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Quasi-strongly regular graphs form a significant generalization of strongly regular graphs. We study the eigenvalues of a family of such graphs, Γ_H(G), constructed from a finite group G and a subgroup H. Our main results include a sufficient condition for Γ_H(G) to be integral and an explicit computation of its entire spectrum when H is normal, revealing that the spectrum in this case depends only on |G| and the index [G:H].
Microplastics are a rising global contaminant of concern that impacts aquatic ecosystems and their food chains. This study examined the occurrence, distribution, and characteristics of microplastics in the gut of three important commercial fish species (N = 120) collected from Pulicat Lake. The samples were collected across the lake, digested, and analyzed using FTIR. Microplastics were identified in almost all samples, with fibres being the most abundant type. Black particles (100–200 μm) were also observed. The most dominant polymer types were polyethylene (PE), phenol-formaldehyde (PF), and epoxy resin (ER). The highest microplastic abundance was recorded in A. mate (3.6 ± 0.74 particles/individual), followed by L. splendens (2.4 ± 0.2 particles/individual) and T. ilisha (2.2 ± 0.60 particles/individual). Phenol-formaldehyde (PF) showed the highest hazard, with a PHI of 15,000, classifying it as Hazard Category V (Very High Hazard). Similarly, TPV exhibited a very high hazard potential, with a PHI of 7293.33, also falling within Category V. These findings highlight the prevalence of microplastic pollution in Pulicat Lake and its potential risks to the marine environment and human health.
Ransomware has become the quintessential malware weapon of the digital crime era. In this chapter, we explore the world of ransomwares through the lens of organised crime studies to examine the networks, markets and digital power of ransomware groups like Conti, LockBit, REvil and ALPHV/BlackCat. The chapter outlines the structure, market mechanisms and power dynamics that characterize modern day ransomware operations. Utilizing in-depth case studies of large ransomware businesses and law enforcement disruption efforts, the chapter argues that ransomware groups are not simply a category of cybercrime but are a maturing of organized criminal enterprise that is uniquely suited for the networked digital environment. The analysis offers ideas regarding theoretical development concepts and the practical implications for intelligence-led policing, cross-border collaboration and criminal disruption in an increasingly contested cyber security environment, as well as criminal network resilience and governance of the illicit markets.
The ever-evolving field of organised cybercrime now faces significant threats from synthetic media, deepfakes, and AI-enabled identity manipulation. Business email compromise, social manipulation, financial deceit, cyber extortion, political misinformation, and reputational assaults are some of the more common uses of these technologies. The use of synthetic media allows coordinated cybercriminal organisations to evade traditional authentication systems, enable deceit, and carry out complex schemes all over the globe. Now that generative AI tools are readily available, criminal groups may easily and cheaply produce realistic counterfeit stuff. Deepfakes and synthetic media are discussed in this chapter along with their technical foundations, new attack methodologies, integration into organised cybercriminal enterprises, ethical and legal concerns, methods of identity manipulation, detection strategies, and potential approaches to combating digital fraud enabled by artificial intelligence.
Polyaniline (PANI 1,3 and 5wt %) /cerium modified magnesium oxide (Ce-MgO) nanocomposites were synthesized using a chemical precipitation technique. XRD, FTIR, SEM-EDX, TEM, UV-DRS, PL, and BET investigations were used to examine structural and physicochemical character of synthesized catalysts. XRD verified the crystalline structure of Ce-MgO and the nanocomposites, while PANI showed an amorphous structure. UV-DRS revealed a reduction in band gap with increasing PANI content, enhancing visible-light absorption. The photocatalytic activity was evaluated by means of Rhodamine B degradation under visible-light irradiation, considering key reaction parameters. The 3PCM nanocomposite exhibited the highest efficiency, achieving 92.76% degradation within 210min. Additionally, the nanocomposites demonstrated effective electrochemical sensing of dopamine. These results highlight the multifunctional potential of PANI/Ce-MgO nanocomposites for visible-light-driven photocatalytic and electrochemical applications.
