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This paper focuses on the finite-time guaranteed cost (FTGC) control problem for interval type-2 (IT2) fuzzy semi-Markov switching systems (S-MSSs) with additive disturbances. Based on the IT2 fuzzy S-MSSs and the state feedback control method, a novel IT2 mode-dependent fuzzy GC controller is developed under the mismatched membership functions. Then, some new sufficient conditions are given to ensure that IT2 fuzzy S-MSSs are FT stochastically stable based on the designed IT2 mode-dependent fuzzy GC controller. Furthermore, the transition rates boundaries condition is relaxed, and a new incomplete transition rates boundaries model is constructed to reflect the transition rates information. With a view to both the incomplete transition rates boundaries and the actuator fault phenomenon, the improved stability criteria are provided to stabilize the IT2 fuzzy S-MSSs within a FT interval and determine the gains of the IT2 mode-dependent fuzzy GC controller, resulting in a much greater design flexibility. Distinct from the existing results, the presented FTGC control scheme is more suitable for many practical systems, because the IT2 fuzzy S-MSSs model which is more general compared with the traditional fuzzy system and S-MSSs is considered. Finally, three illustrative examples are offered to explain the effectiveness and feasibility of proposed FTGC control approach.

Background This study aims to construct and verify a nomogram model for microvascular invasion (MVI) based on hepatocellular carcinoma (HCC) tumor characteristics and differential protein expressions, and explore the clinical application value of the prediction model. Methods The clinicopathological data of 200 HCC patients were collected and randomly divided into training set and validation set according to the ratio of 7:3. The correlation between MVI occurrence and primary disease, age, gender, tumor size, tumor stage, and immunohistochemical characteristics of 13 proteins, including GPC3, CK19 and vimentin, were statistically analyzed. Univariate and multivariate analyzes identified risk factors and independent risk factors, respectively. A nomogram model that can be used to predict the presence of MVI was subsequently constructed. Then, receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were conducted to assess the performance of the model. Results Multivariate logistic regression analysis indicated that tumor size, GPC3, P53, RRM1, BRCA1, and ARG were independent risk factors for MVI. A nomogram was constructed based on the above six predictors. ROC curve, calibration, and DCA analysis demonstrated the good performance and the clinical application potential of the nomogram model. Conclusions The predictive model constructed based on the clinical characteristics of HCC tumors and differential protein expression patterns could be helpful to improve the accuracy of MVI diagnosis in HCC patients.

Intervertebral disc degeneration (IDD) has been identified as one of the predominant factors leading to persistent low back pain and disability in middle-aged and elderly people. Dysregulation of Prostaglandin E2 (PGE2) can cause IDD, while low-dose celecoxib can maintain PGE2 at the physiological level and activate the skeletal interoception. Here, as nano fibers have been extensively used in the treatment of IDD, novel polycaprolactone (PCL) nano fibers loaded with low-dose celecoxib were fabricated for IDD treatment. In vitro studies demonstrated that the nano fibers had the ability of releasing low-dose celecoxib slowly and sustainably and maintain PGE2. Meanwhile, in a puncture-induced rabbit IDD model, the nano fibers reversed IDD. Furthermore, low-dose celecoxib released from the nano fibers was firstly proved to promote CHSY3 expression. In a lumbar spine instability-induced mouse IDD model, low-dose celecoxib inhibited IDD in CHSY3wt mice rather than CHSY3−/− mice. This model indicated that CHSY3 was indispensable for low-dose celecoxib to alleviate IDD. In conclusion, this study developed a novel low-dose celecoxib-loaded PCL nano fibers to reverse IDD by maintaining PGE2 at the physiological level and promoting CHSY3 expression.

A 60-year-old male patient complained of weakness of both legs for one year, intermittent fever for two months, up to 38.0 °C. Physical examination showed bilateral hyperreflexia of knee tendon and positive Hoffman sign on the right side. MR imaging of the cervical spine showed central herniation of the cervical 5-7 disc and compression of the spinal cord. The WBC was normal, C-reactive protein was 24.42mg/l, ESR was 55mm/h, TB antibody, anti acid staining and T-SPOT were negative. Autoantibody was negative and thyroid function was normal. The JOA score was 9 points. During the operation, the herniated disc tissue was taken out for pathological examination and bacterial culture. The posterior longitudinal ligament was removed and no abscess was found. The symptom of asthenia in both legs was relieved and fever disappeared. No growth of aerobe, anaerobe or tubercle bacilli was found in the culture of resected tissue. One year after the operation, the fever did not recur, JOA score increased to 14 points, and MR imaging showed no protrusion in cervical spinal canal. In this case, the fever disappeared after the operation for cervical spondylosis, which may be a special manifestation of sympathetic nerve stimulation or autonomic dysfunction by chronic compression of spinal cord.

In this article, by using distributed consensus algorithm, the power compensation problem of network losses in a microgrid is considered with battery energy storage systems (BESSs). At first, the battery storage unit (BSU) is assembled at each node to maintain the power supply demand balance of the microgrid, then the power constraint is considered, which demands each BSU must run between its upper and lower bounds, otherwise, the upper or lower bounds will be used to replace the real power of the BSU. In order to keep the power balance of microgrid when network losses exist, a novel distributed consensus algorithm is proposed to compensate the missing power through the discharging process of BSUs, and the state of charge (SOC) of BESS is also considered. Besides, the case of battery faults is also considered, where the minimum layout point constraint is presented to ensure the completely compensation of the whole transmission losses. Finally, the test results of IEEE 14-bus and IEEE 57-bus microgrid systems are provided to verify the effectiveness and validity of the proposed method, respectively.

Hyperspectral images (HSIs) include hundreds of spectral bands, which lead to Hughes phenomenon in classification task and decrease the classification accuracy. Feature selection can remove redundant and noisy features in the HSIs to overcome this phenomenon. In real applications, we may face a HSI scene with only a few labeled samples. Meanwhile, there are adequate labeled samples in a similar HSI scene. For example, they share the same land-cover classes. The shared information can be used to help the scene with a few labeled samples in feature selection. Traditional single-scene-based feature selection appears powerless in solving such problems. Cross-scene feature selection provides an attractive way to select feature subsets by simultaneously using the information from two HSI scenes. However, spectral distribution may change due to atmospheric conditions, yielding spectral shift. In order to tackle this problem, we propose a cross-domain algorithm based on hybrid whale optimization algorithm with simulated annealing (WOASA). The newly proposed algorithm is dubbed cross-domain WOASA (CDWOASA). CDWOASA simultaneously considers the separability of different land-cover classes and the consistency of selected features between two scenes, leading to discriminative and domain-invariant characters of selected feature subset. Moreover, since the original WOASA is not able to precisely control the dimension of selected features, we propose an improvement using a sorting strategy based on the fitness function value, thus making the output feature dimension precisely controlled. The experimental results on two cross-scene HSI datasets demonstrate the superiority of CDWOASA in cross-scene feature selection.

Wheel tread wear is a form of wheel damage that can seriously affect the performance of freight vehicles. A new numerical approach to optimizing wheel profiles can reduce circular wear on the LM wheel in the design cycle. This approach considers the influence of different line conditions and speed fluctuation on wheel wear, along with the performance of the wheel and the rail as the materials wear. In this approach, a nonlinear numerical optimization model for the wheel tread profile is built through a backpropagation (BP) neural network method. The multipoint Kik–Piotrowski (KP) contact mechanics model is applied to calculate the wheel/rail normal force, tangential creep force, the stick-slip area, and the size and shape of the contact patch. The optimal profile is obtained through the genetic algorithm (GA) method. In order to better reflect the random characteristics of wheel/rail matching and interval uncertainty, a random sampling technique is used to generate a random data sample at typical operating speeds.

Lumbar disc herniation (LDH) is the most common cause of sciatica. Percutaneous endoscopic discectomy (PELD) is indicated when conservative treatments fail, which has been proved effective. During conventional PELD, ruptured discs and loose fragments inside discs are removed as much as possible to guarantee a lower reherniation rate, but it inevitably would lead to deterioration of disc degeneration and loss of disc height after PELD. Ensuring sufficient decompression while alleviating the post-operation disc degeneration process is still a clinical problem.To evaluate the imaging and clinical outcomes of bi-needle PELD with intradiscal irrigation technique for the treatment of lumbar disc herniation (LDH).Multicenter retrospective cohort study.Shanghai Changzheng Hospital, Naval Medical University, Shanghai, China.A total of 48 patients who underwent bi-needle PELD (B-PELD) or conventional-PELD (C-PELD) for LDH in our 2 spine centers were included in this study. There were 26 cases in the C-PELD group (male 12 cases, female 14 cases) with an average age of 34.6 ± 6.8 years. And there were 22 patients in the B-PELD group (male 10 cases, female 12 cases) with an average age of 35.1 ± 6.4 years. The difference in postoperative disc degeneration (Pfirrmann grades, disc-vertebra height ratios [D-V H ratios]), visual analog scale (VAS) of low back pain, and reoperation rates were compared between the 2 groups.There was no significant difference in gender, age, disease duration, and surgical level between the 2 groups (P0.05). The postoperative VAS of back pain was 2.31 ± 0.53 for the C-PELD group and 0.63 ± 0.74 for the B-PELD group; the difference was significant (P = 0.013). The difference between the preoperative and postoperative D-V H ratios in the C-PELD group was significant (P0.0001), while it was not significant in the B-PELD group (P = 0.6708). The difference between the loss of D-V H ratios after surgery was significant between the 2 groups (P = 0.0003). The loss of D-V H ratios was higher in the C-PELD group. The difference between the preoperative and postoperative Pfirrmann grades in the B-PELD group was not significant (P = 0.7261); however, it was significant in the C-PELD group (P = 0.0012). The reoperation rate in the C-PELD group was 7.7%, and the reoperation rate in the B-PELD group was 4.5%; the difference was not significant (P = 1).This study employed a retrospective design, and its inherent selection bias and limited statistical power should be considered.Bi-needle technique with saline irrigation maneuver showed a significant advantage of restoration of disc height and amelioration of disc degeneration compared to conventional PELD surgery.

Decreased cervical range of motion (ROM) is a common symptom of myelopathy patients. Many previous studies have relied on a variety of experimental approaches for quantifying static cervical range of motion. However, the change rules of time-space variation during dynamic cervical spine motion remains unknown.To develop and validate the effectiveness of a novel wearable robot-based sensor system, Analysis of Dynamic Cervical spine Motion (ADCM), in evaluating the dynamic cervical spine motion dysfunction of patients with cervical spondylotic myelopathy (CSM).A cross-sectional study.One hundred forty consecutive healthy individuals (70 men and 70 women) and 120 CSM patients (60 men and 60 women) were enrolled in the present study.The cervical motion process parameters, including the flexion and extension ROM, the flexion and extension time, and the Japanese Orthopedic Association scores (JOA) for cervical spine were measured.Two hundred and sixty consecutive participants were asked to wear ADCM system and then fully flex and extend their neck rapidly and evenly at tolerable maximum speed. The cervical motion process was recorded and converted into waveforms. Relevant waveform parameters were measured and analyzed. The number of complete flexion-extension motions in 10 seconds has been defined as 10s F-E cycles. The Japanese Orthopedics Association (JOA) scores of CSM patients were marked.CSM patients had a lower number of 10s F-E cycles than healthy subjects. There were significant differences in flexion and extension time and ROM between two groups. The waveforms of myelopathy patients were wider and lower than those in healthy individuals. The average ratio value (defined as F) of wave height to wave width (a+b/c+d) could quantitatively reflect such differences of waveforms. The average F value was correlated with the JOA scores of the cervical motion function (r=0.7538), and F value declined as JOA scores decreased. According to receiver operating characteristic curve analysis, the optimal threshold value of the normal average ratio was more than 34.7.ADCM appears to be an objective and quantitative severity assessment tool for confirmed CSM patients by evaluating dynamic cervical spine motion dysfunction.

With the train speed and axle load increasing, excessive stresses are produced and transmitted to the ballast layer, inducing rapid ballast degradation. To solve this issue, the under sleeper pads (USPs) have been widely applied between sleepers and ballast particles as the elastic layer. In this research, laboratory tests using half-sleeper track were carried out to study the ballast bed performance with or without the USPs under static and cyclic loading. Results show that applying the USPs reduces the track stiffness and can decrease the settlement. However, installing the USPs increases the ballast bed acceleration and the sleeper vertical acceleration. The contact areas of sleeper-ballast with USPs are over 5 times as those without USPs. The USPs assist reducing ballast degradation mainly by avoiding the ballast particle breakage at the sleeper-ballast interface and can increase the stress distribution at the longitudinal direction.

Mountain railway alignment optimization is known as a very complex engineering problem that should consider many factors, such as drastically undulating terrain, geological hazard impacts,...

Rolling contact fatigue damage of rails is significantly influenced by residual stresses. A three-dimensional elastic-plastic finite element model of wheel–rail contact was established in the present study, and the influence of initial stresses resulting from rail manufacturing process on the residual stress distribution of rails was analyzed. The repeated rolling passes were simulated and the stable residual stress distribution of rails was obtained. The influence of factors, such as wheel load, friction coefficient, and longitudinal creep rate, on the residual stress distribution of rails was investigated. It is found that within the limited special scale affected by the wheel–rail contact, the difference between the longitudinal residual stress with initial stresses applied and that without initial stresses applied becomes quite small once enough rolling passes have occurred (i.e., 10 rolling passes). When the initial stresses are applied, the longitudinal residual compressive stress on wheel–rail contact center of the rail is approximately 500 MPa. The residual compressive stress decreases with the increasing depth and changes from compression to tension at the depth of 6 mm beneath wheel–rail contact center of the rail. The wheel load mainly affects the residual stress distribution along the depth direction beneath rail surface. The friction coefficient mainly affects the residual stress distribution on the rail surface. The longitudinal creep rate has a great influence on the longitudinal residual stresses at the surface and along the depth of the rail.

Indications and clinical outcomes of percutaneous endoscopic thoracic discectomy(PETD) in treating thoracic disc herniation is rarely reported and still controversial. We reported an unsatisfied recovery of thoracic disc herniation with PETD, treated by a second posterior thoracic laminectomy and Ponte osteotomy.A male presented with lower extremity weakness and stagger caused by T3/4 intervertebral disc herniation. The upper thoracic curve was in excessive kyphosis with T2-5 Cobb angle of 34.3 degrees. The preoperative ODI score was 34 and Roelzs's JOA score was 14. Percutaneous transforaminal endoscopic thoracic discectomy (PETD) from a posterior lateral approach was performed. At five-month follow-up, his thoracic back pain and staggering gait did not improve. The postoperative T2-5 Cobb angle was 32.1 degrees, the ODI score was 24 and Roelzs's JOA score was 14. A second posterior thoracic decompression this time with fixation was performed, but no disc herniation was detected. A Ponte osteotomy was performed to correct the kyphosis. One month after the second surgery, muscle strength of the lower limbs was improving with the T2-5 Cobb angle decreased to 19.4 degrees, the ODI score decreased to 10 and Roelzs's JOA score increase to 16. Six month later, the ODI score decreased to 0 and Roelzs's JOA score improved to 18. In review of the literature, PETD doesn't guarantee the patient a satisfactory neurological recovery for kyphotic thoracic disc herniation. Posterior decompression with Ponte osteotomy may be beneficial to release the tension and decompression of the spinal cord tension.Thoracic disc herniation with kyphosis angle20 degrees (T2-5), percutaneous endoscopic thoracic discectomy is not likely to get good neurologic results. Posterior laminectomy with ponte osteotomy might be beneficial for these patients to induce dorsal drifting of the spinal cord from anterior herniation.

Damage in joints has a significant effect on the integrity and stability of the China Railway Track System (CRTS)II slab track. In this study, a three-dimensional finite element model was established to investigate the damage law of joints in the CRTSII slab track under temperature and vehicle loads. In the finite element model, the non-linear constitutive law and damage parameter of the interface between the slabs and the cement asphalt (CA) mortar layer were defined by a cohesive zone model. Based on the limited results in this analysis, the recommendations of joint damage repair were put forward. Results show that in the formation of joint damage in CRTSII slab track, the temperature load plays a more important role compared with the vehicle load. The more the concrete loss at the narrow joint, the lower the temperature rise at which concrete stress reaches its compressive strength. If concrete loss at the bottom of the narrow joint is no more than 10%, the damaged joint can be repaired at the time when the temperature of slabs is close to the construction temperature. If concrete loss at the bottom of the narrow joint is larger than 10%, repair strategy should be taken according to the time when the joint damage is detected. During repair, improving bond strength of the interface between the slabs and the CA mortar layer and strength of joint concrete can help to prevent the repaired joint from being damaged again.

Background: Recent studies have shown that alpha-1,3-mannosyltransferase (ALG3) promoted tumorigenesis and progression in multiple cancer types. Our study planned to explore the clinical implication and potential function of ALG3 in hepatocellular carcinoma.Materials and Methods: Data from public databases were used to analyze the ALG3 expression and its impact on the clinical significance of patients with HCC. The ALG3 expression was confirmed by qRT-PCR and Western blot. Immunohistochemistry was used to confirm the ALG3 expression and explore its clinical implication in HCC. KEGG, GO, and GSEA enrichment analyses were utilized to explore the biological pathways related to ALG3 in HCC. TIMER2.0 was applied to assess the association between ALG3 and immune infiltration. CCK8, MTT, and transwell assays were used to investigate the role of ALG3 downregulation in HCC cell lines.Results: qRT-PCR, WB, and IHC proved ALG3 was highly overexpressed in HCC tissues. The Kaplan–Meier analysis verified the overexpression of ALG3 was related to poor overall survival (p < 0.001). Multivariate cox regression analysis showed that the high ALG3 expression was an independent risk prognostic factor. GSEA and TIMER2.0 predicted that ALG3 participates in cell differentiation and cycle and correlates with immune cell infiltration. Transwell assay results showed that ALG3 silencing also impaired the invasion ability of HCC cells.Conclusion: ALG3 was overexpressed and considered a potential indicator of survival in HCC, and our findings provided a novel therapeutic target for HCC.

Recurrent low back pain after spinal surgeries, such as lumbar laminectomy, is a major complication of excessive epidural fibrosis. Although multiple preclinical and clinical methods have been aimed at ameliorating epidural fibrosis, their safety and efficacy remain largely unclear. Single implanted electrospun fibrous membranes provide physical barriers that can decrease tissue fibrosis after surgery; however, they also trigger local inflammation due to the implantation of a foreign body, thus subsequently attenuating their anti-fibrosis properties. Here, we designed a strategy that permits easy incorporation of mefloquine into polylactic acid membranes, and stable long-term mefloquine release, to potentially improve anti-fibrosis effects and relieve or prevent low back pain. The electrospun fibrous membranes grafted with mefloquine showed a well-controlled early temporary peak release, and secondary drug release occurred smoothly over several weeks. Histopathological and histomorphometric results indicated that the drug-loaded membranes had excellent anti-fibrosis effects after laminectomy in rats. Inflammation and neovascularization at the surgical site indicated that the mefloquine-grafted electrospun fibrous membranes provided sustained anti-inflammatory outcomes while effectively alleviating associated neuropathic pain hypersensitivity. In summary, our study indicated that polylactic acid-mefloquine grafted electrospun fibrous membranes may be a potential local agent to mitigate epidural fibrosis and support sensory neurological function after laminectomy, thereby potentially improving patients' postoperative outcomes.

Capecitabine (CAP) is now widely used in the comprehensive treatment of digestive system tumors. Some clinical observations have shown that CAP may have immunosuppressive effects, but there is still a lack of clear experimental verification. In this study, different doses of CAP were administered to normal mice by gavage. Our results confirmed that CAP did not cause myelosuppression in bone marrow tissue; CAP selectively reduced the proportion of T cells and the concentration of related pro-inflammatory cytokines, while it increased the concentration of anti-inflammatory cytokines. Thymidylate phosphorylase (TP) is the key enzyme for the transformation of CAP in vivo; this study confirmed that T cells express TP, but the bone marrow tissue lacks TP expression, which explains the selectivity in pharmacodynamic effects of CAP. In addition, it was confirmed that CAP can induce T cell apoptosis in vivo and in vitro. In vitro experiments showed that CAP-induced T cell apoptosis was related to TP expression, endoplasmic reticulum stress (ERS) induction, reactive oxygen species (ROS) production, and mitochondria-mediated apoptosis activation. Therefore, this study confirmed that the differential expression of TP in cells and tissues explains why CAP avoids the toxic effects of myelosuppression while inducing T cell apoptosis to exert the immunosuppressive effect. Therefore, CAP may become an immunosuppressive agent with a simultaneous anti-cancer effect, which is worthy of further studies.

Mobile edge computing has been deeply integrated with internet of vehicles (IoV) due to its efficient computing capabilities close to devices. However, the inefficiency of storage and computing capabilities for vehicle terminals is in conflict with the diversification of network application services, which poses a huge challenge to the high-performance computing in IoV. In response to the high-performance computing requirements, a mobile edge computing task distribution and offloading algorithm based on deep reinforcement learning is proposed in order to solve low terminal storage capacity and diversified network service problems. Firstly, taking the energy consumption and transmission bandwidth of vehicle terminals as constraints, this paper establishes a task offloading and resource allocation model based on mathematical model using in-vehicle communication network. Besides, the model takes the maximum task processing rate as the objective function. Secondly, the AHP-DQN framework is used to solve the model, and the optimization variables are allocated according to the real-time state of the network to ensure the better performance of the task allocation algorithm in the multi-user scenario of IoV. Finally, simulation experiments show that the proposed algorithm can effectively realize the effective distribution of computing tasks in IoV.

Sensory nerves are long being recognized as collecting units of various outer stimuli; recent advances indicate that the sensory nerve also plays pivotal roles in maintaining organ homeostasis. Here, this study shows that sensory nerve orchestrates intervertebral disc (IVD) homeostasis by regulating its extracellular matrix (ECM) metabolism. Specifically, genetical sensory denervation of IVD results in loss of IVD water preserve molecule chondroitin sulfate (CS), the reduction of CS bio-synthesis gene chondroitin sulfate synthase 1 (CHSY1) expression, and dysregulated ECM homeostasis of IVD. Particularly, knockdown of sensory neuros calcitonin gene-related peptide (CGRP) expression induces similar ECM metabolic disorder compared to sensory nerve denervation model, and this effect is abolished in CHSY1 knockout mice. Furthermore, in vitro evidence shows that CGRP regulates nucleus pulposus cell CHSY1 expression and CS synthesis via CGRP receptor component receptor activity-modifying protein 1 (RAMP1) and cyclic AMP response element-binding protein (CREB) signaling. Therapeutically, local injection of forskolin significantly attenuates IVD degeneration progression in mouse annulus fibrosus puncture model. Overall, these results indicate that sensory nerve maintains IVD ECM homeostasis via CGRP/CHSY1 axis and promotes IVD repair, and this expands the understanding concerning how IVD links to sensory nerve system, thus shedding light on future development of novel therapeutical strategy to IVD degeneration.

With the development of 5G and the explosive growth of massive Internet of Health Things devices, existing computing resource allocation strategies have many problems such as long delay and poor security performance. Therefore, this paper proposes an optimization strategy for computing resource allocation of massive IoHT devices considering privacy protection in cloud edge computing environment. Firstly, a 5G heterogeneous cloud edge computing network is constructed. Besides, according to network status, the computing requirements of devices are allocated to local execution or edge computing. The computing delay, communication and computing resource allocation of edge servers are modeled accordingly. Then, taking the delay and energy consumption of network computing resource allocation as optimization goal, the priority of subtasks is sorted to realize the optimal allocation of computing resources. Finally, a protection model for instant messaging privacy data is designed by considering the risk of large-scale privacy data leakage in IoHT. Terminal devices under the same local area network are connected to edge servers by Socket without cloud server forwarding, which improves the security performance of privacy data. Experiment and demonstrate the performance of our proposed strategy on MATLAB simulation platform. The results show that the increase of edge computing server will affect the CPU proportion. Moreover, compared with other strategies, the number of users, the number of edge computing servers, the computing capacity of devices and the task arrival rate have the least impact on the average delay of proposed strategy, which effectively improves the performance of allocation strategy.

Background We retrospectively analyzed and report the clinical results of percutaneous endoscopic lumbar discectomy (PELD) in treating patients with calcified lumbar intervertebral disc herniation (CLDH). Methods The data from 40 patients with CLDH treated with PELD in our hospital from June 2013 to June 2017 were reviewed. Of the 40 patients, 27 (19 men; 8 women; average age, 45.5 ± 7.5 years) had undergone percutaneous endoscopic transforaminal discectomy and 13 (8 men, 5 women; average age, 46.9 ± 6.9 years) had undergone percutaneous endoscopic interlaminar discectomy. The Peak method was used for both groups. The preoperative demographic data of both groups were analyzed. The pre- and postoperative leg visual analog scale scores and Oswestry disability index were compared and complications were evaluated. Results All procedures were performed successfully, and follow-up data were obtained for all patients for 24 months. The leg visual analog scale and Oswestry disability index scores at the last follow-up visit had decreased in both groups and were significantly different statistically from the preoperative data. No nerve root injury, intestinal injury, intervertebral disc infection, or recurrence was detected in any patient. Dural tear and cerebrospinal fluid leakage were observed in 3 patients (2, percutaneous endoscopic transforaminal discectomy; 1, percutaneous endoscopic interlaminar discectomy), because of adhesions between the calcification and nerve root. However, their symptoms resolved, and they were discharged after 1 week of bed rest. Conclusions With the application of Peak philosophy, PELD is safe and effective in treating patients with CLDH. The use of PELD results in good neurological recovery, pain relief, and a low incidence of complications.

—The traveling wave reflection method is proposed to locate the inter-turn short circuit fault of the circuit breaker energy storage motor coil. The capacitance and inductance matrices of the energy storage motor coil are calculated by finite element simulation, and the wave impedance model of the coil is established based on ATP-EMTP. The low-voltage square wave pulse signal is injected at the winding head to detect the characteristic curve of reflected wave when inter-turn short circuit fault occurs. The variation law of generalized fractal dimension of reflection wave characteristic curve with short circuit position is analyzed. The short-circuit position is evaluated based on BP neural network, and the evaluation accuracy is 100 %, indicating that this method is feasible.

The destruction of low oxygen microenvironment played critical roles in the pathogenesis of intervertebral disk degeneration (IVDD). In this study, high oxygen tension (HOT) treatment upregulated integrin α6(ITG α6) expression, which could be alleviated by blocking PI3K/AKT signaling pathway. And the levels of ITG α6 expression were increased in the NP tissue from IVDD patients and IVDD rat model with mild degeneration, which were reduced as degeneration degree increases. Further studies found that ITG α6 could protect NP cells against HOT-induced apoptosis and oxidative stress, and protect NP cells from HOT-inhibited ECM proteins synthesis. ITG α6 upregulation by HOT contributed to maintain a NP tissue homeostasis through the interaction with hypoxia inducible factor-1α (HIF-1α). Furthermore, silencing of ITG α6 in vivo could obviously accelerate puncture-induced IVDD. Taken together, ITG α6 upregulation by HOT in NP cells might be a protective factor in IVDD as well as restore NP cell function.

The design of grade-separated road and railway crossings can be complicated and time-consuming since the intersection point as well as the road and rail alignments should jointly optimize an objective such as minimum construction costs. Moreover, the design of grade-separated road and railway crossings should consider additional crossing constraints and possible revisions of the road alignments. However, research on alignment optimization with variable ends is scarce. In this article, a grade-separated road and railway crossing model is developed, the crossing point of which as well as both connection points with the road, are variable. Subsequently, by searching synchronously for the paths that connect different endpoints, a distance transform algorithm is applied. The effectiveness of the method is verified through a real-world case study. The results show that the proposed method can find various promising solutions that both satisfy multiple constraints and are considerable improvements on the designs produced by experienced human designers.

The joint operation of natural gas system and power system is an important direction of energy system integration. In this paper, the unit combination modeling method of integrated gas-electric energy system is studied, and the operation constraints such as output, climbing and duration considering unit startup and shutdown state are established. The matrix balance model of power system and natural gas system is established. Based on the generation transfer distribution factor, the tie line security constraints are proposed, and the simplified method of gas electric coupling model of gas turbine based on the piecewise linearization method is proposed. Finally, 6-node power system and 6-node natural gas system are used to build an integrated gas electric energy system. Taking the economic cost optimization as the optimization goal, it is verified that the unit combination constraint in this paper can effectively optimize the unit operation dispatching in the combined system.

The operation optimization of multi-heterogeneous energy system (MHE) is the key to improve energy efficiency. This paper studies the economic and emission components and establishes a multi-objective optimization model. The regional power system, natural gas system and park level cold heat system are modeled respectively to build a multi heterogeneous energy system network architecture to meet the actual application needs. The multi-objective optimization method of MHE system based on NSGA-II algorithm is studied to realize the optimization solution of economy and emission. Through the simulation analysis of the experimental case, the optimal solution set is provided for the decision-maker quickly and effectively.

This paper studies the robust H ∞ filtering problem for a class of continuous-time uncertain semi-Markov jump systems. Considering that the filter modes can be obtained via observing system modes, a semi-Markov mode-dependent filter is designed. Based on the constructed filter, the robust H ∞ filtering performance analysis is proposed by minimizing the H ∞ level for uncertain semi-Markov jump systems. Meanwhile, the sufficient conditions for existence of the designed filter are given with the help of linear matrix inequality method. The simulation results for a possible application are presented to ensure the effectiveness of the proposed method.

This paper proposes an optimal day-ahead optimization schedule for gas-electric integrated energy system (IES) considering the bi-directional energy flow. The hourly topology of electric power system (EPS), natural gas system (NGS), energy hubs (EH) integrated power to gas (P2G) unit, are modeled to minimize the day-ahead operation cost of IES. Then, a second-order cone programming (SOCP) method is utilized to solve the optimization problem, which is actually a mixed integer nonconvex and nonlinear programming issue. Besides, cutting planes are added to ensure the exactness of the global optimal solution. Finally, simulation results demonstrate that the proposed optimization schedule can provide a safe, effective and economical day-ahead scheduling scheme for gas-electric IES.

The coupling and complementary utilization of multiple energy sources is the basis of energy structure optimization, and the accommodation of renewable energy is the key issue in power system industry. In this paper, through the cooperation of gas turbine (GT) and power-to-gas (P2G) equipment, an integrated natural gas and electric power system (IGES) with bidirectional energy transmission is constructed. The gas turbine is used as the peak shaving unit of power system, and the excessive wind power is accommodated by P2G, which is converted into natural gas stored in gas storage tanks (GST). The contract model is proposed to regulate the natural gas in GST injected to pipeline network generated by P2G. Finally, the 14-bus natural gas system (NGS) and the IEEE-14-bus electric power system (EPS) are used to construct the IGES system with the mode of Electricity-Orientated. Aiming at the optimization of economy, by comparing the wind power accommodation in two scenarios, it shows that P2G can effectively accommodate wind power, and that injecting natural gas generated by P2G into gas network by contract can reduce the uncertainty of gas network dispatching.

Wheel hollow wear of high-speed train is one of the main damage types for the wheel. By optimizing the vehicle and track parameters and matching the wheel-rail profile, the hollow wear of wheel can be reduced. In order to study the sensitivity of vehicle and track parameters to the wheel hollow wear, the sensitivity of suspension parameters and the track parameters of the CRH2Ctype high-speed train wheel on the hollow wear of the wheel was studied by the parameter sensitivity analysis method. The concept of the cumulative wear power dissipation was put forward. The distribution characteristics of the wheel hollow wear under the different wheel/rail treads matching were forecasted. The results show that the damping of antihunting motion damper of the vehicle is the most sensitive to the maximum cumulative wear power dissipation of the wheel, followed by the longitudinal stiffness of tumbler journal box node, lateral stiffness of air-spring suspension, vertical damping of primary suspension, vertical stiffness of track, and vertical damping of track. According to the analysis from the combination of sensitive parameters, the cumulative wear power dissipation is unevenly distributed in the lateral direction of the wheel tread and has the obvious peak area, which is basically the same as the actual wear distribution location in the field. The matching of the LMA wheel tread and the CN60N rail tread is a good choice to slow down the hollow wear and reduce the wheel wear rate. And the wheel reprofiling should be timely carried out, otherwise the wear rate would increase and the hollow wear would become more serious.

Because titanium alloy (Ti) has the natural advantage of a low elastic modulus, it has become the most commonly used material for the manufacturing of pedicle screws. However, its poor shear strength and osteogenic ability are undesirable properties. The superior osteoinductivity demonstrated by tantalum (Ta) in oral and maxillofacial surgery and joint surgery leads us to assume that the tantalum-coated pedicle screws may have better osteogenic properties and bone anchoring strength. To verify this hypothesis, MC3T3-E1 cells and human mesenchymal stem cells (hBMSCs) were seeded on the surface of Ta and Ti disks to compare the effects of two different metals on cell adhesion, proliferation, and differentiation. At the same time, we observed the inhibitory effect of Ta on osteoclasts. As an in vivo study, conventional Ti pedicle screws and Ta-coated screws were implanted in bilateral pedicles of Bama pigs. The results showed that compared to titanium, tantalum promoted greater cell adhesion and proliferation and improved the level of hBMSC mineralization, and Ta-coated screws exerted an inhibitory effect on osteoclasts. More importantly, we found that the effect of tantalum on osteogenic differentiation was mediated through the Wnt/β-catenin and TGF-β/smad signaling pathways. Ta-coated screws significantly promoted trabecular bone growth compared with Ti as evidenced by micro-CT, histology and biomechanical examination. Our study clearly indicated that tantalum was a superior promoter of osteogenesis and proved that tantalum coating is an effective improvement for titanium alloy implants.

To prevent damage of the China Railway Track System (CRTS) II slab track induced by thermal effects, post-installed reinforcement (PIR) bars between the prefabricated slabs and the concrete base have been utilized in the track. This work presents a study on the interfacial failure and arching of the CRTS II slab track reinforced by PIR bars due to the effects of temperature change. To this end, a novel finite element model of the track was established, in which the non-linear interfacial interaction between the track slabs and the cement asphalt (CA) mortar layer was simulated by a cohesive zone model, the non-linear constitutive material properties of track concrete were represented by a concrete damaged plasticity (CDP) model, and the non-linear bond-slip relationship between PIR bars and track concrete was characterized by non-linear spring elements. Comparison between simulation results and experimental data indicates that the proposed modelling technique is capable of evaluating the performance of the track reinforced by PIR bars. The combined action of insufficient bond strength between PIR bars and concrete, and insufficient bond strength between track slabs and CA mortar layer, was analyzed. Numerical analysis results show: (1) The temperature rise of interface failure between the concrete slabs and the CA mortar layer can be improved by 6 °C after PIR bars installation. (2) The PIR bars are effective in reducing arching displacement of slabs caused by temperature rise in both lateral direction and longitudinal direction of track slabs. (3) Both PIR bond strength and interface bond strength influence the maximum arching displacement of track slabs significantly.

A novel solar reflective fluorocarbon coating was proposed to improve the performance of ballastless tracks of high-speed railways at high temperature. Firstly, experiments were carried out to investigate the influence of the solar reflective fluorocarbon coating on the temperature field of coated concrete structures. Secondly, a non-linear finite element model of the ballastless track incorporating the non-linear properties of concrete and a cohesive zone relationship of interfaces between track components was established, and the numerical model was verified by on-site monitoring results. Then, based on the experimentally measured temperature fields, the efficiency of the solar reflective fluorocarbon coating on reducing temperature deformation of the track was quantified by finite element analysis, and the combined action of initial track component defects and bond properties between track components on the mechanical behavior of the coated track was analyzed. Finally, the influence of thermal performance of different coatings on mechanical behavior of the track was systematically investigated. Results show that the solar reflective fluorocarbon coating can reduce the surface temperature and the temperature gradient of the coated track by 10% and 14% respectively. After applying the solar reflective fluorocarbon coating to the ballastless track, the maximum slab end arching displacement, the rise of slabs in the lateral direction, and the maximum longitudinal stress of the concrete joints can be reduced by 20%, 19%, and 13% respectively. The combined action of initial track component defects and the interfacial bond strength should be considered when studying the thermal deformation of the ballastless track. Slab end arching displacements are mainly influenced by the surface temperature of the slabs.

This paper proposes a rail profile optimization method that takes account of wear rate within design cycle so as to minimize rail wear at the curve in heavy haul railway and extend the service life of rail. Taking rail wear rate as the object function, the vertical coordinate of rail profile at range optimization as independent variable, and the geometric characteristics and grinding depth of rail profile as constraint conditions, the support vector machine regression theory was used to fit the nonlinear relationship between rail profile and its wear rate. Then, the profile optimization model was built. Based on the optimization principle of genetic algorithm, the profile optimization model was solved to achieve the optimal rail profile. A multibody dynamics model was used to check the dynamic performance of carriage running on optimal rail profile. The result showed that the average relative error of support vector machine regression model remained less than 10% after a number of training processes. The dynamic performance of carriage running on optimized rail profile met the requirements on safety index and stability. The wear rate of optimized profile was lower than that of standard profile by 5.8%; the allowable carrying gross weight increased by 12.7%.

Study design Case report and review of relevant literature. Objective To report a rare complication of esophageal perforation in cervical fracture patient with progressive ankylosing spondylitis (AS) and review of relevant literature. Summary of background data Esophageal perforation in cervical fracture is extremely rare. This complication has never been reported in AS patients. Key points in the early diagnosis and management of this severe complication along with the cervical fracture were presented in detail in this case report. Methods A 61-year-old male with AS, who sustained C6 fracture and dislocation after a vehicle accident. Initial treatment strategy was combined anterior-posterior fixation and fusion. Although esophageal perforation in the dorsal wall of esophagus was detected in anterior surgery. After thorough debridement, the esophageal lesion was closed by resorbable interrupted sutures. Surgical incision was washed by saline and hydrogen peroxide without primary closure. Cervical fracture was treated by long level posterior fixation alone. After surgery, the anterior surgical incision was irrigated with normal saline twice a day and closed 3 weeks later. Results Esophageal perforation was healed completely and neurologic results were improved significantly after surgery. Union of the fracture and segmental stability of cervical spine was confirmed radiologically at 1-year follow up. Conclusion Esophageal perforation in cervical fracture patient with progressed AS is an extremely rare and potentially life-threatening complication. Surgical debridement and drainage with intensive care are essential for good outcome. Level of evidence 5.