bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Maximum Rupture Model for the Southern San Andreas and San Jacinto Faults, California, Derived From Paleoseismic Earthquake Ages: Observations and Limitations
Authors: Scharer Katherine M. , Yule Doug 
Published: July 2020

AbstractPaleoseismic rupture histories provide spatiotemporal models of earthquake moment release needed to test numerical models and lengthen the instrumental catalog. We develop a model of the fewest and thus largest magnitude earthquakes permitted by paleoseismic data for the last 1,500 years on the southern San Andreas and San Jacinto Faults, California, USA. The largest geometric complexity appears to regulate the system: Only two ruptures break the San Gorgonio Pass region, followed by episodes of ruptures that could bridge the northern San Jacinto Fault and the San Andreas Fault. When tested against independent data on slip per event, the model produces comparable values indicating the end‐member model does not underpredict rupture rates. Rupture of >85% of the fault length in the historic period between 1800 and 1857 and the subsequent quiescence is similar to epochs of activity in the prehistoric model, suggesting that regional clustering of seismicity could be a trait of the system.
Global Survey of Plasma Sheet Electron Precipitation due to Whistler Mode Chorus Waves in Earth's Magnetosphere
Authors: Ma Q. , Connor H. K. , Zhang X.‐J. , Li W. , Shen X.‐C. , Gillespie D. , Kletzing C. A. , Kurth W. S. , Hospodarsky G. B. , Claudepierre S. G. , Reeves G. D. , Spence H. E. 
Published: July 2020

AbstractWhistler mode chorus waves can scatter plasma sheet electrons into the loss cone and produce the Earth's diffuse aurora. Van Allen Probes observed plasma sheet electron injections and intense chorus waves on 24 November 2012. We use quasilinear theory to calculate the precipitating electron fluxes, demonstrating that the chorus waves could lead to high differential energy fluxes of precipitating electrons with characteristic energies of 10–30 keV. Using this method, we calculate the precipitating electron flux from 2012 to 2019 when the Van Allen Probes were near the magnetic equator and perform global surveys of electron precipitation under different geomagnetic conditions. The most significant electron precipitation due to chorus is found from the nightside to dawn sectors over 4 < L < 6.5. The average total precipitating energy flux is enhanced during disturbed conditions, with time‐averaged values reaching ~3–10 erg/cm2/s when AE ≥ 500 nT.
Comprehensive characterization of claudin-low breast tumors reflects the impact of the cell-of-origin on cancer evolution
Authors: Pommier Roxane M. , Sanlaville Amélien , Tonon Laurie , Kielbassa Janice , Thomas Emilie , Ferrari Anthony , Sertier Anne-Sophie , Hollande Frédéric , Martinez Pierre , Tissier Agnès , Morel Anne-Pierre , Ouzounova Maria , Puisieux Alain 
Published: July 2020

AbstractClaudin-low breast cancers are aggressive tumors defined by the low expression of key components of cellular junctions, associated with mesenchymal and stemness features. Although they are generally considered as the most primitive breast malignancies, their histogenesis remains elusive. Here we show that this molecular subtype of breast cancers exhibits a significant diversity, comprising three main subgroups that emerge from unique evolutionary processes. Genetic, gene methylation and gene expression analyses reveal that two of the subgroups relate, respectively, to luminal breast cancers and basal-like breast cancers through the activation of an EMT process over the course of tumor progression. The third subgroup is closely related to normal human mammary stem cells. This unique subgroup of breast cancers shows a paucity of genomic aberrations and a low frequency of TP53 mutations, supporting the emerging notion that the intrinsic properties of the cell-of-origin constitute a major determinant of the genetic history of tumorigenesis.
Symmetry-enforced Weyl phonons
Authors: Liu Qing-Bo , Qian Yuting , Fu Hua-Hua , Wang Zhijun 
Published: July 2020

AbstractIn spinful electronic systems, time-reversal symmetry makes that all Kramers pairs at the time-reversal-invariant momenta are Weyl points (WPs) in chiral crystals. Here, we find that such symmetry-enforced WPs can also emerge in bosonic systems (e.g. phonons and photons) due to nonsymmorphic symmetries. We demonstrate that for some nonsymmorphic chiral space groups, several high-symmetry k-points can host only WPs in the phononic systems, dubbed symmetry-enforced Weyl phonons (SEWPs). The SEWPs, enumerated in Table 1, are pinned at the boundary of the three-dimensional (3D) Brillouin zone (BZ) and protected by nonsymmorphic crystal symmetries. By performing first-principles calculations and symmetry analysis, we propose that as an example of SEWPs, the twofold degeneracies at P are monopole WPs in K2Sn2O3 with space group 199. The two WPs of the same chirality at two nonequivalent P points are related by time-reversal symmetry. In particular, at ~17.5 THz, a spin-1 Weyl phonon is also found at H, since two Weyl phonons at P carrying a non-zero net Chern number cannot exist alone in the 3D BZ. The significant separation between P and H points makes the surface arcs long and clearly visible. Our findings not only present an effective way to search for WPs in bosonic systems, but also offer some promising candidates for studying monopole Weyl and spin-1 Weyl phonons in realistic materials.
Strong structural occupation ratio effect on mechanical properties of silicon carbide nanowires
Authors: Zhang Xuejiao , Wang Jing , Yang Zhenyu , Tang Xuke , Yue Yonghai 
Published: July 2020

AbstractMaterials’ mechanical properties highly depend on their internal structures. Designing novel structure is an effective route to improve materials’ performance. One-dimensional disordered (ODD) structure is a kind of particular structure in silicon carbide (SiC), which highly affects its mechanical properties. Herein, we show that SiC nanowires (NWs) containing ODD structure (with an occupation ratio of 32.6%) exhibit ultrahigh tensile strength and elastic strain, which are up to 13.7 GPa and 12% respectively, approaching the ideal theoretical limit. The ODD structural occupation ratio effect on mechanical properties of SiC NWs has been systematically studied and a saddle shaped tendency for the strength versus occupation ratio is firstly revealed. The strength increases with the increase of the ODD occupation ratio but decreases when the occupation ratio exceeds a critical value of ~ 32.6%, micro twins appear in the ODD region when the ODD segment increases and soften the ODD segment, finally results in a decrease of the strength.
Wireless monitoring and real-time adaptive predictive indicator of deterioration
Authors: Duncan Heather P. , Fule Balazs , Rice Iain , Sitch Alice J. , Lowe David 
Published: July 2020

AbstractTo assist in the early warning of deterioration in hospitalised children we studied the feasibility of collecting continuous wireless physiological data using Lifetouch (ECG-derived heart and respiratory rate) and WristOx2 (pulse-oximetry and derived pulse rate) sensors. We compared our bedside paediatric early warning (PEW) score and a machine learning automated approach: a Real-time Adaptive Predictive Indicator of Deterioration (RAPID) to identify children experiencing significant clinical deterioration. 982 patients contributed 7,073,486 min during 1,263 monitoring sessions. The proportion of intended monitoring time was 93% for Lifetouch and 55% for WristOx2. Valid clinical data was 63% of intended monitoring time for Lifetouch and 50% WristOx2. 29 patients experienced 36 clinically significant deteriorations. The RAPID Index detected significant deterioration more frequently (77% to 97%) and earlier than the PEW score ≥ 9/26. High sensitivity and negative predictive value for the RAPID Index was associated with low specificity and low positive predictive value. We conclude that it is feasible to collect clinically valid physiological data wirelessly for 50% of intended monitoring time. The RAPID Index identified more deterioration, before the PEW score, but has a low specificity. By using the RAPID Index with a PEW system some life-threatening events may be averted.
Simplified modeling of E. coli mortality after genome damage induced by UV-C light exposure
Authors: Sánchez-Navarrete Jaime , Ruiz-Pérez Nancy Jannet , Guerra-Trejo Armando , Toscano-Garibay Julia Dolores 
Published: July 2020

AbstractUV light is a group of high-energy waves from the electromagnetic spectrum. There are three types of UV radiations: UV-A, -B and -C. UV-C light are the highest in energy, but most are retained by the ozone layer. UV-A and -B reach the earth’s surface and cause damage on living organisms, being considered as mutagenic physical agents. Numerous test models are used to study UV mutagenicity; some include special lamps, cell cultures and mathematical modeling. Mercury lamps are affordable and useful sources of UV-C light due to their emission at near the maximum absorption peak of nucleic acids. E. coli cultures are widely used because they have DNA-damage and -repairing mechanisms fairly similar to humans. In here we present two simple models that describe UV-C light incidence on a genome matrix, using fundamental quantum–mechanical concepts and considering light as a particle with a discontinuous distribution. To test the accuracy of our equations, stationary phase cultures of several E. coli strains were exposed to UV-C light in 30 s-intervals. Surviving CFUs were counted and survival/mortality curves were constructed. These graphs adjusted with high goodness of fit to the regression predictions. Results were also analyzed using three main parameters: quantum yield, specific speed and time of mortality.
Environmental enrichment during forced abstinence from cocaine self-administration opposes gene network expression changes associated with the incubation effect
Authors: Powell Gregory L. , Vannan Annika , Bastle Ryan M. , Wilson Melissa A. , Dell’Orco Michela , Perrone-Bizzozero Nora I. , Neisewander Janet L. 
Published: July 2020

AbstractEnvironmental enrichment (EE) is a robust intervention for reducing cocaine-seeking behaviors in animals when given during forced abstinence. However, the mechanisms that underlie these effects are not well-established. We investigated the adult male rat transcriptome using RNA-sequencing (RNA-seq) following differential housing during forced abstinence from cocaine self-administration for either 1 or 21 days. Enriched, 21-day forced abstinence rats displayed a significant reduction in cocaine-seeking behavior compared to rats housed in isolation. RNA-seq of the nucleus accumbens shell revealed hundreds of differentially regulated transcripts between rats of different forced abstinence length and housing environment, as well as within specific contrasts such as enrichment (isolated 21 days vs. enriched 21 days) or incubation (isolated 1 day vs. isolated 21 days). Ingenuity Pathway Analysis affirmed several pathways as differentially enriched based on housing condition and forced abstinence length including RELN, the Eif2 signaling pathway, synaptogenesis and neurogenesis pathways. Numerous pathways showed upregulation with incubation, but downregulation with EE, suggesting that EE may prevent or reverse changes in gene expression associated with protracted forced abstinence. The findings reveal novel candidate mechanisms involved in the protective effects of EE against cocaine seeking, which may inform efforts to develop pharmacological and gene therapies for treating cocaine use disorders. Furthermore, the finding that EE opposes multiple pathway changes associated with incubation of cocaine seeking strongly supports EE as a therapeutic intervention and suggests EE is capable of preventing or reversing the widespread dysregulation of signaling pathways that occurs during cocaine forced abstinence.
Mutational analysis of the essential lipopolysaccharide-transport protein LptH of Pseudomonas aeruginosa to uncover critical oligomerization sites
Authors: Scala Romina , Di Matteo Adele , Coluccia Antonio , Lo Sciuto Alessandra , Federici Luca , Travaglini-Allocatelli Carlo , Visca Paolo , Silvestri Romano , Imperi Francesco 
Published: July 2020

AbstractLipopolysaccharide (LPS) is a critical component of the outer membrane (OM) of many Gram-negative bacteria. LPS is translocated to the OM by the LPS transport (Lpt) system. In the human pathogen Pseudomonas aeruginosa, the periplasmic Lpt component, LptH, is essential for LPS transport, planktonic and biofilm growth, OM stability and infectivity. LptH has been proposed to oligomerize and form a protein bridge that accommodates LPS during transport. Based on the known LptH crystal structure, here we predicted by in silico modeling five different sites likely involved in LptH oligomerization. The relevance of these sites for LptH activity was verified through plasmid-mediated expression of site-specific mutant proteins in a P. aeruginosa lptH conditional mutant. Complementation and protein expression analyses provided evidence that all mutated sites are important for LptH activity in vivo. It was observed that the lptH conditional mutant overcomes the lethality of nonfunctional lptH variants through RecA-mediated homologous recombination between the wild-type lptH gene in the genome and mutated copies in the plasmid. Finally, biochemical assays on purified recombinant proteins showed that some LptH variants are indeed specifically impaired in oligomerization, while others appear to have defects in protein folding and/or stability.
Disturbance history can increase functional stability in the face of both repeated disturbances of the same type and novel disturbances
Authors: Renes Sophia Elise , Sjöstedt Johanna , Fetzer Ingo , Langenheder Silke 
Published: July 2020

AbstractClimate change is expected to increase the incidences of extremes in environmental conditions. To investigate how repeated disturbances affect microbial ecosystem resistance, natural lake bacterioplankton communities were subjected to repeated temperature disturbances of two intensities (25 °C and 35 °C), and subsequently to an acidification event. We measured functional parameters (bacterial production, abundance, extracellular enzyme activities) and community composition parameters (richness, evenness, niche width) and found that, compared to undisturbed control communities, the 35 °C treatment was strongly affected in all parameters, while the 25 °C treatment did not significantly differ from the control. Interestingly, exposure to multiple temperature disturbances caused gradually increasing stability in the 35 °C treatment in some parameters, while others parameters showed the opposite, indicating that the choice of parameters can strongly affect the outcome of a study. The acidification event did not lead to stronger changes in community structure, but functional resistance of bacterial production towards acidification in the 35 °C treatments increased. This indicates that functional resistance in response to a novel disturbance can be increased by previous exposure to another disturbance, suggesting similarity in stress tolerance mechanisms for both disturbances. These results highlight the need for understanding function- and disturbance-specific responses, since general responses are likely to be unpredictable.
Revealing excess protons in the infrared spectrum of liquid water
Authors: Artemov Vasily G. , Uykur Ece , Roh Seulki , Pronin Artem V. , Ouerdane Henni , Dressel Martin 
Published: July 2020

AbstractThe most common species in liquid water, next to neutral $$\hbox {H}_2\hbox {O}$$H2O molecules, are the $$\hbox {H}_3\hbox {O}^+$$H3O+ and $$\hbox {OH}^-$$OH- ions. In a dynamic picture, their exact concentrations depend on the time scale at which these are probed. Here, using a spectral-weight analysis, we experimentally resolve the fingerprints of the elusive fluctuations-born short-living $$\hbox {H}_3\hbox {O}^+$$H3O+, $$\hbox {DH}_2\hbox {O}^+$$DH2O+, $$\hbox {HD}_2\hbox {O}^+$$HD2O+, and $$\hbox {D}_3\hbox {O}^+$$D3O+ ions in the IR spectra of light ($$\hbox {H}_2\hbox {O}$$H2O), heavy ($$\hbox {D}_2\hbox {O}$$D2O), and semi-heavy (HDO) water. We find that short-living ions, with concentrations reaching $$\sim 2\%$$∼2% of the content of water molecules, coexist with long-living pH-active ions on the picosecond timescale, thus making liquid water an effective ionic liquid in femtochemistry.
Triptan efficacy does not predict onabotulinumtoxinA efficacy but improves with onabotulinumtoxinA response in chronic migraine patients
Authors: Eren Ozan E. , Gaul Charly , Peikert Andreas , Gendolla Astrid , Ruscheweyh Ruth , Straube Andreas 
Published: July 2020

AbstractChronic migraine (CM) is a highly disabling primary headache. Botulinum toxin (onabotulinumtoxinA) is effective for treatment of CM, with ~ 50% of patients responding after 24 weeks. A response predictor would prevent unnecessary treatments. Inhibiting calcitonin gene related peptide (CGRP) release from trigeminal nociceptive fibres is one of the modes of acting discussed for onabotulinumtoxinA in CM. Therefore, we hypothesized that the response to triptans might predict response to onabotulinumtoxinA. Contrariwise, onabotulinumtoxinA treatment might affect triptan efficacy. 49 CM patients scheduled for their first onabotulinumtoxinA treatment were included. Before (T0) and three months after (T1) onabotulinumtoxinA treatment, patients rated triptan efficacy and indicated number of headache days/month. At T1, patients additionally rated onabotulinumtoxinA efficacy. Headache days/month were on average reduced by 7.1 ± 7.0 days from T0 to T1 (p < 0.001). Triptan efficacy ratings at T0 did not predict onabotulinumtoxinA efficacy ratings at T1 (p = 0.19) or reduction of headache days (p = 0.37). However, triptan efficacy significantly improved from T0 to T1 in onabotulinumtoxinA responders (p < 0.001) but not in non-responders (p = 1.00). Triptan efficacy did not predict response to onabotulinumtoxinA in CM. However, triptan efficacy increased after successful onabotulinumtoxinA treatment. This supports the hypothesis that efficacy of acute migraine treatment with triptans improves with effective migraine prophylaxis.
Correlation analysis of potential factors influencing graft maturity based on MRI after lateral meniscal allograft transplantation
Authors: Ren Shiyou , Zhang Xintao , Yu Xiurong , Zhou Ri , Xu Lu , Lin Zhenglong , Zhang Wentao 
Published: July 2020

AbstractThe aim of this respective study was to assess the graft signal/noise quotient (SNQ) value and associated factors based on magnetic resonance imaging (MRI) after lateral meniscal allograft transplantation (LMAT). Patients with LMAT were included. The SNQ, width of the anterior horn (WAH), width of the midbody (WMB), width of the posterior horn (WPH) of each lateral meniscus, coronal graft extrusion (CGE), the anterior cartilage meniscus distance (ACMD) and the posterior cartilage meniscus distance (PCMD) were measured using MRI and tested by multivariate stepwise regression analysis. The relative percentage of extrusion (PRE) was calculated. Seventy-one male patients were examined, and 7 patients were lost to follow-up. The SNQ of the meniscus increased from immediately after surgery to 6 months postoperatively, decreased from 6 to 12 months, increased from 12 to 24 months, and increased from 24 to 36 months. The mean SNQ had a significant negative association with the WPH and CGE at 6 months (p < 0.05), the WPH at 1 year (p < 0.05), the PRE of CGE (CPRE) at 2 years (p < 0.05), and the PCMD, CPRE, and PRE of the PCMD (PPRE) at 3 years (p < 0.01) postoperatively. Multivariate stepwise regression analysis showed that the WPH at 6 months, WPH at 1 year, WMD and PCMD at 2 years, and WMD, ACMD and CGE at 3 years were significant independent factors correlated with the mean SNQ of grafts in different periods. Maturation of meniscal grafts fluctuated with time. The maturation process occupied the main role before 1 year postoperatively, but after the maturation process, tearing of the meniscal allograft played the leading role. Changes in an allograft’s location had an obvious association with the SNQ. The WPH influenced the graft SNQ value at 6 months and 1 year postoperatively, but after the maturation process, the WMB and graft extrusion played the same roles.
Her9/Hes4 is required for retinal photoreceptor development, maintenance, and survival
Authors: Coomer Cagney E. , Wilson Stephen G. , Titialii-Torres Kayla F. , Bills Jessica D. , Krueger Laura A. , Petersen Rebecca A. , Turnbaugh Evelyn M. , Janesch Eden L. , Morris Ann C. 
Published: July 2020

AbstractThe intrinsic and extrinsic factors that regulate vertebrate photoreceptor specification and differentiation are complex, and our understanding of all the players is far from complete. Her9, the zebrafish ortholog of human HES4, is a basic helix-loop-helix-orange transcriptional repressor that regulates neurogenesis in several developmental contexts. We have previously shown that her9 is upregulated during chronic rod photoreceptor degeneration and regeneration in adult zebrafish, but little is known about the role of her9 during retinal development. To better understand the function of Her9 in the retina, we generated zebrafish her9 CRISPR mutants. Her9 homozygous mutants displayed striking retinal phenotypes, including decreased numbers of rods and red/green cones, whereas blue and UV cones were relatively unaffected. The reduction in rods and red/green cones correlated with defects in photoreceptor subtype lineage specification. The remaining rods and double cones displayed abnormal outer segments, and elevated levels of apoptosis. In addition to the photoreceptor defects, her9 mutants also possessed a reduced proliferative ciliary marginal zone, and decreased and disorganized Müller glia. Mutation of her9 was larval lethal, with no mutants surviving past 13 days post fertilization. Our results reveal a previously undescribed role for Her9/Hes4 in photoreceptor differentiation, maintenance, and survival.
Prostate cancer-derived holoclones: a novel and effective model for evaluating cancer stemness
Authors: Flynn Louise , Barr Martin P. , Baird Anne-Marie , Smyth Paul , Casey Orla M. , Blackshields Gordon , Greene John , Pennington Stephen R. , Hams Emily , Fallon Padraic G. , O’Leary John , Sheils Orla , Finn Stephen P. 
Published: July 2020

AbstractProstate cancer accounts for approximately 13.5% of all newly diagnosed male cancer cases. Significant clinical burdens remain in terms of ineffective prognostication, with overtreatment of insignificant disease. Additionally, the pathobiology underlying disease heterogeneity remains poorly understood. As the role of cancer stem cells in the perpetuation of aggressive carcinoma is being substantiated by experimental evidence, it is crucially important to understand the molecular mechanisms, which regulate key features of cancer stem cells. We investigated two methods for in vitro cultivation of putative prostate cancer stem cells based on ‘high-salt agar’ and ‘monoclonal cultivation’. Data demonstrated ‘monoclonal cultivation’ as the superior method. We demonstrated that ‘holoclones’ expressed canonical stem markers, retained the exclusive ability to generate poorly differentiated tumours in NOD/SCID mice and possessed a unique mRNA-miRNA gene signature. miRNA:Target interactions analysis visualised potentially critical regulatory networks, which are dysregulated in prostate cancer holoclones. The characterisation of this tumorigenic population lays the groundwork for this model to be used in the identification of proteomic or small non-coding RNA therapeutic targets for the eradication of this critical cellular population. This is significant, as it provides a potential route to limit development of aggressive disease and thus improve survival rates.