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With the increasingly widespread use of the Internet, various network security problems are frequently exposed, while the “patching” style security enhancement mechanisms cannot effectively prevent the growing security risks.The researchers in the field of network security believe that the future Internet architecture should take security as a basic attribute to provide the native security support which is also called as endogenous safety and security.In order to support the data trustworthiness of endogenous security, a time-slot based multiple redundant flow fingerprint model was designed and implemented based on the research of the watermark (or fingerprint) mechanism.The proposed model used only three time slot intervals and operated the packets within the specified time slots, so that the fingerprint can be embedded without conflicting with the adjacent bit operations.Redundant coding was introduced to improve the fingerprint robustness, and the behaviors such as jitter or malicious disruptions by attackers in the network were considered.Furthermore, the impacts of delayed interference, spam packet interference and packet loss interference were analyzed.The analytical results show that the robustness of the fingerprint model improves with increasing redundant bits when the packet distribution in the network stream is given.Besides, in order to reduce the consumption of time and space and improve the efficiency and accuracy of packet operations, a flow fingerprinting prototype system was designed and implemented based on the kernel, and its efficiency and robustness were evaluated.The experimental result show that the model has high robustness.Additionally, the application scenario of the model was elaborated, which can effectively detect man-in-the-middle attacks and prevent network identity spoofing with the help of the flow fingerprinting model.

Objective To investigate the effect of upstream transcription factor 2 (USF2) on the proliferation and apoptosis of human gastric cancer BGC-823 cells. Methods Lipofectamine?3000 transfection reagent was used to transfect USF2 siRNA into BGC-823 cells (siRNA-USF2 group). Blank control and negative control (siRNA-NC) groups were also prepared. The mRNA and protein expression levels of USF2 in transfected BGC-823 cells were detected by real-time fluorescence quantitative PCR and Western blot, respectively. The proliferation and clone formation abilities of BGC-823 cells in each group were investigated by CCK-8 and plate cloning assay. The apoptosis of gastric cancer cells was examined by flow cytometry. The expression levels of PCNA and apoptosis-related proteins Bax and Bcl-2 in BGC-823 cells were measured by Western blot. Results Compared with those in the blank control and siRNA-NC groups, the mRNA and protein expression levels of USF2 significantly decreased in the siRNA-USF2 group (P < 0.05). At 72 h after transfection, the absorbance in the siRNA-USF2 group was lower than that in the blank control group (P < 0.05). Compared with that in the blank control and siRNA-NC groups, the number of BGC-823 cell clones significantly decreased in the siRNA-USF2 group (P < 0.05). The apoptosis rate of BGC-823 cells significantly differed among the blank control, siRNA-NC, and siRNA-USF2 groups (P < 0.05). Compared with those in the blank control and siRNA-NC groups, the expression of PCNA and Bcl-2 protein decreased and that of Bax protein increased in the siRNA-USF2 group (P < 0.05). Conclusion Inhibiting USF2 expression can suppress the proliferation of human gastric cancer cells and induce their apoptosis. USF2 inhibitors may have important value in the treatment of gastric cancer.

Due to the variable working environment of bearings, the collected data often follow different probability distributions. It is hard to directly use the trained models to identify the bearing fault with different operating conditions. In addition, it is a high cost to label the samples for every work condition. To solve these problems, a multi-scale adversarial subdomain adaptation bearing fault diagnosis method is proposed, which is based on Continuous Wavelet Transform (CWT) and our constructed Multi-scale Adversarial SubDomain Adaptation Network (MASDAN). Firstly, to extract the features of non-stationary signals with different frequency bands, CWT is used to convert continuous vibration signals into two-dimensional time-frequency images. Secondly, to enhance the correlation of the features across frequency bands, a multi-scale ConvNeXt is proposed, which adds a multi-scale module based on ConvNeXt to obtain features with different scales. Finally, to reduce the distribution discrepancy between the source domain and the target domain and to avoid feature confusion in different domains, a domain adaptive alignment network introducing domain information is constructed. Two modules are included: the Domain Alignment Classification Network Module (DACNM) based on Multi-kernel Local Maximum Mean Discrepancy (MK-LMMD) and the Domain Adversarial Network Module (DANM) based on domain discrimination. Thus, the MASDAN consists of the multi-scale ConvNeXt module, DACNM, and DANM, which can realize the multi-scale feature extraction and adaptively align the fault features at different domains. The experimental results on the Qingdao University of Technology (QUT) bearing dataset and the Case Western Reserve University (CWRU) bearing dataset demonstrate the proposed method can effectively diagnose bearing faults under different operating conditions. [ABSTRACT FROM AUTHOR]

In this paper, we show that industry volatility concentration is a strong predictor for aggregate stock market returns. Our monthly industry volatility concentration (IVC) index displays significant predictive ability, with in‐sample and out‐of‐sample R2 statistics of 0.686% and 0.712%, respectively, which outperforms a host of prevailing return predictors. Moreover, the IVC index can generate high utility gains of 143.8 basis points above the historical average benchmark for mean–variance investors. We find that the IVC index is countercyclical. Furthermore, the predictive source of the IVC index not only stems from the cash flow and discount rate channels but is also explained by the channels of investor attention and sentiment. The predictive ability of our IVC index also remains significant under a broad range of robustness tests. [ABSTRACT FROM AUTHOR]

The influence of adding surfactants on the performance of high-solid anaerobic digestion of horticultural waste was extensively investigated in batch systems. Adding Tween series and polyethylene glycol series non-ionic surfactants had positive effects on biogas production, resulting in 370.1 mL/g VS and 256.6 mL/g VS with Tween 60 and polyethylene glycol 300 at a surfactant-to-grass mass ratio of 0.20, while the biogas production of anaerobic digestion without surfactants was 107.54 mL/g VS. The optimal and economically feasible choice was adding Tween 20 at a ratio of 0.08 g/g grass in high-solid anaerobic digestion. A kinetics model reliably represented the relationship between surfactant concentration and biogas production. The mechanism of surfactants working on lignocellulose was investigated. The improvement in high-solid anaerobic digestion by adding surfactants was attributed to the interaction between lignocelluloses and surfactants and the extraction of biodegradable fractions from the porous structure. An economic analysis showed that adding Tween 20 was likely to make a profit and be more feasible than adding Tween 60 and polyethylene glycol 300. This study confirms the enhancement in biogas production from horticultural waste by adding non-ionic surfactants. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to assess whether sequential cochlear implantation (CI) with a prolonged interimplant interval (M = 15.2 years) between the first and second CIs benefited speech recognition and health-related quality of life. Method: This prospective study included 14 prelingually deafened participants who received their second CI after a prolonged interimplant interval (M = 15.2 years). Additionally, speech recognition ability over a 12-month period of bilateral implant use was investigated. The results of the speech recognition test in both quiet and noisy conditions were statistically analyzed for each CI alone and both CIs together. Nijmegen Cochlear Implant Questionnaire scores were also collected at activation and at 12 months after activation. Results: Improvements in speech recognition ability were observed following the use of the first implant alone and with the use of both implants together; however, progress was much slower with the use of the second implant alone, following its introduction. Furthermore, a significant difference in the trajectory of speech recognition ability was observed between the first and the second implanted ear. According to Nijmegen Cochlear Implant Questionnaire scores, all participants benefitted from bilateral CI after 12 months. Conclusions: Prolonged interimplant intervals resulted in asymmetrical speech recognition abilities. A significant improvement in the speech recognition scores was observed with the first implanted ear, and much slower progress was observed with the second implanted ear. However, the "poorer" second implanted ear could provide a considerable beneficial effect on the improved speech recognition and health-related quality of life with the bilateral CI.

This study investigates the global adaptive prescribed performance control (PPC) of a class of uncertain strict‐feedback nonlinear systems with sensor faults based on the switching periodic event‐triggering mechanism (SPETM). Due to the existence of sensor faults, the controlled system is first remodeled by utilizing the available variables. To reduce the communication frequency, a novel SPETM is proposed by combining the advantages of the static and the dynamic event‐triggering mechanisms. This mechanism can not only avoid continuously monitoring the event‐triggering condition and avoid the Zeno phenomenon in mechanism, but also reduce the trigger frequency while ensuring the system performance by adjusting the event‐triggering threshold dynamically. Meanwhile, a time‐varying scaling function, whose reciprocal is considered as a prescribed performance function, is designed to achieve the global PPC by combining the nonlinear transformation technique. The adaptive control algorithm design is completed by employing the backstepping methodology, which can guarantee that all closed‐loop signals are bounded and the actual system output signal evolves within the prescribed performance boundary for arbitrary initial values. The effectiveness and the advantages of the proposed control algorithm are illustrated through an application example of the network‐based robotic manipulator system. [ABSTRACT FROM AUTHOR]