The authors introduce basic concepts in SNA, along with methods for data collection, data processing, data analysis, and conduct analyses of a study relationship network. Also covered are generative processes that create observed study networks and practical issues, such as the unique aspects of human subjects review for network studies.

Increased size of eukaryotic genomes necessitated the use of multiple origins of DNA replication, and presumably selected for their efficient spacing to ensure rapid DNA replication. The sequence of these origins remains undetermined in metazoan genomes, leaving important questions about the selective constraints acting on replication origins unanswered. We have chosen to study the evolution of proteins that recognize and define these origins every cell cycle, as a surrogate to the direct analysis of replication origins.

Macrophages have diverse functions in immunity as well as development and homeostasis. Here we identify a function for these cells in long distance communication during postembryonic tissue remodeling. Ablation of macrophages in zebrafish prevented melanophores from coalescing into adult pigment stripes. Melanophore organization depends on signals provided by cells of the yellow xanthophore lineage via airinemes, long filamentous projections with vesicles at their tips.

For many years, a main focus of plant evolutionary developmental biology was studying the expression and phylogenetic history of genes implicated in developmental pathways. This approach has been enormously successful in identifying potentially conserved gene regulatory circuits that underlie major pattern formation processes in plants. Importantly, hypotheses were often generated on how changes in these gene regulatory-circuits led to the evolution of different plant forms.

Impairment of immune defenses can contribute to severe influenza infections. Rapamycin is an immunosuppressive drug often used to prevent transplant rejection and is currently undergoing clinical trials for treating cancers and autoimmune diseases. We investigated whether rapamycin has deleterious effects during lethal influenza viral infections. We treated mice with two concentrations of rapamycin and infected them with A/Puerto Rico/8/1934 (A/PR8), followed by a heterosubtypic A/Hong Kong/1/68 (A/HK68) challenge.