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Mechanoluminescence, a smart luminescence phenomenon in which light energy is directly produced by a mechanical force, has recently received significant attention because of its important applications in fields such as visible strain sensing and structural health monitoring. Up to present, hundreds of inorganic and organic mechanoluminescent smart materials have been discovered and studied. Among them, strontium‐aluminate‐based materials are an important class of inorganic mechanoluminescent materials for fundamental research and practical applications attributed to their extremely low force/pressure threshold of mechanoluminescence, efficient photoluminescence, persistent afterglow, and a relatively low synthesis cost. This paper presents a systematic and comprehensive review of strontium‐aluminate‐based luminescent materials’ mechanoluminescence phenomena, mechanisms, material synthesis techniques, and related applications. Besides of summarizing the early and the latest research on this material system, an outlook is provided on its environmental, energy issue and future applications in smart wearable devices, advanced energy‐saving lighting and displays. Mechanoluminescence materials have recently attracted significant research interest due to their enormous modern applications in energy, sensing, anti‐counterfeiting, wearable display, and sport science. Strontium‐aluminate‐based luminescent materials’ mechanoluminescence is reviewed on the phenomena, mechanisms, material synthesis techniques, and related application.

Abstract Stress sensing is the basis of human-machine interface, biomedical engineering, and mechanical structure detection systems. Stress sensing based on mechanoluminescence (ML) shows significant advantages of distributed detection and remote response to mechanical stimuli and is thus expected to be a key technology of next-generation tactile sensors and stress recorders. However, the instantaneous photon emission in ML materials generally requires real-time recording with a photodetector, thus limiting their application fields to real-time stress sensing. In this paper, we report a force-induced charge carrier storage (FICS) effect in deep-trap ML materials, which enables storage of the applied mechanical energy in deep traps and then release of the stored energy as photon emission under thermal stimulation. The FICS effect was confirmed in five ML materials with piezoelectric structures, efficient emission centres and deep trap distributions, and its mechanism was investigated through detailed spectroscopic characterizations. Furthermore, we demonstrated three applications of the FICS effect in electronic signature recording, falling point monitoring and vehicle collision recording, which exhibited outstanding advantages of distributed recording, long-term storage, and no need for a continuous power supply. The FICS effect reported in this paper provides not only a breakthrough for ML materials in the field of stress recording but also a new idea for developing mechanical energy storage and conversion systems.

The development of real-time and accurate visual stress detection is crucial for the field of building engineering. Herein, a new strategy is explored for the development of novel cementitious materials by hierarchical aggregation smart luminescent material and resin-based material. The cementitious material with such layered structure is inherently capable of visualization of stress monitoring and recording by converting the stress to visible light. The specimen fabricated by the novel cementitious material could repetitively emit green visible light under excitation of a mechanical pulse for 10 cycles, suggesting that the cementitious material shows highly reproducible performance. Moreover, the numerical simulations and analysis for the models of stress indicate that the luminescent time is synchronous with the stress and the emission intensity is proportional to the value of stress. To the best of our knowledge, this is the first study that the cementitious material realizes visible stress monitoring and recording, which supplies new insights for exploring modern multi-functional building materials.

2020 is bound to be a difficult year. The rapid spread of COVID-19 has had a huge impact on public life, public health and even the entire industry. But at the same time, online services are also on the rise. As the most active marketing method in the Internet era, brand co-branding still played a role during the epidemic. At present, China has achieved phased victory in the epidemic prevention campaign, and we have also ushered in the post-epidemic era of small-scale outbreaks. Many brands in the post-epidemic era, as the main victims of the epidemic, are also constantly exploring new ways of brand co-branding. In this case, in order to find a new method for the brand co-branding of Zhouheiyadian in Wuhan in the new era, the author will analyze the factors that affect the development of the regional brand co-branding of Zhouheiyadian in the form of big data and questionnaires: first, analyze the factors, classifications and policies that affect the regional brand from the four aspects of packaging, brand, marketing and service, and put forward suggestions; Secondly, it analyzes the factors that affect regional brands, and puts forward suggestions from three aspects: convenience of purchase, reputation and selectivity; The third is to analyze the factors affecting regional brands from three aspects of purchase price, brand and publicity mode, and put forward suggestions to find brand co-branding forms suitable for the post-epidemic era.

Objective To evaluate the clinical efficacy of internal fixation versus hemiarthroplasty in the treatment of unstable intertrochanteric fractures in the elderly. Methods A search was conducted in PubMed, Web of Science, Embase, and Cochrane Library databases up to April 2020. The present study compared internal fixation and hemiarthroplasty in the treatment of unstable intertrochanteric fractures in the elderly. RevMan5.3 software provided by the International Cochrane Group was used for the meta‐analysis. To compare the differences in the operation time, intraoperative bleeding, length of hospital stay, superficial infection, Harris hip score, mortality within 1 year, mortality within 2 years, reoperation, incidence of deep venous thrombosis (DVT), partial weight‐bearing time, non‐union, and implant‐related complications between an internal fixation group and an hemiarthroplasty group. Results A total of 1300 patients were included in nine studies. The results showed that the operation time (MD = −18.09, 95% CI: −27.85–−8.34, P = 0.0003), intraoperative bleeding (MD = −195.31, 95% CI: −244.8–−147.74, P < 0.0001), implant‐related complications (MD = 3.83, 95% CI: 1.74–8.45, P = 0.0008), and partial weight‐bearing time (MD = 17.21, 95% CI: 1.63–32.79, P = 0.03) have statistical significance. However, there is not statistical significance for the Harris hip joint function scale (HHS) (MD = 5.60, 95% CI: −1.13–12.33, P = 0.10), DVT (MD = 1.02, 95% CI: 0.45–2.27, P = 0.97), length of hospital stay (MD = ‐1.08, 95% CI: −2.82–0.66, P = 0.22), superficial Infection (OR = 0.92, 95% CI: 0.43–1.98, P = 0.89), mortality within 1 year (OR = 0.95, 95% CI: 0.61–1.48, P = 0.81), mortality within 2 years (OR = 0.93, 95% CI: 0.61–1.43, P = 0.75), reoperation (MD = 1.80, 95% CI: 0.64–5.04, P = 0.26), and non‐union (OR = 1.20, 95% CI: 0.48–3.03, P = 0.70). The result of the subgroup analysis showed no significant differences between the less than 2 years follow‐up and the 2 years or more follow‐up group. The only difference was for the Harris hip score: the internal fixation group was superior to the hemiarthroplasty group in the less than 2 years subgroup analysis, while there was no difference between the internal fixation group hemiarthroplasty group in the 2 years or more subgroup analysis. Conclusion Compared with the internal fixation group, those in the hemiarthroplasty group could carry out weight‐bearing training early and implant‐related complications were reduced, but it requires longer operation time and there is greater intraoperative blood loss. There is no difference in mortality, the incidence of DVT, non‐union, HHS, reoperation, length of hospital stay, and superficial infection. Hemiarthroplasty may be a better choice for unstable intertrochanteric fractures in the elderly.

Tibial cortex transverse transport (TTT) surgery is an extension of the Ilizarov technique. Based on the law of tension‐stress, its primary function is to rebuild microcirculation which can relieve ischemic symptoms and promote wound healing. It has received more and more scholars' attention and has experienced a series of changes for 20 years since it entered PR China. The mechanisms involved have gradually become clear, such as the reconstruction of the polarization balance of macrophages, the promotion of vascular tissue regeneration, and the mobilization and regulation of bone marrow‐derived stem cells. TTT technique is mainly used in the treatment of chronic ischemic diseases of the lower extremities. It has recently been successfully used in the treatment of primary lymphedema of the lower extremities. A series of improvements have been made in the external fixator's style, the size of skin incision and osteotomy, and distraction method. For example, the annular external fixator has been redesigned as a unilateral external fixator, and accordion technology has been introduced. For distraction methods after surgery, there was no uniform standard in the past. The technique can also be used in combination with other treatments to achieve better effects, such as interventional therapy, negative pressure sealed drainage, 3D printing technology, traditional Chinese medicine. Nevertheless, the surgery may bring some complications, such as secondary fracture, nail infection, skin necrosis at the surgical site, etc. Reports of complications and doubts about the technique have made the TTT technique controversial. In 2020, the relevant expert consensus was published with treatment and management principles, which might guide the better application and development of this technique. The surgery of tibial transverse transport has shown definite efficacy in the treatment of chronic ischemic diseases of the lower extremities and may be gradually applied to the treatment of primary lymphedema in the future. With the gradual understanding of its mechanism of action, the continuous improvement of the technique, and the publication of relevant expert consensus, its clinical application will be further guided.

Congenital pain insensitivity is a rare genetic disease and its clinical manifestations are many. In orthopaedics, common complications of this disease include painless fracture and Charcot's arthropathy. We followed up a case of multiple fractures of the lower extremity in two years, during which time he came to the clinic for five painless fractures of the lower extremity in a total of six parts. A mutation was found on the NTKRI gene (chr1:156813923(hg19), NM_001007792.1: c.1221938C > T). We have developed a combination of surgery and conservative treatments for his condition, focusing on the mental state of the child and considering comprehensive treatment to be the best option for this type of patient. Occult fractures caused by pain insensitivity are often treated only as fractures, however their complications require routine examination and cleaning, suitable protective shoes, splint fixation, stretching, guided exercise planning, and early treatment of injuries. Due to the risk of fracture in the future, it is important that parents pay attention to the behavior and psychology of the child, such as not letting the child participate in exercise with a risk of injury, protective measures while playing, engaging in psychological counseling, and inducing interest in mental activity. These interventions will play a very important role in preventing the recurrence of fracture.

Abstract This paper aims to investigate the influence of periodicity temperature change on the properties of dry granular materials in macroscopic and microscopic. A series of cyclic thermal consolidation tests have been carried out based on the discrete element method (DEM) that incorporate particles’ volumetric thermal expansion coefficient. The simulation of the direct shear test was carried out on the samples after thermal cycling. Results showed that thermally-induced volumetric strain accumulation of the specimen can be calculated by the DEM model, based on the two-dimensional particle flow code (PFC2D) software. The lateral pressure degraded concomitantly thanks to decreases in particles’ horizontal contact during periodic thermal cycling. In addition, the shear dilatancy level decreases during the shearing process with the number of thermal cycles. Both the size and anisotropy of the normal contact force and contact number and the force chain are affected by the temperature cycle. Finally, the results of this paper have a certain reference for the engineering practice, such as thermal piles or others, when granular materials are subjected to thermal cycling.

This paper describes a case of using a pile-slab composite foundation to handle a bridge-end bump problem. Conventionally, a deep-seated concrete slab method is employed to tackle this problem; however, this method generates a large stress concentration within 1 m from the bridge end. The mechanical bearing capacity of the deep-seated concrete slab is insufficient and prone to structural damage. Further, the longitudinal slope change rate is also very high. To overcome these limitations and solve the problem, a lower partition slab-pile foundation treatment method is proposed. The construction of the proposed method is provided, and the results of a case study analyzed by field monitoring and a simulation executed using ABAQUS finite element simulation show good agreement. The results indicate that the mechanical bearing characteristics for the proposed lower partition slab-pile foundation treatment method are better than the conventional deep-seated concrete slab method, and therefore, the structure is more resistant to damage. In addition, because the pile foundation enhances the foundation bearing capacity, the longitudinal slope change rate of the new pile-slab composite foundation is 2.5 times that for the deep-seated concrete slab technology. Thus, the lower partition slab-pile foundation treatment method can better deal with the bridge end bump problem.

To investigate the value of subtypes of completely reversed flow (CRF) waveform in vertebral artery (VA) on Doppler ultrasound in differentiation occlusion from severe stenosis of the ipsilateral proximal subclavian artery (SA). A total of 357 patients with CRF in the VA on Doppler US were reviewed retrospectively. Among them, 49 patients (mean age, 68.2 ± 7.8 years) confirmed by digital subtraction angiography (DSA) were included. According to the status of diastolic flow, the CRF was divided into continuous CRF (CCRF, = 27) and intermittent CRF (ICRF, = 22). The correlation of subtypes of CRF waveform and VA parameters with the severity of SA stenosis was evaluated. The severity of SA stenosis was determined by DSA. Of those 49 patients, SA occlusion was observed in 33 patients (67%, occlusion group) and severe stenosis in 16 patients (33%, stenosis group). The subtypes of CRF waveforms showed a significant between-group difference ( = 0.005). CCRF exhibited an accuracy of 85.2% (23/27) in diagnosing SA occlusion. The diameter of the target VA with ICRF showed a significant between-group difference ( = 0.041). The target VA diameter ≥ 3.8 mm in ICRF achieved an accuracy of 81.8% (18/22), and its combination with CCRF achieved an accuracy of 83.7% (41/49) in the differentiation of SA occlusion from severe stenosis. Subtypes of CRF in VA can help to differentiate SA occlusion from severe stenosis. CCRF has higher accuracy in diagnosing SA occlusion. The CCRF waveform plus VA diameter in ICRF is more accurate for differentiating SA occlusion from severe stenosis.