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In this study, multiple tuned mass dampers (MTMDs) were studied to understand their impact on the human-induced vibration response and comfort level of a pedestrian cable-supported suspension bridge. A spatial finite element model based on a specific engineering case was established. The dynamic characteristics of the bridge under human-induced loads were investigated, and its comfort level under human-induced vibrations was analyzed using the time-history method. Then, this study adjusted the design parameters of the dampers based on various optimal damper parameter expressions. Furthermore, the damping effectiveness of MTMD under different mass ratios ( μ ) was evaluated, and it was found that increasing the mass ratio significantly impacts damping performance. Finally, determinant-TMD (TMDD) was introduced, and a comparison between the damping effect, robustness, and performance of TMDD and MTMD was conducted. The results indicate that while increasing the mass ratio does not linearly affect maximum vibration acceleration, the damping effect increases initially and then stabilizes, with a damping rate converging at approximately 55%. However, with the TMDD approach, the maximum damping rate can reach approximately 70%, enhancing comfort levels from the "minimum CL3" achieved with MTMD to the "medium CL2" level. Additionally, while TMDD's robustness is slightly inferior to MTMD at lower mass ratios, it demonstrates superior robustness at higher mass ratios. [ABSTRACT FROM AUTHOR]

Objectives To investigate the epidemic patterns of pretreatment drug resistance (PDR) and acquired drug resistance (ADR) in HIV-1 sequences from China. Methods HIV-1 pol sequences and associated epidemiological data were collected from the Los Alamos HIV Sequence Database, NCBI, HIV Gene Sequence Database and PubMed. Genotypic resistance and subtypes were identified using the Stanford HIV Drug Resistance Database. Results A total of 36 263 sequences from ART-naïve individuals and 1548 sequences from ART-experienced individuals with virological failure were evaluated. PDR prevalence was 6.64%, initially decreasing and then increasing to 7.84% (2018–22) due to NNRTI. Pooled ADR prevalence (44.96%) increased, with NNRTI and NRTI aligning with the overall trend. The percentage of multidrug resistance was more than that of single-drug resistance in PDR and especially ADR annually. PDR was most prevalent in Central China followed by Southwest and North. ADR prevalence was highest in North China followed by Northwest and Southwest. In ADR sequences, high-level resistance was more common, especially in NRTI. PDR sequences exhibited low-level or intermediate resistance, especially PI. Drug resistance mutations revealed distinct patterns in PDR and ADR. CRF01_AE, the predominant subtype in China, exhibited the highest proportions among most ART drugs and drug resistance mutations, with a few exceptions where CRF07_BC (prominent in the Northwest), CRF55_01B and CRF08_BC (prominent in the Southwest) showed the highest proportions. Conclusions HIV-1 PDR and ADR prevalence in China exhibited diverse epidemiological characteristics, underscoring the importance of ongoing national monitoring of PDR, ADR and subtype; patient education on adherence; and personalized regimens. [ABSTRACT FROM AUTHOR]

Recent evidence indicates that the damaged regions in osteoarthritis are accompanied by the accumulation of iron ions. Ferroptosis, as an iron‐dependent form of cell death, holds significant implications in osteoarthritis. Melatonin, a natural product with strong scavenging abilities against reactive oxygen species and lipid peroxidation, plays a crucial role in the treatment of osteoarthritis. This study aims to demonstrate the existence of ferroptosis in osteoarthritis and explore the specific mechanism of melatonin in suppressing ferroptosis and alleviating osteoarthritis. Our findings reveal that melatonin reverses inflammation‐induced oxidative stress and lipid peroxidation while promoting the expression of extracellular matrix components in chondrocytes, safeguarding the cells. Our research has revealed that NADPH oxidase 4 (NOX4) serves as a crucial molecule in the ferroptosis process of osteoarthritis. Specifically, NOX4 is located on mitochondria in chondrocytes, which can induce disorders in mitochondrial energy metabolism and dysfunction, thereby intensifying oxidative stress and lipid peroxidation. LC‐MS analysis further uncovered that GRP78 is a downstream binding protein of NOX4. NOX4 induces ferroptosis by weakening GRP78's protective effect on GPX4 and reducing its expression. Melatonin can inhibit the upregulation of NOX4 on mitochondria and mitigate mitochondrial dysfunction, effectively suppressing ferroptosis and alleviating osteoarthritis. This suggests that melatonin therapy represents a promising new approach for the treatment of osteoarthritis. [ABSTRACT FROM AUTHOR]

Due to their high flexibility, low damping, and small mass, stay cables are prone to large-amplitude vibrations. Various mechanical measures, typically installed near the cable anchorage to the deck, have been developed to suppress cable vibration. These dampers, however, may not be effective for ultralong cables since the damper is close to the cable anchorage, the cable node. In this paper, a tuned mass damper (TMD)/nonlinear energy sink (NES) are considered for installation between two adjacent stay cables for vibration mitigation. Firstly, the static equilibrium equation of the stay cable–damper system is established, and the influence of the self-weight of the damper on cable shape is investigated. The governing equations describing the motion of the two adjacent cables with a damper are then established using the Hamilton principle, which are then solved by the method of separation of variables. For cases of swept-sine excitation and harmonic excitation, the optimal designs of TMD and NES are achieved with the purpose of suppressing the first- and third-mode-dominated vibrations, respectively. Both optimal TMD and NES may substantially suppress cable vibrations, with each having advantages under certain situations. Finally, the dynamic response characteristics of two adjacent cables with an optimal damper are analyzed. Interesting dynamic behaviors, such as energy input suppression, phase shift, cable frequency shift, and phase diagram boundary rotation, are identified, and their mechanisms are explained. [ABSTRACT FROM AUTHOR]

Field-programmable gate array (FPGA) has become an excellent hardware accelerator solution for convolutional neural networks (CNNs). Meanwhile, optimizing methods, such as model compression, have been proposed. As most CNN accelerators focus on dense neural networks, to solve the problem of difficult hardware deployment due to irregular networks, we propose a method for sparse neural networks in our work. The storage and coding format of sparse data obtained by the block pruning method is designed to make it friendly to implement on FPGA. Besides, we also propose an efficient and simple data flow by the planarization of the whole convolution calculation process. The experimental result demonstrates that our implementation can achieve clock frequency of 190 MHz, power consumption of 13.32 W and inferencing speed of 16.37 ms. Compared with some typical Mobilenet implementation schemes, our method has been proven to achieve a better balance between frequency, accuracy, power consumption, and speed. [ABSTRACT FROM AUTHOR]

Introduction: Osteoarthritis (OA) is the most prevalent and debilitating joint disease without an effective therapeutic option. Multiple risk factors for OA have been identified, including abnormal chondrocyte miRNA secretion and circadian rhythms disruption, both of which have been found to cause progressive damage and loss of articular cartilage. Environmental disruption of circadian rhythms in mice predisposes animals to cartilage injury and OA. Methods: The role of miR-195/497 cluster during OA progression was verified by mouse OA model with intra-articular injection of Agomir and Antagomir. We performed micro-CT analysis, Osteoarthritis Research Society International scores, and histological analysis in mouse knee joints. RNA sequencing was performed on the mouse cartilage cell line to explore the molecular mechanism of the miR-195/497 cluster and proteins in signaling pathway were evaluated using Western blot. Senescence-associated phenotypes were detected by Western blot, senescence β-galactosidase staining, and immunofluorescence. Results: This study demonstrated that miR-195/497-5p expression is disrupted in OA with senescent chondrocytes. In addition, miR-195/497-5p influenced the circadian rhythm of mice chondrocytes by modulating the expression of the Per2 protein, resulting in the gradual degradation of articular cartilage. We found that the miR-195/497 cluster targets DUSP3 expression. The deletion of the miR-195/497 cluster increased the level of DUSP3 expression and decreased the levels of phosphorylated ERK 1/2 and CREB. Per2 transcription is upregulated by stimulating CREB and ERK 1/2 phosphorylation. Conclusion: Our findings identify a regulatory mechanism connecting chondrocyte miR-195/497-5p to cartilage maintenance and repair and imply that circadian rhythm disturbances affected by miR-195/497-5p are risk factors for age-related joint diseases such as OA. [ABSTRACT FROM AUTHOR]

The vibration behavior of the maglev train–bridge system has consistently been a primary concern in developing low-to-medium-speed maglev transportation. In this study, based on the planned maglev train crossing the Xiangjiang River Bridge, the total vibration potential energy of the maglev train is extracted using a mathematical method. Following the principle of minimum total dynamic potential energy in elastic systems and the “set-in-right-position” rule, the equations of motion for the maglev train–bridge coupled system are established. The analytical framework and solution process of the coupling equation are developed using the pseudo-excitation method and evolutionary spectrum theory. The dynamic responses of the long-span continuous girder bridge, subjected to moving maglev trains, are analyzed through a Fortran program. The natural frequency and dynamic coefficient of the bridge structure are calculated, and the dynamic response parameters are obtained. Finally, the vibration comfort of the bridge is evaluated using the Diekemann and Sperling indices. The results indicate that the bridge vibration is within acceptable limits, demonstrating that the analyzed dynamic response parameters can serve as reliable references for the construction and design of magnetically suspended long-span continuous girder bridges, both in daily operation and management. [ABSTRACT FROM AUTHOR]

Pharmacologic treatment of orthopedic diseases is a common challenge for clinical orthopedic surgeons, and as an important step in the stepwise treatment of orthopedic diseases, it is often difficult to achieve satisfactory results with existing pharmacologic treatments. Therefore, it is increasingly important to find new ways to effectively improve the treatment pattern of orthopedic diseases as well as to enhance the therapeutic efficacy. It has been found that metal-organic frameworks (MOFs) possess the advantages of high specific surface area, high porosity, chemical stability, tunability of structure and biocompatibility. Therefore, MOFs are expected to improve the conventional traditional treatment modality for bone diseases. This manuscript reviewed the applications of MOFs in the treatment of common clinical bone diseases and look forward to its future development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhao, Wang, Liu, Bai, Jiang, Mao, Ying, Dong, Yi and Li.)

Objective: This study aims to analyze the biomechanical characteristics of posterolateral plateau fractures fixed by a novel anatomical plate using finite element analysis., Methods: A three-dimensional digital model of the full length of right tibiofibula was obtained by CT scanning. A posterolateral tibial plateau fracture model was then created. The acquired fracture model was assembled with 4 groups of internal fixations: Group A, novel anatomical plate; Group B, straight buttress plate; Group C, oblique T-shaped locking plate; Group D, two lag screws. Axial loads of 500, 1,000 and 1,500 N perpendicular to the horizontal plane were used to simulate the stress on the lateral plateau of a 65 kg person standing, walking and fast running., Results: Vertical displacements of the posterolateral fragments in each of the four groups gradually increased under loads from 500 N to 1,500 N. The maximum displacement of the fracture fragment in four groups were all located on the lateral side of the proximal part, and the displacement gradually decreased from the proximal part to the distal end. The maximum displacement values under the axial load of 1,500 N was in the following order: novel anatomical plate (1.2365 mm) < oblique T-shaped locking plate (1.314 mm) < two lag screws (1.3747 mm) < straight buttress plate (1.3932 mm). As the axial load increased, the stress value of the different internal fixation models gradually increased. The stress behavior of the same internal fixation model under different loads was similar. The maximum stress value under the axial load of 1,500 N was in the following order: novel anatomical plate (114.63 MPa) < oblique T-shaped locking plate (277.17 MPa) < two lag screws (236.75 MPa) < straight buttress plate (136.2 MPa)., Conclusion: The patients with posterolateral plateau fractures fixed with a novel anatomical plate in standing, walking and fast running can achieve satisfactory biomechanical results, which lays the foundation for future applications. At the same time, clinical fracture types are often diverse and accompanied by damage to the soft tissue. Therefore, the ideal surgical approach and appropriate internal fixation must be selected based on the patient's injury condition., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Jian, Jiang, Li, Zhou, Yu and Yi.)