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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]

Abstract: An overview is presented of some of the recent results concerning the suitability of Czochralski silicon to High Energy Physics (HEP) radiation detectors. It has been shown that an elevated oxygen concentration within the bulk silicon of detectors offers increased radiation hardness to charged particle radiation. Silicon produced using the Czochralski growth method has an intrinsically higher concentration of oxygen than the standard silicon growth method, float zone, which is extensively used in HEP radiation detectors. The research reviewed in this paper aims to understand the microscopic and macroscopic behaviour of Czochralski and compares the performance to standard silicon radiation detectors. The majority of this work has been performed in the framework of the RD50 collaboration. [Copyright &y& Elsevier]

Abstract: Magnetic Czochralski (MCz) silicon has recently become a promising material for the development of radiation tolerant detectors for future high-luminosity HEP experiments. A thorough study of 24GeV/c proton-irradiated p+-in-n Float Zone (FZ) , Diffusion Oxygenated Float Zone (DOFZ) and MCz silicon detectors has been conducted using the standard radiation damage characterization tools IV and CV, the Transient Current Technique (TCT) and annealing studies. The first systematic study on the effective trapping time in MCz silicon has been performed. The results show that the introduction rate for the traps responsible for the degradation of the effective trapping time for MCz material agrees with the introduction rate for FZ and DOFZ silicon. From the behaviour of the depletion voltage as a function of proton fluence and through the TCT technique, it has been shown that by a radiation fluence of 5×1014 p/cm2 the depletion voltage has passed its minimum value without type inversion. An annealing study compares the evolution of the effective trapping time, the effective space charge density and the current-related damage parameters for MCz and DOFZ silicon. [Copyright &y& Elsevier]

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]

KCNQ1 (Kv7.1 or KvLQT1) is a voltage-gated potassium ion channel that is involved in the ventricular repolarization following an action potential in the heart. It forms a complex with KCNE1 in the heart and is the pore forming subunit of slow delayed rectifier potassium current (I ks). Mutations in KCNQ1, leading to a dysfunctional channel or loss of activity have been implicated in a cardiac disorder, long QT syndrome. In this study, we report the overexpression, purification, biochemical characterization of human KCNQ1 100 – 370 , and lipid bilayer dynamics upon interaction with KCNQ1 100 – 370. The recombinant human KCNQ1 was expressed in Escherichia coli and purified into n-dodecylphosphocholine (DPC) micelles. The purified KCNQ1 100 – 370 was biochemically characterized by SDS-PAGE electrophoresis, western blot and nano-LC-MS/MS to confirm the identity of the protein. Circular dichroism (CD) spectroscopy was utilized to confirm the secondary structure of purified protein in vesicles. Furthermore, 31P and 2H solid-state NMR spectroscopy in DPPC/POPC/POPG vesicles (MLVs) indicated a direct interaction between KCNQ 100 – 370 and the phospholipid head groups. Finally, a visual inspection of KCNQ1 100 – 370 incorporated into MLVs was confirmed by transmission electron microscopy (TEM). The findings of this study provide avenues for future structural studies of the human KCNQ1 ion channel to have an in depth understanding of its structure-function relationship. [Display omitted] • Purification of KCNQ1 potassium ion channel • Probing the interaction of KCNQ1 with the membrane using solid-state NMR spectroscopic techniques • Secondary structural characteristics of KCNQ1 [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]

In mammalian cells, specific aminoacyl-transfer RNA (tRNA) synthetases have cytokine functions that require interactions with partners outside of the translation apparatus. Little is known about these interactions and how they facilitate expanded functions that link protein translation to other cellular pathways. For example, an alternative splice fragment of tryptophanyl-tRNA synthetase (TrpRS) and a similar natural proteolytic fragment are potent angiostatic factors that act through the vascular endothelial-cadherin receptor and Akt signaling pathway. Here we demonstrate mobilization of TrpRS for exocytosis from endothelial cells and the potential for plasmin to activate the cytokine function of the extracellular synthetase. Direct physical evidence showed that the annexin II-S100A10 complex, which regulates exocytosis, forms a ternary complex with TrpRS. Functional studies demonstrate that both annexin II and S100A10 regulate trafficking of TrpRS. Thus, complexes of mammalian tRNA synthetases with seemingly disparate proteins may in general be relevant to understanding how their expanded functions are implemented. [ABSTRACT FROM AUTHOR]