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This paper constructs a network security intelligence analysis model based on deep learning methods. Firstly, the weights and thresholds of network packets are modeled using the convolutional neural network algorithm to extract the main information features. Then, the backward propagation algorithm is used for layer-by-layer propagation, combined with an unsupervised autoencoder to achieve the network parameter update. The results show that the model can recognize a variety of network viruses, with an average detection rate of 97%, and the error rate is kept around 0.5%. The network security intelligence analysis model is based on the deep learning method to analyze and warn about network intrusion data, effectively improving college students’ awareness about network security.

Low-temperature plasma ablation has been recently used for minimally invasive surgeries. However, more research is still needed on its generation process during tissue ablation and the underlying mechanism of tissue thermal damage. In this paper, high-speed camera footage, voltage–current signal collection, temperature analysis, and histological analysis were used to investigate the dynamic process of plasma tissue ablation and its thermal effect of dual-needle electrodes immersed in normal saline, which were driven by a high-frequency DC power supply with an output voltage ranging from 220 V to 320 V and a squire wave of 100 kHz. Microbubbles occurred around the ground electrode and merged to form a vapor layer that could completely cover the ground electrode. Plasma capable of ablating tissue would occur in the vapor layer between the ground electrode and tissue. The effect of electrical parameters on plasma generation and its thermal effect are analyzed by statistical results. The experimental results indicated that the voltage applied to the electrodes significantly influenced both the generation and stability of plasma, as well as the heat generation and tissue damage around the electrodes. Furthermore, under the same voltage, the existence of biological tissue promotes the formation of a vapor layer around the electrode, thereby facilitating the generation and stability of plasma. Notably, the temperature rise around the ground electrode is much higher than that around the powered electrode. These results have direct application to the design of plasma tissue ablation systems, which could achieve tissue ablation effects with minimal thermal damage. [ABSTRACT FROM AUTHOR]

This study aimed to design a novel electrode for reducing tissue thermal damage in radiofrequency-induced intestinal anastomosis. We developed and compared two electrodes (Ring electrode, and Plum electrode with reduced section of the middle fusion area by nearly 80% arising from novel structural design) by performing ex-vivo experiments and finite element analysis. In contrast to the Ring electrode group, slightly higher mean strength is acquired with the tensile force and burst pressure results increasing from 9.7 ± 1.47 N, 84.0 ± 5.99 mmHg to 11.1 ± 1.71 N, 89.4 ± 6.60 mmHg, respectively, as well as a significant reduction in tissue thermal damage for the Plum electrode group, with compression pressure of 20 kPa, RF energy of 120 W and welding duration of 8 s applied to the target regions to achieve anastomosis. Besides, the novel structural design of the Plum electrode can counteract the tension generated by intestinal peristalsis and enhance the biomechanical strength of the anastomotic area. The histological observation showed that the fusion area of the two-layer intestinal tissue is tightly connected with decreased thickness. The novel electrode (Plum electrode) could reduce tissue thermal damage in radiofrequency-induced intestinal anastomosis. [ABSTRACT FROM AUTHOR]

The mechanical properties of the stent graft are important factors influencing the outcome of TEVAR treatment and the occurrence of postoperative complications. The aim of this study is to improve and design a mechanical performance testing equipment for thoracic aortic stent grafts. The mechanical performance testing equipment consists of a radial force testing equipment of the stent graft designed by the wire compression grip method and a dynamic straightening force testing device with stable and controllable test conditions and continuously variable test angles. By constructing the testing equipment to physically measure the stent specimen, the experimental results reflect the trend of change and the simulation results are basically consistent, i.e. the mechanical properties of the thoracic aortic stent designed in this study is feasible and the measured data are valid. The testing equipment can provide the basis and reference direction for the quality testing of stent graft products, optimisation of mechanical properties of stent grafts and R&D innovation. [ABSTRACT FROM AUTHOR]

For decades, radiofrequency (RF)-induced tissue fusion has garnered great attention due to its potential to replace sutures and staples for anastomosis of tissue reconstruction. However, the complexities of achieving high bonding strength and reducing excessive thermal damage present substantial limitations of existing fusion devices. This study proposed a discrete linkage-type electrode to carry out ex vivo RF-induced intestinal anastomosis experiments. The anastomotic strength was examined by burst pressure and shear strength test. The degree of thermal damage was monitored through an infrared thermal imager. And the anastomotic stoma fused by the electrode was further investigated through histopathological and ultrastructural observation. The burst pressure and shear strength of anastomotic tissue can reach 62.2 ± 3.08 mmHg and 8.73 ± 1.11N, respectively, when the pressure, power and duration are 995 kPa, 160 W and 13 s, and the thermal damage can be controlled within limits. Histopathological and ultrastructural observation indicate that an intact and fully fused stomas with collagenic crosslink can be formed. The discrete linkage-type electrode presents favorable efficiency and security in RF-induced tissue fusion, and these results are informative to the design of electrosurgical medical devices with controllable pressure and energy delivery. [ABSTRACT FROM AUTHOR]

At present, most searchable encryption focuses on text search, aiming at how to search graphics in cloud computing, a new privacy preserving searchable encryption scheme under public key system is proposed. Through a new similarity judgment technique, the characteristic information of graphic shape is transformed into single keyword encryption, and the graphic shape searchable encryption (GSSE) is realized by using the public key authentication encryption with keyword searchable (PAEKS), which realizes the function of protecting the privacy of users and data, and the fixed size ciphertext and trapdoor are achieved. Finally, under the random oracle model, it is proved that the scheme proposed in this paper has the semantic security of external selection multi-keyword attack and internal keyword guessing attack. Finally, under the random oracle model, the semantic security of external selection multi- keyword attack and internal keyword guessing attack of the scheme is proved. The experimental results show that the scheme has high efficiency. [ABSTRACT FROM AUTHOR]

This paper presents the failure analysis of the crack and leakage accident of a crude oil pipeline under CO2-steam flooding in the western oilfield of China. To analyze the failure behavior and cause, different testing, including nondestructive testing, chemical composition analysis, tensile property testing, metallographic analysis, and microanalysis of fracture and chloride stress corrosion cracking (SCC) testing, are applied in the present study. The obtained results showed that the pipeline under the insulation layer of high humidity, high oxygen content, and high Cl− environment occurred pit corrosion, and the stress concentration area at the bottom of the corrosion pit sprouted cracks. Besides, it is demonstrated that the cracks were much branched, mostly through the crystal, and the fracture showed brittle, which is consistent with the typical characteristics of chloride SCC. Meanwhile, the insufficient Ni content of the pipeline material promoted the process of chloride SCC, and the high-temperature working conditions also aggravated the rate of chloride SCC. In addition, efficient precautions were provided to avoid fracture. [ABSTRACT FROM AUTHOR]

Radiofrequency (RF)-induced tissue fusion shows great potential in sealing intestinal tissue without foreign materials. To improve the performance of RF-induced tissue fusion, a novel self-cooling jaw has been designed to minimize thermal damage during the fusion. The prototype of self-cooling jaws was developed and manufactured. A total number of 60 mucosa-to-mucosa fusions were conducted using ex-vivo porcine intestinal segments with the proposed design and conventional bipolar jaws. The effects of intestinal fusion were evaluated based on temperature curves, burst pressure, thermal damage, and histological appearances. The self-cooling jaws showed significant decrease in temperature during the fusion process. An optimal burst pressure (5.7 ± 0.5 kPa) and thermal damage range (0.9 ± 0.1 mm) were observed when the applied RF power was 100 W. The thermal damage range of the prototype has almost decreased 36% in comparison with the conventional bipolar jaws (1.4 ± 0.1 mm). The histological observation revealed that a decrease of thermal damage was achieved through the application of self-cooling jaws. The self-cooling jaws were proved to be effective for reducing the thermal damage during RF-induced tissue fusion, which could potentially promote the clinical application of tissue fusion techniques in the future. [ABSTRACT FROM AUTHOR]

Purpose: The mechanism of chemo‐resistance in small cell lung cancer (SCLC) is unclear. This study aims to explore the resistance‐related genomic profiles of residual tumors after neo‐adjuvant chemotherapy (NAC) in SCLC through the whole‐exome sequencing (WES). Experimental design A total of 416 limited diseases (LD) SCLC patients underwent surgery were retrospectively analyzed, of which 40 patients received NAC. Then we selected 29 patients undergoing NAC (n = 19) and chemotherapy naïve (CTN, n = 10) to perform WES sequence with formalin‐fixed paraffin‐embedded samples including tumor and paired para‐tumor. Results: In total, single nucleotide variation and mutation rate were similar between NAC and CTN groups. The mutation signatures were significantly discrepant between NAC and CTN groups, as well as among patients with partial response (PR), stable disease (SD), and progressive disease. There were more copy number variation deletions in NAC group compared with CTN group. The inactivation of TP53 and RB1 were the most significantly events in both NAC and CTN groups. RB1 nonsense mutations were recurrent in NAC group (9/19 vs. 0/9, 47.4% vs. 0%) with favorable survival, while the frame‐shift deletions were frequent in CTN group (3/9 vs. 3/19, 33.3% vs.15.8%). Integrated function enrichment revealed that the frequently mutant genes were involved in cell cycle, metabolic reprogramming, and oncogenic signaling pathways in NAC group, such as BTG2 pathway, glycolysis in senescence and P53 pathway. A total of 27 genes presented frequently mutant in NAC group and might played a positive role in drug resistance. Multiple genes including BRINP3, MYH6, ST18, and PCHD15, which were associated with prognosis, occurred mutant frequently in PR and SD groups. Conclusion: Residual tumors after neo‐adjuvant therapy exhibited different mutation signature spectrum. Multiple genes including RB1 nonsense mutations, BRINP3, MYH6, ST18, and PCHD15 were with frequent mutation in residual tumors, which might participate chemo‐resistance and influenced the prognosis in patients with limited disease SCLC. [ABSTRACT FROM AUTHOR]

This paper reports the design of a powered stapler for gastrointestinal anastomosis and evaluates its performance. The proposed stapling instrument is intended to simplify and optimize the current procedure of mechanical stapling, while providing controllable operation for the powered stapling procedure, such as conditioning the tissue to the right stage before firing of the stapler. The feasibility and efficacy of the prototype were assessed by ex vivo experiments with porcine small intestine segments, where the tissue conditioning operation, burst pressure of the stapled intestine samples, and staple malformation rate were examined. The functionality of the developed powered stapler was validated, where the theoretical, numerical, and experimental results agree well with each other. The preliminary results indicated that the proposed tissue conditioning operation could lower the clamping pressure with a maximum level of 1.35 g/mm2. The average burst pressure of the stapled segments (16 samples) is 6.37 kPa, and the maximum malformation rate of the tested groups (five groups, each group with 90 staplers) was 5.56%. The developed novel tissue conditioning procedure could reduce the pressure response of the intestine tissue samples. The proposed powered stapler proves effective for performing gastrointestinal anastomosis procedures. [ABSTRACT FROM AUTHOR]

Magnetic resonance (MR) imaging is an important tool for prostate cancer diagnosis, and accurate segmentation of MR prostate regions by computer-aided diagnostic techniques is important for the diagnosis of prostate cancer. In this paper, we propose an improved end-to-end three-dimensional image segmentation network using a deep learning approach to the traditional V-Net network (V-Net) network in order to provide more accurate image segmentation results. Firstly, we fused the soft attention mechanism into the traditional V-Net's jump connection, and combined short jump connection and small convolutional kernel to further improve the network segmentation accuracy. Then the prostate region was segmented using the Prostate MR Image Segmentation 2012 (PROMISE 12) challenge dataset, and the model was evaluated using the dice similarity coefficient (DSC) and Hausdorff distance (HD). The DSC and HD values of the segmented model could reach 0.903 and 3.912 mm, respectively. The experimental results show that the algorithm in this paper can provide more accurate three-dimensional segmentation results, which can accurately and efficiently segment prostate MR images and provide a reliable basis for clinical diagnosis and treatment.