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Controllable Weyl nodes and Fermi arcs from Floquet engineering triple fermions

Physical Review B 2024年第12期110卷 L121118页

作者： Shengpu Huang Fangyang Zhan Xianyong Ding Dong-Hui Xu Da-Shuai Ma Rui Wang Institute for Structure and Function Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics Center of Quantum Materials and Devices

Floquet engineering with periodic driving as a powerful tool for designing desirable topological states has been the subject of intense recent studies. Here, we present the application of Floquet engineering to investigate the evolution of topological triple fermions under irradiation of circularly polarized light (CPL), a phenomenon that currently remains a mystery. By using first-principles calculations and Floquet theorem, we demonstrate that WC-type TiO and its analogs are promising candidates for Floquet engineering of triple fermions. The symmetry analysis reveals that the electric field of CPL can break the specific symmetries, such as the time-reversal symmetry and its combination of spatial symmetries, inducing a transition to a flexibly controllable Weyl semimetallic phase. The survived spatial symmetry, controlled by light, guarantees that the Weyl nodes are located along the high-symmetry line or in high-symmetry planes in momentum space. Our findings focusing on Floquet engineering in realistic materials featured by triple fermions would facilitate both theoretical and experimental interest.

关键词： Electronic structure Topological phases of matter Semimetals First-principles calculations

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Molecular dissection of the genetic architecture of phenology underlying Lupinus hispanicus early flowering and adaptation to winter- or spring sowing

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Scientific Reports 2025年第1期15卷 1-21页

作者： Bielski, Wojciech Surma, Anna Belter, Jolanta Kozak, Bartosz Książkiewicz, Michał Rychel-Bielska, Sandra Department of Gene Structure and Function Institute of Plant Genetics Polish Academy of Sciences Poznan 60-479 Poland Department of Genetics and Plant Breeding Poznań University of Life Sciences Dojazd 11 Poznan 60- 632 Poland Department of Genetics Plant Breeding and Seed Production Wroclaw University of Environmental and Life Sciences Wroclaw 50-363 Poland

Spanish lupin, Lupinus hispanicus Boiss. et Reut. is an untapped grain legume species characterized by moderate frost resistance, tolerance to poor soil and waterlogging, high yield stability, and remarkable seed protein content. It has been recognized as a good candidate for domestication to broaden the palette of crop diversity. One of the key characteristics that need to be precisely addressed during domestication is the vernalization responsiveness of flowering, which is advantageous in autumn sowing due to improved frost tolerance, whilst undesired in spring sowing as it delays flowering. Ahead of L. hispanicus breeding, in the present work, we aimed to recognize existing phenotypic variability of flowering time and vernalization response and to evaluate the genetic architecture of early and late phenology by DArT-seq genotyping and genome-wide association study (GWAS) in world germplasm collection of the species. Controlled environment phenotyping revealed high variability of flowering time and vernalization responsiveness and significant correlations with population structure. DArT-seq genotyping yielded 23 728 highly polymorphic markers distributed extensively across all 26 chromosomes. GWAS identified a number of markers significantly associated with flowering time with or without pre-sowing vernalization, including those overlapping with the two major quantitative trait loci reported previously for white lupin species. Microsynteny-based analysis of the genetic content of L. hispanicus genome regions carrying significantly associated markers highlighted several candidate genes from photoperiodic and vernalization pathways. To summarize, the present study identified germplasm resources for autumn- and spring-sown cultivation of L. hispanicus and provided tools for marker-assisted selection towards required flowering phenology. © The Author(s) 2025.

关键词： Flowering induction GWAS Legume crop Legumes Lupinus hispanicus Vernalization

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Alternative splicing of Pax6 in bovine eye and evolutionary conservation of intron sequences

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BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS 1997年第1期240卷 196-202页

作者： Jaworski, C Sperbeck, S Graham, C Wistow, G Section on Molecular Structure and Function National Eye Institute National Institutes of Health Bethesda Maryland 20892

Pax-g is essential for eye development and for tissue-specific gene expression within the eye. Splicing of an alternative exon (5a) leads to variant DNA binding specificity in Pax6. Here we show that in the mature bovine eye the relative abundance of the alternative Pax6-5a mRNA varies markedly, particularly between the lens and iris. Additional alternative splicing products were identified which may lead to ''domain swapping'' or truncation of Pax6 proteins. Comparison of amphibian (Xenopus) and mammalian (bovine) Pax-6 genes revealed highly conserved intronic sequences flanking exon 5a, including potential lariat sites which may have a role in the mechanism of alternative splicing. (C) 1997 Academic Press.

关键词： Alternative Splicing Conserved Sequence Evolution Molecular Homeodomain Proteins Introns Amino Acid Sequence Animals Base Sequence Cattle Comparative Study DNA-Binding Proteins Eye Proteins Molecular Sequence Data Phylogeny RNA Messenger Xenopus laevis

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Lanthanum-Mediated Enhancement of Low Temperature Hydrogenation Activity and Stability in Nickel Catalyst Supported by Mofs

SSRN

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SSRN 2025年

作者： Gao, Hongyi Liu, Zhiyuan Gao, Yan Wang, Changan Zhang, Yuanjie Yang, Ping Liu, Siqi Chen, Juan Liu, Zhimeng Wang, Jingjing Xu, Xinmeng Wang, Ge Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing Beijing100083 China Shunde Innovation School University of Science and Technology Beijing Shunde528399 China Sinopec Research Institute of Petroleum Processing Co. Ltd SINOPEC Beijing100083 China

The development of low-cost, highly efficient, and durable non-noble metal catalysts for hydrogenation reactions has long posed a significant challenge in the field of catalysis. In this study, we present a novel non-noble metal catalyst, Ni/La NPs@UD, which consists of ultra-small nickel nanoparticles (NPs) modified with lanthanum (La) species and anchored on defective UiO-66 supports, specifically designed for the hydrogenation of dicyclopentadiene (DCPD). The incorporation of La not only enhances the electronic properties of the Ni centers but also facilitates effective electron transfer, promoting the formation of low-coordination, electron-rich Ni active sites that significantly improve hydrogen activation efficiency. Remarkably, at a mild temperature of 70 °C, Ni/La NPs@UD achieved 100% conversion of DCPD with a 99.9% selectivity for THDCPD, rivaling that of noble metal catalysts. Furthermore, the La species not only prevents the agglomeration of Ni NPs through a fencing effect but also mitigates the deposition of inert coke by increasing the density of medium strong basic sites. This dual action significantly prolongs the catalyst's lifespan, as evidenced by its sustained catalytic activity over 10 consecutive cycles. This findings underscore the potential of non-precious metal MOFs-based catalysts in achieving efficient hydrogenation under mild conditions, paving the way for their future application in sustainable chemical processes. © 2025, The Authors. All rights reserved.

关键词： Coke

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INHIBIN-BETA, SOMATOSTATIN, AND ENKEPHALIN IMMUNOREACTIVITIES COEXIST IN CAUDAL MEDULLARY NEURONS THAT PROJECT TO THE PARAVENTRICULAR NUCLEUS OF THE HYPOTHALAMUS

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JOURNAL OF COMPARATIVE NEUROLOGY 1990年第2期291卷 269-280页

作者： SAWCHENKO, PE ARIAS, C BITTENCOURT, JC Laboratory of Neuronal Structure and Function Salk Institute for Biological Studies La Jolla California 92037.

Concurrent and sequential dual immunohistochemical labeling methods were used in combination, along with retrograde tracing techniques, to determine the extent to which inhibin .beta. (***.), somatostatin-28 (SS-28), and enkephalin (ENK) immunoreactivity (IR) might be jointly expressed in neurons centered in the caudal part of the nucleus of the solitary tract (NTS) that project to the paraventricular nucleus of the hypothalamus (PVH). The results indicate that at least 65% of ***.-stained neurons in the NTS also express SS-28 IR, and at least 33% are ENK-positive. At least 25% of the ***. IR population stains positively for all three peptides. A substantial number of cells stained with markers for two, or all three, peptide families, could be retrogradely labeled following tracer deposits centered in the PVH. Prominent ***. and SS-28 IR projections from the caudal medulla to the hypothalamus have been described and include a preferential input to oxytocinergic (OT) compartments of the magnocellular neurosecretory system. The present results suggest that these arise in large measure from a common pool of neurons, a subset of which also shows ENK IR. Implications for the control of OT secretion, and for the processing of sensory information through the NTS, are discussed.

关键词： nucleus of the solitary tract neurosecretion oxytocin

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Dislocation neutralizing in a self-organized array of dislocation and anti-dislocation

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Chinese Physics B 2019年第11期28卷 251-257页

作者： Feng-Lin Deng Xiang-Sheng Hu Shao-Feng Wang Department of Physics and Institute for Structure and Function Chongqing UniversityChongqing 400030China Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China

A one-dimensional(1 D) self-organized array composed of dislocation and anti-dislocation is analytically investigated in the frame of Peierls theory. From the exact solution of the Peierls equation, it is found that there exists strong neutralizing effect that makes the Burgers vector of each individual dislocation in the equilibrium array smaller than that of an isolated dislocation. This neutralizing effect is not negligible even though dislocations are well separated. For example, when the distance between the dislocation and the anti-dislocation is as large as ten times of the dislocation width, the actual Burgers vector is only about 80% of an isolated dislocation. The neutralizing effect originates physically from the power-law asymptotic behavior that enables two dislocations interfere even though they are well separated.

关键词： dislocation array neutralizing exact solution

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THE structure OF THE REGULATORY REGION OF THE RAT L1 (L1RN, LONG INTERSPERSED REPEATED) DNA FAMILY OF TRANSPOSABLE ELEMENTS

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NUCLEIC ACIDS RESEARCH 1988年第19期16卷 9215-9230页

作者： FURANO, AV ROBB, SM ROBB, FT Section on Genomic Structure and Function National Institute of Diabetes and Digestive and Kidney Diseases Bethesda MD 20892.

Here we report the DNA structure of the left 1.5 kb of two newly isolated full length members of the rat Ll DNA family (LlRn, long interspersed repeated DNA). In contrast to earlier isolated rat Ll members, both of these contain promoter-like regions that are most likely full length. In addition, the promoter-like region of both members has undergone a partial tandem duplication. A second internal region of the left end of one of the reported members is also tandemly duplicated. The propensity of the left end of rat Ll elements to undergo this form of genetic rearrangement, as well as other structural features revealed by the present work, is discussed in light of the fact that during evolution the otherwise conserved mammalian Ll DNA families have each acquired completely different promoter-like regions. In an accompanying paper [Nur, I., Pascale, E., and Furano, A.V. (1988) Nucleic Acids Res. 16, submitted], we report that one of the rat promoter-like regions can function as a promoter in rat cells when fused to the Escherichia coli chloramphenicol acyltransferase gene.

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Semiconducting behaviors at epitaxial Ca0.5TaO3 interfaces

arXiv

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arXiv 2025年

作者： Nie, Guangdong Han, Guanghui Huang, Shengpu Wu, Huiyin Wang, Deshun Liu, Kangxi Ding, Hao Tang, Fangdong Peng, Licong Ma, Dashuai Sun, Young Liu, Changjiang Hong, Deshun Department of Applied Physics Chongqing University Chongqing401331 China Center of Quantum Materials and Devices Chongqing University Chongqing401331 China School of Materials Science and Engineering Peking University Beijing100871 China Institute for Structure and Function Department of Physics Chongqing Key Laboratory for Strongly Coupled Physics Chongqing University Chongqing400044 China Department of Physics University at Buffalo SUNY BuffaloNY14260 United States

Emergent phenomena take place in symmetry-breaking systems, notably the recently discovered two-dimensional electron gas and its tunable superconductivities near the KTaO3 interfaces. Here, we synthesized perovskite Ca0.5TaO3 films along both [001] and [111] orientations. Different from the KTaO3 system, Ca0.5TaO3 films show semiconducting behaviors when capped with LaAlO3 films in both [001] and [111] orientations. By growing films at higher temperatures, more oxygen vacancies can be introduced, and the carrier density can be tuned from ~ 1014 cm-2 to ~ 1016 cm-2. Another difference is that the superconducting transition temperature Tc in KTaO3 (111) increases linearly along with its carrier density, while the Ca0.5TaO3 (111) remains semiconducting when carrier density ranges from ~ 1014 cm-2 to ~ 1016 cm-2. Based on the density function theory calculation, Ca0.5TaO3 and KTaO3 show similar electronic band structures. According to the energy-dispersive X-ray spectroscopy, we found heavy Sr diffusion from the substrate to the Ca0.5TaO3 layer, which may destroy the interfacial conductivity. Our work demonstrates that besides the oxygen vacancies, electronic transport is sensitive to the atomic intermixing near the interface in tantulates. © 2025, CC BY.

关键词： Perovskite

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Dislocation energy and Peierls stress: a rigorous calculation from the lattice theory

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中国物理（英文版） 2006年第6期15卷 1301-1309页

作者： Wang Shao-Feng Institute for Structure and Function Chongqing University Chongqing 400044 China

In the classical Peierls-Nabarro (P-N) theory of dislocation, there is a long-standing contradiction that the stable configuration of dislocation has maximum energy rather than minimum energy. In this paper, the dislocation energy is calculated rigorously in the context of the full lattice theory. It is found that besides the misfit energy considered in the classical P-N theory, there is an extra elastic strain energy that is also associated with the discreteness of lattice. The contradiction can be automatically removed provided that the elastic strain energy associated with the discreteness is taken into account. This elastic strain energy is very important because its magnitude is larger than the misfit energy,its sign is opposite to the misfit energy. Since the elastic strain energy and misfit energy associated with discreteness cancel each other, and the width of dislocation becomes wide in the lattice theory, the Peierls energy, which measures the height of the effective potential barrier, becomes much smaller than that given in the classical P-N theory. The results calculated here agree with experimental data. Furthermore, based on the results obtained, a useful formula of the Peierls stress is proposed to fully include the discreteness effects.

关键词： dislocation energy Peierls stress lattice theory

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A reassessment of mammalian alpha A-crystallin sequences using DNA sequencing: Implications for anthropoid affinities of tarsier

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JOURNAL OF MOLECULAR EVOLUTION 1995年第6期41卷 901-908页

作者： Jaworski, CJ Section on Molecular Structure and Function National Eye Institute National Institutes of Health Bethesda MD 28092 USA.

alpha A-crystallin, a major structural protein in the ocular lenses of all vertebrates, has been a valuable tool for molecular phylogenetic studies. This paper presents the complete sequence for human alpha A-crystallin derived from cDNA and genomic clones. The deduced amino acid sequence differs at two phylogenetically informative positions from that previously inferred from peptide composition. This led us to examine the same region of the alpha A-crystallin gene in 12 other mammalian species using direct sequencing of PCR-amplified genomic DNA. New sequences were added to the database, and corrections were made to all anthropoid sequences, defining clear synapomorphies for anthropoids as a clade distinct from prosimians. Within the anthropoids there are further synapomorphies delineating hominoids, Old World monkeys, and New World monkeys. Significantly, sequence revisions and the addition of new sequence for a prosimian, the sifaka, eliminate the previous support for the proposed anthropoid affinities of the tarsier inferred from alpha A-crystallin protein sequences. In addition, DNA sequences provide greater resolution of certain relationships. For example, although they are identical in protein sequence, comparison of DNA sequences clearly separates mouse and the common tree shrew, grouping the tree shrew closer to prosimians. These results show that adding DNA sequences to the to the existing alpha A-crystallin database can enhance its value in resolving phylogenetic relationships.

关键词： alpha A-crystallin Tarser DNA sequencing anthropoid

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