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The massive trend toward embedded systems introduces new security threats to prevent. Malicious firmware makes it easier to launch cyberattacks against embedded systems. Systems infected with malicious firmware maintain the appearance of normal firmware operations but execute undesirable activities, which is usually a security risk. Traditionally, cybercriminals use malicious firmware to develop possible back-doors for future attacks. Due to the restricted resources of embedded systems, it is difficult to thwart these attacks using the majority of contemporary standard security protocols. In addition, monitoring the firmware operations using existing side channels from outside the processing unit, such as electromagnetic radiation, necessitates a complicated hardware configuration and in-depth technical understanding. In this paper, we propose a physical side channel that is formed by detecting the overall impedance changes induced by the firmware actions of a central processing unit. To demonstrate how this side channel can be exploited for detecting firmware activities, we experimentally validate it using impedance measurements to distinguish between distinct firmware operations with an accuracy of greater than 90%. These findings are the product of classifiers that are trained via machine learning. The implementation of our proposed methodology also leaves room for the use of hardware authentication. 

Genetic variants in SCN2A, encoding the NaV1.2 voltage-gated sodium channel, are associated with a range of neurodevelopmental disorders with overlapping phenotypes. Some variants fit into a framework wherein gain-of-function missense variants that increase neuronal excitability lead to developmental and epileptic encephalopathy, while loss-of-function variants that reduce neuronal excitability lead to intellectual disability and/or autism spectrum disorder (ASD) with or without co-morbid seizures. One unique case less easily classified using this framework is the de novo missense variant SCN2A-p.K1422E, associated with infant-onset developmental delay, infantile spasms and features of ASD. Prior structure–function studies demonstrated that K1422E substitution alters ion selectivity of NaV1.2, conferring Ca2+ permeability, lowering overall conductance and conferring resistance to tetrodotoxin (TTX). Based on heterologous expression of K1422E, we developed a compartmental neuron model incorporating variant channels that predicted reductions in peak action potential (AP) speed. We generated Scn2aK1422E mice and characterized effects on neurons and neurological/neurobehavioral phenotypes. Cultured cortical neurons from heterozygous Scn2aK1422E/+ mice exhibited lower current density with a TTX-resistant component and reversal potential consistent with mixed ion permeation. Recordings from Scn2aK1442E/+ cortical slices demonstrated impaired AP initiation and larger Ca2+ transients at the axon initial segment during the rising phase of the AP, suggesting complex effects on channel function. Scn2aK1422E/+ mice exhibited rare spontaneous seizures, interictal electroencephalogram abnormalities, altered induced seizure thresholds, reduced anxiety-like behavior and alterations in olfactory-guided social behavior. Overall, Scn2aK1422E/+ mice present with phenotypes similar yet distinct from other Scn2a models, consistent with complex effects of K1422E on NaV1.2 channel function.

 

As the world becomes more interconnected and our lives increasingly depend on the cyber world, the increasing threat of cyberattacks and cybercrimes make it critical for us to provide better and practical training of the cybersecurity workforce. In recent years, cybersecurity competition has become one of the most effective and attractive way for educating and training college students or professionals. In this paper, we first systematically introduce in details the step-by-step procedure and technical knowledge on how we take use of the ongoing DoD cyber-range environment called Persistent Cyber Training Environment (PCTE) to set up cyber competition virtualization environment, configure and install operating systems and popular services with various well-representative vulnerabilities, and set up the participant’s access and scoring system. Then we introduce the cybersecurity competition successfully organized by us in I/ITSEC 2019 conference, and the experience and lessons learned from this real-world competition event. The technical details and knowledge presented in this paper could help other researchers and educators to set up their own cyber competition environment or event to better train the future cybersecurity workforce. 

Interaction conditions can change the balance of cooperation and conflict in multicellular groups. After aggregating together, cells of the social amoebaDictyostelium discoideummay migrate as a group (known as a slug) to a new location. We consider this migration stage as an arena for social competition and conflict because the cells in the slug may not be from a genetically homogeneous population. In this study, we examined the interplay of two seemingly diametric actions, the solitary action of kin recognition and the collective action of slug migration inD. discoideum, to more fully understand the effects of social competition on fitness over the entire lifecycle. We compare slugs composed of either genetically homogenous or heterogeneous cells that have migrated or remained stationary in the social stage of the social amoebaDictyostelium discoideum. After migration of chimeric slugs, we found that facultative cheating is reduced, where facultative cheating is defined as greater contribution to spore relative to stalk than found for that clone in the clonal state. In addition our results support previous findings that competitive interactions in chimeras diminish slug migration distance. Furthermore, fruiting bodies have shorter stalks after migration, even accounting for cell numbers at that time. Taken together, these results show that migration can alleviate the conflict of interests in heterogeneous slugs. It aligns their interest in finding a more advantageous place for dispersal, where shorter stalks suffice, which leads to a decrease in cheating behavior.