Cell type-specific cytonuclear coevolution in three allopolyploid plant species.

Cytonuclear disruption may accompany allopolyploid evolution as a consequence of the merger of different nuclear genomes in a cellular environment having only one set of progenitor organellar genomes. One path to reconcile potential cytonuclear mismatch is biased expression for maternal gene duplicates (homoeologs) encoding proteins that target to plastids and/or mitochondria. Assessment of this transcriptional form of cytonuclear coevolution at the level of individual cells or cell types remains unexplored. Using single-cell (sc-) and single-nucleus (sn-) RNAseq data from eight tissues in three allopolyploid species, we characterized cell type-specific variations of cytonuclear coevolutionary homoeologous expression and demonstrated the temporal dynamics of expression patterns across development stages during cotton fiber development. Our results provide unique insights into transcriptional cytonuclear coevolution in plant allopolyploids at the single-cell level.

Theoretical Prediction and Experimental Verification of IrOx Supported on Titanium Nitride for Acidic Oxygen Evolution Reaction.

Reducing iridium (Ir) catalyst loading for acidic oxygen evolution reaction (OER) is a critical strategy for large-scale hydrogen production via proton exchange membrane (PEM) water electrolysis. However, simultaneously achieving high activity, long-term stability, and reduced material cost remains challenging. To address this challenge, we develop a framework by combining density functional theory (DFT) prediction using model surfaces and proof-of-concept experimental verification using thin films and nanoparticles. DFT results predict that oxidized Ir monolayers over titanium nitride (IrOx/TiN) should display higher OER activity than IrOx while reducing Ir loading. This prediction is verified by depositing Ir monolayers over TiN thin films via physical vapor deposition. The promising thin film results are then extended to commercially viable powder IrOx/TiN catalysts, which demonstrate a lower overpotential and higher mass activity than commercial IrO2 and long-term stability of 250 h to maintain a current density of 10 mA cm-2. The superior OER performance of IrOx/TiN is further confirmed using a proton exchange membrane water electrolyzer (PEMWE), which shows a lower cell voltage than commercial IrO2 to achieve a current density of 1 A cm-2. Both DFT and in situ X-ray absorption spectroscopy reveal that the high OER performance of IrOx/TiN strongly depends on the IrOx-TiN interaction via direct Ir-Ti bonding. This study highlights the importance of close interaction between theoretical prediction based on mechanistic understanding and experimental verification based on thin film model catalysts to facilitate the development of more practical powder IrOx/TiN catalysts with high activity and stability for acidic OER.

Multiple Metal-Nitrogen Bonds Synergistically Boosting the Activity and Durability of High-Entropy Alloy Electrocatalysts.

The development of Pt-based catalysts for use in fuel cells that meet performance targets of high activity, maximized stability, and low cost remains a huge challenge. Herein, we report a nitrogen (N)-doped high-entropy alloy (HEA) electrocatalyst that consists of a Pt-rich shell and a N-doped PtCoFeNiCu core on a carbon support (denoted as N-Pt/HEA/C). The N-Pt/HEA/C catalyst showed a high mass activity of 1.34 A mgPt-1 at 0.9 V for the oxygen reduction reaction (ORR) in rotating disk electrode (RDE) testing, which substantially outperformed commercial Pt/C and most of the other binary/ternary Pt-based catalysts. The N-Pt/HEA/C catalyst also demonstrated excellent stability in both RDE and membrane electrode assembly (MEA) testing. Using operando X-ray absorption spectroscopy (XAS) measurements and theoretical calculations, we revealed that the enhanced ORR activity of N-Pt/HEA/C originated from the optimized adsorption energy of intermediates, resulting in the tailored electronic structure formed upon N-doping. Furthermore, we showed that the multiple metal-nitrogen bonds formed synergistically improved the corrosion resistance of the 3d transition metals and enhanced the ORR durability.

TGF-ß2-induced alterations of m6A methylation in hTERT RPE-1 cells.

N6-methyladenosine (m6A) is a major type of RNA modification implicated in various pathophysiological processes. Transforming growth factor ß2 (TGF-ß2) induces epithelial-mesenchymal transition (EMT) in retinal pigmental epithelial (RPE) cells and promotes the progression of proliferative vitreoretinopathy (PVR). However, the role of m6A methylation in the EMT of human telomerase reverse transcriptase (hTERT) retinal pigmental epithelium (RPE)-1 cells has not been clarified. Here, we extracted RNA from RPE cells subjected to 0 or 20 ng/mL TGF-ß2 for 72 h and identified differentially methylated genes (DMGs) by m6A-Seq and differentially expressed genes (DEGs) by RNA-Seq. We selected the genes related to EMT by conjoint m6A-Seq/RNA-Seq analysis and verified them by qRT-PCR. We then confirmed the function of m6A methylation in the EMT of RPE cells by knocking down the methyltransferase METTL3 and the m6A reading protein YTHDF1. Sequencing yielded 5814 DMGs and 1607 DEGs. Conjoint analysis selected 467 genes altered at the m6A and RNA levels that are closely associated with the EMT-related TGF-ß, AGE-RAGE, PI3K-Akt, P53, and Wnt signaling pathways. We also identified ten core EMT genes ACTG2, BMP6, CDH2, LOXL2, SNAIL1, SPARC, BMP4, EMP3, FOXM1, and MYC. Their RNA levels were evaluated by qRT-PCR and were consistent with the sequencing results. We observed that METTL3 knockdown enhanced RPE cell migration and significantly upregulated the EMT markers N-cadherin (encoded by CDH2), fibronectin (FN), Snail family transcription repressor (SLUG), and vimentin. However, YTHDF1 knockdown had the opposite effects and decreased both cell migration and the N-cadherin, FN, and SLUG expression levels. The present study clarified TGF-ß2-induced m6A- and RNA-level differences in RPE cells, indicated that m6A methylation might regulate EMT marker expression, and showed that m6A could regulate TGF-ß2-induced EMT.

LncRNA SNHG3 discriminates rheumatoid arthritis from healthy individuals and regulates inflammatory response and oxidative stress via modulating miR-128-3p.

OBJECTIVES: This study evaluated the expression and significance of SNHG3 in Rheumatoid arthritis (RA) aiming to explore a biomarker and regulator for RA. METHODS: The expression of SNHG3 in serum and synovial tissue was compared between RA patients and healthy individuals using PCR. The RA animal models were induced by the porcine type II collagen with Wistar rats and validated by the foot volume and AI score. The human fibroblast-like synoviocytes (H-FLS) were treated with LPS to mimic the injury during RA onset and the cell growth was assessed by CCK8 assay. RESULTS: SNHG3 was significantly downregulated in the serum and synovial tissue of RA patients compared with healthy individuals. Downregulated SNHG3 could discriminate RA patients from healthy individuals with high sensitivity (0.875) and specificity (0.844). Porcine type II collagen induced increasing foot volume and AI scores of rats and SNHG3 was downregulated in RA rats. In LPS-induced H-FLS, SNHG3 negatively regulated miR-128-3p, and the alleviated effect of SNHG3 overexpression on cellular inflammation and oxidative stress was reversed by miR-128-3p upregulation. CONCLUSIONS: Serum SNHG3 was considered a potential diagnostic biomarker for RA from healthy individuals. SNHG3 regulated inflammatory response and oxidative stress via negatively modulating miR-128-3p.

Au/Pt Bimetallic Nanowires with Stepped Pt Sites for Enhanced C-C Cleavage in C2+ Alcohol Electro-oxidation Reactions.

Efficient C-C bond cleavage and oxidation of alcohols to CO2 is the key to developing highly efficient alcohol fuel cells for renewable energy applications. In this work, we report the synthesis of core/shell Au/Pt nanowires (NWs) with stepped Pt clusters deposited along the ultrathin (2.3 nm) stepped Au NWs as an active catalyst to effectively oxidize alcohols to CO2. The catalytic oxidation reaction is dependent on the Au/Pt ratios, and the Au1.0/Pt0.2 NWs have the largest percentage (∼75%) of stepped Au/Pt sites and show the highest activity for ethanol electro-oxidation, reaching an unprecedented 196.9 A/mgPt (32.5 A/mgPt+Au). This NW catalyst is also active in catalyzing the oxidation of other primary alcohols, such as methanol, n-propanol, and ethylene glycol. In situ X-ray absorption spectroscopy and infrared spectroscopy are used to characterize the catalyst structure and to identify key reaction intermediates, providing concrete evidence that the synergy between the low-coordinated Pt sites and the stepped Au NWs is essential to catalyze the alcohol oxidation reaction, which is further supported by DFT calculations that the C-C bond cleavage is indeed enhanced on the undercoordinated Pt-Au surface. Our study provides important evidence that a core/shell structure with stepped core/shell sites is essential to enhance electrochemical oxidation of alcohols and will also be central to understanding electro-oxidation reactions and to the future development of highly efficient direct alcohol fuel cells for renewable energy applications.

Advanced Pt-Based Core-Shell Electrocatalysts for Fuel Cell Cathodes.

ConspectusProton-exchange membrane fuel cells (PEMFCs) are highly efficient energy storage and conversion devices. Thus, the platinum group metal (PGM)-based catalysts which are the dominant choice for the PEMFCs have received extensive interest during the past couple of decades. However, the drawbacks in the existing PGM-based catalysts (i.e., high cost, slow kinetics, poor stability, etc.) still limit their applications in fuel cells. The Pt-based core-shell catalysts potentially alleviate these issues through the low Pt loading with the associated low cost and the high corrosion resistance and further improve the oxygen reduction reaction's (ORR's) activity and stability. This Account focuses on the synthetic strategies, catalytic mechanisms, factors influencing enhanced ORR performance, and applications in PEMFCs for the Pt-based core-shell catalysts. We first highlight the synthetic strategies for Pt-based core-shell catalysts including the galvanic displacement of an underpotentially deposited non-noble metal monolayer, thermal annealing, and dealloying methods, which can be scaled-up to meet the requirements of fuel cell operations. Subsequently, catalytic mechanisms such as the self-healing mechanism in the Pt monolayer on Pd core catalysts, the pinning effect of nitrogen (N) dopants in N-doped PtNi core-shell catalysts, and the ligand effect of the ordered intermetallic structure in L10-Pt/CoPt core-shell catalysts and their synergistic effects in N-doped L10-PtNi catalysts are described in detail. The core-shell structure in the Pt-based catalysts have two main effects for enhanced ORR performance: (i) the interaction between Pt shells and core substrates can tune the electronic state of the surface Pt, thus boosting the ORR activity and stability, and (ii) the outer Pt shell with modest thickness can enhance the oxidation and dissolution resistance of the core, resulting in improved durability. We then review the recent attempts to optimize the ORR performance of the Pt-based core-shell catalysts by considering the shape, composition, surface orientation, and shell thickness. The factors influencing the ORR performance can be grouped into two categories: the effect of the core and the effect of the shell. In the former, PtM core-shell catalysts which use different non-PGM element cores (M) are summarized, and in the latter, Pt-based core-shell catalysts with different shell structures and compositions are described. The modifications of the core and/or shell structure can not only optimize the intermediate-binding energetics on the Pt surface through tuning the strain of the surface Pt, which increases the intrinsic activity and stability, but also offer a significantly decreased catalyst cost. Finally, we discuss the membrane electrode assembly performance of Pt-based core-shell catalysts in fuel cell cathodes and evaluate their potential in real PEMFCs for light-duty and heavy-duty vehicle applications. Even though some challenges to the activity and lifetime in the fuel cells remain, the Pt-based core-shell catalysts are expected to be promising for many practical PEMFC applications.

Pillar[5]arene-Based Fluorescent Supramolecular Polymers Without Conventional Chromophores.

Fluorescent supramolecular polymers have garnered significant attention due to their successful integration of supramolecular polymers and fluorescence, offering vast potential for applications in sensing, imaging, optoelectronics, and photonics. In this study, we present a novel supramolecular polymer based on P5-OH, derived from mono-substituted pillararene macrocycles. Notably, these formed supramolecular polymeric aggregates exhibit a prominent blue emission, representing a rare instance of fluorescent polymers devoid of conventional chromophores. Furthermore, through the modification of alkyl chain ending groups attached to pillar[5]arenes, slight shifts in the emission peak could be observed. This research expands the scope of functional supramolecular polymeric systems utilizing pillararenes, providing valuable insights for the design of innovative luminescent materials and optical devices.

Annexin A2: The diversity of pathological effects in tumorigenesis and immune response.

Annexin A2 (ANXA2) is widely used as a marker in a variety of tumors. By regulating multiple signal pathways, ANXA2 promotes the epithelial-mesenchymal transition, which can cause tumorigenesis and accelerate thymus degeneration. The elevated ANXA2 heterotetramer facilitates the production of plasmin, which participates in pathophysiologic processes such as tumor cell invasion and metastasis, bleeding diseases, angiogenesis, inducing the expression of inflammatory factors. In addition, the ANXA2 on the cell membrane mediates immune response via its interaction with surface proteins of pathogens, C1q, toll-like receptor 2, anti-dsDNA antibodies and immunoglobulins. Nuclear ANXA2 plays a role as part of a primer recognition protein complex that enhances DNA synthesis and cells proliferation by acting on the G1-S phase of the cell. ANXA2 reduction leads to the inhibition of invasion and metastasis in multiple tumor cells, bleeding complications in acute promyelocytic leukemia, retinal angiogenesis, autoimmunity response and tumor drug resistance. In this review, we provide an update on the pathological effects of ANXA2 in both tumorigenesis and the immune response. We highlight ANXA2 as a critical protein in numerous malignancies and the immune host response.

Multiple roles of m6A methylation in epithelial-mesenchymal transition.

Epithelial-mesenchymal transition (EMT) plays an important role in migration and invasion of cancer cell and the development of tissue fibrosis diseases. N6-methyladenosine (m6A) is the most extensive type of RNA methylation and has aroused extensive interest in recent years. However, m6A methylation seems to play different roles in different cancer cells and tissue fibrotic diseases. To determine the function of m6A methylation in EMT, we summarized the molecular mechanism of EMT and recent progress in the regulation of EMT by m6A methylation, suggesting that m6A methylation targets EMT program by affecting the expression of transcription factors, EMT markers, long noncoding RNA and EMT-associated signaling pathways, which provides more possibilities for early diagnosis and treatment.

α-Glucosidase Inhibitory Activity of Fermented Okara Broth Started with the Strain Bacillus amyloliquefaciens SY07.

In this work, a new strain of Bacillus amyloliquefaciens SY07 isolated from a traditional fermented soybean food was reported to possess remarkable α-glucosidase inhibitor-producing ability. Different culture media were applied for the proliferation of B. amyloliquefaciens SY07, and it was found that fermented okara broth presented the highest α-glucosidase inhibitory activity, while Luria-Bertani medium showed a negative effect. The extract from fermented okara broth acted in a dose-dependent manner to inhibit α-glucosidase activity, with an IC50 value of 0.454 mg/mL, and main inhibitors in the fermentation extract presented a reversible, uncompetitive pattern according to Lineweaver-Burk plots. Moreover, 1-deoxynojirimycin, a recognized α-glucosidase inhibitor, was found in the extract. Results indicated that B. amyloliquefaciens SY07 could utilize okara, a by-product from the soy processing industry, to generate α-glucosidase inhibitors effectively, and be regarded as a novel excellent microbial candidate for safe, economical production of potential functional foods or ingredients with hypoglycemic effect.

Optimal design of high-power cascade co-pumping Er/Yb-codoped fiber lasers.

The Yb-ASE problem has been a main obstacle to the power scaling of Er/Yb-codoped fiber lasers (EYDFLs). In this Letter, cascade co-pumping high-power EYDFLs, i.e., EYDFLs with an Yb-band resonant cavity, are proposed and systematically analyzed, for the first time to the best of our knowledge. A high-Q Yb-band cavity is introduced in an EYDFL to lock and recycle the Yb band energy. The oscillation wavelength of the Yb cavity, the reflectivity of the output fiber grating, and the length of the fiber are optimized numerically. Thermal effects are also considered in the study. The simulation results show that compared to ordinary EYDFLs, the introduction of an appropriate Yb cavity can not only effectively suppress the Yb-ASE, increase the output power, and improve the pump conversion efficiency, but can also greatly shorten the optimal gain fiber length. Cascade co-pumping is a promising way to improve the performance of high-power EYDFLs.

Electrochemical sensors based on molecularly imprinted polymers on Fe3O4/graphene modified by gold nanoparticles for highly selective and sensitive detection of trace ractopamine in water.

A novel molecular imprinting polymer (MIP)-based electrochemical senor, consisting of Fe3O4 nanobeads and gold nanoparticles on a reduced graphene oxide (RGO) substrate, was fabricated to detect ractopamine (RAC) in water using the reversible addition fragmentation chain transfer (RAFT) polymerization technique. The Au nanoparticles widely dispersed on RGO can significantly increase the response current for RAC detection in water, which is confirmed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and theoretical calculations. By means of the differential pulse voltammetry technique, the as-prepared MIP-based electrode shows a dynamic linear range of 0.002 to 0.1 µM with a correlation coefficient of 0.992 and a remarkably low detection limit of 0.02 nM (S/N = 3). Additionally, the sensor exhibits high binding affinity and selectivity towards RAC with excellent reproducibility. Our study demonstrates the potential for the proposed electrochemical sensors in monitoring organic pollutants in water.

Numerical investigation of the thermal effect on Yb-cavity-copumped Er/Yb codoped fiber amplifiers.

Thermal effects are critical constraints for developing high-power Er/Yb-codoped fiber amplifiers (EYDFAs), especially those with an auxiliary Yb-band cavity. In this paper, we developed a numerical model to investigate the temperature-dependent effects on EYDFAs with an Yb-band cavity with consideration of thermal-induced cross-section changes. Our results show that the quantum-defect-induced heat affects the performance of the EYDFA, and its effect varies with the resonant wavelength of the Yb-band cavity. There is a finite applicable resonant wavelength range limited by thermal damage. So, it is important to take into account the thermal effect during the design of such EYDFAs in order to optimize their performance and determine the heat dissipation systems.

Method for estimating the Stark splitting of rare-earth ions from the measured cross-section spectra.

A method to estimate the Stark levels of the rare-earth ions doped in a laser medium from the measured emission and absorption cross-sections is proposed. The method is based on the McCumber theory, which can calculate the emission/absorption cross-sections from the given Stark levels. By fitting the calculated emission/absorption spectra to the measured ones through a numerical optimization process, the Stark levels of the RE ions can be determined. As examples, the Stark levels of the laser-emission-related manifolds of Er3+ and Yb3+ ions in a gain fiber and two doped glasses have been determined by the proposed method. The data were then used to analyze the temperature-dependent population of the Stark levels. This method avoids the difficulties in direct measurement of the Stark levels in a cryogenic temperature environment. It is important to the evaluation of the thermal load, distribution, and design of the thermal management system of high-power fiber lasers and amplifiers.

The embodiment of beauty: Evidence from viewing Chinese concrete words and pictographs.

How is beauty embodied? According to the viewpoint of embodied cognition, the aesthetic processing of words or pictographs has roots in their referential archetypes. Four experiments tested whether the beauty of referential archetypes was routinely activated during the explicit and implicit aesthetic evaluations of the font structures of concrete Chinese words and pictographs in congruent or incongruent font colour. Results showed font structures of simplified Chinese words and pictographs were judged to be more beautiful when they referred to beautiful archetypes; and this pattern was reversed when they referred to ugly archetypes. Moreover, judgement was facilitated when font colour was congruent for Chinese words and pictographs referred to beautiful archetypes. For those referred to ugly archetypes, judgement was inhibited in congruent font colour but facilitated in incongruent font colour, suggesting aesthetic perceptions of the font structures of Chinese words and pictographs were derived from their referential natural objects. The spontaneous generation hypothesis of beauty is proposed to account for these findings.

Interpersonal choice: The advantage on the left or on the right?

This study explored whether body specificity unconsciously influenced preferences for certain people. Participants were presented pictures of the heads of 2 persons who were described as having the similar personality, profession and family background. They were instructed to choose 1 in each pair as the preferred date, preferred friend, more charismatic boss or as the better national leader. The results showed body specificity had an influence on the selection preference on first impression. Participants tended to choose the character on their dominant-hand side. This study not only provided the first social psychological evidence for the body-specificity hypothesis, but also first demonstrated a role for body specificity in impression formation and selection preference.

[Identification, cloning and functional verification of U6 promoter from Cryptococcus neoformans].

Objective: To identify and clone the polymerase Ⅲ U6 promoter from Cryptococcus neoformans (CnU6 promoter), and verify if CnU6 promoter can effectively transcribe shRNA and gRNA of CRISPR/Cas9 system. Methods: Combining the C. neoformans genome information published in GenBank database and RNA-seq library data from our laboratory, we obtained the U6 RNA sequence with high transcriptional level by bioinformatics analysis. The putative CnU6 promoter was ligated upstream of shRNA and gRNA by EasyGeno and overlapping PCR respectively. Based on shRNA-mediated target gene silence phenotype by RNAi and gene mutation by gRNA-guided Cas9 nuclease mediated target sites editing by CRISPR/Cas9 system, we could identify if CnU6 promoter could drive the transcription of short RNA. Results: CnU6 promoter could drive the transcribtion of shRNA, which could silence the target gene, and gRNA, which could guide Cas9 nuclease to cut the target site. Conclusion: The CnU6 promoter from C. neoformans was successfully identified and cloned, which could drive the transcription of shRNA and gRNA efficiently.

Effects of CTR4 deletion on virulence and stress response in Cryptococcus neoformans.

Roles of the high-affinity copper transporter Ctr4 in the virulence of Cryptococcus neoformans remain to be fully determined. Here we demonstrate that Ctr4 plays a necessary role in virulence and tolerance to a number of stress conditions. We first observed, with the method of flame atomic absorption spectrometry, that deletion of CTR4 resulted in a significant decrease in intracellular copper level, confirming the role of Ctr4 as a copper transporter in C. neoformans. Furthermore, CTR4 was critical for the yeast to survive at both elevated and low temperatures, as the growth rate of the ctr4Δ mutant at 4 and 37 °C was significantly decreased. The mutant ctr4Δ also exhibited hypersensitivity to osmotic stress imposed by 2 M NaCl or KCl, indicating the possible crosstalk of Ctr4 with the HOG signalling pathway. Moreover, cell wall and plasma membrane integrity appeared to be impaired in the ctr4Δ strain. The virulence of ctr4Δ in two mouse cryptococcosis models was remarkably reduced either via an intranasal or intravenous inoculation. Our work confirms the roles of Ctr4 in virulence and copper homeostasis as well as other additional novel functions.

Clinical significance of long non-coding RNA NORAD in rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disease that may cause joint deformities and seriously affect the normal life of the patients. In order to enable patients to receive timely attention and treatment, this study developed new diagnostic markers by exploring the expression and molecular mechanism of the long non-coding RNA NORAD (NORAD) in RA. METHODS: Participants including 77 RA patients and 52 healthy persons were enrolled, and the corresponding clinical data and serum samples were obtained. The NORAD and miR-204-5p expression were detected by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). The content of inflammatory cytokines (IL-6, TNF-α) were determined through enzyme-linked immunosorbent assay (ELISA). Luciferase activity reporter assay demonstrated the association between NORAD and miR-204-5p. In addition, receiver operating characteristic (ROC) curve was used to evaluate the diagnostic efficacy of NORAD, and Pearson's correlation analysis was applied for the correlation analysis. RESULTS: NORAD was enriched in RA serum with high diagnostic value. Simultaneously, IL-6 and TNF-α levels were also upregulated (P < 0.001). The C-reactive protein (CRP), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR) and anti-cyclic citrullinated peptide antibody (Anti-CCP) levels in RA patients were generally elevated (P < 0.001). NORAD was positively correlated with the levels of clinical indicators and inflammatory factors (P < 0.0001). Mechanistically, NORAD may affect the progression of RA by targeting and negatively regulating miR-204-5p. CONCLUSIONS: There is a correlation between NORAD and the processes of RA, and NORAD has the potential to predict and diagnose the occurrence of RA.