Role of αENaC in root resorption of adjacent teeth due to entirely impacted mandibular third molars.

BACKGROUND: Entirely impacted mandibular third molar (EIM3M) concerns the pathological external root resorption (ERR) of the adjacent mandibular second molar (M2M) and formation of granulation tissue between two molars. The study aimed to clarify the effect of αENaC, a mechano-sensitive molecule, to explore the mechanical mechanism in this scenario. METHODS: The force EIM3M exerted on M2M was proved by finite element analysis. αENaC expressions were tested by real-time polymerase chain reaction (PCR), immunoblotting and immunofluorescence. Inflammatory and epithelial-mesenchymal transition (EMT)-related molecules expressions were also detected by real-time PCR. The correlation was analyzed by Spearman's correlation analysis, and receiver-operator characteristic (ROC) curve was further exhibited. RESULTS: The force was concentrated in the ERR area. αENaC was upregulated, positively correlated with ERR degree and localized to the fibroblasts in ERR granulation tissues. Moreover, αENaC was respectively and positively associated with elevated TNF-α and N-cadherin in ERR granulation tissues. More importantly, ROC analysis verified αENaC as a novel indication of the incidence of this disease. CONCLUSIONS: Our finding revealed the force from EIM3M causing ERR of M2M, and elucidated the expression and localization of αENaC and its positive correlation with inflammation, EMT and disease severity, suggesting a novel indication in this disease.

Effects of immediate loading directionality on the mechanical sensing protein PIEZO1 expression and early-stage healing process of peri-implant bone.

BACKGROUND: The reduced treatment time of dental implants with immediate loading protocol is an appealing solution for dentists and patients. However, there remains a significant risk of early peri-implant bone response following the placement of immediately loaded implants, and limited information is available regarding loading directions and the associated in vivo characteristics of peri-implant bone during the early stages. This study aimed to investigate the effects of immediate loading directionality on the expression of mechanical sensing protein PIEZO1 and the healing process of peri-implant bone in the early stage. METHODS: Thirty-two implants were inserted into the goat iliac crest models with 10 N static lateral immediate loading applied, followed by histological, histomorphological, immunohistochemical, X-ray microscopy and energy dispersive X-ray spectroscopy evaluations conducted after 10 days. RESULTS: From evaluations at the cellular, tissue, and organ levels, it was observed that the expression of mechanical sensing protein PIEZO1 in peri-implant bone was significantly higher in the compressive side compared to the tensile side. This finding coincided with trends observed in interfacial bone extracellular matrix (ECM) contact percentage, bone mass, and new bone formation. CONCLUSIONS: This study provides a novel insight into the immediate loading directionality as a potential influence factor for dental implant treatments by demonstrating differential effects on the mechanical sensing protein PIEZO1 expression and related early-stage healing processes of peri-implant bone. Immediate loading directions serve as potential therapeutic influence factors for peri-implant bone during its early healing stage.

Studying on Alloying Elements, Phases, Microstructure and Texture in FH36 Ship Plate Steel.

This study used simulation software and experiments to analyze the microstructure and texture of FH36 ship plate steel at different thicknesses and temperatures. The austenite phase transformed into ferrite phase at 830 °C and MC and M7C3 phases precipitated at 1150 °C and 543 °C, respectively. At room temperature, the microstructure at the surface and 1/4 thickness consisted of polygonal ferrite, acicular ferrite and granular bainite, while the 1/2 thickness had less acicular ferrite and granular bainite. The texture components were mainly {111}<110> and {111}<112> at all thicknesses, but {001}<110> was stronger at 1/2 thickness. The grain size decreased gradually from 1/2 thickness to the surface, and the proportion of high-angle grain boundaries was significantly lower at the surface than at 1/4 and 1/2 thickness.

Disulfide Bond Accelerated Transesterification in Poly(ß-hydrazide disulfide esters) toward Fast Network Rearrangements.

The development of catalyst-free ester-based covalent adaptable networks (CANs) provides a new approach to achieve milder reaction conditions to reprocess thermoset resins. Despite recent advances, however, accelerating network rearrangements requires the introduction of hydroxyl groups into the network. In this study, disulfide bonds are introduced into the CANs to add new kinetically facile pathways to accelerate network rearrangement. Kinetic experiments using small molecule models of the CANs show that the presence of the disulfide bonds can accelerate transesterification. These insights are applied to synthesize new kinds of poly(ß-hydrazide disulfide esters) (PSHEs) using thioctic acyl hydrazine (TAH) as a precursor for ring-opening polymerization with the hydroxyl-free multifunctional acrylates. The PSHE CANs have lower relaxation times (505-652 s) than the polymer containing only ß-hydrazide esters (2903 s). The ring-opening polymerization of TAH improves the crosslinking density, heating resistance deformation temperature, and UV shielding performance of the PSHEs. Thus, this work provides a practical strategy to reduce the reprocessing temperatures of CANs.

Profiling of bile acids and activated receptor S1PR2 in gingival tissues of periodontitis patients.

BACKGROUND: Bile acids, as a group of cholesterol metabolites, play important roles in inflammation and bone metabolism. However, the possible link between bile acids and periodontitis is still unclear. This study aimed to clarify the alterations of the bile acid profile and corresponding receptor expression levels in periodontitis patients, and evaluate their association with periodontitis severity. METHODS: The concentrations of 15 bile acids in gingival tissues from 16 periodontitis patients and 16 healthy individuals were tested by metabolomics. Sphingosine-1-phosphate receptor 2 (S1PR2) expression was determined by real-time PCR and immunohistochemistry, which was also validated in two datasets, GSE16134 and GSE10334. The correlation between bile acids, S1PR2, and clinical parameters was analyzed by Spearman's correlation analysis, and receiver-operator characteristic (ROC) curves were examined to access the ability of bile acids and S1PR2 for defining local periodontitis status. RESULTS: In the periodontitis group, concentrations of total bile acids were elevated by increases of all bile acid forms, and five conjugated bile acids were significantly increased. Meanwhile, the expression of their receptor, S1PR2, was also upregulated in the periodontitis group. Positive correlations were further observed between glycocholic acid (GCA), taurochenodeoxycholic acid (TCDCA), taurocholic acid (TCA), S1PR2, and periodontal clinical parameters. ROC analysis also showed combinations of two bile acids (GCA and TCDCA) with S1PR2 as novel signatures for indicating local periodontitis status. CONCLUSION: Our findings demonstrated the alterations of the bile acid profile and receptor S1PR2 expression in periodontitis patients, and provided evidence of association between bile acids and periodontitis status.

Upregulated Vanins and their potential contribution to periodontitis.

BACKGROUND: Although Vanins are closely related to neutrophil regulation and response to oxidative stress, and play essential roles in inflammatory diseases with clinical significance, their contribution to periodontitis remains to be determined. This research was designed to assess the expression of Vanins in human gingiva, and to define the relationship between Vanins and periodontitis. METHODS: Forty-eight patients with periodontitis and forty-two periodontal healthy individuals were enrolled for gingival tissue sample collection. Expression levels of VNN1, VNN2 and VNN3 were evaluated by RT-qPCR and validated in datasets GSE10334 and GSE16134. Western blot and immunohistochemistry identified specific proteins within gingiva. The histopathological changes in gingival sections were investigated using HE staining. Correlations between Vanins and clinical parameters, PD and CAL; between Vanins and inflammation, IL1B; and between Vanins and MPO in periodontitis were investigated by Spearman's correlation analysis respectively. Associations between VNN2 and indicators of neutrophil adherence and migration were further validated in two datasets. RESULTS: Vanins were at higher concentrations in diseased gingival tissues in both RT-qPCR and dataset analysis (p < 0.01). Assessment using western blot and immunohistochemistry presented significant upregulations of VNN1 and VNN2 in periodontitis (p < 0.05). The higher expression levels of Vanins, the larger the observed periodontal parameters PD and CAL (p < 0.05), and IL1B (p < 0.001). Moreover, positive correlations existed between VNN2 and MPO, and between VNN2 and neutrophil-related indicators. CONCLUSION: Our study demonstrated upregulation of Vanins in periodontitis and the potential contribution of VNN2 to periodontitis through neutrophils-related pathological processes.

4-Oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-d]pyrimidine Derivatives: Design, Synthesis, Insecticidal Assay and Binding Mode Studies.

A series of 4-oxo-4,5,6,7-tetrahydro-1H-pyrazolo[3,4-d]pyrimidine derivatives were designed and synthesized based on the fipronil low energy conformation by scaffold hopping strategy. Physicochemical properties calculation, insecticidal assay and binding mode studies were also performed. It was found that the target compounds displayed lower insecticidal activities than fipronil. The differences in binding modes between these compounds and fipronil may be the major reason for reduced insecticidal activities.

Study on the mode of action between Apis mellifera (α8)2(ß1)3 nAChR and typical neonicotinoids versus flupyradifurone with different bee-toxic levels.

The health of bee populations worldwide is affected by multiple factors, of which neonicotinoids are considered to be a main reason. Although most neonicotinoids are highly toxic to bees, some of them are relatively safe. To explore the molecular mechanism of these differences in toxicity, homology modelling, molecular docking and molecular dynamics simulations were applied to study the interactions between Apis mellifera (α8)2(ß1)3 nAChR and high bee-toxic neonicotinoid (imidacloprid, IMI), medium bee-toxic (thiacloprid, THI) and low bee-toxic butenolides (flupyradifurone, FPF). It was observed that three major interactions were similar across all systems, including water-bridge networks, π-π interactions and the polar interactions between the electron-withdrawing pharmacophores and the receptor. The calculated binding free energy was similar between IMI and THI. While FPF was the lowest bee-toxic, it displayed the strongest binding free energy value, the additional C-H⋯O H-bonds with Arg80 and Trp179 were the main reason. The bee toxicities of neonicotinoids and other nAChR modulators are not only determined by receptor affinities, but also by other factors (for example physicochemical properties and metabolic detoxification). All influencing factors should be fully considered in the future design of new eco-friendly insecticides that are safe for bees.

Hierarchical Co3O4@Ni3S2 electrode materials for energy storage and conversion.

Transition metal oxides are considered to be one of the most potential electrode materials. However, poor conductivity and insufficient active sites limit their actual applications. Rationally designed electrode materials with unique structural features can be ascribed to the efficient route for enhancing electrochemical performance. Here, we report hybrid Co3O4@Ni3S2 nanostructures obtained via a hydrothermal strategy and subsequent electrodeposition process. The obtained products can be used as electrodes for a hybrid supercapacitor with a specific capacity of 1071 C g-1 at 1 A g-1 and excellent rate capability. The as-assembled device delivers an energy density of 77.92 W h kg-1 at 2880 W kg-1. As an electrocatalyst, the above electrode possesses an overpotential of 237.6 mV at 50 mA cm-2 for oxygen evolution reaction.

Chromosome-Level Genome Assembly of the Green Peafowl (Pavo muticus).

The green peafowl (Pavo muticus) is facing a high risk of extinction due to the long-term and widespread threats of poaching and habitat conversion. Here, we present a high-quality chromosome-level genome assembly of the green peafowl with high contiguity and accuracy assembled by PacBio sequencing, DNBSEQ short-read sequencing, and Hi-C sequencing technologies. The final genome size was estimated to be 1.049 Gb, whereas 1.042 Gb of the genome was assigned to 27 pseudochromosomes. The scaffold N50 length was 75.5 Mb with a complete BUSCO score of 97.6%. We identified W and Z chromosomes and validated them by resequencing 14 additional individuals. Totally, 167.04 Mb repetitive elements were identified in the genome, accounting for 15.92% of the total genome size. We predicted 14,935 protein-coding genes, among which 14,931 genes were functionally annotated. This is the most comprehensive and complete de novo assembly of the Pavo genus, and it will serve as a valuable resource for future green peafowl ecology, evolution, and conservation studies.

Fatigue Crack Growth Behavior and Fracture Toughness of EH36 TMCP Steel.

The fatigue crack growth behavior and fracture toughness of EH36 thermo-mechanical control process (TMCP) steel were investigated by fatigue crack growth rate testing and fracture toughness testing at room temperature. Scanning electron microscopy was used to observe the fracture characteristics of fatigue crack propagation and fracture toughness. The results indicated that the microstructure of EH36 steel is composed of ferrite and pearlite with a small amount of texture. The Paris formula was obtained based on the experimental data, and the value of fracture toughness for EH36 steel was also calculated using the J-integral method. The observations conducted on fatigue fracture surfaces showed that there were a lot of striations, secondary cracks and tearing ridges in the fatigue crack propagation region. Additionally, there existed many dimples on the fracture surfaces of the fracture toughness specimens, which indicated that the crack was propagated through the mechanism of micro-void growth/coalescence. Based on the micromechanical model, the relationship between the micro-fracture surface morphology and the fracture toughness of EH36 steel was established.

Comparison of Microstructure and Mechanical Properties of High Strength and Toughness Ship Plate Steel.

E36 ship plate steel was, respectively, produced by as rolling and normalizing process (ARNP), and EH36 and FH36 ship plate steel was produced by the thermo-mechanical control process (TMCP) with low carbon and multi-element micro-alloying. The microstructure of the three grades of ship plate steel was composed of ferrite, pearlite, and carbides at room temperature. The average grain size on 1/4 width sections (i.e., longitudinal sections) of the three grades of ship plate steel was, respectively, 5.4 µm, 10.8 µm, and 11.9 µm. EH36 and FH36 ship plate steel had the higher strength due to precipitation and grain boundary strengthening effect, while the E36 ship plate steel had the lower strength due to the recovery phenomenon in the normalizing process. EH36 and FH36 ship plate steel had higher impact toughness due to lower carbon (C) and silicon (Si) content and higher manganese (Mn) content than E36 ship plate steel. E36 ship plate steel had the best plasticity due to the two strong {110} and {111} texture components. The fracture toughness KJ0.2BL(30) values of E36 and EH36 and KJ0.2BL value of FH36 ship plate steel were, respectively, obtained at 387 MPa·m1/2, 464 MPa·m1/2 and 443 MPa·m1/2. EH36 and FH36 ship plate steel had higher KJ0.2BL(30) due to lower C and Si and higher Mn, niobium (Nb), vanadium (V), and aluminum (Al) content than the E36 ship plate steel. The fatigue crack growth rate of E36 ship plate steel was higher than that of EH36 and FH36 ship plate steel due to its higher carbon content and obviously smaller grain size. The analysis results and data may provide a necessary experimental basis for quantitatively establishing the relationship between fracture toughness, yield strength and impact toughness, as well as the relationship between fatigue crack growth rate and both strength and fracture toughness.

Fabricating a Repairable, Recyclable, Imine-based Dynamic Covalent Thermosetting Resin with Excellent Water Resistance by Introducing Dynamic Covalent Oxime Bonds.

The sustainable production of adaptive, recyclable and imine-based dynamic covalent thermosetting resins (DCTRs) presents an opportunity for polymer scientists to address the prevalent environmental and energy concerns associated with current petroleum-based plastics. However, the imine-based DCTRs easily decompose in the presence of water, which can weaken the mechanical properties in imine-based polymers. In this study, we designed oxime-imine DCTRs that are stable in the presence of water and exhibit good mechanical properties. In the presence of one kind of amino group catalyst, the oxime-imine DCTRs could be completely recycled. Additionally, these well-designed oxime-imine DCTRs have good mechanical properties, high glass transition temperatures (166 °C), and good thermal stabilities. Taken together, this work offers a sustainable solution for the design and manufacture of high-value degradable materials intended for applications in which recyclability and reusability are indispensable.

Government environmental governance, structural adjustment and air quality: A quasi-natural experiment based on the Three-year Action Plan to Win the Blue Sky Defense War.

Improving air quality is an era task for China to transform its economic development model and enhance its environmental governance capabilities. This article take the Chinese government's Three-year Action Plan to Win the Blue Sky Defense War (abbreviated as the Blue Sky Defense War) as a quasi-natural experiment and use regression discontinuity design (RDD) to evaluate the governance effect of this policy. The study found that the Blue Sky Defense War reduced the monthly average concentration of PM2.5 and PM10 in cities by 14.49 and 23.43, respectively. Heterogeneity analysis shows that the Blue Sky Defence War has a more prominent effect on urban air quality management based on PM10 assessment; Jing-Jin-Ji region and surrounding areas are the key points to ensure the achievement of air management. Consistent and effective environmental governance policies, transparent and timely information disclosure and structural adjustment are all powerful guarantees for the effectiveness of the Blue Sky Defense War. These research conclusions provide new ideas for developing countries to formulate practical environmental pollution control policies.

Effect of mechanical combined with electromagnetic stirring on the dispersity of carbon fibers in the aluminum matrix.

In order to improve the uneven distribution of carbon fibers (CFs) in the matrix by traditional single mechanical stirring, mechanical combined with electromagnetic (M-E) stirring was used to prepare short carbon fibers reinforced aluminum matrix (Csf/Al) composites. The 3-D flow field of aluminum melt under mechanical/M-E stirring were calculated and compared. The calculation results show that the complexity of flow field under M-E stirring could be significantly enhanced relative to a single mechanical stirring, especially there was a strong melt flow near the crucible wall due to the skin effect. It was found that except the inertial force under mechanical stirring and the melt collision with the crucible walls, CFs were also subjected to the electromagnetic force and the oscillating flow between the eddy currents, which would promote the dispersity of the short CFs in the composites. The experimental results are consistent with the calculation results. The experimental results show that the distribution of CFs at each position in the composite samples prepared under M-E stirring was stable. The uniform distribution of CFs in the composites would play an important role in improving the overall performance of the Csf/Al composites.

Insights into pesticide toxicity against aquatic organism: QSTR models on Daphnia Magna.

The toxicities of agrochemicals to non-target aquatic organisms are key items in chemical ecological risk assessment. However, it is still an urgent need to develop new tools to assess the agrochemical aquatic toxicity efficiently and accurately. In this work, QSTR studies were performed on a data set containing 639 diverse pesticides with measured EC50 toxicity against Daphnia magna, by using five machine learning methods combined with seven fingerprints and a set of molecular descriptors. The imbalance problem of the data set was successfully solved by clustering analysis. The top-10 QSTR models displayed greater predicative abilities than ECOSAR. The optimal model, Ext-SVM, showed the best performance in 10-fold cross validation (Qhigh=0.807, Qmoderate=0.806, Qlow=0.755, Qtotal=0.794), and also in the test set verification (Qhigh=0.865, Qmoderate=0.783, Qlow=0.931, Qtotal=0.848). The relevance of the key physical-chemical properties with the toxicity was also investigated, in which the MW, a_np, logP(o/w), GCUT_SLOGP_1, chilv and SMR_VSA7 values displayed positive correlation with Daphnia magna toxicity, whereas the logS and a_don showed negative correlation. The robust QSTR models provided efficient tools for assessing agrochemical aquatic toxicity, and the revealed different physical-chemical properties between the high and low toxic compounds might be useful in the discovery and design of low aquatic toxic pesticides.

Architectural Design of 3D Printed Scaffolds Controls the Volume and Functionality of Newly Formed Bone.

The successful regeneration of functional bone tissue in critical-size defects remains a significant clinical challenge. To address this challenge, synthetic bone scaffolds are widely developed, but remarkably few are translated to the clinic due to poor performance in vivo. Here, it is demonstrated how architectural design of 3D printed scaffolds can improve in vivo outcomes. Ceramic scaffolds with different pore sizes and permeabilities, but with similar porosity and interconnectivity, are implanted in rabbit calvaria for 12 weeks, and then the explants are harvested for microcomputed tomography evaluation of the volume and functionality of newly formed bone. The results indicate that scaffold pores should be larger than 390 µm with an upper limit of 590 µm to enhance bone formation. It is also demonstrated that a bimodal pore topology-alternating large and small pores-enhances the volume and functionality of new bone substantially. Moreover, bone formation results indicate that stiffness of new bone is highly influenced by the scaffold's permeability in the direction concerned. This study demonstrates that manipulating pore size and permeability in a 3D printed scaffold architecture provides a useful strategy for enhancing bone regeneration outcomes.

Simultaneous Surface Modification and Chemical Reduction of Graphene Oxide Using Glucose.

In this paper, we develop a simple and facile approach to prepare graphene nanosheets through chemical reduction with glucose as reducing agent and modification agent. The reduced and modified graphene by glucose (denoted as g-rGO) was characterized with techniques of Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Raman spectra, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), etc. It is found that, besides the desired reduction capability to graphene oxide (denoted as GO), glucose plays an important role as a modifying reagent in stabilizing the as-prepared graphene nanosheets simultaneously and the g-rGO exhibits good dispersibility and stability in water and waterborne polyurethane matrix (denoted as WPU). Moreover, the g-rGO can improve evidently the mechanical properties, weather ability and water resistance of WPU.

3D Printing of Lotus Root-Like Biomimetic Materials for Cell Delivery and Tissue Regeneration.

Biomimetic materials have drawn more and more attention in recent years. Regeneration of large bone defects is still a major clinical challenge. In addition, vascularization plays an important role in the process of large bone regeneration and microchannel structure can induce endothelial cells to form rudimentary vasculature. In recent years, 3D printing scaffolds are major materials for large bone defect repair. However, these traditional 3D scaffolds have low porosity and nonchannel structure, which impede angiogenesis and osteogenesis. In this study, inspired by the microstructure of natural plant lotus root, biomimetic materials with lotus root-like structures are successfully prepared via a modified 3D printing strategy. Compared with traditional 3D materials, these biomimetic materials can significantly improve in vitro cell attachment and proliferation as well as promote in vivo osteogenesis, indicating potential application for cell delivery and bone regeneration.