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The materials currently used for bone prostheses are mainly metals such as titanium alloy. Compared with human cortical bone, traditional metals exhibit high elastic moduli, which may lead to stress shielding. In contrast, the mechanical strength and elastic modulus of polyetheretherketone are slightly lower than those of human bone. In this study, we utilize multi-component co-modification in order to improve the mechanical properties of polyetheretherketone materials. Firstly, we blended three types of materials: multi-walled carbon nanotubes, nanohydroxyapatite, and carbon fibers. Then, the blended materials were used to reinforce polyetheretherketone, and the preparation of the multi-walled carbon nanotubes/nanohydroxyapatite/carbon fibers was described in detail. After the contact angle was determined, SEM, thermogravimetric analysis, and various tests were conducted on the ternary composites. Ball milling co-mingling technology was used to prepare tetrad composite specimens for tensile and compression experiments, a finite element model of the tetrad composite tensile and compression specimens was established, and the structural stresses of the specimens were analyzed under the specified loads. The experimental results show that the surface roughness of carbon fiber increased, and the multi-walled carbon nanotube/nanohydroxyapatite/carbon fiber/polyetheretherketone quaternary composites were well optimized in terms of strength and elastic modulus, which broadens the application field of polyetheretherketone materials. [ABSTRACT FROM AUTHOR]

Porous structures can reduce the elastic modulus of implants, decrease stress shielding, and avoid bone loss in the alveolar bone and aseptic loosening of implants; however, there is a mismatch between yield strength and elastic modulus as well as biocompatibility problems. This study aimed to investigate the parametric design method of porous root-shaped implants to reduce the stress-shielding effect and improve the biocompatibility and long-term stability and effectiveness of the implants. Firstly, the porous structure part was parametrically designed, and the control of porosity gradient distribution was achieved by using the fitting relationship between porosity and bias and the position function of bias. In addition, the optimal distribution law of the porous structure was explored through mechanical and hydrodynamic analyses of the porous structure. Finally, the biomechanical properties were verified using simulated implant–bone tissue interface micromotion values. The results showed that the effects of marginal and central porosity on yield strength were linear, with the elastic modulus decreasing from 18.9 to 10.1 GPa in the range of 20–35% for marginal porosity, with a maximum decrease of 46.6%; the changes in the central porosity had a more consistent effect on the elastic modulus, ranging from 18.9 to 15.3 GPa in the range of 50–90%, with a maximum downward shift of 19%. The central porosity had a more significant effect on permeability, ranging from 1.9 × 10−7 m2 to 4.9 × 10−7 m2 with a maximum enhancement of 61.2%. The analysis showed that the edge structure had a more substantial impact on the mechanical properties. The central structure could increase the permeability more effectively. Hence, the porous structure with reasonable gradient distribution had a better match between mechanical properties and flow properties. The simulated implantation results showed that the porous implant with proper porosity gradient distribution had better biomechanical properties. [ABSTRACT FROM AUTHOR]

To address the issues of insufficient strength and poor precision in polystyrene forming parts during the selective laser sintering process, a ternary composite of polystyrene/glass fiber/hollow glass microbeads was prepared through co-modification by incorporating glass fiber and hollow glass microbeads into polystyrene using a mechanical mixing method. The bending strength and dimensional accuracy of the sintered composites were investigated by conducting an orthogonal test and analysis of variance to study the effects of laser power, scanning speed, scanning spacing, and delamination thickness. The process parameters were optimized and selected to determine the optimal combination. The results demonstrated that when considering bending strength and Z-dimensional accuracy as evaluation criteria for terpolymer sintered parts, the optimum process parameters are as follows: laser power of 24 W, scanning speed of 1600 mm/s, scanning spacing of 0.24 mm, and delamination thickness of 0.22 mm. Under these optimal process parameters, the bending strength of sintered parts reaches 6.12 MPa with a relative error in the Z-dimension of only 0.87%. The bending strength of pure polystyrene sintered parts is enhanced by 15.69% under the same conditions, while the relative error in the Z-dimension is reduced by 63.45%. It improves the forming strength and precision of polystyrene in the selective laser sintering process and achieves the effect of enhancement and modification, which provides a reference and a new direction for exploring polystyrene-based high-performance composites and expands the application scope of selective laser sintering technology. [ABSTRACT FROM AUTHOR]

Enterotoxigenic Escherichia coli (ETEC) causes severe diarrhea in piglets. The current primary approach for ETEC prevention and control relies on antibiotics, as few effective vaccines are available. Consequently, an urgent clinical demand exists for developing an effective vaccine to combat this disease. Here, we utilized food-grade Lactococcus lactis NZ3900 and expression plasmid pNZ8149 as live vectors, together with the secreted expression peptide Usp45 and the cell wall non-covalent linking motif LysM, to effectively present the mutant LTA subunit, the LTB subunit of heat-labile enterotoxin, and the FaeG of F4 pilus on the surface of recombinant lactic acid bacteria (LAB). Combining three recombinant LAB as a live vector oral vaccine, we assessed its efficacy in preventing F4+ ETEC infection. The results demonstrate that oral immunization conferred effective protection against F4+ ETEC infection in mice and piglets lacking maternal antibodies during weaning. Sow immunization during late pregnancy generated significantly elevated antibodies in colostrum, which protected piglets against F4+ ETEC infection during lactation. Moreover, booster immunization on piglets during lactation significantly enhanced their resistance to F4+ ETEC infection during the weaning stage. This study highlights the efficacy of an oral LAB vaccine in preventing F4+ ETEC infection in piglets by combining the sow immunization and booster immunization of piglets, providing a promising vaccination strategy for future prevention and control of ETEC-induced diarrhea in piglets. [ABSTRACT FROM AUTHOR]

Background Agenesis of third molar agenesis has a higher incidence than other tooth development anomalies. Previous research identified a potential correlation between third molar agenesis and specific craniofacial morphology; however, no systematic review and meta-analysis on this topic currently exists. Objective The objective of this systematic review and meta-analysis was to evaluate the association between third molar agenesis and craniofacial sagittal and vertical morphology. Search methods An electronic search was conducted on PubMed, Embase, Web of Science, and the Cochrane Library without restrictions on publication year or language; this was supplemented by the manual retrieval of relevant literature. Selection criteria Cross-sectional studies that compared craniofacial morphology using angular and linear measurements obtained from lateral cephalography between patients with third molar agenesis and those without were included. Data collection and analysis The quality assessment of the enrolled articles was evaluated by the Joanna Briggs Institute critical appraisal tool. Meta-analysis and sensitivity analysis were performed by Review Manager software (The Cochrane Collaborative, version 5.4, Cochrane IMS). Results A total of seven studies were included. Meta-analysis demonstrated that the ANB (mean differences (MD) = –0.75, 95% CI: –1.31 to –0.19, P < 0.01), palate length (ANS–PNS, MD = –1.68, 95% CI: –2.24 to –1.11, P < 0.01), and mandibular length (Go-Pog, MD = –0.36, 95% CI: –0.59 to –0.13, P < 0.01) were smaller in patients with third molar agenesis. With regard to vertical craniofacial morphology, the mandibular plane angle (MP-FH; MD = –1.88, 95% CI: –3.45 to –0.31, P = 0.02), gonial angle (gonial angle; MD = –1.73, 95% CI: –2.69 to –0.77, P < 0.01) and lower face height (lower face heigh angle; MD = –1.36, 95% CI: –1.94 to –0.77, P < 0.01) were smaller in patients with third molar agenesis, indicating a flatter or brachyfacial skeletal pattern. Conclusions The results of this study suggest that third molar agenesis maybe associated with a reduced maxillary length and a flatter mandible. However, these findings need to be interpreted with caution due to inconsistencies in the certainty of evidence. Clinical Trial Registration PROSPERO (CRD42023448226). [ABSTRACT FROM AUTHOR]

This study examines the effect of the lateral bone cut end (LBCE) on the pattern of lingual split during bilateral sagittal split osteotomy (BSSO) in patients with skeletal class III malocclusion. A case-control study according to the pattern of the sagittal split osteotomy (SSO) lingual split line was conducted in patients who underwent BSSO. The primary predictor variable was the ratio of the LBCE. The primary outcome variable was the type of lingual fracture line classified according to the lingual split scale (LSS). Other variables included patients' weight, sex, age, left and right sides of the mandible, and experience of the surgeon. Logistic regression analysis or the chi-squared test was performed to determine the effect of these variables on various types of lingual fracture line. The significance level was 95% (p < 0.05). There were 271 patients enrolled in this study. The SSO lingual split lines were divided into LSS1 (329/542), LSS2 (82/542), LSS3 (93/542), and LSS4 (38/542) splits. Logistic regression analysis showed that the LSS3 split was more likely to appear when the LBCE was closer to the lingual side (p = 0.0017). The age of patients significantly affected the possibilities of LSS2 (p = 0.0008) and LSS3 (p = 0.0023) splits. A LBCE close to the lingual side was an inducer for the formation of a LSS3 split in patients with skeletal class III malocclusion during BSSO. The age of the patient also affected the possibility of LSS2 and LSS3 splits. [ABSTRACT FROM AUTHOR]

It is well known that CsCl‐type FeRh undergoes from antiferromagnetic (AFM) to ferromagnetic (FM) phase transition near room temperature with large thermal hysteresis. Therefore, it is particularly essential to find new methods to manipulate the magnetic order of FeRh and reduce thermal hysteresis. Herein, the magnetic phase transition of FeRh film by applying a low‐frequency in‐plane alternating current (AC) magnetic field is successfully manipulated. It is found that under the AC magnetic field, the phase transition of the FM–AFM is promoted, and the heating branch shifts at a rate of −8 K T−1, which causes the thermal hysteresis of FeRh reduction of about 2 K. These phenomena may be attributed to the Zeeman energy and the periodic vibration of domain walls. This work provides the possibility for the realization of low‐power spintronic devices. [ABSTRACT FROM AUTHOR]

One of the most prominent characteristics of bisphosphonate-related osteonecrosis of the jaw(BRONJ) is its site-specificity. Osteonecrosis tends to occur specifically in maxillofacial bones, in spite of a systemic administration of the medicine. Previous studies suggested rich blood supply and fast bone turnover might be reasons for BRONJ. Yet, a sound scientific basis explaining its occurrence is still lacking. The present study aimed to explore the role of Porphyromonas gingivalis (P. gingivalis), an important oral pathogen, on the site-specificity of bisphosphonate-induced osteonecrosis and to elucidate its underlying mechanism. Mice were intraperitoneally injected with zoledronic acid (ZA) or saline for 3 weeks. In the third week, the right mandibular first molars were extracted and circular bone defects with a diameter of 1 mm were created in right femurs. After the operation, drug administration was continued, and P. gingivalis suspension was applied to the oral cavities and femur defects. The mice were killed after four or eight weeks postoperatively. The right mandibles and femurs were harvested for micro-CT and histological analyses. A poor healing of bone defects of both jaws and femurs was noted in mice injected with both ZA and P. gingivalis. Micro-CT analysis showed a decreased bone volume, and histological staining showed an increased number of empty osteocyte lacunae, a decreased collagen regeneration, an increased inflammatory infiltration and a decreased number of osteoclasts. In addition, the left femurs were collected for isolation of osteoclast precursors (OCPs). The osteoclastogenesis potential of OCPs was analyzed in vitro. OCPs extracted from mice of ZA-treated groups were shown to have a lower osteoclast differentiation potential and the expression level of related genes and proteins was declined. In conclusion, we established a mouse model of bisphosphonate-related osteonecrosis of both the jaw and femur. P. gingivalis could inhibit the healing of femur defects under the administration of ZA. These findings suggest that P. gingivalis in the oral cavity might be one of the steering compounds for BRONJ to occur. [ABSTRACT FROM AUTHOR]

Zero-valent iron (ZVI), with high reduction capacity and cost effectiveness, has been widely used as an activator for persulfate in remediation of organic pollutants. However, the existence of inherent iron oxide shell blocked the transfer of proton and further reduced its reactivity. In present study, a novel persulfate (PS) activator BZVI@OA was synthesized via ball milling ZVI with oxalic acid dihydrate. Scanning electron microscope, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectrometry and Time-of-flight secondary ion mass spectroscopy confirmed the original low proton conductive oxidation shell was replaced by a high proton conductive FeC 2 O 4 shell. The generated shell significantly improved persulfate activated capacity, through which degradation rates of various contaminants were enhanced for 1.64 to 2.33 times. Dissolved oxalate was proved to form complexes with iron ions, dramatically reduced the potential difference and relieved the blocked cyclic conversion. Electron paramagnetic resonance and quenching experiments confirmed an inner sphere adsorption of PS on FeC 2 O 4 ·2H 2 O shell which facilitated the peroxide bonds cleavage, leading high efficiency of ROS generation. The accelerated proton transition was confirmed with AC impedance method, resulting in fast and elevated surface bound Fe2+ for persulfate decomposition into active species. Furthermore, BZVI@OA/PS system demonstrated high tolerance over wide initial pH range and promising reusability within 6 cycles. This work clarifies an effective strategy for developing efficient modified ZVI as a PS activator for organic pollutant degradation in water. [Display omitted] • FeC 2 O 4 ·2H 2 O shell replaced the passive oxide layer through ball milled ZVI with H 2 C 2 O 4 ·2H 2 O. • Oxalic acid-modified ZVI established effective activate persulfate ability to degradation various organic pollutants. • FeC 2 O 4 ·2H 2 O shell provided inner ball adsorption with persulfate. • FeC 2 O 4 ·2H 2 O shell enhanced proton conductive and accelerated the core corrosion. • C 2 O 4 2−·promoted iron cycling by reducing the redox potential between Fe2+ and Fe3+. [ABSTRACT FROM AUTHOR]

Mercury (Hg2+) contamination in water is associated with potential toxicity to human health and ecosystems. Many research studies have been ongoing to develop new materials for the remediation of Hg2+ pollution in water. In this study, a novel thiol- and amino-containing fibrous adsorbent was prepared by grafting 2-amino-5-mercapto-1,3,4-thiadiazol (AMTD) onto PAN fiber through a microwave-assisted method. The synthesized functional fiber was characterized by FTIR, SEM, and elemental analysis. Adsorption tests depicted that for mercury uptake, PAN MW -AMTD fiber exhibited enhanced adsorption capacity compared with other fibrous adsorbents and selective adsorption feature under the interference of other metal ions, including Pb2+, Cu2+, Cd2+, and Zn2+. The influence of pH on the adsorption process was investigated and the effect of temperature revealed that the adsorption sorption process was endothermic and the adsorption performance of PAN MW -AMTD was elevated with the increase of temperature. Kinetic studies of PAN MW -AMTD fiber followed the pseudo-second-order and the adsorption isotherm of Hg2+ was well fitted by Sips and Langmuir equations, given the maximum adsorption amount of 332.9 mg/g. XPS results suggested that a synergetic coordination effect of sulfur and nitrogen in functional fiber with mercury took responsibility for the adsorption mechanism in the uptake process. In addition, the prepared PAN MW -AMTD fiber could easily be regenerated with 0.1 M HCl for five times without significant reduction of mercury removal efficiency. Thus, this study will facilitate the research on novel functional material for the removal of mercury from water. • An AMTD-modified PAN fiber was efficiently prepared with MW-assisted method. • PAN MW -AMTD fiber displays excellent removal efficiency and selective ability for Hg2+. • Maximum adsorption capacity of PAN MW -AMTD fiber for mercury was obtained at 332.9 mg/g. • Adsorption mechanism is chemisorption and N and S coordinated with Hg2+. • PAN MW -AMTD fiber remained as a cost-effective and reusable chelating adsorbent. [ABSTRACT FROM AUTHOR]