bluuebunny/crossref_metadata_2025 huggingface dataset:
Worldsheet instantons and the amplitude for string pair production in an external field as a WKB exact functional integral
Authors: Gordon James , Semenoff Gordon W.
Published: May 2018

Abstract

We revisit the problem of charged string pair creation in a constant external electric field. The string states are massive and creation of pairs from the vacuum is a tunnelling process, analogous to the Schwinger process where charged particle-anti-particle pairs are created by an electric field. We find the instantons in the worldsheet sigma model which are responsible for the tunnelling events. We evaluate the sigma model partition function in the multi-instanton sector in the WKB approximation which keeps the classical action and integrates the quadratic fluctuations about the solution. We find that the summation of the result over all multi-instanton sectors reproduces the known amplitude. This suggests that corrections to the WKB limit must cancel. To show that they indeed cancel, we identify a fermionic symmetry of the sigma model which occurs in the instanton sectors and which is associated with collective coordinates. We demonstrate that the action is symmetric and that the interaction action is an exact form. These conditions are sufficient for localization of the worldsheet functional integral onto its WKB limit.
Soft thermal contributions to 3-loop gauge coupling
Authors: Laine M. , Schicho P. , Schröder Y.
Published: May 2018

Abstract

We analyze 3-loop contributions to the gauge coupling felt by ultrasoft (“magnetostatic”) modes in hot Yang-Mills theory. So-called soft/hard terms, originating from dimension-six operators within the soft effective theory, are shown to cancel 1097/1098 of the IR divergence found in a recent determination of the hard 3-loop contribution to the soft gauge coupling. The remaining 1/1098 originates from ultrasoft/hard contributions, induced by dimension-six operators in the ultrasoft effective theory. Soft 3-loop contributions are likewise computed, and are found to be IR divergent, rendering the ultrasoft gauge coupling non-perturbative at relative order

$$ \mathcal{O}\left({\alpha}_{\mathrm{s}}^{3/2}\right) $$

O

α
s

3
/
2

. We elaborate on the implications of these findings for effective theory studies of physical observables in thermal QCD.
Conformal bootstrap at large charge
Authors: Jafferis Daniel , Mukhametzhanov Baur , Zhiboedov Alexander
Published: May 2018

Abstract

We consider unitary CFTs with continuous global symmetries in d > 2. We consider a state created by the lightest operator of large charge Q ≫ 1 and analyze the correlator of two light charged operators in this state. We assume that the correlator admits a well-defined large Q expansion and, relatedly, that the macroscopic (thermodynamic) limit of the correlator exists. We find that the crossing equations admit a consistent truncation, where only a finite number N of Regge trajectories contribute to the correlator at leading nontrivial order. We classify all such truncated solutions to the crossing. For one Regge trajectory N = 1, the solution is unique and given by the effective field theory of a Goldstone mode. For two or more Regge trajectories N ≥ 2, the solutions are encoded in roots of a certain degree N polynomial. Some of the solutions admit a simple weakly coupled EFT description, whereas others do not. In the weakly coupled case, each Regge trajectory corresponds to a field in the effective Lagrangian.
Soft gluon evolution and non-global logarithms
Authors: Martínez René Ángeles , De Angelis Matthew , Forshaw Jeffrey R. , Plätzer Simon , Seymour Michael H.
Published: May 2018

Abstract

We consider soft-gluon evolution at the amplitude level. Our evolution algorithm applies to generic hard-scattering processes involving any number of coloured partons and we present a reformulation of the algorithm in such a way as to make the cancellation of infrared divergences explicit. We also emphasise the special role played by a Lorentz-invariant evolution variable, which coincides with the transverse momentum of the latest emission in a suitably defined dipole zero-momentum frame. Handling large colour matrices presents the most significant challenge to numerical implementations and we present a means to expand systematically about the leading colour approximation. Specifically, we present a systematic procedure to calculate the resulting colour traces, which is based on the colour flow basis. Identifying the leading contribution leads us to re-derive the Banfi-Marchesini-Smye equation. However, our formalism is more general and can systematically perform resummation of contributions enhanced by the t’Hooft coupling α

s

N ∼ 1, along with successive perturbations that are parametrically suppressed by powers of 1/N . We also discuss how our approach relates to earlier work.
A highly glucose-tolerant GH1 β-glucosidase with greater conversion rate of soybean isoflavones in monogastric animals
Authors: Cao Huifang , Zhang Yueqi , Shi Pengjun , Ma Rui , Yang Hong , Xia Wei , Cui Ying , Luo Huiying , Bai Yingguo , Yao Bin
Published: May 2018

In the feed industry, β-glucosidase has been widely used in the conversion of inactive and bounded soybean isoflavones into active aglycones. However, the conversion is frequently inhibited by the high concentration of intestinal glucose in monogastric animals. In this study, a GH1 β-glucosidase (AsBG1) with high specific activity, thermostability and glucose tolerance (IC50 = 800 mM) was identified. It showed great glucose tolerance against substrates with hydrophobic aryl ligands (such as pNPG and soy isoflavones). Using soybean meal as the substrate, AsBG1 exhibited higher hydrolysis efficiency than the GH3 counterpart Bgl3A with or without the presence of glucose in the reaction system. Furthermore, it is the first time to find that the endogenous β-glucosidase of soybean meal, mostly belonging to GH3, plays a role in the hydrolysis of soybean isoflavones and is highly sensitive to glucose. These findings lead to a conclusion that the GH1 rather than GH3 β-glucosidase has prosperous application advantages in the conversion of soybean isoflavones in the feed industry.
Tailoring a training based on the Mental Health Gap Action Programme (mhGAP) Intervention Guide (IG) to Tunisia: process and relevant adaptations
Authors: Spagnolo Jessica , Champagne François , Leduc Nicole , Melki Wahid , Guesmi Imen , Bram Nesrine , Guisset Ann-Lise , Piat Myra , Laporta Marc , Charfi Fatma
Published: May 2018

Background

In order to make mental health services more accessible, the Tunisian Ministry of Health, in collaboration with the School of Public Health at the University of Montreal, the World Health Organization office in Tunisia and the Montreal World Health Organization-Pan American Health Organization Collaborating Center for Research and Training in Mental Health, implemented a training programme based on the Mental Health Gap Action Programme (mhGAP) Intervention Guide (IG) (version 1.0), developed by the World Health Organization. This article describes the phase prior to the implementation of the training, which was offered to general practitioners working in primary care settings in the Greater Tunis area of Tunisia.

Methods

The phase prior to implementation consisted of adapting the standard mhGAP-IG (version 1.0) to the local primary healthcare context. This adaptation process, an essential step before piloting the training, involved discussions with stakeholder groups, as well as field observations.

Results

Through the adaptation process, we were able to make changes to the standard training format and material. In addition, the process helped uncover systemic barriers to effective mental health care.

Conclusions

Targeting these barriers in addition to implementing a training programme may help reduce the mental health treatment gap, and promote implementation that is successful and sustainable.
Secondary crossflow instability through global analysis of measured base flows
Authors: Groot Koen J. , Serpieri Jacopo , Pinna Fabio , Kotsonis Marios
Published: May 2018

A combined experimental and numerical approach to the analysis of the secondary stability of realistic swept-wing boundary layers is presented. Global linear stability theory is applied to experimentally measured base flows. These base flows are three-dimensional laminar boundary layers subject to spanwise distortion due to the presence of primary stationary crossflow vortices. A full three-dimensional description of these flows is accessed through the use of tomographic particle image velocimetry (PIV). The stability analysis solves for the secondary high-frequency modes of type I and type II, ultimately responsible for turbulent breakdown. Several pertinent parameters arising from the application of the proposed methodology are investigated, including the mean flow ensemble size and the measurement domain extent. Extensive use is made of the decomposition of the eigensolutions into the terms of the Reynolds–Orr equation, allowing insight into the production and/or destruction of perturbations from various base flow features. Stability results demonstrate satisfactory convergence with respect to the mean flow ensemble size and are independent of the handling of the exterior of the measurement domain. The Reynolds–Orr analysis reveals a close relationship between the type I and type II instability modes with spanwise and wall-normal gradients of the base flow, respectively. The structural role of the in-plane velocity components in the perturbation growth, topology and sensitivity is identified. Using the developed framework, further insight is gained into the linear growth mechanisms and later stages of transition via the primary and secondary crossflow instabilities. Furthermore, the proposed methodology enables the extension and enhancement of the experimental measurement data to the pertinent instability eigenmodes. The present work is the first demonstration of the use of a measured base flow for stability analysis applied to the swept-wing boundary layer, directly avoiding the modelling of the primary vortices receptivity processes.
Simple Trinitarianism and empty names
Authors: KLEINSCHMIDT SHIEVA
Published: May 2018

According to Simple Trinitarianism, God is mereologically simple, and the Father, Son, and Holy Spirit are not identified with any entities in our ontology. Thus the Simple Trinitarian is able to avoid conflating Persons or multiplying Gods, and does not have to identify the Persons with minor entities or entities partly disjoint from God. However, to maintain that Trinitarian sentences are nonetheless true, the Simple Trinitarian will need a non-standard semantics. I explore one option for this, involving taking ‘the Father’, ‘the Son’, and ‘the Holy Spirit’ to be empty names. By adopting a positive, Free Logic, we can take these names to make semantic contributions and play roles in true sentences, while blocking problematic inferences.
Blind to Chains? The Potential of Bioarchaeology for Identifying the Enslaved of Roman Britain
Authors: Redfern Rebecca C.
Published: May 2018

This research explores the contribution bioarchaeology can make to the study of slavery in Roman Britain, responding to the calls by Webster and colleagues for the greater use of osteological and scientific techniques in this endeavour. It reviews the evidence for the bodies of the enslaved in the primary sources and bioarchaeological evidence from the New World and the Roman Empire. The paper aims to establish patterns of physiological stress and disease, which could be used to reconstruct osteobiographies of these individuals, and applies these findings to bioarchaeological evidence from Britain. It concludes that at the present time, it may not be possible for us to successfully separate out the enslaved from the poor or bonded labourers, because their life experiences were very similar. Nevertheless, these people are overlooked in the archaeological record, so unless we attempt to search for them in the extant evidence, the life experiences of the majority of the Romano-British population who were vital to its economy will remain lost to us.
A Low Complexity Integrated Navigation System for Underwater Vehicles
Authors: Emami Mehdi , Taban Mohammad Reza
Published: May 2018

This paper proposes a simplified algorithm for reducing the computational load of the conventional underwater integrated navigation system. The system usually comprises a three-dimensional accelerometer, a three-dimensional gyroscope, a three-dimensional Doppler Velocity Log (DVL) and a data fusion algorithm, such as a Kalman Filter (KF). Since the expected variations of roll, pitch and depth are small, these quantities are assumed to be constant, and the proposed system is designed in a two-dimensional form. Due to the low speed of the vehicle, the nonlinear dynamic equation of the velocity can be simplified in a linear form. We also simplify the conventional KF in order to avoid matrix multiplications and matrix inversions. The performance of the designed system is evaluated in a sea trial by an Autonomous Underwater Vehicle (AUV). The results show that the proposed system can significantly reduce the computational load of the conventional integrated navigation system without a significant reduction in position and velocity accuracy.
A 3D, performance-driven generative design framework: automating the link from a 3D spatial grammar interpreter to structural finite element analysis and stochastic optimization
Authors: Zimmermann Luca , Chen Tian , Shea Kristina
Published: May 2018

Since the introduction of spatial grammars 45 years ago, numerous grammars have been developed in a variety of fields from architecture to engineering design. Their benefits for solution space exploration when computationally implemented and combined with optimization have been demonstrated. However, there has been limited adoption of spatial grammars in engineering applications for various reasons. One main reason is the missing, automated, generalized link between the designs generated by the spatial grammar and their evaluation through finite-element analysis (FEA). However, the combination of spatial grammars with optimization and simulation has the advantage over continuous structural topology optimization in that explicit constraints, for example, modeling style and fabrication processes, can be included in the spatial grammar. This paper discusses the challenges in providing a generalized approach by demonstrating the implementation of a framework that combines a three-dimensional spatial grammar interpreter with automated FEA and stochastic optimization using simulated annealing (SA). Guidelines are provided for users to design spatial grammars in conjunction with FEA and integrate automatic application of boundary conditions. A simulated annealing method for use with spatial grammars is also presented including a new method to select rules through a neighborhood definition. To demonstrate the benefits of the framework, it is applied to the automated design and optimization of spokes for inline skate wheels. This example highlights the advantage of spatial grammars for modeling style and additive manufacturing (AM) constraints within the generative system combined with FEA and optimization to carry out topology and shape optimization. The results verify that the framework can generate structurally optimized designs within the style and AM constraints defined in the spatial grammar, and produce a set of topologically diverse, yet valid design solutions.
Algorithmic complexity of shape grammar implementation
Authors: Wortmann Thomas , Stouffs Rudi
Published: May 2018

Computer-based shape grammar implementations aim to support creative design exploration by automating rule-application. This paper reviews existing shape grammar implementations in terms of their algorithmic complexity, extends the definition of shape grammars with sets of transformations for rule application, categorizes (parametric and non-parametric) sets of transformations, and analyses these categories in terms of the resulting algorithmic complexity. Specifically, it describes how different sets of transformations admit different numbers of targets (i.e., potential inputs) for rule application. In the non-parametric case, this number is quadratic or cubic, while in the parametric case, it can be non-polynomial, depending on the size of the target shape. The analysis thus yields lower bounds for the algorithmic complexity of shape grammar implementations that hold independently of the employed algorithm or data structure. Based on these bounds, we propose novel matching algorithms for non-parametric and parametric shape grammar implementation and analyze their complexity. The results provide guidance for future, general-purpose shape grammar implementations for design exploration.
Generic grammars for design domains
Authors: Beirão José , Duarte José P.
Published: May 2018

Shape grammars have been developed to codify a specific type of artifact – Queen Anne houses, Buffalo bungalows – or the style of a particular designer – Andrea Palladio, Frank Lloyd Wright, or Álvaro Siza Vieira. However, these specific grammars fail to encode recurrent design moves or features that are above the particularities of a specific design style or the idiosyncrasies of a specific designer and, therefore, are common to a larger category of designs and maybe reutilized and incorporated in the definition of new, specific design languages. To overcome these limitations, the notion of generic grammars for defining design domains is introduced. Its application to the urban design domain is illustrated by showing a generic grammar implementation resulting in a City Information Modeling platform composed of a parametric design interface connected to a geographic database.
REJET, FASCINATION, UTILISATION: LA RENAISSANCE ET LA PENSEE ARABE
Authors: Biard Joël
Published: May 2018

L'ouvrage de Dag Nikolaus Hasse ouvre à nouveau le dossier de la présence et de
l'importance de la science et de la philosophie arabes à la Renaissance. Il
estime que cette question a trop souvent été traitée de façon partisane, soit
pour valoriser a priori l'importance de la pensée arabe dans le
développement des sciences en Occident, soit pour valider a
posteriori son rejet. Il convient de reprendre le problème sur des
bases factuelles, voire quantitatives (éditions, diffusion, etc.).
The Italian Translation of Exner’s FQ Tables
Authors: Angelino Luca , Ciliberti Alessandra
Published: May 2018

Abstract. The article takes into consideration the four Italian translations (2003, 2007, 2016, 2017) of the Rorschach Comprehensive System Form Quality Tables ( Exner, 2001 ), with reference to the original English version, highlighting the urgency to verify a number of possible errors that – if proven – would be necessary to rectify. In light of these considerations, we underline the need for an Italian critical edition, as a step toward a shared standard for a scientific instrument that must insure uniformity of results among Comprehensive System users.
Interannual Variability of the Daytime Equatorial Ionospheric Electric Field
Authors: Yamazaki Yosuke , Stolle Claudia , Matzka Jürgen , Liu Huixin , Tao Chihiro
Published: May 2018

Understanding the variability of the ionosphere is important for the prediction of space weather and climate. Recent studies have shown that forcing from the lower atmosphere plays a significant role for the short‐term (day‐to‐day) variability of the low‐latitude ionosphere. The present study aims to assess the importance of atmospheric forcing for the variability of the daytime equatorial ionospheric electric field on the interannual (year‐to‐year) time scale. Magnetic field measurements from Huancayo (12.05°S, 75.33°W) are used to augment the equatorial vertical plasma drift velocity (VZ) measurements from the Jicamarca Unattended Long‐term Investigations of the Ionosphere and Atmosphere radar during 2001–2016. VZ can be regarded as a measure of the zonal electric field. After removing the seasonal variation of ∼10 m/s, midday values of VZ show an interannual variation of ∼2 m/s with an oscillation period of 2–3 years. No evidence of solar cycle influence is found. The Ground‐to‐topside Atmosphere‐Ionosphere model for Aeronomy, which takes into account realistic atmospheric variability below 30 km, reproduces the pattern of the observed interannual variation without having to include variable forcing from the magnetosphere. The results indicate that lower atmospheric forcing plays a dominant role for the observed interannual variability of VZ at 1200 local time.
Atmospheric Mechanisms for MJO Decay Over the Maritime Continent
Authors: DeMott Charlotte A. , Wolding Brandon O. , Maloney Eric D. , Randall David A.
Published: May 2018

Eastward propagating Madden‐Julian oscillation (MJO) events that develop in the Indian Ocean from November to April are separated into events whose convective anomalies do and do not propagate across the Maritime Continent (MC). Propagating (P) events are divided into strong (sP) and weak (wP) subsets based on the initial amplitudes of their convective anomalies. Eastward decaying (ED) MJO events have initial amplitudes similar to those of wP events. Roughly half of all MJO events encounter westward propagating transient dry precursor (TDP) signals over the MC. These TDPs, which are external to the MJO circulation system, overwhelm the weak, eastward propagating moist anomaly in ED events, leading to MJO termination. In wP events, the MJO moist anomaly is stronger than the TDP dry anomaly, and the MJO propagates beyond the MC. ED MJO events that do not encounter TDPs decay because of insufficient moistening in the southern MC region. The background states of TDP‐ and non‐TDP‐affected MJO events resemble La Niña and El Niño conditions, respectively. The regional regulation of TDP activity and background moisture gradients by El Niño–Southern Oscillation can both be understood in terms of the zonal shift and the meridional expansion or contraction of Warm Pool moisture in response to El Niño–Southern Oscillation sea surface temperature anomalies. Our results demonstrate that modulation of TDPs by the background state moisture can affect the MJO in a manner that reinforces its propagation or decay via the interaction of MJO circulation anomalies and background moisture gradients.
Inversion of Multifrequency Data With the Cross‐Correlated Contrast Source Inversion Method
Authors: Sun Shilong , Kooij Bert‐Jan , Yarovoy Alexander G.
Published: May 2018

Cross‐correlated contrast source inversion (CC‐CSI) is a nonlinear iterative inversion method that is proposed recently for solving the inverse scattering problems. In CC‐CSI, a cross‐correlated error is constructed and introduced to the cost functional, which improves the inversion ability when compared to the classical design of the cost functional by exploiting the mismatch between the data error and state error. In this paper, the multifrequency inversion for electromagnetic waves is considered and a multifrequency version of CC‐CSI is proposed. Numerical and experimental inversion results of both transverse magnetic and transverse electric polarization demonstrate that when multifrequency data are available, CC‐CSI still outperforms the multiplicative‐regularized CSI method in the inversion of more complicated scatterers.
White House Seeks Input to Update Space Weather Strategy
Authors: Jonas Seth , Murtagh William
Published: May 2018

Space weather can affect many technologies and infrastructures that society relies on. The White House seeks public input to inform the next steps to better prepare the Nation for this hazard.
The Intensity, Directionality, and Statistics of Underwater Noise From Melting Icebergs
Authors: Glowacki Oskar , Deane Grant B. , Moskalik Mateusz
Published: May 2018

Freshwater fluxes from melting icebergs and glaciers are important contributors to both sea level rise and anomalies of seawater salinity in polar regions. However, the hazards encountered close to icebergs and glaciers make it difficult to quantify their melt rates directly, motivating the development of cryoacoustics as a remote sensing technique. Recent studies have shown a qualitative link between ice melting and the accompanying underwater noise, but the properties of this signal remain poorly understood. Here we examine the intensity, directionality, and temporal statistics of the underwater noise radiated by melting icebergs in Hornsund Fjord, Svalbard, using a three‐element acoustic array. We present the first estimate of noise energy per unit area associated with iceberg melt and demonstrate its qualitative dependence on exposure to surface current. Finally, we show that the analysis of noise directionality and statistics makes it possible to distinguish iceberg melt from the glacier terminus melt.
Observations of Mud‐Induced Periodic Stratification in a Hyperturbid Estuary
Authors: Becker Marius , Maushake Christian , Winter Christian
Published: May 2018

This study presents new observations of fluid mud transport and of the interaction between mud‐induced stratification and the flow. Data collected in a hyperturbid estuarine tidal channel reveal details of the intratidal entrainment asymmetry, characterized by quasi‐instantaneous entrainment and upstream pumping of mud during flood, and a gradual reduction of layer thickness by shear dispersion during ebb. Rapid restratification early during the flood phase restores the predominant two‐layer structure and delimits the transport period, which is then significantly shorter than the overall flood duration. The hydraulic cross section is reduced, causing an increase of the salinity intrusion into the estuary at the end of the flood. The fluid mud layer occupies on average 40% of the water depth, and stratification exceeds that of highly stratified salt wedge estuaries. These data show how mud‐induced periodic stratification influences flow structure and sediment transport and thereby contribute to the understanding of the dynamics of hyperturbid estuaries.
Interchange Injections at Saturn: Statistical Survey of Energetic H+ Sudden Flux Intensifications
Authors: Azari Abigail R. , Liemohn Michael W. , Jia Xianzhe , Thomsen Michelle F. , Mitchell Donald G. , Sergis Nick , Rymer Abigail M. , Hospodarsky George B. , Paranicas Christopher , Vandegriff Jon
Published: May 2018

We present a statistical study of interchange injections in Saturn's inner and middle magnetosphere focusing on the dependence of occurrence rate and properties on radial distance, partial pressure, and local time distribution. Events are evaluated from over the entirety of the Cassini mission's equatorial orbits between 2005 and 2016. We identified interchange events from CHarge Energy Mass Spectrometer (CHEMS) H+ data using a trained and tested automated algorithm, which has been compared with manual event identification for optimization. We provide estimates of interchange based on intensity, which we use to investigate current inconsistencies in local time occurrence rates. This represents the first automated detection method of interchange, estimation of injection event intensity, and comparison between interchange injection survey results. We find that the peak rates of interchange occur between 7 and 9 Saturn radii and that this range coincides with the most intense events as defined by H+ partial particle pressure. We determine that nightside occurrence dominates as compared to the dayside injection rate, supporting the hypothesis of an inversely dependent instability growth rate on local Pedersen ionospheric conductivity. Additionally, we observe a slight preference for intense events on the dawnside, supporting a triggering mechanism related to large‐scale injections from downtail reconnection. Our observed local time dependence paints a dynamic picture of interchange triggering due to both the large‐scale injection‐driven process and ionospheric conductivity.
Stratospheric Response in the First Geoengineering Simulation Meeting Multiple Surface Climate Objectives
Authors: Richter Jadwiga, H. , Tilmes Simone , Glanville Anne , Kravitz Ben , MacMartin Douglas G. , Mills Michael J. , Simpson Isla R. , Vitt Francis , Tribbia Joseph J. , Lamarque Jean‐Francois
Published: May 2018

We describe here changes in stratospheric dynamics and chemistry in a first century‐long sulfate aerosol geoengineering simulation in which the mean surface temperature and the interhemispheric and equator‐to‐pole surface temperature gradients were kept near their 2020 levels despite the RCP8.5 emission scenario. Simulations were carried out with the Community Earth System Model, version 1 with the Whole Atmosphere Community Climate Model as its atmospheric component [CESM1(WACCM)] coupled to a feedback algorithm controlling the magnitude of sulfur dioxide (SO2) injections at four injection latitudes. We find that, throughout the entire geoengineering simulation, the lower stratospheric temperatures increase by ∼0.19 K per Tg SO2 injection per year or ∼10 K with ∼40 Tg SO2/year total SO2 injection. These temperature changes are associated with a strengthening of the polar jets in the stratosphere and weakening of the mean zonal wind in the lower stratosphere subtropics and throughout the troposphere, associated with weaker storm track activity. In the geoengineering simulation the quasi‐biennial oscillation of the tropical lower stratospheric winds remains close to the presently observed quasi‐biennial oscillation, even for large amounts of SO2 injection. Water vapor in the stratosphere increases substantially: by 25% with ∼20 Tg SO2/year annual injection and by up to 90% with a ∼40 Tg SO2/year injection. Stratospheric column ozone in the geoengineering simulation is predicted to recover to or supersede preozone hole conditions by the end of the century.
miR-338-3p functions as a tumor suppressor in gastric cancer by targeting PTP1B
Authors: Sun Feng , Yu Mengchao , Yu Jing , Liu Zhijian , Zhou Xinyan , Liu Yanqing , Ge Xiaolong , Gao Haidong , Li Mei , Jiang Xiaohong , Liu Song , Chen Xi , Guan Wenxian
Published: May 2018

Gastric cancer (GC) is one of the most common malignant tumors and peritoneal metastasis is the primary cause for advanced GC’s mortality. Protein-tyrosine phosphatase 1B (PTP1B) functions as an oncogene and involves in carcinogenesis and cancer dissemination. However, the function and regulation of PTP1B in GC remain poorly understood. In this study, we found that PTP1B was upregulated in GC tissues and overexpression of PTP1B in vitro promoted cell migration and prevented apoptosis. Then, we predicted that PTP1B was a target of miR-338-3p and we revealed an inverse correlation between miR-338-3p levels and PTP1B protein levels in GC tissues. Next, we verified that PTP1B was inhibited by miR-338-3p via direct targeting to its 3′-untranslated regions. Moreover, overexpression of miR-338-3p in vitro attenuated GC cell migration and promoted apoptosis, and these effects could be partially reversed by reintroduction of PTP1B. Finally, we established an orthotopic xenograft model and a peritoneal dissemination model of GC to demonstrate that miR-338-3p restrained tumor growth and dissemination in vivo by targeting PTP1B. Taken together, our results highlight that PTP1B is an oncogene and is negatively regulated by miR-338-3p in GC, which may provide new insights into novel molecular therapeutic targets for GC.
Ambipolar ferromagnetism by electrostatic doping of a manganite
Authors: Zheng L. M. , Wang X. Renshaw , Lü W. M. , Li C. J. , Paudel T. R. , Liu Z. Q. , Huang Z. , Zeng S. W. , Han Kun , Chen Z. H. , Qiu X. P. , Li M. S. , Yang Shize , Yang B. , Chisholm Matthew F. , Martin L. W. , Pennycook S. J. , Tsymbal E. Y. , Coey J. M. D. , Cao W. W.
Published: May 2018

Complex-oxide materials exhibit physical properties that involve the interplay of charge and spin degrees of freedom. However, an ambipolar oxide that is able to exhibit both electron-doped and hole-doped ferromagnetism in the same material has proved elusive. Here we report ambipolar ferromagnetism in LaMnO3, with electron–hole asymmetry of the ferromagnetic order. Starting from an undoped atomically thin LaMnO3 film, we electrostatically dope the material with electrons or holes according to the polarity of a voltage applied across an ionic liquid gate. Magnetotransport characterization reveals that an increase of either electron-doping or hole-doping induced ferromagnetic order in this antiferromagnetic compound, and leads to an insulator-to-metal transition with colossal magnetoresistance showing electron–hole asymmetry. These findings are supported by density functional theory calculations, showing that strengthening of the inter-plane ferromagnetic exchange interaction is the origin of the ambipolar ferromagnetism. The result raises the prospect of exploiting ambipolar magnetic functionality in strongly correlated electron systems.
Comprehensive epigenetic landscape of rheumatoid arthritis fibroblast-like synoviocytes
Authors: Ai Rizi , Laragione Teresina , Hammaker Deepa , Boyle David L. , Wildberg Andre , Maeshima Keisuke , Palescandolo Emanuele , Krishna Vinod , Pocalyko David , Whitaker John W. , Bai Yuchen , Nagpal Sunil , Bachman Kurtis E. , Ainsworth Richard I. , Wang Mengchi , Ding Bo , Gulko Percio S. , Wang Wei , Firestein Gary S.
Published: May 2018

Epigenetics contributes to the pathogenesis of immune-mediated diseases like rheumatoid arthritis (RA). Here we show the first comprehensive epigenomic characterization of RA fibroblast-like synoviocytes (FLS), including histone modifications (H3K27ac, H3K4me1, H3K4me3, H3K36me3, H3K27me3, and H3K9me3), open chromatin, RNA expression and whole-genome DNA methylation. To address complex multidimensional relationship and reveal epigenetic regulation of RA, we perform integrative analyses using a novel unbiased method to identify genomic regions with similar profiles. Epigenomically similar regions exist in RA cells and are associated with active enhancers and promoters and specific transcription factor binding motifs. Differentially marked genes are enriched for immunological and unexpected pathways, with “Huntington’s Disease Signaling” identified as particularly prominent. We validate the relevance of this pathway to RA by showing that Huntingtin-interacting protein-1 regulates FLS invasion into matrix. This work establishes a high-resolution epigenomic landscape of RA and demonstrates the potential for integrative analyses to identify unanticipated therapeutic targets.
Concurrent and orthogonal gold(I) and ruthenium(II) catalysis inside living cells
Authors: Vidal Cristian , Tomás-Gamasa María , Destito Paolo , López Fernando , Mascareñas José L.
Published: May 2018

The viability of building artificial metabolic pathways within a cell will depend on our ability to design biocompatible and orthogonal catalysts capable of achieving non-natural transformations. In this context, transition metal complexes offer unique possibilities to develop catalytic reactions that do not occur in nature. However, translating the potential of metal catalysts to living cells poses numerous challenges associated to their biocompatibility, and their stability and reactivity in crowded aqueous environments. Here we report a gold-mediated C–C bond formation that occurs in complex aqueous habitats, and demonstrate that the reaction can be translated to living mammalian cells. Key to the success of the process is the use of designed, water-activatable gold chloride complexes. Moreover, we demonstrate the viability of achieving the gold-promoted process in parallel with a ruthenium-mediated reaction, inside living cells, and in a bioorthogonal and mutually orthogonal manner.
Resolution of superluminal signalling in non-perturbative cavity quantum electrodynamics
Authors: Sánchez Muñoz Carlos , Nori Franco , De Liberato Simone
Published: May 2018

Recent technological developments have made it increasingly easy to access the non-perturbative regimes of cavity quantum electrodynamics known as ultrastrong or deep strong coupling, where the light–matter coupling becomes comparable to the bare modal frequencies. In this work, we address the adequacy of the broadly used single-mode cavity approximation to describe such regimes. We demonstrate that, in the non-perturbative light–matter coupling regimes, the single-mode models become unphysical, allowing for superluminal signalling. Moreover, considering the specific example of the quantum Rabi model, we show that the multi-mode description of the electromagnetic field, necessary to account for light propagation at finite speed, yields physical observables that differ radically from their single-mode counterparts already for moderate values of the coupling. Our multi-mode analysis also reveals phenomena of fundamental interest on the dynamics of the intracavity electric field, where a free photonic wavefront and a bound state of virtual photons are shown to coexist.
Postnatal Microstructural Developmental Trajectory of Corpus Callosum Subregions and Relationship to Clinical Factors in Very Preterm Infants
Authors: Teli Radhika , Hay Margaret , Hershey Alexa , Kumar Manoj , Yin Han , Parikh Nehal A.
Published: May 2018

Our objectives were to define the microstructural developmental trajectory of six corpus callosum subregions and identify perinatal clinical factors that influence early development of these subregions in very preterm infants. We performed a longitudinal cohort study of very preterm infants (32 weeks gestational age or younger) (N = 36) who underwent structural MRI and diffusion tensor imaging serially at four time points - before 32, 32, 38, and 52 weeks postmenstrual age. We divided the corpus callosum into six subregions, performed probabilistic tractography, and used linear mixed effects models to evaluate the influence of antecedent clinical factors on its microstructural growth trajectory. The genu and splenium demonstrated the most rapid developmental maturation, exhibited by a steep increase in fractional anisotropy. We identified several factors that favored greater corpus callosum microstructural development, including advancing postmenstrual age, higher birth weight, and college level or higher maternal education. Bronchopulmonary dysplasia, low 5-minute Apgar scores, caffeine therapy/apnea of prematurity and male sex were associated with reduced corpus callosum microstructural integrity/development over the first six months after very preterm birth. We identified a unique postnatal microstructural growth trajectory and associated clinical factor profile for each of the six corpus callosum subregions that is consistent with the heterogeneous functional role of these white matter subregions.
Author Correction: Structure and Distribution of an Unrecognized Interstitium in Human Tissues
Authors: Benias Petros C. , Wells Rebecca G. , Sackey-Aboagye Bridget , Klavan Heather , Reidy Jason , Buonocore Darren , Miranda Markus , Kornacki Susan , Wayne Michael , Carr-Locke David L. , Theise Neil D.
Published: May 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Publisher Correction: Reply to ‘Climate of doubt: a re-evaluation of Büntgen and Di Cosmo’s environmental hypothesis for the Mongol withdrawal from Hungary, 1242 CE’
Authors: Büntgen Ulf , Di Cosmo Nicola
Published: May 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Loss of CENP-F Results in Dilated Cardiomyopathy with Severe Disruption of Cardiac Myocyte Architecture
Authors: Manalo Annabelle , Schroer Alison K. , Fenix Aidan M. , Shancer Zoe , Coogan John , Brolsma Tanner , Burnette Dylan T. , Merryman W. David , Bader David M.
Published: May 2018

Centromere-binding protein F (CENP-F) is a very large and complex protein with many and varied binding partners including components of the microtubule network. Numerous CENP-F functions impacting diverse cellular behaviors have been identified. Importantly, emerging data have shown that CENP-F loss- or gain-of-function has critical effects on human development and disease. Still, it must be noted that data at the single cardiac myocyte level examining the impact of CENP-F loss-of-function on fundamental cellular behavior is missing. To address this gap in our knowledge, we analyzed basic cell structure and function in cardiac myocytes devoid of CENP-F. We found many diverse structural abnormalities including disruption of the microtubule network impacting critical characteristics of the cardiac myocyte. This is the first report linking microtubule network malfunction to cardiomyopathy. Importantly, we also present data demonstrating a direct link between a CENP-F single nucleotide polymorphism (snp) and human cardiac disease. In a proximate sense, these data examining CENP-F function explain the cellular basis underlying heart disease in this genetic model and, in a larger sense, they will hopefully provide a platform upon which the field can explore diverse cellular outcomes in wide-ranging areas of research on this critical protein.
Favipiravir (T-705) protects against Nipah virus infection in the hamster model
Authors: Dawes Brian E. , Kalveram Birte , Ikegami Tetsuro , Juelich Terry , Smith Jennifer K. , Zhang Lihong , Park Arnold , Lee Benhur , Komeno Takashi , Furuta Yousuke , Freiberg Alexander N.
Published: May 2018

Nipah and Hendra viruses are recently emerged bat-borne paramyxoviruses (genus Henipavirus) causing severe encephalitis and respiratory disease in humans with fatality rates ranging from 40–75%. Despite the severe pathogenicity of these viruses and their pandemic potential, no therapeutics or vaccines are currently approved for use in humans. Favipiravir (T-705) is a purine analogue antiviral approved for use in Japan against emerging influenza strains; and several phase 2 and 3 clinical trials are ongoing in the United States and Europe. Favipiravir has demonstrated efficacy against a broad spectrum of RNA viruses, including members of the Paramyxoviridae, Filoviridae, Arenaviridae families, and the Bunyavirales order. We now demonstrate that favipiravir has potent antiviral activity against henipaviruses. In vitro, favipiravir inhibited Nipah and Hendra virus replication and transcription at micromolar concentrations. In the Syrian hamster model, either twice daily oral or once daily subcutaneous administration of favipiravir for 14 days fully protected animals challenged with a lethal dose of Nipah virus. This first successful treatment of henipavirus infection in vivo with a small molecule drug suggests that favipiravir should be further evaluated as an antiviral treatment option for henipavirus infections.
Copy number variants implicate cardiac function and development pathways in earthquake-induced stress cardiomyopathy
Authors: Lacey Cameron J. , Doudney Kit , Bridgman Paul G. , George Peter M. , Mulder Roger T. , Zarifeh Julie J. , Kimber Bridget , Cadzow Murray J. , Black Michael A. , Merriman Tony R. , Lehnert Klaus , Bickley Vivienne M , Pearson John F. , Cameron Vicky A. , Kennedy Martin A.
Published: May 2018

The pathophysiology of stress cardiomyopathy (SCM), also known as takotsubo syndrome, is poorly understood. SCM usually occurs sporadically, often in association with a stressful event, but clusters of cases are reported after major natural disasters. There is some evidence that this is a familial condition. We have examined three possible models for an underlying genetic predisposition to SCM. Our primary study cohort consists of 28 women who suffered SCM as a result of two devastating earthquakes that struck the city of Christchurch, New Zealand, in 2010 and 2011. To seek possible underlying genetic factors we carried out exome analysis, genotyping array analysis, and array comparative genomic hybridization on these subjects. The most striking finding was the observation of a markedly elevated rate of rare, heterogeneous copy number variants (CNV) of uncertain clinical significance (in 12/28 subjects). Several of these CNVs impacted on genes of cardiac relevance including RBFOX1, GPC5, KCNRG, CHODL, and GPBP1L1. There is no physical overlap between the CNVs, and the genes they impact do not appear to be functionally related. The recognition that SCM predisposition may be associated with a high rate of rare CNVs offers a novel perspective on this enigmatic condition.
Hepatoprotective effects of Auricularia cornea var. Li. polysaccharides against the alcoholic liver diseases through different metabolic pathways
Authors: Wang Xiuxiu , Lan Yufei , Zhu Yongfa , Li Shangshang , Liu Min , Song Xinling , Zhao Huajie , Liu Weiru , Zhang Jianjun , Wang Shouxian , Jia Le
Published: May 2018

The present work was designed to evaluate the antioxidation and hepatoprotective effects of Auricularia cornea var. Li. polysaccharides (APS) and enzymatic-extractable APS (EAPS) on the acute alcohol-induced alcoholic liver diseases (ALD). The in vitro antioxidant activities demonstrated that both APS and EAPS had strong reducing power and potential effects on scavenging reactive oxygen species. The in vivo mice experiments showed that the pretreatment with APS or EAPS showed potential hepatoprotective effects on the ALD possibly by increasing the antioxidant activities, reducing the lipid peroxidation, improving the alcohol metabolism, inhibiting the expression levels of inflammatory mediators and preventing the alcohol-induced histopathological alterations. In addition, the fourier-transform infrared (FT-IR), 1H and 13C nuclear magnetic resonance spectroscopy (NMR) and gas chromatography (GC) had been analyzed to obtained the primarily characteristics. The results indicated that abundant xylose and glucose contents probably had potential effects on possessing the bioactivities. The findings suggested that the A. cornea var. Li. might be considered as promising natural resource on exploring clinical drugs for the prevention and treatment with ALD and its complications.
Effects of cold acclimation and dsRNA injections on Gs1l gene splicing in Drosophila montana
Authors: Hopkins David , Envall Tapio , Poikela Noora , Pentikäinen Olli T. , Kankare Maaria
Published: May 2018

Alternative splicing, in which one gene produce multiple transcripts, may influence how adaptive genes respond to specific environments. A newly produced transcriptome of Drosophila montana shows the Gs1-like (Gs1l) gene to express multiple splice variants and to be down regulated in cold acclimated flies with increased cold tolerance. Gs1l’s effect on cold tolerance was further tested by injecting cold acclimated and non-acclimated flies from two distantly located northern and southern fly populations with double stranded RNA (dsRNA) targeting Gs1l. While both populations had similar cold acclimation responses, dsRNA injections only effected the northern population. The nature of splicing expression was then investigated in the northern population by confirming which Gs1l variants are present, by comparing the expression of different gene regions and by predicting the protein structures of splices using homology modelling. We find different splices of Gs1l not only appear to have independent impacts on cold acclimation but also elicit different effects in populations originating from two very different environments. Also, at the protein level, Gs1l appears homologous to the human HDHD1A protein and some splices might produce functionally different proteins though this needs to be verified in future studies by measuring the particular protein levels. Taken together, Gs1l appears to be an interesting new candidate to test how splicing influences adaptations.