Most state-of-the-art climate models substantially underestimate the near-surface air temperature (SAT) over the Tibetan Plateau (TP), especially for the cold season. While previous studies have ...attributed this cold bias to local factors such as the elevation difference, coarse resolution, and excessive snow cover, this investigation addresses the potential contributions of the systematic bias of tropical sea surface temperature (SST) to the TP cold bias. Experiments with the NCAR Community Atmosphere Model demonstrate that tropical SST bias results in an apparent cold bias over the TP, especially in boreal winter, and explains about 40% of the deviation in multi-model mean SAT over the TP relative to station observations. Forced by the tropical SST bias, heat flux exhibits an anomalous divergence over the plateau, causing a cooling center in the mid- and lower-troposphere over the TP. This atmospheric cooling in turn leads to a reduction of the downward longwave radiative fluxes reaching the surface, less energy supply, and thus a cold bias over the TP.
In this work, oxygen functional groups (OFGs) was introduced into needle coke to increase sodium storage sites (CO) and tailor the interlayer distances from 3.44 to 3.84 Å for Na+ adsorption and ...intercalation. The OFGs are determined precisely using X-ray absorption near-edge structure spectroscopy and thermogravimetric-mass spectrometry. Benefiting from the coordination of fast surface redox reaction kinetics and boosted Na+ intercalation process, the resulting material under optimal oxidization realizes a superior reversible capacity of 385 mA h g−1 at 0.05 A g−1, showing great potentials in the large-scale application for sodium ion batteries anodes.
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•Needle coke (NC) is oxygen-functionalized through a facile strategy.•Oxygen-functionalized NC constitutes “adsorption-intercalation” Na+ storage system.•Oxygen-functionalization endows NC fast adsorption and intercalation kinetics.•The oxygen-functionalized NC realizes a high electrochemical performance.
Microbial transformations, especially the reduction and methylation of Se oxyanion, have gained significance in recent years as effective detoxification methods. Ganoderma lucidum is a typical Se ...enrichment resource that can reduce selenite to elemental Se and volatile Se metabolites under high selenite conditions. However, the detailed biological processes and reduction mechanisms are unclear. In this study, G. lucidum reduced selenite to elemental Se and further aggregated it into Se nanoparticles with a diameter of < 200 nm, simultaneously accompanied by the production of pungent, odorous, and volatile methyl-selenium metabolites. Tandem mass tag-based quantitative proteomic analysis revealed thioredoxin 1, thioredoxin reductase (NADPH), glutathione reductase, 5-methyltetrahydropteroyltriglutamate-homocysteine methyltransferase, and cystathionine gamma-lyase as proteins involved in selenite reduction and methylation. Furthermore, the high expression of proteins associated with cell structures that prompted cell lysis may have facilitated Se release. The upregulation of proteins involved in the defense reactions was also detected, reflecting their roles in the self-defense mechanism. This study provides novel insights into the vital role of G. lucidum in mediating Se transformation in the biogeochemical Se cycle and contributes to the application of fungi in Se bioremediation.
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●Ganoderma lucidum played a vital role in mediating Se transformation and Se cycle in the environment.●Biogenic Se-nanoparticles occurred intracellularly and largely mediated by trxA, trxB and GSR.●The highly expressions of metE, CTH and trxB contributed to the production of 10 types of methyl-selenium metabolites.●The release of Se-nanoparticles in G. lucidum was by the looseness of cell wall and cell membrane structures.
The tumor suppressor p53 is the most frequently mutated gene in human cancer and more than half of cancers contain p53 mutations. The development of novel and effective therapeutic strategies for p53 ...mutant cancer therapy is a big challenge and highly desirable. Ubiquitin‐specific protease 7 (USP7), also known as HAUSP, is a deubiquitinating enzyme and proposed to stabilize the oncogenic E3 ubiquitin ligase MDM2 that promotes the proteosomal degradation of p53. Herein, we report the design and characterization of U7D‐1 as the first selective USP7‐degrading Proteolysis Targeting Chimera (PROTAC). U7D‐1 showed selective and effective USP7 degradation, and maintained potent cell growth inhibition in p53 mutant cancer cells, with USP7 inhibitor showing no activity. These data clearly demonstrated the practicality and importance of PROTAC as a preliminary chemical tool for investigating USP7 protein functions and a promising method for potential p53 mutant cancer therapy.
A first‐in‐class selective USP7 degrader U7D‐1 was developed, inducing potent USP7 degradation in different kinds of cell lines. Importantly, this degrader showed notable anti‐proliferative activities in mutant p53 cancer cells, with USP7 inhibitor having no activity.
Pt/SiO2-Al2O3 catalysts were prepared by the traditional impregnation method (IM) and the strong electrostatic adsorption (SEA) process. Differences in particle size, surface chemical state, Pt ...adsorption site, ammonia oxidation activity, and thermal stability of Pt species were studied systematically. For the fresh catalyst of Pt/SiO2-Al2O3-IM (Pt/SiO2-Al2O3-IM-fresh), Pt species were dispersed unselectively on SiO2-Al2O3, and the large average size (6.6 nm) of Pt species could be observed in a bimodal distribution (ranges of 5.5–6.5 and 8.5–9.5 nm). After the hydrothermal treatment, the Pt size of the aged catalyst (Pt/SiO2-Al2O3-IM-aged) increased significantly, especially Pt particles on SiO2 showed obvious agglomeration and some even increased to 40 nm. Conversely, for the catalyst prepared through the SEA process, Pt species of Pt/SiO2-Al2O3-SEA-fresh were selectively absorbed on Al2O3, the Pt particle size was in the range of 1.5–6.0 nm, and the average particle size was only 2.7 nm. After hydrothermal aging, Pt species did not show obvious agglomeration (the average particle size was 3.2 nm). Above all, Pt/SiO2-Al2O3-SEA presented better catalytic activity and thermal stability than Pt/SiO2-Al2O3-IM, i.e., the temperatures of 50% NH3 conversion for the fresh and aged Pt/SiO2-Al2O3-SEA catalysts were 216 and 223 °C, respectively, much lower than those for Pt/SiO2-Al2O3-IM-fresh (228 °C) and Pt/SiO2-Al2O3-IM-aged (250 °C).
Anderson-Evans type polyoxometalate group (Na6TeW6O24·22 H2O, TeW6) was combined with porous metal-organic framework ZIF-8 by electrostatic interaction to obtain a novel Anderson-Evans ...polyoxometalate-based metal-organic framework composite, TeW6 @ZIF-8. FT-IR, Raman, XRD, TG, DSC, SEM, and TEM were used to characterize the composite. It was proved that the Anderson-Evans type polyoxometalate group TeW6 was successfully hybridized with metal-organic framework ZIF-8, and the composite possesses good stability. Based on the potential interaction between TeW6 and proteins and the coordination between imidazole groups in ZIF-8 and proteins with a porphyrin ring structure, the adsorption selectivity towards different proteins on the TeW6 @ZIF-8 composite was studied in this work. The experiment results showed that the TeW6 @ZIF-8 composite was selectively adsorbed to cytochrome C. At pH 11.0, the adsorption efficiency of 94.01% was obtained for processing 1.0 mL 100 μg mL-1 cytochrome C with 3.0 mg TeW6 @ZIF-8 composite. The adsorption behavior of cytochrome C fits well with the Langmuir adsorption model, corresponding to a theoretical adsorption capacity of 232.56 mg g-1. The retained cytochrome C could be readily recovered by 1% SDS (m/m), giving rise to a recovery of 65.6%. Circular dichroism spectra indicate no conformational change for cytochrome C after the adsorption and desorption processes, demonstrating the favorable biocompatibility of TeW6 @ZIF-8 composite. In applying practical samples, SDS-PAGE results showed that cytochrome C was successfully isolated and purified by TeW6 @ZIF-8 composite from porcine heart protein extract, which is further identified with LC-MS/MS. Thus, a new strategy for separating and purifying cytochrome C from the porcine heart using TeW6 @ZIF-8 composite as an adsorbent was established.
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•Anderson-Evans polyoxometalate-based metal-organic framework composite TeW6 @ZIF-8 forms regular decahedron particles.•Oxygen atom the imidazole group in TeW6 @ZIF-8 depend on the selective adsorption of cytochrome C.•Porphyrin ring of cytochrome C increases the adsorption efficiency under full exposure.•Protein adsorption strategy broadens the biological application of POM/MOF composite.
The biotoxicity of perfluorooctane sulfonate (PFOS) has been a concern. However, the effects of PFOS on Tetrahymena thermophila, a unicellular model organism, remain unclear. This study aimed to ...investigate the toxicity and detoxification mechanism of PFOS in this protozoan. PFOS did not show prominent toxic effects on T. thermophila. Cell viability of T. thermophila can be concentration-dependently increased by PFOS. PFOS also increased the stability of cell membranes and the activity of lysosomes. However, PFOS inhibited efflux transporter activities. Most of the PFOS amount remained in the culture medium during the culture periods. Only a low amount of PFOS was absorbed by cells, where PFOS molecules were mainly combined with membrane proteins. The expressions of four membrane protein genes involved in transporting xenobiotics were analyzed by real time-PCR. The gene abcg25 was significantly up-regulated. The growth of abcg25 gene knockout protozoans under PFOS treatment was slightly inhibited. However, the amount of PFOS adsorbed by the knockout protozoans showed no significant difference from the Wild-type protozoans. We concluded that the ABCG25 protein might play a key role in preventing PFOS from entering the cell or being exported from the cells to protect T. thermophila against PFOS. However, ABCG25 was not the only membrane protein able to bind with PFOS.
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•Adsorbed PFOS in Tetrahymena thermophila mainly combined with membrane proteins.•Gene abcg25 was upregulated under PFOS exposure.•Growth of abcg25 knockout protozoa (abcg25 KO) was inhibited under PFOS exposure.•No difference was found between abcg25 KO and normal cells on adsorbed PFOS amount.•ABCG25 was vital, but not the only protein in preventing PFOS from entering cells.
Quantitative real-time PCR (qPCR) is a popular and powerful tool used to understand the molecular mechanisms of flower development. However, the accuracy of this approach depends on the stability of ...reference genes. The capitulum of chrysanthemums is very special, which is consisting of ray florets and disc florets. There are obvious differences between the two types of florets in symmetry, gender, histological structure, and function. Furthermore, the ray florets have various shapes. The objective of present study was to identify the stable reference genes in Chrysanthemum morifolium and Chrysanthemum lavandulifolium during the process of flower development. In this study, nine candidate reference genes were selected and evaluated for their expression stability acrosssamples during the process of flower development, and their stability was validated by four different algorithms (Bestkeeper, NormFinder, GeNorm, and Ref-finder). SAND (SAND family protein) was found to be the most stably expressed gene in all samples or different tissues during the process of C. lavandulifolium development. Both SAND and PGK (phosphoglycerate kinase) performed most stable in Chinese large-flowered chrysanthemum cultivars, and PGK was the best in potted chrysanthemums. There were differences in best reference genes among varieties as the genetic background of them were complex. These studies provide guidance for selecting reference genes for analyzing the expression pattern of floral development genes in chrysanthemums.
Thermoelectric materials are widely used in space, solar energy, refrigeration, flexible materials and so on, because they can directly convert electric energy and heat energy into each other. In ...this paper, the polycrystalline ceramic materials Bi2Sr2Co2Oy (abbreviated as BSCO) were prepared by the conventional solid-phase reaction sintering method, and their thermoelectric properties were optimized under the dual action of cationic Pb2+ substitution and nano-SiC dispersion. The change of Seebeck coefficients after Pb doping is different from that in theory, which does not accord with the coupling trend of the decrease of resistivity with the increase of Seebeck coefficients. This is because Pb doping opens a pseudogap in BSCO system, which leads to the increase of the Seebeck coefficient. Thus the electrical transportation properties of the materials are improved. Nano-SiC dispersion can increase phonon scattering, thus improve the thermal transport properties of the materials. Under the condition of 973 K and q = 0.025, the power factor of Bi1.6Pb0.4Sr2Co2Oy + q wt% SiC (q = 0, 0.025, 0.05, 0.1 and 0.15) system reaches 307 × 10−6 Wm−1K−2, and the dimensionless thermoelectric figure of merit (ZT) value reaches 0.48, which is the maximum in the previously reported BSCO polycrystalline ceramics.
•High electrical conductivity and low thermal conductivity are obtained simultaneously by Pb-doping and nano-SiC dispersion.•A high ZT value of 0.48 is achieved in Bi1.6Pb0.4Sr2Co2Oy + 0.25 wt% SiC at 973 K.•Seebeck coefficients increase because Pb doping opens a pseudogap in BSCO system.
The semantic segmentation of multi-temporal remote sensing images to construct wetland land surface coverage is the basis for the perception and dynamic modeling of geographic scenes. However, the ...segmentation of Spartina alterniflora (S.alterniflora) in remote sensing images on wetlands faces the problems such as low level for cooperative interpretation in multi-temporal images and high fragmentation in the distribution of S.alterniflora. To solve the issues, a multiple attention network (MARNet) based on transfer learning is proposed. The method is designed with a plug-and-play attention module to enhance the learning of vegetation features and improve the network's ability to focus on small areas of S.alterniflora. At the same time, MARNet designs the transfer learning architecture from both inter-domain alignment and intra-domain adaptation perspectives,aligning the statistical distribution by using the maximum mean difference (MMD) between the source and target domains, and entropy minimization within the domain of the target domain to enhance the high confidence prediction of this domain. In addition, since the samples have a serious imbalance problem, redundant cutting and splicing steps are employed for the prediction results to prevent the poor edge prediction of some image blocks. Experimental results on three cross-year RSIs datasets demonstrate that the proposed MARNet performs significantly better than other networks and is able to extract S.alterniflora in wetlands more accurately.
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