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Existing optimization research on the crankshaft heat treatment process is mostly based on one-sided considerations, and less consideration is given to the matching of multiple process parameters, leading to irrational designs of heat treatment. To address this problem, this work investigates the influence mechanisms of cooling speed, tempering temperature, and holding time on the performance evaluation indexes of the straightness, residual stress, and martensite content of a crankshaft based on the response surface method. The results showed that the order of influence of these three different process parameters on the performance evaluation index was cooling speed > holding time > tempering temperature, and the order of influence on the performance evaluation indexes under multifactorial process parameters was cooling speed–holding time > cooling speed–tempering temperature > holding time–tempering temperature. The optimal process parameters were a cooling speed of 1.4 times the cooling oil, a tempering temperature of 555 °C, and a holding time of 6 h, with the straightness of the crankshaft reduced by 9.9%, the surface stress increased by 6.7%, and the martensitic content increased by 7.2% after the process optimization. This work can provide new clues for optimizing the heat treatment process parameters of crankshafts. [ABSTRACT FROM AUTHOR]

Recently, the studies of topological corner states (TCSs) have been extended from crystals to quasicrystals, which are referred to as higher‐order topological quasicrystalline insulators (HOTQIs). However, the TCSs of complete quasi‐periodic structure in photonic systems have yet to be demonstrated. Moreover, there is only one TCS in each corner region in higher‐order topological insulators (HOTIs). Increasing the number of TCS is expected to increase the application potential of TCSs. In this work, HOTQIs in photonic systems are experimentally observed. It is found that HOTQIs possess TCS arrays, and each TCS array contains several TCSs. Furthermore, the universal theoretical framework of the multimer analysis method is improved, and the difference in the average charge density is proposed as a real‐space topological index. These results will open up new ideas for investigating highly integrated, multi‐region localized TCSs and are expected to provide new ways to explore topological phenomena and the applications of photonic quasicrystals. [ABSTRACT FROM AUTHOR]

This paper focuses on the study of the induction heating process of a camshaft in a marine diesel engine. A three-dimensional finite element model for dynamic induction heating is established using the finite element method of multi-physical field coupling, aiming to investigate the temperature uniformity of the cam during this process. Three elements are analyzed in this study: the moving speed, the gap between the induction coil and the workpiece, and the width of the induction coil. These factors allow for an analysis of the temperature distribution in the thickness direction and contour line direction of the cam under various conditions. On this basis, an equivalent parameter about the temperature uniformity in the thickness direction of the cam is proposed to guide the selection of the camshaft induction heating process parameters. [ABSTRACT FROM AUTHOR]

Mechanical components often experience fatigue loading from various waveform conditions during their operational lifespan. However, the underlying mechanisms through which variations in loading waveform affect the fatigue life of components remain unclear. Thus, this study conducted tension–compression fatigue experiments on 34CrNi3MoVA steel specimens under the same stress amplitude with different waveforms (cosine, triangular, sawtooth, and reverse sawtooth) to investigate the effects of loading waveform variations on the cyclic strain hardening behaviors, the fatigue fracture failure, and the fatigue life. The results indicated that specimens under different waveforms all exhibited cyclic strain hardening. The fatigue cyclic hardening level progressively increased in the order of cosine, triangular, and sawtooth waveforms, resulting in a continuous increase in cyclic saturation strain amplitude. The analysis of fatigue fractures demonstrated a consistent increase in both the initiation and propagation zone areas in the order of cosine, triangular, and sawtooth waveforms, and the boundary between the propagation and final fracture zones gradually shifted from a straight to a curved shape. The influence mechanisms of cyclic loading waveforms on the fatigue life of specimens were analyzed based on the energy dissipation, leading to the development of a universal fatigue life prediction model applicable to different waveform conditions, the model was then verified with the reverse sawtooth wave specimens and resulted in a prediction error less than 15%. The study is expected to serve as a significant guide for predicting and evaluating the fatigue life of mechanical components under various fatigue loading conditions. [ABSTRACT FROM AUTHOR]

The generation of grinding cracks during the grinding process will adversely affect the service performance of the workpiece and even cause the workpiece to be scrapped. However, the microscopic formation mechanism of grinding cracks is still unclear at present. In this regard, the morphologies of grinding cracks on the surface of the cam were characterized, and the initiation and propagation behaviors of grinding cracks were analyzed from the perspectives of element composition, micro-structure and surface work hardening. Based on the experimental results and analysis, the generation mechanism of grinding cracks is clarified, and measures to prevent the grinding cracks are proposed. [ABSTRACT FROM AUTHOR]

By substituting Equation (4) into Equation (3), one can get 5 HT ht Generally, I i SB f sb ' equals the true fracture strength of specimens approximately,5 so, the 1/2-( I i SB b sb / I i SB f sb ') SP 1/ I b i sp is defined as a constant of I B i . [Extracted from the article]

The velocity head and momentum exchange at the T-junction between the surge tank with a riser and the tail water tunnel of hydroelectric powerplants have been introduced by using the Gardel's head-loss formula. The effects of the velocity head and momentum exchange on the critical sectional area of the downstream tank have been analyzed. With Thoma's assumption, the critical stable sectional area of the downstream throttled surge tank is derived theoretically. The study shows that the velocity head has an unfavorable effect on water level stability in the downstream surge tank while the effect of the momentum exchange is positive. These two effects counteract. Thus, the critical sectional area of a downstream throttled surge tank is close to that of a corresponding simple surge tank. However, if the size and shape of a riser are optimized, the area of the downstream surge tank may be further reduced. It is also demonstrated that a downstream throttled surge tank can reduce electricity loss and easily meet the requirements of stability in large flow oscillations when compared to a simple downstream tank. CE Database subject headings: Hydroelectric powerplants; Tanks; Velocity head; Head loss; Moment distribution.

Background: This study compared the in vitro erosive effects of 2 western and 2 Chinese medicinal over-the-counter paediatric medications on primary teeth in a continuous time scale., Methods: Twenty enamel blocks obtained from 10 deciduous incisors were randomly assigned into 5 groups (n = 4 each): Group GA and Group GB-paracetamol liquid (Jean-Marie Pharmacal Co. Ltd and Universal Pharmaceutical Laboratories Ltd, respectively); Group GC and Group GD-reconstituted Chinese medicinal granules (Huarun 999 and Guizhou Bailing Group Pharmaceutical Co. Ltd, respectively); and deionised water (control group). The pH levels of these liquids were assessed. The immersion process was repeated for 20 rounds. For each round, each sample was immersed in liquid for 15 seconds and then rinsed with deionised water for 15 seconds. Mean hardness ratio (MHR) at 5, 10, 15, and 20 rounds was evaluated using Vickers microhardness test. The initial and final surface morphology and chemistries were analysed by scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS)., Results: All 4 liquid medications have shown acidic pH (4.74-5.76). After 20 rounds of immersion, the MHR 20 of the GA (0.886) and GB (0.930) groups decreased significantly from the original MH 0 . The GC (0.978) and GD (0.985) groups illustrated a similar trend as the deionised water control group (0.985). Despite EDS, chemical analysis showed an increase of Ca/C mole ratio after drug immersion, and no significant difference (P > .05) was found on the ratios Ca/P and Ca/C and the amounts of magnesium or sodium before and after immersion according to the Wilcoxon signed-rank analysis. Distinctive enamel loss with irregular craters, and a corroded surface with fracture lines along the border of prism head were observed in the SEM of groups GA and GB, respectively. However, findings in both Chinese medicine groups were similar, such that erosive changes were barely seen, similar to the control group., Conclusions: This study concluded that the pH of liquid medication may not be a significant factor that contributes to enamel softening. Traditional Chinese granule medications may be a safer option for primary teeth., Competing Interests: Conflict of interest None disclosed., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Oral squamous cell carcinoma (OSCC) is a common human malignancy. However, its pathogenesis and prognostic information are poorly elucidated. In the present study, we aimed to probe the most significant differentially expressed genes (DEGs) and their prognostic performance in OSCC. Multiple microarray datasets from the Gene Expression Omnibus (GEO) database were aggregated to identify DEGs between OSCC tissue and control tissue. Least absolute shrinkage and selection operator (LASSO) Cox model was constructed to determine the prognostic performance of the aggregated DEGs based on The Cancer Genome Atlas (TCGA) OSCC cohort. Ten datasets with 341 OSCC samples and 283 control samples were included. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment revealed that the integrated DEGs were enriched in the IL-17 signaling pathway, viral protein interactions with cytokines and cytokine receptors, and amoebiasis, among others. Our LASSO Cox model was able to discriminate two groups with different overall survival in the training cohort and test cohort (p < 0.001). The time-dependent receiver operating characteristic (ROC) curve revealed that the area under the curve (AUC) values at one year, three years, and five years were 0.831, 0.898, and 0.887, respectively. In the testing cohort, the time-dependent ROC curve showed that the AUC values at one year, three years, and five years were 0.696, 0.693, and 0.860, respectively. Our study showed that the integrated DEGs of OSCC might be applicable in the evaluation of prognosis in OSCC. However, further research should be performed to validate our findings.

Qu-Zhuo-Tong-Bi ( QZTB ) is an empirical traditional Chinese medicine prescription for treating acute gouty arthritis clinically without serious adverse effects in mainland China. However, the biochemical mechanism underlying the therapeutic action produced by QZTB treatment against acute gouty arthritis and the effect on recurrent attack remain unknown. In this study, we investigated the anti-inflammatory and analgesic effects of QZTB on acute gouty arthritis and the recurrent attack in rats, as well as the underlying mechanisms. The gouty arthritis model was established by intra-articular injection of monosodium urate (MSU) crystal suspension (2 mg/50  μ L) into the right ankle joint of Sprague Dawley (SD) male rats. QZTB (500 mg/kg) and the positive control drug meloxicam were administrated by gavages twice a day for 7 days before, or 3 days after, first MSU injection in different experiments, respectively. The analgesic effects were evaluated by pain-like behaviors and hind paw mechanical withdrawal threshold testing. The anti-inflammatory activities were evaluated by ankle swelling measurement, histologic examination, NLRP3 inflammasome, and inflammatory cytokine expression. Western blot and quantitative real-time PCR were used to detect the protein and mRNA expressions of NLRP3. IL-1 β and TNF- α level in the blood serum were detected by enzyme-linked immunosorbent assay (ELISA). QZTB can suppress ankle swelling and synovial inflammation in the MSU-induced gouty arthritis rat model. QZTB alleviated the acute attack and prevented the recurrent attack of gouty arthritis. In addition, QZTB treatment significantly decreased both mRNA and protein levels of NLRP3, as well as the production of IL-1 and TNF- α in the ankle joint of model rats. Taken together, these results suggest that QZTB may be a promising herbal formula for the prevention and treatment of gouty arthritis in humans., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2019 Huiqing Lv et al.)

Colorectal anastomosis remains a key aspect in mid- and lower-rectal surgery, particularly in patients who are male, obese, status post neoadjuvant chemoradiation, or possess narrow pelvic anatomy. Transanal total mesorectal excision (taTME) and transabdominal total mesorectal excision (TME) both primarily allow position of the tumor to dictate whether circular stapling or hand-sewing is utilized to achieve anastomosis. Given that taTME only requires a single circular stapler to achieve anastomosis, it consequently decreases the risk of jeopardizing blood supply to the anastomotic site. Should transanal hand-sewing be pursued, numerous points in performing the purse-string suture warrant particular attention: (1) Before suturing, separate the distal rectum to be anastomosed from the surrounding tissues, and ensure the full-layer suture of the distal purse-stitched suture. (2) It is recommended that beginners complete the suturing process under direct visualization without removing the transanal platform. (3) Commonly used anastomosis designs include end-to-end, side-to-end, J-pouch, or coloplasty, depending on patient characteristics and surgeon preferences. Our single-institution clinical experience suggests that taTME patients who underwent neoadjuvant chemoradiation or transanal hand-sewn anastomosis should still have a temporary colostomy created. To date, literature has yet to demonstrate the superiority of taTME anastomosis outcomes. This publication aims to point out anastomosis techniques and safety pointers, as well as clinical experiences.

Notoginsenoside R1 (NGR1), one of the main effective components of Panax notoginseng, appears to be effective in promoting osteogenesis and treating osteoporosis. However, hitherto, whether NGR1 can directly promote osteoblastogenesis remains to be elucidated. In the present study, we hereby examined the effects of NGR1 on the osteoblastogenesis of a pre-osteoblast cell line (MC3T3-E1) in in vitro time-course and dose-dependent experiments. Its efficacy was evaluated by assessing cell viability (indicator of proliferation), alkaline phosphatase (ALP) activity (a marker of early osteoblastic differentiation), levels of osteocalcin (OCN; a marker of late osteoblastic differentiation), calcium deposition (a marker of final mineralization) and the expression of a series of osteoblastogenic marker genes (such as collagen Iα, Runx2, ALP and OCN) at different time points. When examining the proliferation of and ALP activity in the pre-osteoblasts, a bell-shaped dose-response pattern was observed when the cells were treated with various concentrations of NGR1, with a peak being observed at the concentration of 50 µg/ml. NGR1 markedly increased the expression of OCN at the concentration of 1,000 µg/ml in a dose‑dependent manner. Furthermore, treatment with 1,000 µg/ml NGR1 resulted in the highest mineralization by 4.3- and 5.9-fold on the 21st and 28th day, respectively compared with the control group (no treatment). On the whole, our findings indicate that NGR1 significantly promotes the osteoblastogenesis of pre-osteoblasts, which suggests that NGR1 has potential for use as a bone regeneration agent.

A porous hydroxylapatite-containing titania film was prepared by an electrochemical oxidation method, i.e. micro-arc oxidation (MAO). During the oxidation treatment, the titanium sample was immersed in electrolytic solution containing calcium acetate monohydrate and sodium biphosphate dihydrate by using a pulse power supply. The thickness, phase, composition and morphology of the oxide coating were monitored with X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive X-ray spectrometer (EDS). The thickness of the MAO film is about 20 microm and the coating where each porous size is no more than 5 microm was porous and uneven, without apparent interface to the titanium substrates. The coating formed in the Ca- and P-containing solution with MAO contained Ca and P along with Ti and O. The Ca/P ratio on the surface is 1.63, while that in the interface is 0.51. XRD showed that the porous coating was made up of anatase, rutile and hydroxyapatite. Such MAO films are expected to have significant medical applications as dental implants and artificial bone joints.