bluuebunny/crossref_metadata_2025 huggingface dataset:
Argyres-Douglas theories, Painlevé II and quantum mechanics
Authors: Grassi Alba , Gu Jie
Published: February 2019

Abstract

We show in details that the all order genus expansion of the two-cut Hermitian cubic matrix model reproduces the perturbative expansion of the H
1 Argyres-Douglas theory coupled to the Ω background. In the self-dual limit we use the Painlevé/gauge correspondence and we show that, after summing over all instanton sectors, the two-cut cubic matrix model computes the tau function of Painlevé II without taking any double scaling limit or adding any external fields. We decode such solution within the context of transseries. Finally in the Nekrasov-Shatashvili limit we connect the H
1 and the H
0 Argyres-Douglas theories to the quantum mechanical models with cubic and double well potentials.
Fermion masses, mass-mixing and the almost commutative geometry of the Standard Model
Authors: Dąbrowski Ludwik , Sitarz Andrzej
Published: February 2019

Abstract

We investigate whether the Standard Model, within the accuracy of current experimental measurements, satisfies the regularity in the form of Hodge duality condition introduced and studied in [9]. We show that the neutrino and quark mass-mixing and the difference of fermion masses are necessary for this property. We demonstrate that the current data supports this new geometric feature of the Standard Model, Hodge duality, provided that all neutrinos are massive.
An anomaly-free atlas: charting the space of flavour-dependent gauged U(1) extensions of the Standard Model
Authors: Allanach B. C. , Davighi Joe , Melville Scott
Published: February 2019

Abstract

Spontaneously broken, flavour-dependent, gauged U(1) extensions of the Standard Model (SM) have many phenomenological uses. We chart the space of solutions to the gauge anomaly cancellation equations in such extensions, for both the SM chiral fermion content and the SM plus (up to) three right-handed neutrinos (SMν

R
). Methods from Diophantine analysis allow us to efficiently index the solutions arithmetically, and produce the complete solution space in particular cases. In order to solve the general case, we build a computer program which cycles through possible U(1) charge assignments, providing all solutions for charges up to some pre-defined maximum absolute charge. Lists of anomaly-free U(1) charge assignments result, which corroborate the results of our Diophantine analysis. We make these lists, which may be queried for further desirable properties, publicly available. This previously uncharted space of anomaly-free charge assignments has been little explored until now, paving the way for future model building and phenomenological studies.
Comparison of Anterior Chamber Depth between Normal and Keratoconic Eyes
Authors: Hashemi Hassan , Yekta AbbasAli , Yazdani Negareh , Ostadimoghaddam Hadi , Khabazkhoob Mehdi
Published: February 2019

Purpose:

To review the published data about changes in the anterior chamber depth (ACD) in keratoconus patients.

Methods:

In this systematic review and meta-analysis of observational studies, we reviewed the available and relevant literature on anterior segment changes in keratoconic eyes, with a special focus on the ACD, an effective factor in many surgical methods. Articles published up to December 2017 were identified in the following data sources: PubMed, Scopus, Ovid, ISI, ScienceDirect, and Google Scholar. Databases were comprehensively searched using the key words “Anterior Chamber Depth AND Anterior segment AND Keratoconus”.

Results:

A total of 496 studies including these key words were detected. Four hundred fifty-three studies were excluded, and overall 16 studies which precisely described the change in ACD were included in the literature review. The results show that with respect to the applied device, there was a statistically significant difference in ACD between keratoconic eyes and normal eyes except for Galilei analyzer.

Conclusion:

Summarizing the results of studies, this review revealed that ACD is significantly deeper in keratoconic eyes as compared with normal eyes, which could be explained by the steeper corneal curvature.
The Woman’s Body (Not the Man’s One) Is Used to Evaluate Sexual Desire: An Eye-Tracking Study of Automatic Visual Attention
Authors: Bolmont Mylene , Bianchi-Demicheli Francesco , Boisgontier Matthieu P. , Cheval Boris
Published: February 2019

Introduction

Vision of the human body has been shown to be key in eliciting sexual desire. However, whether the visual pattern characterizing sexual desire is different in women and men is still unclear.

Aim

To investigate the effect of gender on visual patterns triggered by an identical set of stimuli depicting attractive heterosexual couples.

Methods

Heterosexual women and men (n = 106) were tested on a picture-viewing task associated with eye tracking. The context of sexual desire was activated by asking the participant whether they perceived such desire while looking at sensual pictures of heterosexual couples. Data were analyzed using mixed-subject design analyses of variance.

Main Outcome Measure

Fixation durations were used to investigate visual patterns. 2 areas of interest were created to investigate visual patterns (face vs body area).

Results

Results showed longer fixations on body rather than face areas irrespective of participant gender. Moreover, all participants looked longer at women’s than men’s bodies and at the faces of the opposite sex.

Clinical Implications

These findings shed light on the automatic processes underlying sexual desire, which has the potential to improve the care of patients suffering from sexual disorders by optimizing interventions.

Strengths & Limitations

The strengths of this study are the use of an eye-tracking paradigm, the dissociation between 2 fixation areas (ie, face and body), and the use of an identical set of stimuli allowing an accurate between-gender comparison of the visual pattern. The limitations are the small sample size, the use of healthy heterosexual individuals, and the absence of measures of sexual arousal and genital response.

Conclusions

These findings confirm the association between the human body and sexual desire. They also reveal the unique attentional attractiveness of woman’s bodies across genders.
Adopting robot lawyer? The extending artificial intelligence robot lawyer technology acceptance model for legal industry by an exploratory study
Authors: Xu Ni , Wang Kung-Jeng
Published: February 2019

The development of artificial intelligence has created new opportunities and challenges in industries. The competition between robots and humans has elicited extensive attention among legal researchers. In this exploratory study, we addressed issues regarding the introduction of robots to the practice of legal service through a semistructured interviews with lawyers, judges, artificial intelligence experts, and potential clients. An extended robot lawyer technology acceptance model with five facets and 11 elements is proposed in this study. This model highlights two dimensions: ‘legal use’ and ‘perception of trust.’ In summary, this study provides new specific implications and exhibits three characteristics, namely, derivative, macroscopic, and instructive, in the legal services with artificial intelligence. In addition, artificial intelligence robot lawyers are being developed with some of the abilities necessary to substitute for human beings. Nevertheless, working with human lawyers is imperative to produce benefits from this type of reciprocity.
No significant mass loss in the glaciers of Astore Basin (North-Western Himalaya), between 1999 and 2016
Authors: MUHAMMAD SHER , TIAN LIDE , NÜSSER MARCUS
Published: February 2019

Although glaciers in High Mountain Asia produce an enormous amount of water used by downstream populations, they remain poorly observed in the field. This study presents a geodetic mass balance of the glaciers in the Astore Basin (with differential GPS (dGPS) measurements on Harcho glacier) between 1999 and 2016. Changes near the terminus of Harcho glacier (below 3800 m a.s.l.) featured heterogeneous surface elevation changes, whereas the middle section shows the most negative changes. The surface elevation changes were positive above 4200 m a.s.l. The average annual mass balance was −0.08 ± 0.07 m w.e. a−1 derived from a dGPS and DEM comparison whereas Advanced Spaceborne Thermal Emission and Reflection Radiometer DEM-based results show a slightly positive, that is 0.03 ± 0.24 m w.e. a−1 in the same period. In contrast, the terminus indicates a substantial retreat of ~368 m (4.5 m a−1) between 1934 and 2016. The average mass balance of 19 glaciers (>2 km2) covering ~60% of the total glaciers in the Basin exhibit no net mass loss in the period of 2000−2016 and follow a pattern similar to adjacent Karakoram glaciers.
Cagliari Sardinian
Authors: Mereu Daniela
Published: February 2019

Sardinian is a Romance language spoken almost exclusively on the island of Sardinia, an autonomous region of Italy. Sardinian and Italian are not mutually intelligible; there is considerable structural distance between the two linguistic systems, at all linguistic levels (Loporcaro 2009: 162–171).
Kenoticism and essential divine properties
Authors: YANG ERIC
Published: February 2019

Traditional Christology maintains that Christ was a single divine person with two natures (human and divine). According to kenotic Christology, certain divine properties such as omniscience and omnipotence were divested in order for Christ to acquire essential human properties. However, such a view appears to conflict with perfect-being theology, which takes omniscience and omnipotence to be essential properties for being divine. I propose a view that adopts a Thomistic theory of essences in order to show that there need be no conflict, and hence Christ can give up the property of being omniscient while still being essentially omniscient.
Reading bedtime stories to compatriots: Reconciling global equality of opportunity and self-determination
Authors: Banai Ayelet , Kollar Eszter
Published: February 2019

In this article, we propose a reconciliation between global equality of opportunity and self-determination, two central and seemingly conflicting principles in the contemporary theory of global justice. Our conception of reconciliation draws on the family-people analogy, following the account of familial relationship goods, developed by Harry Brighouse and Adam Swift, on permissible parental partiality and domestic equality of opportunity. We argue, first, that a plausible conception of global equality of opportunity must be able to distinguish morally arbitrary aspects of nationality that require mitigation from morally permissible ones. Second, we argue that a plausible criterion for the distinction integrates a person’s normative interests over a lifetime: (i) the interests of a child born into societal circumstances that impact her life prospects; and (ii) the interests of an adult citizen in collective self-determination. Third, we outline an account of ‘people relationship goods’, as a principled way to circumscribe the permissible scope of self-determination. Fair global equality of opportunity requires mitigating nationality-tracking inequalities, except those that fall within the permissible scope of collective self-determination.
The reproduction of child maltreatment: An examination of adolescent problem behavior, substance use, and precocious transitions in the link between victimization and perpetration
Authors: Augustyn Megan Bears , Thornberry Terence P. , Henry Kimberly L.
Published: February 2019

Growing evidence suggests that maltreatment is reproduced across generations as victims of maltreatment are at an increased risk for maltreatment perpetration. Unfortunately, little information about mediating pathways exists to provide an explanation for why maltreatment begets maltreatment. We use the number of types of maltreatment experienced to predict later maltreatment perpetration and then examine two developmental pathways that may serve as bridges between maltreatment victimization and perpetration: adolescent problem behaviors and precocious transitions to adulthood. With prospective, longitudinal data from the Rochester Youth Development Study, we assess the relevance of these pathways for the number of maltreatment experiences as well as the number of maltreatment victimization experiences by developmental period (i.e., childhood and adolescence). Our results demonstrate a significant relationship between maltreatment victimization and maltreatment perpetration. Adolescent delinquency and two precocious transitions, dropping out of school and independent living, as well as the accumulation of precocious transitions and problem behaviors, serve as mediators of this intergenerational relationship. Furthermore, the relationship between the number of types of maltreatment and subsequent perpetration is primarily driven by experiences of maltreatment during adolescence. We discuss the implications of these results and set an agenda for the development of programs and policies to interrupt the cycle of maltreatment.
Reliability and validity of body weight and body image perception in children and adolescents from the South American Youth/Child Cardiovascular and Environmental (SAYCARE) Study
Authors: González-Zapata Laura I , Restrepo-Mesa Sandra L , Aristizabal Juan C , Skapino Estela , Collese Tatiana S , Azzaretti Leticia B , Nascimento-Junior Walter V , Moreno Luis A , De Moraes Augusto César F , Carvalho Heráclito B , Estrada-Restrepo Alejandro
Published: February 2019

Objective

To assess the reliability and validity of body weight (BW) and body image (BI) perception reported by parents (in children) and by adolescents in a South American population.

Design

Cross-sectional study. BW perception was evaluated by the question, ‘Do you think you/your child are/is: severely wasted, wasted, normal weight, overweight, obese?’ BI perception was evaluated using the Gardner scale. To evaluate reliability, BW and BI perceptions were reported twice, two weeks apart. To evaluate validity, the BW and BI perceptions were compared with WHO BMI Z-scores. Kappa and Kendall’s tau-c coefficients were obtained.

Setting

Public and private schools and high schools from six countries of South America (Argentina, Peru, Colombia, Uruguay, Chile, Brazil).

Participants

Children aged 3–10 years (n 635) and adolescents aged 11–17 years (n 400).

Results

Reliability of BW perception was fair in children’s parents (κ=0·337) and substantial in adolescents (κ=0·709). Validity of BW perception was slight in children’s parents (κ=0·176) and fair in adolescents (κ=0·268). When evaluating BI, most children were perceived by parents as having lower weight. Reliability of BI perception was slight in children’s parents (κ=0·124) and moderate in adolescents (κ=0·599). Validity of BI perception was poor in children’s parents (κ=−0·018) and slight in adolescents (κ=0·023).

Conclusions

Reliability of BW and BI perceptions was higher in adolescents than in children’s parents. Validity of BW perception was good among the parents of the children and adolescents with underweight and normal weight.
A Gas-Phase Reaction Cell for Modern Atom Probe Systems
Authors: Haley Daniel , McCarroll Ingrid , Bagot Paul A. J. , Cairney Julie M. , Moody Michael P.
Published: February 2019

In this work, we demonstrate a new system for the examination of gas interactions with surfaces via atom probe tomography. This system provides capability of examining the surface and subsurface interactions of gases with a wide range of specimens, as well as a selection of input gas types. This system has been primarily developed to aid the investigation of hydrogen interactions with metallurgical samples, to better understand the phenomenon of hydrogen embrittlement. In its current form, it is able to operate at pressures from 10−6to 1000 mbar (abs), can use a variety of gasses, and is equipped with heating and cryogenic quenching capabilities. We use this system to examine the interaction of hydrogen with Pd, as well as the interaction of water vapor and oxygen in Mg samples.
Statistically Rigorous Silver Nanowire Diameter Distribution Quantification by Automated Electron Microscopy and Image Analysis
Authors: Todd Clifford S. , Heeschen William A. , Eastman Peter Y. , Keene Ellen C.
Published: February 2019

Silver nanowire (AgNW) diameters are typically characterized by manual measurement from high magnification electron microscope images. Measurement is monotonous and has potential ergonomic hazards. Because of this, statistics regarding wire diameter distribution can be poor, costly, and low-throughput. In addition, manual measurements are of unknown uncertainty and operator bias. In this paper we report an improved microscopy method for diameter and yield measurement of nanowires in terms of speed/automation and reduction of analyst variability. Each step in the process to generate these measurements was analyzed and optimized: microscope imaging conditions, sample preparation for imaging, image acquisition, image analysis, and data processing. With the resulting method, average diameter differences between samples of just a few nanometers can be confidently and statistically distinguished, allowing the identification of subtle incremental improvements in reactor processing conditions, and insight into nucleation and growth kinetics of AgNWs.
HIGHER ORDER DIFFERENTIABILITY OF OPERATOR FUNCTIONS IN SCHATTEN NORMS
Authors: Le Merdy Christian , Skripka Anna
Published: February 2019

We establish the following results on higher order ${\mathcal{S}}^{p}$-differentiability, $1<p<\infty$, of the operator function arising from a continuous scalar function $f$ and self-adjoint operators defined on a fixed separable Hilbert space:

(i)

$f$ is $n$ times continuously Fréchet ${\mathcal{S}}^{p}$-differentiable at every bounded self-adjoint operator if and only if $f\in C^{n}(\mathbb{R})$;

(ii)

if $f^{\prime },\ldots ,f^{(n-1)}\in C_{b}(\mathbb{R})$ and $f^{(n)}\in C_{0}(\mathbb{R})$, then $f$ is $n$ times continuously Fréchet ${\mathcal{S}}^{p}$-differentiable at every self-adjoint operator;

(iii)

if $f^{\prime },\ldots ,f^{(n)}\in C_{b}(\mathbb{R})$, then $f$ is $n-1$ times continuously Fréchet ${\mathcal{S}}^{p}$-differentiable and $n$ times Gâteaux ${\mathcal{S}}^{p}$-differentiable at every self-adjoint operator.

We also prove that if $f\in B_{\infty 1}^{n}(\mathbb{R})\cap B_{\infty 1}^{1}(\mathbb{R})$, then $f$ is $n$ times continuously Fréchet ${\mathcal{S}}^{q}$-differentiable, $1\leqslant q<\infty$, at every self-adjoint operator. These results generalize and extend analogous results of Kissin et al. (Proc. Lond. Math. Soc. (3)108(3) (2014), 327–349) to arbitrary $n$ and unbounded operators as well as substantially extend the results of Azamov et al. (Canad. J. Math.61(2) (2009), 241–263); Coine et al. (J. Funct. Anal.; doi:10.1016/j.jfa.2018.09.005); Peller (J. Funct. Anal.233(2) (2006), 515–544) on higher order ${\mathcal{S}}^{p}$-differentiability of $f$ in a certain Wiener class, Gâteaux ${\mathcal{S}}^{2}$-differentiability of $f\in C^{n}(\mathbb{R})$ with $f^{\prime },\ldots ,f^{(n)}\in C_{b}(\mathbb{R})$, and Gâteaux ${\mathcal{S}}^{q}$-differentiability of $f$ in the intersection of the Besov classes $B_{\infty 1}^{n}(\mathbb{R})\cap B_{\infty 1}^{1}(\mathbb{R})$. As an application, we extend ${\mathcal{S}}^{p}$-estimates for operator Taylor remainders to a broad set of symbols. Finally, we establish explicit formulas for Fréchet differentials and Gâteaux derivatives.
Beyond Democracy-Dictatorship Measures: A New Framework Capturing Executive Bases of Power, 1789–2016
Authors: Teorell Jan , Lindberg Staffan I.
Published: February 2019

We attempt to integrate the literatures on authoritarian regime types and democratic forms of government. We propose a theoretical framework of five dimensions of executive appointment and dismissal that can be applied in both more democratic and more authoritarian regimes: the hereditary, military, ruling party, direct election, and confidence dimensions, respectively. Relying on the Varieties of Democracy data, we provide measures of these five dimensions for 3,937 individual heads of state and 2,874 heads of government from 192 countries across the globe from 1789 to the present. After presenting descriptive evidence of their prevalence, variation, and relationship to extant regime typologies, a set of exploratory probes gauge the extent to which the five dimensions can predict levels of repression, corruption, and executive survival, controlling for aspects of democracy. This leads to generation of a set of original hypotheses that we hope can serve as building blocks for explanatory theory. We conclude by discussing some limitations of these novel data.
From Within to Between Nations: Subnational Comparison across Borders
Authors: Sellers Jefferey M.
Published: February 2019

Long a staple in the toolkit of American politics, comparison among subnational territorial units has gained increasing currency in comparative politics. A growing portion of subnational research, especially in the monographic literature, employs comparisons of subnational territorial units within different countries. This approach to comparison, which I term transnational comparison, has the potential to build on and extend the advantages of subnational comparison. Despite the numerous added challenges it poses, transnational comparison offers a variety of ways to incorporate and leverage variations between countries as well as within them. Drawing on exemplary studies from the literature on subnational regimes and beyond, I outline a typology of successful transnational comparative strategies. The choice among these strategies depends on their distinctive properties, on the substantive questions asked, and on the stage of a research program. All have contributed to advancing the study of politics beyond nation-centered comparison.
A Dialogue with the Data: The Bayesian Foundations of Iterative Research in Qualitative Social Science
Authors: Fairfield Tasha , Charman Andrew
Published: February 2019

We advance efforts to explicate and improve inference in qualitative research that iterates between theory development, data collection, and data analysis, rather than proceeding linearly from hypothesizing to testing. We draw on the school of Bayesian “probability as extended logic,” where probabilities represent rational degrees of belief in propositions given limited information, to provide a solid foundation for iterative research that has been lacking in the qualitative methods literature. We argue that mechanisms for distinguishing exploratory from confirmatory stages of analysis that have been suggested in the context of APSA’s DA-RT transparency initiative are unnecessary for qualitative research that is guided by logical Bayesianism, because new evidence has no special status relative to old evidence for testing hypotheses within this inferential framework. Bayesian probability not only fits naturally with how we intuitively move back and forth between theory and data, but also provides a framework for rational reasoning that mitigates confirmation bias and ad-hoc hypothesizing—two common problems associated with iterative research. Moreover, logical Bayesianism facilitates scrutiny of findings by the academic community for signs of sloppy or motivated reasoning. We illustrate these points with an application to recent research on state building.
“Petit Spot” Rejuvenated Volcanism Superimposed on Plume‐Derived Samoan Shield Volcanoes: Evidence From a 645‐m Drill Core From Tutuila Island, American Samoa
Authors: Reinhard Andrew A. , Jackson Matthew G. , Blusztajn Jerzy , Koppers Anthony A. P. , Simms Alexander R. , Konter Jasper G.
Published: February 2019

In 2015 a geothermal exploration well was drilled on the island of Tutuila, American Samoa. The sample suite from the drill core provides 645 m of volcanic stratigraphy from a Samoan volcano, spanning 1.45 million years of volcanic history. In the Tutuila drill core, shield lavas with an EM2 (enriched mantle 2) signature are observed at depth, spanning 1.46 to 1.44 Ma. These are overlain by younger (1.35 to 1.17 Ma) shield lavas with a primordial “common” (focus zone) component interlayered with lavas that sample a depleted mantle component. Following ~1.15 Myr of volcanic quiescence, rejuvenated volcanism initiated at 24.3 ka and samples an EM1 (enriched mantle 1) component. The timing of the initiation of rejuvenated volcanism on Tutuila suggests that rejuvenated volcanism may be tectonically driven, as Samoan hotspot volcanoes approach the northern terminus of the Tonga Trench. This is consistent with a model where the timing of rejuvenated volcanism at Tutuila and at other Samoan volcanoes relates to their distance from the Tonga Trench. Notably, the Samoan rejuvenated lavas have EM1 isotopic compositions distinct from shield lavas that are geochemically similar to “petit spot” lavas erupted outboard of the Japan Trench and late stage lavas erupted at Christmas Island located outboard of the Sunda Trench. Therefore, like the Samoan rejuvenated lavas, petit spot volcanism in general appears to be related to tectonic uplift outboard of subduction zones, and existing geochemical data suggest that petit spots share similar EM1 isotopic signatures.
Deep Argo Quantifies Bottom Water Warming Rates in the Southwest Pacific Basin
Authors: Johnson Gregory C. , Purkey Sarah G. , Zilberman Nathalie V. , Roemmich Dean
Published: February 2019

Data reported from mid‐2014 to late 2018 by a regional pilot array of Deep Argo floats in the Southwest Pacific Basin are used to estimate regional temperature anomalies from a long‐term climatology as well as regional trends over the 4.4 years of float data as a function of pressure. The data show warm anomalies that increase with increasing pressure from effectively 0 near 2,000 dbar to over 10 (±1) m°C by 4,800 dbar, uncertainties estimated at 5–95%. The 4.4‐year trend estimate shows warming at an average rate of 3 (±1) m°C/year from 5,000 to 5,600 dbar, in the near‐homogeneous layer of cold, dense bottom water of Antarctic origin. These results suggest acceleration of previously reported long‐term warming trends in the abyssal waters in this region. They also demonstrate the ability of Deep Argo to quantify changes in the deep ocean in near real‐time over short periods with high accuracy.
Melting of CaSiO3 Perovskite at High Pressure
Authors: Braithwaite James , Stixrude Lars
Published: February 2019

Ab initio molecular dynamics simulations predict that CaSiO3 perovskite melts at 5600 K at 136 GPa, and 6400 K at 300 GPa, significantly higher than MgSiO3 perovskite. The entropy of melting (1.8 kB per atom) is much larger than that of many silicates at ambient pressure and of simple liquids and varies little with pressure. The volume of melting decreases rapidly with increasing pressure, to 3 % at 136 GPa, producing a melting slope that diminishes rapidly with pressure. We determine the melting temperature via the ZW method, combining the Z method, for which we clarify the theoretical basis, with a waiting time analysis. The ZW method results are internally confirmed by integrating the Clausius‐Clapeyron equation, which also yields our results for the entropy and volume of melting. We find the eutectic composition on the MgSiO3‐CaSiO3 join to be xCa = 0.26 at 136 GPa and that metasilicate melt is denser than coexisting silicates.
On the Accuracy of Adiabaticity Parameter Estimations Using Magnetospheric Models
Authors: Haiducek John D. , Ganushkina Natalia Y. , Dubyagin Stepan , Welling Daniel T.
Published: February 2019

Recent studies have found that even during quiet times, observed proton isotropic boundaries (IBs) are often projected to the region of high adiabaticity parameter (K≈30), where
is the ratio of magnetic field line radius of curvature to the particle gyroradius. This contradicts the accepted hypothesis that current sheet scattering (CSS) is the dominant mechanism of IB formation because K≈8 would be expected for this mechanism. We used magnetohydrodynamic simulations and empirical models to compute K for 30‐keV proton IB observations within 3 hr of local midnight. We found that neither class of model reliably estimates K unless supported by magnetic field observations in the current sheet. magnetohydrodynamic simulations produced higher K values than expected for CSS (K = 15–30), and empirical models gave lower values (K < 4). We obtained reliable estimates of K by controlling for the accuracy of the normal component and the gradient of the radial component in the neutral sheet, using observations from three Time History of Events and Macroscale Interactions during Substorms satellites. For the first time, we demonstrated that both these variables should be taken into account for the accurate estimation of the curvature radius. This greatly reduced the spread of K values, indicating that much of the previous spread was due to errors in the magnetic field but also that these errors can be controlled. Most of the corrected values fall within the expected range for CSS, supporting the hypothesis that the IB's were formed by CSS. Accounting for all model results, we obtain an average corrected value of K = 6.0.
Thermoelasticity of Iron‐ and Aluminum‐Bearing MgSiO3 Postperovskite
Authors: Shukla Gaurav , Sarkar Kanchan , Wentzcovitch Renata M.
Published: February 2019

We present ab initio (LDA + Usc) studies of high‐temperature and high‐pressure elastic properties of pure as well as iron‐bearing (ferrous, Fe2+, and ferric, Fe3+) and aluminum‐bearing MgSiO3 postperovskite, the likely dominant phase in the deep lower mantle of the Earth. Thermal effects are addressed within the quasiharmonic approximation by combining vibrational density of states and static elastic coefficients. Aggregate elastic moduli and sound velocities for the Mg end members are successfully compared with scarce experimental data available. Effects of iron (Fe) and aluminum (Al) substitutions on elastic properties and their pressure and temperature dependence have been thoroughly investigated. At the observed perovskite to postperovskite transition (P = 125 GPa and T = 2,500 K), compressional and shear velocities increase by 0–1% and 1.5–3.75%, respectively. This observation is consistent with some seismic studies of the D′′ discontinuity beneath the Caribbean, which suggests that our robust estimates of elastic properties of the postperovskite phase will be very helpful to understand lateral velocity variations in the deep lower mantle region and to constrain its composition and thermal structure.
Factors Affecting the Spatial and Temporal Variations in Soil Erodibility of China
Authors: Zhu Guangyu , Tang Zhuangsheng , Shangguan Zhouping , Peng Changhui , Deng Lei
Published: February 2019

Soil erosion occurs extensively across China, leading to severe degradation of the land and ecosystem services. However, the spatial and temporal variations in soil erodibility (k) and the distribution of soil erosion across land use types and slopes remain unclear. We synthesized the results from 325 sites published in 152 literatures to analyze the factors affecting the k, such as land use type, climate, topography, soil, and vegetation restoration age. The results showed that areas with slopes >25° had a larger k factor (k = 0.1047) than did those with slope <6° (k = 0.0637) or 6–25° (k = 0.0832). The k from 2006 to 2011 (k = 0.0725) was higher than that from 1999 to 2005 (k = 0.058) and that from 2012 to 2016 (k = 0.0631). The k value initially increased with vegetation restoration age and then gradually decreased. Land use also had an impact on the k factor, with the k factor of cropland (k = 0.0697) being higher than that of grassland (k = 0.0663) but lower than that of forest (k = 0.0967). Across China, North Shaanxi, Heilongjiang, and South Guizhou, which are located in the Loess Plateau in Northwest China, the Black Soil region of Northeast China, and the Karst areas in Southwest China, respectively, were the three most severely eroded regions due to hydraulic erosion, frost‐thaw erosion, and high‐intensity erosion, respectively. Overall, the most important factors affecting the k were soil characteristics, followed by topography and climate. Among them, soil nitrogen and precipitation were the two most critical factors influencing the k.
Forensic Probe of Bali’s Great Volcano
Authors: Deegan Frances , Troll Valentin , Geiger Harri
Published: February 2019

Evidence from volcanic crystals sheds light on magma storage under Mount Agung and helps explain this giant volcano’s frequent eruptions.
Unravelling the Past Using Elements and Isotopes
Authors: Sial Alcides , Ferreira Valderez , Gaucher Claudio , Ramkumar Muthuvairavasamy
Published: February 2019

A new book explores chemostratigraphy, a fascinating and relatively young branch of geoscience, presenting the latest developments and applications.
Targeting autophagy potentiates antitumor activity of Met-TKIs against Met-amplified gastric cancer
Authors: Lin Xiaoting , Peng Zhi , Wang Xiaojuan , Zou Jianling , Chen Dongshao , Chen Zuhua , Li Zhongwu , Dong Bin , Gao Jing , Shen Lin
Published: February 2019

Met tyrosine kinase inhibitors (Met-TKIs) subjected to ongoing clinical trials are a promising option for Met-amplified gastric cancer (GC), but how to optimize their antitumor activity especially with combination schemes remains unclear. Since autophagy is known to be initiated by Met-TKIs, we investigated its underlying mechanisms and therapeutic potentials of Met-TKIs combined with autophagy inhibitors against Met-amplified GC. As expected, four Met-TKIs induced autophagy in Met-amplified GC cells marked by p62 degradation, LC3-II accumulation and increased LC3-positive puncta. Autophagy flux activation by Met-TKIs was further validated with combined lysosomal inhibitors, bafilomycin A1 (Baf A1) and hydroxychloroquine (HCQ). Molecular investigations reveal that autophagy induction along with mTOR and ULK1 de-phosphorylation upon Met-TKI treatment could be relieved by hepatocyte growth factor (HGF) and mTOR agonist MHY1485 (MHY), suggesting that autophagy was initiated by Met-TKIs via Met/mTOR/ULK1 cascade. Intriguingly, Met-TKIs further suppressed cell survival and tumor growth in the presence of autophagy blockade in Met-amplified GC preclinical models. Thus, these findings indicate Met/mTOR/ULK1 cascade responsible for Met-TKI-mediated autophagy and Met-TKIs combined with autophagy inhibitors as a promising choice to treat Met-amplified GC.
Baicalin ameliorates lupus autoimmunity by inhibiting differentiation of Tfh cells and inducing expansion of Tfr cells
Authors: Yang Ji , Yang Xue , Yang Jie , Li Ming
Published: February 2019

Baicalin is a natural compound isolated from Chinese herb, which has been reported as an anti-inflammatory drug. Here, we demonstrated that Baicalin treatment could reduce urine protein, inhibit anti-ds-DNA antibody titers, and ameliorate lupus nephritis in MRL/lpr lupus-prone mice. Baicalin inhibited Tfh cell differentiation and IL-21 production, but promoted Foxp3+ regulatory T cell differentiation including part of follicular regulatory T (Tfr) cells. Intravenous injection of Baicalin-induced Foxp3+ regulatory T cells could relieve nephritis, inhibit Tfh cell differentiation and IL-21 production. Baicalin inhibited mTOR activation, reduced mTOR agonist-mediated Tfh cell expansion and increased Tfr cells. These data suggest that Baicalin attenuates lupus autoimmunity by up- and downregulating the differentiation of Tfr cells and Tfh cells, respectively. Baicalin and ex vivo expanded Foxp3+ regulatory T cells are promising therapeutics for the treatment of lupus.
Astrocytic miR-324-5p is essential for synaptic formation by suppressing the secretion of CCL5 from astrocytes
Authors: Sun Chenxi , Zhu Liang , Ma Rongjie , Ren Jie , Wang Jian , Gao Shane , Yang Danjing , Ning Ke , Ling Bin , Lu Bing , Chen Xu , Xu Jun
Published: February 2019

There is accumulating evidence that astrocytes play an important role in synaptic formation, plasticity, and pruning. Dicer and the fine-tuning of microRNA (miRNA) network are important for maintaining the normal functions of central nervous system and dysregulation of miRNAs is implicated in neurological disorders. However, little is known about the role of Dicer and miRNAs of astrocytes in the homeostasis of synapse as well as its plasticity. By selectively deleting Dicer in postnatal astrocytes, Dicer-deficient mice exhibited reactive astrogliosis and deficits in dendritic spine formation. Astrocyte-conditioned medium (ACM) collected from Dicer-null astrocytes caused synapse degeneration in cultured primary neurons. The expression of chemokine ligand 5 (CCL5) elevated in Dicer-deleted astrocytes which led to the significant augmentation of secreted CCL5 in ACM. In neurons treated with Dicer KO-ACM, CCL5 supplementation inhibited MAPK/CREB signaling pathway and exacerbated the synaptic formation deficiency, while CCL5 knockdown partially rescued the synapse degeneration. Moreover, we validated CCL5 as miR-324-5p targeted gene. ACM collected from miR-324-5p antagomir-transfected astrocytes mimicked the effect of CCL5 treatment on inhibiting synapse formation and MAPK/CREB signaling in Dicer KO-ACM-cocultured neurons. Furthermore, decreased miR-324-5p expression and elevated CCL5 expression were observed in the brain of aging mice. Our work reveals the non-cell-autonomous roles of astroglial miRNAs in regulation of astrocytic secretory milieu and neuronal synaptogenesis, implicating the loss or misregulation of astroglial miRNA network may contribute to neuroinflammation, neurodegeneration, and aging.
Fisetin induces autophagy in pancreatic cancer cells via endoplasmic reticulum stress- and mitochondrial stress-dependent pathways
Authors: Jia Shengnan , Xu Xiaodong , Zhou Senhao , Chen Yan , Ding Guoping , Cao Liping
Published: February 2019

Pancreatic cancer is one of the most aggressive tumors and patients have poor survival rates. Fisetin, a natural flavonoid, was recently reported to have antitumor effects in various cancer models. Autophagy is a conserved catabolic process that maintains cellular homoeostasis in response to stress, and together with apoptosis, determines cell fate. Herein, we examined the effect of fisetin on pancreatic cancer. We reveal that fisetin inhibits PANC-1 cell proliferation using a real-time cell analysis system. Moreover, the in vivo antitumor effect of fisetin was verified in pancreatic cancer using a luciferase-expressing murine xenograft pancreatic cancer model. We found that the AMPK/mTOR signaling pathway was enhanced after fisetin treatment; however, autophagy was not diminished by adding the AMPK inhibitor compound C. Thus, we hypothesized that an another autophagy regulating pathway existed. RNA-seq analysis revealed that the unfolded protein response pathway, which is activated by ER stress, was enriched. We also found that the stress-induced transcription factor p8 was increased in fisetin-treated PANC-1 cells, and that fisetin-induced autophagy was blocked by silencing p8. We revealed that p8-dependent autophagy was AMPK-independent, and that p8 regulated ATF6, ATF4, and PERK in response to ER stress via p53/PKC-α-mediated signaling. Furthermore, mitophagy was associated with Parkin and PINK1 in response to mitochondrial stress. Interestingly, ATF4 and ATF6 were increased in cells treated with fisetin and compound C. Moreover, inhibiting the AMPK/mTOR pathway with compound C may upregulate p8-dependent autophagy. Thus, there may be crosstalk between the AMPK/mTOR and p8-dependent pathways.
Visible-light photocatalysis by carbon-nano-onion-functionalized ZnO tetrapods: degradation of 2,4-dinitrophenol and a plant-model-based ecological assessment
Authors: Park Seung Jun , Das Gouri Sankar , Schütt Fabian , Adelung Rainer , Mishra Yogendra Kumar , Tripathi Kumud Malika , Kim TaeYoung
Published: February 2019

The visible-light-induced photocatalytic performance of a three-dimensional (3D) hybrid composite based on carbon nano-onion (CNO)-functionalized zinc-oxide tetrapods (T-ZnO) was investigated to study the photocatalytic degradation of 2,4-dinitrophenol (DNP). The hybrid CNO-functionalized T-ZnO 3D composite was successfully developed via a facile one-step process. The CNOs, synthesized via a green route from flaxseed oil, were decorated on the surface of T-ZnO via chemical mixing. Such a hybrid composite allows for the complete optimization of the T-ZnO/CNO interface to enhance visible-light harvesting, contributing to effective visible-light-induced photocatalysis. The enhanced photocatalytic performance of the T-ZnO-CNO 3D composite is attributed to the strong synergistic effects obtained by the unique cumulative intrinsic properties of CNOs and the 3D architecture of T-ZnO, which lead to exceptional charge transfer and separation. A reaction mechanism for the degradation of DNP is proposed based on a bandgap analysis and trapping experiments. Furthermore, the photocatalyst maintains a favorable reusability during consecutive cycling experiments. The ecological assessment of the photocatalytic process was performed via the germination of common gram seeds (Cicer arietinum) and reveals the low toxicity and environmental safety of the synthesized hybrid 3D composite. The observations confirm that the synthesized hybrid 3D composite facilitates wastewater decontamination using photocatalytic technology and highlights the broad implications of designing multifunctional materials for various advanced applications.
Direct measurements of ice-shelf flexure caused by surface meltwater ponding and drainage
Authors: Banwell Alison F. , Willis Ian C. , Macdonald Grant J. , Goodsell Becky , MacAyeal Douglas R.
Published: February 2019

Global sea-level rise is caused, in part, by more rapid ice discharge from Antarctica, following the removal of the restraining forces of floating ice-shelves after their break-up. A trigger of ice-shelf break-up is thought to be stress variations associated with surface meltwater ponding and drainage, causing flexure and fracture. But until now, there have been no direct measurements of these processes. Here, we present field data from the McMurdo Ice Shelf, Antarctica, showing that the filling, to ~2 m depth, and subsequent draining, by overflow and channel incision, of four surface lakes causes pronounced and immediate ice-shelf flexure over multiple-week timescales. The magnitude of the vertical ice-shelf deflection reaches maxima of ~1 m at the lake centres, declining to zero at distances of <500 m. Our results should be used to guide development of continent-wide ice-sheet models, which currently do not simulate ice-shelf break-up due to meltwater loading and unloading.
Calcium signals are necessary to establish auxin transporter polarity in a plant stem cell niche
Authors: Li Ting , Yan An , Bhatia Neha , Altinok Alphan , Afik Eldad , Durand-Smet Pauline , Tarr Paul T. , Schroeder Julian I. , Heisler Marcus G. , Meyerowitz Elliot M.
Published: February 2019

In plants mechanical signals pattern morphogenesis through the polar transport of the hormone auxin and through regulation of interphase microtubule (MT) orientation. To date, the mechanisms by which such signals induce changes in cell polarity remain unknown. Through a combination of time-lapse imaging, and chemical and mechanical perturbations, we show that mechanical stimulation of the SAM causes transient changes in cytoplasmic calcium ion concentration (Ca2+) and that transient Ca2+ response is required for downstream changes in PIN-FORMED 1 (PIN1) polarity. We also find that dynamic changes in Ca2+ occur during development of the SAM and this Ca2+ response is required for changes in PIN1 polarity, though not sufficient. In contrast, we find that Ca2+ is not necessary for the response of MTs to mechanical perturbations revealing that Ca2+ specifically acts downstream of mechanics to regulate PIN1 polarity response.
tmem33 is essential for VEGF-mediated endothelial calcium oscillations and angiogenesis
Authors: Savage Aaron M. , Kurusamy Sathishkumar , Chen Yan , Jiang Zhen , Chhabria Karishma , MacDonald Ryan B. , Kim Hyejeong R. , Wilson Heather L. , van Eeden Fredericus J. M. , Armesilla Angel L. , Chico Timothy J. A. , Wilkinson Robert N.
Published: February 2019

Angiogenesis requires co-ordination of multiple signalling inputs to regulate the behaviour of endothelial cells (ECs) as they form vascular networks. Vascular endothelial growth factor (VEGF) is essential for angiogenesis and induces downstream signalling pathways including increased cytosolic calcium levels. Here we show that transmembrane protein 33 (tmem33), which has no known function in multicellular organisms, is essential to mediate effects of VEGF in both zebrafish and human ECs. We find that tmem33 localises to the endoplasmic reticulum in zebrafish ECs and is required for cytosolic calcium oscillations in response to Vegfa. tmem33-mediated endothelial calcium oscillations are critical for formation of endothelial tip cell filopodia and EC migration. Global or endothelial-cell-specific knockdown of tmem33 impairs multiple downstream effects of VEGF including ERK phosphorylation, Notch signalling and embryonic vascular development. These studies reveal a hitherto unsuspected role for tmem33 and calcium oscillations in the regulation of vascular development.
Site-specific manipulation of Arabidopsis loci using CRISPR-Cas9 SunTag systems
Authors: Papikian Ashot , Liu Wanlu , Gallego-Bartolomé Javier , Jacobsen Steven E.
Published: February 2019

Understanding genomic functions requires site-specific manipulation of loci via efficient protein effector targeting systems. However, few approaches for targeted manipulation of the epigenome are available in plants. Here, we adapt the dCas9-SunTag system to engineer targeted gene activation and DNA methylation in Arabidopsis. We demonstrate that a dCas9-SunTag system utilizing the transcriptional activator VP64 drives robust and specific activation of several loci, including protein coding genes and transposable elements, in diverse chromatin contexts. In addition, we present a CRISPR-based methylation targeting system for plants, utilizing a SunTag system with the catalytic domain of the Nicotiana tabacum DRM methyltransferase, which efficiently targets DNA methylation to specific loci, including the FWA promoter, triggering a developmental phenotype, and the SUPERMAN promoter. These SunTag systems represent valuable tools for the site-specific manipulation of plant epigenomes.
Ultrathin Co9S8 nanosheets vertically aligned on N,S/rGO for low voltage electrolytic water in alkaline media
Authors: Liu Huan , Xu Cheng-Yan , Du Yue , Ma Fei-Xiang , Li Yue , Yu Jing , Zhen Liang
Published: February 2019

Development of hydrogen as clean and efficient energy carrier for future is imperative. Water electrolysis, is considered as one of the most promising ways to realize large-scaled hydrogen production. However, a big obstacle of it is to reduce the electric energy consumption for water oxidation in the anode. Engineering of hierarchical architectures on the electrocatalysts could provide abundant active sites and thus boost the sluggish reaction kinetics of water oxidation. Herein, a sequential synthesis method is developed forin-situgrowth of ultrathin Co9S8nanosheets vertically aligned on N and S co-doped reduced graphene oxide (Co9S8/N,S-rGO) as novel and efficient electrocatalysts for water splitting. This architecture with vertically aligned ultrathin Co9S8nanosheets on N,S/rGO is adopted to facilitate the electron transport and exposure of active sites. Benefiting from the synergetic catalysis between Co9S8nanosheets and N,S/rGO, Co9S8/N,S-rGO presents remarkable electrocatalytic activity towards oxygen evolution with a low overpotential (266 mV to achieve current density of 10 mA cm−2), small Tafel slope of 75.5 mV dec−1, and good durability in alkaline medium. This remarkable OER electrocatalytic activity is outperforms most of the known noble-metal-free electrocatalysts.