/UV Synergistic Aging of Polyester Polyurethane Film Modified by Composite UV Absorber

The pure polyester polyurethane (TPU) film and the modified TPU (M-TPU) film containing 2.0 wt.% inorganic UV absorbers mixture (nano-ZnO/CeO2 with weight ratio of 3 : 2) and 0.5 wt.% organic UV absorbers mixture (UV-531/UV-327 with weight ratio of 1 : 1) were prepared by spin-coating technique. The accelerated aging tests of the films exposed to constant UV radiation of 400 ± 20 µW/cm2 (313 nm) with an ozone atmosphere of 100 ± 2 ppm were carried out by using a self-designed aging equipment at ambient temperature and relative humidity of 20%. The aging resistance properties of the films were evaluated by UV-Vis spectra, Fourier transform infrared spectra (FT-IR), photooxidation index, and carbonyl index analysis. The results show that the composite UV absorber has better protection for TPU system, which reduces distinctly the degradation of TPU film. O3/UV aging of the films increases with incremental exposure time. PI and CI of TPU and M-TPU films increase with increasing exposure time, respectively. PI and CI of M-TPU films are much lower than that of TPU film after the same time of exposure, respectively. Distinct synergistic aging effect exists between ozone aging and UV aging when PI and CI are used as evaluation index, respectively. Of course, the formula of these additives needs further improvement for industrial application

Role of the ortho-bridge system in the length unstable subtrochanteric femur fracture in school going children: a retrospective clinical study of 19 cases

BackgroundTreating subtrochanteric femur fractures in pediatric patients remains challenging, and an optimal fixation device has yet to be established. This study aimed to asess the clinical and radiological outcomes of Ortho-Bridge System (OBS) treatment for length-unstable subtrochanteric femur fractures in children aged 5–16 years.MethodsWe conducted a retrospective review of pediatric patients with subtrochanteric femur fractures treated with OBS between January 2018 and December 2021. The study included 19 children (12 boys, 7 girls) with an average age of 10.4 ± 2.6 years. Two of the patients had pathological fractures associated with aneurysmal bone cyst. Demographic information, mechanism of accident, fracture type, associated neurovascular injuries, surgical duration and blood loss, were collected from the hospital database. Time to union and postoperative complications were recorded. Clinical and radiological outcomes were assessed using the Harris scoring system at the latest follow-up.ResultsInjuries resulted from vehicle accidents in 10 patients (52.6%), falls over 3 meters in height in 3 patients (15.8%), and sports-related injuries in 6 patients (31.6%). The average patient weight was 41.5 kg (range: 21–78). Of the fractures, 14 (73.7%) were complex, and 5 (26.3%) were spiral. The average surgical duration was 111 min (range: 90–180), and the average surgical blood loss was 134 ml (range: 70–300). The mean time to union was 12.7 weeks (range: 8–16). No cases of infection, malunion, implant failure, or femoral head osteonecrosis were reported. Leg length discrepancy of 10 mm was observed in one patient. All patients achieved excellent results according to the Harris scoring system.ConclusionThis study suggests that the OBS may serve as an effective alternative fixation option for managing length-unstable subtrochanteric femur fractures in school-aged children

Design and Optimization of Multiclocked Embedded Systems Using Formal Techniques

Today’s system-on-chip and distributed systems are commonly equipped with multiple clocks. The key challenge in designing such systems is that two situations have to be captured and evaluated in a single framework. The first is the heterogeneous control-oriented and data-oriented behaviors within one clock domain, and the second is the asynchronous communications between two clock domains. In this paper, we propose to use timed automata and synchronous dataflow to model the dynamic behaviors of the multiclock train-control system, and a multiprocessor architecture for the implementation from our model to the real system. Data-oriented behaviors are captured by synchronous dataflow, control-oriented behaviors are captured by timed automata, and asynchronous communications of the interclock domain can be modeled as an interface timed automaton or a synchronous dataflow module. The behaviors of synchronous dataflow are interpreted by some equivalent timed automata to maintain the semantic consistency of the mixed model. Then, various functional properties that are important to guarantee the correctness of the system can be simulated and verified within the framework. We apply the framework to the design of a control system described in the standard IEC 61 375 and several bugs are detected. The bugs in the standard have been fixed, and the new version has been implemented and used in the real-world subway communication control system

Two-dimensional material integrated micro-nano fiber, the new opportunity in all-optical signal processing

With the development of all-optical networks, all-optical devices have become a research hotspot in recent years. Two-dimensional materials, represented by graphene and black phosphorus, have attracted great interest in the scientific community due to their excellent optical, electrical, magnetic, and mechanical properties. Bridging the gap between fiber optics and nanotechnology, microfibers can interact with light and matter at the micro or even nanoscale. By combining two-dimensional materials with microfibers, composite waveguides can be formed. They have the advantages of high nonlinear effect, all-fiber structure, and high damage threshold, etc. The composite waveguide can be directly applied to optical fiber communication systems, and plays an important role in the field of all-optical signal processing with a huge application prospect. In this review, the properties of typical 2D materials are first introduced. Next, the preparation methods of the relevant equipments are introduced and compared. Then, the all-optical signal processing technology based on 2D material-integrated microfiber composite waveguide is reviewed. The latest developments of all-optical modulators, all-optical wavelength converters, all-optical logic gates and all-optical thresholding devices are presented. Finally, the challenges and opportunities for the future development of 2D materials-integrated microfiber optoelectronic devices are summarized

The complete mitochondrial genome of Paroplapoderus tentator Faust (Coleoptera: Attleabidae)

For the first time, we report the complete mitochondrial genome of Paroplapoderus tentator Faust, which is 163,47 bp in length. The total number of genes in the genome was 41, including 13 PCGs; 2 rRNA genes; 19 tRNA genes; and 7 replication initiation region OHs. The genome consisted of 39.32% A, 34.17% T, 9.75% C, and 16.76% G. Phylogenetic trees indicate that Paroplapoderus is closely related to Apoderus. This study provided additional information on molecular biology for the research of Attelabidae, laying the foundation for further research on their phylogenetics