Network Intrusion Detection Based on Directed Acyclic Graph and Belief Rule Base

Bang-Cheng Zhang,Guan-Yu Hu,Zhi-Jie Zhou,You-Min Zhang,Pei-Li Qiao,Lei-Lei Chang 한국전자통신연구원 2017 ETRI Journal Vol.39 No.4

Intrusion detection is very important for network situation awareness. While a few methods have been proposed to detect network intrusion, they cannot directly and effectively utilize semi-quantitative information consisting of expert knowledge and quantitative data. Hence, this paper proposes a new detection model based on a directed acyclic graph (DAG) and a belief rule base (BRB). In the proposed model, called DAG-BRB, the DAG is employed to construct a multi-layered BRB model that can avoid explosion of combinations of rule number because of a large number of types of intrusion. To obtain the optimal parameters of the DAG-BRB model, an improved constraint covariance matrix adaption evolution strategy (CMA-ES) is developed that can effectively solve the constraint problem in the BRB. A case study was used to test the efficiency of the proposed DAG-BRB. The results showed that compared with other detection models, the DAG-BRB model has a higher detection rate and can be used in real networks.

Biotransformation of natural polyacetylene in red ginseng by Chaetomium globosum

Wang, Bang-Yan,Yang, Xue-Qiong,Hu, Ming,Shi, Li-Jiao,Yin, Hai-Yue,Wu, Ya-Mei,Yang, Ya-Bin,Zhou, Hao,Ding, Zhong-Tao The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.6

Background: Fermentation has been shown to improve the biological properties of plants and herbs. Specifically, fermentation causes decomposition and/or biotransformation of active metabolites into high-value products. Polyacetylenes are a class of polyketides with a pleiotropic profile of bioactivity. Methods: Column chromatography was used to isolate compounds, and extensive NMR experiments were used to determine their structures. The transformation of polyacetylene in red ginseng (RG) and the production of cazaldehyde B induced by the extract of RG were identified by TLC and HPLC analyses. Results: A new metabolite was isolated from RG fermented by Chaetomium globosum, and this new metabolite can be obtained by the biotransformation of polyacetylene in RG. Panaxytriol was found to exhibit the highest antifungal activity against C. globosum compared with other major ingredients in RG. The fungus C. globosum cultured in RG extract can metabolize panaxytriol to Metabolite A to survive, with no antifungal activity against itself. Metabolites A and B showed obvious inhibition against NO production, with ratios of 42.75 ± 1.60 and 63.95 ± 1.45% at 50 µM, respectively. A higher inhibitory rate on NO production was observed for Metabolite B than for a positive drug. Conclusion: Metabolite A is a rare example of natural polyacetylene biotransformation by microbial fermentation. This biotransformation only occurred in fermented RG. The extract of RG also stimulated the production of a new natural product, cazaldehyde B, from C. globosum. The lactone in Metabolite A can decrease the cytotoxicity, which was deemed to be the intrinsic activity of polyacetylene in ginseng.

Knockdown of the olfactory co-receptor Orco impairsmate recognition in Tenebrio molitor (Coleoptera: Tenebrionidae)

Xiao-Ming Liu,Bang-Xian Zhang,Shi-Guang Li,Xiang-Jun Rao,Dong-MingWang,Xiao-Xuan Hu,Su Liu 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.2

The yellow mealworm beetle, Tenebrio molitor (Coleoptera: Tenebrionidae), is a common insect pest that damages stored grain. The insect olfactory co-receptor (Orco) is a transmembrane protein localized on the surface of the dendrites of olfactory sensory neurons and plays an essential role in the olfactory perception. In this study, an Orco ortholog (named as Tmol\Orco) inT.molitorwas characterized. The deduced amino acid sequence of Tmol\Orco shared significant high identities with Orcos in other insect species from distinct Orders. Reverse transcription quantitative PCR (RT-qPCR) analysis showed that Tmol\Orco was predominantly expressed in the antennae of both male and female adults, and the difference between male antennae and female antennae was not significant. Double-stranded RNA (dsRNA) directly against the Tmol\Orco mRNA was synthesized and injected into the T. molitor male adults, RT-qPCR results demonstrated that the transcription level of Tmol\Orco was significantly reduced at 6 d after the injection. The mate-seeking behavior of Tmol\Orco-silenced beetles was significantly inhibited. Compare to the control individuals, the percentage of Tmol\Orco-silenced beetles successfully find mateswas significantly decreased and the average time they spent for searching were significantly increased. These results provided first direct evidence that suppression of Tmol\Orco transcription contributes to the decline in mate recognition of T. molitor

Privet golden leaves adapt unexpectedly well to light changes

Ming Yuan,Bo Huang,Li-Hua Dong,Qiao-Hong Han,Yong Yang,Chun-Bang Ding,Chao Hu,Yang-Er Chen,Zhong-Wei Zhang,Shu Yuan 한국원예학회 2020 Horticulture, Environment, and Biotechnology Vol.61 No.4

Golden-leaf privet ( Ligustrum × vicaryi ) is widely used as a horticultural shrub because of its upper golden leaves, butits lower leaves are green. However, the putative mechanisms of its upper golden leaves and the leaf color changes inresponse to light shifts have not been well studied so far. Here, chlorophylls (Chl), carotenoids, and Chl precursors from bothgolden and green leaves grown in full sunlight (approximately 1200 μmol photons m −2 s −1 at noon) or low-light conditions(180 μmol m −2 s −1 ) were determined spectrophotometrically. In addition, their gas exchange parameters and Chl fl uorescencewere measured in situ. Metabolic fl ux analysis of chlorophyll intermediates indicated that the conversion of prochlorophyllideto chlorophyllide was signifi cantly blocked in golden leaves when compared with green leaves. Green leaves showed higherphotosynthetic capacity in low light than golden leaves, but golden leaves presented unexpectedly stronger photosyntheticcapacity and lower reactive oxygen species accumulation under the high-light condition. Furthermore, golden leaves showeda higher level of nonphotochemical quenching (NPQ) after the light-to-dark shift and presented a stronger adaptive abilityto a broad range of light environments. Higher NPQ values and less oxidative damage in golden leaves may be correlatedwith their higher carotenoid levels. The results imply that lower chlorophyll levels and higher carotenoid levels in canopyleaves may help privet plants acclimate better to illumination changes. This study demonstrates the key role of irradiance ingenerating the two types of Ligustrum × vicaryi leaves and sheds a light on cultivation of other ornamental foliage plants.

Association of Helicobacter pylori with Elevated Blood Ammonia Levels in Cirrhotic Patients: A Meta-Analysis

Hai-Xing Jiang,Shan-Yu Qin,Zhi-gang Min,Ming-Zhi Xie,Tao Lin,Bang-Li Hu,Xiao-Yun Guo 연세대학교의과대학 2013 Yonsei medical journal Vol.54 No.4

Purpose: The association between Helicobacter pylori (H. pylori) and blood ammonia levels in cirrhotic patients is controversial. We aimed to clarify this controvercy by performing a meta-analysis of published studies. Materials and Methods:We searched PubMed, EMBASE and Cochrane library for studies which explored the association between H. pylori and blood ammonia levels in cirrhotic patients before May 2012. Six cohort studies involved in 632 H. pylori positive and 396 H. pylori negative cirrhotic patients were eligible for our analysis. The summary estimates were presented as standard means differences (SMD) and 95% confidence intervals (CI) from individual studies. Results: Overall, there was significant association between H. pylori infection and the elevated blood ammonia levels in cirrhotic patients (SMD=0.34, 95% CI=0.21-0.47, I2=42.1%). Sensitivity analysis further confirmed this association. Subgroup analysis showed that the association was found only in Asian ethnicity, but not in Caucasian ethnicity. Conclusion:H. pylori infection is associated with elevated blood ammonia levels in cirrhotic patients, and more large scale studies and stratify analysis are warranted in order to further evaluate this association.