bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evidence for a Locally Thinned Lithosphere Associated With Recent Volcanism at Aramaiti Corona, Venus
Authors: Russell M. B. , Johnson C. L. 
Published: June 2021

AbstractHeat flow estimates of terrestrial planets and icy satellites are important for exploring their thermal evolution. Topographic signatures of flexure can be used to estimate the effective elastic lithospheric thickness, he, and heat flow. Here, we use high resolution stereo topography and axisymmetric elastic flexure models to investigate lithospheric flexure around Narina Tholus, a steep‐sided volcanic dome ∼40 km across that superposes the tectonic annulus of Aramaiti Corona. Our results indicate a best‐fit elastic thickness he = 3.9–9.1 km, for values of Young's modulus, E, ranging from 65 to 5 GPa respectively. This suggests a thinned lithosphere locally around Narina Tholus, compared to regional estimates for he. The lower values of E are appropriate to the heavily fractured environment of the corona annulus, and we find that they predict flexural stresses compatible with the limited fracturing observed around Narina Tholus. A global survey yielded 13 additional tholi (or tholi groups) at coronae and with stereo coverage, none of which showed evidence for flexure. We find, that locally at Narina Tholus, the heat flow is elevated by a factor of 2–4 relative to that inferred from a previous study of flexure at Aramaiti, consistent with late‐stage, possibly recent, volcanism focused at, and facilitated by, the fracture annulus. Our results further strengthen arguments for a currently volcanically active planet and demonstrate the role that high‐resolution stereo topography can play in elucidating the current thermal state of Venus.
Deep Structure of the Continental Plate in the South‐Central Chilean Margin: Metamorphic Wedge and Implications for Megathrust Earthquakes
Authors: Maksymowicz A. , Contreras‐Reyes E. , Díaz D. , Comte D. , Bangs N. , Tréhu A. M. , Vera E. , Hervé F. , Rietbrock A. 
Published: June 2021

AbstractWe study the deep structure of the continental wedge along the south‐central Chilean convergent margin based on a joint interpretation of wide‐angle reflection and refraction seismic phases acquired between the southern part of the Maule 2010 (36°S) and the northern part of the Valdivia 1960 (41°S) earthquake rupture areas. When combined with results of previous seismic studies, our results provide new insights into the deep structure (to 15–20 km) of the overriding, continental South American plate. We observe a latitudinal variation of P wave velocity, interpreted in terms of the distribution of Permo‐Triassic metamorphic complex near the coast, and deep reflectors at the base of these metamorphic units. A change in the observed deep structural style near 38°S suggests a segmentation in the interplate frictional properties between the Maule and Valdivia earthquakes rupture zones. This regional change in the continental wedge structure indicates a spatial correlation between the coseismic ruptures of large earthquakes (e.g., the 1960 and 2010 megathrust earthquakes) and the rheology/lithology along the interplate boundary.
A Newly Observed Deep Countercurrent in the Subtropical Northwest Pacific
Authors: Azminuddin F. , Jeon D. , Kim Y. H. , Jang C. J. , Park J.‐H. 
Published: June 2021

AbstractThe existence of a deep countercurrent in the subtropical northwest Pacific, named Subtropical Deep Countercurrent (STDCC), has been revealed by moored current‐meter data obtained from a buoy system (∼21.6°N, ∼132.8°E) during 4 years (2010–2014). The climatological average of Argo‐based absolute geostrophic velocities and ocean reanalyzes have further confirmed the spatial picture of the eastward‐flowing STDCC. STDCC is identified as a time‐mean feature in the latitudinal range of 19°–25°N with a meridional scale of 200–300 km that persistently appears from 125° to 180°E and slightly shifts to the north as it goes east. Vertically, STDCC is mostly found below 1,000 m with its core located between the depths of 1,250 and 2,000 m, which corresponds to the undercurrent's meridional pattern with increasing depth northward and a meridional space of 2°–4°. Nevertheless, STDCC is distinctive where it lies along ∼27.6 − , which is deeper than the North Equatorial Undercurrent's density layer (∼27.0 − ). The mean velocity of STDCC at 2,000 m observed by mooring measurements was approximately 0.2 ± 0.15 cm s−1 with a maximum speed of approximately 5.59 cm s−1. The ocean reanalyzes also support the existence of STDCC with mean velocity of approximately 0.2–0.6 cm s−1 west of 145°E and can be as large as 1.6 cm s−1 at the eastern region. The results show that STDCC is closely related to the westward‐propagating eddies. Our finding emphasizes that the convergence of the cyclonic and anticyclonic eddies possibly generates time‐mean zonally elongated eastward flows forming STDCC feature.
Quantifying the Source Term and Uniqueness of the August 12, 2017 Pacific Northwest PyroCb Event
Authors: Fromm M. D. , Kablick G. P. , Peterson D. A. , Kahn R. A. , Flower V. J. B. , Seftor C. J. 
Published: June 2021

AbstractA pyrocumulonimbus (pyroCb) firestorm event known as the Pacific Northwest Event (PNE), on August 12, 2017, is examined with a focus on newly reported details of the pyroconvective injections, transport pathway, and young‐plume altitude. Because PNE and a subsequent pyroCb event in Australia have been compared to classic stratospheric volcanic plumes, a prime motivation for this work was to exhaustively characterize the beginning of PNE, and to show how it compared to major stratospheric plumes from prior events. We find and report direct evidence that PNE pyroconvection involved seven discrete storms, at least two of which injected a plume to at least 13.7 km, up to 2.5 km above the local tropopause. The morning after, stratospheric smoke was observed above the tropopause to altitudes as great as 16 km. We also quantify for the first time that PNE was preceded by a pyroCb injection one day earlier, generating a plume noteworthy on its own but overwhelmed by the PNE smoke. Our comparison of PNE with five earlier pyroCb events reveals that PNE was not distinctive with respect to its injection and nascent plume height. However, it did produce the greatest known ultraviolet absorbing aerosol index and plume longevity as of 2017.
A Spectral Investigation of Aqueously and Thermally Altered CM, CM‐An, and CY Chondrites Under Simulated Asteroid Conditions for Comparison With OSIRIS‐REx and Hayabusa2 Observations
Authors: Bates H. C. , Donaldson Hanna K. L. , King A. J. , Bowles N. E. , Russell S. S. 
Published: June 2021

AbstractVolatile‐rich asteroids are crucial to understanding the transport of water and organics to the terrestrial planet forming region in the early Solar System. Observations of two such asteroids by Hayabusa2 and Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS‐REx) suggest a relationship between these bodies and CI, CM, and CY chondrites. To confirm this, meteorite spectra need to be collected under appropriate conditions for comparison with asteroid observations. We report midinfrared (MIR) emissivity spectra (5.5–50 μm) obtained under ambient and simulated asteroid environment conditions and near‐infrared (NIR) reflectance spectra (2–5 μm) of CM and CY chondrite fine‐particulate (<35 μm) powders for which bulk mineralogy was determined using X‐ray diffraction. Reflectance spectra show a 3 μm feature associated with ‐OH/H2O that shifts from shorter (∼2.72 μm) to longer (∼2.90 μm) wavelengths and develops a rounder shape and reduced band area with increasing thermal metamorphism. In the MIR, the transparency feature (TF) and features in the Si‐O bending region (>15 μm) can be used to infer the relative degree of aqueous alteration, and to resolve the effects of aqueous and thermal alteration, when combined with NIR spectral parameters. The MIR spectra of metamorphosed CY chondrites are distinct from CM chondrite spectra, including a plateau around the Christiansen feature (∼8.00–12.50 μm) and features at longer wavelengths in the Si‐O bending region (e.g., ∼25.50 μm compared to ∼24.30 μm in the CM spectra). We additionally report potential implications of the spectra and parameters determined in this study for the results from Hayabusa2 and OSIRIS‐REx.
YAP inactivation in estrogen receptor alpha-positive hepatocellular carcinoma with less aggressive behavior
Authors: Jeon Youngsic , Yoo Jeong Eun , Rhee Hyungjin , Kim Young-Joo , Il Kim Gwang , Chung Taek , Yoon Sarah , Shin Boram , Woo Hyun Goo , Park Young Nyun 
Published: June 2021

AbstractThe expression of estrogen receptor alpha (ERα, encoded by ESR1) has been shown to be associated with the prognostic outcomes of patients in various cancers; however, its prognostic and mechanistic significance in hepatocellular carcinoma (HCC) remain unclear. Here, we evaluated the expression of ERα and its association with clinicopathological features in 339 HCC patients. ERα was expressed in 9.4% (32/339) of HCCs and was related to better overall survival (OS; hazard ratio [HR] = 0.11, p = 0.009, 95% C.I. = 0.016–0.82) and disease-free survival (DFS, HR = 0.4, p = 0.013, 95% C.I. = 0.18–0.85). ERα expression was also associated with features related to more favorable prognosis, such as older age, lower serum alpha-fetoprotein level, and less microvascular invasion (p < 0.05). In addition, to obtain mechanistic insights into the role of ERα in HCC progression, we performed integrative transcriptome data analyses, which revealed that yes-associated protein (YAP) pathway was significantly suppressed in ESR1-expressing HCCs. By performing cell culture experiments, we validated that ERα expression enhanced YAP phosphorylation, attenuating its nuclear translocation, which in turn suppressed the downstream signaling pathways and cancer cell growth. In conclusion, we suggest that ERα expression is an indicator of more favorable prognosis in HCC and that this effect is mediated by inactivation of YAP signaling. Our results provide new clinical and pathobiological insights into ERα and YAP signaling in HCC.
Evolution of the cytochrome bd oxygen reductase superfamily and the function of CydAA’ in Archaea
Authors: Murali Ranjani , Gennis Robert B , Hemp James 
Published: June 2021

Abstract
Cytochrome bd-type oxygen reductases (cytbd) belong to one of three enzyme superfamilies that catalyze oxygen reduction to water. They are widely distributed in Bacteria and Archaea, but the full extent of their biochemical diversity is unknown. Here we used phylogenomics to identify three families and several subfamilies within the cytbd superfamily. The core architecture shared by all members of the superfamily consists of four transmembrane helices that bind two active site hemes, which are responsible for oxygen reduction. While previously characterized cytochrome bd-type oxygen reductases use quinol as an electron donor to reduce oxygen, sequence analysis shows that only one of the identified families has a conserved quinol binding site. The other families are missing this feature, suggesting that they use an alternative electron donor. Multiple gene duplication events were identified within the superfamily, resulting in significant evolutionary and structural diversity. The CydAA’ cytbd, found exclusively in Archaea, is formed by the co-association of two superfamily paralogs. We heterologously expressed CydAA’ from Caldivirga maquilingensis and demonstrated that it performs oxygen reduction with quinol as an electron donor. Strikingly, CydAA’ is the first isoform of cytbd containing only b-type hemes shown to be active when isolated from membranes, demonstrating that oxygen reductase activity in this superfamily is not dependent on heme d.
Mechanisms driving genome reduction of a novel Roseobacter lineage
Authors: Feng Xiaoyuan , Chu Xiao , Qian Yang , Henson Michael W , Lanclos V Celeste , Qin Fang , Barnes Shelby , Zhao Yanlin , Thrash J Cameron , Luo Haiwei 
Published: June 2021

Summary
Members of the marine Roseobacter group are key players in the global carbon and sulfur cycles. While over 300 species have been described, only 2% possess reduced genomes (mostly 3–3.5 Mbp) compared to an average roseobacter (&gt;4 Mbp). These taxonomic minorities are phylogenetically diverse but form a Pelagic Roseobacter Cluster (PRC) at the genome content level. Here, we cultivated eight isolates constituting a novel Roseobacter lineage which we named ‘CHUG’. Metagenomic and metatranscriptomic read recruitment analyses showed that CHUG members are globally distributed and active in marine pelagic environments. CHUG members possess some of the smallest genomes (~2.6 Mb) among all known roseobacters, but they do not exhibit canonical features of typical bacterioplankton lineages theorized to have undergone genome streamlining processes, like higher coding density, fewer paralogues and rarer pseudogenes. While CHUG members form a genome content cluster with traditional PRC members, they show important differences. Unlike other PRC members, neither the relative abundances of CHUG members nor their relative gene expression levels are correlated with chlorophyll a concentration across the global samples. CHUG members cannot utilize most phytoplankton-derived metabolites or synthesize vitamin B12, a key metabolite mediating the roseobacter-phytoplankton interactions. This combination of features is evidence for the hypothesis that CHUG members may have evolved a free-living lifestyle decoupled from phytoplankton. This ecological transition was accompanied by the loss of signature genes involved in roseobacter-phytoplankton symbiosis, suggesting that relaxation of purifying selection owing to lifestyle shift is likely an important driver of genome reduction in CHUG.
Circular RNA AFF4 modulates osteogenic differentiation in BM-MSCs by activating SMAD1/5 pathway through miR-135a-5p/FNDC5/Irisin axis
Authors: Liu Chao , Liu An-Song , Zhong Da , Wang Cheng-Gong , Yu Mi , Zhang Hao-Wei , Xiao Han , Liu Jian-Hua , Zhang Jian , Yin Ke 
Published: June 2021

AbstractBone marrow-derived mesenchymal stem cells (BM-MSCs), the common progenitor cells of adipocytes and osteoblasts, have been recognized as the key mediator during bone formation. Herein, our study aim to investigate molecular mechanisms underlying circular RNA (circRNA) AFF4 (circ_AFF4)-regulated BM-MSCs osteogenesis. BM-MSCs were characterized by FACS, ARS, and ALP staining. Expression patterns of circ_AFF4, miR-135a-5p, FNDC5/Irisin, SMAD1/5, and osteogenesis markers, including ALP, BMP4, RUNX2, Spp1, and Colla1 were detected by qRT-PCR, western blot, or immunofluorescence staining, respectively. Interactions between circ_AFF4 and miR-135a-5p, FNDC5, and miR-135a-5p were analyzed using web tools including TargetScan, miRanda, and miRDB, and further confirmed by luciferase reporter assay and RNA pull-down. Complex formation between Irisin and Integrin αV was verified by Co-immunoprecipitation. To further verify the functional role of circ_AFF4 in vivo during bone formation, we conducted animal experiments harboring circ_AFF4 knockdown, and born samples were evaluated by immunohistochemistry, hematoxylin and eosin, and Masson staining. Circ_AFF4 was upregulated upon osteogenic differentiation induction in BM-MSCs, and miR-135a-5p expression declined as differentiation proceeds. Circ_AFF4 knockdown significantly inhibited osteogenesis potential in BM-MSCs. Circ_AFF4 stimulated FNDC5/Irisin expression through complementary binding to its downstream target molecule miR-135a-5p. Irisin formed an intermolecular complex with Integrin αV and activated the SMAD1/5 pathway during osteogenic differentiation. Our work revealed that circ_AFF4, acting as a sponge of miR-135a-5p, triggers the promotion of FNDC5/Irisin via activating the SMAD1/5 pathway to induce osteogenic differentiation in BM-MSCs. These findings gained a deeper insight into the circRNA-miRNA regulatory system in the bone marrow microenvironment and may improve our understanding of bone formation-related diseases at physiological and pathological levels.
Hypoxic postconditioning promotes mitophagy against transient global cerebral ischemia via PINK1/Parkin-induced mitochondrial ubiquitination in adult rats
Authors: Wen Haixia , Li Luxi , Zhan Lixuan , Zuo Yunyan , Li Kongping , Qiu Meiqian , Li Heying , Sun Weiwen , Xu En 
Published: June 2021

AbstractMitophagy alleviates neuronal damage after cerebral ischemia by selectively removing dysfunctional mitochondria. Phosphatase and tensin homolog (PTEN) induced putative kinase 1 (PINK1)/Parkin-mediated mitophagy is the most well-known type of mitophagy. However, little is known about the role of PINK1/Parkin-mediated mitophagy in ischemic tolerance induced by hypoxic postconditioning (HPC) with 8% O2 against transient global cerebral ischemia (tGCI). Hence, we aimed to test the hypothesis that HPC-mediated PINK1/Parkin-induced mitochondrial ubiquitination and promotes mitophagy, thus exerting neuroprotection in the hippocampal CA1 subregion against tGCI. We found that mitochondrial clearance was disturbed at the late phase of reperfusion after tGCI, which was reversed by HPC, as evidenced by the reduction of the translocase of outer mitochondrial membrane 20 homologs (TOMM20), translocase of inner mitochondrial membrane 23 (TIMM23) and heat shock protein 60 (HSP60) in CA1 after HPC. In addition, HPC further increased the ratio of LC3II/I in mitochondrial fraction and promoted the formation of mitophagosomes in CA1 neurons after tGCI. The administration of lysosome inhibitor chloroquine (CQ) intraperitoneally or mitophagy inhibitor (Mdivi-1) intracerebroventricularly abrogated HPC-induced mitochondrial turnover and neuroprotection in CA1 after tGCI. We also found that HPC activated PINK1/Parkin pathway after tGCI, as shown by the augment of mitochondrial PINK1 and Parkin and the promotion of mitochondrial ubiquitination in CA1. In addition, PINK1 or Parkin knockdown with small-interfering RNA (siRNA) suppressed the activation of PINK1/Parkin pathway and hampered mitochondrial clearance and attenuated neuroprotection induced by HPC, whereas PINK1 overexpression promoted PINK1/Parkin-mediated mitophagy and ameliorated neuronal damage in CA1 after tGCI. Taken together, the new finding in this study is that HPC-induced neuroprotection against tGCI through promoting mitophagy mediated by PINK1/Parkin-dependent pathway.
Circ_0008542 in osteoblast exosomes promotes osteoclast-induced bone resorption through m6A methylation
Authors: Wang Wei , Qiao Shi-Chong , Wu Xiang-Bing , Sun Bao , Yang Jin-Gang , Li Xing , Zhang Xiao , Qian Shu-Jiao , Gu Ying-Xin , Lai Hong-Chang 
Published: June 2021

AbstractWith an increasing aging society, China is the world’s fastest growing markets for oral implants. Compared with traditional oral implants, immediate implants cause marginal bone resorption and increase the failure rate of osseointegration, but the mechanism is still unknown. Therefore, it is important to further study mechanisms of tension stimulus on osteoblasts and osteoclasts at the early stage of osseointegration to promote rapid osseointegration around oral implants. The results showed that exosomes containing circ_0008542 from MC3T3-E1 cells with prolonged tensile stimulation promoted osteoclast differentiation and bone resorption. Circ_0008542 upregulated Tnfrsf11a (RANK) gene expression by acting as a miR-185-5p sponge. Meanwhile, the circ_0008542 1916-1992 bp segment exhibited increased m6A methylation levels. Inhibiting the RNA methyltransferase METTL3 or overexpressing the RNA demethylase ALKBH5 reversed osteoclast differentiation and bone resorption induced by circ_0008542. Injection of circ_0008542 + ALKBH5 into the tail vein of mice reversed the same effects in vivo. Site-directed mutagenesis study demonstrated that 1956 bp on circ_0008542 is the m6A functional site with the abovementioned biological functions. In conclusion, the RNA methylase METTL3 acts on the m6A functional site of 1956 bp in circ_0008542, promoting competitive binding of miRNA-185-5p by circ_0008542, and leading to an increase in the target gene RANK and the initiation of osteoclast bone absorption. In contrast, the RNA demethylase ALKBH5 inhibits the binding of circ_0008542 with miRNA-185-5p to correct the bone resorption process. The potential value of this study provides methods to enhance the resistance of immediate implants through use of exosomes releasing ALKBH5.
A chromosome-level genome assembly of rugged rose (Rosa rugosa) provides insights into its evolution, ecology, and floral characteristics
Authors: Chen Fei , Su Liyao , Hu Shuaiya , Xue Jia-Yu , Liu Hui , Liu Guanhua , Jiang Yifan , Du Jianke , Qiao Yushan , Fan Yannan , Liu Huan , Yang Qi , Lu Wenjie , Shao Zhu-Qing , Zhang Jian , Zhang Liangsheng , Chen Feng , Cheng Zong-Ming 
Published: June 2021

AbstractRosa rugosa, commonly known as rugged rose, is a perennial ornamental shrub. It produces beautiful flowers with a mild fragrance and colorful seed pods. Unlike many other cultivated roses, R. rugosa adapts to a wide range of habitat types and harsh environmental conditions such as salinity, alkaline, shade, drought, high humidity, and frigid temperatures. Here, we produced and analyzed a high-quality genome sequence for R. rugosa to understand its ecology, floral characteristics and evolution. PacBio HiFi reads were initially used to construct the draft genome of R. rugosa, and then Hi-C sequencing was applied to assemble the contigs into 7 chromosomes. We obtained a 382.6 Mb genome encoding 39,704 protein-coding genes. The genome of R. rugosa appears to be conserved with no additional whole-genome duplication after the gamma whole-genome triplication (WGT), which occurred ~100 million years ago in the ancestor of core eudicots. Based on a comparative analysis of the high-quality genome assembly of R. rugosa and other high-quality Rosaceae genomes, we found a unique large inverted segment in the Chinese rose R. chinensis and a retroposition in strawberry caused by post-WGT events. We also found that floral development- and stress response signaling-related gene modules were retained after the WGT. Two MADS-box genes involved in floral development and the stress-related transcription factors DREB2A-INTERACTING PROTEIN 2 (DRIP2) and PEPTIDE TRANSPORTER 3 (PTR3) were found to be positively selected in evolution, which may have contributed to the unique ability of this plant to adapt to harsh environments. In summary, the high-quality genome sequence of R. rugosa provides a map for genetic studies and molecular breeding of this plant and enables comparative genomic studies of Rosa in the near future.
A Japanese adult and two girls with NEDMIAL caused by de novo missense variants in DHX30
Authors: Ueda Kimiko , Araki Atsushi , Fujita Atsushi , Matsumoto Naomichi , Uehara Tomoko , Suzuki Hisato , Takenouchi Toshiki , Kosaki Kenjiro , Okamoto Nobuhiko 
Published: June 2021

AbstractLessel et al. reported a novel neurodevelopmental disorder with severe motor impairment and absent language (NEDMIAL) in 12 individuals and identified six different de novo heterozygous missense variants in DHX30. The other clinical features included muscular hypotonia, feeding difficulties, brain anomalies, autistic features, sleep disturbances, and joint hypermobility. We report a Japanese adult with a novel missense variant and two girls with de novo missense variants in DHX30.