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Hardware joined the battle against malware by introducing secure boot architectures, malware-aware processors, and trusted platform modules. Hardware performance indicators, power profiles, and side channel information can be leveraged at run-time via machine learning for continuous monitoring and protection. The explainability of these machine learning algorithms may play a crucial role in interpreting their results and avoiding false positives. In this paper, we present an eagle eye on the state of the art of these components: we examine secure architectures and malware-aware processors, such as those implemented in the RISC-V Instruction Set Architecture and Reduced Instruction Set Computer (RISC). We categorize hardware-assisted solutions increased by machine learning for classification. We survey recently proposed software-assisted and hardware-assisted explainability algorithms in our context. In the discussion, we suggest that (1) safe architectures that guarantee secure device boot are a must, (2) Side-channel approaches are challenging to integrate into embedded systems, yet they show promise in terms of efficiency, (3) malware-aware processors provide valuable features for malware detection software, and (4) Without explainability, malware detection software is error-prone and can be easily bypassed.

Corticosterone (CORT) inhibits development during early larval stages, but accelerates development in later stages in Bufo boreas. In contrast, studies from the literature suggest that COPT inhibits development in XENOPUS LAEVIS. We proposed that there is not a species difference in response to CORT, but rather differences in experimental design and the timing of hormone treatments. The current study tested the hypothesis that X. laevis would show similar dual responses to CORT depending on the stages during which they were treated. We initiated COPT treatments in X. laevis larvae at five stages (Nieuwkoop-Faber: 48, 52, 54, 56, and 58) with continued treatment throughout larval development. The higher dose (200 ng/mL) inhibited development when initiated at stages 48-56, but resulted in high mortality. CORT did not affect developmental rates when treatments began at stage 58, but there was an increase in mortality. The lower dose inhibited development when treatments began at stage 48, but had no effect at later stages. We conclude that CORT may be inhibitory throughout development. Ongoing studies examine the effects of COPT on pre- and prometamorphic (near stage 58) X. laevis larvae and the in vitro effects on development. This study was supported by an HHMI undergraduate grant and NSF grants (IBN-9513362 and IBN-9508996).

Abstract Background MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression implicated in multiple cellular processes. Cyclic stretch of alveoli is characteristic of mechanical ventilation, and is postulated to be partly responsible for the lung injury and inflammation in ventilator-induced lung injury. We propose that miRNAs may regulate some of the stretch response, and therefore hypothesized that miRNAs would be differentially expressed between cyclically stretched and unstretched rat alveolar epithelial cells (RAECs). Results RAECs were isolated and cultured to express type I epithelial characteristics. They were then equibiaxially stretched to 25% change in surface area at 15 cycles/minute for 1 hour or 6 hours, or served as unstretched controls, and miRNAs were extracted. Expression profiling of the miRNAs with at least 1.5-fold change over controls revealed 42 miRNAs were regulated (34 up and 8 down) with stretch. We validated 6 of the miRNAs using real-time PCR. Using a parallel mRNA array under identical conditions and publicly available databases, target genes for these 42 differentially regulated miRNAs were identified. Many of these genes had significant up- or down-regulation under the same stretch conditions. There were 362 down-regulated genes associated with up-regulated miRNAs, and 101 up-regulated genes associated with down-regulated miRNAs. Specific inhibition of two selected miRNAs demonstrated a reduction of the increased epithelial permeability seen with cyclic stretch. Conclusions We conclude that miRNA expression is differentially expressed between cyclically stretched and unstretched alveolar epithelial cells, and may offer opportunities for therapeutic intervention to ameliorate stretch-associated alveolar epithelial cell dysfunction.

Abstract Background In animals with heteromorphic sex chromosomes, dosage compensation of sex-chromosome genes is thought to be critical for species survival. Diverse molecular mechanisms have evolved to effectively balance the expressed dose of X-linked genes between XX and XY animals, and to balance expression of X and autosomal genes. Dosage compensation is not understood in birds, in which females (ZW) and males (ZZ) differ in the number of Z chromosomes. Results Using microarray analysis, we compared the male:female ratio of expression of sets of Z-linked and autosomal genes in two bird species, zebra finch and chicken, and in two mammalian species, mouse and human. Male:female ratios of expression were significantly higher for Z genes than for autosomal genes in several finch and chicken tissues. In contrast, in mouse and human the male:female ratio of expression of X-linked genes is quite similar to that of autosomal genes, indicating effective dosage compensation even in humans, in which a significant percentage of genes escape X-inactivation. Conclusion Birds represent an unprecedented case in which genes on one sex chromosome are expressed on average at constitutively higher levels in one sex compared with the other. Sex-chromosome dosage compensation is surprisingly ineffective in birds, suggesting that some genomes can do without effective sex-specific sex-chromosome dosage compensation mechanisms.