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Extensive portions of the human genome have unknown function, including those derived from transposable elements. One such element, the DNA transposon Hsmar1, entered the primate lineage approximately 50 million years ago leaving behind terminal inverted repeat (TIR) sequences and a single intact copy of the Hsmar1 transposase, which retains its ancestral TIR-DNA-binding activity, and is fused with a lysine methyltransferase SET domain to constitute the chimeric SETMAR gene. Here, we provide a structural basis for recognition of TIRs by SETMAR and investigate the function of SETMAR through genome-wide approaches. As elucidated in our 2.37 Å crystal structure, SETMAR forms a dimeric complex with each DNA-binding domain bound specifically to TIRDNA through the formation of 32 hydrogen bonds. We found that SETMAR recognizes primarily TIR sequences (-5000 sites) within the human genome as assessed by chromatin immunoprecipitation sequencing analysis. In two SETMAR KO cell lines, we identified 163 shared differentially expressed genes and 233 shared alternative splicing events. Among these genes are several pre-mRNA-splicing factors, transcription factors, and genes associated with neuronal function, and one alternatively spliced primate-specific gene, TMEM14B, which has been identified as a marker for neocortex expansion associated with brain evolution. Taken together, our results suggest a model in which SETMAR impacts differential expression and alternative splicing of genes associated with transcription and neuronal function, potentially through both its TIR-specific DNA-binding and lysine methyltransferase activities, consistent with a role for SETMAR in simian primate development. [ABSTRACT FROM AUTHOR]

The possibility of substantial offshore wind energy development in the United States (U.S.) is rapidly advancing. Several offshore wind projects have been proposed proximate to federally-recognized tribal territory. Historically marginalized, indigenous communities have for centuries experienced injustices during the expansion of the U.S. energy system. Few studies have systematically examined the responses of indigenous communities to offshore wind, and little is known about the ways that indigenous concerns are leveraged by non-members to advance a position advocating for or against offshore development. In this study, we examine the discourses that surround indigenous communities through legally mandated decision-making processes for two proposed offshore wind projects in the northeast U.S. We show that narratives surrounding indigenous stakeholders in the offshore wind scoping process can be thematically identified as: 1. religious, cultural, and spiritual value , 2. land and identity , and 3. process and procedures. However, the concerns and perspectives of indigenous communities are mostly brought forth by non-group members, and were found to be leveraged or diminished by non-indigenous individuals pushing anti- or pro-offshore wind sentiment. This reveals the finding that indigenous concerns are being co-opted or sidelined through formal and legal decision-making processes in the U.S. The results indicate that the formal consultation process failed to meet standards of energy justice by inadvertently giving outsize voice to lesser impacted communities. Therefore, our study cautions that energy justice is not achieved solely through "inclusive" processes and decision-makers should be diligent in considering the multi-faceted aspects of justice. [ABSTRACT FROM AUTHOR]

Several studies have been performed in the last three decades to assess the impacts of marine biofouling on offshore wind turbines (OWTs) substructures. Marine biofouling generally refers to the settlement and growth of aquatic organisms on human-made structures situated in marine and estuarine environments. OWTs continue to demonstrate significant energy extraction potential and their performance in the ocean is a promising area of research. Most wind turbine installations are in shallow water depths of less than 100 m. At these depths, biofouling can be seen on a large section of cylindrical structures, including mooring lines or power cables, with considerable roughness. This paper provides a review of biofouling phenomena in the context of offshore/marine cylindrical structures. The ecological and social implications of biofouling are reviewed alongside the technical parameters of what is considered to be undesired growth among engineers. The review specifically highlights various marine fouling parameters and laboratory approaches employed by past researchers in modelling biofouling, and the latter's effects on hydrodynamic loading from wave and current excitation. This paper explores challenges in modelling biofouling caused by its intrinsic randomness and uncertainty, as well as suggestions for many studies on marine fouling that are currently absent. • Study of the effect of surface roughness is done under the premise of hard biofouling. • Only a few studies have investigated the impact of soft and lengthy flapping biofouling. • Dependence of biofouling only on surface roughness remains a debated topic. • Ecological effects of biofouling and social preferences for artificial reefs complicate antifouling designs. • Most research rarely considers the effects of fatigue environmental conditions on OWTs substructures. [ABSTRACT FROM AUTHOR]