In vivo analysis of ankle joint kinematics and ligament deformation of chronic ankle instability patients during level walking

Introduction: Chronic ankle instability (CAI) carries a high risk of progression to talar osteochondral lesions and post-traumatic osteoarthritis. It has been clinically hypothesized the progression is associated with abnormal joint motion and ligament elongation, but there is a lack of scientific evidence.Methods: A total of 12 patients with CAI were assessed during level walking with the use of dynamic biplane radiography (DBR) which can reproduce the in vivo positions of each bone. We evaluated the uninjured and CAI side of the tibiotalar and subtalar joint for three-dimensional kinematics differences. Elongation of the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and posterior talofibular ligament (PTFL) were also calculated bilaterally.Results: For patients with CAI, the dorsiflexion of the tibiotalar joint had reduced (21.73° ± 3.90° to 17.21° ± 4.35°), displacement of the talus increased (2.54 ± 0.64 mm to 3.12 ± 0.55 mm), and the inversion of subtalar joint increased (8.09° ± 2.21° to 11.80° ± 3.41°). Mean ATFL elongation was inversely related to mean dorsiflexion angle (CAI: rho = −0.82, P < 0.001; Control: rho = −0.92, P < 0.001), mean ATFL elongation was related to mean anterior translation (CAI: rho = 0.82, P < 0.001; Control: rho = 0.92, P < 0.001), mean CFL elongation was related to mean dorsiflexion angle (CAI: rho = 0.84, P < 0.001; Control: rho = 0.70, P < 0.001), and mean CFL elongation was inversely related to mean anterior translation (CAI: rho = −0.83, P < 0.001; Control: rho = −0.71, P < 0.001). Furthermore, ATFL elongation was significantly (CAI: rho = −0.82, P < 0.001; Control: rho = −0.78, P < 0.001) inversely correlated with CFL elongation.Discussion: Patients with CAI have significant changes in joint kinematics relative to the contralateral side. Throughout the stance phase of walking, ATFL increases in length during plantarflexion and talar anterior translation whereas the elongation trend of CFL was the opposite. This understanding can inform the development of targeted therapeutic exercises aimed at balancing ligament tension during different phases of gait. The interrelationship between two ligaments is that when one ligament shortens, the other lengthens. The occurrence of CAI didn’t change this trend. Surgeons might consider positioning the ankle in a neutral sagittal plane to ensure optimal outcomes during ATFL and CFL repair

Preparation and optimization of poly (lactic-co-glycolic acid) rod-shaped particles in nano size range for paclitaxel delivery

Nanoparticle shape has been acknowledged as an important design parameter due to its influence on nanoparticle interaction with biological systems. However, there is lacking of simple and scalable preparation technique for drug loaded non-spherical polymeric nanoparticles for a long time, thus hindering the potential applications. Although our previous research has modified the traditional emulsion solvent evaporation technique by adding guest molecules to prepare non-spherical poly (lactic-co-glycolic acid) (PLGA) particles, it is difficult to obtain nano-sized rods with minor axis less than 200 nm, which may have great potential in cancer therapy. Herein, in present research, the two-step ESE method was used and optimized to prepare poly (lactic-co-glycolic acid) nanorods for paclitaxel delivery. Firstly, the single-factor experiment was used to screen the influence of multi-factors including type of guest molecules, concentration of guest molecules, emulsification method, surfactant concentration, oil volume, poly (lactic-co-glycolic acid) concentration on the size and shape to determine the range of variables; based on the above range, a multi-factor and multi-level orthogonal experiment was designed. The formula is evaluated by the rod fabrication yield and the aspect ratio of major axis to minor axis. The results showed that the yield of nanorods in the optimal formula was 99% and the aspect ratio was 5.35 ± 2.05 with the minor axis of 135.49 ± 72.66 nm, and major axis of 657.77 ± 307.63 nm. In addition, the anti-cancer drug paclitaxel was successfully encapsulated in PLGA nanorods by the same technique. Our results not only enrich the ESE technique for preparing small sized poly (lactic-co-glycolic acid) nanorods, but also envision the potential application of nanorods for targeted cancer therapy with the delivery of paclitaxel

Does Bloggers’ Comment Response Pay off? Evidence from an Online Video Community

Content providers in online communities are becoming more active in responding to viewers’ comments. However, what benefits content providers can gain from their comment response behavior remains unclear. Based on the norm of reciprocity and the construct of social presence, this research aims to examine whether responding to viewers’ comments can enhance viewers’ intention to reciprocate towards content providers. We plan to adopt a mixed-method research design that requires both observational data collected from a Chinese online video community and experimental data gathered from a randomized experiment

Gold-Film-Thickness Dependent SPR Refractive Index and Temperature Sensing with Hetero-Core Optical Fiber Structure

A simple hetero-core optical fiber (MMF-NCF-MMF) surface plasmon resonance (SPR) sensing structure was proposed. The SPR spectral sensitivity, full width of half peak (FWHM), valley depth (VD), and figure of merit (FOM) were defined to evaluate the sensing performance comprehensively. The effect of gold film thickness on the refractive index and temperature sensing performance was studied experimentally. The optimum gold film thickness was found. The maximum sensitivities for refractive index and temperature measurement were obtained to be 2933.25 nm/RIU and −0.91973 nm/°C, respectively. The experimental results are helpful to design the SPR structure with improved sensing performance. The proposed SPR sensing structure has the advantages of simple structure, easy implementation, and good robustness, which implies a broad application prospect

Online Video Sharing Platform: Exploring Factors Affecting User Tipping Behavior

In this study, we examine user tipping behavior on China\u27s leading online video platform, BiliBili.com. We analyze a dataset of 57,767 videos and categorize them into two types: knowledge content and entertainment content. We investigate the differences in user tipping behavior between these content types and also explore the impact of contributor experience and content length on tipping behavior. Additionally, we investigate the moderating effect of content type on these influencing factors. Our findings reveal that compared to entertainment content, knowledge content receives fewer tipping rewards from users. We also find that contributor experience has a negative impact on user tipping behavior, while content length has a positive impact

Preparation technology of glass microspheres reinforced silicone resin and its application as abradable coating for stator component in aero-engine

The abradable coating is one of the significant stator components in aero-engine，which protects the rotating blade and casing by abrading itself and improves the engine performance by reducing the gap between the rotor and stator. In this study，taking the addition-type silicone resin as the matrix，the effect of diameter and stacking density of glass hollow/solid microspheres on the processability of abradable coating was investigated. Moreover，the effect of glass microsphere type and content was illustrated using a self-designed wear tester simulating the working conditions of stator in aero-engine. The results show that the silicone resin reinforced by H-type （size distribution 20–820 um） hollow glass microspheres exhibits excellent surface quality，flowability and comprehensive performance. The suitable preparation technology of abradable coatings was developed by glass microsphere selection，content controlling，tool design and infusion parameters optimizing. The as-prepared glass microsphere/silicone abradable composite is successfully applied and verified in aero-engine stator component

Reduced-Thickness-Dependent Polarized Light Transmittance of Magnetic Fluids under Longitudinal Magnetic Field

The polarized light transmittance of magnetic fluids under longitudinal magnetic field (parallels the propagation direction of the incident light) is simulated theoretically. The investigated samples are with different reduced thickness (d/λ) in a wide range. Theoretical simulations reveal that the sample reduced thickness has a significant influence on the polarized light transmittance. The thin and thick samples have distinctly different dependence of polarized light transmittance on magnetic field strength. Based on the reduced-thickness- and magnetic-field-dependent polarized light transmittance, several magnetic-fluid-based photonic devices are proposed and discussed

Fiber-Optic Magnetic Field Sensing Based on Microfiber Knot Resonator with Magnetic Fluid Cladding

A kind of all-fiber magnetic field sensing structure is proposed and demonstrated here. The sensing element includes a microfiber knot resonator (MKR) cladded with magnetic fluid (MF). The low-index MgF2 slab is adopted as the substrate. The sensitivity increases with the decrease of the MKR ring diameter. The achieved maximum magnetic field sensitivity is 277 pm/mT. The results of this work have the potential to promote the development of magnetically controllable optical devices and the design of ultra-compact cost-effective magnetic field sensors