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Objective: This study analyzed and compared the biomechanical properties of maxillary sinus floor mucosa with implants at three different maxillary sinus angles during a modified internal sinus floor elevation procedure. Methods: 3D reconstruction of the implant, maxillary sinus bone, and membrane were performed. The maxillary sinus model was set at three different angles. Two internal maxillary sinus elevation models were established, and finite element analysis was used to simulate the modified maxillary sinus elevation process. The implant was elevated to 10 mm at three maxillary sinus angles when the maxillary sinus floor membrane was separated by 0 and 4 mm. The stress of the maxillary sinus floor membrane was analyzed and compared. Results: When the maxillary sinus floor membrane was separated by 0 mm and elevated to 10 mm, the peak stress values of the implant on the maxillary sinus floor membrane at three different angles were as follows: maxillary sinus I: 5.14–78.32 MPa; maxillary sinus II: 2.81–73.89 MPa; and maxillary sinus III: 2.82–51.87 MPa. When the maxillary sinus floor membrane was separated by 4 mm and elevated to 10 mm, the corresponding values were as follows: maxillary sinus I: 0.50–7.25 MPa; maxillary sinus II: 0.81–16.55 MPa; and maxillary sinus III: 0.49–22.74 MPa. Conclusion: The risk of sinus floor membrane rupture is greatly reduced after adequate dissection of the maxillary sinus floor membrane when performing modified internal sinus elevation in a narrow maxillary sinus. In a wide maxillary sinus, the risk of rupture or perforation of the wider maxillary sinus floor is reduced, regardless of whether traditional or modified internal sinus elevation is performed at the same height. [ABSTRACT FROM AUTHOR]

As a typical difficult-to-machine material, the strong wear resistance and high hardness of carbon fiber in carbon fiber–reinforced plastics (CFRPs) lead to rapid tool wear during the cutting process, exacerbating surface damage of the hole and significantly increasing production costs. The investigation of tool wear has always been the pivotal focus in low-cost manufacturing. However, no similar work has been reported yet in tool wear of CFRP helical milling To fill this gap, this paper aims to conduct a theoretical analysis of the tool wear mechanism in helical milling of CFRPs and summarize the trends in tool wear under different cutting amounts as well as the impact of tool wear on cutting force and hole quality. Tool wear characteristics in terms of helical milling were studied carefully. Discussions on the tool wear morphology, cutting parameters, cutting force, and hole wall roughness were also provided. The findings in this paper might offer guidance on tool wear mechanisms for extending tool life and increasing hole-making quality in helical milling of CFRPs. [ABSTRACT FROM AUTHOR]

Drilling-induced burr and delamination are the main defects in carbon fiber–reinforced polymers (CFRPs). Although substantial CFRP defect measurement methods have been suggested, it is still challenging to recognize and measure the defects due to the drilling-induced chips, non-drilling-induced material reflections, and textured surface of CFRPs. To this end, the main purpose of the present paper is to develop a method able to recognize and measure the drilling-induced burr and delamination in CFRPs based on two techniques of bimodal threshold segmentation method and K-means clustering. To implement these techniques, images are captured by the image capturing setup with specific illumination. And the proposed defect measurement method is validated through full factorial drilling experiments in CFRP workpieces and compared with manual measurement supported by conventional image processing method. The results of the comparative measurement on the proposed method and manual method show that there is a reasonable agreement between them. Moreover, the proposed method can separate burr and delamination from regions of chips and textured surface of CFRPs. Considering the efficient, automated, and repeatable nature of the proposed method, it is anticipated to provide a meaningful reference for recognizing and measuring drilling-induced defects in the presence of strong interfering targets. [ABSTRACT FROM AUTHOR]

Renal fibrosis is the common final pathway in many renal diseases regardless of the underlying etiology. Adipocyte enhancer-binding protein 1 (AEBP1) was reported to play a vital role in the development of organ fibrosis, but its role in renal fibrosis has not been reported. Thus, the aim of this study was to investigate the possible function of AEBP1 in renal fibrosis and the mechanism associated with the β-catenin signaling pathway. A total of 83 genes upregulated after unilateral ureteral obstruction (UUO) were screened from two Gene Expression Omnibus (GEO) datasets and subjected to Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Among them, AEBP1 was enriched in collagen binding and the regulation of collagen fibril organization and was confirmed to be upregulated in UUO kidneys and TGF-β1-induced cells. Knockdown of AEBP1 ameliorated renal fibrosis via reducing collagen accumulation, inhibiting epithelial–mesenchymal transition and fibroblast transformation, as evidenced by decreases in the expression of collagen I and III, Col1a1, Col3a1, fibronectin, Snail, α-SMA, as well as collagen-specific staining of kidney tissues, whereas the E-cadherin was increased. Besides, AEBP1 silencing inhibited the expression of β-catenin in nucleus and β-catenin downstream proteins (Axin2, Myc, and Ccnd1). Continuously active β-catenin–S33Y further restored the inhibitory effect of AEBP1 silencing on renal fibrosis. These findings indicate that knockdown of AEBP1 could potentially slow down renal fibrosis by blocking the β-catenin signaling pathway, highlighting the potential of AEBP1 as a therapeutic target for renal fibrosis. [ABSTRACT FROM AUTHOR]

Electrochemical water oxidation enables the conversion of H2O to H2O2. It holds distinct advantages to the O2 reduction reaction, which is restricted by the inefficient mass transfer and limited solubility of O2 in aqueous media. Nonetheless, most reported anodes suffer from high overpotentials (usually >1000 mV) and low selectivity. Electrolysis at high overpotentials often causes serious decomposition of peroxides and leads to declined selectivity. Herein, we report a ZnGa2O4 anode with dual active sites to improve the selectivity and resist the decomposition of peroxides. Its faradaic efficiency reaches 82% at 2.3 V versus RHE for H2O2 generation through both direct (via OH−) and indirect (via HCO3−) pathways. The percarbonate is the critical species generated through the conversion of bicarbonate at Ga-Ga dual sites. The peroxy bond is stable on the surface of the ZnGa2O4 anode, significantly improving faradaic efficiency. Developing efficient anodes for H2O2 production via water oxidation remains challenging. Here, the authors report a ZnGa2O4 anode with dual active sites to improve the selectivity and to resist the decomposition of H2O2, and the peak faradaic efficiency reaches 82% at a low potential. [ABSTRACT FROM AUTHOR]

In this paper, the author discusses the deformations of compact complex manifolds with ample canonical bundles. It is known that a complex manifold has unobstructed deformations when it has a trivial canonical bundle or an ample anti-canonical bundle. When the complex manifold has an ample canonical bundle, the author can prove that this manifold also has unobstructed deformations under an extra condition. [ABSTRACT FROM AUTHOR]

We collected solonchaks samples of 5 subtypes and 13 genera from Gansu Province in China and analyzed the diversity of fungal communities with the methods of ITS sequencing. We found that ACE, Chao 1, Simpson and Shannon indices of the fungal community varied significantly in soil samples and were generally inversely correlated with pH. The dominant fungal groups were Ascomycota and Basidiomycota among the different solonchaks. Redundancy analysis revealed that soil organic matters was the most important driving force for fungal composition (29.9%), and the second most influencing factor was sulfate ion (9.1%). Our results suggest that Ascomycota was the main indicator phylum reflecting changes of the microbial groups and soil organic matter as a key factor drove the composition of fungal community in 5 subtypes and 13 genera of solonchaks in Gansu Province. [ABSTRACT FROM AUTHOR]

Tool condition is highly relative to the productivity, quality, and safety of ultrasonic vibration-assisted drilling (UVAD) of carbon fiber-reinforced polymer (CFRP). Tool breakage can cause the degradation of drilling quality and maybe even lead to unexpected machine downtime. Therefore, tool breakage monitoring is the key technique of ensuring drilling quality and realizing fully automated drilling. However, existing tool breakage monitoring methods based on machine learning need training model previously, which is impractical for the actual drilling process. In this work, a novel tool breakage monitoring method based on a sequential probability ratio test (SPRT) in UVAD of CFRP is proposed. Three different damage levels are introduced to simulate the tool breakage in the drilling process. The vibration signals collected under different tool damage levels in the experiment are preprocessed by low-pass filtering to remove the disturbance frequency generated by the ultrasonic spindle system. To reduce data redundancy, the signals are downsampled according to the useful frequency band and the feature parameter extracted from test signals is finally fed into the SPRT model as a test sequence to recognize tool damage levels. Root mean square error (RMSE) between the same conditions and between different types of conditions was selected as the criteria to evaluate the reliability of the method. The test results and error analysis show that the method is effective and reliable to classify different tool breakage conditions during UVAD of CFRP. [ABSTRACT FROM AUTHOR]

Bacterial myocarditis is a key cause leading to myocardial damage and cardiac dysfunction. Mesencephalic astrocyte-derived neurotrophic factor (MANF) has been found to be an anti-inflammatory factor. This study is to explore the effect of MANF on LPS-induced myocardial inflammation and macrophage differentiation. The myocarditis mouse model was constructed by LPS treatment. Myocardial damage and serum inflammatory factors were evaluated by ELISA. RT-qPCR was used to detect mRNA of M1/M2 macrophage markers. Western blot, immunohistochemical, and immunofluorescent staining were used to examine myocardial M1/M2 macrophages and NF-κB activation. Mono-macrophage-derived MANF deficiency enhanced LPS-induced inflammatory response and increased M1 macrophages in myocardium tissues, further causing more severe myocardial injury and lower survival rate of mice. Also, LPS-induced myocardial NF-κB activation was strengthened after mono-macrophage-derived MANF knockout. Mono-macrophage-derived MANF inhibits bacterial myocarditis and myocardial M1 macrophage differentiation, which is potential to be used for bacterial myocarditis treatment clinically. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced polymers (CFRPs) are becoming increasingly prevalent in the industries including automobile, aerospace, and military due to their light quality, high specific strength, high corrosion resistance, excellent thermodynamics performance, etc. However, these excellent properties easily result in intensive tool wear, short tool life, and reduced machining accuracy. Although ultrasonic vibration–assisted drilling (UVAD) was considered an effective drilling method to reduce tool wear, most reported studies focused on machining kinematics or mechanics, and very few studies systematically explored the tool wear behaviors in UVAD of CFRP. To fill this gap, this paper aims to investigate tool wear of high-speed steel (HSS) twist drill in UVAD of CFRP and compares these wear behaviors with those in conventional drilling based on the experimental observation of the worn drill morphologies. The effects of cutting parameters on tool wear were discussed with the special focus on the differences in tool wear between conventional drilling (CD) and UVAD. The observed wear behaviors can include abrasion, adhesion, oxidization, or the combination of them. The introduction of UVAD can effectively reduce the average width of tool flank wear with a maximum reduction of 13.0% when compared with CD. Both increased feed rate and decreased spindle speed can lead to decreased tool wear. The findings in this paper might offer guidance on the selection of cutting parameters for extending tool life in UVAD of CFRP. [ABSTRACT FROM AUTHOR]

Nanofiltration (NF) membranes show great potential for advanced water treatment, especially for trace organic pollutant removal. The removal efficiency of pharmaceuticals and personal care products (PPCPs) and environmental estrogenic hormones (EEHs) by positively charged hollow fiber NF membranes (PEI-NF) were evaluated. The separation properties were evaluated by changing the operating pressure, temperature, ionic strength, and cation species. A relationship between the physicochemical characteristics of the pharmaceuticals and the NF membrane retention behavior was established. The results showed that the rejection rates of the PEI-NF membrane for the selected PPCPs and EEHs ranged from 81 to ~ 91.26%. For positively (negatively) charged pharmaceutical molecules, the electrostatic repulsion (attraction) effect and steric hindrance were the dominant rejection mechanisms of the PEI-NF membrane. For neutral pharmaceutical molecules, in addition to the size sieving effect, the hydration-induced size increase of hydrophilic substances improved the rejection rates. Both the molecular structure and diffusion coefficient of pharmaceutical molecules influenced their rejection by the PEI-NF membrane to a certain extent. Moreover, the PEI-NF membrane showed a high removal effect for PPCPs and EEHs in water samples from actual tap water plants. [ABSTRACT FROM AUTHOR]