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The Hikurangi Margin (HM) is a subduction zone along the east coast of the North Island of New Zealand where varying instances of slow slip events (SSEs) and earthquakes occur. These SSEs occur at different time scales and depths when comparing the northern and southern ends of the margin. Previous studies show that the rock comprising the accretionary wedge of the northern margin have low permeabilities, which could induce overpressures and modulate the occurrence of SSEs. Permeability rises when an SSE fractures the rocks within the deep wedge promoting fluid flow and thus dissipating the overpressures along and above the décollement. As fractures heal and permeability recovers overpressures build up once again. Although this cycle may explain the occurrence of SSEs along northern Hikurangi, it is not yet clear how intrinsic permeability varies in rocks above the décollement elsewhere along the margin. To better understand the disparity in SSE occurrence, rock samples from the northern and central part of the margin have been tested for permeability and elastic properties. We tested samples from the Weber, Whangai, Dannevirke and Wanstead formations, which are representative of the lithologies above the décollement in the central margin, and range in age from the Cretaceous to the mid to late Paleogene. We found that the Weber (PQ) and Whangai (PO) formation samples from central HM have higher permeability than northern HM rocks from the same formation in the north. This study provides insight into the mechanisms that lead to significantly fewer SSEs along the central HM. In the near future, we plan to conduct a suite of physical experiments that will include permeability recovery after fracturing, compaction, and ultrasonic velocity analysis to help further understand the stark differences in slip behavior observed along the margin. 

Description of endMT abnormalities and abnormal response to flow in TS iPSC-ECs 

Hybrid complexes incorporating synthetic Mn-porphyrins into an artificial four-helix bundle domain of bacterial reaction centers created a system to investigate new electron transfer pathways. The reactions were initiated by illumination of the bacterial reaction centers, whose primary photochemistry involves electron transfer from the bacteriochlorophyll dimer through a series of electron acceptors to the quinone electron acceptors. Porphyrins with diphenyl, dimesityl, or fluorinated substituents were synthesized containing either Mn or Zn. Electrochemical measurements revealed potentials for Mn(III)/Mn(II) transitions that are ~ 0.4 V higher for the fluorinated Mn-porphyrins than the diphenyl and dimesityl Mn-porphyrins. The synthetic porphyrins were introduced into the proteins by binding to a four-helix bundle domain that was genetically fused to the reaction center. Light excitation of the bacteriochlorophyll dimer of the reaction center resulted in new derivative signals, in the 400 to 450 nm region of light-minus-dark spectra, that are consistent with oxidation of the fluorinated Mn(II) porphyrins and reduction of the diphenyl and dimesityl Mn(III) porphyrins. These features recovered in the dark and were not observed in the Zn(II) porphyrins. The amplitudes of the signals were dependent upon the oxidation/reduction midpoint potentials of the bacteriochlorophyll dimer. These results are interpreted as photo-induced charge-separation processes resulting in redox changes of the Mn-porphyrins, demonstrating the utility of the hybrid artificial reaction center system to establish design guidelines for novel electron transfer reactions. 

Abstract Clinopyroxene is a rock-forming mineral that commonly hosts melt inclusions in mafic to intermediate composition volcanic and plutonic rocks. It is highly resistant to alteration compared to other co-existing phenocrysts such as plagioclase. Several recent studies have 40Ar/39Ar dated clinopyroxene in Neoproterozoic to Miocene basalts and dolerites. To assess the viability of the technique at the youngest end of the geologic time scale, we performed 40Ar/39Ar incremental heating experiments on clinopyroxene-hosted melt inclusions from a variety of mafic lithologies and tectonic settings. Most samples produced precise plateau ages including several Quaternary basalts to andesites as young as 0.6 Ma. All data are indistinguishable from new and/or published 40Ar/39Ar ages on groundmass or plagioclase from the same samples. The source of potassium (K) and resulting 40Ar* within clinopyroxene has been debated, but thus far has only been inferred based on 40Ar/39Ar data. Using electron probe microanalysis (EPMA) we show that there is negligible K in the clinopyroxene host, but substantial K (e.g., 1–4 wt%) in trapped melt inclusions and minor amounts in plagioclase inclusions. Thus, melt inclusions, which are common in phenocrysts in basaltic magmas, can be used to obtain accurate and precise 40Ar/39Ar ages for difficult-to-date volcanic and plutonic rocks from the Precambrian to the Pleistocene. 

In this related paper set, our goal was to advance a more holistic vision of equity and social justice in science, technology, engineering, and mathematics (STEM) education by drawing attention to an often-overlooked social asset for learners—their families. While families are usually secondary in discussions of equity in STEM education, a growing number of researchers have highlighted the need to consider and partner with families to establish anti-racist, asset-based educational practices in both informal and formal learning environments. In this related paper set, the first two papers directly challenge the ways deficit-based perceptions of families from historically marginalized communities undermine the critical role that family members play in supporting youth STEM engagement, learning, and identity development. In the second two papers, investigators examine how educators and researchers can use insights from families to inform the design of learning environments inside and outside of school. Collectively, the four papers emphasize the critical importance of working with families to address inequities in STEM education and demonstrate the unique opportunities for envisioning new learning possibilities through these partnerships. 

In this related paper set, our goal was to advance a more holistic vision of equity and social justice in science, technology, engineering, and mathematics (STEM) education by drawing attention to an often-overlooked social asset for learners—their families. While families are usually secondary in discussions of equity in STEM education, a growing number of researchers have highlighted the need to consider and partner with families to establish anti-racist, asset-based educational practices in both informal and formal learning environments. In this related paper set, the first two papers directly challenge the ways deficit-based perceptions of families from historically marginalized communities undermine the critical role that family members play in supporting youth STEM engagement, learning, and identity development. In the second two papers, investigators examine how educators and researchers can use insights from families to inform the design of learning environments inside and outside of school. Collectively, the four papers emphasize the critical importance of working with families to address inequities in STEM education and demonstrate the unique opportunities for envisioning new learning possibilities through these partnerships. 

Abstract Background The function of DNA methyltransferase genes of insects is a puzzle, because an association between gene expression and methylation is not universal for insects. If the genes normally involved in cytosine methylation are not influencing gene expression, what might be their role? We previously demonstrated that gametogenesis of Oncopeltus fasciatus is interrupted at meiosis following knockdown of DNA methyltransferase 1 ( Dnmt1 ) and this is unrelated to changes in levels of cytosine methylation. Here, using transcriptomics, we tested the hypothesis that Dmnt1 is a part of the meiotic gene pathway. Testes, which almost exclusively contain gametes at varying stages of development, were sampled at 7 days and 14 days following knockdown of Dmnt1 using RNAi. Results Using microscopy, we found actively dividing spermatocysts were reduced at both timepoints. However, as with other studies, we saw Dnmt1 knockdown resulted in condensed nuclei after mitosis–meiosis transition, and then cellular arrest. We found limited support for a functional role for Dnmt1 in our predicted cell cycle and meiotic pathways. An examination of a priori Gene Ontology terms showed no enrichment for meiosis. We then used the full data set to reveal further candidate pathways influenced by Dnmt1 for further hypotheses. Very few genes were differentially expressed at 7 days, but nearly half of all transcribed genes were differentially expressed at 14 days. We found no strong candidate pathways for how Dnmt1 knockdown was achieving its effect through Gene Ontology term overrepresentation analysis. Conclusions We, therefore, suggest that Dmnt1 plays a role in chromosome dynamics based on our observations of condensed nuclei and cellular arrest with no specific molecular pathways disrupted.