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The growing global energy demand necessitates the development of renewable energy solutions to mitigate greenhouse gas emissions and air pollution. To efficiently utilize renewable yet intermittent energy sources such as solar and wind power, there is a critical need for large-scale energy storage systems (EES) with high electrochemical performance. While lithium-ion batteries (LIBs) have been successfully used for EES, the surging demand and price, coupled with limited supply of crucial metals like lithium and cobalt, raised concerns about future sustainability. In this context, potassium-ion batteries (PIBs) have emerged as promising alternatives to commercial LIBs. Leveraging the low cost of potassium resources, abundant natural reserves, and the similar chemical properties of lithium and potassium, PIBs exhibit excellent potassium ion transport kinetics in electrolytes. This review starts from the fundamental principles and structural regulation of PIBs, offering a comprehensive overview of their current research status. It covers cathode materials, anode materials, electrolytes, binders, and separators, combining insights from full battery performance, degradation mechanisms, in situ/ex situ characterization, and theoretical calculations. We anticipate that this review will inspire greater interest in the development of high-efficiency PIBs and pave the way for their future commercial applications.
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The small molecule epiberberine (EPI) is a natural alkaloid with versatile bioactivities against several diseases including cancer and bacterial infection. EPI can induce the formation of a unique binding pocket at the 5' side of a human telomeric G-quadruplex (HTG) sequence with four telomeric repeats (Q4), resulting in a nanomolar binding affinity (KD approximately 26 nM) with significant fluorescence enhancement upon binding. It is important to understand (1) how EPI binding affects HTG structural stability and (2) how enhanced EPI binding may be achieved through the engineering of the DNA binding pocket. In this work, the EPI-binding-induced HTG structure stabilization effect was probed by a peptide nucleic acid (PNA) invasion assay in combination with a series of biophysical techniques. We show that the PNA invasion-based method may be useful for the characterization of compounds binding to DNA (and RNA) structures under physiological conditions without the need to vary the solution temperature or buffer components, which are typically needed for structural stability characterization. Importantly, the combination of theoretical modeling and experimental quantification allows us to successfully engineer Q4 derivative Q4-ds-A by a simple extension of a duplex structure to Q4 at the 5' end. Q4-ds-A is an excellent EPI binder with a KD of 8 nM, with the binding enhancement achieved through the preformation of a binding pocket and a reduced dissociation rate. The tight binding of Q4 and Q4-ds-A with EPI allows us to develop a novel magnetic bead-based affinity purification system to effectively extract EPI from Rhizoma coptidis (Huang Lian) extracts.
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Berberina , Quadruplex G , Berberina/química , Berberina/análogos & derivados , Berberina/farmacologia , Humanos , DNA/química , Ácidos Nucleicos Peptídicos/químicaRESUMO
Rechargeable potassium-ion batteries (PIBs) are regarded as potential substitutes for industrial lithium-ion batteries in large scale energy storage systems due to the world's abundant potassium supplies. Althogh cobalt hexacyanocobaltate (CoHCC) exhibits broad potential as a PIB anode material, its performance is currently unsatisfactory. Herein, novel 5 nm scale ultrathin CoHCC nanosheet-assembled nanoboxes with interspersed carbon nanotubes (CNTs/CoHCC nanoboxes) are fabricated to realize a highly reactive PIB anode. The ultrathin CoHCC layers substantially accelerate electron conduction and provide numerous active sites, while the connected CNTs provide fast axial electron transport. Consequently, the optimized anode exhibits a remarkable discharge capacity of 580.9 mAh g-1 at 0.1 A g-1 and long-term stability with 71.3% retention over 1000 cycles. In situ and ex situ characterizations and density functional theory calculations are further employed to elucidate the K+ storage process and the reason for the enhanced performance of the CNTs/CoHCC nanoboxes.
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Peptidomics was employed to systematically analyze the characteristic peptides in Galli Gigerii Endothelium Corneum and its adulterants and establish a method for distinguishing Galli Gigerii Endothelium Corneum from its adulterants, including the gizzard membranes from ducks, geese, and pigeons. UPLC-Q-Exactive Orbitrap-MS was combined with multivariate statistical analysis to analyze the peptides in Galli Gigerii Endothelium Corneum and its adulterants. The structures of peptides were identified by pNovo combined with manual recognition of spectra, and synthetic peptide standards were used for validation. LC-MS/MS was used to optimize the sample pre-processing conditions, including the extraction procedure, extraction time, extraction solvents, and solvent volumes, for the characteristic peptide LESY in Galli Gigerii Endothelium Corneum. Multiple reaction monitoring(MRM) in the ESI~+ mode with m/z 511.24â269.11 and 511.24â243.13 as detection ions was employed for qualitative and quantitative analyses. The established UPLC-MS/MS method demonstrated good specificity, stability, and durability. The content of LESY in 16 batches of Galli Gigerii Endothelium Corneum samples ranged from 55.03 to 113.36 µg·g~(-1). Additionally, a qualitative detection method for the common peptide RDPVLVSR in adulterants was established with m/z 471.28â785.45 and 471.28â670.41 as the detection ions. This study established a convenient, rapid, and accurate detection method for the characteristic peptides in Galli Gigerii Endothelium Corneum and its adulterants. The method possesses good specificity, stability, and durability, providing a valuable reference for the identification and quality control of Galli Gigerii Endothelium Corneum and other traditional Chinese medicines derived from animal sources.
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Peptídeos , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Peptídeos/química , Peptídeos/análise , Endotélio/química , Galinhas , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Proteômica/métodos , Contaminação de Medicamentos , Espectrometria de Massa com Cromatografia LíquidaRESUMO
Spinel oxides have emerged as highly active catalysts for the oxygen evolution reaction (OER). However, due to covalency competition, the OER process on spinel oxides often follows an arduous adsorbate evolution mechanism (AEM) pathway. Herein, we propose a novel rare-earth sites substitution strategy to tune the lattice oxygen redox of spinel oxides and bypass the AEM scaling relationship limitation. Taking NiCo2O4 as a model, the incorporation of Ce into the octahedral site induces the formation of Ce-O-M (M: Ni, Co) bridge, which triggers charge redistribution in NiCo2O4. The developed Ce-NiCo2O4 exhibits remarkable OER activity with a low overpotential, satisfactory electrochemical stability, and good practicability in anion-exchange membrane water electrolyzer. Theoretical analyses reveal that OER on Ce-NiCo2O4 surface follows a more favorable lattice oxygen mechanism (LOM) pathway and non-concerted proton-electron transfers compared to pure NiCo2O4, as further verified by pH-dependent behavior and in situ Raman analysis. 18O-labeled electrochemical mass spectrometry directly demonstrates that oxygen originates from the lattice oxygen of Ce-NiCo2O4 during OER. It is discovered that electron delocalization of Ce 4f states triggers charge redistribution in NiCo2O4 through the Ce-O-M bridge, favoring antibonding state occupation of Ni-O bonding in [Ce-O-Ni] site, thereby activating lattice oxygen redox of NiCo2O4 in OER.
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The development of atomically dispersed iron-nitrogen-carbon (FeâNâC) catalysts as an alternative to precious platinum holds great potential for the substantial progress of a variety of oxygen reduction reaction (ORR)-associated energy conversion technologies. Nevertheless, the precise synthesis of FeâNâC single atomic catalysts (SACs) with a high density of accessible active sites and pronounced electrocatalytic performance still remains an enormous challenge. Herein, an innovative extended Stöber method is designed for the controllable preparation of monodisperse small-sized N-doped carbon colloidal nanospheres (≈40 nm) anchoring atomically isolated FeâN4 sites (abbreviated as Fe-SA@N-CNSs hereafter) with a narrow size distribution and high uniformity. Benefiting from the single FeâN4 moieties and the unique spherical carbon substrate, the resultant Fe-SA@N-CNSs exhibit excellent ORR activity, outstanding long-term durability, and methanol tolerance in KOH electrolyte. More impressively, when further assembled into a flexible solid-state rechargeable zinc-air battery (ZAB), the Fe-SA@N-CNSs-driven ZAB delivers a higher open circuit voltage, a larger power density, and robust cycling/mechanical stability, outperforming the state-of-the-art Pt/C-based counterpart and further testifying the great potential of the as-prepared Fe-SA@N-CNSs in diverse ORR-related practical energy devices. The developed extended Stöber method provides an efficient and versatile avenue toward the preparation of a series of well-defined SACs for diverse electrocatalytic systems.
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Layered double-hydroxide (LDH) has been considered an important class of electrocatalysts for the oxygen evolution reaction (OER), but the adsorption-desorption behaviors of oxygen intermediates on its surface still remain unsatisfactory. Apart from transition-metal doping to solve this electrocatalytic problem of LDH, rare-earth (RE) species have sprung up as emerging dopants owing to their unique 4f valence-electronic configurations. Herein, the Er is chosen as a RE model to improve OER activity of LDH via constructing nickel foam supported Er-doped NiFe-LDH catalyst (Er-NiFe-LDH@NF). The optimal Er-NiFe-LDH@NF exhibits a low overpotential (191 mV at 10 mA cm-2 ), high turnover frequency (0.588 s-1 ), and low activation energy (36.03 kJ mol-1 ), which are superior to Er-free sample. Electrochemical in situ Raman spectra reveal the facilitated transition of Ni-OH into Ni-OOH for promoted OER kinetics through the Er doping effect. Theoretical calculations demonstrate that the introduction of Er facilitates the spin crossover of valence electrons by optimizing the d band center of NiFe-LDH, which leads to the GO -GHO closer to the optimal activity of the kinetic OER volcano by balancing the bonding strength of *O and *OH. Moreover, the Er-NiFe-LDH@NF presents high practicability in electrochemical water-splitting devices with a low driving potential of and a well-extended driving period.
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OBJECTIVES: To explore the auxiliary value of combining CT features with existing response evaluation criteria in the prediction of progressive disease (PD) in gastrointestinal stromal tumors (GIST) patients treated with sunitinib. MATERIAL AND METHODS: Eighty-one patients with GISTs who received sunitinib were included in this retrospective multicenter study and divided into training and external validation cohorts. Progression at six months was determined as a reference standard. The predictive performance of the RECIST 1.1 and Choi criteria was compared. CT features at baseline and the first follow-up were analyzed. Logistic regression analyses were used to determine the most significant predictors and develop modified criteria. RESULTS: A total of 216 lesions showed a good response and 107 showed a poor response in 81 patients. The RECIST 1.1 criteria performed better than the Choi criteria in predicting progression (AUC, 0.75 vs. 0.69, p = 0.04). The expanded/intensified high-enhancement area, blurred tumor-tissue interface, and progressive enlarged vessels feeding or draining the mass (EVFDM) differed significantly between lesions with good and poor responses in the training cohort (p = 0.001, 0.003, and 0.000, respectively). Multivariate analysis revealed that the expanded/intensified high-enhancement area (p = 0.001), progressive EVFDM (p = 0.000), and RECIST PD (p = 0.000) were independent predictive factors. Modified RECIST (mRECIST) criteria were developed and showed significantly higher AUCs in the training and external validation cohorts than the RECIST 1.1 criteria (training: 0.81 vs. 0.73, p = 0.002; validation: 0.82 vs. 0.77, p = 0.04). CONCLUSION: The mRECIST criteria, combining CT features with the RECIST 1.1 criteria, demonstrated superior performance in the prediction of early progression in GIST patients receiving sunitinib. CLINICAL RELEVANCE STATEMENT: The mRECIST criteria, which combine CT features with the RECIST 1.1 criteria, may facilitate the early detection of progressive disease in GIST patients treated with sunitinib, thereby potentially guiding the timely switch to late-line medications or combination with surgical excision. KEY POINTS: ⢠The RECIST 1.1 criteria outperformed the Choi criteria in identifying progression of GISTs in patients treated with sunitinib. ⢠GISTs displayed different morphologic features on CT depending on how they responded to sunitinib. ⢠Combining CT morphologic features with the RECIST 1.1 criteria allowed for the prompt and accurate identification of progressing GIST lesions.
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PURPOSE: Inpatient mortality is an important variable in epidemiology studies using claims data. In 2016, MarketScan data began obscuring specific hospital discharge status types for patient privacy, including inpatient deaths, by setting the values to missing. We used a machine learning approach to correctly identify hospitalizations that resulted in inpatient death using data prior to 2016. METHODS: All hospitalizations from 2011 to 2015 with discharge status of missing, died, or one of the other subsequently obscured values were identified and divided into a training set and two test sets. Predictor variables included age, sex, elapsed time from hospital discharge until last observed claim and until healthcare plan disenrollment, and absence of any discharge diagnoses. Four machine learning methods were used to train statistical models and assess sensitivity and positive predictive value (PPV) for inpatient mortality. RESULTS: Overall 1 307 917 hospitalizations were included. All four machine learning approaches performed well in all datasets. Random forest performed best with 88% PPV and 93% sensitivity for the training set and both test sets. The two factors with the highest relative importance for identifying inpatient mortality were having no observed claims for the patient on days 2-91 following hospital discharge and patient disenrollment from the healthcare plan within 60 days following hospital discharge. CONCLUSION: We successfully developed machine learning algorithms to identify inpatient mortality. This approach can be applied to obscured data to accurately identify inpatient mortality among hospitalizations with missing discharge status.
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Pacientes Internados , Aprendizado de Máquina , Humanos , Algoritmos , Hospitalização , Alta do Paciente , Estudos RetrospectivosRESUMO
The active-site density, intrinsic activity, and durability of Pd-based materials for oxygen reduction reaction (ORR) are critical to their application in industrial energy devices. This work constructs a series of carbon-based rare-earth (RE) oxides (Gd2 O3 , Sm2 O3 , Eu2 O3 , and CeO2 ) by using RE metal-organic frameworks to tune the ORR performance of the Pd sites through the Pd-REx Oy interface interaction. Taking Pd-Gd2 O3 /C as a representative, it is identified that the strong coupling between Pd and Gd2 O3 induces the formation of the Pd-O-Gd bridge, which triggers charge redistribution of Pd and Gd2 O3 . The screened Pd-Gd2 O3 /C exhibits impressive ORR performance with high onset potential (0.986 VRHE ), half-wave potential (0.877â VRHE ), and excellent stability. Similar ORR results are also found for Pd-Sm2 O3 /C, Pd-Eu2 O3 /C, and Pd-CeO2 /C catalysts. Theoretical analyses reveal that the coupling between Pd and Gd2 O3 promotes electron transfer through the Pd-O-Gd bridge, which induces the antibonding-orbital occupancy of Pd-*OH for the optimization of *OH adsorption in the rate-determining step of ORR. The pH-dependent microkinetic modeling shows that Pd-Gd2 O3 is close to the theoretical optimal activity for ORR, outperforming Pt under the same conditions. By its ascendancy in ORR, the Pd-Gd2 O3 /C exhibits superior performance in Zn-air battery as an air cathode, implying its excellent practicability.
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Designing affordable and efficient bifunctional electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) has remained a long-lasting target for the progressing hydrogen economy. Utilization of metal/semiconductor interface effect has been lately established as a viable implementation to realize the favorable electrocatalytic performance due to the built-in electric field. Herein, a typical Mott-Schottky electrocatalyst by immobilizing Ni/CeO2 hetero-nanoparticles onto N-doped carbon nanofibers (abbreviated as Ni/CeO2 @N-CNFs hereafter) has been developed via a feasible electrospinning-carbonization tactic. Experimental findings and theoretic calculations substantiate that the elaborated constructed Ni/CeO2 heterojunction effectively triggers the self-driven charge transfer on heterointerfaces, leading to the promoted charge transfer rate, the optimized chemisorption energies for reaction intermediates and ultimately the expedited reaction kinetics. Therefore, the well-designed Ni/CeO2 @N-CNFs deliver superior HER and OER catalytic activities with overpotentials of 100 and 230 mV at 10 mA cm-2 , respectively, in alkaline solution. Furthermore, the Ni/CeO2 @N-CNFs-equipped electrolyzer also exhibits a low cell voltage of 1.56 V to attain 10 mA cm-2 and impressive long-term durability over 55 h. The innovative manipulation of electronic modulation via Mott-Schottky establishment may inspire the future development of economical electrocatalysts for diverse sustainable energy systems.
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An dual electronic and architectural engineering strategy is a good way to rationally design earth-abundant and highly efficient electrocatalysts of the oxygen evolution reaction (OER) for sustainable hydrogen-based energy devices. Here, a Ce-doped Co9 S8 core-shell nanoneedle array (Ce-Co9 S8 @CC) supported on a carbon cloth has been designed and developed to accelerate the sluggish kinetics of the OER. Profiting from valance alternative Ce doping, a fine core-shell structure and vertically aligned nanoneedle arrayed architecture, Ce-Co9 S8 @CC integrates modulated electronic structure, highly exposed active sites, and multidimensional mass diffusion channels; together, these afford a favorable catalyzed OER. Ce-Co9 S8 @CC exhibits remarkable performance in the OER in an alkaline medium, where the overpotential requires only 242â mV to deliver a current density of 10â mA cm-2 for the OER; this is 70â mV superior to that of Ce-free Co9 S8 catalyst and other counterparts. Good stability and impressive selectivity (nearly 100 % Faradic efficiency) are also demonstrated. When integrated into a two-electrode OER//HER electrolyzer, the as-prepared Ce-Co9 S8 @CC displays a low operation potential of 1.54â V at 10â mA cm-2 and long-term stability, thus demonstrating great potential for economical water electrolysis.
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YccA is a hydrophobic protein with seven transmembrane domains. The function of YccA is largely unknown in pathogenic bacteria. Edwardsiella piscicide (formerly known as E. tarda) is an aquatic pathogen that can infect various economically important fish, including flounder (Paralichthys olivaceus) and tilapia (Oreochromis niloticus). In this study, we investigated the role of YccA in E. piscicida by the construction of a mar kerless yccA in-frame mutant strain, TX01ΔyccA. We found that (i) in comparison to the wild type TX01, TX01ΔyccA exhibited markedly compromised tolerance to high temperature and tobramycin; (ii) deletion of yccA significantly impaired the integrity of the cell membrane and retarded bacterial biofilm formation and mobility; (iii) deficiency of yccA reduced bacterial adhesion and invasion of fish cells and immune tissues, while the introduction of a trans-expressed yccA gene restored the lost virulence of TX01ΔyccA; and (iv) host immune responses induced by TX01 and TX01ΔyccA were different in terms of reactive oxygen species (ROS) levels and expression levels of cytokines. Taken together, the results of our study indicate that YccA is a novel virulence factor of E. piscicida, and YccA is essential for bacterial pathogenicity through evasion of the host's innate immune functions.
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Edwardsiella , Infecções por Enterobacteriaceae , Doenças dos Peixes , Linguado , Animais , Proteínas de Bactérias/genética , Edwardsiella/fisiologia , Edwardsiella tarda , Linguado/metabolismo , Imunidade , Virulência/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismoRESUMO
BACKGROUND: Interleukin 1 inhibition with anakinra has shown efficacy in the management of crystalline-induced arthritis (CIA) flares. Gout treatment guidelines recommend its use after contraindication or intolerance to first-line therapies. The aim of this study is to identify features associated with better response to anakinra when used to treat CIA flares. METHODS: This is a medical record review study that included inpatients with acute CIA in whom anakinra was used between the years 2014 and 2019 at one tertiary center (University of Alabama at Birmingham). The primary end point was response to anakinra treatment defined as a decrease in the reported visual analog score of at least 50% within 48 hours of initiation of treatment. Demographic, clinical, and laboratory factors were compared, and factors found significant in bivariate analysis at a p value of less than 0.15 were tested in a multivariate logistic regression analysis for independent association with the response. RESULTS: A total of 55 admission encounters were analyzed. The mean age was 60.1 years, 36 (66%) were men, and 31 (56%) were African Americans. Twenty-eight of 49 (57%) met the primary end point of response at 48 hours, but 52 of 55 (94.5%) ultimately responded to anakinra during hospital stay. Factors associated with response at 48 hours were race, reason for admission related to cardiac etiologies, not having failed steroids before trial of anakinra, and hospital admission within 48 hours of initiation of flare. On a multivariable logistic regression model, we could not find significant independent associations with response to anakinra. CONCLUSIONS: Our study showed high response rates to anakinra. We could not identify factors associated with a more robust, early response. It is likely that anakinra is equally effective across a wide range of clinical scenarios.
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Antirreumáticos , Artropatias por Cristais , Gota , Antirreumáticos/uso terapêutico , Feminino , Gota/tratamento farmacológico , Hospitalização , Humanos , Proteína Antagonista do Receptor de Interleucina 1/efeitos adversos , Interleucina-1 , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND/PURPOSE: The aim of this study was to compare the clinical features at presentation of ANCA-associated vasculitis (AAV) between African American (AA) and White patients. METHODS: This is a chart review of cases between January 2003 and December 2018. African American patients with AAV were identified and matched in a 1:2 ratio with White comparators based on the year of diagnosis (±4 years). Data on demographics, clinical, and laboratory features and outcomes at presentation were collected. Descriptive statistics were used to compare the characteristics between groups. RESULTS: Thirty-two of 56 AA patients with AAV had complete data and were included for analysis. When compared with 64 matched White patients with AAV, AA patients were younger (47.5 vs 61.0 years, p = 0.001). Compared with White patients, AA patients with granulomatosis with polyangiitis (GPA) (35 vs 55 years, p = 0.0006) and microscopic polyangiitis (MPA) (55.5 vs 65.0 years, p = 0.05) were younger. African American patients with GPA were more frequently female (p = 0.008), whereas AA patients with MPA were more frequently male (p = 0.03). No differences in disease manifestations, disease activity, and outcomes were observed between AA and White patients with AAV. CONCLUSIONS: In this single-center study, AA patients with AAV were diagnosed at a younger age than Whites; this was found in both the GPA and MPA disease phenotypes. No other significant differences were observed. Future studies are needed to confirm our findings and better describe differences of AAV in racial/ethnic minorities.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Granulomatose com Poliangiite , Poliangiite Microscópica , Negro ou Afro-Americano , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/epidemiologia , Anticorpos Anticitoplasma de Neutrófilos , Feminino , Granulomatose com Poliangiite/diagnóstico , Humanos , Masculino , Prontuários Médicos , Poliangiite Microscópica/diagnóstico , Estados Unidos/epidemiologiaRESUMO
Ruthenium (Ru) has been theoretically considered a viable alkaline hydrogen evolution reaction electrocatalyst due to its fast water dissociation kinetics. However, its strong affinity to the adsorbed hydroxyl (OHad ) blocks the active sites, resulting in unsatisfactory performance during the practical HER process. Here, we first reported a competitive adsorption strategy for the construction of SnO2 nanoparticles doped with Ru single-atoms supported on carbon (Ru SAs-SnO2 /C) via atomic galvanic replacement. SnO2 was introduced to regulate the strong interaction between Ru and OHad by the competitive adsorption of OHad between Ru and SnO2 , which alleviated the poisoning of Ru sites. As a consequence, the Ru SAs-SnO2 /C exhibited a low overpotential at 10â mA cm-2 (10â mV) and a low Tafel slope of 25â mV dec-1 . This approach provides a new avenue to modulate the adsorption strength of active sites and intermediates, which paves the way for the development of highly active electrocatalysts.
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The search for economical, active and stable electrocatalysts towards the hydrogen evolution reaction (HER) is highly imperative for the progression of water electrolysis technology and related sustainable energy conversion technologies. The delicate optimization of chemical composition and architectural configuration is paramount to design high-efficiency non-precious metal HER electrocatalysts. Herein, we report a one-step scalable template/solvent-free pyrolysis approach for inâ situ immobilizing uniform CoP nanoparticles onto N and P co-doped carbon porous nanosheets (denoted as CoP@N,P-CNSs hereafter). The simultaneous consideration of architectural design and nanocarbon hybridization renders the formed CoP@N,P-CNSs with plentiful well-dispersed anchored active sites, shortened pathway for mass diffusion, enhanced electric conductivity, and reinforced mechanical stability. As a consequence, the optimized CoP@N,P-CNSs exhibit an overpotential of 115â mV to afford a current density of 10â mA cm-2 , small Tafel slope of 74.2â mV dec-1 , high Faradaic efficiency of nearly 100 %, and superb long-term durability in an alkaline medium. Given the fabrication feasibility, mass production potential and outstanding HER performance, the CoP@N,P-CNSs may hold great promise for large-scale electrochemical water splitting. More importantly, the explored one-step template/solvent-free pyrolysis methodology offers a feasible and versatile route to fabricate carbon nanosheet-based nanocomposites for diverse energy conversation-related applications.
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A Gram-stain-positive and motile bacterial strain, designated IB182363T, was isolated from surface seawater of the South China Sea. Cells grew at pH 5.0-9.5 (optimum, pH 7.0-8.0), 20-40 °C (optimum, 30 °C) and with 1-8â% (w/v) NaCl (optimum, 2-4â%). On the basis of 16S rRNA gene sequence analysis, strain IB182363T was affiliated to the genus Paenibacillus and the closest phylogenetically related species was Paenibacillus ginsengarvi DSM18677T with 96.9â% sequence similarity. The values of whole genome average nucleotide identity analysis and digital DNA-DNA hybridization between the isolate and the closely related type strains were less than 86.3 and 25.6â%, respectively. Chemotaxonomic analysis revealed that strain IB182363T possessed meso-diaminopimelic acid in the cell-wall peptidoglycan and contained menaquinone MK-7 as the predominant isoprenoid quinone. The major cellular fatty acids were anteiso-C15â:â0, C16â:â0 and iso-C16â:â0. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified glycolipid, two unidentified aminolipids, two unidentified phospholipids and four unidentified aminophospholipids. The genomic DNA G+C content was 54.5âmol%. On the basis of the above results, strain IB182363T represents a novel species of the genus Paenibacillus, for which we propose the name Paenibacillus oceani sp. nov. with the type strain IB182363T (=MCCC 1K04630T=JCM 34214T).
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Ácidos Graxos , Paenibacillus , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Paenibacillus/genética , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Água do Mar , Análise de Sequência de DNARESUMO
The alginate lyases have unique advantages in the preparation of alginate oligosaccharides and processing of brown algae. Herein, a gene alg2951 encoding a PL7 family alginate lyase with exo/endo-type activity was cloned from a novel marine bacterium Alteromonas portus HB161718T and then expressed in Escherichia coli. The recombinant Alg2951 in the culture supernatant reached the activity of 63.6 U/mL, with a molecular weight of approximate 60 kDa. Alg2951 exhibited the maximum activity at 25 °C and pH 8.0, was relatively stable at temperatures lower than 30 °C, and showed a special preference to poly-guluronic acid (polyG) as well. Both NaCl and KCl had the most promotion effect on the enzyme activity of Alg2951 at 0.2 M, increasing by 21.6 and 19.1 times, respectively. The TCL (Thin Layer Chromatography) and ESI-MS (Electrospray Ionization Mass Spectrometry) analyses suggested that Alg2951 could catalyze the hydrolysis of sodium alginate to produce monosaccharides and trisaccharides. Furthermore, the enzymatic hydrolysates displayed good antioxidant activity by assays of the scavenging abilities towards radicals (hydroxyl and ABTS+) and the reducing power. Due to its cold-adapted and dual exo/endo-type properties, Alg2951 can be a potential enzymatic tool for industrial production.
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Alteromonas/enzimologia , Antioxidantes/farmacologia , Polissacarídeo-Liases/isolamento & purificação , Alginatos/metabolismo , Antioxidantes/química , Antioxidantes/isolamento & purificação , Clonagem Molecular , Temperatura Baixa , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Peso Molecular , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/farmacologia , TemperaturaRESUMO
The brainstem, the core of the central nervous system, plays a vital role in controlling arterial blood pressure and its elevation of hypertension subtypes, especially essential hypertension. Integrative metabolic and proteomic profiling was performed on the brainstem samples of 11 week old spontaneously hypertensive rats (SHRs) and age-matched normotensive Wistar rats, using hydrophilic interaction liquid chromatography quadrupole/time-of-flight mass spectrometry (HILIC-Q/TOFMS) (PeptideAtlas: PASS01621) and nano-liquid chromatography-high-resolution-MS (nano-LC-high-resolution) combined with quantitative tandem mass tags (ProteomeXchange: PXD021210). The results showed a potentially significant measure of metabolic disorders in the brainstem of SHRs, including purine and pyrimidine metabolism and carnitine and acylcarnitine deficiency. By integrating the differential metabolites (VIP > 1 and p < 0.1) with the differentially expressed proteins (>1.2-fold and p < 0.05), the results revealed aberrant insulin signaling in the brainstem of SHRs, including reduced carnitine and acetylcarnitine; increased arginine; and increased flotillin-1 (FLOT1), hemoglobin subunit alpha-1/2, and hemoglobin subunit beta-2 proteins verified by the parallel reaction monitoring analysis (PeptideAtlas: PASS01622). The aberrant insulin signaling pathway in the brainstem of SHRs might help explain the correlation between essential hypertension and insulin resistance. These findings on the brainstem of SHRs could provide new insights into the dysregulation of the central nervous system in hypertension, especially as it relates to metabolite and protein levels.