bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Interplay of the Solar Wind Core and Suprathermal Electrons: A Quasilinear Approach for Firehose Instability
Authors: Shaaban S. M. , Lazar M. , Yoon P. H. , Poedts S. 
Published: February 2019

Abstract
In the solar wind an equipartition of kinetic energy densities can be easily established between thermal and suprathermal electrons and the instability conditions are markedly altered by the interplay of these two populations. The new thresholds derived here for the periodic branch of firehose instability shape the limits of temperature anisotropy reported by observations for both electron populations. This instability constraint is particularly important for suprathermal electrons which, by comparison with thermal populations, are even less controlled by particle–particle collisions. An extended quasilinear approach to this instability confirms predictions from linear theory and unveils the mutual effects of thermal and suprathermal electrons in the relaxation of their temperature anisotropies and the saturation of growing fluctuations.
Predicting the Extreme Ultraviolet Radiation Environment of Exoplanets around Low-mass Stars: The TRAPPIST-1 System
Authors: Peacock Sarah , Barman Travis , Shkolnik Evgenya L. , Hauschildt Peter H. , Baron E. 
Published: February 2019

Abstract
The high energy radiation environment around M dwarf stars strongly impacts the characteristics of close-in exoplanet atmospheres, but these wavelengths are difficult to observe due to geocoronal and interstellar contamination. On account of these observational restrictions, a stellar atmosphere model may be used to compute the stellar extreme ultraviolet (EUV; 100–912 Å) spectrum. We construct semiempirical nonlocal thermodynamic equilibrium model spectra of the ultracool M8 star TRAPPIST-1 that span EUV to infrared wavelengths (100 Å−2.5 μm) using the atmosphere code PHOENIX. These upper atmosphere models contain prescriptions for the chromosphere and transition region and include newly added partial frequency redistribution capabilities. In the absence of broadband UV spectral observations, we constrain our models using Hubble Space Telescope Lyman α observations from TRAPPIST-1 and Galaxy Evolution Explorer UV photometric detections from a set of old M8 stars (>1 Gyr). We find that calibrating the models using both data sets separately yield similar far-ultraviolet and NUV fluxes, and EUV fluxes that range from (1.32–17.4) × 10−14 ergs s−1 cm−2. The results from these models demonstrate that the EUV emission is very sensitive to the temperature structure in the transition region. Our lower activity models predict EUV fluxes similar to previously published estimates derived from semiempirical scaling relationships, while the highest activity model predicts EUV fluxes a factor of 10 higher. Results from this study support the idea that the TRAPPIST-1 habitable zone planets likely do not have much liquid water on their surfaces due to the elevated levels of high energy radiation emitted by the host star.
A New MHD Model with a Rotated-hybrid Scheme and Solenoidality-preserving Approach
Authors: Feng Xueshang , Liu XiaoJing , Xiang Changqing , Li HuiChao , Wei Fengsi 
Published: February 2019

Abstract
In this paper, the rotated-hybrid scheme is applied for the first time to 3D magnetohydrodynamics (MHD) equations in the finite-volume frame. This scheme is devised by decomposing a cell-face normal vector into two orthogonal directions and combining the Roe solver, a full-wave or complete Riemann solver, and the Rusanov solver, an incomplete Riemann solver, into one rotated-hybrid Riemann solver. To keep the magnetic field divergence-free, we propose two kinds of divergence-cleaning approaches by combining the least-squares reconstruction of magnetic field with the divergence-free constraints. One is the locally solenoidality-preserving method designed to locally maintain the magnetic solenoidality exactly, not just in a least-squares sense, and another is the globally solenoidality-preserving (SP) approach that is implemented by adding a global constraint but abandons the exactness of the locally divergence-free condition. Both SP methods are employed for 3D MHD with a rotated-hybrid scheme in the finite-volume frame. To validate and demonstrate the capabilities of the rotated-hybrid scheme for MHD, we perform an Orszag–Tang MHD vortex problem and a numerical study for the steady-state coronal structures of Carrington rotation 2068 during the solar activity minimum. The numerical tests show the robustness of the proposed scheme and demonstrate the capability of these two SP approaches to keep the magnetic divergence errors to the expected accuracy.
Determination of the Total Accelerated Electron Rate and Power Using Solar Flare Hard X-Ray Spectra
Authors: Kontar Eduard P. , Jeffrey Natasha L. S. , Emslie A. Gordon 
Published: February 2019

Abstract
Solar flare hard X-ray (HXR) spectroscopy serves as a key diagnostic of the accelerated electron spectrum. However, the standard approach using the collisional cold thick-target model poorly constrains the lower-energy part of the accelerated electron spectrum, hence the overall energetics of the accelerated electrons are typically constrained only to within one or two orders of magnitude. Here, we develop and apply a physically self-consistent, warm-target approach that involves the use of both HXR spectroscopy and imaging data. This approach allows an accurate determination of the electron distribution low-energy cutoff, and hence the electron acceleration rate and the contribution of accelerated electrons to the total energy released, by constraining the coronal plasma parameters. Using a solar flare observed in X-rays by RHESSI, we demonstrate that using the standard cold-target methodology, the low-energy cutoff (hence the energy content in electrons) is essentially undetermined. However, the warm-target methodology can determine the low-energy electron cutoff with ∼7% uncertainty at the 3σ level, hence it permits an accurate quantitative study of the importance of accelerated electrons in solar flare energetics.
Effects of the Isothermal Region in Protoplanetary Disks and the Protostar Irradiation on the Disk Instability Model for Giant Planet Formation
Authors: Tang Pengfei , Jin Liping 
Published: February 2019

Abstract
We construct an analytical model of gravitationally unstable protoplanetary disks consisting of three regions: the inner region where the internal dissipation dominates the heating, the intermediate region where the central protostar irradiation dominates, and the outer region where background irradiation dominates. We use this analytical model and an evolutionary numerical model of protoplanetary disks to calculate the cooling time and find out the location of the isothermal region. We investigate the effects of the isothermal region on the disk instability model for giant planet formation. We find that the fragmentation region found in previous studies is contained in the isothermal region of a disk. In this case, the cooling time criterion is not applicable for fragmentation. Therefore, the constraint on the disk instability model caused by the cooling time criterion should be relieved. The viability of the disk instability model is improved. When the isothermal region is considered, the inner boundary of the fragmentation region is extended inward to ∼20 au. We also show that if the contribution of the protostar irradiation to the disk surface temperature can be included in the cooling rate, the fragmentation region defined by the cooling time criterion can be extended inward to ∼26 au. We find that a disk tends to be isothermal in the region where the cooling time criterion is satisfied. We also find that at the later stage of disk instability, the inner boundary of the fragmentation region is determined by the inner boundary of the gravitationally unstable region.
DEVELOPING A RESILIENCE TOOL FOR HIGHER EDUCATION INSTITUTIONS: A MUST-HAVE IN CAMPUS MASTER PLANNING
Authors: Storms Keith , Simundza Dan , Morgan Elizabeth , Miller Scott 
Published: February 2019

INTRODUCTION Resilience has become a prominent topic in the planning and design industry over the past several years. States, cities and entire regions face an ever-growing threat of environmental and societal challenges, including natural disasters, sea level rise, climate change, terrorism and financial insolvency. Around the world, universities are leading efforts in terms of research and problem solving regarding resilience and sustainability in their broader communities. As campus planners working nationwide with higher education clients, we see an increasing opportunity for higher education researchers, leaders and institutions to bring this same leadership stance to addressing their campus' own resilience. A campus master plan is perhaps the pinnacle opportunity to connect expert researchers with campus stewards and community leaders to engage in dialogue, identify priorities and advance resilience within their campus and community. A comprehensive master plan, by its very nature, will guide and protect an institution's long-range survival and plans. Such long-range planning is now more critical than ever given the deep financial pressures and flat or declining demographics that so many institutions face. Being proactive versus reactive increases the likelihood that institutions will succeed and continue to meet the needs of students and communities. Universities should continue or begin to address resilience challenges and opportunities in whatever scope possible. This paper will give university leaders and industry participants a broad framework to direct discussion and dissect levels of resilience, opportunities and potential shortfalls, and highlight resilient campus planning best practices. The aim is to provide a framework for institutions to measure and strengthen the resilience of their infrastructure, culture, and systems, while contributing to the resilience of their communities.
The dust-jacket considered
Authors: Smith Margit J 
Published: February 2019

This article addresses the history of protective book coverings from earliest times to their current use; their design as it mirrors changes in the graphic arts and materials over the past century; scholarly, commercial, and marketing use of dust-jackets, collections in institutions. Treatment in library settings and availability to students and users will also be discussed. Findings, suggestions and instructions for their preservation, pros and cons of retention, importance in the rare book trade, and the production of fake and facsimile dust-jackets are also considered.
Lost in Reintegration?
Authors: Grenda Magdalena 
Published: February 2019

This article describes different approaches to the issue of image reintegration and filling in the areas of loss in photographs and photographic postcards. The approach varies depending on the context of the photographs’ usage, the owner’s expectations and the will of the photographer. The paper discusses treatments of various photographic artifacts and presents the complexity of conservation problems associated with photographic objects. The diversity of solutions and decisions proves that there are numerous factors to consider and that there are no simple answers when it comes to decision making.
Efficacy of Chemokine Receptor Inhibition in Treating IL-36α–Induced Psoriasiform Inflammation
Authors: Campbell James J. , Ebsworth Karen , Ertl Linda S. , McMahon Jeffrey P. , Wang Yu , Yau Simon , Mali Venkat R. , Chhina Vicky , Kumamoto Alice , Liu Shirley , Dang Ton , Newland Dale , Charo Israel F. , Zhang Penglie , Schall Thomas J. , Singh Rajinder 
Published: February 2019

Abstract
Several types of psoriasiform dermatitis are associated with increased IL-36 cytokine activity in the skin. A rare, but severe, psoriasis-like disorder, generalized pustular psoriasis (GPP), is linked to loss-of-function mutations in the gene encoding IL-36RA, an important negative regulator of IL-36 signaling. To understand the effects of IL-36 dysregulation in a mouse model, we studied skin inflammation induced by intradermal injections of preactivated IL-36α. We found the immune cells infiltrating IL-36α–injected mouse skin to be of dramatically different composition than those infiltrating imiquimod-treated skin. The IL-36α–induced leukocyte population comprised nearly equal numbers of CD4+ αβ T cells, neutrophils, and inflammatory dendritic cells, whereas the imiquimod-induced population comprised γδ T cells and neutrophils. Ligands for chemokine receptors CCR6 and CXCR2 are increased in both GPP and IL-36α–treated skin, which led us to test an optimized small-molecule antagonist (CCX624) targeting CCR6 and CXCR2 in the IL-36α model. CCX624 significantly reduced the T cell, neutrophil, and inflammatory dendritic cell infiltrates and was more effective than saturating levels of an anti–IL-17RA mAb at reducing inflammatory symptoms. These findings put CCR6 and CXCR2 forward as novel targets for a mechanistically distinct therapeutic approach for inflammatory skin diseases involving dysregulated IL-36 signaling, such as GPP.
Impact of humidity biases on light precipitation occurrence: observations versus simulations
Authors: Bastin Sophie , Drobinski Philippe , Chiriaco Marjolaine , Bock Olivier , Roehrig Romain , Gallardo Clemente , Conte Dario , Domínguez Alonso Marta , Li Laurent , Lionello Piero , Parracho Ana C. 
Published: February 2019

Abstract. This work uses a network of GPS stations over Europe from which a homogenized
integrated water vapor (IWV) dataset has been retrieved, completed with
colocated temperature and precipitation measurements over specific stations
to (i) estimate the biases of six regional climate models over Europe in terms
of humidity; (ii) understand their origins; and (iii) finally assess the impact
of these biases on the frequency of occurrence of precipitation. The
evaluated simulations have been performed in the framework of
HYMEX/Med-CORDEX programs and cover the Mediterranean area and part of Europe
at horizontal resolutions of 50 to 12 km. The analysis shows that models tend to overestimate the low values of IWV
and the use of the nudging technique reduces the differences between GPS and
simulated IWV. Results suggest that physics of models mostly explain the
mean biases, while dynamics affects the variability. The land
surface–atmosphere exchanges affect the estimation of IWV over most part of
Europe, especially in summer. The limitations of the models to represent
these processes explain part of their biases in IWV. However, models
correctly simulate the dependance between IWV and temperature, and
specifically the deviation that this relationship experiences regarding the
Clausius–Clapeyron law after a critical value of temperature (Tbreak).
The high spatial variability of Tbreak indicates that it has a strong
dependence on local processes which drive the local humidity sources. This
explains why the maximum values of IWV are not necessarily observed over
warmer areas, which are often dry areas. Finally, it is shown over the SIRTA observatory (near Paris) that the frequency
of occurrence of light precipitation is strongly conditioned by the biases
in IWV and by the precision of the models to reproduce the distribution of
IWV as a function of the temperature. The results of the models indicate
that a similar dependence occurs in other areas of Europe, especially where
precipitation has a predominantly convective character. According to the
observations, for each range of temperature, there is a critical value of
IWV from which precipitation starts to increase. The critical values and the
probability of exceeding them are simulated with a bias that depends on the
model. Those models, which generally present light precipitation too often,
show lower critical values and higher probability of exceeding them.
NWP-based lightning prediction using flexible count data regression
Authors: Simon Thorsten , Mayr Georg J. , Umlauf Nikolaus , Zeileis Achim 
Published: February 2019

Abstract. A method to predict lightning by postprocessing numerical weather prediction
(NWP) output is developed for the region of the European Eastern Alps.
Cloud-to-ground (CG) flashes – detected by the ground-based Austrian
Lightning Detection &amp; Information System (ALDIS) network – are counted on
the 18×18 km2 grid of the 51-member NWP ensemble of the European
Centre for Medium-Range Weather Forecasts (ECMWF). These counts serve as the
target quantity in count data regression models for the occurrence of
lightning events and flash counts of CG. The probability of lightning
occurrence is modelled by a Bernoulli distribution. The flash counts are
modelled with a hurdle approach where the Bernoulli distribution is combined
with a zero-truncated negative binomial. In the statistical models the
parameters of the distributions are described by additive predictors, which
are assembled using potentially nonlinear functions of NWP covariates.
Measures of location and spread of 100 direct and derived NWP covariates
provide a pool of candidates for the nonlinear terms. A combination of
stability selection and gradient boosting identifies the nine (three) most
influential terms for the parameters of the Bernoulli (zero-truncated
negative binomial) distribution, most of which turn out to be associated with
either convective available potential energy (CAPE) or convective
precipitation. Markov chain Monte Carlo (MCMC) sampling estimates the final
model to provide credible inference of effects, scores, and
predictions. The selection of terms and MCMC sampling are applied for data of
the year 2016, and out-of-sample performance is evaluated for 2017. The
occurrence model outperforms a reference climatology – based on 7 years of
data – up to a forecast horizon of 5 days. The flash count model is
calibrated and also outperforms climatology for exceedance probabilities,
quantiles, and full predictive distributions.
Systematic identification of external influences in multi-year microseismic recordings using convolutional neural networks
Authors: Meyer Matthias , Weber Samuel , Beutel Jan , Thiele Lothar 
Published: February 2019

Abstract. Passive monitoring of ground motion can be used for geophysical process
analysis and natural hazard assessment. Detecting events in microseismic
signals can provide responsive insights into active geophysical processes.
However, in the raw signals, microseismic events are superimposed by external
influences, for example, anthropogenic or natural noise sources that distort
analysis results. In order to be able to perform event-based geophysical
analysis with such microseismic data records, it is imperative that negative
influence factors can be systematically and efficiently identified,
quantified and taken into account. Current identification methods (manual and
automatic) are subject to variable quality, inconsistencies or human errors.
Moreover, manual methods suffer from their inability to scale to increasing
data volumes, an important property when dealing with very large data volumes
as in the case of long-term monitoring. In this work, we present a systematic strategy to identify a multitude of
external influence sources, characterize and quantify their impact and
develop methods for automated identification in microseismic signals. We
apply the strategy developed to a real-world, multi-sensor, multi-year
microseismic monitoring experiment performed at the Matterhorn Hörnligrat
(Switzerland). We develop and present an approach based on convolutional
neural networks for microseismic data to detect external influences
originating in mountaineers, a major unwanted influence, with an error rate
of less than 1 %, 3 times lower than comparable algorithms. Moreover, we
present an ensemble classifier for the same task, obtaining an error rate of
0.79 % and an F1 score of 0.9383 by jointly using time-lapse image and
microseismic data on an annotated
subset of the monitoring data. Applying these classifiers to the whole
experimental dataset reveals that approximately one-fourth of events detected
by an event detector without such a preprocessing step are not due to seismic
activity but due to anthropogenic influences and that time periods with
mountaineer activity have a 9 times higher event rate. Due to these findings,
we argue that a systematic identification of external influences using a
semi-automated approach and machine learning techniques as presented in this
paper is a prerequisite for the qualitative and quantitative analysis of
long-term monitoring experiments.
"Timbeando en Nueva York": Cuban Timba Takes Root Abroad
Authors: Town Sarah 
Published: February 2019

Abstract
Timba came of age during Cuba’s 1990s economic crisis and soon traveled farther afield. In New York City today, diverse musicians reproduce, experiment with, and transform its sound with cover songs, new compositions, and reconfigured formats. This article examines three musical examples in ethnographic context, revealing tensions and overlap between local and cosmopolitan music practices, and sheds light on a popular dance culture that serves as the meeting ground for oral traditions and conservatory training. Through grounded and detailed investigation, it highlights blurred boundaries between musical practices, social spaces, and disciplinary approaches and explores their methodological and narrative implications.
Teorias da linguagem e estudos do discurso: apontamentos metodológicos para uma análise do discurso religioso
Authors: Terra Kenner Roger Cazotto 
Published: February 2019

Sob o paradigma da Modernidade acreditava-se na referencialidade direta entre conceito e mundo, signos e realidade. Com os novos estudos linguísticos, a fissura e descontinuidade entre coisa e palavra revelaram a limitação das metanarrativas e suas derivações. A consequência natural desse horizonte foi uma verdadeira virada nas ciências humanas. A linguagem percebeu-se como significação e não reflexo direto das coisas a respeito das quais se pronuncia. Para os estudos da religião, essas renovadas perspectivas das teorias da linguagem serviram de mudança paradigmática, produzindo uma verdadeira explosão metodológica. Por isso, ferramentas habilidosas para os estudos da linguagem tem ganhado espaço nos estudos da religião, possibilitando compreendê-la como lócus de sentidos. Dessa forma, as múltiplas linguagens da religião, por vezes tratadas como distorção do real ou ideologia alienante, são acessadas como sistema complexo de narrativas, símbolos, ritos, artes e performances aptas para a criação e compreensão do mundo. A partir dessa preocupação, estabelecem-se as pesquisas das Linguagens da Religião cujos aportes teóricos e objetos avançam à produção simbólica da religião. Dentro dessa discussão metodológica, preocupada em compreender e interpretar as linguagens produzidas pela religião, o artigo pretende apresentar a Análise do Discurso traduzida para os estudos da religião e suas contribuições metodológicas aos estudos do discurso religioso. O texto apresentará, na primeira parte, os principais aportes teóricos da Análise do Discurso francesa. Essa tarefa apontará algumas intuições e provocações possibilitando uma Análise do Discurso Religioso.