3D-IDS: Doubly Disentangled Dynamic Intrusion Detection

Network-based intrusion detection system (NIDS) monitors network traffic for malicious activities, forming the frontline defense against increasing attacks over information infrastructures. Although promising, our quantitative analysis shows that existing methods perform inconsistently in declaring various unknown attacks (e.g., 9% and 35% F1 respectively for two distinct unknown threats for an SVM-based method) or detecting diverse known attacks (e.g., 31% F1 for the Backdoor and 93% F1 for DDoS by a GCN-based state-of-the-art method), and reveals that the underlying cause is entangled distributions of flow features. This motivates us to propose 3D-IDS, a novel method that aims to tackle the above issues through two-step feature disentanglements and a dynamic graph diffusion scheme. Specifically, we first disentangle traffic features by a non-parameterized optimization based on mutual information, automatically differentiating tens and hundreds of complex features of various attacks. Such differentiated features will be fed into a memory model to generate representations, which are further disentangled to highlight the attack-specific features. Finally, we use a novel graph diffusion method that dynamically fuses the network topology for spatial-temporal aggregation in evolving data streams. By doing so, we can effectively identify various attacks in encrypted traffics, including unknown threats and known ones that are not easily detected. Experiments show the superiority of our 3D-IDS. We also demonstrate that our two-step feature disentanglements benefit the explainability of NIDS.Comment: Accepted and appeared in the proceedings of the KDD 2023 Research Trac

Composition and diversity of gut microbiota across developmental stages of Spodoptera frugiperda and its effect on the reproduction

IntroductionSpodoptera frugiperda is a serious world-wide agricultural pest. Gut microorganisms play crucial roles in growth, development, immunity and behavior of host insects.MethodsHere, we reported the composition of gut microbiota in a laboratory-reared strain of S. frugiperda using 16S rDNA sequencing and the effects of gut microbiota on the reproduction.ResultsProteobacteria and Firmicutes were the predominant bacteria and the taxonomic composition varied during the life cycle. Alpha diversity indices indicated that the eggs had higher bacterial diversity than larvae, pupae and adults. Furthermore, eggs harbored a higher abundance of Ralstonia, Sediminibacterium and microbes of unclassified taxonomy. The dynamics changes in bacterial communities resulted in differences in the metabolic functions of the gut microbiota during development. Interestingly, the laid eggs in antibiotic treatment groups did not hatch much due to the gut dysbacteriosis, the results showed gut microbiota had a significant impact on the male reproduction.DiscussionOur findings provide new perspectives to understand the intricate associations between microbiota and host, and have value for the development of S. frugiperda management strategies focusing on the pest gut microbiota

Resonant Frequency Tracking Scheme for <italic>LLC</italic> Converter Based on Large and Small Signal Combined Model

To achieve optimal system performance, it&#x2019;s recommended to operate an LLC resonant converter at its resonant frequency. However, in mass production, the resonant parameters of different products can deviate significantly. This means that we need to actively track the resonant frequency during practical usage. To address this issue, this paper presents a novel automatic control scheme for LLC converter that tracks the resonant frequency. The proposed control scheme is based on an accurate small-signal model, and an extended state observer which provides small-signal characteristics at the operating frequency. The controller checks the voltage gain of the converter and combines large-signal with small-signal models to control the LLC converter effectively. Compared to conventional automatic resonant frequency tracking (ARFT) control schemes, the proposed control scheme is easier to implement and requires fewer sensors. Experimental results demonstrate its effectiveness in tracking the resonant frequency. In summary, this manuscript proposes an effective ARFT control scheme for LLC converter that can track the resonant frequency with reduced sensors and is easier to implement

Gut dysbacteriosis induces expression differences in the adult head transcriptome of Spodoptera frugiperda in a sex-specific manner

Abstract Mounting evidence indicates that the gut microbiota influences the neurodevelopment and behavior of insects through the gut-brain axis. However, it is currently unclear whether the gut microbiota affect the head profiles and immune pathway in pests. Here, we find that gut bacteria is essential for the immune and neural development of adult Spodoptera frugiperda, which is an extremely destructive agricultural pest worldwide. 16 S rRNA sequencing analysis showed that antibiotics exposure significantly disturbed the composition and diversity of gut bacteria. Further transcriptomic analysis revealed that the adult head transcripts were greatly affected by gut dysbacteriosis, and differently expression genes critical for brain and neural development including A4galt, Tret1, nsun4, Galt, Mitofilin, SLC2A3, snk, GABRB3, Oamb and SLC6A1 were substantially repressed. Interestingly, the dysbacteriosis caused sex-specific differences in immune response. The mRNA levels of pll (serine/threonine protein kinase Pelle), PGRP (peptidoglycan-sensing receptor), CECA (cecropin A) and CECB (cecropin B) involved in Toll and Imd signaling pathway were drastically decreased in treated male adults’ heads but not in female adults; however, genes of HIVEP2, ZNF131, inducible zinc finger protein 1-like and zinc finger protein 99-like encoding zinc-finger antiviral protein (ZAP) involved in the interferon (IFNα/β) pathway were significantly inhibited in treated female adults’ heads. Collectively, these results demonstrate that gut microbiota may regulate head transcription and impact the S. frugiperda adults’ heads through the immune pathway in a sex-specific manner. Our finding highlights the relationship between the gut microbiota and head immune systems of S. frugiperda adults, which is an astonishing similarity with the discoveries of other animals. Therefore, this is the basis for further research to understand the interactions between hosts and microorganisms via the gut-brain axis in S. frugiperda and other insects

Laboratory investigation for the bridge deck pavement performance of conventional asphalt mixtures based on fuzzy comprehensive evaluation method

The performance of asphalt mixtures greatly influences the long-term performance of bridge deck pavements. It is essential to optimise the asphalt mixtures with the best overall performance according to different regional conditions for use in engineering practice. This study proposes a comprehensive assessment method based on the Analytical Hierarchy Process (AHP) and Fuzzy Comprehensive Evaluation (FCE) to evaluate the serviceability of asphalt mixtures from different perspectives. It is used to optimise the best asphalt mixtures. The results show that the skeleton-dense structure asphalt mixture has better engineering applicability than the suspension-dense structure asphalt mixture, and the comprehensive performance of the asphalt mixture decreases with the increase of the nominal maximum particle size. The FCE determines that the total performance of the seven types of asphalt mixtures in the order of their superiority and inferiority are SMA-13 >asphalt mastic sand (AMS)>SMA-10 >AC-25 >AC-13 >AC-16 >AC-20. The study combines qualitative and quantitative factors, which makes the selection of engineering materials more scientific and rigorous and improves the rationality of material suitability evaluation

Application of tone repair skincare product in the improvement of sensitive skin: Based on a cohort study of 60 cases

Objective To explore the role of functional skincare products in improving sensitive skin. Methods A total of 60 subjects with sensitive skin were selected by lactic acid sting test and randomly divided into the treated and control groups, 30 subjects per group. The treated group used tone repair skincare product and the untreated group served as the controls. The improvements in skin hydration, transepidermal water loss, a* value, redness area, and investigators' and subjects' self-evaluation scores were compared between the two groups 2 hours and 28 days after the applications. Results Compared to the control group, 28-day applications of tone repair skincare product significantly improved lactic acid sting scores (Z=-2.83, P<0.05). The stratum corneum hydration levels were increased both 2 hours and 28 days after topical applications of the products. In contrast, transepidermal water loss rates were dramatically decreased after 28-day applications (P<0.05, vs. controls). Both a* value and proportion of redness area were markedly decreased 2 hours after application of the product (P<0.05 for both). However, no significant differences in a* value and proportion of redness area were observed between the treated and control groups after 28-day applications. The investigators' assessment showed significant improvements in sensitive skin symptoms and sign, such as dryness, scales, telangiectasia and skin tightness in the treatment group compared to the control group (P<0.05). Conclusions Functional skincare products can improve the skin barrier function, playing an important role in improving the physiological state of sensitive skin

Detecting Recent Positive Selection with a Single Locus Test Bipartitioning the Coalescent Tree

Many population genomic studies have been conducted in the past to search for traces of recent events of positive selection. These traces, however, can be obscured by temporal variation of population size or other demographic factors. To reduce the confounding impact of demography, the coalescent tree topology has been used as an additional source of information for detecting recent positive selection in a population or a species. Based on the branching pattern at the root, we partition the hypothetical coalescent tree, inferred from a sequence sample, into two subtrees. The reasoning is that positive selection could impose a strong impact on branch length in one of the two subtrees while demography has the same effect on average on both subtrees. Thus, positive selection should be detectable by comparing statistics calculated for the two subtrees. Simulations demonstrate that the proposed test based on these principles has high power to detect recent positive selection even when DNA polymorphism data from only one locus is available, and that it is robust to the confounding effect of demography. One feature is that all components in the summary statistics (Du) can be computed analytically. Moreover, misinference of derived and ancestral alleles is seen to have only a limited effect on the test, and it therefore avoids a notorious problem when searching for traces of recent positive selection