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Rechargeable aqueous zinc-manganese oxide batteries have attracted extensive attention in energy-storage systems owing to their high safety and low cost but still suffer from the lack of advanced cathode materials with both high capacity and a long cycle life. Here, the bismuth-doped α-MnO2 was synthesized by a hydrothermal method. The preintercalation of Bi3+ effectively enlarges the lattice spacing and boosts the electrochemical performance of Zn/MnO2 batteries. The systematical studies suggest that Bi doping significantly optimized the electrochemical behavior and especially enhanced the reversibility of dissolution-deposition and phase transition processes. As a result, the Bi-doped α-MnO2 cathode achieves a superior performance high reversible specific capacity (325 mA h g-1 at 300 mA g-1) and long cycling stability (90.9% capacity retention after 2000 cycles at 1000 mA g-1). By comparison with the α-MnO2 electrode, the Bi-doped α-MnO2 electrode exhibits a longer and stabler discharge plateau. It is different from most anionic doping methods, which attribute the performance improvement to superior ion diffusion kinetics and enhanced structural stability. Therefore, this work offers a new viewpoint and approach to improve the electrochemical property of Zn/MnO2 batteries.Parkinson's disease is a chronic and progressive neurodegenerative disease, induced by slow and progressive death of the dopaminergic (DA) neurons from the midbrain region called substantia nigra (SNc) leading to difficulty in locomotion. At present, very few potential therapeutic drugs are available for treatment, necessitating an urgent need for development. In the current study, the parkin transgenic Drosophila melanogaster model that induces selective loss in dopaminergic neurons and impairment of locomotory functions has been used to see the effect of the aza-flavanone molecule. D. melanogaster serves as an amazing in vivo model making valuable contribution in the development of promising treatment strategies. Our in-silico study showed spontaneous binding of this molecule to the D2 receptor making it a potential dopamine agonist. PARKIN protein is well conserved, and it has been reported that Drosophila PARKIN is 42% identical to human PARKIN. Interestingly, this molecule enhances the motor coordination and survivability rate of the transgenic flies along with an increase in expression of the master regulator of Dopamine synthesis, that is, tyrosine hydroxylase (TH), in the substantia nigra region of the fly brain. Moreover, it plays a significant effect on mitochondrial health and biogenesis via modulation of a conserved mitochondrial protein PHB2. Therefore, this molecule could lead to the development of an effective therapeutic approach for the treatment of PD.A unique supramolecular approach of preparing and using a cucurbit[8]uril (Q[8])-based dynamic host-guest assembly for cyanide sensing in and removal from water has been successfully developed. The dicyanovinyl-attached cationic guest (1) was designed as the fluorescent response moiety for the detection of the cyanide anion via a nucleophilic addition reaction in the assist of the Q[8]-based 22 quaternary complexes. Furthermore, the reaction of cyanide with 1 further switched the Q[8]-based host-guest assemblies from the 22 complexes to the 11 supramolecular polymers that precipitate in water. Thus, the macrocyclic-based dynamic host-guest assembly has potential use in applications for solving the problem of toxic anion pollutants present in aqueous environments.We report the identification of the ter gene cluster responsible for the formation of the p-terphenyl derivatives terfestatins B and C and echoside B from the Appalachian Streptomyces strain RM-5-8. We characterize the function of TerB/C, catalysts that work together as a dual enzyme system in the biosynthesis of natural terphenyls. TerB acts as a reductase and TerC as a dehydratase to enable the conversion of polyporic acid to a terphenyl triol intermediate. X-ray crystallography of the apo and substrate-bound forms for both enzymes provides additional mechanistic insights. Validation of the TerC structural model via mutagenesis highlights a critical role of arginine 143 and aspartate 173 in catalysis. Cumulatively, this work highlights a set of enzymes acting in harmony to control and direct reactive intermediates and advances fundamental understanding of the previously unresolved early steps in terphenyl biosynthesis.Potassium-ion batteries (PIBs) as a new electrochemical energy storage system have been considered as a desirable candidate in the post-lithium-ion battery era. Nevertheless, the study on this realm is in its infancy; it is urgent to develop electrode materials with high electrochemical performance and low cost. Iron sulfides as anode materials have aroused wide attention by virtue of their merits of high theoretical capacities, environmental benignity, and cost competitiveness. Herein, we constructed carbon-free crystal-like Fe1-xS and demonstrated its feasibility as a PIB anode. The unique structural feature endows the prepared Fe1-xS with plentiful active sites for electrochemical reactions and short transmission pathways for ions/electrons. The Fe1-xS electrode retained capacities of 420.8 mAh g-1 after 100 cycles at 0.1 A g-1 and 212.9 mAh g-1 after 250 cycles at 1.0 A g-1. Even at a high rate of 5.0 A g-1, an average capacity of 167.6 mAh g-1 was achieved. In addition, a potassium-ion full cell is assembled by employing Fe1-xS as an anode and potassium Prussian blue as a cathode; it delivered a discharge capacity of 127.6 mAh g-1 at 100 mA g-1 after 50 cycles.Longevity is a near-universal human aspiration that can affect moral progress and economic development at the social level. In rapidly developing China, questions about the geographical distribution and environmental factors of longevity phenomenon need to be answered more clearly. This study calculated the longevity index (LI), longevity index for females (LIF) and longevity index for males (LIM) based on the percentage of the long-lived population among the total number of elderly people to investigate regional and gender characteristics at the county level in China. A new multi-scale geographically weighted regression (MGWR) model and four possible geographical environmental factors were applied to explore environmental effects. The results indicate that the LIs of 2838 counties ranged from 1.3% to 16.3%, and the distribution showed obvious regional and gender differences. In general, the LI was high in the East and low in the West, and the LIF was higher than the LIM in 2614 counties (92.1%). The MGWR model performed well explaining that geographical environmental factors, including topographic features, vegetation conditions, human social activity and air pollution factors have a variable influence on longevity at different spatial scales and in different regions. These findings enrich our understanding of the spatial distribution, gender differences and geographical environmental effects on longevity in China, which provides an important reference for people interested in the variations in the associations between different geographical factors.The organoid is a kind of distinctive micro-organ formed by stem cells with the ability of self-renewal, which can be cultured in three-dimensional scaffold in vitro. With the development of cell culture system, organoids have been gradually applied in researches such as in vitro organ model establishment, drug testing and even the repairing or replacing damage organs. It shows significantly promising prospects. This review article aims to summarize the latest research progress and provide the theoretical foundation and prospects for the development of organoids in stomatology.Both pathological injuries and clinical iatrogenic operations can lead to dentin demineralization, forming demineralized dentin matrix (DDM). Dentin demineralization activates endogenous matrix metalloproteinase (MMP) and cysteine cathepsin (CC), and the mechanical properties of DDM decrease, so DDM is prone to lose its structural integrity under the action of enzymatic degradation and mechanical destruction, which in turn results in the reduction of clinical functional value of DDM in dentin-resin bonding restoration. The administrations of dentin collagen cross-linking reagents and MMP/CC inhibitors are effective strategies to protect DDM structural integrity and achieve its clinical functional value. A variety of chemically synthesized reagents and plant-derived extracts are capable of significantly improving the mechanical properties of DDM and enhancing its enzymatic tolerance. However, the cytotoxicity caused by chemically synthesized reagents and the tooth staining aroused by plant extracts have considerably affected their clinical applicability. Protecting dentin collagen while exerting antibacterial properties is a new direction for future DDM protective agent research. Accordingly, from the perspectives of cross-linking reagents, enzyme inhibitors and compounds which possess the dual proper ties, this review discusses the latest research progress in DDM protection, and looks into its application prospects in dentin-resin bonding, in an attempt to provide reference for the clinical promotion of DDM protection strategy.Metabolic syndrome is a cluster of metabolic abnormalities including abdominal obesity, insulin resistance, hypertension and atherogenic dyslipidemia and is associated with increased risk of cardiovascular disease and diabetes. Periodontitis is a chronic inflammatory disease caused by plaque biofilm, which shares risk factors with the major noncommunicable diseases such as heart disease, diabetes and chronic respiratory disease. Many cross-sectional studies have investigated the link between periodontal disease and metabolic syndrome showing that the odds of periodontitis increase with the number of metabolic syndrome components present in an individual although the causal relationship between them has not been determined yet. In this paper, the research progress on the relationship and mechanism of periodontitis with the main characteristics of metabolic syndrome are presented in order to provide new evidences for the prevention and intervention of metabolic syndrome and periodontitis.The standardized training of specialist doctors is an important part of medical education after graduation and it is the only way to train clinicians to diagnose and treat the specialist diseases independently by using a standardized and high-quality way. The prevalence of periodontal disease and the proportion of patienets with severe and advanced periodontitis in our country are high and the diagnosis and treatment process for the periodontal disease are complicated. There is an urgent need to expand the team of periodontal specialists capable of the specialized treatment. The training of periodontal specialists in our country has just started. The present article summarizes the exploration and practice of periodontal specialist training in Peking University School and Hospital of Stomatology in the past five years, including the establishment of training bases, formulation of clear training goals, strict implementation of training rules, strengthening of process quality control to ensure the trainees could reach the expected standard of periodontal specialist after training.