Minimally invasive surgeries, including posterior endoscopic cervical foraminotomy (PECF), microsurgical anterior cervical foraminotomy (MACF), anterior transdiscal approach of endoscopic cervical ...discectomy (ATd-ECD), and anterior transcorporeal approach of endoscopic cervical discectomy (ATc-ECD), have obtained positive results for cervical spondylotic radiculopathy. Nonetheless, there is a lack of comparison among them regarding their biomechanical performance. The purpose of this study is to investigate the biomechanical changes of operated and adjacent segments after minimally invasive surgeries compared to a normal cervical spine. A three-dimensional model of normal cervical vertebrae C3-C7 was established using finite element analysis. Afterwards, four surgical models (PECF, MACF, ATd-ECD, and ATc-ECD) were constructed on the basis of the normal model. Identical load conditions were applied to simulate flexion, extension, lateral bending, and axial rotation of the cervical spine. We calculated the range of motion (ROM), intradiscal pressure (IDP), annulus fibrosus pressure (AFP), uncovertebral joints contact pressure (CPRESS), and facet joints CPRESS under different motions. For all circumstances, ATc-ECD was close to the normal cervical spine model, whereas ATd-ECD significantly increased ROM and joints CPRESS and decreased IDP in the operated segment. PECF increased more the operated segment ROM than did the MACF, but the MACF obtained maximum IDP and AFP. Except for ATc-ECD, the other models increased joints CPRESS of the operated segment. For adjacent segments, ROM, IDP, and joints CPRESS showed a downward trend in all models. All models showed good biomechanical stability. With their combination biomechanics, safety, and conditions of application, PECF and ATc-ECD could be appropriate choices for cervical spondylotic radiculopathy.
Searchable encryption scheme allows users to search for encrypted data containing some keywords without decrypting data. It protects the data privacy of data owners while promoting efficient data ...access. The searchable encryption scheme only supports a single keyword, which is easy to cause the problem of data redundancy. It makes users have to filter again in a large amount of data. In order to achieve the search goal more accurately, researchers proposed multi-keyword searchable encryption scheme. In addition, searchable encryption schemes that only support a single keyword are vulnerable to the disclosure of user access and search pattern. Based on these two reasons, we propose a searchable encryption scheme based on multi- keyword, which supports users to input more complex retrieval requests, and users can get a better sense of search experience. At the same time, it reduces the possibility of leakage of user access and search pattern to a certain extent. We also define the security model and prove that the scheme can resist the internal keyword guessing attack under the standard model. Finally, we also compare theoretical performance with other schemes and evaluate the experimental performance of our scheme.
•We propose a searchable encryption scheme based on multi -keyword, which supports users to input more complex retrieval requests.•We also define the security model and prove that the scheme can resist the internal keyword guessing attack under the standard model.•We compare theoretical performance with other schemes.
Outsourcing data to cloud services is a good solution for users with limited computing resources. Privacy and confidentiality of data is jeopardized when data is transferred and shared in the cloud. ...The development of searchable cryptography offers the possibility to solve these problems. Symmetric searchable encryption (SSE) is popular among researchers because it is efficient and secure. SSE often requires the data sender and data receiver to use the same key to generate key ciphertext and trapdoor, which will obviously cause the problem of key management. Searchable encryption based on public key can simplify the key management problem. A public key encryption scheme with keyword search (PEKS) allows multiple senders to encrypt keywords under the receiver’s public key. It is vulnerable to keyword guessing attacks (KGA) due to the small size of the keywords. The proposal of public key authenticated encryption with keyword search (PAEKS) is mainly to resist inside keyword guessing attacks. The previous security models do not involve the indistinguishability of the same keywords (w0××=w1), which brings the user’s search pattern easy to leak. The essential reason is that the trapdoor generation algorithm is deterministic. At the same time, most of the existing schemes use bilinear pair design, which greatly reduces the efficiency of the scheme. To address these problems, the paper introduces an improved PAEKS model. We design a lightweight public key authentication encryption scheme based on the Diffie-Hellman protocol. Then, we prove the ciphertext indistinguishability security and trapdoor indistinguishability security of the scheme in the improved security model. Finally, the paper demonstrates its comparable security and computational efficiency by comparing it with previous PAEKS schemes. Meanwhile, we conduct an experimental evaluation based on the cryptographic library. Experimental results show that the computational overhead of our scheme compared with the ciphertext generation algorithm, trapdoor generation algorithm and test algorithm of other schemes Our scheme reduces 274, 158 and 60 times, respectively.
Cloud computing can provide users with sufficient computing resources, storage, and bandwidth to meet their needs. Data security and privacy protection are among the new threats faced by users. ...Searchable encryption is the combination of search technology and encryption technology. Searchable encryption can upload the user’s data to the cloud server after special encryption, and can realize the function of retrieving according to keywords. Comparatively to symmetric searchable encryption (SSE), public key searchable encryption (PEKS) simplifies key management greatly. However, most existing public key authenticated encryption with keyword search (PAEKS) schemes are based bilinear pairing, making them computationally expensive. Apart from this, complex retrieval requirements and the integrity of the results had not been considered. To address these problems, we propose a blockchain-based PAEKS schemes supporting multi-keyword queries and integrity verification. In addition, we provide security proofs for the PAEKS scheme under the decisional oracle Diffie-Hellman (DODH) assumption. This scheme a scheme that requires less storage and computational power than other schemes of the same kind.
Spinal cord injury (SCI) treatment represents a major challenge in clinical practice. In recent years, the rapid development of neural tissue engineering technology has provided a new therapeutic ...approach for spinal cord injury repair. Implanting functionalized electroconductive hydrogels (ECH) in the injury area has been shown to promote axonal regeneration and facilitate the generation of neuronal circuits by reshaping the microenvironment of SCI. ECH not only facilitate intercellular electrical signaling but, when combined with electrical stimulation, enable the transmission of electrical signals to electroactive tissue and activate bioelectric signaling pathways, thereby promoting neural tissue repair. Therefore, the implantation of ECH into damaged tissues can effectively restore physiological functions related to electrical conduction. This article focuses on the dynamic pathophysiological changes in the SCI microenvironment and discusses the mechanisms of electrical stimulation/signal in the process of SCI repair. By examining electrical activity during nerve repair, we provide insights into the mechanisms behind electrical stimulation and signaling during SCI repair. We classify conductive biomaterials, and offer an overview of the current applications and research progress of conductive hydrogels in spinal cord repair and regeneration, aiming to provide a reference for future explorations and developments in spinal cord regeneration strategies.
•The microstructure and performance of Co-based layer with different Ni/WC contents were analyzed.•Nickel-coated WC was used to reduce the decomposition of WC during laser cladding.•The microhardness ...of Co-based layer increased with increasing Ni/WC content.•The wear resistance of Co-based layer increased with increasing Ni/WC content.
Fe-Co duplex coating has been deposited onto crystallizer copper plates surface by Nd: YAG laser cladding. To further improve the wear resistance of the duplex coating, the effects of various nickel-coated WC (Ni/WC) contents on the microstructural characterization and wear properties of different coatings have been investigated by using optical microscopy (OM), X-ray diffractometer (XRD), scanning electron microscope (SEM) and energy disperse spectroscope (EDS). The experimental results indicated that the microstructures of the Co-based layer were mainly composed of dendrite and eutectic structure, which were refined with increasing Ni/WC content. Compared with the Co-based layer without Ni/WC, the addition of Ni/WC facilitated the formation of new phase Co3W9C4 and WC. Moreover, the decomposition of WC particles on the Co-based layer enhanced the effect of solid solution strengthening, resulting in an improvement of the microhardness and wear resistance of the working layer. Based on the obtained results, the incorporation of Ni/WC was an attainable way to improve the tribological properties of Co-based alloy coatings.
In order to achieve the automatic planning of power transmission lines, a key step is to precisely recognize the feature information of remote sensing images. Considering that the feature information ...has different depths and the feature distribution is not uniform, a semantic segmentation method based on a new AS-Unet++ is proposed in this paper. First, the atrous spatial pyramid pooling (ASPP) and the squeeze-and-excitation (SE) module are added to traditional Unet, such that the sensing field can be expanded and the important features can be enhanced, which is called AS-Unet. Second, an AS-Unet++ structure is built by using different layers of AS-Unet, such that the feature extraction parts of each layer of AS-Unet are stacked together. Compared with Unet, the proposed AS-Unet++ automatically learns features at different depths and determines a depth with optimal performance. Once the optimal number of network layers is determined, the excess layers can be pruned, which will greatly reduce the number of trained parameters. The experimental results show that the overall recognition accuracy of AS-Unet++ is significantly improved compared to Unet.
Abstract Background: Although the treatment of peripheral T-cell lymphoma (PTCL) has undergone advancements during the past several years, the response rate and long-term effects with respect to ...patients with PTCL remain unsatisfactory—particularly for relapsed or refractory (R/R) patients. This phase II trial was designed to explore the efficacy and safety of an all-oral regimen of chidamide plus prednisone, cyclophosphamide, and thalidomide (CPCT) for R/R PTCL patients who could not tolerate the standard chemotherapy for a variety of reasons. Methods: We conducted a multicenter phase II clinical trial in which we combined chidamide (30 mg twice weekly) with prednisone (20 mg daily after breakfast), cyclophosphamide (50 mg daily after lunch), and thalidomide (100 mg daily at bedtime) (the CPCT regimen) for a total of fewer than 12 cycles as an induction-combined treatment period, and then applied chidamide as single-drug maintenance. Forty-five patients were ultimately enrolled from August 2016 to April 2021 with respect to Chinese patients at nine centers. Our primary objective was to assess the overall response rate (ORR) after the treatment with CPCT. Results: Of the 45 enrolled patients, the optimal ORR and complete response (CR)/CR unconfirmed (CRu) were 71.1% (32/45) and 28.9% (13/45), respectively, and after a median follow-up period of 56 months, the median progression-free survival (PFS) and overall survival (OS) were 8.5 months and 17.2 months, respectively. The five-year PFS and OS rates were 21.2% (95% confidence interval CI, 7.9–34.5%) and 43.8% (95% CI, 28.3–59.3%), respectively. The most common adverse event was neutropenia (20/45, 44.4%), but we observed no treatment-related death. Conclusion: The all-oral CPCT regimen was an effective and safe regimen for R/R PTCL patients who could not tolerate standard chemotherapy for various reasons. Trial Registration: ClinicalTrials.gov, NCT02879526.
With the development of the petrochemical industry, pipeline inspection technology plays a vital role in terms of avoiding explosions and protecting people's life and property. Pipelines working in ...high-temperature environments suffer from dual dangers of internal and external wall defects. It is often difficult to find a single nondestructive testing (NDT) method that can cover internal and external defects detection especially in high-temperature environments. In order to discover pipeline defects in time, we propose a hybrid online monitoring method for comprehensive defects inspection in high-temperature environments. This hybrid monitoring method combines eddy current testing (ECT) with electromagnetic acoustic transducer (EMAT) techniques. Specifically, we split the coil signal into two channels; one channel gives ECT signal and the other gives EMAT signal; furthermore, we demonstrate the feasibility of the proposed hybrid monitoring method by numerical simulations and laboratory experiments. The results show that the proposed hybrid online monitoring method can be used successfully to simultaneously monitor surface and internal defects and has high stability even at temperatures above 300 °C. Our approach achieves the genuine integration of ECT/EMAT technologies, effectively addressing the challenge of incomplete monitoring of pipeline defects in high-temperature environments.
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