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Te-based materials with excellent electrical conductivity and ultra-high volume specific capacity have attracted much attention for the cost-efficient aqueous Zn batteries. However, the construction of functional structures with mild volume expansion and suppressed shuttle effects, enabling an expanded lifespan, is still a challenge for conversion-type materials. Herein, the carbon-coated zinc telluride nanowires (ZnTe@C NWs) are rationally designed as a high-performance cathode material for aqueous Zn batteries. The carbon-coated1D nanostructure could not only provide optimized transmission path for electrons and ions, but also help to maintain structure integrity upon volume variation and suppress intermediates dissolution, endowing the ZnTe@C NWs with improved cycling stability and reaction kinetics. Consequently, a reversible six-electron reaction mechanism of ZnTe@C NWs based on Te2- /Te4+ conversion with excellent output capacity (586 mAh g-1 at 0.1 A g-1 ) and lifespan (>250 mAh g-1 retained for 400 cycles at 1 A g-1 ) is eventually achieved.
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MOTIVATION: The computational prediction of regulatory function associated with a genomic sequence is of utter importance in -omics study, which facilitates our understanding of the underlying mechanisms underpinning the vast gene regulatory network. Prominent examples in this area include the binding prediction of transcription factors in DNA regulatory regions, and predicting RNA-protein interaction in the context of post-transcriptional gene expression. However, existing computational methods have suffered from high false-positive rates and have seldom used any evolutionary information, despite the vast amount of available orthologous data across multitudes of extant and ancestral genomes, which readily present an opportunity to improve the accuracy of existing computational methods. RESULTS: In this study, we present a novel probabilistic approach called PhyloPGM that leverages previously trained TFBS or RNA-RBP binding predictors by aggregating their predictions from various orthologous regions, in order to boost the overall prediction accuracy on human sequences. Throughout our experiments, PhyloPGM has shown significant improvement over baselines such as the sequence-based RNA-RBP binding predictor RNATracker and the sequence-based TFBS predictor that is known as FactorNet. PhyloPGM is simple in principle, easy to implement and yet, yields impressive results. AVAILABILITY AND IMPLEMENTATION: The PhyloPGM package is available at https://github.com/BlanchetteLab/PhyloPGM. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Genômica , Sequências Reguladoras de Ácido Nucleico , DNA , Genômica/métodos , Humanos , RNA , Análise de Sequência de DNA/métodosRESUMO
The electrochemical reactions for the storage of Zn2+ while embracing more electron transfer is a foundation of the future high-energy aqueous zinc batteries. Herein, we report a six-electron transfer electrochemistry of nano-sized TeO2 /C (n-TeO2 /C) cathode by facilitating the reversible conversion of TeO2 âTe and TeâZnTe. Benefitting from the integrated conductive nanostructure and the proton-rich environment in providing optimized electrochemical kinetics (facilitated Zn2+ uptake and high electronic conductivity) and feasible thermodynamic process (low Gibbs free energy change), the as-prepared n-TeO2 /C with stable cycling performance exhibits a superior reversible capacity of over 800â mAh g-1 at 0.1â A g-1 . A precise understanding of the reaction mechanism via ex situ and in situ characterizations presents that the reversible six-electron transfer reaction is proton-dependent, and a proton generating and consuming mechanism of three-phase conversion n-TeO2 /C in the weakly acidic electrolyte is thoroughly revealed.
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The performance of single-atom catalysts strongly depends on their particular coordination environments in the near-surface region. Herein, we discover that engineering extra Pt single atoms in the subsurface (Ptsubsurf) can significantly enhance the catalytic efficiency of surface Pt single atoms toward the oxygen reduction reaction (ORR). We experimentally and theoretically investigated the effects of the Ptsubsurf single atoms implanted in different positions of the subsurface of Co particles. The local environments and catalytic properties of surface Pt1 are highly tunable via Ptsubsurf doping. Specifically, the obtained Pt1@Co/NC catalyst displays a remarkable performance for ORR, achieving mass activity of 4.2 mA µgPt-1 (28 times higher than that of commercial Pt/C) at 0.9 V versus reversible hydrogen electrode (RHE) in 0.1 M HClO4 solution with high stability over 30000 cycles.
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Aqueous Zn-S battery with high energy density represents a promising large-scale energy storage technology, but its application is severely hindered by the poor reversibility of both S cathode and Zn anode. Herein, we develop a "cocktail optimized" electrolyte containing tetraglyme (G4) and water as co-solvents and I2 as additive. The G4-I2 synergy could activate efficient polar I3 - /I- catalyst couple and shield the cathode from water, thus facilitating the conversion kinetics of S and suppressing the interfacial side reactions. Simultaneously, it could stabilize Zn anode by forming an organic-inorganic interphase upon cycling. With boosted electrodes reversibility, the Zn-S cell delivers a high capacity of 775â mAh g-1 at 2â A g-1 , and retains over 70 % capacity after 600 cycles at 4â A g-1 . The advances can also be readily generalized to other ethers/water hybrid electrolytes, showing the universality of the "cocktail optimized" electrolyte design strategy.
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MOTIVATION: RNA-protein interactions are key effectors of post-transcriptional regulation. Significant experimental and bioinformatics efforts have been expended on characterizing protein binding mechanisms on the molecular level, and on highlighting the sequence and structural traits of RNA that impact the binding specificity for different proteins. Yet our ability to predict these interactions in silico remains relatively poor. RESULTS: In this study, we introduce RPI-Net, a graph neural network approach for RNA-protein interaction prediction. RPI-Net learns and exploits a graph representation of RNA molecules, yielding significant performance gains over existing state-of-the-art approaches. We also introduce an approach to rectify an important type of sequence bias caused by the RNase T1 enzyme used in many CLIP-Seq experiments, and we show that correcting this bias is essential in order to learn meaningful predictors and properly evaluate their accuracy. Finally, we provide new approaches to interpret the trained models and extract simple, biologically interpretable representations of the learned sequence and structural motifs. AVAILABILITY AND IMPLEMENTATION: Source code can be accessed at https://www.github.com/HarveyYan/RNAonGraph. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Redes Neurais de Computação , RNA , Ligação Proteica , Estrutura Secundária de Proteína , RNA/metabolismo , SoftwareRESUMO
Manganese-based Prussian Blue, Na2-δ Mn[Fe(CN)6 ] (MnPB), is a good candidate for sodium-ion battery cathode materials due to its high capacity. However, it suffers from severe capacity decay during battery cycling due to the destabilizing Jahn-Teller distortions it undergoes as Mn2+ is oxidized to Mn3+ . Herein, the structure is stabilized by a thin epitaxial surface layer of nickel-based Prussian Blue (Na2-δ Ni[Fe(CN)6 ]). The one-pot synthesis relies on a chelating agent with an unequal affinity for Mn2+ and Ni2+ ions, which prevents Ni2+ from reacting until the Mn2+ is consumed. This is a new and simpler synthesis of core-shell materials, which usually needs several steps. The material has an electrochemical capacity of 93â mA h g-1 , of which it retains 96 % after 500 charge-discharge cycles (vs. 37 % for MnPB). Its rate capability is also remarkable: at 4â A g-1 (ca. 55â C) it can reversibly store 70â mA h g-1 , which is also reflected in its diffusion coefficient of ca. 10-8 â cm2 s-1 . The epitaxial outer layer appears to exert an anisotropic strain on the inner layer, preventing the Jahn-Teller distortions it normally undergoes during de-sodiation.
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MOTIVATION: Messenger RNA subcellular localization mechanisms play a crucial role in post-transcriptional gene regulation. This trafficking is mediated by trans-acting RNA-binding proteins interacting with cis-regulatory elements called zipcodes. While new sequencing-based technologies allow the high-throughput identification of RNAs localized to specific subcellular compartments, the precise mechanisms at play, and their dependency on specific sequence elements, remain poorly understood. RESULTS: We introduce RNATracker, a novel deep neural network built to predict, from their sequence alone, the distributions of mRNA transcripts over a predefined set of subcellular compartments. RNATracker integrates several state-of-the-art deep learning techniques (e.g. CNN, LSTM and attention layers) and can make use of both sequence and secondary structure information. We report on a variety of evaluations showing RNATracker's strong predictive power, which is significantly superior to a variety of baseline predictors. Despite its complexity, several aspects of the model can be isolated to yield valuable, testable mechanistic hypotheses, and to locate candidate zipcode sequences within transcripts. AVAILABILITY AND IMPLEMENTATION: Code and data can be accessed at https://www.github.com/HarveyYan/RNATracker. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Redes Neurais de Computação , Aprendizado Profundo , Estrutura Secundária de Proteína , RNA MensageiroRESUMO
Herein, we report a comprehensive strategy to synthesize a full range of single-atom metals on carbon matrix, including V, Mn, Fe, Co, Ni, Cu, Ge, Mo, Ru, Rh, Pd, Ag, In, Sn, W, Ir, Pt, Pb, and Bi. The extensive applications of various SACs are manifested via their ability to electro-catalyze typical hydrogen evolution reactions (HER) and conversion reactions in novel room-temperature sodium sulfur batteries (RT-Na-S). The enhanced performances for these electrochemical reactions arisen from the ability of different single active atoms on local structures to tune their electronic configuration. Significantly, the electrocatalytic behaviors of diverse SACs, assisted by density functional theory calculations, are systematically revealed by inâ situ synchrotron X-ray diffraction and inâ situ transmission electronic microscopy, providing a strategic library for the general synthesis and extensive applications of SACs in energy conversion and storage.
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Two-dimensional (2D) superlattices offer promising technological opportunities in tuning the intercalation chemistry of metal ions. Now, well-ordered 2D superlattices of monolayer titania and carbon with tunable interlayer-spacing are synthesized by a molecularly mediated thermally induced approach. The 2D superlattices are vertically encapsulated in hollow carbon nanospheres, which are embedded with TiO2 quantum dots, forming a 0D-2D-3D multi-dimensional architecture. The multi-dimensional architecture with the 2D superlattices encapsulated inside exhibits a near zero-strain characteristic and enriched electrochemical reactivity, achieving a highly efficient Na+ storage performance with exceptional rate capability and superior long-term cyclability.
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Low-cost layered oxides free of Ni and Co are considered to be the most promising cathode materials for future sodium-ion batteries. Biphasic Na0.78 Cu0.27 Zn0.06 Mn0.67 O2 obtained via superficial atomic-scale P3 intergrowth with P2 phase induced by Zn doping, consisting of inexpensive transition metals, is a promising cathode for sodium-ion batteries. The P3 phase as a covering layer in this composite shows not only in excellent electrochemical performance but also its tolerance to moisture. The results indicate that partial Zn substitutes can effectively control biphase formation for improving the structural/electrochemical stability as well as the ionic diffusion coefficient. Based on inâ situ synchrotron X-ray diffraction coupled with electron-energy-loss spectroscopy, a possible Cu2+/3+ redox reaction mechanism has now been revealed.
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Both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) are crucial to water splitting, but require alternative active sites. Now, a general π-electron-assisted strategy to anchor single-atom sites (M=Ir, Pt, Ru, Pd, Fe, Ni) on a heterogeneous support is reported. The M atoms can simultaneously anchor on two distinct domains of the hybrid support, four-fold N/C atoms (M@NC), and centers of Co octahedra (M@Co), which are expected to serve as bifunctional electrocatalysts towards the HER and the OER. The Ir catalyst exhibits the best water-splitting performance, showing a low applied potential of 1.603â V to achieve 10â mA cm-2 in 1.0 m KOH solution with cycling over 5â h. DFT calculations indicate that the Ir@Co (Ir) sites can accelerate the OER, while the Ir@NC3 sites are responsible for the enhanced HER, clarifying the unprecedented performance of this bifunctional catalyst towards full water splitting.
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Aqueous zinc ion batteries (AZIBs) are promising candidates for next-generation energy storage systems due to their low cost, high safety, and environmental friendliness. As the critical component, Zn metal with high theoretical capacity (5855 mAh cm-3), low redox potential (-0.763 V vs standard hydrogen electrode), and low cost has been widely applied in AZIBs. However, the low Zn utilization rate (ZUR) of Zn metal anode caused by the dendrite growth, hydrogen evolution, corrosion, and passivation require excess Zn installation in current AZIBs, thus leading to increased unnecessary battery weight and decreased energy density. Herein, approaches to the historical progress toward high ZUR AZIBs through the perspective of electrolyte optimization, anode protection, and substrate construction are comprehensively summarized, and an in-depth understanding of ZUR is highlighted. Specifically, the main challenges and failure mechanisms of Zn anode are analyzed. Then, the persisting issues and promising solutions in the reaction interface, aqueous electrolyte, and Zn anode are emphasized. Finally, the design of 100% ZUR AZIBs free of Zn metal is presented in detail. This review aims to provide a better understanding and fundamental guidelines on the high ZUR AZIBs design, which can shed light on research directions for realizing high energy density AZIBs.
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Due to their unique afterglow ability, long-wavelength-light rechargeable persistent luminescence (PersL) nanoparticles (PLNPs) have been emerging as an important category of imaging probes. Among them, ZnGa2O4:0.6% Cr3+ (ZGC) PLNPs have gained widespread recognition due to the ease of synthesis and uniform morphology. Unfortunately, the limited absorption arising from the low molar extinction coefficient of Cr3+ results in relatively low afterglow intensity and rapid decay after long-wavelength LED light irradiation. Herein, we discovered a strategy that boosting dye-sensitization performance was able to effectively amplify the PersL signal under white LED light. Specifically, Dil served as a highly efficient sensitizer for Cr3+, promoting the absorption of the excitation light. By adjusting the Pr dopant concentrations, ZGCP0.5 PLNPs with optimal trap densities were obtained, which showed the highest PersL intensity and dye-sensitized performance. Strikingly, ZGCP0.5-Dil PLNPs exhibited a 24.3-fold enhancement in intensity and a 2-fold prolongation of decay time over bare ZGC PLNPs through the synergy effect of optimal electron traps and dye sensitization. Photostable ZGCP0.5-Dil PLNPs enabled imaging of the HepG2 tumor and effectively guided tumor surgical resection verified by the H&E staining analysis. This strategy could be a significant reference in other dye-sensitization PLNPs to enhance longer-wavelength rechargeable PersL.
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Surgical resection remains the main treatment for malignant tumors. Image-guided surgery aims to remove tumor tissue completely while preserving normal tissue, thereby reducing tumor recurrence rates and injury. However, challenges like tissue autofluorescence, limited probe penetration and low contrast restrict its use. Near-infrared (NIR) persistent luminescent nanoparticles (PLNPs) provide a solution by emitting persistent luminescence (PersL) even after excitation ceases, thus circumventing autofluorescence and enabling deep tumor imaging. In this study, we prepared nano-sized (140 nm hydrodynamic size) Cr3+ doped zinc gallogermanate (ZGC) using a removable template method and modified it with folate acid to obtain ZGC-FA, which exhibits NIR (695 nm) PersL with a signal-to-noise ratio of 23.9 in vivo. We utilized a colon cancer model that selectively expressed luciferase for the first time to validate the guiding efficacy of ZGC-FA in precision surgical resection. Post-intraperitoneal injection at 50 minutes, the PersL closely matched the tumor boundaries, achieving an overlap rate of approximately 98%. Complete tumor resection was achieved under PersL guidance, with only 2.3% of healthy tissue removed. This research underscores the potential of ZGC-FA in the field of surgical oncology. The precision of the ZGC-FA guided surgical approach holds promise to enhance surgical outcomes and facilitate postoperative recovery in patients.
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Linearly interlinked single atoms offer unprecedented physiochemical properties, but their synthesis for practical applications still poses significant challenges. Herein, linearly interlinked iron single-atom catalysts that are loaded onto interconnected carbon channels as cathodic sulfur hosts for room-temperature sodium-sulfur batteries are presented. The interlinked iron single-atom exhibits unique metallic iron bonds that facilitate the transfer of electrons to the sulfur cathode, thereby accelerating the reaction kinetics. Additionally, the columnated and interlinked carbon channels ensure rapid Na+ diffusion kinetics to support high-rate battery reactions. By combining the iron atomic chains and the topological carbon channels, the resulting sulfur cathodes demonstrate effective high-rate conversion performance while maintaining excellent stability. Remarkably, even after 5000 cycles at a current density of 10 A g-1, the Na-S battery retains a capacity of 325 mAh g-1. This work can open a new avenue in the design of catalysts and carbon ionic channels, paving the way to achieve sustainable and high-performance energy devices.
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The enrichment rate of drugs in tumors seriously affects the effect of tumor treatment. Tumor-associated macrophages (TAMs) could penetrate deeply into the tumor and accumulate in hypoxic areas. Therefore, using TAMs to deliver drugs can effectively increase the enrichment rate. However, as immune cell, macrophages will clear the internal drugs and their antitumor activity. Mycobacterium tuberculosis (M. tuberculosis) can inhibit the decomposition ability of TAMs and stay stable in macrophages. Herein, we prepared a Bacillus-mimic liposome by embedding the fragments of M. tuberculosis into the liposome. In vitro experiments showed that it can stay stable in TAMs for at least 29 h without decomposing. Then, TAMs would burst as they gobble up materials and cannot digest them. Thus, the prepared liposome could "domesticate" TAMs and kill macrophages after they are used up, further destroy the tumor microenvironment, and finally kill the tumor. Cytotoxicity experiments confirmed that it has a certain killing effect on macrophages, tumor cells, and normal cells. In vivo tumor suppression experiments confirmed that it has the effect of inhibiting tumor growth.
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Bacillus , Neoplasias , Tuberculose , Humanos , Lipossomos/uso terapêutico , Macrófagos Associados a Tumor/patologia , Neoplasias/tratamento farmacológico , Microambiente TumoralRESUMO
NIR persistent luminescence nanoparticles (PLNPs) are appealing for bio-imaging because of the properties of extremely low autofluorescence interference and deep tissue penetrating ability. However, current preparation methods can hardly simultaneously endow PLNPs with nano-scale size, long persistent luminescence (PersL) life, and high luminescence intensity, which can hardly meet the requirements of bio-imaging. Herein, we report a new synthetic route to nano-sized chromium-doped zinc gallate (ZGC) via a removable MOF template, i.e., one-pot hydrothermal synthesis of an intermediate followed by its calcination at 1100 °C in air. By exploiting the regulatory effect of the intermediate on Zn and Ga, the depth of traps in 170 nm-sized ZGC nanoparticles was enhanced to above 0.8 eV, and the PersL duration to more than 24 h, with an average lifetime of up to 216 s. An in vivo experiment shows that tumors can be accurately delineated for more than 3 hours. This strategy largely resolves the conflict between the particle size and PersL properties of PLNPs, and expands the application of PLNPs in bio-imaging.
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Nanopartículas , Neoplasias , Humanos , Luminescência , Diagnóstico por Imagem , CromoRESUMO
Noble metal compositing is a promising method to enhance radiance intensity of persistent luminescent (PersL) nanoparticles (NPs) via surface plasmon resonance (SPR) for better tumor imaging, but it rarely unites with the pH-response strategy due to the challenge of realizing rigorous pH-responsive spatial distance control as a "button switch" of SPR. Here, ZnGa2O4:Cr3+ (ZGC) NPs as "pomegranate seeds" are cladded with sodium alginate to form nanoclusters (ZGC-SA), subsequently coated with carboxyl-rich polymers to acquire "pomegranate rind" (ZSPB) and finally decorated with 10 nm gold NPs (AuNPs) on the surface to obtain nanopomegranate structure (ZSPB@AuNPs). Though without deliberate distance control, there are plenty of "seeds" inside ZSPB@AuNPs fortunately at appropriate positions, which could be plasmon-enhanced by AuNPs. Furthermore, triggered by carboxyl protonation in subacid tumor, ZSPB@AuNPs aggregate and subsequently facilitate such plasmon enhancement effect, resulting in 4.4-fold PersL promotion at pH 5.5 (tumor microenvironment, TME) over pH 7.4 and in a maximum "tumor to normal tissue ratio" of PersL imaging signals of 125.9. Under surgical navigation of ZSPB@AuNPs, intramuscular tumors of mice could be resected without residue signals left. This nanopomegranate achieves TME pH-responsive plasmon-enhanced PersL for the first time and broadens the way for designing plasmon-enhanced PersL nanosystems.
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Nanopartículas Metálicas , Neoplasias , Animais , Camundongos , Nanopartículas Metálicas/química , Ouro/química , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Ressonância de Plasmônio de Superfície , Concentração de Íons de Hidrogênio , Microambiente TumoralRESUMO
Low accumulation and penetration of nanomedicines in tumor severely reduce therapeutic efficacy. Herein, a pH-responsive gold nanoassembly is designed to overcome these problems. Polyethylene glycol linked raltitrexed (RTX, target ligand and chemotherapy drug) and two tertiary amine molecules (1-(2-aminoethyl) pyrrolidine and N, N-dibutylethylenediamine) are modified on the surface of the 6-nm gold nanoparticles by lipoic acid to form gold nanoassembly defined as Au-NNP(RTX). The Au-NNP (RTX) nanoassembly could remain at about 160 nm at the blood circulation (pH 7.4), while split into 6-nm gold nanoparticles due to tertiary amine protonation at tumor extracellular pH (pH 6.8). This pH-responsive disassembly behavior endows Au-NNP(RTX) better tumor tissue permeability through the better diffusion brought by the size reduction. Meanwhile, after disassembly, more RTXs on the surface of gold nanoparticles are exposed from the shielded state of assembly along with 2.25-fold augment of cellular uptake capability. Most importantly, the results show that Au-NNP(RTX) possesses of high tumor accumulation and effective tumor penetration, thereby enhancing the tumor chemo-radiotherapy efficiency.