Types Of Joints Research Articles

The association between joint Serum Neurofilament Light Chain and type 2 diabetes with all-cause and cardiovascular mortality in US adults: a longitudinal study of NHANES

BackgroundIn the past, there has been a clear conclusion regarding the sole impact of serum neurofilament light chain (sNfL) levels or type 2 diabetes mellitus (DM) on the risk of death. However, the combined effect of sNfL levels and type 2 DM on all-cause and cardiovascular mortality is still uncertain.MethodsThis study was a prospective cohort study based on data from the National Health and Nutrition Examination Survey (NHANES). The sNfL levels were measured through immunological methods using blood samples collected during the survey. The diagnosis of diabetes was based on rigorous criteria, and participants’ mortality data were followed up until December 31, 2019. Firstly, we separately examined the effects of sNfL and type 2 DM on all-cause and cardiovascular mortality, and finally studied the comprehensive impact of the combination of sNfL and type 2 DM on the risk of mortality. Cumulative Kaplan-Meier curves, multivariate logistic regression and sensitivity analysis were incorporated throughout the entire study.ResultsParticipants in the highest quartile of sNfL were observed. Multivariable COX regression model showed that increased sNfL levels and type 2 DM were respectively associated with an increased risk of all-cause and cardiovascular mortality. Furthermore, elevated sNfL levels were significantly associated with an increased risk of all-cause mortality and cardiovascular mortality after adjustment for confounding factors. When considering both elevated sNfL levels and type 2 DM, individuals had a significantly increased risk of mortality. Sensitivity analysis confirmed the robustness of the findings.ConclusionsThese results suggest that elevated levels of sNfL and type 2 DM are associated with an increased risk of all-cause and cardiovascular mortality, and that participants with increased sNfL levels associated with type 2 DM have higher all-cause mortality and cardiovascular mortality.

A novel Osteoarthritis scoring system to separate typical OA joint degeneration from non-typical lesions in male Sprague Dawley rats

ObjectiveTo develop a novel scoring system to characterize osteoarthritis-related degeneration distinct from spontaneous subchondral bone lesions observed in the tibia and femur of male Sprague Dawley rats. MethodKnee joints from male rats following 12 weeks of a diet-induced obesity model of osteoarthritis (OA) were assessed. OA histopathological changes (OAHC) were assessed in the knee joints. All scores were evaluated using a modified Mankin score and a modified Osteoarthritis Research Society International histological score. OAHC were divided into 3 categories: (I) Typical OA score evaluating the changes in cartilage structure, cellularity, proteoglycan depletion, and tidemark integrity, (II) A novel Non-typical OA score evaluating cartilage integrity, and the size of local thickening, fragmentation and degeneration along the tidemark and the size and severity of the subchondral bone lesion, and (III) Total OA score comprised of both, the Typical and the Non-typical scores. ResultsRats exposed to a high fat/high sucrose diet had higher Typical OA score compared to a control group (Chow). Non-typical and Total OA scores revealed no differences in the severity of the lesions between the HFS and the Chow group animals. All scoring systems had excellent intra- and inter-examiner reliability. ConclusionThe spontaneous bone lesions observed in male Sprague Dawley rats can obscure the effect of the diet-induced obesity if the classical scoring system is used to assess joint degeneration. The newly proposed scoring method provides a reliable method to distinguish classical OA joint degeneration from spontaneous Non-typical lesions occurring in these rats.

Modulatory effects of miRNAs in doxorubicin resistance: A mechanistic view.

MicroRNAs (miRNAs) are a group of small non-coding RNAs and play an important role in controlling vital biological processes, including cell cycle control, apoptosis, metabolism, and development and differentiation, which lead to various diseases such as neurological, metabolic disorders, and cancer. Chemotherapy consider as gold treatment approaches for cancer patients. However, chemotherapeutic is one of the main challenges in cancer management. Doxorubicin (DOX) is an anti-cancer drug that interferes with the growth and spread of cancer cells. DOX is used to treat various types of cancer, including breast, nervous tissue, bladder, stomach, ovary, thyroid, lung, bone, muscle, joint and soft tissue cancers. Also recently, miRNAs have been identified as master regulators of specific genes responsible for the mechanisms that initiate chemical resistance. miRNAs have a regulatory effect on chemotherapy resistance through the regulation of apoptosis process. Also, the effect of miRNAs p53 gene as a key tumor suppressor was confirmed via studies. miRNAs can affect main biological pathways include PI3K pathway. This review aimed to present the current understanding of the mechanisms and effects of miRNAs on apoptosis, p53 and PTEN/PI3K/Akt signaling pathway related to DOX resistance.

Radiofrequency vs Steroid Injections for Spinal Facet and Sacroiliac Joint Pain: A Systematic Review and Meta-Analysis.

Pain management for spinal facet joint (SFJ) and sacroiliac joint (SIJ) pain is challenging, often requiring interventions like radiofrequency ablation (RFA) or corticosteroid injections (CI). This study aims to assess and compare the effectiveness of CI and RFA in treating SFJ and SIJ pain. We combine these treatments due to their shared pathophysiology, similar therapeutic interventions, and the necessity for an integrated approach to spinal pain management. Literature search from PubMed, Scopus, CENTRAL and Google Scholar for published studies upto 31st December 2023, and reporting data of patients who were treated using CI of RFA for SFJ and SIJ pain. Pooled standardized mean difference (SMD) with a 95% Confidence Interval (CI) was calculated. Our meta-analysis incorporated thirteen studies. Overall, patients, treated with CI had a higher pain intensity score compared to patients treated with RFA (SMD=0.92; 95% CI: 0.19 to 1.65) at 3 months, and at 6 months (SMD=1.53; 95% CI: 0.66 to 2.40) after the treatment. No significant association was reported at 12 months (SMD=1.47; 95% CI: -0.03 to 2.97). Subgroup analysis based on joint types revealed increased pain intensity scores in patients who were treated with CI for SIJ (SMD=1.25; 95% CI: 0.39 to 2.11) and SFJ (SMD=1.33; 95% CI: 0.09 to 2.57) pain. A negative but not significant effect was detected in patients, treated with CI for cervical joint pain (SMD=-0.40; 95% CI: -0.90 to 0.10). Patients treated with CI exhibited higher functional disability score compared to patients treated with RFA at 3 months (SMD=1.28; 95% CI: 0.20 to 2.35) post-treatment. This study suggests that RFA may offer superior pain relief with longer duration compared to steroid injections for spinal facet and sacroiliac joint pain. Decision regarding specific interventions should be individualized and consider patient preferences, clinical context, and potential risks.

Topology optimization with the redesigned suspension system of the internal combustion vehicle converted to an electrical vehicle

Abstract In this paper, the topology optimization of lower wishbone for a passenger car which is the converted of an internal combustion engine vehicle to an electrical vehicle was presented. On the other hand, the need to study on a suspension system arose for electrical car that was redesigned. In study, topology optimization of the structural design of the lower wishbone to be used in the front suspension was carried out by Finite Element Analysis (FEA) Method. For this purpose, firstly, the suspension spring curves and damper curves that will improve the handling, ride and comfort behaviour of the vehicle were determined, suspension system was modelled with the Multi Body Dynamics (MBD) approach. Hardpoints is necessary for vehicle dynamics and that is also an input for FEA were obtained from new suspension system via MBD analysis. In the second step, The preliminary design of the lower wishbone was created, taking into account together with the positions of the wheel drive shaft, suspension spring and brake system structural elements according to hardpoints. After designing the structure suitable for the joint types, initial design was studied on the remaining region that is for weight reduction region except the joint connection surfaces. Then, topology optimization was applied to the preliminary design for the selected load types that is come from MBD analysis. Thus, the excess volume on the preliminary design was determined for each load type. In the last stage, the results of topology optimization analysis were evaluated to reach out target weight and the producible design of the wishbone was made. Finally, Finite Element Analysis were applied to the final design for validation purposes within topology optimization work was done with the forces coming from Multi Body Dynamics. After statically solved Finite Element Analysis, a modal neutral file(.mnf) was created via FEA solver and was integrated to Adams Car as a flexbody. Flexbody was attahced to the other parts which are rigid bodies like nuckle according to Multi Body Dynamics approach. Dynamics durability cases was carried out via Adams Car. Stress results was compared to FEA results and evaluated depends on yield stress. Study results shows that the new design is lighter and competitive design and also safe in dynamics analysis for redesigned passenger car.

The influence of radon penetration through joints on the overall radon barrier properties of waterproof membranes

Waterproofing membranes with a proven ability to prevent radon penetration are commonly used to provide basic protection of buildings against radon from the subsoil. The goal of our research was to find out which types of joints of the pre-applied membranes are radon-tight and which, on the other hand, are radon permeable. Another goal was to find out how significant radon penetration through the joints can be, and how it can affect the ability of the whole radon-proof course to prevent radon penetration into the house. Six types of joints were investigated by determining the radon diffusion coefficient. Four of these types had a radon diffusion coefficient up to three orders of magnitude greater than the membranes themselves. A procedure was proposed for taking into consideration the high radon diffusion coefficient of joints in the calculation of the radon resistance of the whole radon-proof course. It has been proven that leaks in the joints can reduce the radon resistance of the whole radon-proof course by two to three orders of magnitude. For this reason, the course may not meet the minimum radon resistance requirements. Numerical simulation revealed that the leaks were due to the use of unsuitable sealing materials and technologies. A correct sealing technology for problematic joints was designed and subsequently verified.

Kinematics of human hand and robotics applications

Human kinematics is very vital to robotics study as it plays a major role in robotic development and advancement. The importance of robotics study and applications in this current era cannot be over emphasized. This paper looks at the human hand kinematics, taking cognizance of the important elements of joint types and number of joints in the human arm, with emphasis on the degree of freedom for mobility purposes. It has highlighted the multi-various capabilities of the human hand and also indicated the limitations, thus throwing more light on the possibility of maximizing these limitations and improving on the mobility and capabilities of the human hand, where new tasks and functions can be defined and robots designed and directed to carry out such functions so as to improve the productivity of its applications in various areas of Engineering. In the light of the above a new direction of research in new tasks definitions and functions are clearly opened.

Effect of joint-slippage on transmission tower performance with a simplified model of bolted joints

ABSTRACT Bolted joint behaviour is a key parameter in predicting transmission tower performance. Various types of joints are based on the number of bolts and their configuration. However, a few types of these joints were tested or modelled. In the present study, the load-deformation response of transmission tower joints as a joint behaviour was predicted using a simplified numerical model. Then, available experimental load-deformation responses of joints were used to verify the results of the proposed model. In the last step, the joint behaviours of a 400 kV transmission tower were predicted with the proposed numerical model. Then, the evaluation of the tower’s response was done with a numerical model in ABAQUS under testing loading conditions. Lastly, the deformation of a full-scale tested tower was compared with the numerical results. The numerical model results show a good agreement with the experimental results. The ultimate strength and its corresponding displacement at the full-scale model are predicted with an error of about 4%. Moreover, the failure mode of the transmission tower was not affected by the behaviour of the joints.

Multivariate Data Analysis of Maximum Stress Concentration Factors in FRP-Retrofitted Two-Planar KT-Joints under Axial Loads for Offshore Renewables

With growing concerns about the danger of global climate change and worldwide demand for energy, the interest in the investigation and construction of renewable energy technologies has increased. Fixed platforms are a type of support structure for wind turbines composed of different types of tubular joints. These structures are under different kinds of cyclic loadings in ocean environmental conditions, which must be designed and reinforced against fatigue. In the present paper, the relationships between the parameters in DKT-joints reinforced with FRP under axial loads are investigated using several models, under 16 axial loading cases, with different nondimensional parameters and different FRP materials, and orientations were generated in ANSYS (total 5184) and analyzed. The four loading conditions that cause the maximum stress concentration factors were selected. After analyzing the 1296 reinforced models, relevant data were extracted, and possible samples were created. The extracted data were used in a multivariate data analysis of maximum stress concentration factors. The Pearson correlation coefficient is utilized to study the relationship between parameters and subsequently to make predictions. To reduce the number of variables and to group the data points into clusters based on certain similarities, hierarchical and non-hierarchical classifications are used, respectively.

Design of a Trailer Adapted for Accommodation and Transport of Beehives

There is relevant interest concerning beehives, taking into account climate change and its influence on bees’ behavior. A part of the industrial engineering sector is focusing on beekeeping applications. More specifically, the present study aims to develop a trailer for the transport of beehives adapted to be placed or fixed to a tractor or a vehicle trailer, with the objective of transporting the beehives safely and stably during transhumance. The proposed novel design relates to a trailer that incorporates a device for housing a rectangular section of the beehives, which can be adapted for fixing or housing in a vehicle or in a vehicle trailer. The device comprises a lower support structure, adapted to support a plurality of rectangular sections of beehives stacked horizontally on the lower structure, an upper frame adapted to house the beehives inside, and two or more connecting elements between the lower structure and the upper frame. The connection of the trailer with the device facilitates the loading and unloading of the beehives by mechanical means. The different parts have been designed as individual pieces and then assembly is carried out to achieve the complete design. This method of implementation is because the simulation of individual components is simpler and easier, since if it is carried out through assembly, the type of joint, such as welding, and the length of the weld would have to be indicated at each point of contact between components, along with its thickness and all the necessary parameters. Therefore, in those welding points, fixed fastenings are indicated and so will simplify it. In accordance with the individual creation of each part, its own load simulation has been carried out. Static analyses are performed taking into account structural elements of this proposed design, with restrictions and loads being established. The analysis, including upper bars and supports, has been completed with several situations. Based on stress values, deformations have been determined and calculations evaluated. The trays have been manufactured using flat steel bars and angled bars for the legs and support of the hives.

Investigating laser and ultrasonic welding of pouch cell multi-foil current collectors for electric vehicle battery fabrication

The escalating necessity for more efficient and defect-free joining of ‘ultra-thin foil collectors-to-tabs’ in electric vehicle (EV) Li-ion pouch cells motivates this study. The prevalent ultrasonic welding (USW) method for these joint types, faces limitations such as design constraints and access requirements, laser welding (LW) emerges as a promising alternative offering flexibility, one-side access and faster speeds with efficient heat input. This study aims to investigate the feasibility of LW as a viable alternative to USW for joining current collectors-to-tab joints. It compares the mechanical, metallurgical, electrical and thermal analysis of the joints to evaluate both welding techniques for joint defects. The comparison of solid-state material mixing during USW and the intermixing of aluminium (Al) and copper (Cu) during fusion LW using EDX analysis presents interesting observations in the study. The USW generates a thin transition layer with intermetallic compounds (IMCs) attributed to the diffusion of Cu into the Al matrix during joining, which is comparatively lower as in the case of LW with higher material mixing with brittle IMCs like Al2Cu and Al4Cu9. However, the joint strength of LW is comparatively lower than the USW joint attributed to the reduced fusion zone area. Furthermore, from the electrical contact resistance and the joint temperature analysis, it was found that the resistance and temperature vary by as much as 13% and 6%, respectively, for the 50 A and 75 A passing currents when the USW is replaced with the LW process.

Experimental Study on a Damage-Control and Repairable Fully Precast Beam-Column Joint

ABSTRACT A novel joint with a splice lap was proposed, which was damage-control and repairable fully precast beam-column joint (DRBJ) connected by energy-dissipating connecting steel plates to remarkably diminish the residual displacement of an RC frame under strong earthquakes and ensure the rapid rehabilitation of the structure. Four one-half scale beam-column-joint specimens were designed and fabricated in different connection forms and lap lengths, and one of the specimens was loaded again under the same conditions after repair. Low cyclic loading tests on DRBJ were conducted to investigate their hysteresis curves and energy-dissipation capacities. The test results revealed that the plastic deformation of DRBJ was concentrated on connecting steel plates, while the residual displacement was small. The deformation and bearing capacities of the short-lap joint were higher than those of the long-lap junction, and the bearing, energy consumption, and deformation capacities of the DRBJ connected by strip plates were still superior to those of the DRBJ connected by the rectangular plates. The DRBJ showed satisfactory repairability and energy-dissipation capacity with the help of the strip plates. A simplified force–displacement model was established based on the analysis of the functioning mechanism of DRBJ. The calculated results of the rotational stiffness and the test results agree well, which can provide a reference for the design of this type of splice joint.

Native and prosthetic septic arthritis in a university hospital in Saudi Arabia: A retrospective study.

Septic arthritis, whether native or prosthetic, poses a significant challenge in clinical practice due to its potentially devastating consequences. Despite its clinical importance, there remains a dearth of comprehensive studies and standardized diagnostic criteria, particularly in the Kingdom of Saudi Arabia. To investigate the epidemiology, microbiological profiles, and clinical characteristics of native and prosthetic septic joints in the Saudi Arabian population. Medical records of patients diagnosed with septic arthritis between January 1, 2015, and December 31, 2022, were retrospectively reviewed. Data regarding patient demographics, clinical presentation, microbiological cultures, treatment modalities, and outcomes were analyzed. In a retrospective review of 52 cases of septic arthritis, a balanced gender distribution was observed (1:1 ratio), with the knee being the most commonly affected joint (80.8%). Methicillin-resistant Staphylococcus aureus predominated in native joints (24.2%), while Brucella spp. was more prevalent in prosthetic joints (21.1%). Joint preservation was achieved in most cases (84.6%), with no significant difference in clinical features between native and prosthetic joints. However, certain comorbidities were more common in native joint cases, including renal impairment (P = 0.002), hemodialysis (P = 0.004), heart disease (P = 0.013), and chronic liver disease (P = 0.048). At the same time, osteoarthritis was more prevalent in prosthetic joint cases (P = 0.013). Vancomycin was the most frequently used antibiotic (26.9%), and most patients received antibiotics before joint aspiration (57.7%). Surgical intervention, predominantly arthrotomy, was required in most cases (32.7%). Notably, a significant association was found between joint type and mortality (odds ratio = 0.587, P = 0.048), as well as the Charlson comorbidity index and mortality (P = 0.001). This study highlighted distinctive microbiological profiles and etiological factors in septic arthritis cases in the Saudi Arabian population.

Influence of The Type of Laying Joint on The Mechanical Behavior of Prisms Made With Ecological Bricks

Objective: This paper proposes the study of the influence of laying joints on the mechanical behavior of masonry prisms made with ecological bricks. Method: To this end, an experimental program was developed including prisms constructed with different types of joints: laying mortar, adhesive mortar and PVA glue (polyvinyl acetate). Results and Discussion: The adhesive mortar and the conventional mortar were characterized in terms of their compressive strength, obtaining a resistance approximately 1.36 times the compressive strength of the brick (6.92±0.51 MPa), while the settlement was close (0.99%). The average compressive strengths of the prisms were very different, demonstrating that the laying joint has a significant influence on cement-based masonry. It was found that the use of adhesive mortar made it possible to increase the resistance capacity of the prisms to compression by 75%, when compared to prisms made with joints that used PVA glue. However, the laying mortar showed a similar result, at 53%. The rupture mode observed in the prisms made with sticky and conventional mortar was due to traction cracking in the brick units. Research Implications: In this study, it can be concluded that when using ecological bricks with different types of joints, the thickness and type of mortar can have a significant influence on the final strength of the materials, however thin joints tend to maximize the effects defects and reduce the resistant capacity of these masonries.

Experimental investigation on the mechanical properties and failure mechanism of key joints in a new-type prefabricated pile-wall composite structure for the open-cut tunnel

To improve the failure resistance of the lining and make use of the retaining structure, this paper proposed a novel method of adding the key joints to connect the lining with the retaining structure. Usually, the joint is the weak point of the whole structure. The failure mechanism of key joints significantly influences the design and safety of the prefabricated structure. In this study, full-scale loading tests were conducted on three types of key joints: sleeve joint, spiral stirrup joint, and U-shaped rebar joint. The joint deformation, failure mechanism, concrete strain, and reinforcement strain are investigated. The results demonstrated that the deformation and failure process of the key joints can be divided into four stages. The flexural-shear failure caused by the joint opening and the sliding of lining is considered as the main failure mode of the key joints. The U-shaped rebar joint exhibited the best mechanical performance. Furthermore, the finite element modes were created to analyze the influence of axial force and the reinforcement diameter. Combining the test and numerical analysis results, the failure mechanism was revealed. In addition, the joints’ loading-carrying capacity was increased with the increase of axial force due to the axial force limiting the joint opening. The research results provide a theoretical basis and reference for the new-type prefabricated pile-wall composite structure (PPCS).

Enhancing the performance of honeycomb core sandwich panels through friction stir spot welding strategies and fracture of lap shear specimen

The manufacturing of honeycomb core sandwich structures using friction stir spot welding (FSSW) methods as alternatives for adhesive bonded (AB) structures is examined. AB, FSSW with disk insert (FSSW_D), FSSW_D with AB (FSSW_D_AB) are adopted for the purpose. The performance during the lap shear test and the cohesive zone modeling (CZM) in the finite element (FE) simulation served as the foundation for the comparison. A homogenized core and equivalent cohesive layer were used during the numerical simulations of lap-shearing of all joints. Maximum load-carrying capacity improved significantly when the FSSW_D and FSSW_D_AB were used; the improvement ranged from 592% to 878% over AB joints. Peak load was shown to be around 24% higher in FSSW_D_AB in comparison to FSSW_D joints. The peak load-to-weight ratio of the FSSW_D_AB joints was remarkable (542% to 747%). Stiffness measurements were approximately 0.43 kN/mm for FSSW_D and 0.63 kN/mm for FSSW_D_AB joints. Microstructural analysis revealed finer grains with increased rotation speed and distinct fracture modes, with SEM showing improved ductility. The good agreement between the numerical predictions and the experimental results for all types of joints showed the usefulness of the proposed numerical model. Moreover, FE simulations-based stress analyses of the three joints provided crucial results on normal and shear stress distributions enabling the sandwich structures to be tailor-made for their intended applications.

A Comparative Study on the Performance and Microstructure of 304NG Stainless Steel in Underwater and Air Laser Welding.

In order to facilitate the application of underwater laser welding technology in in situ repairs of nuclear power plants, this study conducted comparative experiments between local dry underwater laser welding and laser welding in air on 304NG nitrogen-controlled stainless steel. The aim was to explore its microstructural evolution and mechanical properties in underwater environments. It was found that, near the fusion line of laser welding in air, columnar dendrites gradually evolved into cellular dendrites toward the weld center, eventually disappearing, resulting in a skeletal ferrite and serrated austenite structure. The underwater laser welding joints exhibited similar characteristics yet with more pronounced alternation between columnar and cellular dendrites. Additionally, the size of cellular dendrites decreased significantly, and needle-like ferrite was observed at the weld center. The hardness of underwater laser welded joints was slightly higher than that of in-air laser welded joints. Compared to laser welding in air, the strength of underwater laser welding joints increased from 443 MPa to 471 MPa, and the displacement increased from 2.95 mm to 3.45 mm, both types of welded joints exhibited a mixed mode fracture characterized by plasticity and brittleness.

MRI Evaluation of Traumatic and Non-traumatic Pathologies of the Ankle Joint and Hindfoot: A Single-Center Observational Study.

Background Pathologies affecting the ankle joint and hindfoot can present with a variety of clinical symptoms and etiologies, necessitating accurate diagnostic tools for effective management. Magnetic resonance imaging (MRI) is a valuable imaging modality for assessing these pathologies, providing detailed visualization of bone, joint, tendon, and other soft tissue abnormalities. Objectives To evaluate MRI findings in a diverse cohort of 105 participants with pathologies affecting the ankle joint and hindfoot, focusing on the prevalence and types of bone, joint, tendon, and soft tissue abnormalities. Materials and methods A single-center observational descriptive study was conducted at Dr. D. Y. Patil Medical College and Hospital and Research Centre, Pune, India, over a period from August 2022 to July 2024, involving 105 participants (54.3% male, 45.7% female) with a mean age of 39.04 years. MRI scans were analyzed to assess the prevalence of bone, joint, tendon, and soft tissue pathologies. Clinical profiles, symptom duration, and etiological classifications were documented. Results Analysis of the results obtained from 105 (N = 105) study participants revealed that pain (94.3%, or 99 cases) was the most common symptom, followed by restricted movement (86.7%, or 91 cases), trauma history (75.2%, or 79 cases), and swelling (73.3%, or 77 cases). Traumatic causes (76.2%, or 80 cases) predominated, while inflammatory (48.3%, or 14 cases) and infective (34.5%, or 10 cases) causes were also significant. MRI findings showed marrow edema in 41.9%, or 44 cases, subchondral cysts in 22.9% (24 cases), fractures in 17.1% (18 cases), and erosions in 10.5% of participants (11 cases). Joint involvement was most frequent in the tibiotalar (76.2%, or 80 cases) and subtalar joints (58.1%, or 61 cases). Tendon pathologies included peritendonitis (55.2%, or 58 cases) and tendinosis (23.8%, or 25 cases), with the Achilles tendon being the most frequently affected (39%, or 41 cases). Ligament injuries were predominantly sprains (46.7%, or 49 cases), with less frequent partial (18.1%, or 19 cases) and complete tears (7.6%, or eight cases). Soft tissue findings included subcutaneous edema (76.2%, or 80 cases) and bursitis (24.8%, or 26 cases). Among the study participants who presented with non-traumatic pathologies, inflammatory pathologies (48.3%, or 14 cases) were the most common, followed by infective (34.5%, or 10 cases) and neoplastic (17.2%, or five cases) pathologies. Conclusion MRI effectively identifies a wide range of pathologies in the ankle and hindfoot, with marrow edema, joint effusion, and tendon pathologies being prevalent. The study underscores the utility of MRI in diagnosing and assessing various conditions in the ankle joint complex and highlights the need for accurate imaging to guide treatment decisions. Future research should focus on correlating MRI findings with clinical outcomes to enhance diagnostic accuracy and management strategies.

Study on hysteresis performance of four-limb CFST latticed column-box girder joints based on GA-BP neural network

This study investigates the seismic performance and energy dissipation capacity of the concrete-filled steel tube (CFST) latticed column-box girder joints. A low-cycle reciprocating load test was carried out on the CFST latticed column-box girder joints with three different connection forms. Based on the test results, a genetic algorithm (GA) is developed in combination with the back propagation neural network (BPNN) model for prediction research. Using a training set of joints with single-limb diagonal and cross-diagonal braces (training set), the development of load-displacement hysteresis curves of joints with transverse diaphragm plate (test set) under low-cycle reciprocating loads is predicted. The test results are compared with those obtained from the traditional algorithms and finite element simulations. The results on the joint hysteresis performance show that all three types of joints have a good seismic performance and energy dissipation capacity. Compared with the traditional algorithms, the GA-BP model predicts more accurate results and is therefore used to predict the load-displacement hysteresis curves of CFST latticed column-box girder joints, which is shown to be convenient and feasible.

Seismic Performance of Precast Concrete Exterior Beam-Column Joint with Disc Spring Devices

ABSTRACT To improve the seismic performance of precast concrete reinforced frame structures which are widely used worldwide, and enable a certain repairable function for the precast structure after an earthquake, this paper proposes a new type of precast concrete frame joint using a full grouting sleeve connection with a disc spring device. The disc spring device was connected in series to the longitudinal reinforcement located in the plastic hinge zone at the beam end to provide a restoring force and protect the concrete. Six exterior beam-column joints consisting of one cast-in-situ beam-column joint and five precast concrete frame joints, using a fully grouted sleeve connection equipped with or without a disc spring device, were designed and fabricated. The failure process, hysteretic characteristics, and energy dissipation capacity of the joint specimens were analyzed based on reversed cyclic loading test. The results showed that the energy dissipation and seismic performance of the newly precast concrete joints equipped with the disc spring device were better than those of the precast concrete frame joints connected by ordinary grouting sleeves without a disc spring device. The disc spring device proposed in this study plays a similar role as a damper in the precast joint during loading and has the characteristics of concentrated damage as it transfers part of the damage in the joint core area to the built-in disc spring area at the beam end. Additionally, the deformation of the precast joints under a lateral seismic load was theoretically calculated, the calculated results were in good agreement with the experimental results.