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The creation of van der Waals (vdW) ferromagnets with tunable Curie temperature (TC) and magnetic anisotropy is essential in developing vdW magnet-based devices. Here, we report an effective and reliable method for modulating the magnetic properties of vdW Fe5GeTe2 by site-specific Ga+ implantation. In this study, we report an easy axis in the ab-plane for bulk Fe5GeTe2 (TC = 310 K) and an axis out of the plane for thin Fe5GeTe2 flakes (TC = 290 K). Combining element-resolved photoemission electron microscopy and spatially resolved magneto-optic Kerr microscopy, we find that the implantation of a tiny amount of 10−3 Ga+·Å−3 in Fe5GeTe2 greatly enhances the TC from 290 to 360 K and switches the magnetic easy axis from the out-of-plane c axis to the ab-plane. The room-temperature x-ray magnetic circular dichroism signal is enhanced from 0% to 9% at an implantation level of 10−2 Ga+·Å−3. These results provide new opportunities for tailoring the magnetic properties of vdW materials beyond room temperature.

The advent of van der Waals (vdW) ferromagnetic (FM) and antiferromagnetic (AFM) materials offers unprecedented opportunities for spintronics and magneto-optic devices. Combining magnetic Kerr microscopy and density functional theory calculations, the AFM-FM transition is investigated and a surprising abnormal magneto-optic anisotropy in vdW CrSBr associated with different magnetic phases (FM, AFM, or paramagnetic state) is discovered. This unique magneto-optic property leads to different anisotropic optical reflectivity from different magnetic states, permitting direct imaging of the AFM Néel vector orientation and the dynamic process of the AFM-FM transition within a magnetic field. Using Kerr microscopy, not only the domain nucleation and propagation process is imaged but also the intermediate spin-flop state in the AFM-FM transition is identified. The unique magneto-optic property and clear identification of the dynamics process of the AFM-FM phase transition in CrSBr demonstrate the promise of vdW magnetic materials for future spintronic technology.

2D magnets have recently drawn enormous interest. As an air‐stable A‐type van der Waals antiferromagnet (AFM), CrSBr has attracted great attention but has also led to controversies about its large‐span ordering temperatures. Herein, a systematic study of the magnetic phase transition in single‐crystalline CrSBr with ultrahigh‐quality through surface‐sensitive X‐ray magnetic linear dichroism and X‐ray magnetic circular dichroism measurements combined with vibrating sample magnetometry for characterization of bulk magnetization is reported. The interlayer AFM order of both surface and bulk CrSBr is revealed to maintain a similar Néel temperature within the range of 132–142 K. However, the intralayer ferromagnetic (FM) order of surface CrSBr is found to sustain up to ≈238 K, 70 K higher than the value obtained from the bulk CrSBr, demonstrating a dramatically different surface and bulk Curie temperature in CrSBr. Moreover, a half‐filled t2g electronic state for Cr3+ ions with magnetic moment of ≈3 µB/Cr in CrSBr is clearly identified. These results enrich the understanding of the electronic structure and magnetism in CrSBr, providing this material as a promising building block for future spintronic devices. [ABSTRACT FROM AUTHOR]

The advent of van der Waals (vdW) ferromagnetic (FM) and antiferromagnetic (AFM) materials offers unprecedented opportunities for spintronics and magneto‐optic devices. Combining magnetic Kerr microscopy and density functional theory calculations, the AFM‐FM transition is investigated and a surprising abnormal magneto‐optic anisotropy in vdW CrSBr associated with different magnetic phases (FM, AFM, or paramagnetic state) is discovered. This unique magneto‐optic property leads to different anisotropic optical reflectivity from different magnetic states, permitting direct imaging of the AFM Néel vector orientation and the dynamic process of the AFM‐FM transition within a magnetic field. Using Kerr microscopy, not only the domain nucleation and propagation process is imaged but also the intermediate spin‐flop state in the AFM‐FM transition is identified. The unique magneto‐optic property and clear identification of the dynamics process of the AFM‐FM phase transition in CrSBr demonstrate the promise of vdW magnetic materials for future spintronic technology. [ABSTRACT FROM AUTHOR]

The creation of van der Waals (vdW) ferromagnets with tunable Curie temperature (TC) and magnetic anisotropy is essential in developing vdW magnet-based devices. Here, we report an effective and reliable method for modulating the magnetic properties of vdW Fe5GeTe2 by site-specific Ga+ implantation. In this study, we report an easy axis in the ab-plane for bulk Fe5GeTe2 (TC = 310 K) and an axis out of the plane for thin Fe5GeTe2 flakes (TC = 290 K). Combining element-resolved photoemission electron microscopy and spatially resolved magneto-optic Kerr microscopy, we find that the implantation of a tiny amount of 10−3 Ga+·Å−3 in Fe5GeTe2 greatly enhances the TC from 290 to 360 K and switches the magnetic easy axis from the out-of-plane c axis to the ab-plane. The room-temperature x-ray magnetic circular dichroism signal is enhanced from 0% to 9% at an implantation level of 10−2 Ga+·Å−3. These results provide new opportunities for tailoring the magnetic properties of vdW materials beyond room temperature. [ABSTRACT FROM AUTHOR]

An experimental plot in Chenggong District of Kunming was polluted by artificial addition of Pb and Cd, which was divided mto Pb addition group and Cd addition group to study the relationship between soil magnetic parameters and heavy metal concentrations. The single-factor pollution index and Nemeiro comprehensive pollution index were used for pollution evaluation. The results showed that the experimental plots were heavily polluted by Pb and Cd,and Cu,Zn, As,Cr and Hg were slightly to moderately polluted. Using Pearson correlation and principal component analysis methods to explore the relationship between sol magnetic parameters (low frequency mass magnetic susceptibly --f, frequency mass magnetic susceptibility -- fd%, nondysteresss remanence ARM, saturation isothermal remanence SIRM) and heavy metal content under artificial Pb and Cd pollution conditions relationship. --lf n each control group showed a significant positive correlation WILL Cu and Zn. In the Pb addition group, SIRM was significantly negatively correlated with Pb concentration, and in the Cd addition group, --fd% was significantly positively correlated WILL Cd concentration. [ABSTRACT FROM AUTHOR]

Increasing forest soil organic carbon (SOC) storage is important for reducing carbon dioxide (CO2) emissions from terrestrial ecosystems and mitigating global climate change. Although the effects of altitude, temperature and rainfall on organic carbon have been studied extensively, it is difficult to increase SOC storage by changing these factors in actual forest management. This study determined the SOC, soil physical and chemical properties, nutrient elements, heavy metal elements, soil minerals and microbial biomass in the 0–140‐cm soil layer of the monsoon broad‐leaved forest in the acid red soil region of southwestern China by stratification. We tried to identify the soil factors affecting the SOC storage of the forest in the acid red soil region and determine the weights of the factors affecting the SOC, with the aim of improving the SOC retention capacity in forest management by changing the main soil factors affecting SOC storage. The results showed that the soil factors affecting the forest SOC storage in this area are total nitrogen (N, 22.7%) > soil water content (19.9%) > active iron (including poorly crystalline iron, Feo, 15.5%) > pH (9.5%) > phosphorus (P, 9.4%) > aluminium (Al, 8.9%) > silicon (Si, 7.1%) > sulphur (S, 6.8%). Of these factors, N, the water content, Feo, and P are practical factors for forest management, whereas the pH, Al, Si and S are not. SOC was significantly positively correlated with the soil N concentration, water content, active iron content and P concentration (p <.05). In acidic red soil areas, with active iron as the highlight, N, soil water content, phosphorus and active iron jointly regulate the forest SOC storage capacity. Consequently, in actual forest management, any measures to promote soil N and water content and to activate inactive iron can enhance the storage of SOC, as appropriate input of N and P fertiliser and irrigation in dry years and the dry season. Highlights: The soil environmental factors affecting SOC storage in forest soil are quantifiedActivation of inactive iron helps SOC storage in forest soilIrrigation and N and P input are effective for helping SOC storage in forest soilN, WC, P and Feo jointly regulate SOC in tropical acid red soil forest [ABSTRACT FROM AUTHOR]

Soil erosion continues to be one of the world's biggest environmental problems. The information on erosion process, the spatially-distributed erosion and deposition is the key to develop soil erosion prediction models that can provide a scientific basis for soil and water conservation planning. However, conventional erosion monitoring techniques did not provide enough such information. Numerous trace materials have been applied in recent decades and been successfully utilized in soil erosion research and rare earth elements (REEs) were considered as ideal tracer materials due to their special properties. The development and improvement process of REE trace method is summarized briefly in this paper. The applications of REE trace method in studying the erosion process and the spatial distribution of erosion and deposition from slope and watershed are systematically reviewed; and its application in revealing soil erosion mechanism is also overviewed. The systematic review on REE trace method in this paper could provide scientific references for understanding the REE trace method and extending its application in wider research areas. [ABSTRACT FROM AUTHOR]

Based on the fuzzy AHP method, an evaluation index system for eco-restoration engineering on the slope of a hydropower project is established with twenty indexes, which can combine qualitative analysis and quantitative analysis. It includes four kinds of indexes which are the effect of soil and water conservation, the effect of habitat material improvement, the effect of ecology and the effect of landscape. According to the problems found through the analysis, five targeted regulatory technologies were developed and then applied to eco-restoration engineering on the slopes of the Guangzhao, Nuozu, Xiaowan, Xiangjiaba and Pubugou hydropower stations, respectively. And the eco-regulation measures have effectively solved the existing problems. Through eco-regulation, the evaluation result of each has greatly increased and these measures have clearly improved the current conditions of the five typical engineering cases. This shows that the regulatory technologies are effective and that the evaluation index system is applicable. [ABSTRACT FROM AUTHOR]

TiO2/CeO2 composite catalysts were successfully prepared with hydrothermal and deposition-precipitation method. Acquired samples were characterized with diversiform analytical techniques and spectroscopy to ensure their structure, morphology, and light absorption properties. The results manifest that all the samples contain highly crystalline anatase phase. X-ray diffraction (XRD) and scanning electron microscope (SEM) show that the addition of CeO2 inhibited the grain growth without destroying the original appearance, and the inhibition effect of hydrothermal method is more obvious. Structure of the hole was explained combined with the mechanism of reaction. Experimental consequences such as Raman and photoluminescence (PL) spectrum peaks broadening and movement further indicate that CeO2 have been composite with the TiO2 and caused size effect. Compared to the pure TiO2, we can see from the UV-Vis spectrum that the band gap of TiO2/CeO2 is narrower, and the light absorption range is slightly expanded to visible light, which will be hopeful to enhance the photoconversion efficiency. [ABSTRACT FROM AUTHOR]

Scientific assessment of soil quality is the foundation of sustainable vegetation eco-restoration in engineering disturbed areas. This study aimed to find a qualitative and comprehensive method for assessing soil quality after vegetation eco-restoration in engineering disturbed areas. Sixteen soil indicators were used at six vegetation eco-restoration sites as the potential soil indicators. A minimum data set (MDS) and revised minimum data set (RMDS) were determined by principal component analysis. Six soil quality indices (SQIs) of varying scoring functions based on different data sets were employed in this study. Significant positive correlations were observed among all six SQIs, indicating that the effects of different vegetation eco-restoration measures on soil quality could be quantified by all six SQIs. The SQI values of the vegetation concrete eco-restoration slope (VC), frame beam filling soil slope (FB), thick layer base material spraying slope (TB), and external-soil spray seeding slope (SS) were all significantly higher than the SQI value of the abandoned slag slope (AS). It is noteworthy that the SQIs of the VC and TB sites were also significantly higher than the SQI of the natural forest (NF) site. These results indicate that the application of artificial remediation measures can significantly improve the soil quality of the disturbed area at the Xiangjiaba hydropower station. The results of this study also indicate that the SQI-NLRM method is a practical and accurate quantitative tool for soil quality assessment and is recommended for evaluating soil quality under various vegetation eco-restoration techniques in disturbance areas at the Xiangjiaba hydropower station and in other areas with similar habitat characteristics., Competing Interests: The authors declare that they have no competing interests., (© 2024 Zhao et al.)

Background: Medullary thyroid carcinoma (MTC) is a rare but aggressive endocrine malignancy that originates from the parafollicular C cells of the thyroid gland. Enhancer RNAs (eRNAs) are non-coding RNAs transcribed from enhancer regions, which are critical regulators of tumorigenesis. However, the roles and regulatory mechanisms of eRNAs in MTC remain poorly understood. This study aims to identify key eRNAs regulating the malignant phenotype of MTC and to uncover transcription factors involved in the regulation of key eRNAs., Methods: GSE32662 and GSE114068 were used for the identification of differentially expressed genes, eRNAs, enhancers and enhancer-regulated genes in MTC. Metascape and the transcription factor affinity prediction method were used for gene function enrichment and transcription factor prediction, respectively. qRT-PCR was used to detect gene transcription levels. ChIP-qPCR was used to assess the binding of histone H3 lysine 27 acetylation (H3K27ac)-enriched regions to anti- H3K27ac. RIP-qPCR was used to detect the binding between FOXQ1 and LINC00887. CCK8 and Transwell were performed to measure the proliferation and invasion of MTC cells, respectively. Intracellular reactive oxygen species (ROS) levels were quantified using a ROS assay kit., Results: Four eRNAs (H1FX-AS1, LINC00887, MCM3AP-AS1 and A1BG-AS1) were screened, among which LINC00887 was the key eRNA promoting the proliferation and invasion of MTC cells. A total of 135 genes controlled by LINC00887-regulated enhancers were identified; among them, BCL2, PRDX1, SFTPD, TPO, GSS, RAD52, ZNF580, and ZFP36L1 were significantly enriched in the "ROS metabolic process" term. As a transcription factor regulating genes enriched in the "ROS metabolic process" term, FOXQ1 could recruit LINC00887. Overexpression of FOXQ1 restored LINC00887 knockdown-induced downregulation of GSS and ZFP36L1 transcription in MTC cells. Additionally, FOXQ1 overexpression counteracted the inhibitory effects of LINC00887 knockdown on the proliferation and invasion of MTC cells and the promotion of intracellular ROS accumulation induced by LINC00887 knockdown., Conclusion: LINC00887 was identified as a key eRNA promoting the malignant phenotype of MTC cells. The involvement of FOXQ1 was essential for LINC00887 to play a pro-tumorigenic role in MTC. Our findings suggest that the FOXQ1/LINC00887 axis is a potential therapeutic target for MTC., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)