Effect of heat stress on blood biochemistry and energy metabolite of the Dazu black goats.

The objective of this study was to determine the effects of heat stress (HS) on physiological, blood biochemical, and energy metabolism in Dazu black goats. Six wether adult Dazu black goats were subjected to 3 experimental periods: high HS (group H, temperature-humidity index [THI] > 88) for 15 d, moderate HS (group M, THI was 79-88) for 15 d, and no HS (group L, THI < 72) for 15 d. Rectal temperature (RT) and respiratory rate (RR) were determined on d 7 and 15 of each period, and blood samples were collected on d 15 of each period. All goats received glucose (GLU) tolerance test (GTT) and insulin (INS) tolerance test on d 7 and d 10 of each period. The results showed that HS decreased dry matter intake (DMI) and INS concentration (p < 0.05), and increased RT, RR, non-esterified fatty acid (NEFA), cortisol (COR), and total protein (TP) concentrations (p < 0.05). Compared to group L, the urea nitrogen (BUN) concentration increased and GLU concentration decreased in group H (p < 0.05). During the GTT, the area under the curve (AUC) of GLU concentrations increased by 12.26% (p > 0.05) and 40.78% (p < 0.05), and AUC of INS concentrations decreased by 26.04 and 14.41% (p < 0.05) in groups H and M compared to group L, respectively. The INS concentrations were not significant among the three groups (p > 0.05) during the ITT. A total of 60 differentially expressed metabolites were identified in response to groups H and M. In HS, changes in metabolites related to carbohydrate metabolism and glycolysis were identified (p < 0.05). The metabolites related to fatty acid ß-oxidation accumulated, glycogenic and ketogenic amino acids were significantly increased, while glycerophospholipid metabolites were decreased in HS (p < 0.05). HS significantly increased 1-methylhistidine, creatinine, betaine, taurine, taurolithocholic acid, inosine, and hypoxanthine, while decreasing vitamin E in blood metabolites (p < 0.05). In summary, HS changed the metabolism of fat, protein, and energy, impaired GLU tolerance, and mainly increased amino acid metabolism to provide energy in Dazu black goats.

Extrachromosomal circular DNA (eccDNA) characteristics in the bile and plasma of advanced perihilar cholangiocarcinoma patients and the construction of an eccDNA-related gene prognosis model.

Extrachromosomal DNAs (eccDNAs) frequently carry amplified oncogenes. This investigation aimed to examine the occurrence and role of eccDNAs in individuals diagnosed with advanced perihilar cholangiocarcinoma (pCCA) who exhibited distinct prognostic outcomes. Five patients with poor survival outcomes and five with better outcomes were selected among patients who received first-line hepatic arterial infusion chemotherapy from June 2021 to June 2022. The extracted eccDNAs were amplified for high-throughput sequencing. Genes associated with the differentially expressed eccDNAs were analyzed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. The differentially expressed bile eccDNA-related genes were used to construct a prognostic model. Across all 10 patients, a total of 19,024 and 3,048 eccDNAs were identified in bile and plasma, respectively. The concentration of eccDNA detected in the bile was 9-fold higher than that in plasma. The chromosome distribution of the eccDNAs were similar between bile and matched plasma. GO and KEGG pathway analyses showed enrichment in the mitogen-activated protein kinase (MAPK) and Wnt/ß-catenin pathways in patients with poor survival outcomes. According to the prognostic model constructed by eccDNA-related genes, the high-risk group of cholangiocarcinoma patients displayed significantly shorter overall survival (p < 0.001). Moreover, the degree of infiltration of immunosuppressive cells was higher in patients in the high-risk group. In conclusion, EccDNA could be detected in bile and plasma of pCCA patients, with a higher concentration. A prognostic model based on eccDNA-related genes showed the potential to predict the survival and immune microenvironment of patients with cholangiocarcinoma.

Nanoassembly-Mediated Exendin-4 Derivatives to Decrease Renal Retention.

An Exendin-4 analogue that was conjugated with 68Ga exhibited an excellent diagnostic effect on insulinoma in clinical practice. On account of its low molecular weight and short hydration radius, 68Ga-Exendin-4 showed high accumulation in kidney tissues. Nanoparticle-mediated strategies have attracted much attention due to polyvalent properties and the size amplification effect. In this study, Exendin-4 derivatives of radionuclide nanodevices were developed and evaluated. The Exendin-4 derivatives consisting of a ternary block recombinant protein were purified by an inverse transition cycle (ITC) and allowed to self-assemble into a nanodevice under physiological conditions. Our results showed that the nanoassemblies of Exendin-4 derivatives formed homogeneous spherical nanoparticles, exhibited outstanding affinity for insulinoma cells, and could be deposited in insulinoma tissues in vivo. The nanoassembly-mediated Exendin-4 derivatives showed fivefold reduced renal retention and exhibited an outstanding tumor-suppression effect.

Analyzing the Active Site and Predicting the Overall Activity of Alloy Catalysts.

As one of the potential catalysts, disordered solid solution alloys can offer a wealth of catalytic sites. However, accurately evaluating their activity localization structure and overall activity from each individual site remains a formidable challenge. Herein, an approach based on density functional theory and machine learning was used to obtain a large number of sites of the Pt-Ru alloy as the model multisite catalyst for the hydrogen evolution reaction. Subsequently, a series of statistical approaches were employed to unveil the relationship between the geometric structure and overall activity. Based on the radial frequency distribution of metal elements and the distribution of ΔGH, we have identified the surface and subsurface sites occupied by Pt and Ru, respectively, as the most active sites. Particularly, the concept of equivalent site ratio predicts that the overall activity is highest when the Ru content is 20-30%. Furthermore, a series of Pt-Ru alloys were synthesized to validate the proposed theory. This provides crucial insights into understanding the origin of catalytic activity in alloys and thus will better guide the rational development of targeted multisite catalysts.

Anlotinib for Metastatic Progressed Pheochromocytoma and Paraganglioma: A Retrospective Study of Real-World Data.

Introduction: Pheochromocytomas (PCC) and paragangliomas (PGL) (collectively PPGL) are a type of rare hypervascular neuroendocrine tumors that are very challenging to treat. This study aimed to determine the efficacy and safety of the multi-tyrosine kinase inhibitor anlotinib for the treatment of locally advanced or metastatic (LA/M) PPGL. Methods: A total of 37 eligible patients with unresectable or progressive LA/M PPGL were enrolled. Of them, 27 patients received anlotinib alone (n = 19) or in combination (n = 8) with radionuclide therapies, including peptide receptor radionuclide therapy (PRRT) and iodine 131 meta-iodobenzylguanidine (131I-MIBG). The primary endpoints included objective response rate (ORR), defined as partial response (PR) or complete response (CR), and disease-control rate, defined as PR, CR, or stable disease (SD). The secondary endpoints were progression-free survival (PFS), duration of response, and drug safety. Results: In the efficacy evaluation for all 27 patients, the ORR was 44.44% (95% CI: 24.4%-64.5%) and disease-control rate was 96.29% (95% CI: 88.7%-100%). Twelve cases (44.44%) achieved PR, 14 (51.85%) SD. The median PFS was 25.2 months (95% CI: 17.2 months to not reached). PFS was shorter in the anlotinib monotherapy group than in the group receiving anlotinib in combination with radionuclide therapy (P = .2). There were no serious treatment-related AEs. Conclusion: Anlotinib monotherapy or in combination with radionuclide therapies shows promising efficacy and safety for the treatment of LA/M PCC and PGL. Multi-tyrosine kinase inhibitors might represent a novel therapeutic strategy for patients with PPGL; however, large-scale prospective randomized, blinded, controlled clinical research studies are required.

Transcriptome data reveal beneficial effects of Rickettsia (Rickettsiales: Rickettsiaceae) on Bemisia tabaci(Hemiptera: Aleyrodidae) through nutritional factors and defense mechanisms.

Whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is a destructive insect pest of many crops. Rickettsia infection in different cryptic species of B. tabaci has been observed worldwide. Understanding the interactions between these 2 organisms is critical to developing Rickettsia-based strategies to control B. tabaci and thereby reduce the transmission of related vector-borne viruses. In this study, we investigated the effects of Rickettsia infection on the biological characteristics of the Middle East Asia Minor 1 (MEAM1) strain of B. tabaci through biological analysis of infected and uninfected individuals. The results of this study suggest that Rickettsia may confer fitness benefits. These benefits include increased fertility, improved survival rates, accelerated development, and resulted in female bias. We also investigated the transcriptomics impact of Rickettsia infection on B. tabaci by performing a comparative RNA-seq analysis of nymphs and adult females, both with and without the infection. Our analysis revealed 218 significant differentially expressed genes (DEGs) in infected nymphs compared to uninfected ones and 748 significant DEGs in infected female adults compared to their uninfected whiteflies. Pathway analysis further revealed that Rickettsia can affect many important metabolic pathways in whiteflies. The results suggest that Rickettsia plays an essential role in energy metabolism, and nutrient synthesis in the B. tabaci MEAM1, and depends on metabolites obtained from the host to ensure its survival. Overall, our findings suggest that Rickettsia has beneficial effects on B. tabaci and offered insights into the potential molecular mechanisms governing the interactions between Rickettsia and B. tabaci MEAM1.

Universal Intercalation/Alloying Hybrid Mechanism with -ICOHP Criterion in MAX Toward Steadily Ascending Lithium-Ion Batteries.

Profiting from the unique atomic laminated structure, metallic conductivity, and superior mechanical properties, transition metal carbides and nitrides named MAX phases have shown great potential as anodes in lithium-ion batteries. However, the complexity of MAX configurations poses a challenge. To accelerate such application, a minus integrated crystal orbital Hamilton populations descriptor is innovatively proposed to rapidly evaluate the lithium storage potential of various MAX, along with density functional theory computations. It confirms that surface A-element atoms bound to lithium ions have odds of escaping from MAX. Interestingly, the activated A-element atoms enhance the reversible uptake of lithium ions by MAX anodes through an efficient alloying reaction. As an experimental verification, the charge compensation and SnxLiy phase evolution of designed Zr2SnC MAX with optimized structure is visualized via in situ synchrotron radiation XRD and XAFS technique, which further clarifies the theoretically expected intercalation/alloying hybrid storage mechanism. Notably, Zr2SnC electrodes achieve remarkably 219.8% negative capacity attenuation over 3200 cycles at 1 A g-1. In principle, this work provides a reference for the design and development of advanced MAX electrodes, which is essential to explore diversified applications of the MAX family in specific energy fields.

HSPA12A maintains aerobic glycolytic homeostasis and Histone3 lactylation in cardiomyocytes to attenuate myocardial ischemia/reperfusion injury.

Myocardial ischemia/reperfusion (MI/R) injury is a major cause of adverse outcomes of revascularization following myocardial infarction. Anaerobic glycolysis during myocardial ischemia is well studied, but the role of aerobic glycolysis during the early phase of reperfusion is incompletely understood. Lactylation of Histone H3 (H3) is an epigenetic indicator of the glycolytic switch. Heat shock protein A12A (HSPA12A) is an atypic member of the HSP70 family. In the present study, we report that, during reperfusion following myocardial ischemia, HSPA12A was downregulated and aerobic glycolytic flux was decreased in cardiomyocytes. Notably, HSPA12A KO in mice exacerbated MI/R-induced aerobic glycolysis decrease, cardiomyocyte death, and cardiac dysfunction. Gain- and loss-of-function studies demonstrated that HSPA12A was required to support cardiomyocyte survival upon hypoxia/reoxygenation (H/R) challenge and that its protective effects were mediated by maintaining aerobic glycolytic homeostasis for H3 lactylation. Further analyses revealed that HSPA12A increased Smurf1-mediated Hif1α protein stability, thus increasing glycolytic gene expression to maintain appropriate aerobic glycolytic activity to sustain H3 lactylation during reperfusion and, ultimately, improving cardiomyocyte survival to attenuate MI/R injury.

Rickettsia transmission from whitefly to plants benefits herbivore insects but is detrimental to fungal and viral pathogens.

Bacterial endosymbionts play important roles in the life histories of herbivorous insects by impacting their development, survival, reproduction, and stress tolerance. How endosymbionts may affect the interactions between plants and insect herbivores is still largely unclear. Here, we show that endosymbiotic Rickettsia belli can provide mutual benefits also outside of their hosts when the sap-sucking whitefly Bemisia tabaci transmits them to plants. This transmission facilitates the spread of Rickettsia but is shown to also enhance the performance of the whitefly and co-infesting caterpillars. In contrast, Rickettsia infection enhanced plant resistance to several pathogens. Inside the plants, Rickettsia triggers the expression of salicylic acid-related genes and the two pathogen-resistance genes TGA 2.1 and VRP, whereas they repressed genes of the jasmonic acid pathway. Performance experiments using wild type and mutant tomato plants confirmed that Rickettsia enhances the plants' suitability for insect herbivores but makes them more resistant to fungal and viral pathogens. Our results imply that endosymbiotic Rickettsia of phloem-feeding insects affects plant defenses in a manner that facilitates their spread and transmission. This novel insight into how insects can exploit endosymbionts to manipulate plant defenses also opens possibilities to interfere with their ability to do so as a crop protection strategy. IMPORTANCE: Most insects are associated with symbiotic bacteria in nature. These symbionts play important roles in the life histories of herbivorous insects by impacting their development, survival, reproduction as well as stress tolerance. Rickettsia is one important symbiont to the agricultural pest whitefly Bemisia tabaci. Here, for the first time, we revealed that the persistence of Rickettsia symbionts in tomato leaves significantly changed the defense pattern of tomato plants. These changes benefit both sap-feeding and leaf-chewing herbivore insects, such as increasing the fecundity of whitefly adults, enhancing the growth and development of the noctuid Spodoptera litura, but reducing the pathogenicity of Verticillium fungi and TYLCV virus to tomato plants distinctively. Our study unraveled a new horizon for the multiple interaction theories among plant-insect-bacterial symbionts.

Biotechnological production of ectoine: current status and prospects.

Ectoine is an important natural secondary metabolite in halophilic microorganisms. It protects cells against environmental stressors, such as salinity, freezing, drying, and high temperatures. Ectoine is widely used in medical, cosmetic, and other industries. Due to the commercial market demand of ectoine, halophilic microorganisms are the primary method for producing ectoine, which is produced using the industrial fermentation process "bacterial milking." The method has some limitations, such as the high salt concentration fermentation, which is highly corrosive to the equipment, and this also increases the difficulty of downstream purification and causes high production costs. The ectoine synthesis gene cluster has been successfully heterologously expressed in industrial microorganisms, and the yield of ectoine was significantly increased and the cost was reduced. This review aims to summarize and update microbial production of ectoine using different microorganisms, environments, and metabolic engineering and fermentation strategies and provides important reference for the development and application of ectoine.

Anion Additive Integrated Electric Double Layer and Solvation Shell for Aqueous Zinc Ion Battery.

Aqueous zinc ion batteries (AZIBs) show great potential in large-scale energy storage systems. However, the inferior cycling life due to water-induced parasitic reactions and uncontrollable dendrites growth impede their application. Electrolyte optimization via the use of additives is a promising strategy to enhance the stability of AZIBs. Nevertheless, the mechanism of optimal multifunctional additive strategy requires further exploration. Herein, sodium dodecyl benzene sulfonate (SDBS) is proposed as a dual-functional additive in ZnSO4 electrolyte. Benefiting from the additive, both side reactions and zinc dendrites growth are significantly inhibited. Further, a synchrotron radiational spectroscopic study is employed to investigate SDB- adjusted electric double layer (EDL) near the Zn surface and the optimized solvation sheath of Zn2+. First-principles calculations verify the firm adsorption of SDB-, and restriction of random diffusion of Zn2+ on the Zn surface. In particular, the SDBS additive endows Zn||Zn symmetric cells with a 1035 h ultra-stable plating/stripping at 0.2 mA cm-2. This work not only provides a promising design strategy by dual-functional electrolyte additives for high stable AZIBs, but also exhibits the prospect of synchrotron radiation spectroscopy analysis on surface EDL and Zn2+ solvation shell optimization.

PET/NIR Fluorescence Bimodal Imaging for Targeted Tumor Detection.

Cancer is one of the greatest threats to human health due to late diagnosis and incomplete resection. The bimodal probe combines positron emission tomography (PET) imaging for noninvasive whole-body scanning with intraoperative near-infrared fluorescence (NIRF) surgical guidance for preoperative tumor detection, tumor resection during surgery, and postoperative monitoring. We developed a new PET/NIRF bimodal imaging agent, [68Ga]Ga-DOTA-NPC, covalently coupled to DCDSTCY and DOTA via ethylenediamine and radiolabeled with gallium-68, and investigated it in vitro and in vivo. The probe was found to be preferential for colon cancer cells due to the organic anion-transporting polypeptide1B3 (OATP1B3). PET/NIRF imaging allowed us to confirm [68Ga]Ga-DOTA-NPC as a promising probe for tumor detection, as it provides good biosafety and high-contrast tumor accumulation. Orthotopic and subcutaneous colon tumors were successfully resected under real-time NIRF guidance. [68Ga]Ga-DOTA-NPC provides highly sensitive and unlimited tissue-penetrating PET/NIRF imaging, helping to visualize and differentiate tumors from adjacent tissue.

Structural Integrity Assessment of an NEPE Propellant Grain Considering the Tension-Compression Asymmetry in Its Mechanical Property.

In order to investigate the effect of tension-compression asymmetry of propellant mechanical properties on the structural integrity of a Nitrate Ester Plasticized Polyether (NEPE) propellant grain, the unified constitutive equations under tension and compression were established, a new method for grain structural integrity assessment was proposed and the structural integrity of the NEPE propellant grain under the combined axial and transverse overloads was evaluated. The results indicate that the mechanical state of the NEPE propellant grain is in the coexistence of tension and compression under the combined axial and transverse overloads, and the tension and compression regions in the propellant grain is independent of the propellant constitutive behavior. The tension-compression asymmetry of the propellant mechanical properties has a certain impact on its mechanical response. The maximum equivalent stress and strain considering the tension-compression asymmetry falls between that obtained through the tension and compression constitutive model, and is the same as damage coefficient. The safety factor of the NEPE propellant grain considering the tension-compression asymmetry of its mechanical properties is larger than that non-considering, and the traditional method of structural integrity assessment is conservative.

Mealybug salivary microbes inhibit induced plant defenses.

BACKGROUND: Phenacoccus solenopsis is a polyphagous invasive mealybug that caused serious damage to crops worldwide. Phloem-sucking hemipterans are known to carry symbiotic microbes in their saliva. However, the role of salivary bacteria of P. solenopsis in modulating plant defenses remains limited. Exploring the impact of salivary bacteria on plant defense responses will contribute to the development of new targets for efficient control of invasive mealybugs. RESULTS: Salivary bacteria of the invasive mealybug P. solenopsis can suppress herbivore-induced plant defenses and thus enhance mealybug fitness. Mealybugs treated with an antibiotic showed decreased weight gain, fecundity and survival. Untreated mealybugs suppressed jasmonic acid (JA)-regulated defenses but activated salicylic acid (SA)-regulated defenses in cotton plants. In contrast, antibiotic-treated mealybugs triggered JA-responsive gene expression and JA accumulation, and showed shortened phloem ingestion. Reinoculating antibiotic-treated mealybugs with Enterobacteriaceae or Stenotrophomonas cultivated from mealybug saliva promoted phloem ingestion and fecundity, and restored the ability of mealybugs to suppress plant defenses. Fluorescence in situ hybridization visualization revealed that Enterobacteriaceae and Stenotrophomonas colonize salivary glands and are secreted into the mesophyll cells and phloem vessels. Exogenous application of the bacterial isolates to plant leaves inhibited JA-responsive gene expression and activated SA-responsive gene expression. CONCLUSION: Our findings imply that symbiotic bacteria in the saliva of the mealybug play an important role in manipulating herbivore-induced plant defenses, enabling this important pest to evade induced plant defenses and promoting its performance and destructive effects on crops. © 2023 Society of Chemical Industry.

Diagnostic value of matrix metalloproteinases 2, 7 and 9 in urine for early detection of colorectal cancer.

BACKGROUND: A noninvasive biomarker with high diagnostic performance is urgently needed for the early diagnosis of colorectal cancer (CRC). AIM: To evaluate the diagnostic value of matrix metalloproteinases (MMPs) 2, 7 and 9 in urine for CRC. METHODS: Of 59 healthy controls, 47 patients with colon polyps and 82 patients with CRC were included in this study. Carcinoembryonic antigen (CEA) in serum and MMP2, MMP7, and MMP9 in urine were detected. The combined diagnostic model of the indicators was established by binary logistic regression. The receiver operating characteristic curve (ROC) of the subjects was used to evaluate the independent and combined diagnostic value of the indicators. RESULTS: The MMP2, MMP7, MMP9, and CEA levels in the CRC group differed significantly from levels in the healthy controls (P < 0.05). The levels of MMP7, MMP9, and CEA also differed significantly between the CRC group and the colon polyps group (P < 0.05). The area under the curve (AUC) distinguishing between the healthy control and the CRC patients using the joint model with CEA, MMP2, MMP7 and MMP9 was 0.977, and the sensitivity and specificity were 95.10% and 91.50%, respectively. For early-stage CRC, the AUC was 0.975, and the sensitivity and specificity were 94.30% and 98.30%, respectively. For advanced stage CRC, the AUC was 0.979, and the sensitivity and specificity were 95.70% and 91.50%, respectively. Using CEA, MMP7 and MMP9 to jointly established a model distinguishing the colorectal polyp group from the CRC group, the AUC was 0.849, and the sensitivity and specificity were 84.10% and 70.20%, respectively. For early-stage CRC, the AUC was 0.818, and the sensitivity and specificity were 76.30% and 72.30%, respectively. For advanced stage CRC, the AUC was 0.875, and the sensitivity and specificity were 81.80% and 72.30%, respectively. CONCLUSION: MMP2, MMP7 and MMP 9 may exhibit diagnostic value for the early detection of CRC and may serve as auxiliary diagnostic markers for CRC.

Operando Exploring and Modulating Phase Evolution Chemistry from MAX to MXenes in Molten Salt Synthesis.

Lewis acidic molten salt method is a promising synthesis strategy for achieving MXenes with controllable surface termination from numerous MAX materials. Understanding the phase evolution chemistry during etching and post-processing is highly desirable but remains a key challenge due to the lack of suitable in-situ characterizations and the complexity of the reaction process. Herein, we introduce an operando synchrotron radiation X-ray diffraction (SRXRD) technique to unveil the phase evolution process of Nb2GaC MAX under a molten-salt ambient, proposing a controllable synthesis to achieve optimal etching through precise temperature and time adjustment. Subsequently, the phase structure of Nb2CTx MXenes is successfully tailored from hexagonal to amorphous by time-dependent persulfate oxidation. The resulting amorphous Nb2CTx with a well-patterned morphology and numerous chloride terminations exhibits highly improved specific capacity, rate capability, and long cycling for Li+ storage with a Cl-containing surface protective film. Addressing the time-related phase evolution during the entire molten salt strategy provides new insights into achieving higher efficiency and controllability in preparing MXenes and shows great potential in high-performance energy storage systems based on MXenes.

Asymmetrically Coordinated CoB1 N3 Moieties for Selective Generation of High-Valence Co-Oxo Species via Coupled Electron-Proton Transfer in Fenton-like Reactions.

High-valence metal species generated in peroxymonosulfate (PMS)-based Fenton-like processes are promising candidates for selective degradation of contaminants in water, the formation of which necessitates the cleavage of OH and OO bonds as well as efficient electron transfer. However, the high dissociation energy of OH bond makes its cleavage quite challenging, largely hampering the selective generation of reactive oxygen species. Herein, an asymmetrical configuration characterized by a single cobalt atom coordinated with boron and nitrogen (CoB1 N3 ) is established to offer a strong local electric field, upon which the cleavage of OH bond is thermodynamically favored via a promoted coupled electron-proton transfer process, which serves an essential step to further allow OO bond cleavage and efficient electron transfer. Accordingly, the selective formation of Co(IV)O in a single-atom Co/PMS system enables highly efficient removal performance toward various organic pollutants. The proposed strategy also holds true in other heteroatom doping systems to configure asymmetric coordination, thus paving alternative pathways for specific reactive species conversion by rationalized design of catalysts at atomic level toward environmental applications and more.

Intercalant-induced V t2g orbital occupation in vanadium oxide cathode toward fast-charging aqueous zinc-ion batteries.

Intercalation-type layered oxides have been widely explored as cathode materials for aqueous zinc-ion batteries (ZIBs). Although high-rate capability has been achieved based on the pillar effect of various intercalants for widening interlayer space, an in-depth understanding of atomic orbital variations induced by intercalants is still unknown. Herein, we design an NH4+-intercalated vanadium oxide (NH4+-V2O5) for high-rate ZIBs, together with deeply investigating the role of the intercalant in terms of atomic orbital. Besides extended layer spacing, our X-ray spectroscopies reveal that the insertion of NH4+ could promote electron transition to 3dxy state of V t2g orbital in V2O5, which significantly accelerates the electron transfer and Zn-ion migration, further verified by DFT calculations. As results, the NH4+-V2O5 electrode delivers a high capacity of 430.0 mA h g-1 at 0.1 A g-1, especially excellent rate capability (101.0 mA h g-1 at 200 C), enabling fast charging within 18 s. Moreover, the reversible V t2g orbital and lattice space variation during cycling are found via ex-situ soft X-ray absorption spectrum and in-situ synchrotron radiation X-ray diffraction, respectively. This work provides an insight at orbital level in advanced cathode materials.

X-ray Insights into Formation of -O Functional Groups on MXenes: Two-Step Dehydrogenation of Adsorbed Water.

Engineered MXene surfaces with more -O functional groups are feasible for realizing higher energy density due to their higher theoretical capacitance. However, there have been only a few explorations of this regulation mechanism. Investigating the formation source and mechanism is conducive to expanding the adjustment method from the top-down perspective. Herein, for the first time, the formation dynamics of -O functional groups on Mo2CTx are discovered as a two-step dehydrogenation of adsorbed water through in situ near-ambient-pressure X-ray photoelectron spectroscopy, further confirmed by ab initio molecular dynamics simulations. From this, the controllable substitution of -F functional groups with -O functional groups is achieved on Mo2CTx during electrochemical cycling in an aqueous electrolyte. The obtained Mo2CTx with rich -O groups exhibits a high capacitance of 163.2 F g -1 at 50 mV s -1, together with excellent stability. These results offer new insights toward engineering surface functional groups of MXenes for many specific applications.

Monolayer Thiol Engineered Covalent Interface toward Stable Zinc Metal Anode.

Interface engineering of zinc metal anodes is a promising remedy to relieve their inferior stability caused by dendrite growth and side reactions. Nevertheless, the low affinity and additional weight of the protective coating remain obstacles to their further implementation. Here, aroused by DFT simulation, self-assembled monolayers (SAMs) are selectively constructed to enhance the stability of zinc metal anodes in dilute aqueous electrolytes. It is found that the monolayer thiol molecules relatively prefer to selectively graft onto the unstable zinc crystal facets through strong Zn-S chemical interactions to engineer a covalent interface, enabling the uniform deposition of Zn2+ onto (002) crystal facets. Therefore, dendrite-free anodes with suppressed side reactions can be achieved, proven by in situ optical visualization and differential electrochemical mass spectrometry (DEMS). In particular, the thiol endows the symmetric cells with a 4000 h ultrastable plating/stripping at a specific current density of 1.0 mA cm-2, much superior to those of bare zinc anodes. Additionally, the full battery of modified anodes enables stable cycling of 87.2% capacity retention after 3300 cycles. By selectively capping unstable crystal facets with inert molecules, this work provides a promising design strategy at the molecular level for stable metal anodes.