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1.
J Phys Condens Matter ; 36(35)2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38806048

ABSTRACT

Recently, signatures of superconductivity with critical temperature from 20 to 30 K have been reported in pressured trilayer nickelate La4Ni3O10through a pressure-induced structure transition. Here we explore the evolution of electronic structures and electronic correlations in different phases of La4Ni3O10under corresponding pressure regions, by using density functional theory (DFT) combined with dynamical mean-field theory (DMFT). Similar to bilayer superconductor La3Ni2O7, the electronic bands in superconducting La4Ni3O10are dominated by Ni-3dx2-y2and 3dz2orbits near the Fermi level, in contrast, the inner Ni-O plane in La4Ni3O10generates a doublet hole-pocket Fermi surfaces around the Brillouin-zone corner, meanwhile one branch of the Ni-3dz2bands is pushed very close above the Fermi level, which can induce an electron pocket through small electron doping. The DFT+DMFT simulations suggest that the electronic correlations only give minor modification to the Fermi surfaces, meanwhile the Ni-3dz2and 3dx2-y2states on outer Ni-O layers have considerable greater mass enhancements than on the inner layer. The sensitiveness of electronic structure under doping and unique layer dependence of correlation suggest a distinct superconducting mechanism with respect to bilayer La3Ni2O7. Based on the DFT and DFT+DMFT simulations, we eventually derive a trilayer effective tight-binding model, which can produce rather precise electronic bands and Fermi surfaces, hence can serve as an appropriate model to further study the superconducting mechanism and paring symmetry in trilayer La4Ni3O10.

2.
PeerJ ; 12: e17223, 2024.
Article in English | MEDLINE | ID: mdl-38618573

ABSTRACT

Background: The beet armyworm, Spodoptera exigua (Hübner), is an important agricultural pest worldwide that has caused serious economic losses in the main crop-producing areas of China. To effectively monitor and control this pest, it is crucial to investigate its population dynamics and seasonal migration patterns in northern China. Methods: In this study, we monitored the population dynamics of S. exigua using sex pheromone traps in Shenyang, Liaoning Province from 2012 to 2022, combining these data with amigration trajectory simulation approach and synoptic weather analysis. Results: There were significant interannual and seasonal variations in the capture number of S. exigua, and the total number of S. exigua exceeded 2,000 individuals in 2018 and 2020. The highest and lowest numbers of S. exigua were trapped in September and May, accounting for 34.65% ± 6.81% and 0.11% ± 0.04% of the annual totals, respectively. The average occurrence period was 140.9 ± 9.34 days during 2012-2022. In addition, the biomass of S. exigua also increased significantly during these years. The simulated seasonal migration trajectories also revealed varying source regions in different months, primarily originated from Northeast China and East China. These unique insights into the migration patterns of S. exigua will contribute to a deeper understanding of its occurrence in northern China and provide a theoretical basis for regional monitoring, early warning, and the development of effective management strategies for long-range migratory pests.


Subject(s)
Agriculture , Humans , Animals , Spodoptera , Seasons , Population Dynamics , China/epidemiology
3.
Fa Yi Xue Za Zhi ; 39(1): 18-26, 2023 Feb 25.
Article in English, Chinese | MEDLINE | ID: mdl-37038851

ABSTRACT

OBJECTIVES: To realize the dynamic visualization of forensic odontology based on the bibliometrics methods, and capture the research hotspots and identify the future development trend. METHODS: Literature articles published from January 1995 to December 2020 were searched according to specific subject words in the core data set of Web of Science. The visualization analysis of publishing country, institution, discipline, author, co-cited journal and keywords was performed by CiteSpace 5.7.R5W software. RESULTS: The annual analysis of publications showed an upward trend of forensic odontology research literature year by year, with the number of annual publications more than 110 in the last five years. Developed countries were the main source of contributions and the average centrality was greater than 0.2. The research of forensic odontology involved multiple disciplines, including stomatology, biology, computer science and medical imaging, with a distinct interdisciplinary feature. A total of 115 nodes were obtained by keyword cluster analysis. The principal line of forensic odontology mainly included individual identification and age estimation and the emergence of hotspots was closely related to new technologies. Population-based odontology investigation, improvement of traditional dental age estimation method and dental age estimation based on new technology were popular research in forensic odontology. CONCLUSIONS: Developing countries urgently need to increase the focus on related research. It may be an important direction for the development of forensic odontology to establish and enrich the regional dental database, develop new odontology identification technology combined with frontier and high-end technology, and develop the identification program based on advanced information technology.


Subject(s)
Forensic Medicine , Software , Bibliometrics
4.
Front Aging Neurosci ; 14: 1036120, 2022.
Article in English | MEDLINE | ID: mdl-36483116

ABSTRACT

Background: Recently, research on the microbiota-gut-brain axis (MGBA) has received increasing attention, and the number of studies related to Alzheimer's disease (AD) has increased rapidly, but there is currently a lack of summary of MGBA in AD. Objective: To capture research hotspots, grasp the context of disciplinary research, and explore future research development directions. Methods: In the core dataset of Web of Science, documents are searched according to specific subject words. CiteSpace software is used to perform statistical analysis on measurement indicators such as the number of published papers, publishing countries, institutions, subject areas, authors, cocited journals, and keywords, and to visualize of a network of relevant content elements. Results: The research of MGBA in AD has shown an upward trend year by year, and the cooperation between countries is relatively close, and mainly involves the intersection of neuroscience, pharmacy, and microbiology. This research focuses on the relationship between MGBA and AD symptoms. Keyword hotspots are closely related to new technologies. Alzheimer's disease, anterior cingulate cortex, inflammatory degeneration, dysbiosis, and other research are the focus of this field. Conclusion: The study revealed that the research and development of MGBA in AD rapidly progressed, but no breakthrough has been made in the past decade, it still needs to be closely combined with multidisciplinary technology to grasp the frontier hotspots. Countries should further strengthen cooperation, improve the disciplinary system, and increase the proportion of empirical research in all research.

5.
Chaos ; 31(3): 033123, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33810733

ABSTRACT

The structure of a social network plays a crucial role for dynamic analysis, which is invisible in most scenes. In this paper, we present a model for reconstructing the social network by taking into account the public opinion diffusion dynamic model for specific agenda. First, the initial polarity attitude of users i for the agenda, oi, is set in the range [-1,1], where negative and positive attitudes are set as -1 and 1, respectively, while 0 means that user i's attitude is uncertain. Second, we present an optimization model for detecting the relationship among each pair of users based on the generated public observable information. The experimental results for four synthetic networks and three real-world social networks show that the reconstruction accuracy depends on the uncertainty of the initial attitudes greatly. This work is helpful for revealing the structure of social networks in terms of public information.

6.
Ying Yong Sheng Tai Xue Bao ; 31(2): 625-633, 2020 Feb.
Article in Chinese | MEDLINE | ID: mdl-32476357

ABSTRACT

We isolated bacteria from the phycosphere of Scenedesmus obliques and sequenced 16S rDNAs to establish algae-bacterial co-culture systems. Further, we examined effects of the bacteria on algal growth, and parameters associated with physio-biochemical and oil-producing characteristics of S. obliquus. Seven bacterial strains were isolated, including Micrococcus (strains 1-1, 1-2 and 1-3), Pseudomonas sp. (strains 2-1 and 2-2), Exiguobacterium (strain-3) and Staphylococcus sp. (strain-4). Among them, two bacteria (strain 1-2 and strain 2-1) were characterized as the dominant growth-promoting bacterial strains, which significantly increased algal growth, pigment production, and oil enrichment. After eight days cultivation under microalgal-bacterial (strain 1-2) symbiotic systemat at an initial ratio of 1:10, biomass of S. obliquus was 4.27 g·L-1, about 46.0% higher than that of the control. The contents of chlorophyll a, chlorophyll b and carotenoids were increased by 12.1%, 16.7% and 25.0%, respectively. Oil content was increased by 14.0% and reached to 25.7%, and the oleic acid content was significantly higher than that of the control and up to 16.4%. When co-cultured with Pseudomonas sp. (strain 2-1) for eight days at an initial ratio of 1:5, algal biomass, chlorophyll a, chlorophyll b and carotenoids contents were higher than that of the control by 47.9%, 16.0%, 17.5% and 19.9%, respectively. The total oil (27.1%) and oleic acid (18.2%) contents were increased by 20.4% and 64.0%, respectively. We concluded that Micrococcus (strain 1-2) and Pseudomonas sp. (strain 2-1) could significantly promote algal growth and increase oil production by their beneficial interaction with S. obliques, which could be potentially used in commercial production of S. obliques.


Subject(s)
Microalgae , Scenedesmus , Bacteria , Biomass , Chlorophyll A
7.
J Mater Chem B ; 6(6): 961-965, 2018 Feb 14.
Article in English | MEDLINE | ID: mdl-32254376

ABSTRACT

A facile and controllable method for one-step synthesis of small-sized monodisperse fluorescent-magnetic bifunctional microparticles based on droplet splitting and photopolymerization was established. Using this method, magnetic nanoparticles and acryloyl rhodamine B (acryloyl-RhB) molecules were incorporated into the dispersed phase, which allowed the direct generation of functional microparticles. Functional microparticles with diameters in the range of 2.8 to 19.2 µm were obtained by controlling the fluidic characteristics. The fluorescence intensity of the microparticles could be regulated by adjusting the concentration of the acryloyl-RhB molecule in the dispersed phase. Furthermore, the fluorescent-magnetic bifunctional microparticles were successfully used to detect proteins specifically by ratiometric fluorescence analysis, showing their potential in biological sample detection.

8.
Lab Chip ; 18(1): 41-56, 2017 12 19.
Article in English | MEDLINE | ID: mdl-29098217

ABSTRACT

In recent years, a broad range of nanocrystals have been synthesized in droplet-based microfluidic reactors which provide obvious advantages, such as accurate manipulation, better reproducibility and reliable automation. In this review, we initially introduce general concepts of droplet reactors followed by discussions of their main functional regions including droplet generation, mixing of reactants, reaction controlling, in situ monitoring, and reaction quenching. Subsequently, the enhanced mass and heat transport properties are discussed. Next, we focus on research frontiers including sequential multistep synthesis, intelligent synthesis, reliable scale-up synthesis, and interfacial synthesis. Finally, we end with an outlook on droplet reactors, especially highlighting some aspects such as large-scale production, the integrated process of synthesis and post-synthetic treatments, automated droplet reactors with in situ monitoring and optimizing algorithms, and rapidly developing strategies for interfacial synthesis.

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