bluuebunny/crossref_metadata_2025 huggingface dataset:
Chronic immobilization stress primes the hippocampal opioid system for oxycodone‐associated learning in female but not male rats
Authors: Reich Batsheva , Zhou Yan , Goldstein Ellen , Srivats Sudarshan S. , Contoreggi Natalina H. , Kogan Joshua F. , McEwen Bruce S. , Kreek Mary Jeanne , Milner Teresa A. , Gray Jason D.
Published: January 2019

In adult female, but not male, Sprague Dawley rats, chronic immobilization stress (CIS) increases mossy fiber (MF) Leu‐Enkephalin levels and redistributes delta‐ and mu‐opioid receptors (DORs and MORs) in hippocampal CA3 pyramidal cells and GABAergic interneurons to promote excitation and learning processes following subsequent opioid exposure. Here, we demonstrate that CIS females, but not males, acquire conditioned place preference (CPP) to oxycodone and that CIS “primes” the hippocampal opioid system in females for oxycodone‐associated learning. In CA3b, oxycodone‐injected (Oxy) CIS females relative to saline‐injected (Sal) CIS females exhibited an increase in the cytoplasmic and total densities of DORs in pyramidal cell dendrites so that they were similar to Sal‐ and Oxy‐CIS males. Consistent with our earlier studies, Sal‐ and Oxy‐CIS females but not CIS males had elevated DOR densities in MF‐CA3 dendritic spines, which we have previously shown are important for opioid‐mediated long‐term potentiation. In the dentate gyrus, Oxy‐CIS females had more DOR‐labeled interneurons than Sal‐CIS females. Moreover, Sal‐ and Oxy‐CIS females compared to both groups of CIS males had elevated levels of DORs and MORs in GABAergic interneuron dendrites, suggesting capacity for greater synthesis or storage of these receptors in circuits important for opioid‐mediated disinhibition. However, more plasmalemmal MORs were on large parvalbumin‐containing dendrites of Oxy‐CIS males compared to Sal‐CIS males, suggesting a limited ability for increased granule cell disinhibition. These results suggest that low levels of DORs in MF‐CA3 synapses and hilar GABAergic interneurons may contribute to the attenuation of oxycodone CPP in males exposed to CIS.
Improving farm efficiency of interacting vertical‐axis wind turbines through wake deflection using pitched struts
Authors: Mendoza Victor , Goude Anders
Published: January 2019

This work presents a numerical study of the obtained performance and the resulting flow field between two interacting large scale vertical‐axis wind turbines (VAWTs), under the influence of a deflected wake through the struts pitching of the upwind turbine. The configuration consists of two VAWTs aligned in the direction of the incoming flow in which a wide range of fixed struts pitching angles in the upwind turbine have been investigated. The main goal is to evaluate the influence of the wake deflection on the turbines performance while they are operating at their optimal tip speed ratio (TSR), and to reproduce the most relevant phenomena involved in the flow pattern of the interacting wake. Arrangements with cross‐stream offsets have also been tested for quantifying the contribution of this modification into the overall performance. For this purpose, an actuator line model (ALM) has been implemented using the open‐source CFD library OpenFOAM in order to solve the governing equations and to calculate the resulting flow. The Large eddy simulation (LES) approach is considered to reproduce the turbulence flow effects. A preliminary study to identify the optimal TSR of the interacting downwind turbine has been investigated.
The phenomenology of electric dipole moments in models of scalar leptoquarks
Authors: Dekens W. , de Vries J. , Jung M. , Vos K. K.
Published: January 2019

Abstract

We study the phenomenology of electric dipole moments (EDMs) induced in various scalar leptoquark models. We consider generic leptoquark couplings to quarks and leptons and match to Standard Model effective field theory. After evolving the resulting operators to low energies, we connect to EDM experiments by using up-to-date hadronic, nuclear, and atomic matrix elements. We show that current experimental limits set strong constraints on the possible CP-violating phases in leptoquark models. Depending on the quarks and leptons involved in the interaction, the existing searches for EDMs of leptons, nucleons, atoms, and molecules all play a role in constraining the CP-violating couplings. We discuss the impact of hadronic and nuclear uncertainties as well as the sensitivities that can be achieved with future EDM experiments. Finally, we study the impact of EDM constraints on a specific leptoquark model that can explain the recent B-physics anomalies.
Nonlinear chiral transport from holography
Authors: Bu Yanyan , Demircik Tuna , Lublinsky Michael
Published: January 2019

Abstract

Nonlinear transport phenomena induced by the chiral anomaly are explored within a 4D field theory defined holographically as U(1)
V
× U(1)
A
Maxwell-Chern-Simons theory in Schwarzschild-AdS
5. First, in presence of external electromagnetic fields, a general form of vector and axial currents is derived. Then, within the gradient expansion up to third order, we analytically compute all (over 50) transport coefficients. A wealth of higher order (nonlinear) transport phenomena induced by chiral anomaly are found beyond the Chiral Magnetic and Chiral Separation Effects. Some of the higher order terms are relaxation time corrections to the lowest order nonlinear effects. The charge diffusion constant and dispersion relation of the Chiral Magnetic Wave are found to receive anomaly-induced non-linear corrections due to e/m background fields. Furthermore, there emerges a new gapless mode, which we refer to as Chiral Hall Density Wave, propagating along the background Poynting vector.
Same-sign multilepton signatures of an SU(2)R quintuplet at the LHC
Authors: Agarwalla Sanjib Kumar , Ghosh Kirtiman , Kumar Nilanjana , Patra Ayon
Published: January 2019

Abstract

We study in detail the collider signatures of an SU(2)
R
fermionic quintuplet in the framework of left-right symmetric model in the context of the 13 TeV LHC. Apart from giving a viable dark matter candidate (χ
0), this model provides unique collider imprints in the form of same-sign multileptons through the decays of multi-charged components of the quintuplet. In particular, we consider the scenario where the quintuplet carries (B − L) = 4 charge, allowing for the presence of high charge-multiplicity particles with relatively larger mass differences among them compared to (B − L) = 0 or 2. In this paper, we mainly focus on the same-sign n-lepton signatures (nSSL). We show that with an integrated luminosity of 500 fb−1, the mass of the neutral component,

$$ {M}_{\chi^0} $$

M

χ
0

≤ 480 (800) GeV can be excluded at 95% CL in the 2SSL (3SSL) channel after imposing several selection criteria. We also show that a 5σ discovery is also achievable if

$$ {M}_{\chi^0} $$

M

χ
0

≤ 390 (750) GeV in the 2SSL (3SSL) channel with 1000 fb−1 integrated luminosity.
Reaction time-based Concealed Information Test in eyewitness identification is moderated by picture similarity but not eyewitness cooperation
Authors: Georgiadou Katerina , Chronos Agatha , Verschuere Bruno , Sauerland Melanie
Published: January 2019

The reaction time-based Concealed Information Test (RT-CIT) has high validity in assessing recognition of critical information. Findings on its usefulness for diagnosing face recognition in eyewitnesses are inconsistent. Experiment 1 (N = 82) tested whether closely matching the faces of the probes and irrelevants, as required for a fair lineup, undermines RT-CIT usefulness. Preregistered Experiments 2a and 2b (Ns = 48), tested the role of eyewitness cooperativeness for RT-CIT validity. All participants watched a mock crime video and then completed an RT-CIT. As expected, the usefulness of the RT-CIT was moderated by picture similarity, with better detection for non-matched faces. Unexpectedly, eyewitness cooperation (conceal vs. reveal recognition), did not affect the validity of the RT-CIT. A large CIT effect observed in Experiment 2b further suggested that—even with matched faces—the RT-CIT might be of use when encoding conditions during the crime were favorable. Cases in which witnesses are unwilling or afraid to make an explicit identification might concern another possible application.
Unbalanced multi-drawing urn with random addition matrix
Authors: Rafik Aguech , Olfa Selmi
Published: January 2019

In this paper, we consider a two color multi-drawing urn model. At each discrete time step, we draw uniformly at random a sample of m balls (m≥1) and note their color, they will be returned to the urn together with a random number of balls depending on the sample’s composition. The replacement rule is a 2 × 2 matrix depending on bounded discrete positive random variables. Using a stochastic approximation algorithm and martingales methods, we investigate the asymptotic behavior of the urn after many draws.
Physical therapy pathway and protocol for patients undergoing hematopoietic stem cell transplantation
Authors: Mohammed Jaleel , Aljurf Mahmoud , Althumayri Abdulaziz , Almansour Muntaha , Alghamdi Ahmed , Hamidieh Amir Ali , ElHaddad Alaa , Othman Tarek Ben , Bazarbachi Ali , Almohareb Fahad , Alzahrani Mohsen , Alkindi Salam S. , Alsharif Fahad , Da'na Waleed , Alhashmi Hani , Bekadja Mohamed A. , Al-Shammari Salem H. , Quessar Asma El , Satti Tariq M. , Aljohani Naif , Rasheed Walid , Ghavamzadeh Ardeshir , Chaudhri Naeem , Hashmi Shahrukh K.
Published: January 2019

Background:

Patients undergoing hematopoietic stem cell transplantation (HSCT) are often referred for physical therapy (PT) to help improve their quality of life. However, to our knowledge there is no clear PT pathway to guide therapists and patients before, during, and after HSCT.

Methods:

A comprehensive literature review was carried out exploring the role and benefits of PT in HSCT patients. The current evidence was comlimented with recommendations and opinions from the experts in the field, which included PT's and hematology consultants from PTAGVHD and the EMBMT group.

Result:

A clear pathway and protocol as a working guide for rehabilitation professionals working with the HSCT patient's was developed.

Conclusion:

This paper not only reviews the current evidence on safe PT practice but also puts forward a protocol and pathway for HSCT rehabilitation, highlights the importance of individualized exercise intervention for HSCT patients, and outlines safe practice guidelines for the physical therapists working in this field.
Shape and rheology of droplets with viscous surface moduli
Authors: Narsimhan Vivek
Published: January 2019

We develop perturbation theories to describe the flow dynamics of a droplet with a thin layer of insoluble surfactant whose mechanics are described by interfacial viscosity, i.e. a Boussinesq–Scriven constitutive law. The theories quantify droplet deformation in the limit of small capillary number, large viscosity ratio, or large shear Boussinesq number, to a sufficient level of approximation where one can extract information about nonlinear rheology and droplet breakup. In the first part of this manuscript, we quantify the Taylor deformation parameter and inclination angle in shear and extensional flows, developing expressions that resolve discrepancies between current analytical theories and boundary element simulations. Interestingly, the theories we develop appear to accurately describe the inclination angle of a clean droplet over a wider range of viscosity ratios and capillary numbers than previous works. In the second part of the manuscript, we calculate how interfacial viscosity alters the extra stress of a dilute suspension of droplets, in particular the shear stress, normal stress differences, shear thinning and extensional thickening. The normal stresses are intimately related to the lateral migration of droplets in wall-bound shear flow, and we explore the influence of interfacial viscosity on this phenomenon. We conclude by discussing how one can use these theories to describe droplet breakup, and how one can incorporate additional effects into the perturbation theories such as viscoelastic membranes and/or Marangoni flows.
Nozzle external geometry as a boundary condition for the azimuthal mode selection in an impinging underexpanded jet
Authors: Weightman Joel L. , Amili Omid , Honnery Damon , Edgington-Mitchell Daniel , Soria Julio
Published: January 2019

The role of the external boundary conditions of the nozzle surface on the azimuthal mode selection of impinging supersonic jets is demonstrated for the first time. Jets emanating from thin- and infinite-lipped nozzles at a nozzle pressure ratio of $3.4$ and plate spacing of $5.0D$, where $D$ is the nozzle exit diameter, are investigated using high resolution particle image velocimetry (PIV) and acoustic measurements. Proper orthogonal decomposition is applied to the PIV fields and a difference in dominant instability mode is found. To investigate possible explanations for the change in instability mode, additional nozzle external boundary conditions are investigated, including the addition of acoustic dampening foam. A difference in acoustic feedback path is suggested to be the cause for the change in dominant azimuthal modes between the flows. This is due to the thin-lip case containing a feedback path that is concluded to be closed exclusively by a reflection from the nozzle base surface, rather than directly to the nozzle lip. The ability of the flow to form a feedback path that maximises the impingement tone gain is discussed with consideration of the numerous acoustic feedback paths possible for the given nozzle external boundary conditions.
Collision and breakup of fractal particle agglomerates in a shear flow
Authors: Dizaji Farzad F. , Marshall Jeffrey S. , Grant John R.
Published: January 2019

A computational study was performed both of a single agglomerate and of the collision of two agglomerates in a shear flow. The agglomerates were extracted from a direct numerical simulation of a turbulent agglomeration process, and had the loosely packed fractal structure typical of agglomerate structures formed in turbulent agglomeration processes. The computation was performed using a discrete-element method for adhesive particles with four-way coupling, accounting both for forces between the fluid and the particles (andvice versa) as well as force transmission directly between particles via particle collisions. In addition to understanding and characterizing the particle dynamics, the study focused on illuminating the fluid flow field induced by the agglomerate in the presence of a background shear and the effect of collisions on this particle-induced flow. Perhaps the most interesting result of the current work was the observation that the flow field induced by a particle agglomerate rotating in a shear flow has the form of two tilted vortex rings with opposite-sign circulation. These rings are surrounded by a sea of stretched vorticity from the background shear flow. The agglomerate rotates in the shear flow, but at a slower rate than the ambient fluid elements. In the computations with two colliding agglomerates, we observed cases resulting in agglomerate merger, bouncing and fragmentation. However, the bouncing cases were all observed to also result in an exchange of particles between the two colliding agglomerates, so that they were influenced both by elastic rebound of the agglomerate structures as well as by tearing away of particulate matter between the agglomerates. Overall, the problems of agglomerate–flow interaction and of the collision of two agglomerates in a shear flow are considerably richer in physical phenomena and more complex than can be described by the common approximation that represents each agglomerate by an ‘equivalent sphere’.
Probabilistic size effect law for mode II fracture from critical lengths in snow slab avalanche weak layers
Authors: McCLUNG D. M. , BORSTAD C. P.
Published: January 2019

From field observations, dry snow slab avalanche initiation is associated with fracture within relatively thin weak layers under stronger, cohesive slabs. For risk-based avalanche prediction, it is important to understand the fracture properties of alpine snow. Alpine snow is a quasi-brittle material with a fracture mechanical size effect on nominal shear strength meaning that strength decreases with increasing specimen size. A related size effect is the critical length required for rapid propagation of a shear fracture. In that case, the probability of fracture increases with increasing crack length. In this paper, 45 sets of field-measured critical lengths are presented based on 591 individual tests. From analysis, a probabilistic size effect law based on critical lengths is derived analogous to the deterministic size effect law for nominal shear strength related to fracture mechanics. The new size effect law may be useful in applications, particularly since the critical length is easily measured in the field and it is a principal component of weak layer fracture toughness.
Low-carbohydrate diets and prevalence, incidence and progression of coronary artery calcium in the Multi-Ethnic Study of Atherosclerosis (MESA)
Authors: Hu Tian , Jacobs David R. , Bazzano Lydia A. , Bertoni Alain G. , Steffen Lyn M.
Published: January 2019

The evidence linking low-carbohydrate diets (LCD) to CVD is controversial, and results from epidemiological studies are inconsistent. We aimed to assess the relationship between LCD patterns and coronary artery Ca (CAC) scores from computed tomography in the Multi-Ethnic Study of Atherosclerosis cohort. Our sample included 5614 men and women free of clinical CVD at baseline (2000–2002), who had a FFQ, a baseline measure and ≥1 measure of CAC during follow-up. We excluded those with implausible energy intake or daily physical activity. The overall, animal-based and plant-based LCD scores were calculated based on intakes of macronutrients. Relative risk regression and robust regression models were used to examine the cross-sectional and longitudinal relationship between LCD score quintile and CAC outcomes, after adjustment for multiple cardiovascular risk factors. The mean age of participants was 63 years. The median intakes of total carbohydrate, fat and protein were 53·7, 30·5 and 15·6 % energy/d, respectively. Among 2892 participants with zero CAC scores at baseline, 264 developed positive scores during 2·4-year follow-up (11–59 months). Among those with positive scores at baseline, the median increase in CAC was 47 units over the course of follow-up. The overall, the animal-based and the plant-based LCD scores were not associated with CAC prevalence, incidence and progression. In conclusion, diets low in carbohydrate and high in fat and/or protein, regardless of the sources of protein and fat, were not associated with higher levels of CAC, a validated predictor of cardiovascular events, in this large multi-ethnic cohort.
MATERIAL ENCOUNTERS: KNOTTING CULTURES IN EARLY MODERN PERU AND SPAIN
Authors: HANß STEFAN
Published: January 2019

This article discusses the early modern nexus between feather-work and textiles with a focus on Spanish Peru. Whilst Peruvian feather-work has been defined as pre-Columbian, this article presents new textual, visual, and material evidence that shows its significance in the material culture of colonial Peru, which serves to initiate a broader debate on the dynamics of cultural encounters in the Ibero-American world. I chart the development of craft cultures beyond the moment of the Spanish conquest of the Americas by discussing Peruvian practices of feather manufacturing in relation to the production and usage of textiles in early modern Spain. This approach, I argue, will enable a reconsideration of the dynamics of the Spanish Empire, whose centres and peripheries were linked through circulating objects that constituted a shared material world. In the particular case of feather-work, this was a world that jointly valued the aesthetics of knots and the intricacy of knotting.
Googling Investor Sentiment around the World
Authors: Gao Zhenyu , Ren Haohan , Zhang Bohui
Published: January 2019

We study how investor sentiment affects stock prices around the world. Relying on households’ Google search behavior, we construct a weekly measure of sentiment for 38 countries during 2004–2014. We validate the sentiment index in tests using sports outcomes and show that the sentiment measure is a contrarian predictor of country-level market returns. Furthermore, we document an important role of global sentiment in stock markets.
The Emergence of Antimicrobial Resistance as a Public Matter of Concern: A Swedish History of a “Transformative Event”
Authors: Gröndal Hedvig
Published: January 2019

Argument

This article examines how antimicrobial resistance (AMR) came to be constituted as a matter of public concern in Sweden in conjunction with the development of an inter-professional organization called Strama, founded to promote rational prescription of antibiotics. An outbreak of penicillin-resistant pneumococci in the mid-1990s was crucial for this development, because it brought attention to AMR as an urgent public threat. This outbreak fuelled the constitution of AMR as caused by consumption of antibiotics and as a matter of disease control. As a consequence, Strama was able to mobilize the Swedish health officers responsible for disease control. The outbreak is conceptualized as a “transformative event” – an event that makes an issue and its associated risks concrete and urgent. Transformative events play the crucial role of expediting the transformation of issues into matters of public concern.
Identification, characterization and expression analysis of the chalcone synthase family in the Antarctic moss Pohlia nutans
Authors: Yao Xinghao , Wang Tailin , Wang Huijuan , Liu Hongwei , Liu Shenghao , Zhao Qingang , Chen Kaoshan , Zhang Pengying
Published: January 2019

Mosses have adapted to the Antarctic environment and are an ideal medium for studying plant resistance to abiotic stress. Chalcone synthase is the first committed enzyme in the flavonoid metabolic pathway, which plays an indispensable role in plant resistance to adversity. In this study, six genes (Pn021, PnCHS088, Pn270, PnCHS444, PnCHS768 and Pn847) were identified in the Antarctic moss Pohlia nutans Lindberg transcriptome by reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). Sequence alignment and three-dimensional structure analysis revealed the conserved amino acid residues of the enzymes of the chalcone synthase family, including three catalytic residues (Cys164, His303 and Asn336) and two substrate recognition residues (Phe215 and Phe265). Phylogenetic analysis indicated that PnCHS088, PnCHS444 and PnCHS768 might be chalcone synthase but that Pn021 is more like stilbenecarboxylate synthase. These genes were located at the transition between fungi and advanced plants in the phylogenetic tree. In addition, real-time PCR analysis revealed that the expression profiles of the six P. nutans genes were influenced by diverse abiotic stresses as well as by abscisic acid and methyl jasmonate. The results presented here contribute to the study of the CHS gene family in polar mosses and further reveal the mechanisms underlying the adaptation of mosses to extreme environments.
Health economics methods for public health resource allocation: a qualitative interview study of decision makers from an English local authority
Authors: Frew Emma , Breheny Katie
Published: January 2019

Local authorities in England have responsibility for public health, however, in recent years, budgets have been drastically reduced placing decision makers under unprecedented financial pressure. Although health economics can offer support for decision making, there is limited evidence of it being used in practice. The aim of this study was to undertake in-depth qualitative research within one local authority to better understand the context for public health decision making; what, and how economics evidence is being used; and invite suggestions for how methods could be improved to better support local public health decision making. The study included both observational methods and in-depth interviews. Key meetings were observed and semi-structured interviews conducted with participants who had a decision-making role to explore views on economics, to understand the barriers to using evidence and to invite suggestions for improvements to methods. Despite all informants valuing the use of health economics, many barriers were cited: including a perception of a narrow focus on the health sector; lack of consideration of population impact; and problems with translating long timescales to short term impact. Methodological suggestions included the broadening of frameworks; increased use of natural experiments; and capturing wider non-health outcomes that resonate with the priorities of multiple stakeholders.
Oligocene‐Early Miocene Topographic Relief Generation of Southeastern Tibet Triggered by Thrusting
Authors: Cao Kai , Wang Guocan , Leloup Philippe Hervé , Mahéo Gweltaz , Xu Yadong , van der Beek Pieter A. , Replumaz Anne , Zhang Kexin
Published: January 2019

The timing and mechanisms of uplift in southeastern Tibet remain disputed. To address this debate, we conducted structural and morphological analyses of the Yulong thrust belt; we also reconstruct the cooling and exhumation history of the Jianchuan basin in the hanging wall of the thrust system using inverse thermal modeling of apatite fission‐track and (U‐Th)/He thermochronology data. Our results provide evidence for 2.3–3.2 km of rapid exhumation in the Jianchuan basin between ~28 and ~20 Ma, followed by limited exhumation of less than 0.2 km since then. The magnitude of basin exhumation is consistent with the present‐day topographic step of 1.8–2.4 km across the Yulong and Chenghai thrust belts, as shown by morphometric analysis. We thus infer that the present‐day morphology of the southeastern margin of Tibet results partly from thrusting along the Yulong thrust belt during the Late Oligocene‐Early Miocene. This structure may be the southwest continuation of the Longmen Shan thrust belt, offset by the Xianshuihe fault in the Late Miocene. On a regional scale, the approximate synchronicity of exhumation in the hanging walls of the Yalong‐Yulong and Longmen Shan thrust systems indicates that widespread crustal shortening and thickening took place in southeastern Tibet during the Late Oligocene‐Early Miocene.
Relative Roles of Preconditioning Moistening and Global Circumnavigating Mode on the MJO Convective Initiation During DYNAMO
Authors: Chen Xingchao , Zhang Fuqing
Published: January 2019

The relative importance of preconditioning moistening and global circumnavigating mode in the convective initiation of the October 2011 Madden–Julian Oscillation (MJO) event observed during the Dynamics of the Madden–Julian Oscillation (DYNAMO) field campaign is investigated using a series of convection‐permitting regional model simulations. It is demonstrated that the MJO convective initiation is largely controlled by the global circumnavigating mode at the intraseasonal scales. Rapid moistening closely related to this eastward propagating mode a few days prior to the MJO active phase is crucial to the initiation of deep convection and enhanced rainfall. This moistening process nevertheless cannot be accurately described by the “discharge‐recharge” hypothesis, which speculates the importance a gradual moisture buildup over an approximately 2‐week period leading to the arrival of the active MJO phase.
Simulations of Secondary Farley‐Buneman Instability Driven by a Kilometer‐Scale Primary Wave: Anomalous Transport and Formation of Flat‐Topped Electric Fields
Authors: Young Matthew A. , Oppenheim Meers M. , Dimant Yakov S.
Published: January 2019

Since the 1950s, high frequency and very high frequency radars near the magnetic equator have frequently detected strong echoes caused ultimately by the Farley‐Buneman instability (FBI) and the gradient drift instability (GDI). In the 1980s, coordinated rocket and radar campaigns made the astonishing observation of flat‐topped electric fields coincident with both meter‐scale irregularities and the passage of kilometer‐scale waves. The GDI in the daytime E region produces kilometer‐scale primary waves with polarization electric fields large enough to drive meter‐scale secondary FBI waves. The meter‐scale waves propagate nearly vertically along the large‐scale troughs and crests and act as VHF tracers for the large‐scale dynamics. This work presents a set of hybrid numerical simulations of secondary FBIs, driven by a primary kilometer‐scale GDI‐like wave. Meter‐scale density irregularities develop in the crest and trough of the kilometer‐scale wave, where the total electric field exceeds the FBI threshold, and propagate at an angle near the direction of total Hall drift determined by the combined electric fields. The meter‐scale irregularities transport plasma across the magnetic field, producing flat‐topped electric fields similar to those observed in rocket data and reducing the large‐scale wave electric field to just above the FBI threshold value. The self‐consistent reduction in driving electric field helps explain why echoes from the FBI propagate near the plasma acoustic speed.
Storm Time EMIC Waves Observed by Swarm and Van Allen Probe Satellites
Authors: Wang Hui , He Yangfan , Lühr Hermann , Kistler Lynn , Saikin Anthony , Lund Eric , Ma Shuying
Published: January 2019

The temporal and spatial evolution of electromagnetic ion cyclotron (EMIC) waves during the magnetic storm of 21–29 June 2015 was investigated using high‐resolution magnetic field observations from Swarm constellation in the ionosphere and Van Allen Probes in the magnetosphere. Magnetospheric EMIC waves had a maximum occurrence frequency in the afternoon sector and shifted equatorward during the expansion phase and poleward during the recovery phase. However, ionospheric waves in subauroral regions occurred more frequently in the nighttime than during the day and exhibited less obvious latitudinal movements. During the main phase, dayside EMIC waves occurred in both the ionosphere and magnetosphere in response to the dramatic increase in the solar wind dynamic pressure. Waves were absent in the magnetosphere and ionosphere around the minimum SYM‐H. During the early recovery phase, He+ band EMIC waves were observed in the ionosphere and magnetosphere. During the late recovery phase, H+ band EMIC waves emerged in response to enhanced earthward convection during substorms in the premidnight sector. The occurrence of EMIC waves in the noon sector was affected by the intensity of substorm activity. Both ionospheric wave frequency and power were higher in the summer hemisphere than in the winter hemisphere. Waves were confined to an MLT interval of less than 5 hr with a duration of less than 186 min from coordinated observations. The results could provide additional insights into the spatial characteristics and propagation features of EMIC waves during storm periods.
Effects of Induced Stress on Seismic Waves: Validation Based on Ab Initio Calculations
Authors: Tromp Jeroen , Marcondes Michel L. , Wentzcovitch Renata M. M. , Trampert Jeannot
Published: January 2019

When a continuum is subjected to an induced stress, the equations that govern seismic wave propagation are modified in two ways. First, the equation of conservation of linear momentum gains terms related to the induced deviatoric stress, and, second, the elastic constitutive relationship acquires terms linear in the induced stress. This continuum mechanics theory makes testable predictions with regard to stress‐induced changes in the elastic tensor. Specifically, it predicts that induced compression linearly affects the prestressed moduli with a slope determined by their local adiabatic pressure derivatives and that induced deviatoric stress produces anisotropic compressional and shear wave speeds. In this article we successfully compare such predictions against ab initio mineral physics calculations for NaCl and MgO.
Long‐Term Fog Variation and Its Impact Factors Over Polluted Regions of East China
Authors: Yan Shuqi , Zhu Bin , Kang Hanqing
Published: January 2019

During the past five decades, China has witnessed frequent fog and haze events. Previous studies have revealed that in polluted regions of East China, such as the Beijing‐Tianjin‐Hebei (BTH) region, the Yangtze River Delta (YRD) region, and the Pearl River Delta (PRD) region, fog frequencies are impacted not only by climate change but also by fast urbanization and increasing air pollution. In this study, we find that haze days increased markedly in the three regions. However, fog days showed an initially increasing and then decreasing trend, with the turning point in the 1980s; moreover, the turning point occurred 5–15 years earlier in large cities than in small cities. We further attribute the long‐term fog variations over East China to three factors: regional‐scale climate change, urbanization, and air pollution (aerosol pollution). We quantitatively show that urbanization and aerosol pollution contributed at least 1.6 times more than climate change, and their contributions varied with urban development stages. Fog was dominantly promoted by abundant aerosols (45–85%) during the slow urbanization stage, while it was dominantly inhibited by urban heat island and dry island (53–60%) effects during the rapid urbanization stage. In the 53‐year period, aerosol pollution promoted fog formation (20–40%).
Magnetic Anomalies Within the Crisium Basin: Magnetization Directions, Source Depths, and Ages
Authors: Baek Seul‐Min , Kim Khan‐Hyuk , Garrick‐Bethell Ian , Jin Ho
Published: January 2019

Using Lunar Prospector magnetic field data, we identify four isolated anomalies (CNA, CSA1, CSA1, and CWA) within the Crisium basin. We assume the sources of the anomalies to be buried point dipoles and find that the estimated depths and radial positions are well contained within Crisium's melt pool (∼250‐km radii and ∼100‐km depth). This implies that the anomalies recorded a thermoremanent magnetization in a dynamo field at ∼3.9 Ga. We also find that the anomalies can be classified into two groups (Groups 1 and 2) according to source depths and paleopoles. The sources of Group 1 (CNA and CSA1) are buried at ∼30 km. Estimated paleopoles are located at ∼45°N for CNA and near the equator (∼12°N) CSA1, with remanence acquisition timescale of ∼5 Myr. The sources of Group 2 (CSA2 and CWA) are more deeply buried at ∼55–70 km. Their paleopole positions are close to the present south pole, with a remanence acquisition timescale of ∼15–23 Myr. These variable paleopoles imply that the local field orientation shifted during formation of the anomalies. That is, the Moon may have experienced a ∼14‐Myr‐epoch of complex field geometries. These changes may have arisen from true polar wander driven by impact or internal density changes, or from equatorial dynamo orientations produced by anomalous core heat flux conditions. The long cooling timescales of the anomalies also suggest that they were not magnetized by transient fields produced by impact‐induced stirring of the core.
Potential Vorticity of Saturn's Polar Regions: Seasonality and Instabilities
Authors: Antuñano Arrate , del Río‐Gaztelurrutia Teresa , Sánchez‐Lavega Agustín , Read Peter L. , Fletcher Leigh N.
Published: January 2019

We analyze the potential vorticity of Saturn's polar regions, as it is a fundamental dynamical tracer that enables us to improve our understanding of the dynamics of these regions and their seasonal variability. In particular, we present zonally averaged quasi‐geostrophic potential vorticity maps between 68° planetographic latitude and the poles at altitudes between 500 and 1 mbar for three different epochs: (i) June 2013 (early northern summer) for the north polar region, (ii) December 2008 (late northern winter) for both polar regions, and (iii) October 2006 (southern summer) for the south, computed using temperature profiles retrieved from Cassini Composite Infrared Spectrometer data and wind profiles obtained from Cassini's Imaging Science Subsystem. The results show that quasi‐geostrophic potential vorticity maps are very similar at all the studied epochs, showing positive vorticities at the north and negative at the south, indicative of the dominance of the Coriolis parameter 2Ωsinϕ at all latitudes, except near the pole. The meridional gradients of the quasi‐geostrophic potential vorticity show that dynamical instabilities, mainly due to the barotropic term, could develop at the flanks of the Hexagon at 78°N, the jet at 73.9°S, and on the equatorward flank of both polar jets. There are no differences in potential vorticity gradients between the two hemispheres that could explain why a hexagon forms in the north and not in the south. No seasonal variability of the potential vorticity and its meridional gradient has been found, despite significant changes in the atmospheric temperatures over time.
An Improved Analytical Solution for the Temperature Profile of Ice Sheets
Authors: Rezvanbehbahani Soroush , van der Veen C. J. , Stearns Leigh A.
Published: January 2019

The one‐dimensional steady state analytical solution of the energy conservation equation obtained by Robin (1955, https://doi.org/10.3189/002214355793702028) is frequently used in glaciology. This solution assumes a linear change in surface velocity from a minimum value equal to minus the mass balance at the surface to zero at the bed. Here we show that this assumption of a linear velocity profile leads to large errors in the calculated temperature profile and especially in basal temperature. By prescribing a nonlinear power function of elevation above the bed for the vertical velocity profile arising from use of the Shallow Ice Approximation, we derive a new analytical solution for temperature. We show that the solution produces temperature profiles identical to numerical temperature solutions with the Shallow Ice Approximation vertical velocity near ice divides. We quantify the importance of strain heating and demonstrate that integrating the strain heating and adding it to the geothermal heat flux at the bed is a reasonable approximation for the interior regions. Our analytical solution does not include horizontal advection components, so we compare our solution with numerical solutions of a two‐dimensional advection‐diffusion model and assess the applicability and errors of the analytical solution away from the ice divide. We show that several parameters and assumptions impact the spatial extent of applicability of the new solution including surface mass balance rate and surface temperature lapse rate. We delineate regions of Greenland and Antarctica within which the analytical solution at any depth is likely within 2 K of the actual temperatures with horizontal advection.
Morphology and surface chemistry engineering toward pH-universal catalysts for hydrogen evolution at high current density
Authors: Luo Yuting , Tang Lei , Khan Usman , Yu Qiangmin , Cheng Hui-Ming , Zou Xiaolong , Liu Bilu
Published: January 2019

Large-scale implementation of electrochemical hydrogen production requires several fundamental issues to be solved, including understanding the mechanism and developing inexpensive electrocatalysts that work well at high current densities. Here we address these challenges by exploring the roles of morphology and surface chemistry, and develop inexpensive and efficient electrocatalysts for hydrogen evolution. Three model electrocatalysts are flat platinum foil, molybdenum disulfide microspheres, and molybdenum disulfide microspheres modified by molybdenum carbide nanoparticles. The last catalyst is highly active for hydrogen evolution independent of pH, with low overpotentials of 227 mV in acidic medium and 220 mV in alkaline medium at a high current density of 1000 mA cm−2, because of enhanced transfer of mass (reactants and hydrogen bubbles) and fast reaction kinetics due to surface oxygen groups formed on molybdenum carbide during hydrogen evolution. Our work may guide rational design of electrocatalysts that work well at high current densities.
Control of triboelectric charges on common polymers by photoexcitation of organic dyes
Authors: Cezan S. Doruk , Nalbant Atakan A. , Buyuktemiz Muhammed , Dede Yavuz , Baytekin H. Tarik , Baytekin Bilge
Published: January 2019

Triboelectric charging of insulators, also known as contact charging in which electrical charges develop on surfaces upon contact, is a significant problem that is especially critical for various industries such as polymers, pharmaceuticals, electronics, and space. Several methods of tribocharge mitigation exist in practice; however, none can reach the practicality of using light in the process. Here we show a light-controlled manipulation of triboelectric charges on common polymers, in which the tribocharges are mitigated upon illumination with appropriate wavelengths of light in presence of a mediator organic dye. Our method provides spatial and temporal control of mitigation of static charges on common polymer surfaces by a mechanism that involves photoexcitation of organic dyes, which also allows additional control using wavelength. This control over charge mitigation provides a way to manipulate macroscopic objects by tribocharging followed by light-controlled discharging.
LUBAC controls chromosome alignment by targeting CENP-E to attached kinetochores
Authors: Wu Min , Chang Yan , Hu Huaibin , Mu Rui , Zhang Yucheng , Qin Xuanhe , Duan Xiaotao , Li Weihua , Tu Haiqing , Zhang Weina , Wang Guang , Han Qiuying , Li Ailing , Zhou Tao , Iwai Kazuhiro , Zhang Xuemin , Li Huiyan
Published: January 2019

Faithful chromosome segregation requires proper chromosome congression at prometaphase and dynamic maintenance of the aligned chromosomes at metaphase. Chromosome missegregation can result in aneuploidy, birth defects and cancer. The kinetochore-bound KMN network and the kinesin motor CENP-E are critical for kinetochore-microtubule attachment and chromosome stability. The linear ubiquitin chain assembly complex (LUBAC) attaches linear ubiquitin chains to substrates, with well-established roles in immune response. Here, we identify LUBAC as a key player of chromosome alignment during mitosis. LUBAC catalyzes linear ubiquitination of the kinetochore motor CENP-E, which is specifically required for the localization of CENP-E at attached kinetochores, but not unattached ones. KNL1 acts as a receptor of linear ubiquitin chains to anchor CENP-E at attached kinetochores in prometaphase and metaphase. Thus, linear ubiquitination promotes chromosome congression and dynamic chromosome alignment by coupling the dynamic kinetochore microtubule receptor CENP-E to the static one, the KMN network.
Computationally efficient design of directionally compliant metamaterials
Authors: Shaw Lucas A. , Sun Frederick , Portela Carlos M. , Barranco Rodolfo I. , Greer Julia R. , Hopkins Jonathan B.
Published: January 2019

Designing mechanical metamaterials is overwhelming for most computational approaches because of the staggering number and complexity of flexible elements that constitute their architecture—particularly if these elements don’t repeat in periodic patterns or collectively occupy irregular bulk shapes. We introduce an approach, inspired by the freedom and constraint topologies (FACT) methodology, that leverages simplified assumptions to enable the design of such materials with ~6 orders of magnitude greater computational efficiency than other approaches (e.g., topology optimization). Metamaterials designed using this approach are called directionally compliant metamaterials (DCMs) because they manifest prescribed compliant directions while possessing high stiffness in all other directions. Since their compliant directions are governed by both macroscale shape and microscale architecture, DCMs can be engineered with the necessary design freedom to facilitate arbitrary form and unprecedented anisotropy. Thus, DCMs show promise as irregularly shaped flexure bearings, compliant prosthetics, morphing structures, and soft robots.
Publisher Correction: Novel pleiotropic risk loci for melanoma and nevus density implicate multiple biological pathways
Authors: Duffy David L. , Zhu Gu , Li Xin , Sanna Marianna , Iles Mark M. , Jacobs Leonie C. , Evans David M. , Yazar Seyhan , Beesley Jonathan , Law Matthew H. , Kraft Peter , Visconti Alessia , Taylor John C. , Liu Fan , Wright Margaret J. , Henders Anjali K. , Bowdler Lisa , Glass Dan , Ikram M. Arfan , Uitterlinden André G. , Madden Pamela A. , Heath Andrew C. , Nelson Elliot C. , Green Adele C. , Chanock Stephen , Barrett Jennifer H. , Brown Matthew A. , Hayward Nicholas K. , MacGregor Stuart , Sturm Richard A. , Hewitt Alex W. ,   Melanoma GWAS Consortium, Lee Jeffrey E. , Brossard Myriam , Moses Eric K. , Song Fengju , Kumar Rajiv , Easton Douglas F. , Pharoah Paul D. P. , Swerdlow Anthony J. , Kypreou Katerina P. , Harland Mark , Randerson-Moor Juliette , Akslen Lars A. , Andresen Per A. , Avril Marie-Françoise , Azizi Esther , Scarrà Giovanna Bianchi , Brown Kevin M. , Dębniak Tadeusz , Elder David E. , Fang Shenying , Friedman Eitan , Galan Pilar , Ghiorzo Paola , Gillanders Elizabeth M. , Goldstein Alisa M. , Gruis Nelleke A. , Hansson Johan , Helsing Per , Hočevar Marko , Höiom Veronica , Ingvar Christian , Kanetsky Peter A. , Chen Wei V. , Landi Maria Teresa , Lang Julie , Lathrop G. Mark , Lubiński Jan , Mackie Rona M. , Mann Graham J. , Molven Anders , Novaković Srdjan , Olsson Håkan , Puig Susana , Puig-Butille Joan Anton , Radford-Smith Graham L. , van der Stoep Nienke , van Doorn Remco , Whiteman David C. , Craig Jamie E. , Schadendorf Dirk , Simms Lisa A. , Burdon Kathryn P. , Nyholt Dale R. , Pooley Karen A. , Orr Nicholas , Stratigos Alexander J. , Cust Anne E. , Ward Sarah V. , Schulze Hans-Joachim , Dunning Alison M. , Demenais Florence , Amos Christopher I. , Kayser Manfred , Hunter David J. , Newton Bishop Julia A. , Spector Timothy D. , Montgomery Grant W. , Mackey David A. , Smith George Davey , Nijsten Tamar E. , Bishop D. Timothy , Bataille Veronique , Falchi Mario , Han Jiali , Martin Nicholas G.
Published: January 2019

The original version of this Article contained errors in the spelling of the authors Fan Liu and M. Arfan Ikram, which were incorrectly given as Fan Lui and Arfan M. Ikram. In addition, the original version of this Article also contained errors in the author affiliations which are detailed in the associated Publisher Correction.
Prefrontal mechanisms combining rewards and beliefs in human decision-making
Authors: Rouault Marion , Drugowitsch Jan , Koechlin Etienne
Published: January 2019

In uncertain and changing environments, optimal decision-making requires integrating reward expectations with probabilistic beliefs about reward contingencies. Little is known, however, about how the prefrontal cortex (PFC), which subserves decision-making, combines these quantities. Here, using computational modelling and neuroimaging, we show that the ventromedial PFC encodes both reward expectations and proper beliefs about reward contingencies, while the dorsomedial PFC combines these quantities and guides choices that are at variance with those predicted by optimal decision theory: instead of integrating reward expectations with beliefs, the dorsomedial PFC built context-dependent reward expectations commensurable to beliefs and used these quantities as two concurrent appetitive components, driving choices. This neural mechanism accounts for well-known risk aversion effects in human decision-making. The results reveal that the irrationality of human choices commonly theorized as deriving from optimal computations over false beliefs, actually stems from suboptimal neural heuristics over rational beliefs about reward contingencies.