High-throughput methods were developed to prepare multicomponent NbSi based (NbxCryTizSi1-x-y-zAl0.5) alloy film combinatorial libraries (x = 0 → 0.95, y = 0 → 0.95-x, z = 0 → 0.95-x-y) with ...composition gradients. Oxidation behavior of the as-deposited film was investigated in dry air at 1250 °C. The results show that the as-deposited film is consisted of a mixture of amorphous and crystalline phases. Crystallized film is composed Cr2Nb, Nb5Si3 and Nbss phases after annealing. The film after oxidation at 1250 °C for different times exhibits three regions of distinct oxidation behavior. The composition for establishment of a protective CrNbO4 scale across the entire film is determined rapidly.
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•NbSiNb-Si based alloy film combinatorial libraries with composition gradients were prepared by high-throughput method.•Crystallized film is composed of Cr2Nb, Nb5Si3 and Nbss phases after annealing.•Three distinct regions of oxides (CrNbO4, CrNbO4 + Nb2O5 + TiNb2O7, Nb2O5 + TiNb2O7) are identified across oxidized film.•Composition for establishment of a protective CrNbO4 scale is determined rapidly.
Orchidaceous plant Dendrobium genus is often used as a tonic, and its phenolic components have attracted attention for its anti-tumor and anti-diabetic complications. Bibenzyls is one of the ...essential phenolic active ingredients in the Dendrobium genus. At present, 89 bibenzyl derivatives have been extracted and identified from 46 Dendrobium species. The activity studies have shown that 42 compounds have pharmaceutical activity. Among them, 23 compounds showed antitumor activity; 7 compounds showed anti-diabetes and its complications activity; 10 compounds exhibited neuroprotective effects; 18 compounds showed antioxidant effects; 11 compounds had anti-inflammatory activity; 3 compounds had Antiplatelet aggregation effects; 3 compounds had antibacterial and antiviral effects. The Bibenzyls is small-molecular compounds of natural origin and widely sourced. Previous studies showed that the bibenzyls has good anti-tumor, anti-diabetes and its complications, and neuroprotective effects, and it has great potential for treating tumors, diabetes and its complications, Alzheimer’s disease (AD) and Parkinson’s disease (PD). Additionally, compounds such as moscatilin (1), gigantol (2) and chrysotoxine (3) have been further studied as lead compounds, and compounds exhibited therapeutical effects had been synthesized. Enough pieces of evidences have shown that the Bibenzyls have good development prospects. This article reviews the pharmacological effects of bibenzyls in Dendrobium species and provides an idea for its further development.
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•It includes all the bibenzyls in Dendrobium species and the status of its pharmacological studies.•It involves a large number of the mechanisms of bibenzyls, which provides a basis for the further study of these compounds.•Bibenzyls has definite multi-target inhibitory activity, which lays a foundation for the research of multi-target inhibitors.
Terpenes, especially volatile terpenes, are important components of tea aroma due to their unique scents. They are also widely used in the cosmetic and medical industries. In addition, terpene ...emission can be induced by herbivory, wounding, light, low temperature, and other stress conditions, leading to plant defense responses and plant-plant interactions. The transcriptional levels of important core genes (including
,
, and
) involved in terpenoid biosynthesis are up- or downregulated by the MYB, MYC, NAC, ERF, WRKY, and bHLH transcription factors. These regulators can bind to corresponding cis-elements in the promoter regions of the corresponding genes, and some of them interact with other transcription factors to form a complex. Recently, several key terpene synthesis genes and important transcription factors involved in terpene biosynthesis have been isolated and functionally identified from tea plants. In this work, we focus on the research progress on the transcriptional regulation of terpenes in tea plants (
) and thoroughly detail the biosynthesis of terpene compounds, the terpene biosynthesis-related genes, the transcription factors involved in terpene biosynthesis, and their importance. Furthermore, we review the potential strategies used in studying the specific transcriptional regulation functions of candidate transcription factors that have been discriminated to date.
With the evolution of the sixth generation (6G) mobile communication technology, the terahertz (THz) spectrum has attracted much attention in wireless communication applications due to its high ...bandwidth and low signal transmission delay. However, the introduction of the THz spectrum leads to higher path transmission losses and complex signal attenuation. This makes user sensing and localization in THz massive multiple-input multiple-output (MIMO) systems more challenging. In this paper, we investigate the user sensing and localization problem in THz massive MIMO systems with the assistance of reconfigurable intelligent surfaces (RIS). Firstly, the received signal is modeled as a tensor, and a parallel factor (PARAFAC) method is proposed. The minimum description length (MDL) is then utilized to detect the number of scattering paths in the channel. On this basis, the alternating least squares (ALS) algorithm is employed to estimate the factor matrices, followed by the utilization of a straightforward correlation-based approach to obtain channel parameter information. Finally, the positions of users and scattering points are estimated based on the geometric relationship between channel parameters and location coordinates. The simulation results have verified the effectiveness of the proposed scheme compared to the existing competitive algorithms, and indicate that the proposed scheme exhibits superior parameter estimation performance and can achieve localization accuracy at the decimeter level.
Utilizing unmanned aerial vehicle (UAV) technology in communication holds promise for meeting the increasing data rate demands in future wireless systems due to its flexibility. Meanwhile, ...reconfigurable intelligent surface (RIS) has garnered increased attention for their potential to enhance wireless communication performance through intelligent control of the transmission environment. In this paper, we first combine the UAV and the RISs to construct an Internet of Things (IoT) uplink transmission system, where the UAV serves as an aerial relay to collect data from IoT terminal (IT) and forward it to base stations (BS), while RISs assist communication to reduce congestion. Then, a parallel factor (PARAFAC) tensor model is formulated at the BS. At last, the iterative alternating least squares (ALS) algorithm and the closed-form singular value decomposition (SVD) algorithm are derived to fit the constructed tensor model for joint channel estimation and symbol detection. Compared with the competitive algorithms, the two proposed algorithms offer lower computational complexity and superior channel estimation performance. Furthermore, the proposed algorithms exhibit good symbol detection capabilities even at higher transmission rates. The numerical results demonstrate the effectiveness of the proposed algorithms.
The effect of Ge modification on the oxidation of NbSi2 was performed by using the first-principles method based on Density Functional Theory (DFT). The O2 molecule absorption configurations on the ...ideal NbSi2 (001) surface with and without Ge substitution was constructed to study the initial oxidation behavior as well as oxygen diffusion in the bulk NbSi2 cell in the late oxidation stage. Ge substitution was found to decrease the absorption energy of O2 molecule on the NbSi2 (001) surface and therefore reduce the oxidation rate in the initial oxidation stage. The further linear synchronous transit (LST) calculation revealed that Ge substitution increased the energy barrier of O atom diffusion in the bulk NbSi2 cell and decreased the oxidation rate in the late stage.
The effect of Ge modification on the oxidation of NbSi2 was studied by using the first-principles method based on Density Functional Theory (DFT). It was found that Ge substitution decreased the absorption energy of O2 molecule on the NbSi2 (001) surface and increased the energy barrier of O atom diffusion in the bulk NbSi2 cell, and therefore reduce the oxidation rate of NbSi2. Display omitted
1.The effect of Ge modification on NbSi2 oxidation is investigated by first-principles simulation.2.Ge substitution decreased the absorption energy of O2 molecule on the ideal NbSi2 (001) surface.3.Ge substitution increased the activated energy of oxygen diffusion in the bulk NbSi2 cell.
Diflubenzuron is an insecticide that serves as a chitin inhibitor to restrict the growth of many harmful larvae, including mosquito larvae, cotton bollworm and flies. The residue of diflubenzuron is ...often detected in aquaculture, but its potential toxicity to aquatic organisms is still obscure. In this study, zebrafish embryos (from 6 h to 96 h post-fertilization, hpf) were exposed to different concentrations of diflubenzuron (0, 0.5, 1.5, 2.5, 3.5 and 4.5 mg/L), and the morphologic changes, mortality rate, hatchability rate and average heart rate were calculated. Diflubenzuron exposure increased the distance between the venous sinus and bulbar artery (SV-BA), inhibited proliferation of myocardial cells and damaged vascular development. In addition, diflubenzuron exposure also induced contents of reactive oxygen species (ROS) and malondialdehyde (MDA) and inhibited the activity of antioxidants, including SOD (superoxide dismutase) and CAT (catalase). Moreover, acridine orange (AO) staining showed that diflubenzuron exposure increased the apoptotic cells in the heart. Q-PCR also indicated that diflubenzuron exposure promoted the expression of apoptosis-related genes (bax, bcl2, p53, caspase3 and caspase9). However, the expression of some heart-related genes were inhibited. The oxidative stress-induced apoptosis damaged the cardiac development of zebrafish embryos. Therefore, diflubenzuron exposure induced severe cardiotoxicity in zebrafish embryos. The results contribute to a more comprehensive understanding of the safety use of diflubenzuron.
A high-throughput method was applied to study oxidation behavior of Nb–Si based alloy using composition spread alloy film as combinatorial libraries. An extended range of composition gradients of ...Nb–Si based alloy film was deposited by (multi)magnetron co-sputtering. The as-deposited film was composed of amorphous phase. Cr2Nb, Nb5Si3 and Nbss could be detected after annealing treatment. After oxidation at 1250 °C for 10 min and 20 min, the film composition space was divided into three regions of the distinct oxide scales. The compositions for establishment of the different oxides on Nb–Si based alloy was defined efficiently across the entire composition space by the combinatorial libraries.
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•An extended composition range of Nb–Si based alloy film was deposited by high-throughput methods.•Three regions of distinct oxidation behavior (Cr2O3, CrNbO4, Nb2O5 + TiNb2O7) can be observed.•Influence law of wide composition range of Cr on oxidation behavior of Nb–Si based alloy can be elucidated.
Post-translational modifications (PTMs), such as phosphorylation and ubiquitination,
, have been reported to modulate the activities of IRF3 and IRF7. In this study, we found an acetyltransferase ...KAT8 in grass carp (
KAT8, MW286472) that acetylated IRF3/IRF7 and then resulted in inhibition of IFN 1 response.
KAT8 expression was up-regulated in the cells under poly I:C, B-DNA or Z-DNA stimulation as well as GCRV(strain 873) or SVCV infection. The acetyltransferase domain (MYST domain) of KAT8 promoted the acetylation of IRF3 and IRF7 through the direct interaction with them. So, the domain is essential for KAT8 function. Expectedly, KAT8 without MYST domain (KAT8-△264-487) was granularly aggregated in the nucleus and failed to down-regulate IFN 1 expression. Subcellular localization analysis showed that KAT8 protein was evenly distributed in the nucleus. In addition, we found that KAT8 inhibited the recruitment of IRF3 and IRF7 to ISRE response element. Taken together, our findings revealed that grass carp KAT8 blocked the activities of IRF3 and IRF7 by acetylating them, resulting in a low affinity interaction of ISRE response element with IRF3 and IRF7, and then inhibiting nucleic acids-induced innate immune response.
As one of the Mex3 family members, Mex3A is crucial in cell proliferation, migration, and apoptosis in mammals. In this study, a novel gene homologous to mammalian Mex3A (named
CiMex3A
, MW368974) ...was cloned and identified in grass carp, which is 1,521 bp in length encoding a putative polypeptide of 506 amino acids. In CIK cells,
CiMex3A
is upregulated after stimulation with LPS, Z-DNA, and especially with intracellular poly(I:C). CiMex3A overexpression reduces the expressions of
IFN1
,
ISG15
, and pro-inflammatory factors
IL8
and
TNFα
; likewise, Mex3A inhibits IRF3 phosphorylation upon treatment with poly(I:C). A screening test to identify potential targets suggested that CiMex3A interacts with RIG-I exclusively. Co-localization analysis showed that Mex3A and RIG-I are simultaneously located in the endoplasmic reticulum, while they rarely appear in the endosome, mitochondria, or lysosome after exposure to poly(I:C). However, RIG-I is mainly located in the early endosome and then transferred to the late endosome following stimulation with poly(I:C). Moreover, we investigated the molecular mechanism underlying CiMex3A-mediated suppression of RIG-I ubiquitination. The results demonstrated that Mex3A truncation mutant (deletion in the RING domain) can still interact physically with RIG-I, but fail to degrade it, suggesting that Mex3A also acts as a RING-type E3 ubiquitin ligase. Taken together, this study showed that grass carp Mex3A can interact with RIG-I in the endoplasmic reticulum following poly(I:C) stimulation, and then Mex3A facilitates the ubiquitination and degradation of RIG-I to inhibit IRF3-mediated innate antiviral immune response.
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