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As a new type of functional and structural material, the porous metal materials have been widely used in the fields of sound absorption, energy absorption, fluid distribution, heat exchange, catalysis, filtration, and separation, which are the most widely used in the field of filtration and separation. Porous metal materials can achieve the liquid−solid and gas−solid filtration separation for the different fluids in the fields of petroleum and petrochemical, fine chemical, coal chemical, and other fields, and the requirements for the materials and mechanical properties of the porous metal materials used in the different fields are also different. The preparation process of porous metal materials used for filtration is relatively mature, but there is little investigation on the corrosion resistance and mechanical properties of the porous metal materials, which will directly affect the use effect and life of such materials. The research progress on the mechanical properties and corrosion resistance of the porous metal materials used for filtration in recent years was briefly reviewed in this paper, and the existing problems in the corrosion and mechanical behavior of such materials were discussed. Finally, the research direction of the porous metal materials used for filtration was prospected.

The fundamental biological characteristics of tumor cells are characterized by irregularities in signaling and metabolic pathways, which are evident through increased glucose uptake, altered mitochondrial function, and the ability to evade growth signals. Interventions such as fasting or fasting-mimicking diets represent a promising strategy that can elicit distinct responses in normal cells compared to tumor cells. These dietary strategies can alter the circulating levels of various hormones and metabolites, including blood glucose, insulin, glucagon, growth hormone, insulin-like growth factor, glucocorticoids, and epinephrine, thereby potentially exerting an anticancer effect. Additionally, elevated levels of insulin-like growth factor-binding proteins and ketone bodies may increase tumor cells' dependence on their own metabolites, ultimately leading to their apoptosis. The combination of fasting or fasting-mimicking diets with radiotherapy or chemotherapeutic agents has demonstrated enhanced anticancer efficacy. This paper aims to classify fasting, elucidate the mechanisms that underlie its effects, assess its impact on various cancer types, and discuss its clinical applications. We will underscore the differential effects of fasting on normal and cancer cells, the mechanisms responsible for these effects, and the imperative for clinical implementation. [ABSTRACT FROM AUTHOR]

In response to the practical production challenges posed by the unreliable operation of the V-shaped squeezing soil-covering and -pressing device (VCP) for planters under clay soil conditions in Northeast China, incomplete seed furrow closure, and severe soil adhesion on pressing wheels, this study proposes a device with star-toothed concave discs for soil-covering and -pressing (STCP) with the aim of enhancing the soil-covering quality of planters. The main working principles of STCP were expounded, and its main structural and installation parameters were determined and designed. Based on bionics, with the dung beetle's protruding head structure as the research object and UHMWPE as the material, an optimized protuberance-type bionic pressing wheel was designed. A Box–Behnken experiment was conducted by taking the width of the compression wheel, the spring deformation, and the installation angle as experimental factors, as well as the weight of the soil adhered to the surface of the pressing wheel (SW) and the soil compactness (SC) as the evaluation indicators. The optimal structural parameters of the pressing device were determined as follows: the width of the pressing wheel was 60.57 mm, the spring deformation was 55.19 mm, and the installation angle was 10.70°. The field comparison tests of soil covering performance showed that the star-tooth concave disc soil-covering device can effectively solve the problem of seed "hanging" and "drying". The average covered soil weight of the star-tooth concave disc soil-covering device was 241.46 g, and the average covered soil weight of VCP was 223.56 g. Compared with VCP, the average covered soil weight of STCP increased by 8.01%. The variation coefficient of covered soil weight after the operation of the star-tooth concave disc soil-covering device was 3.71%, which was more uniform than VCP. The field comparison tests of soil-covering thickness showed that the uniformity of soil-covering thickness can be significantly improved by adding a star-tooth concave disc soil-covering device to VCP. The comparative tests of soil anti-adhesive showed that the convex hull type pressing wheels optimized by bionics had better soil anti-adhesive performance, and the soil adhesion weight was reduced by 43.68% compared with VCP. The field comparative tests of seedling emergence showed that the seedling emergence rate after STCP operation was 3.9% higher than that of VCP. [ABSTRACT FROM AUTHOR]

In order to elucidate the impact of pressurized tubes' structures on the sowing performance of pneumatic seed delivery systems, the EDEM–CFD coupled simulation method was employed to analyze the influence of pressurized tube parameters, including length (L), corrugation depth (S), corrugation width (K), and the number of corrugations, on seed movement characteristics, distribution uniformity, and airflow patterns. Simulation-validated experiments were conducted to study the impact of the optimal pressurized tube structure on seeding performance. The results indicate that pressurized tubes significantly enhance the uniformity coefficient of seed distribution, reduce seed velocity, and decrease the coefficient of variation in distribution uniformity. When pressurized tube parameters, specifically length (L), corrugation depth (S), corrugation width (K), and the number of corrugations, are set at 800 mm, 8 mm, 50 mm, and 6, respectively, the uniformity coefficient of seed distribution exceeds 95%, and the coefficient of variation in seed discharge consistency for each row is less than 3.2%. Moreover, the seed velocity at the outlet of the pressurized tube, the relative velocity of two-phase flow, and pressure loss are all minimal, indicating superior seeding performance. This research provides valuable insights into the analysis of seed movement characteristics within pressurized tubes and the optimization of their structural parameters. [ABSTRACT FROM AUTHOR]

Objective To explore the role of apoliprotein D (APOD) in the proliferation and migration of human dental pulp cells (DPCs) and to provide a basis for the use of APOD to promote pulp regeneration. Methods APOD ex⁃ pression in human dental pulp cells was inhibited by siRNA. The inhibition effect of APOD was confirmed by qPCR and Western blot. After APOD inhibition, colony formation experiments and CCK8 assays were employed to confirm the proliferation ability of dental pulp cells. Transwell assays were used to verify the cell migration ability after the inhibi⁃ tion of APOD expression. Results After inhibiting APOD expression, the colony formation rate in the si⁃apod group was reduced compared with the NC group, and the difference was statistically significant (t＝7.624, P＝0.002). The CCK8 experiment showed that the OD value in the si⁃apod group decreased at 3, 5 and 7 d compared with that in the NC group (P < 0.05). Transwell results showed that the number of cell divisions was 57.25 ± 4.03 in the si⁃apod group and 154.50 ± 8.39 in the NC group, and the difference was statistically significant (t＝10.45, P < 0.001). Conclusion Inhibition of APOD expression in dental pulp cells inhibits their proliferation and migration ability.

Objective To analyze the morphology and incidence of middle mesial canal (MM) and isthmus in the mandibular first permanent molar by cone⁃beam computed tomography (CBCT). Methods Statistical analysis was per⁃ formed on images from patients who underwent CBCT examination in the Department of Radiology at Stomatological Hospital, Southern Medical University. Samples exhibiting root canal treatment, root resorption and calcification were ex⁃ cluded. Data regarding sex, age, the presence or absence of isthmus and MM, and the number of roots and root canals were recorded. Results Of the 217 mandibular first molar samples, 8 (3.7%) had an MM, and 2 (0.9%) had an inde⁃ pendent apical foramen. The overall incidence rate of isthmus was 57.1%; this rate was 50.7% in the cervical third of the root canal, 17.5% in the middle third, and 13.4% in the apical third. The incidence rate of isthmus was 61.8% on the left side, 52.3% on the right side, 58.7% in males, and 55.8% in females. No significant difference was found be⁃ tween the left and right sides or between females and males (P > 0.05). The incidence rate of isthmus in people under 60 was greater than 50% but was significantly lower in people older than 60. Conclusion Only a very small propor⁃ tion of MMs have an independent apical foramen in the mandibular first molar. The incidence of isthmus in the mesial root of the mandibular first permanent molar is high, and isthmus usually occurs in the cervical third of the root canal. During root canal treatment or apical surgery, attention should be given to the physical and chemical preparation of the isthmus.

Objective: Degenerative thoracolumbar hyperkyphosis (DTH) is a disease that negatively affects individual health and requires surgical intervention, yet the ideal surgical approach and complications, especially distal junctional failures (DJF), remain poorly understood. This study aims to investigate DJF in DTH and to identify the risk factors for DJF so that we can improve surgical decision‐making, and advance our knowledge in the field of spinal surgery to enhance patient outcomes. Methods: This study retrospectively reviewed 78 cases (late osteoporotic vertebral compression fracture [OVCF], 51; Scheuermann's kyphosis [SK], 17; and degenerative disc diseases [DDD], 10) who underwent corrective surgery in our institute from 2008 to 2019. Clinical outcomes were assessed using health‐related quality of life (HRQOL) measures, including the visual analogue scale (VAS) scores for back and leg pain, the Oswestry disability index (ODI), and the Japanese Orthopaedic Association (JOA) scoring system. Multiple radiographic parameters, such as global kyphosis (GK) and thoracolumbar kyphosis (TLK), were assessed to determine radiographic outcomes. Multivariate logistic regression analysis was employed to identify the risk factors associated with DJF. Results: HRQOL improved, and GK, TLK decreased at the final follow‐up, with a correction rate of 67.7% and 68.5%, respectively. DJF was found in 13 of 78 cases (16.7%), two cases had wedging in the disc (L3‐4) below the instrumentation, one case had a fracture of the lowest instrumented vertebrae (LIV), one case had osteoporotic fracture below the fixation, nine cases had pull‐out or loosening of the screws at the LIV and three cases (23.1%) required revision surgery. The DJF group had older age, lower computed tomography Hounsfield unit (CT HU), longer follow‐up, more blood loss, greater preoperative sagittal vertical axis (SVA), and poorer postoperative JOA and VAS scores (back). The change in TLK level was larger in the non‐DJF group. Post‐sagittal stable vertebrae (SSV) moved cranially compared with pre‐SSV. Conclusion: Age, CT HU, length of follow‐up, estimated blood loss, and preoperative SVA were independent risk factors for DJF. We recommend fixation of the two vertebrae below the apex vertebrae for DTH to minimize surgical trauma. [ABSTRACT FROM AUTHOR]

Objective Explore the role and status of tumor necrosis factor receptor⁃associated factor 6 (TRAF6) in the inflammatory response of human osteoblast⁃like cells MG63 which was triggered by Enterococcus faecalis (E. faeca⁃ lis) and its lipoteichoic acid (LTA). Methods SiRNA technology was applied to silence the TRAF6 gene of MG63 cells, Using E.faecelis and its LTA to stimulate the silence MG63 cells with different hours. After that, using real⁃time PCR technology to detect toll⁃like receptor 2 (TLR2) and TRAF6 gene expression and using ELISA assay to detect pro⁃ inflammatory cytokines interleukin⁃1β and TNF⁃alpha expression levels. Results When MG63 cells was infected by E. faecalis, its LTA, TLR2 and TRAF6 gene level has increased to varying degrees (P < 0.05); interleukin⁃1β and TNF⁃ alpha expression was significantly higher (P < 0.05). When TRAF6 gene of MG63 cells was silenced by siRNA, pro⁃in⁃ flammatory cytokines interleukin ⁃ 1β, interleukin ⁃6, interleukin ⁃8 and TNF ⁃alpha expression decreased significantly (P < 0.05). Conclusion E. faecalis and its toxic components is identified by MG63 cells mainly through TLR2 recep⁃ tors. The major virulence factor in periapical infections caused by E. faecalis is LTA.