic topological materials are expected to facilitate a full understanding of the strong electronic correlation and may perhaps lead to the discovery of a quantum AHE in the 2D limit.

Azobenzene liquid-crystal shape memory polyurethanes with photo-thermo-synergy responses.

Recent studies demonstrate that histones are subjected to a series of short-chain fatty acid modifications that is known as histone acylations. However, the enzymes responsible for histone acylations in vivo are not well characterized. Here, we report that HBO1 is a versatile histone acyltransferase that catalyzes not only histone acetylation but also propionylation, butyrylation and crotonylation both in vivo and in vitro and does so in a JADE or BRPF family scaffold protein-dependent manner. We show that the minimal HBO1/BRPF2 complex can accommodate acetyl-CoA, propionyl-CoA, butyryl-CoA and crotonyl-CoA. Comparison of CBP and HBO1 reveals that they catalyze histone acylations at overlapping as well as distinct sites, with HBO1 being the key enzyme for H3K14 acylations. Genome-wide chromatin immunoprecipitation assay demonstrates that HBO1 is highly enriched at and contributes to bulk histone acylations on the transcriptional start sites of active transcribed genes. HBO1 promoter intensity highly correlates with the level of promoter histone acylation, but has no significant correlation with level of transcription. We also show that HBO1 is associated with a subset of DNA replication origins. Collectively our study establishes HBO1 as a versatile histone acyltransferase that links histone acylations to promoter acylations and selection of DNA replication origins.

Neonatal congenital heart disease (CHD) is the most common congenital anomaly. As a practical matter of people's livelihood, cardiac ultrasonography was performed on potential CHD children in 11 cities eastern China. In this study, we aimed to document the birth prevalence of CHD and its socioeconomic and geographical distribution, as supported by this public health policy. In this study, the diagnosis of CHD was made based on echocardiography. Geographical and socioeconomic factors were determined by the Statistical Bulletin on National Economic and Social Development (SBNESD). 51857 newborns from the Network Platform for Congenital Heart Disease (NPCHD) from January to December 2019 in 11 cities eastern China were included. The total birth prevalence of CHD was 5.79 per 1000 births. The study on the low-income areas, mountainous areas, areas with low medical institution bed level, and with high qualification of medical personnel reported a signifcantly higher birth prevalence of CHD compared with high-income cities, flat areas, areas with high medical institution bed level, and with low qualification of medical personnel. ASD, VSD, PDA, PS, TOF, atrioventricular septal defect, coarctation of the aorta, TAPVD, TGA and pulmonary atresia are the most frequent subtypes. ASD, VSD, PDA, PS, atrioventricular septal defect, coarctation of the aorta and pulmonary atresia showed a female preponderance, while TOF, TGA and TAPVD showed a male preponderance. Our study gives a relatively realistic prevalence of CHD after cardiac ultrasound examination of newborns suspected positive with CHD. Significant differences across geographical regions, income levels, and health service access were observed. In the future, population-wide cardiac ultrasound screening, prospective birth defect registries, and systematic medical follow-up programs covering the entire eastern or even China are needed to determine the exact birth prevalence.

We aim to explore the link between maternal weekly temperature exposure and CHD in offspring and identify the relative contributions from heat and cold and from moderate and extreme atmospheric temperature. From January 2019 to December 2020, newborns who were diagnosed with CHD by echocardiography in the Network Platform for Congenital Heart Disease (NPCHD) from 11 cities in eastern China were enrolled in the present study. We appraised the exposure lag response relationship between temperature and CHDs in the distributed lag nonlinear model and further probed the pooled estimates by multivariate meta-analysis. We further performed the exposure-response curves in extreme temperature (5

In this paper, we propose a family of non-stationary combined ternary ( 2 m + 3 ) \left(2m+3) -point subdivision schemes, which possesses the property of generating/reproducing high-order exponential polynomials. This scheme is obtained by adding variable parameters on the generalized ternary subdivision scheme of order 4. For such a scheme, we investigate its support and exponential polynomial generation/reproduction and get that it can generate/reproduce certain exponential polynomials with suitable choices of the parameters and reach 2 m + 3 2m+3 approximation order. Moreover, we discuss its smoothness and show that it can produce C 2 m + 2 {C}^{2m+2} limit curves. Several numerical examples are given to show the performance of the schemes.

Shape memory polymers (SMPs) can be repeatedly deformed and recovered to their original shapes, and thus have been rapidly developed in recent decades. However, there remains an urgent need for SMPs with both shape memory and self-healing properties. Here, we report star-shaped memory polyurethanes that exhibit thermally responsive shape memory properties and self-healing properties, and maintain the shape memory properties after undergoing thermally induced self-healing. This work expands the current understanding of the hydrogen-bond interaction features in both thermally responsive and thermally-induced self-healing SMPs.

A new type of sisal-based shape memory polyurethane foam (SMPU-PSF) was prepared by the chemical cross-linking of hydroxyl groups on sisal cellulose (PSF) with polycaprolactone and MDI, which used PSF as the active site, silicone oil as the stabilizer, and water as the foaming agent. The effects of different sisal microcrystalline contents on the thermal properties of SMPU-PSF were systematically studied using FT-IR, TG, and DSC, and the size and morphology of vesicles was observed using SEM. The mechanical properties of SMPU-PSF were studied via a compression test at room temperature. However, the shape memory process of SMPU-PSF was observed by means of thermal stimulation. The results showed that the SMPU-PSF has a good shape memory, high recovery rate, and good thermal stability, and its maximum decomposition temperature is about 360 °C. This work demonstrates that the new sisal-based shape memory polyurethane foam will have many applications in new smart science.

Change detection (CD) is one of the most important application in remote sensing domain. The difference image (DI) generated by traditional change detection methods are sensitive to several factors, such as atmospheric condition changes, illumination variations, sensor calibration, and speckle noise, greatly affecting the detection performance. To avoid the aforementioned problem, in this paper, a novel approach based on superpixel segmentation and image regression is proposed to detect changes between bitemporal synthetic aperture radar (SAR) images. Specifically, the bitemporal images are firstly divided into a number of superpixel pairs under the guidance of segmentation result of a pre-DI. Next, each pixel in pre-event image is reconstructed utilizing its nearest neighbor to reduce the influence of noise. Then, a set of preselected unchanged sample are selected to learn the local regression model and to estimate the post-event image. After that, the final DI can be obtained by measuring the difference between estimated post-event image and the actual one. Finally, the fuzzy c-means (FCM) clustering algorithm is adopted to generate the binary change map. Adequate experiments on four SAR datasets have been tested, and the experimental results compared with the state-of-the-art methods have proved the superiority of the proposed method.

A series of novel porphyrin monomers with different tail lengths were synthesized through the Alder–Longo method, and the corresponding polymers were successfully synthesized via radical polymerization. The structures of the porphyrin monomers and polymers were all depicted through proton nuclear magnetic resonance (1H-NMR) and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry, and the photophysical and electrochemical properties were confirmed through UV–Vis spectroscopy, photoluminescence spectroscopy, and cyclic voltammetry. The results showed that the polymers exhibited a deep highest occupied molecular orbital (HOMO) energy level and a large optical band gap, demonstrating their usefulness in photovoltaic devices. All of the porphyrin monomers formed a typical columnar phase, and the cleaning point of these porphyrin monomers reduced with the increasing length of the alkoxy tail chain. Thermogravimetric analysis demonstrated that the polymers had excellent thermal stability; the decomposition temperature was higher than 400 °C. The UV absorption spectrum of the polymers was between 400 and 670 nm. Compared with the absorption peak of the solution, the absorption peak after film formation presented a certain redshift. The HOMO level was lower than the stable critical level of the conjugated polymer in air (− 5.2 eV), indicating that the polymer is stable in air. In addition, the lowest unoccupied molecular orbital energy level was 0.49–0.64 eV, which was higher than that of the recipient PCBM, indicating that the polymers can be used as a donor material for solar cells.

Though graphene paper consisting of layer-by-layer stacked graphene nanosheets (GNs) has been widely used as a heat spreader due to the high in-plane thermal conductivity, the drawback of graphene paper is that it shows low through-plane thermal conductivity at the same time. In this study, polyamine-functionalized perylene bisimide derivative (APBI)/graphene nanosheet hybrid paper (AGP) samples with a “brick-and-mortar” structure were fabricated via the noncovalent functionalization of GNs and APBI. APBI can not only greatly improve the through-plane thermal transport but it also improves the mechanical properties of AGP. The through-plane thermal conductivity of AGP reaches 6.67 W m−1 K−1 with 42.36 wt% APBI and the tensile strength of AGP reaches 47.9 MPa with 14.22 wt% APBI. AGP, with both good thermal transport properties and mechanical properties, is expected to be used for thermal management applications as a heat spreader in industry.

The ubiquitous interdependencies among higher-dimensional states of neighboring agents can be characterized by matrix-weighted networks. This paper examines event-triggered global consensus of matrix-weighted networks subject to actuator saturation. Specifically, a distributed dynamic event-triggered coordination strategy, whose design involves sampled state of agents, saturation constraint and auxiliary systems, is proposed for this category of generalized network to guarantee its global consensus. Under the proposed event-triggered coordination strategy, sufficient conditions are derived to guarantee the leaderless and leader-follower global consensus of the multi-agent systems on matrix-weighted networks, respectively. The Zeno phenomenon can be excluded for both cases under the proposed coordination strategy. It turns out that the spectral properties of matrix-valued weights are crucial in event-triggered mechanism design for matrix-weighted networks with actuator saturation constraint. Finally, simulations are provided to demonstrate the effectiveness of proposed event-triggered coordination strategy. This work provides a more general design framework compared with existing results that are only applicable to scalar-weighted networks., arXiv admin note: substantial text overlap with arXiv:2106.06198

Gastric cancer (GC) is one of the most malignant tumors with high morbidity and mortality in the world, particularly in China. Erastin, a classical ferroptosis inducer, exerts cytotoxicity in several types of cancer cells including gastric cancer cells. However, the mechanism of erastin in regulating metabolic pathways in gastric cancer remains largely unclear. To investigate the gastric cellular response to erastin therapy, we adopted a cell pseudotargeted metabolomics method based on liquid chromatography-hybrid triple quadrupole linear ion trap mass spectrometry (LC-QTRAP MS). The developed method was used to investigate the differential metabolites between erastin-treated MGC-803 cells and the controls at different time points. We found that erastin induced tremendous impact on the metabolome of gastric cells by affecting key metabolic processes, such as cysteine and methionine metabolism, glutathione (GSH) biosynthesis, glycolysis and TCA cycle. Interestingly, S-adenosylmethionine (SAM), methionine, serine, glycine and cysteine were obviously increasing treads after erastin treatment, but S-adenosylhomocysteine (SAH) and GSH were always down-regulated up to 48 h. The results indicated that DNA methylation was activated and glutathione biosynthesis was blocked in erastin-treated MGC-803 gastric cells, highlighting the importance of erastin as a promising drug candidate for in vivo treatment of gastric tumor.