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The Darknet is an anonymous, encrypted collection of websites, with a passive listening nature - accepting incoming packets, while not supporting outgoing packets. Thus, it can potentially host criminal or malicious activity and software, becoming a cyber security threat. Network Detection Systems are effective in identifying dark net traffic and mitigating its ill effects. However, capturing and extracting data from raw network traffic for training these systems can be time-intensive and costly. Using the CIC-Darknet 2020 dataset, this paper proposes using a Novel Generative Adversarial Networks (GAN) Architecture generating the required training and testing data for these systems. This uses a combination of Growing Cosine Unit (GCU) activated convolution layers and Dense layers for the Generator. Feature selection with statistical correlation methods is used to select the most relevant features. An independently trained Evaluator network is used to evaluate the generated data. The proposed system is compared to other established Tabular data GANs like Conditional Tabular GAN (CTGAN) and Copula GAN with similar parameters and on the same data. The Proposed GAN architecture outperforms CTGAN and CopulaGAN by 20 % and 10 % in ters of accuracy while also taking 90 % and 30 % less time to train respectively. Results from measuring similarity of data using the Inverted Kolmogorov - Smirnov D statistic also show significantly better results for the Proposed GAN Architecture. This shows significant promise in using Generative models to reduce the time and effort costs associated with collecting and formatting data to use in research and for training detection systems.

Vibrio parahaemolyticus is a leading cause of human gastroenteritis associated with seafood consumption. The present study aimed to investigate the occurrence and risk assessment of V. parahaemolyticus isolated from live Indian black clams, sediment, and water samples collected from shellfish harvesting areas located along the south-west coast of India. Out of the total 72 samples collected, 55.6% revealed the presence of V. parahaemolyticus; the highest occurrence was observed in shellfish samples. The presence of tdh and trh virulence genes was screened by multiplex PCR. Virulence genes could be detected in 25.8% of the strains; 19.35% of them were trh positive and 3.2% were tdh positive, while 3.2% of strains exhibited the coexistence of both virulence genes. Antimicrobial resistance (AMR) determined by the disk diffusion method revealed that 87% of the strains were multiple drug resistant and exhibited 21 diverse resistance patterns. The overall multiple antibiotic resistance (MAR) index values ranged from 0 to 0.8. To the best of our knowledge, this is the first report to document the presence of pathogenic and multidrug-resistant V. parahaemolyticus in shellfish harvesting areas of the Indian sub-continent. The study reveals possible health hazards associated with consuming shellfish harvested from the study area. [ABSTRACT FROM AUTHOR]

Understanding the surface properties of glass during the hydrogen fluoride (HF)-based vapor etching process is essential to optimize treatment processes in semiconductor and glass industries. In this work, we investigate an etching process of fused glassy silica by HF gas with kinetic Monte Carlo (KMC) simulations. Detailed pathways of surface reactions between gas molecules and the silica surface with activation energy sets are explicitly implemented in the KMC algorithm for both dry and humid conditions. The KMC model successfully describes the etching of the silica surface with the evolution of surface morphology up to the micron regime. The simulation results show that the calculated etch rate and surface roughness are in good agreement with the experimental results, and the effect of humidity on the etch rate is also confirmed. Development of roughness is theoretically analyzed in terms of surface roughening phenomena, and it is predicted that the values of growth and roughening exponents are 0.19 and 0.33, respectively, suggesting that our model belongs to the Kardar–Parisi–Zhang universality class. Furthermore, the temporal evolution of surface chemistry, specifically surface hydroxyls and fluorine groups, is monitored. The surface density of fluorine moieties is 2.5 times higher than that of the hydroxyl groups, implying that the surface is well fluorinated during vapor etching. [ABSTRACT FROM AUTHOR]

Contact charging of hydroxylated SiO2/metal interfaces is studied using density functional theory calculations. Atomic scale models are generated for hydroxylated α-cristobalite interfaced with three different fcc metals: Al, Pt, and Au. Regions of electron accumulation and depletion are highest in magnitude near the SiO2/Pt and SiO2/Au interfaces and lower at the SiO2/Al interface. One key finding of this work is that the presence of a metal surface near the hydroxylated SiO2 induces electronic states at the SiO2 surface within the apparent insulating bandgap. The magnitude of these states is highest for Pt and Au contacts and lowest for Al, indicating that the amount of charge transfer at the interface trends with the density of electronic defect states. Such electronic defect states reside near the fermi level of the system and it is proposed that these states from surface oxygen atoms are at least partly responsible for the electronic charge transfer mechanism between a metal and an insulator. [ABSTRACT FROM AUTHOR]

This work was aimed at immobilization, characterization, and utilization of chitinase from Kurthia gibsonii Mb126. Immobilization of Kurthia gibsonii Mb126 chitinase on glutaraldehyde treated chitosan was carried out with immobilization yield of 106%. The optimal factors of the immobilization technique such as concentration of glutaraldehyde, chitinase concentration, and immobilization time were evaluated. After optimizing process parameters of immobilization (Glutaraldehyde concentration 4%, chitinase conc. 60mg, immobilization time 30min.), the specific activity of immobilized chitinase improved to 4.3-fold compared to the free form of chitinase. Temperature and pH optima of the immobilized chitinase and free enzyme were same i.e., 7.5 and 40°C respectively. The relative activity of immobilized chitinase remained 90% at 40°C, at 50°C, and at 60°C for 120 min. In the pH range from 5.5 to 8, the immobilized chitinase retained 100% activity. The results confirmed that the pH stability and thermal stability of chitinase increased by immobilizing chitinase on chitosan. The immobilized enzyme system maintained 90% of its efficiency even after 16 successive reaction cycles. The immobilized chitinase maintained 78% of its activity even after 20 months. Fermentation of prawn shell waste with immobilized chitinase indicated a high level of deproteinization. Deproteinization experiments were carried out with 5mL (0.4 mg/mL) of immobilized and free chitinase on 300 mg/mL of prawn shell waste for 20 days without any additional supplements at 40°C and 6.5 pH. Protein content was reduced from 38.4 to 0.8% with immobilized chitinase. Results suggests the possibility of using immobilized enzymes to remove the prawn shell waste from the environment. To the best of our knowledge there was no such study about the deproteinization of prawn shell waste using immobilized chitinase till the date. [ABSTRACT FROM AUTHOR]

Background: The survival of pathogens in biofilms poses a threat to food safety. The aim of this study was to determine prevalence, antimicrobial resistance, and molecular characterization of Escherichia coli strains. Methods: Swab samples (n=144) were collected from biofilm formed on food contact surfaces in seafood pre-processing plant in India. E. coli was isolated and identified using uid A gene by Polymerase Chain Reaction (PCR). The risk assessment of the isolates was carried out in terms of their drug resistance and the presence of virulence genes. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method. Phylogenetic grouping was done by quadruplex PCR. Molecular typing of the strains was performed by Enterobacterial Repetitive Intergenic Consensus-PCR (ERICPCR). Data were statistically analyzed using SPSS version 22. Results: Enteropathogenic E. coli (EPEC) strains were the most prevalent serotype. Multiplex PCR analysis revealed the presence of shiga toxin genes (stx1, stx2), intimin (eae), and enterohemolysin genes (hlyA). Shiga toxin gene stx2 showed the highest prevalence (83.33%). Among various phylogroups, B1 (45.56%) and B2 (30%) were the most prevalent phylogroups. Resistance to ampicillin (85.56%), piperacillin (84.44%), and cefpodoxime (85.56%) was widespread among the E. coli strains. Conclusion: The presence of genetically heterogeneous multi drug resistant E. coli strains with virulence potential showed a high risk in the seafood industry. [ABSTRACT FROM AUTHOR]