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In many circumstances, the conventional ultrasonic liquid-level detection presents the unreliable estimations due to the dynamically changed liquid level. In addition, there are circumstances where the level change involves not only the fluctuation but also the rise or fall of liquid level. To improve the measuring accuracy of liquid level using the ultrasonic method in dynamically changed level case, an attractive ultrasonic method, named the liquid-level detection based on the multiple-input multiple-output ultrasonic transducer array, is proposed in this paper. This method is different from the early ultrasonic liquid-level detections, including those that utilize transducer array. Based on the virtual element technology, the method employs the multitransducer array to achieve the reduction of system complexity and cost, and then applies the synthetic aperture technology to realize rapid samples of liquid level. Besides, one adaptive searching scheme of focused position in beamforming of synthetic aperture in each scanning direction is optimized to get the high precise samples of liquid level. The proposed method is verified by simulation and a real system, and compared with the conventional single-channel approach. We still proposed a simulation method of ultrasonic echo signal from liquid level based on the boundary-layer theory and the ultrasonic scattering theory. The simulated and actual measurement results demonstrate that the proposed method is obviously superior to the conventional approach. Meanwhile, the factors influencing on the proposed method are investigated by simulation also. The investigations reveal that the focus position in beamforming, the SNR of echo signal, and the wave size of liquid level have impact on the suggested method. However, it is indicated that the good performance of the proposed method remains, provided that the focus in beamforming is properly set in every scanning direction and the noise of echo signal is effectively controlled. [ABSTRACT FROM PUBLISHER]

Objective: To evaluate the relationship of postoperative cervical axial pain with different vertebral distraction methods used during ACDF procedures in cervical spondylosis patients. Methods: Ninety-four single-level cervical spondylotic myelopathy patients with significantly loss of intervertebral disc height who underwent ACDF surgery in our institute between January 2018 and January 2020 were enrolled. Cervical spine lateral radiographs were taken preoperatively, 3 days, 1-month, 2-month and 6-month after the surgery. The intervertebral disc height (IDH), interfacet distance (IFD), JOA (Japanese Orthopaedic Association) score, NDI (Neck Disability Index) score, nVAS (Neck Visual Analogue Scale) score and aVAS (Arm Visual Analogue Scale) score were measured. The correlation of clinical parameters and intervertebral disc height was evaluated. Then the correlation of clinical outcomes and different distraction method was evaluated. The patients were randomly divided into two groups, one uses Casper pin distractor system alone for distraction (Caspar alone group) and the other uses spreader assisted distraction method (Casper + spreader group). In biomechanical study, four cervical spine cadavers were selected for facet pressure measurements under different vertebral distraction methods, and the facet joint pressure was measured using force sensors. Results: Satisfactory cervical fusion and neurological recovery were achieved in all patients. No significant correlation of IDH, IFD, JOA, NDI or aVAS with nVAS score was found. No significant difference between the change in disc height and clinical outcomes was found. However, by comparing the clinical parameters of patients in different vertebral distraction groups, we found significant changes in the early nVAS and NDI scores (P = 0.11, P = 0.48) of the Casper + spreader group (3 days postoperation), and was associated with a better nVAS score at 2 months postoperation (P < 0.05). The biomechanical study in cervical cadavers also showed significantly and continuously decreased facet joint pressure in the spreader assisted vertebral distraction group (P < 0.01). Conclusions: Spreader-assisted vertebral distraction method effectively alleviates postoperative neck pain in degenerative cervical spondylosis patients treated with ACDF. The mechanism may be related to the transient relief of facet joint pressure during the vertebral distraction procedure in ACDF. [ABSTRACT FROM AUTHOR]

Background: Although ACDF has been widely used in treating cervical spondylosis and related diseases, the complications along with this anterior surgical technique have hindered its application and affected the postoperative outcome of the patients. Here, we investigated the clinical and radiological outcomes of a new integrated low-profile anterior plate and cage system for anterior cervical discectomy and fusion (ACDF) in treating cervical spondylosis. Methods: A total of 96 cervical spondylosis patients who underwent single-level ACDF between 2018 to 2020 in our institute were enrolled. There were 28 patients using the new implants and 68 patients using the zero-profile (Zero-P) implants. The Japanese Orthopedic Association (JOA) score and the visual analog scale (VAS) were used to evaluate the clinical outcomes. The cervical and segmental Cobb angle and range of motion (ROM) were used to assessed the radiological outcomes. Incidence of complications were also recorded. All data were recorded at pre-operation, 6-month and 12-month post-operation. Results: All patients were followed-up for at least 1-year, the mean follow-up time was over one year. The fusion rate was similar in the two groups. There was no significant difference in the postoperative JOA score recovery rate, postoperative VAS score of neck and arm pain, postoperative ROM, and incidence of complications between two groups (P > 0.05). However, postoperative cervical and segmental Cobb angle were better maintained in the new low-profile implant group compared to Zero-P group. Conclusions: The clinical outcomes of the new low-profile implant were satisfactory and comparable to that of zero-profile system. It may have advantages in improving and maintaining the cervical lordosis, and can be an alternative device for single-level cervical spondylosis treated with ACDF. [ABSTRACT FROM AUTHOR]

• An analytical model for multi-layered sediment amendment system is developed. • A new solution methodology is introduced to solve advection-diffusion equations. • Impacts of flow and sediment properties on the sediment cap performance are analyzed. An analytical model is developed for contaminant advection-diffusion-degradation in a contaminant containment system of multiple layers of porous media such as a clean substrate or cap placed above contaminated sediment. Typically, sediment cap is modeled as a stratified system consisting of a biologically active zone (BAZ), cap protection layer (CPL), sorbent or chemical isolation layer (CIL), and contaminated sediment layer (CS). Diffusion, advection, linear equilibrium sorption, and first-order biodegradation processes are all included in this model. The proposed analytical solution is concise and easy to implement by introducing an innovative solution methodology combining the separation of variables and the transfer matrix method. The analytical solution is verified against existing analytical and numerical solutions. A comparative analysis of the two scenarios of treating the source as a constant concentration boundary and a finite initial concentration distribution is conducted. The solutions can be used for the design of a multi-layer containment system, verification of numerical models, and evaluation of experimental data. An analytical model can easily be used to understand the effects of key model parameters and the effects of the mass transfer coefficient at the benthic boundary layer, the biodegradation in BAZ, and the absorption capacity of CIL are investigated for diffusion-dominated and advection-diffusion scenarios. Results show that advection, adsorption and biodegradation significantly affect contaminant transport while mass transfer in the benthic boundary layer is important only under some circumstances. [ABSTRACT FROM AUTHOR]

• A polyphenol embedded PTMC coating was prepared by solvent volatilization method. • The embedded polyphenol could complex with Mg2+ to promote corrosion resistance. • The coating had self-healing ability for scratch and polarization breakdown. • The coating improves the biocompatibility of Mg. Biodegradable magnesium-based vascular stent has become a research hotspot in the field of interventional medical engineering. However, the rapid degradation rate and inadequate biocompatibility of magnesium-based vascular stents often lead to implant failure in biomedical applications. It is of great research significance to slow down the degradation rate of magnesium-based stents and impart them with multifunctional bioactivity through surface modification. In this study, a self-healing coating with embedding of polyphenols is developed to create on the surface of magnesium towards corrosion protection and biocompatibility. By controlling and studying the self-healing responsiveness of the coating, the corrosion resistance under vascular implantation conditions is investigated. The embedding of polyphenols endows the interface a self-healing capability, which might be drawn as the chelation between phenol/metal ions and the formation of intermolecular connection between each of the chelating units which ultimately cause enhanced corrosion protection. Furthermore, the evaluation of biocompatibility indicates that the polyphenol-loaded polymer layer shows good biocompatibility, which is beneficial for the repair of the vascular microenvironment. These results suggest significant potential applications of this composite coating in magnesium-based vascular stents. [ABSTRACT FROM AUTHOR]

Magnesium (Mg)-based alloys have been recognized as desirable biodegradable materials for orthopedic implants. However, their clinical application has been limited by rapid degradation rates, insufficient antibacterial and osteogenic-promotion properties. Herein, a MgF 2 priming layer was first constructed on AZ31 surface. Then, dopamine and polyphenols (EGCG) were cross-linked onto this AZ31-F surface to promote osteogenesis and further enhance corrosion protection, followed by chemical grafting of antimicrobial peptides (AMPs) via Michael-addition and Schiff-base reaction to confer antibacterial properties. In vitro electrochemical corrosion tests showed that i corr of AZ31-FE/AMPs (4.36×10 -7 A/cm 2 ) is two orders of magnitude lower than that of AZ31 (4.17×10 -5 A/cm 2 ). In vitro immersion degradation showed that AZ31-FE/AMPs exhibited the lowest hydrogen release (2.38 mL) after 400 h immersion with the lowest hydrogen evolution rate among them. Further, AZ31-FE/AMPs displayed inhibitory effects against S. aureus and E. coil in the initial stage and even after 7 days immersion in PBS (antibacterial rate > 85 %). AZ31-FE/AMPs promoted ALP secretion and calcium nodule formation in MC3T3-E1 cells. Transcriptome sequencing results indicated that osteogenic promotion mechanism of AZ31-FE/AMPs in MC3T3-E1 may involve the PI3K-Akt signalling pathway. Further, AZ31-FE/AMPs enhanced new bone formation when implanted in a rat femoral bone defect model. This coating strategy addresses initial antibacterial and later osteogenesis needs based on the corrosion control, which is crucial for the surface design of Mg-based implants. STATEMENT OF SIGNIFICANCE: It is critical for magnesium-based orthopedic implants to achieve sequential functions in the bone repair process while controlling an appropriate degradation rate. A MgF 2 priming layer/phenolic-amine grafted AMPs (antimicrobial peptides) duplex coating was constructed on AZ31 surface in this study. The MgF 2 layer provided a basic corrosion protection to magnesium substrate, and dopamine and polyphenols (EGCG) were then cross-linked to the MgF 2 pretreated AZ31 to promote osteogenesis and enhance corrosion resistance, followed by chemical grafting of AMPs to confer antibacterial property. This strategy effectively meets the initial need for infection resistance and later osteogenic promotion on the basis of controlling the substrate corrosion rate, thus holding significant implications for the surface design of magnesium-based implants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Inc. All rights reserved.)

Activated carbon (AC) has been applied widely in water treatment as a strong sorbent for organic contaminants and, more recently, in-situ treatment and capping for remediating legacy contaminants. In some sediment environments, the sorption kinetics onto AC may significantly impact remedial performance, particularly for large, highly hydrophobic contaminants such as PCBs, but there is limited kinetic data on such compounds. In this study, batch experiments were conducted over 52 weeks to measure PCB adsorption kinetics on 2 ACs in granular (1.1 mm diameter) and powdered (0.02 mm) form using polydimethylsiloxane (PDMS) fibers to measure aqueous concentrations over time. The experiment was conducted in glass containers with water at known PCB concentration and containing 10 mg/L natural organic matter (NOM) and activated carbon. Blanks without activated carbon were used to estimate kinetics and equilibrium uptake to PDMS and NOM. The PDMS measured aqueous concentration in AC containing slurries was then used to estimate kinetics and equilibrium uptake of the various PCBs onto the AC. Achieving equilibration of PCBs onto the powdered activated carbon (PAC) was accomplished in days to weeks, but granular activated carbon (GAC) uptake was not complete for some high molecular weight congeners in a year. The data were used to fit linear driving force models with both linear and Freundlich models of equilibrium. The models were then used to predict uptake onto powdered and granular AC during in-situ capping and treatment using the CapSim model. Slow kinetics can significantly limit the performance of granular AC in high upwelling (> 1-10 cm/day) environments. This study demonstrates the usage of polymeric passive samplers to explore sorption kinetics and equilibrium for low solubility compounds as well as the differences in performance of granular and powdered forms of AC for remediation of PCB contaminated sediment., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Danny Reible reports financial support was provided by ADA Carbon Solutions LLC., (Copyright © 2023. Published by Elsevier Ltd.)

Objective: Osteogenesis imperfecta (OI) is a congenital disorder characterized by muscle defect and skeletal fragility, and no cure is yet available. Crosstalk between bone and muscle has become a new coming focus of therapeutic strategy in OI. Irisin, a secreted myokine, was found to be involved in regulating bone metabolism, and may be beneficial for the treatment of OI. However, its effects in OI have yet to be determined. This study sought to determine whether Irisin therapy is capable of reducing fracture risk in OI and to investigate the potential mechanisms of action., Methods: Fibronectin type III domain containing 5 (FNDC5)/Irisin expression was assessed by enzyme-linked immunosorbent assay (ELISA) and immunohistochemical staining. In vivo, X-ray was used for fracture counting and micro-CT, dynamic histomorphometry analysis, immunohistochemistry, histomorphometry, and biomechanical test were used to evaluate the effects of Irisin on fracture frequency and bone quality in OI mouse model, oim/oim mouse. In vitro, osteogenesis-related gene expressions were determined by quantitative real-time PCR (qRT-PCR), western blot, and osteoblastogenesis assay were assessed by alkaline phosphatase (ALP) staining and alizarin red S (ARS) staining. Mechanistically, cell immunofluorescence staining, co-immunoprecipitation (co-IP) (Co-IP), molecular docking, western blot, luciferase reporter assay, and chromatin immunoprecipitation (ChIP) assay were used for elucidating the mechanisms of how Irisin antagonized transforming growth factor-β (TGF-β)/Smad signaling in oim/oim osteoblasts and further attenuated the inhibitory effect of TGF-β1 on osteogenic differentiation., Results: Musculoskeletal system-related FNDC5/Irisin was decreased in the serum, muscle, and bone in oim/oim mice. Irisin administration reduced bone fracture and attenuated bone abnormalities by improving bone mass and strength and facilitating the expression of osteogenic differentiation markers. In vivo study and in vitro experiments showed that Irisin antagonized TGF-β/Smad signaling by interfering with TGF-β1-TGF-β receptor II (TβRII) binding. In oim/oim osteoblasts, Irisin alleviated TGF-β1-induced suppression of osteogenic differentiation through both integrin-dependent and integrin-independent mechanisms. Independent of integrin receptors, Irisin affected osteogenesis by activating ERK/p38 signaling and counteracting TGF-β/Smad2/3 signaling. In particular, Irisin alleviated TGF-β1-induced inhibition of Runx2 function at the osteocalcin promoter through decreasing Smad2/3 signaling and inducing HADC4/5 degeneration., Conclusions: Collectively, Irisin could effectively reduce bone fracture in oim/oim mice through promoting osteogenesis and counteracting TGF-β/Smad signaling., Translational Potential Statement: Findings from this study provided evidence for using Irisin as a potential therapeutic reagent to prevent the progression of OI., Competing Interests: Bin Sun, Huiqiao Wu, Jiajia Lu, Rongcheng Zhang, Xiaolong Shen, Yifei Gu, Changgui Shi, Ying Zhang and Wen Yuan declare that they have no conflict of interest., (© 2022 Published by Elsevier B.V. on behalf of Chinese Speaking Orthopaedic Society.)

Ossification of the posterior longitudinal ligament (OPLL) is an emerging spinal disease caused by heterotopic ossification of the posterior longitudinal ligament. The pathological mechanism is poorly understood, which hinders the development of nonsurgical treatments. Here, we set out to explore the function and mechanism of small extracellular vesicles (sEVs) in OPLL. Global miRNA sequencings are performed on sEVs derived from ligament cells of normal and OPLL patients, and we have showed that miR-320e is abundantly expressed in OPLL-derived sEVs compare to other sEVs. Treatment with either sEVs or miR-320e significantly promote the osteoblastic differentiation of normal longitudinal ligament cells and mesenchymal stem cells and inhibit the osteoclastic differentiation of monocytes. Through a mechanistic study, we find that TAK1 is a downstream target of miR-320e, and we further validate these findings in vivo using OPLL model mice. Together, our data demonstrate that OPLL ligament cells secrete ossification-promoting sEVs that contribute to the development of ossification through the miR-320e/TAK1 axis., (© 2022. The Author(s).)

Aim: We conducted a novel classification system of degenerative lumbar spinal stenosis (DLSS) based on clinical manifestations and imaging (computed tomography and magnetic resonance imaging) features. We chose different minimally invasive surgical procedures according to our system. Clinical parameters and radiological findings will be assessed in the article., Material and Methods: A retrospective study was conducted on 96 patients undergoing minimally invasive surgery for DLSS. We chose different surgical procedures according to our novel classification system based on clinical manifestations, imaging features, and concurrence with other spinal diseases. Clinical parameters and radiological findings were assessed pre- and postoperatively., Results: The mean follow up period was 24 months (range, 15~36 months). There was a statistically significant improvement in the Visual Analogue Scale (VAS) score of low back pain and leg pain after surgery (p < 0.05). According to the Japanese Orthopaedic Association (JOA) scores, the operation efficacy was excellent in 57 cases, good in 36 cases, and fair in 3 cases. According to Bridwell's criterion, the fusion rate was 96% (48/50) in patients who underwent fusion surgery. There were no cages or pedicle screws related complications., Conclusion: Minimally invasive surgical treatment of DLSS has satisfactory outcomes according to the novel classification, but further long-term, prospective, randomized controlled studies involving a larger study group are needed to validate the long-term efficacy.