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Dynamization, that is, increasing interfragmentary movement (IFM) by reducing fixation stiffness from a rigid to a more flexible state, has been successfully used in clinical practice to promote fracture healing. However, it remains unclear how dynamization timing and degree affect bone healing of different fracture types. Finite element models of tibial fractures based on the OTA/AO classification (Simple: A1‐Spiral, A2‐Oblique, A3‐Transverse; Wedge: B2‐Spiral, B3‐Fragmented; Complex: C2‐Segment, C3‐Irregular), in combination with fuzzy logic‐based mechano‐regulatory tissue differentiation algorithms, were used to simulate the healing process when dynamization of varied degrees (dynamization coefficient or DC = 0‐0.9; 0.9 represents 90% reduction in the fixation stiffness relative to a rigid fixation) were applied at different time points after fracture. The fuzzy logic‐based algorithms have been validated with a preclinical animal model. The results showed that the healing responses of type A fractures were more sensitive to the changes in dynamization degree and timing comparing with type B or C fractures. Additionally, the optimal dynamization regime for each fracture type was different. For type A fractures, a moderate dynamization degree (e.g., DC = 0.5) applied after Week 1 promoted the recovery of biomechanical integrity. For type B and C fractures, the effective dynamization included a greater dynamization degree (DC = 0.7) applied after Week 2. Our results further demonstrated that the fracture morphology affected interfragmentary strain environments within the callus, leading to varied healing results for different fracture types. These results suggest that the effects of dynamization are highly dependent of the fracture types. Therefore, specific dynamization strategies should be chosen for different fracture types to achieve optimal healing outcomes. [ABSTRACT FROM AUTHOR]

This article discusses the use of magnetic resonance imaging (MRI) to obtain CT-like images for the assessment of vertebral disorders. Low back pain is a major health issue, and vertebral pathologies are a common cause. While CT scans are commonly used, they involve radiation exposure, especially in pediatric patients. MRI-derived CT-like images offer a radiation-free alternative and have been shown to accurately display bone structures. The article presents a study comparing the diagnostic value of different MRI sequences with conventional CT and histopathology, demonstrating the potential of MRI-derived CT-like images in the assessment of vertebrae. [Extracted from the article]

Dynamization, increasing the interfragmentary movement (IFM) by reducing the fixation stiffness from a rigid to a more flexible condition, is widely used clinically to promote fracture healing. However, it remains unknown how dynamization degree (relative change in fixation stiffness/IFM from a rigid to a flexible fixation) affects bone healing at various stages. To address this issue, we used a fuzzy logic‐based mechano‐regulated tissue differentiation algorithm on published experimental data from a sheep osteotomy healing model. We applied a varied degree of dynamization, from 0 (fully rigid fixation) to 0.9 (90% reduction in stiffness relative to the rigid fixation) after 1, 2, 3, and 4 weeks of osteotomy (R1wF, R2wF, R3wF, and R4wF) and computationally evaluated bone regeneration and biomechanical integrity over the healing process of 8 weeks. Compared with the constant rigid fixation, early dynamization (R1wF and R2wF) led to delays in bone bridging and biomechanical recovery of the osteotomized bone. However, the effect of early dynamization on healing was dependent of the degree of dynamization. Specifically, a higher dynamization degree (e.g., 0.9 for R1wF) led to a prolonged delay in bone bridging and largely unrecovered bending stiffness (48% relative to the intact bone), whereas a moderate degree of dynamization (e.g., 0.5 or 0.7) significantly enhanced bone formation and biomechanical properties of the osteotomized bone. These results suggest that dynamization degree and timing interactively affect the healing process. A combination of early dynamization with a moderate degree could enhance the ultimate biomechanical recovery of the fractured bone. [ABSTRACT FROM AUTHOR]

Background: MRI‐based finite element analysis (MRI‐FEA) is the only method able to assess microstructural and whole‐bone mechanical properties of the hip in vivo. Purpose: To examine whether MRI‐FEA is capable of discriminating age‐related changes in whole‐bone mechanical performance and micromechanical behavior of the proximal femur, particularly considering the most common hip fracture‐related sideways fall loading. Study Type: Retrospective. Subjects: A total of nine younger (27 ± 3.2 years) and nine elderly (61 ± 3.9 years) healthy volunteers. Field Strength/Sequence: 3T; 3D fast field echo sequence. Assessment: The left proximal femurs were scanned and FE models created. FEA was performed to simulate sideways fall and stance loading for each femoral model. Apparent stiffness and high‐risk (90th percentile) tensile and compressive strains of the proximal femur as well as the average strains within cubic regions of the femoral neck and greater trochanter were assessed. Statistical Tests: Paired and unpaired t‐tests. Results: Compared to the young group, the femoral stiffness of the elderly decreased by 39% and 40% (both P < 0.05) under the sideways fall and stance conditions, respectively. Accordingly, the high‐risk tensile and compressive stains were elevated with aging (40% and 23% for sideways fall, 23% and 11% for stance conditions; all P < 0.05). However, the loading configuration‐induced difference was only observed in the elderly group for the high‐risk strains (22% for tension and 12% for compression; both P < 0.05). Additionally, compared to the stance condition, the sideways fall increased the average tensile (young: 108%, elderly: 123%; both P < 0.05) and compressive strains (young: 631%, elderly: 617%, both P < 0.05) within the greater trochanter rather than the femoral neck region. Data Conclusion: In vivo MRI‐FEA is capable of capturing age‐related changes in both apparent‐level stiffness and tissue‐level micromechanical behavior of the proximal femur. However, the effect of sideways fall loading might be better reflected by tissue‐level micromechanics rather than apparent stiffness. Level of Evidence: 3 Technical Efficacy Stage: 1 [ABSTRACT FROM AUTHOR]

In this report, a mixed‐metal cation‐based halide perovskite (HP) CsPb1−xTixBr3 quantum dots (QDs) were first embedded in the B–Si–Zn glasses using a traditional approach of melt quenching and heat treating. A battery of test results such as photoluminescence, X‐ray diffraction, and time‐resolved attenuation prove that Ti ions do not destroy the properties of CsPbBr3, and they are successfully doped into CsPbBr3. At the same time, the doping of Ti ions also reduces the toxicity of lead. By altering the ratio of Pb/Ti, we determined the optimum ratio of CsPb0.7Ti0.3Br3 QDs through experimental data. Due to the excellent optical properties and stability of CsPb0.7Ti0.3Br3 QDs glass, it was designed to construct the white‐light emitting diode device with tunable color coordinate, color rendering index, correlated color temperature, and a high luminous efficiency compared with CsPbBr3 QDs glass, which may be a promising candidate for the field of lighting and displays. [ABSTRACT FROM AUTHOR]

Long noncoding RNA KCNQ1OT1 participates in the regulation of imprinted genes within the kcnq1 domain. But its roles in carcinogenesis and metastasis remain largely elusive. Herein, we evaluated its potential in non‐small‐cell lung cancer (NSCLC) progression. We demonstrated that the KCNQ1OT1 level was upregulated in NSCLC tissues and cell lines. High KCNQ1OT1 level correlated with poor overall and progression‐free survival in NSCLC patients. KCNQ1OT1 facilitated proliferation, migration, and invasion in H460 cells. Furthermore, knockdown of KCNQ1OT1 reduced the expression of HSP90AA1. KCNQ1OT1 presented a positive correlation with HSP90AA1 which predicted the tumor progression in NSCLC from The Cancer Genome Atlas database. Intriguingly, KCNQ1OT1 modulated HSP90AA1 expression by sponging miR‐27b‐3p. MiR‐27b‐3p counteracted the effect of KCNQ1OT1 on HSP90AA1 expression, H460 cell migration, and invasion. These data revealed a role for KCNQ1OT1 as an oncogene through miR‐27b‐3p/HSP90AA1 axis during NSCLC progression. Long noncoding RNA KCNQ1OT1 promotes non‐small‐cell lung cancer progression. KCNQ1OT1 modulates HSP90AA1 expression by sponging miR‐27b‐3p. [ABSTRACT FROM AUTHOR]

Defects in cable joints, induced in the process of manufacturing or assembling, can alter the distribution of the electrical field seriously. To investigate the impacts of different defects on electrical field distribution in cable joints, equivalent models of 110 kV cable joints with needle damage, impurity defect and scratch in insulation are established, respectively. The distribution of electrical potential and field strength in cable joints with dissimilar defects is obtained by finite element analysis (FEA). The results indicate that the needle damage, among the three different defects, generates most excessive electrical field strength distortion surrounding the defect, even exceeding the breakdown strength of air. The results show that these defects can easily result in partial discharge (PD), which leads them to pay more attention to the operation of cable joints. [ABSTRACT FROM AUTHOR]

The paper proposes a key frame extraction method for video copyright protection. The fast and robust method is based on frame difference with low level features, including color feature and structure feature. A two-stage method is used to extract accurate key frames to cover the content for the whole video sequence. Firstly, an alternative sequence is got based on color characteristic difference between adjacent frames from original sequence. Secondly, by analyzing structural characteristic difference between adjacent frames from the alternative sequence, the final key frame sequence is obtained. And then, an optimization step is added based on the number of final key frames in order to ensure the effectiveness of key frame extraction. Compared with the previous methods, the proposed method has advantage in computation complexity and robustness on several video formats, video resolution, and so on. [ABSTRACT FROM AUTHOR]

Distraction osteogenesis (DO) is widely utilized for treating limb length discrepancy, nonunion, bone deformities and defects. This study sought to develop a 4D time‐lapse morphometry method to quantify bone formation and resorption in mouse femur during DO based on image registration of longitudinal in vivo micro‐CT scans. Female C57BL/6 mice (n = 7) underwent osteotomy, followed by 5 days of latency, 10 days of distraction and 35 days of consolidation. The mice were scanned with micro‐CT at Days 5, 15, 25, 35, 45, and 50. Histological sectioning and Movat Pentachrome straining were performed at Day 50. After registration of two consecutive micro‐CT images of the same bone (day x and day y), the spatially‐ and temporally‐linked sequences of formation, resorption and quiescent bones at the distraction gap were identified and bone formation and resorption rates (BFRdayx‐y and BRRdayx‐y) were calculated. The overall percentage error of the registration method was 2.98% ± 0.89% and there was a strong correlation between histologically‐measured bone area fraction and micro‐CT‐determined bone volume fraction at Day 50 (r = 0.89, p < 0.05). The 4D time‐lapse morphometry indicated a rapid bone formation during the first 10 days of the consolidation phase (BFRday15–25 = 0.14 ± 0.05 mm3/day), followed by callus reshaping via equivalent bone formation and resorption rates. The 4D time‐lapse morphometry method developed in this study allows for a continuous quantitative monitoring of the dynamic process of bone formation and resorption following distraction, which may offer a better understanding of the mechanism for mechano‐regulated bone regeneration and aid for development of new treatment strategies of DO. [ABSTRACT FROM AUTHOR]