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AimsThe optimal procedure for the treatment of ossification of the posterior longitudinal ligament (OPLL) remains controversial. The aim of this study was to compare the outcome of anterior cervical ossified posterior longitudinal ligament en bloc resection (ACOE) with posterior laminectomy and fusion with bone graft and internal fixation (PTLF) for the surgical management of patients with this condition.MethodsBetween July 2017 and July 2019, 40 patients with cervical OPLL were equally randomized to undergo surgery with an ACOE or a PTLF. The clinical and radiological results were compared between the two groups.ResultsThe Japanese Orthopaedic Association (JOA) score and recovery rate in the ACOE group were significantly higher than those in the PTLF group during two years postoperatively, provided that the canal occupying ratio (COR) was > 50%, or the K-line was negative. There was no significant difference in JOA scores and rate of recovery between the two groups in those in whom the COR was < 50%, or the K-line was positive. There was no significant difference in the Cobb angle between C2 and C7, sagittal vertical axis, cervical range of motion (ROM), and complications between the two groups.ConclusionCompared with PTLF, ACOE is a preferred surgical approach for the surgical management of patients with cervical OPLL in that it offers a better therapeutic outcome when the COR is > 50%, or the K-line is negative, and it also preserves better cervical curvature and sagittal balance. The prognosis of ACOE is similar to that of PTLE when the COR is < 50%, or the K-line is positive.Cite this article: Bone Joint J 2023;105-B(4):412–421.

Study design Western blot, reverse transcription-polymerase chain reaction (RT-PCR), radiological, and histological analyses of the rat ossification of ligamentum flavum (OLF) induced by cyclic tensile stress. Objective The aim of this study was to induce the OLF using cyclic tensile stress to rat thoracolumbar ligamentum flavum, and to investigate the possible molecular mechanism of tension-induced OLF. Summary of background data Tensile stress has been considered as an important factor leading to the OLF. So far, however, no OLF induced by tension has been reported. Methods Forty rats were randomly divided into five equal groups. For control groups, the blank and anesthesia groups were not subjected to tension. For experimental groups, the 4-, 8-, and 12-week groups were subjected to cyclic tensile stress of ligamentum flavum after abdominal anesthesia for 4 weeks, 8 weeks, and 12 weeks, respectively, using an original stress apparatus for rats. The radiological and morphological changes of rat spine, as well as the protein and mRNA expressions of CD44, bone morphogenetic protein-2 (BMP-2), integrin β3, collagen protein type I (COL1), osteopontin (OPN), runt-related transcription factor 2 (RUNX-2), and vascular endothelial growth factor (VEGF), were concerned. Results The micro-CT showed OLF in the 4-, 8-, and 12-week group. The axial maximum occupied area of ossifications was 1.42 mm2, 3.35 mm2, and 7.28 mm2, respectively. In histopathology, chondrocytes proliferated in the experimental model; woven bone arose in the 8- and 12-week groups, and was more noticeable in the 12-week group. According to western blot and RT-PCR, the expressions of seven osteogenesis-related molecules were all increased in three experimental groups. Conclusion Cyclic tensile stress to the ligamentum flavum in rats can induce the OLF, and the longer the duration, the more visible the osteogenesis. The upregulation and synergism of osteogenesis-related molecules may contribute to the OLF induced by tensile stress.Level of Evidence: N/A.

Acellular tendon matrix is an ideal substitute for constructing tissue engineering ligaments, but using detergents causes damage to collagen and fibrin during the process of decellularization. In this study, fresh tendons were lyophilized and separated into fresh tendon fiber (FTF) bundles, and then the cellular components in FTF were removed to prepare acellular tendon fiber (ATF) without adding chemical detergent. H&E staining and DAPI fluorescence microscopy showed no nucleus and DNA residue. Compared with FTFs, the DNA content of ATFs was significantly lower without the collagen content change before and after decellularization. The microstructure of collagen fibrils in ATFs was intact under scanning electron microscopy (SEM), and the maximum tensile load and elastic modulus between FTFs and ATFs were not statistically different. The ATF bundles were cultured with SD rat tenocytes for 72 hr and cells attachment to fiber surfaces were observed under SEM. ATF bundles were then implanted into paraspinal muscles, and histological analysis showed fibroblast-like cells within the ATFs and was similar to the control group (fresh tendon autograft) in morphology. H&E staining showed that the number of lymphocytes and plasma cells in ATF was less than that in fresh tendon autograft. ATF bundles were twisted into linear fiber materials by hand, of which the maximum breaking strength was similar to silk with same diameter. These findings demonstrated that ATFs retain their original fibril structure and mechanical properties after decellularization by trypsin and pancreatic deoxyribonuclease without detergent. Lyophilized ATFs linear fiber material provides the possibility of preparing personalized ligament and other tissue engineering scaffolds.

Background Ossification of the posterior longitudinal ligament (OPLL) is a disabling disease, of which the pathogenesis is still unclear, and there are no effective cure or prevention methods. Exosomal miRNA play an important role in osteogenesis of the ectopic bone. Therefore, we focused on the down-regulation miR-140-5p from OPLL cell-derived exosomes in order to explore the mechanism of exosomal miR-140-5p in inhibiting osteogenesis in OPLL. Results Exosomes were isolated by differential centrifugation and identified by transmission electron microscopy, nanoparticle tracking analysis, and exosomal markers. Exosomal RNA was extracted to perform miRNA sequencing and disclose the differentially expressed miRNAs, among which miR-140-5p was significantly down-regulated. The confocal microscopy was used to trace the exosomal miR-140-5p delivered from OPLL cells to human mesenchymal stem cells (hMSCs). In vitro, we verified exosomal miR-140-5p inhibited osteoblast differentiation of hMSCs by targeting IGF1R and suppressing the phosphorylation of IRS1/PI3K/Akt/mTOR pathway. In vivo, we verified that exosomal miR-140-5p inhibited the ectopic bone formation in mice assessed by micro-CT and immunohistochemistry. Conclusions We found that exosomal miR-140-5p could inhibit the osteogenic differentiation of hMSCs by targeting IGF1R and regulating the mTOR pathway, prompting a further potential means of drug treatment and a possible target for molecular therapy of OPLL.

To analyze the significance of ossification index of cervical posterior longitudinal ligament as a risk factor for thoracic OPLL (ossification of the posterior longitudinal ligament) in patients with cervical OPLL.We retrospectively analyzed the clinical data of cervical OPLL patients in Changzheng hospital, who received chest CT scans for screening of COVID-19, and included 87 patients into this study. According to the radiographic evidence, 87 patients were divided into CT group(cervical OPLL combined with thoracic OPLL）and C group(cervical OPLL group). We measured the cervical OS index (ossification index), and analyzed the relationship between thoracic OPLL and cervical OS index.There was no difference of age、sex、duration of symptoms、comorbidity between the 2 groups(P＞0.05). The mean cervical OS index was higher in the CT group than in the C group (8 ± 2 VS 3 ± 2，P＜0.001).Patients with cervical OS index ＞8 was considered as "high risk" of tandem OPLL, while with value ≤ 4 was considered as "low risk". Index between 5 and 8 were considered as "middle risk". This study demonstrated that the cervical OS index may be used as an indicator of thoracic OPLL in patients with cervical OPLL, with a high diagnostic accuracy.

The conductor temperature is a critical state variable that should be considered in power flow calculations to improve the calculation accuracy and reveal the potential thermal loadability of transmission components. This paper proposes a calculation method for time-process power flow considering the thermal behavior (TPPFCTB) of transmission components to calculate the temperature dynamics of overhead lines, power cables, and transformers under anticipated system operation scenarios. The TPPFCTB model is represented by differential-algebraic equations, which can be solved as a sequence of extended power flow problems at discretization time intervals. Based on the Newton method, incomplete and complete decoupling methods are proposed to decouple the correction equations into several independent groups with constant coefficient matrices, thus improving computational efficiency. The work presented in this paper provides an effective method for the detection of potential power transfer capability problems associated with transmission components, thus guiding operators to make more economical decisions. Numerical simulations were conducted to verify the effectiveness of the proposed method.

In recent years, machine learning (ML) techniques are proven to be powerful tools in various emerging applications. Traditionally, ML techniques are processed on general-purpose CPUs and GPUs, but their energy efficiencies are limited due to their excessive support for flexibility. As an efficient alternative to CPUs/GPUs, hardware accelerators are still limited as they often accommodate only a single ML technique (family). However, different problems may require different ML techniques, which implies that such accelerators may achieve poor learning accuracy or even be ineffective. In this paper, we present a polyvalent accelerator architecture integrated with multiple processing cores, called ParaML, which accommodates ten representative ML techniques, including $k$ -means, $k$ -nearest neighbors ( $k$ -NN), naive Bayes (NB), support vector machine (SVM), linear regression (LR), classification tree (CT), deep neural network (DNN), learning vector quantization (LVQ), parzen window (PW), and principal component analysis (PCA). Benefited from our thorough analysis on computational primitives and locality properties of different ML techniques, the single-core ParaML can perform up to 1056 GOP/s (e.g., additions and multiplications) in an area of 3.51 mm2 and consumes 596 mW only, estimated by ICC and PrimeTime PX with post-synthesis netlist, respectively. Compared with the NVIDIA K20M GPU (28-nm process), the single-core ParaML (65-nm process) is $1.21\times $ faster, and can reduce the energy by $137.93\times $ . We also compare the single-core ParaML with other accelerators. Compared with PRINS, single-core ParaML achieves $72.09\times $ and $2.57\times $ energy benefit for $k$ -NN and $k$ -means, respectively, and speeds up each query in $k$ -NN by $44.76\times $ . Compared with EIE, the single-core ParaML achieves $5.02\times $ speedup and $4.97\times $ energy benefit with $11.62\times $ less area when evaluating with dense DNN. Compared with TPU, the single-core ParaML achieves $2.45\times $ better power efficiency (5647 Gop/W versus 2300 Gop/W) with $321.36\times $ less area. Compared to the single-core version, the 8-core ParaML will further improve the speedup up to $3.98\times $ with an area of 13.44 mm2 and a power of 2036 mW.

To systematically review the clinical manifestations and treatment outcomes of patients with subaxial cervical spinal tuberculosis (SCS-TB) and evaluate the current evidence for surgical or nonsurgical treatment. A systematic review was performed using the PubMed, ScienceDirect, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) databases. Studies published in English from January 2000 to December 2018 were included in the search. A reference lists search of relevant articles was also conducted for other potential references. The risk of bias was assessed with the 13-item criteria recommended by the Cochrane Back and Neck Group and the Methodological Index for Non-Randomized Studies. Fifteen articles were included with a total of 456 patients, of which only 1 study was randomized and fourteen were nonrandomized. The most common symptom reported was neck pain and stiffness, and the most common segment involved was C5. Of the 456 patients, 329 (72.1%) were treated surgically. Most experienced neurologic recovery after surgery. Instrumentation resulted in maintenance of the correction of alignment throughout the follow-up period. The use of radical debridement is still in debate. Anti-TB therapy is necessary for all SCS-TB patients, including those underwent surgical management. For patients with neurological dysfunction, the surgical method with decompression and instrumentation could provide better cervical spinal alignment and stability. For adult, the radical debridement remains in debate, while for children, radical debridement may cause the development of progressive kyphosis during growth. Larger randomized comparative studies with longer follow-up times are needed.

To evaluate the clinical and radiographic results of cervical total disc replacement (CTDR) and anterior cervical discectomy and fusion (ACDF) in the treatment of single-level cervical disc degenerative disease with a mid-term follow-up period.Seventy-two patients with C5/6 single-level cervical degenerative disc disease refractory to conservative interventions were randomly assigned to two groups: ACDF and CTDR. Clinical outcomes were assessed by using the Japanese Orthopedic Association (JOA) score and the Neck Disability Index (NDI). Radiographic evaluations included range of motion (ROM), Cobb angles, heterotopic ossification (HO) and adjacent segment degeneration during follow-up.Sixty-nine patients (35 CTDR and 34 ACDF) were followed up over 4 years (mean 50.3 months). At 1 month postoperation, the NDI scores in CTDR patients were significantly higher than those in ACDF patients, especially in the work, driving and recreation aspects. There was significant improvement in global ROM in CTDR patients than in ACDF patients. The postoperative ROM of the C4/5 segment in ACDF patients increased significantly, and no significant difference was shown in other adjacent segments. The occurrence of HO was 42.9% (15/35) in the CTDR group at the last followup, with Grade I in 3 cases, Grade II in 11 cases and Grade III in 1 case.CTDR is an effective method in the treatment of single-level cervical disc degenerative disease. Compared to ACDF, CTDR is superior in the early improvement of quality of life, and restoration of segmental motion despite radiographic evidence of HO during a mid-term follow-up period.

To evaluate the effectiveness and safety of Qingjin Yiqi granules (QJYQ) on post-COVID-19 condition (PCC).Patients who met the inclusion criteria were randomly assigned to two groups, the QJYQ group received QJYQ combined with standard rehabilitation treatments (SRTs) and the control group only received SRTs. The treatment course was 14 days. The primary outcomes were modified Medical Research Council (mMRC) scale and Borg scale, while the secondary outcomes included symptoms score and 6-minute walking distance (6MWD). The safety outcome was the incidence of adverse events.A total of 388 patients with PCC were enrolled and randomly assigned to the QJYQ group (n = 194) and the control group (n = 194). Compared to the controls, the mMRC scale was improved in the QJYQ group, which was better than that of the control group [β (95%CI): -0.626 (-1.101, -0.151), p = 0.010]. A significant improvement in Borg scale was also observed in the QJYQ group compared to the control group [β (95%CI): -0.395(-0.744, -0.046), p = 0.026]. There was no statistically significant difference in symptoms score and 6MWD between the two groups (p = 0.293, p = 0.724). No treatment-related adverse events were observed in either group.QJYQ can bring benefits to patients with PCC, mainly in the improvement of breathlessness and fatigue.

Background: To analyze risk factors of titanium mesh cage (TMC) subsidence in single-level anterior cervical corpectomy and fusion (ACCF) for cervical ossification of the posterior longitudinal ligament (OPLL). Methods: Patients with cervical OPLL who were treated with single-level ACCF between January 2019 to December 2019 were retrospectively analyzed in two groups: patients with TMC subsidence as Group S, and patients with no TMC subsidence as Group N during the one-year follow-up period. The degree of distraction between decompression of the vertebral bodies and correction of the cervical curvature was measured to analyze their relationship with TMC subsidence. Results: There was no significant difference in patient demographics and complications between the two groups. The degree of distraction in Group S was significantly higher than that in Group N. The change of C2 to C7 Cobb angle (α) in Group S was significantly greater than that in Group N, and the interspinous process distance (SPD) in Group S was also significantly greater than that in Group N. The JOA score and JOA recovery rate were not statistically different between the two groups.Conclusions: Intraoperative selection of overlength TMC in single-level ACCF for OPLL, over-distraction, and excessive correction of the cervical curvature may cause TMC subsidence after surgery. No significant impact of TMC subsidence on the surgical outcome was observed during the 1-year follow-up period.

BackgroundThree-dimensional reduction plays a vital role in surgical reduction of irreversible atlantoaxial dislocation (IAAD). However, the most commonly used combination of C1 pedicle screw (PS) or lateral mass screw (LMS) and C2 PS or isthmus screw often fails to achieve satisfactory reduction at one time. The difficulty is usually caused by short anteroposterior and vertical distance between heads of C1 and C2 screws, which lack enough space for reduction operation. The objective of this study is to describe a three-dimensional reduction method with a modified C2 isthmus screw and to illustrate its advantage and effectiveness for IAAD.MethodsTwelve patients with IAAD underwent reduction and fixation with modified C2 isthmus screw combined with C1 PS or LMS, fusion with autologous bone graft. The insertion point was lateral to the intersection of caudal edge of C2 lamina and lateral mass, with a trajectory towards C2 isthmus, via lateral mass. The three-dimensional reduction was achieved through pulling and distracting. Radiographic evaluation included anteroposterior and direct distance between different insertion points, the occipitoaxial angle (O-C2A), clivus-canal angle (CCA) and cervicomedullary angle (CMA). Clinical outcomes evaluation included the Japanese Orthopaedic Association (JOA) score, Visual analog scale (VAS) and Neck Disability Index (NDI).ResultsAll the patients maintained effective reduction during the follow-up. The anteroposterior and direct distance was significantly higher in modified C2 isthmus screw than C2 PS whether combined with C1 PS or LMS (P ConclusionsThree-dimensional reduction method with a modified C2 isthmus screw is effective and safe in managing IAAD. It can increase the anteroposterior and vertical distance between the heads of C1 and C2 screws, which is benefit for the three-dimensional reduction operation of IAAD.

Continuous-valued deep convolutional networks (DNNs) can be converted into accurate rate-coding based spike neural networks (SNNs). However, the substantial computational and energy costs, which is caused by multiple spikes, limit their use in mobile and embedded applications. And recent works have shown that the newly emerged temporal-coding based SNNs converted from DNNs can reduce the computational load effectively. In this paper, we propose a novel method to convert DNNs to temporal-coding SNNs, called TDSNN. Combined with the characteristic of the leaky integrate-andfire (LIF) neural model, we put forward a new coding principle Reverse Coding and design a novel Ticking Neuron mechanism. According to our evaluation, our proposed method achieves 42% total operations reduction on average in large networks comparing with DNNs with no more than 0.5% accuracy loss. The evaluation shows that TDSNN may prove to be one of the key enablers to make the adoption of SNNs widespread.

Recent years, as deep learning rose in prominence, neural network accelerators boomed. The existing research shows that both speed and energy-efficiency can be improved by low precision data structure. However, decreasing the precision of data might compromise the usefulness and accuracy of the underlying AI. And the existing studies can not meet all AI application requirements. In the paper, we propose a new data type, called Float-Fix (FF). We introduce the structure of FF and compare it with other data types. In our evaluation, the accuracy loss of 8-bit FF is less than 0.12% on a subset of known neural network models, 7 $$\times $$ better than fixed-point, DFX and floating-point on average. We implement the hardware architectures of operators and neural processing unit using 8-bit FF data type with TSMC 65 nm Gplus High VT library. The experiments show that the hardware cost of convertors converting between 16-bit fixed-point and FF is really small. And the multiplier of 8-bit FF only needs 1188 $$\upmu \mathrm{m}^2$$ area, which is nearly 8-bit fixed-point. Comparing with the neural processing unit of DianNao, FF reduces 34.3% area.

Objective Single level ACCF combining single level ACDF (AcA) is an ideal way to treat CSM with multiple consecutive cervical intervertebral disc herniation alongside with severe bony narrowing of the spinal canal in between. AcA with the stand-alone technics on the ACDF level and a shorter titanium plate that only covers the ACCF levels (AcAsa) may possess potential advantages than conventional AcA. We performed a retrospective study to evaluate the feasibility, safety and effectiveness of AcAsa procedure. Methods 379 patients with CSM who had conventional AcA or AcAsa were retrospectively reviewed. Related patients factors, disease factors and treatment factors were acquired and subjected into student’s t test, chi-square test and survive analyses. Results Preoperative and postoperative JOA Scores in AcAsa: p

Background Ossification of the posterior longitudinal ligament (OPLL) is a 3-dimensional (3D) disease that causes cervical myelopathy. The conventional 2-dimensional (2D) measurement of OPLL has limitations in estimating cord compression and myelopathy. In this study, we attempted to use 3D computed tomography (CT) and magnetic resonance imaging (MRI) to measure the 3D occupying ratio of OPLL and investigate its significance in the assessment of spinal cord myelopathy. Methods Three-dimensional CT and MRI were performed in 50 patients with cervical OPLL at a neutral position before surgery. MRI was done to determine the extent of spinal cord compression. The CT data were saved in DICOM format and analyzed using Mimics 17.0. Then a 3D model of OPLL was semiautomatically segmented at a specific threshold. The following data were measured: diameter of the spinal canal, thickness of the OPLL, and 3D volume of the OPLL and spinal canal. The Japanese Orthopedic Association (JOA) score was used to assess the cervical spinal cord function. Results Pearson correlation analysis showed that both the occupying ratio and the 3D occupying ratio were significantly and negatively correlated with the JOA score. Multiple linear regression analysis indicated that only the 3D occupying ratio showed a significantly negative correlation with the JOA score, whereas age, sex, and the occupying ratio were insignificantly associated with the JOA score. Conclusions The 3D occupying ratio of OPLL is a reliable indicator for assessing the severity of spinal cord myelopathy. MRI provides more details about cord compression, making the measurement more accurate and objective.

// Yanqing Sun 1, * , Wei Zhu 1, * , Shengyuan Zhou 1 , Zhiwei Wang 1 , Xiongsheng Chen 1 and Lianshun Jia 1 1 Department of Spine, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China * These authors are considereds as co-first authors Correspondence to: Xiongsheng Chen, email: kkro3o4@yeah.net Lianshun Jia, email: owfndg@126.com Keywords: oxygen-glucose-serum deprivation/restoration, PC12, apoptosis, ischemia reperfusion Received: March 01, 2017 Accepted: August 06, 2017 Published: October 04, 2017 ABSTRACT Aims: To explicit cell apoptosis trend in PC12 oxygen-glucose-serum deprivation/restoration (OGSD/R) model and provide experimental bases for neural cell simulation in ischemia reperfusion injury in vitro . Methods: OGSD/R model was constructed using the passage PC12 cells in vitro . The profile of cell apoptosis was estimated by DAPI staining, Annexin V-FITC and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, as well as the levels of apoptosis-related proteins, including procaspase-3 and caspase-12. Results: PC12 apoptosis was induced by OGSD and aggravated after restoration. CCK8 assay indicated that cell activity reached minimum after 1h of oxygen-glucose-serum restoration (OGR). DAPI staining suggested that apoptosis was the most serious after 1h of OGR, causing apoptotic cell nucleus pyknosis, particle spot formation, and fracture of cells with serious apoptosis forming pieces, and nucleus disintegration. The percentage of apoptotic cells exhibited increased trend after restoration, and reached the highest at 1h of OGR. Moreover, the expression of procaspase-3 and caspase-12 were extremely enhanced after OGD, especially 1h after OGR. Conclusions: PC12 apoptosis is induced by OGSD and aggravated after restoration. The apoptosis of PC12 reaches the highest at 1h after OGR, which may provide experimental bases for spinal cord ischemia reperfusion injury treatment.

Thoracic ossification of the ligamentum flavum (TOLF) complicated with dural ossification (DO) is a severe clinical disease. The diagnosis of DO preoperatively remains challenging. The current study retrospectively analyzed imaging features of 102 segments with TOLF from 39 patients and proposed a grading system for evaluating DO risk. Logistic regression results showed that unilateral spinal canal occupational rate (UCOR), tram track signs, and C-signs were all risk factors for DO (odds ratios of 5.393, 19.734 and 72.594, respectively). In validation analyses for the TOLF-DO grading system, sensitivity was 76.0% (19/25), specificity was 91.0% (70/77), and Youden’s index was 0.66. Thus, implementation of the TOLF-DO grading system has the potential to improve the diagnosis of DO.

Study design Retrospective study. Objective To determine the optimal open side in unilateral open-door laminoplasty (UODL) for lateral cervical ossification of posterior longitudinal ligament (OPLL). Summary of background data No literature has reported which side of the vertebral arch should be chosen as the open side in UODL for lateral cervical OPLL. Methods Patients with lateral cervical OPLL who were treated with UODL between 2013 and 2018 were retrospectively analyzed in two groups: Group A, where the open side was contralateral to the ectopic bone, and Group B, where the open side was ipsilateral to the ectopic bone. The Japanese Orthopaedic Association (JOA) Score, JOA recovery rate, spinal canal enlargement rate, cervical range of motion (ROM), and spinal cord area (SCA) were measured to evaluate and compare the clinical outcomes between the two groups. Statistical analysis was performed by t test and Hotelling T2 test. Results There was no significant difference in patient demographics and major complications between the two groups. The postoperative JOA Score and JOA recovery rate in Group A were significantly higher than those in Group B. There was no significant difference in cervical ROM within or between the two groups during the 2-year follow-up period, nor was there significant difference in spinal canal enlargement between the two groups. However, both postoperative SCA and increased SCA in Group A were significantly higher than those in Group B. Conclusion The contralateral open side approach is preferable to the ipsilateral open side approach in UODL for lateral cervical OPLL. Level of evidence 3.

Background Cervical ossification of the posterior longitudinal ligament (OPLL) is a kind of spinal disorder widely spared in Asia. In dealing with multilevel cervical OPLL, the ideal surgical approach is still under debate. Here we introduce our findings of multilevel anterior cervical corpectomy and fusion (ACCF) in treating multilevel cervical OPLLMethods 79 patients with multilevel cervical OPLL who had ACOR on C4-C5 or C5-C6 were retrospectively reviewed. Patients’ Japanese Orthopedic Association (JOA) Score, the improvement rate of JOA Scores (RIS), sagittal cervical mobility (SCM) and the distance between the lower endplate of the vertebra body above the titanium mesh and the superior endplate of the vertebra body below the titanium mesh ( L ) were analyzed and subjected into paired-t test. Radiographic features and complications were described as well.Results p

Bone defects remains a challenge for surgeons. Bone graft scaffold can fill the defect and enhance the bone regeneration. Demineralized bone matrix (DBM) is an allogeneic bone graft substitute, which can only be used as a filling material rather than a structural bone graft. Coating of the scaffolds with nanoscale DBM may enhance the osteoinductivity or osteoconductivity. Herein the lyophilization method is presented to coat the nano-DBM on surface of the porous polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP) scaffolds fabricated by 3D printing technology. The morphology, elastic modulus, in vitro cell biocompatibility, and in vivo performance are investigated. Scanning electron microscope (SEM) shows DBM particle clusters with size of 200-500 nm are observed on scaffolds fibers after coating. MC3T3-E1 cells on nano-DBM coated PCL/β-TCP scaffold show better activity than on PCL/β-TCP scaffold. In vivo tests show better infiltration of new bone tissue in nano-DBM coated PCL/β-TCP scaffold than PCL/β-TCP scaffold via the interface. These results show the presence of nano-DBM coating on PCL/β-TCP scaffold could enhance the attachment, proliferation, and viability of cells and benefit for the new bone formation surrounding and deep inside the scaffolds. Nano-DBM could potentially be used as a new kind of biomaterial for bone defect treatment.

Power cable is an important transmission component in distribution systems. The full utilization of the cable's transfer capability is of great significance to improve the economic and security performances of distribution systems. In this paper, a calculation method for electrothermal coupling (ETC) power flow for cable-based distribution systems is developed by embedding the solution of the thermal model of the crosslinked polyethylene (XLPE) insulated cable into the forward-backward sweep power flow calculation process of distribution systems. The method can be used to calculate the temperature dynamics of 3-phase cables under anticipated operation scenarios of distribution systems, thus revealing the potential transfer capability exists in the thermal inertia process of cable lines to operators. In case studies, the validity of the proposed ETC power flow calculation method is verified. Besides, the influence of the temperature of cable conductors on power flow is analyzed and the benefits of implementing the ETC power flow for the cable-based distribution systems are also illustrated.

The research on thermal protective clothing aims to reveal the heat transfer law inside the thermal protective fabric, and provide scientific reference for the research and development of thermal protective clothing, which is of great significance for reducing the skin damage of workers in high temperature environment. In this paper, the heat transfer model of “thermal protective clothing-air layer-skin” system is established according to the thermal conduction mechanism of heat. The finite difference method is used to classify the heat conduction partial differential equations by time and space, discretize them into classical implicit format, and then iterate. The method obtains the numerical solution of the equation and obtains the obtained temperature distribution in the form of a matrix and a three-dimensional image.

Randomness, intermittence and fluctuation are features of new energy, which includes wind energy, and the prediction of wind farm output power is of great significance to the operation of power systems connected with a large amount of wind power. A neural network prediction algorithm was proposed for wind farm power generation, and wavelet theory is used to optimize the prediction model to improve the prediction lag problem.

Deep neural networks (DNNs) have been considered to be the state-of-the-art artificial intelligence methods in a very broad range of applications. However, DNNs are compute intensive and memory intensive which are difficult to be employed in practical scenarios. Due to their favorable parallel computing ability, a series of DNN accelerators have been proposed. However, the improvement of on-chip computing capacity and the increasing number of parameters in the neural networks make access to memory a bottleneck. In this paper, we analyze the existing DNN algorithms. We observe that the special structure of neural networks makes it have two useful characteristics, which are unilateral directivity and local independence. Based on these characteristics, we propose a general software scheduling method to reduce memory access cost. Based on the experimental results, our method can reduce 32% memory access cost and achieve a speedup of 1.6x in average on our experiment platform and the best result is in ResNet-50, which is up to 56% and 2.62x.

Objective To investigate the incidence, distribution characteristics, and radiographic features of the ossification of the posterior longitudinal ligament (OPLL) combined with ossification of the nuchal ligament (ONL) and to analyze the correlation between the location of ONL and degree of ossification in patients with cervical OPLL. Methods From January 2010 to December 2016, the clinical data of 217 patients with cervical OPLL were reviewed retrospectively. Type and location of OPLL and ONL were determined on computed tomography images and lateral radiograph films. For patients with the local type of ONL, the segment with the largest spinal canal occupation ratio (COR) of OPLL was determined on cross-sectional computed tomography slices. The correlation between the location of ONL and segment with the largest COR of OPLL was evaluated. Results Of the 217 patients with cervical OPLL, 118 patients (54.4%) had OPLL combined with ONL (92 male and 26 female patients). The incidence of ONL was almost 1.4 times greater in males than in female patients (P = 0.03). C5–C6 (49.5%) was the segment at which ONL occurred most. Of 60 patients with the local type of ONL, 34 patients' ONL was located at the segment with largest COR of OPLL. The matching ratio was the largest (77.8%) when the type of OPLL was locally circumscribed (P = 0.003). Conclusions The incidence of ONL was 54.4% in patients with cervical OPLL, and male patients were affected more than female patients. ONL occurred most in segment C5–C6. The location of local-type ONL commonly corresponded to the segment with the largest COR of OPLL when type of OPLL was circumscribed.

Background: Severe neurologic deficit caused by cervical ossification of the posterior longitudinal ligament (COPLL) requires surgical treatment. However, the surgical strategies to treat cervical myelopathy caused by COPLL remains controversial. We aimed to determine the efficacy and advantages of en bloc resection of posterior vertebral wall and ossified mass in the treatment of COPLL. Methods: This is a retrospective case series. From July 2009 to June 2016, ninety-one COPLL patients underwent surgical treatment at the spine center of Shanghai Changzheng Hospital in China. Among them, forty-eight patients underwent anterior cervical ossified mass of posterior longitudinal ligament piecemeal resection (ACOP) by small Kerrison punch (from July 2009 to December 2013), and forty-three patients underwent anterior cervical ossified posterior longitudinal ligament en bloc resection (ACOE) by a burr-grinding technique (from January 2014 to June 2016). The canal occupational rates (CORs) of ossification in ACOP group were50-59% in 24 cases, 60-69% in 17 cases and ≥ 70% in 7 cases; in ACOE group, the CORs of ossification present as follows: 50-59% in 21 cases, 60-69% in 13 cases and ≥ 70% in 9 cases. In ACOP group the ossified masses were piecemeal resected and in ACOE group the ossified mass and the posterior vertebral wall were en bloc resected. All ossified dura maters in the two groups were removed if present, and arachnoids were covered with biological membranes. The Japanese orthopedic association (JOA) system was used to evaluate the neurologic outcomes of the two groups. X-rays were used to examine the positions of the internal fixations, and CT scans were used to evaluate the scopes of the ossification excision, and MRIs were implemented to evaluate the decompression situations of the spinal nerve. Findings: At the last follow-up visit for 24-90 months (35.1±6.4 months), the JOA scores all improved at postoperative three months, one year and the last follow-up in two groups. At the time of pre-operation, one year postoperative and the last follow-up, there was no significant difference in JOA scores of single-vertebral resection and double-vertebral resection between the two group. While at three months postoperative, the JOA scores of single-vertebral resection and double-vertebral resection in ACOE group were both higher than which in ACOP group. In terms of complications in ACOE group, intraspinal hematoma was not identified, cerebrospinal fluid leakage (CSFL) in one case, C5 root palsy in one case, internal fixation loosening in one case, hoarseness in one case and Horner syndrome in one case; in ACOP group, internal fixation loosening was not identified, CSFLs in 6 cases, C5 root palsy in two cases, hoarseness in four cases, intraspinal hematoma in one case and Horner syndrome in two cases. All complications were effectively recovered. No postoperative aggravation of neurological dysfunction and wound infection occurred. Comparing to ACOP, the ACOE is more efficient and safer with better neurological improvement in a short time follow-up (