Converting brownmillerite to alternate layers of Oxygen-deficient and conductive nano-sheets with enhanced thermoelectric properties

Introducing large oxygen deficiencies while retaining low resistivity is important for enhancing the overall thermoelectric properties in 3d transition-metal oxides. In this study, a new synthesis route to reconstruct the insulating brownmillerite SrCoO2.5 is adapted. Through a step-by-step nano-blocks modification, a series of highly-conductive layered structures is evolved, which are [Sr2O2H2]0.5CoO2, [Sr2O2]0.4CoO2, and [Sr2CoO3]0.57CoO2, while still retaining considerable Seebeck coefficient (˜100 µV K-1). Coexistence of low resistivity and high oxygen deficiency is realized in the latter two polymorphs by forming a majority of sintered oxygen vacancies in the rock-salt layer and a minority of normal oxygen vacancies in the CoO2 layer. A room-temperature in-plane power factor of 3.6 mW K-2 m-1, power output density of 4.5 W m-2 at a temperature difference of 28 K, and an out-of-plane thermal conductivity of 0.33 W K-1 m-1 are obtained in the [Sr2O2]0.4CoO2 thin film that exhibits the highest oxygen deficiency (d = 2.95), which is on par with Bi2Te3, the benchmark. It is pointed out that proper distribution of oxygen vacancy is essential in tailoring the physical and chemical properties of transition-metal oxides. The sintered/normal oxygen vacancy layer model provides guidance to the exploration of materials with both low electric resistivity and thermal conductivity.Peer ReviewedPostprint (author's final draft

High-conductive protonated layered oxides from H2O vapor-annealed brownmillerites

Protonated 3d transition-metal oxides often display low electronic conduction, which hampers their application in electric, magnetic, thermoelectric, and catalytic fields. Electronic conduction can be enhanced by co-inserting oxygen acceptors simultaneously. However, the currently used redox approaches hinder protons and oxygen ions co-insertion due to the selective switching issues. Here, a thermal hydration strategy for systematically exploring the synthesis of conductive protonated oxides from 3d transition-metal oxides is introduced. This strategy is illustrated by synthesizing a novel layered-oxide SrCoO3H from the brownmillerite SrCoO2.5. Compared to the insulating SrCoO2.5, SrCoO3H exhibits an unprecedented high electronic conductivity above room temperature, water uptake at 250 °C, and a thermoelectric power factor of up to 1.2 mW K-2 m-1 at 300 K. These findings open up opportunities for creating high-conductive protonated layered oxides by protons and oxygen ions co-doping.CC acknowledges support from the Spanish Ministry of Science, Innovation, and Universities under the “Ramón y Cajal” fellowship RYC2018-024947-I.Peer ReviewedPostprint (author's final draft

PCR and Magnetic Bead-Mediated Target Capture for the Isolation of Short Interspersed Nucleotide Elements in Fishes

Short interspersed nucleotide elements (SINEs), a type of retrotransposon, are widely distributed in various genomes with multiple copies arranged in different orientations, and cause changes to genes and genomes during evolutionary history. This can provide the basis for determining genome diversity, genetic variation and molecular phylogeny, etc. SINE DNA is transcribed into RNA by polymerase III from an internal promoter, which is composed of two conserved boxes, box A and box B. Here we present an approach to isolate novel SINEs based on these promoter elements. Box A of a SINE is obtained via PCR with only one primer identical to box B (B-PCR). Box B and its downstream sequence are acquired by PCR with one primer corresponding to box A (A-PCR). The SINE clone produced by A-PCR is selected as a template to label a probe with biotin. The full-length SINEs are isolated from the genomic pool through complex capture using the biotinylated probe bound to magnetic particles. Using this approach, a novel SINE family, Cn-SINE, from the genomes of Coilia nasus, was isolated. The members are 180–360 bp long. Sequence homology suggests that Cn-SINEs evolved from a leucine tRNA gene. This is the first report of a tRNALeu-related SINE obtained without the use of a genomic library or inverse PCR. These results provide new insights into the origin of SINEs

Study on a channel estimation scheme for GGE single antenna interference cancellation technology

The paper studies the downlink of GGE and related single antenna interference cancellation (SAIC) technology.A LMS adaptive channel estimation algorithm is proposed to improve the performance of linear filtering and enhance the capability of interference cancellation.For suppressing the multicell asynchronous interference,an adaptive judgment mechanism is designed in LMS adaptive channel estimations to extend the applicative range of LMS and improve the performance of channel estimation in asynchronous multicell scenarios

Baseline Sensitivity and Resistance of Botrytis cinerea to Penthiopyrad in Hebei Province, China

Tomato gray mold (TGM), caused by Botrytis cinerea, is a destructive disease of greenhouse tomatoes. Its control mainly depends on the application of chemical fungicides. In China, penthiopyrad has been registered for the management of TGM for about 3 years. In this study, the baseline sensitivity of B. cinerea to penthiopyrad was measured based on mycelial growth and spore germination, using 131 wild isolates collected from Hebei Province. The mean EC50 values 1.054 ± 0.633 mg/L (on mycelial growth) and 0.101 ± 0.037 mg/L (on conidia germination) were used as the baseline sensitivity. Isolates (187) of B. cinerea, sampled from eight regions in Hebei province during 2021 and 2022, were used for resistance studies by mycelial growth method. Based on the resistance factor, these isolates were considered: sensitive (=65 isolates), low (=39 isolates), moderate (=38 isolates), and high (=45 isolates) resistance. All 15 isolates from Raoyang were sensitive to penthiopyrad. Four mutation types in the sdhB subunit, namely H272R, N230I, P225F, and P225L, were associated with the resistance to penthiopyrad. A positive cross-resistance was also recorded between penthiopyrad and fluopyram, boscalid, or pydiflumetofen. These results provide useful information on the chemical control of TGM

Photo-electrochemical effects in topological insulator Sb2Te3 thin films

Topological insulators have attracted increased attention owing to their fascinating properties and important applications, such as spintronic devices, quantum computers, and optoelectronic devices. In this study, we demonstrated the photo-electrochemical properties of a typical topological insulator material, Sb2Te3 thin film. Sb2Te3 thin films were grown on a glass substrate using atomic layer deposition subsequently, samples or thin films were characterized using Raman spectroscopy, scanning electron microscopy, X-ray diffraction, and atomic force microscopy. The as-fabricated Sb2Te3 thin films have continuous and coarse surfaces with high crystallization. The photo-electrochemical effects of Sb2Te3 electrodes were observed. We show that the Sb2Te3 films have potential in photocatalytic water splitting application

Reciprocal regulation between RACGAP1 and AR contributes to endocrine therapy resistance in prostate cancer

Abstract Background Endocrine resistance driven by sustained activation of androgen receptor (AR) signaling pathway in advanced prostate cancer (PCa) is fatal. Characterization of mechanisms underlying aberrant AR pathway activation to search for potential therapeutic strategy is particularly important. Rac GTPase-activating protein 1 (RACGAP1) is one of the specific GTPase-activating proteins. As a novel tumor proto-oncogene, overexpression of RACGAP1 was related to the occurrence of various tumors. Methods Bioinformatics methods were used to analyze the relationship of expression level between RACGAP1 and AR as well as AR pathway activation. qRT-PCR and western blotting assays were performed to assess the expression of AR/AR-V7 and RACGAP1 in PCa cells. Immunoprecipitation and immunofluorescence experiments were conducted to detect the interaction and co-localization between RACGAP1 and AR/AR-V7. Gain- and loss-of-function analyses were conducted to investigate the biological roles of RACGAP1 in PCa cells, using MTS and colony formation assays. In vivo experiments were conducted to evaluate the effect of RACGAP1 inhibition on the tumor growth. Results RACGAP1 was a gene activated by AR, which was markedly upregulated in PCa patients with CRPC and enzalutamide resistance. AR transcriptionally activated RACGAP1 expression by binding to its promoter region. Reciprocally, nuclear RACGAP1 bound to the N-terminal domain (NTD) of both AR and AR-V7, blocking their interaction with the E3 ubiquitin ligase MDM2. Consequently, this prevented the degradation of AR/AR-V7 in a ubiquitin-proteasome-dependent pathway. Notably, the positive feedback loop between RACGAP1 and AR/AR-V7 contributed to endocrine therapy resistance of CRPC. Combination of enzalutamide and in vivo cholesterol-conjugated RIG-I siRNA drugs targeting RACGAP1 induced potent inhibition of xenograft tumor growth of PCa. Conclusion In summary, our results reveal that reciprocal regulation between RACGAP1 and AR/AR-V7 contributes to the endocrine resistance in PCa. These findings highlight the therapeutic potential of combined RACGAP1 inhibition and enzalutamide in treatment of advanced PCa

Revealing the Electronic Structure and Optical Properties of CuFeO2 as a p-Type Oxide Semiconductor

Delafossite CuFeO2 is a p-type oxide semiconductor with a band gap of ∼1.5 eV, which has attracted great interests for applications in solar energy harvesting and oxide electronics. However, there are still some discrepancies in the literature regarding its fundamental electronic structure and transport properties. In this paper, we use a synergistic combination of resonant photoemission spectroscopy and X-ray absorption spectroscopy to directly study the electronic structure of well-defined CuFeO2 epitaxial thin films. Our detailed study reveals that CuFeO2 has an indirect and d-d forbidden band gap of 1.5 eV. The top of the valence band (VB) of CuFeO2 mainly consists of occupied Fe 3d states hybridized with Cu 3d and O 2p, and the bottom of the conduction band (CB) is primarily made up of unoccupied Fe 3d states. The localized nature of the Fe 3d states at both CB and VB edges would limit the carrier mobility and the dynamics of photoexcited carriers. In addition, Mg doping at Fe sites in CuFeO2 increases the hole carrier concentration and leads to a gradual shift of the Fermi level toward the VB. These insights into its electronic structure are of fundamental importance for rational designing and improving the performance of CuFeO2 as photocatalysts. </p

Overexpression of Phosphoserine Aminotransferase (<i>PSAT</i>)-Enhanced Cadmium Resistance and Accumulation in Duckweed (<i>Lemna turionifera</i> 5511)

Cadmium (Cd) hampers plant growth and harms photosynthesis. Glutamate (Glu) responds to Cd stress and activates the Ca2+ signaling pathway in duckweed, emphasizing Glu’s significant role in Cd stress. In this study, we overexpressed phosphoserine aminotransferase (PSAT), a crucial enzyme in Glu metabolism, in duckweed. We investigated the response of PSAT-transgenic duckweed to Cd stress, including growth, Glu metabolism, photosynthesis, antioxidant enzyme activity, Cd2+ flux, and gene expression. Remarkably, under Cd stress, PSAT-transgenic duckweed prevented root abscission, upregulated the expression of photosynthesis ability, and increased Chl a, Chl b, and Chl a + b levels by 13.9%, 7%, and 12.6%, respectively. Antioxidant enzyme activity (CAT and SOD) also improved under Cd stress, reducing cell membrane damage in PSAT-transgenic duckweeds. Transcriptomic analysis revealed an upregulation of Glu metabolism-related enzymes in PSAT-transgenic duckweed under Cd stress. Moreover, metabolomic analysis showed a 68.4% increase in Glu content in PSAT duckweed exposed to Cd. This study sheds novel insights into the role of PSAT in enhancing plant resistance to Cd stress, establishing a theoretical basis for the impact of Glu metabolism on heavy metal tolerance in plants