bluuebunny/crossref_metadata_2025 huggingface dataset:
Revisiting Global Welfare Regime Classifications
Authors: Roumpakis Antonios
Published: September 2020

This review article revisits the influential work of Gough (2004a, 2004b) on global welfare regimes fifteen years later. The article attempts to explore how far this literature has managed to pave a bridge between comparative social policy and development studies and explores the key contributions it offered in explaining welfare regime classification in Asia, Africa and Latin America. The article then reviews selected publications that have incorporated or applied Gough’s approach and in particular reviews how far scholars developed, complemented and questioned Gough’s approach. The review focuses on the causal properties for capturing the diversity of welfare regime classifications, empirical data, methodologies applied to classify welfare regimes, cases selected, groupings identified and finally how transitions to different welfare regime memberships are explained. In the conclusion, the article discusses findings and implications for global welfare regime classification debates.
Confronting the Indian State: Islamism, secularism, and the Kashmiri Muslim question
Authors: Majid Iymon
Published: September 2020

This paper investigates the framework of Islamist politics of Jama'at e Islami in Indian-administered Kashmir. Even though Jama'at e Islami creates the notion of “other” in the Indian state and challenges it but Kashmir's provincial relationship with India also forces it to work within the limits set up by the same state. This paper, thus, conceptualizes the relationship between Indian state and Islamists in a Muslim Majority region that demands the right to self-determination. In doing so, the paper interrogates Jama'at e Islami's rhetorical opposition to the political doctrine of Indian secularism and raises queries about minority rights and their place in the Islamist project.
On the properties of the magnetic Chemically Peculiar B, A, and F-type stars
Authors: Yüce Kutluay , Adelman Saul J. , Pyper Diane M. , Dukes Robert J.
Published: September 2020

We present a preliminary analysis of the Strömgren uvby photometry of the magnetic CP stars obtained using the Four College Automated Photometric Telescope for its 21.5 years of operation ending in Fall 2012. We summarize the photometry for all the FCAPT mCP stars that have been published to date. We do not find any significant correlation between the amplitudes of variation in the uvby filters and the periods. A small number of stars show anomalous behaviour of the v filter which will be discussed in a future study.
Magnetic field and prominences of the young, solar-like, ultra-rapid rotator AP 149
Authors: Cang Tianqi , Petit Pascal , Folsom Colin , Donati Jean-Francois
Published: September 2020

Young solar analogs reaching the main sequence experience very strong magnetic activity, directly linked to their angular momentum loss through wind and mass ejections. We investigate here the surface and chromospheric activity of the ultra-rapid rotator AP 149 in the young open cluster alpha Persei. With a time-series of spectropolarimetric observations gathered over two nights with ESPaDOnS, we are able to reconstruct the surface distribution of brightness and magnetic field using the Zeeman-Doppler-Imaging (ZDI) method. Using the same data set, we also map the spatial distribution of prominences through tomography of H-alpha emission. We find that AP 149 shows a strong cool spot and magnetic field closed to the polar cap. This star is the first example of a solar-type star to have its magnetic field and prominences mapped together, which will help to explore the respective role of wind and prominences in the angular momentum evolution of the most active stars.
Observing the Sun with the Atacama Large Millimeter/submillimeter Array – from continuum to magnetic fields
Authors: Wedemeyer Sven , Szydlarski Mikolaj , Rodriguez Jaime de la Cruz , Jafarzadeh Shahin
Published: September 2020

The Atacama Large Millimeter/submillimeter Array offers regular observations of our Sun since 2016. After an extended period of further developing and optimizing the post-processing procedures, first scientific results are now produced. While the first observing cycles mostly provided mosaics and time series of continuum brightness temperature maps with a cadence of 1-2s, additional receiver bands and polarization capabilities will be offered in the future. Currently, polarization capabilities are offered for selected receiver bands but not yet for solar observing. An overview of the recent development, first scientific results and potential of solar magnetic field measurements with ALMA will be presented.
Fast downflows in a chromospheric filament
Authors: Sowmya K. , Lagg A. , Solanki S. K. , Castellanos Durán J. S.
Published: September 2020

An active region filament in the upper chromosphere is studied using spectropolarimetric data in He i 10830 Å from the GREGOR telescope. A Milne-Eddingon based inversion of the Unno-Rachkovsky equations is used to retrieve the velocity and the magnetic field vector of the region. The plasma velocity reaches supersonic values closer to the feet of the filament barbs and coexist with a slow velocity component. Such supersonic velocities result from the acceleration of the plasma as it drains from the filament spine through the barbs. The line-of-sight magnetic fields have strengths below 200 G in the filament spine and in the filament barbs where fast downflows are located, their strengths range between 100 - 700 G.
Analysis of the chromosphere and corona of low-activity early-M dwarfs
Authors: Scandariato Gaetano , Álvarez E. González , Maldonado J. , Mascareño A. Suárez ,   the HADES collaboration
Published: September 2020

While most of the exoplanets have been found orbiting around solar-type stars, low-mass stars have recently been recognized as ideal exo-life laboratory. Currently, stellar activity is one of the limiting factors for the characterization of Earth-twins and for assessing their habitability: understanding the activity of M dwarfs is thus crucial. In this contribution I present the spectroscopic analysis of the quiet early-M dwarfs monitored within the HADES (HArps-n red Dwarf Exoplanet Survey) radial velocity survey. The spectra allow us to analyze simultaneously the Ca ii H&K doublet and the Hydrogen Balmer series, while the intensive follow up gives us a large number of spectra ( 100) for each target. We complement this dataset with ground-based follow-up photometry and archival X-ray data. I present our results on the activity-rotation-stellar parameters and flux-flux relationships, and discuss the correlation of emission fluxes at low activity levels and the evolution timescales of active regions.
The magnetic structure and dynamics of a decaying active region
Authors: Kontogiannis Ioannis , Kuckein Christoph , González Manrique Sergio Javier , Felipe Tobias , Verma Meetu , Balthasar Horst , Denker Carsten
Published: September 2020

We study the evolution of the decaying active region NOAA 12708, from the photosphere up to the corona using high resolution, multi-wavelength GREGOR observations taken on May 9, 2018. We utilize spectropolarimetric scans of the 10830 Å spectral range by the GREGOR Infrared Spectrograph (GRIS), spectral imaging time-series in the Na ID2 spectral line by the GREGOR Fabry-Pérot Interferometer (GFPI) and context imaging in the Ca IIH and blue continuum by the High-resolution Fast Imager (HiFI). Context imaging in the UV/EUV from the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO) complements our dataset. The region under study contains one pore with a light-bridge, a few micro-pores and extended clusters of magnetic bright points. We study the magnetic structure from the photosphere up to the upper chromosphere through the spectropolarimetric observations in He II and Si I and through the magnetograms provided by the Helioseismic and Magnetic Imager (HMI). The high-resolution photospheric images reveal the complex interaction between granular-scale convective motions and a range of scales of magnetic field concentrations in unprecedented detail. The pore itself shows a strong interaction with the convective motions, which eventually leads to its decay, while, under the influence of the photospheric flow field, micro-pores appear and disappear. Compressible waves are generated, which are guided towards the upper atmosphere along the magnetic field lines of the various magnetic structures within the field-of-view. Modelling of the He i absorption profiles reveals high velocity components, mostly associated with magnetic bright points at the periphery of the active region, many of which correspond to asymmetric Si I Stokes-V profiles revealing a coupling between upper photospheric and upper chromospheric dynamics. Time-series of Na ID2 spectral images reveal episodic high velocity components at the same locations. State-of-the-art multi-wavelength GREGOR observations allow us to track and understand the mechanisms at work during the decay phase of the active region.
Multi-flux-rope system in solar active regions
Authors: Hou Yijun , Zhang Jun , Li Ting , Yang Shuhong
Published: September 2020

Magnetic flux rope (MFR) is closely connected with solar eruptions, such as flares and coronal mass ejections. The classical scenario assumes a single MFR for each eruption, but it is reasonable to expect multiple MFRs in a complex active region (AR). Statistically investigating AR 11897, we verify the existence of multiple MFR proxies during the AR evolution. Recently, AR 12673 in 2017 September produced the two largest flares in Solar Cycle 24. The evolutions of the AR magnetic fields and the two large flares reveal that significant flux emergence and successive interactions between different emerging dipoles resulted in the formations of multiple MFRs and twisted loop bundles, which successively erupted like a chain reaction within several minutes before the peaks of the two flares. We propose that the eruptions of a multi-flux-rope system can rapidly release enormous magnetic energy and result in large flares in solar AR.
The impact of magnetism on tidal dynamics in the convective envelope of low-mass stars
Authors: Astoul A. , Mathis S. , Baruteau C. , Gallet F. , Strugarek A. , Augustson K. C. , Brun A. S. , Bolmont E.
Published: September 2020

For the shortest period exoplanets, star-planet tidal interactions are likely to have played a major role in the ultimate orbital evolution of the planets and on the spin evolution of the host stars. Although low-mass stars are magnetically active objects, the question of how the star’s magnetic field impacts the excitation, propagation and dissipation of tidal waves remains open. We have derived the magnetic contribution to the tidal interaction and estimated its amplitude throughout the structural and rotational evolution of low-mass stars (from K to F-type). We find that the star’s magnetic field has little influence on the excitation of tidal waves in nearly circular and coplanar Hot-Jupiter systems, but that it has a major impact on the way waves are dissipated.
The 3D structure of the penumbra at high resolution from the bottom of the photosphere to the middle chromosphere
Authors: Murabito Mariarita , Ermolli Ilaria , Giorgi Fabrizio , Stangalini Marco , Guglielmino Salvo L. , Jafarzadeh Shahin , Socas-Navarro Hector , Romano Paolo , Zuccarello Francesca
Published: September 2020

Sunspots are the most prominent feature of the solar magnetism in the photosphere. Although they have been widely investigated in the past, their structure remains poorly understood. Indeed, due to limitations in observations and the complexity of the magnetic field estimation at chromospheric heights, the magnetic field structure of sunspot above the photosphere is still uncertain. Improving the present knowledge of sunspot is important in solar and stellar physics, since spot generation is seen not only on the Sun, but also on other solar-type stars. In this regard, we studied a large, isolated sunspot with spectro-polarimeteric measurements that were acquired at the Fe I 6173 nm and Ca II 8542 nm lines by the spectropolarimeter IBIS/DST under excellent seeing conditions lasting more than three hours. Using the Non-LTE inversion code NICOLE, we inverted both line measurements simultaneously, to retrieve the three-dimensional magnetic and thermal structure of the penumbral region from the bottom of the photosphere to the middle chromosphere. Our analysis of data acquired at spectral ranges unexplored in previous studies shows clear spine and intra-spine structure of the penumbral magnetic field at chromopheric heights. Our investigation of the magnetic field gradient in the penumbra along the vertical and azimuthal directions confirms results reported in the literature from analysis of data taken at the spectral region of the He I 1083 nm triplet.
Ca II 854.2 nm spectropolarimetry compared with ALMA and with scattering polarization theory
Authors: Harvey J. W. ,   SOLIS Team
Published: September 2020

Ca II 854.2 nm spectropolarimetric observations of the Sun are compared with nearly simultaneous ALMA observations. These two types of chromospheric observations show rough agreement but also several notable differences. High-sensitivity (≃ 0.01%) observations reveal ubiquitous linear polarization structures across the solar disk in the core of the 854.2 nm line that are consistent with previous theoretical studies.
Reversibility of Turbulent and Non-Collisional Plasmas: Solar Wind
Authors: Acosta Belén , Pastén Denisse , Moya Pablo S.
Published: September 2020

We have studied turbulent plasma as a complex system applying the method known as Horizontal Visibility Graph (HVG) to obtain the Kullback-Leibler Divergence (KLD) as a first approach to characterize the reversibility of the time series of the magnetic fluctuations. For this, we have developed the method on Particle In Cell (PIC) simulations for a magnetized plasma and on solar wind magnetic time series, considering slow and fast wind. Our numerical results show that low irreversibility values are verified for magnetic field time series associated with Maxwellian distributions. In addition, considering the solar wind plasma, our preliminary results seem to indicate that greater irreversibility degrees are reached by the magnetic field associated with slow solar wind.
Diagnosing chromospheric magnetic field through simultaneous spectropolarimetry in Hα and Ca II 854.2 nm
Authors: Nagaraju K. , Sankarasubramanian K. , Rangarajan K. E.
Published: September 2020

Measurement of magnetic field in this layer is challenging both from point of view of observations and interpretation of the data. We present in this work about spectropolarimetric observations of a pore, simultaneously in Ca ii (CaIR) at 854.2 nm (CaIR) and H α (656.28 nm). The observed region includes a small scale energetic event (SSEE) taking place in the region between the pore and the region which show opposite polarity to that of pore at the photosphere. The energetic event appears to be a progressive reconnection event as shown by the time evolution of the intensity profiles. Closer examination of the intensity profiles from the downflow regions suggest that the height of formation of CaIR is higher than that of Hi α, contrary to the current understanding about their height of formation. Preliminary results on the inversion of Stokes-I and V profiles of CaIR are also presented.
Linking radio flares with spots on the active binary UX Arietis
Authors: Hummel Christian A. , Beasley Anthony
Published: September 2020

Signs of stellar activity such as large surface spots and radio flares are often related to binarity. UX Arietis is one of the most active members of the RS CVn class of binaries in which spin-up of a sub-giant/giant star by a close companion leads to the creation of magnetic fields. UX Arietis exhibits these signs of activity, originating mostly on the K0 sub-giant primary component. We measured the orbit with the CHARA interferometer and made images of a single large spot rotating in and out of view over a month in 2012. The rotation of the stars is synchronous with the orbit, and long-term photometric observations show that the spot or spots do not move much during intervals of a year. Our aim is to relate the positions of the stars and the spots on the primary to astrometry of the radio components observed during outbursts.
Coronal dimming as a proxy for stellar coronal mass ejections
Authors: Jin M. , Cheung M. C. M. , DeRosa M. L. , Nitta N. V. , Schrijver C. J. , France K. , Kowalski A. , Mason J. P. , Osten R.
Published: September 2020

Solar coronal dimmings have been observed extensively in the past two decades and are believed to have close association with coronal mass ejections (CMEs). Recent study found that coronal dimming is the only signature that could differentiate powerful flares that have CMEs from those that do not. Therefore, dimming might be one of the best candidates to observe the stellar CMEs on distant Sun-like stars. In this study, we investigate the possibility of using coronal dimming as a proxy to diagnose stellar CMEs. By simulating a realistic solar CME event and corresponding coronal dimming using a global magnetohydrodynamics model (AWSoM: Alfvén-wave Solar Model), we first demonstrate the capability of the model to reproduce solar observations. We then extend the model for simulating stellar CMEs by modifying the input magnetic flux density as well as the initial magnetic energy of the CME flux rope. Our result suggests that with improved instrument sensitivity, it is possible to detect the coronal dimming signals induced by the stellar CMEs.
Diagnosing coronal magnetic fields with radio imaging-spectroscopy technique
Authors: Yan Yihua , Tan Baolin , Melnikov V. , Chen Xingyao , Wang Wei , Chen Linjie , Liu Fei ,   MUSER Team
Published: September 2020

Mingantu Spectral Radioheliograph (MUSER) is an aperture-synthesis imaging telescope, dedicated to observe the Sun, operating on multiple frequencies in dm to cm range. The ability of MUSER to get images and measure Stokes I and V parameters simultaneously at many frequencies in a wide band is of fundamental importance. It allows one to approach/solve such important problems as measuring the strength, geometry and dynamics of magnetic field at coronal heights. Here we consider some of the recently developed radio physics methods to be used for solving the problems. These methods allow us to obtain information that is unattainable in other areas of the electromagnetic spectrum.
Statistical analysis of geomagnetic storms and their relation with the solar cycle
Authors: Reyes Paula , Pinto Victor A. , Moya Pablo S.
Published: September 2020

Geomagnetic storms can be modeled as stochastic processes with log-normal probability distribution function over their minimum Dst index value measured during the main phase of each event. Considering a time series of geomagnetic storm events between 1957 and 2019 we have analyzed the probability of occurrence of small, moderate, strong and extreme events. The data were separated according to solar cycle (SC) and solar cycle phases and fitted through maximum likelihood method in order to compare rates of occurrence of the last Solar Cycle (SC24) with previous ones. Our results show that for Dst < – 100 nT events in SC24 are similar to those in SC20, obtaining ⁓42 vs 21 median rate storms per cycle with 95% confidence intervals using Bootstrap Method. As SC24 has been the least active solar cycle in over 200 years, we conclude that this method tends to overestimate geomagnetic storms occurrence rates even for small events.
Diagnostics of non-thermal-distributions from solar flare EUV line spectra
Authors: Dzifčáková Elena , Zemanová Alena , Dudík Jaroslav , Lörinčík Juraj
Published: September 2020

Spectral line intensities observed by the Extreme Ultraviolet Variability Experiment (EVE) on board the Solar Dynamics Observatory (SDO) during 2012 March 9 M6.3 flare were used to diagnose a presence of a non-thermal electron distribution represented by a κ-distribution. The diagnosed electron densities ($\approx 2 \times {10^{11}}{\rm{c}}{{\rm{m}}^{ - 3}}$) are affected only a little by the presence of the non-thermal distribution, and are within the uncertainties of observation. On the other hand, the temperature diagnostics based on the line ratios involving different ionization degrees is strongly affected by the type of the electron distribution. The distribution functions diagnosed from relative Fe line intensities demonstrate the presence of strongly non-thermal distributions during the impulsive phase of the flare and later their gradual thermalization.
Early results from the solar-minimum 2019 total solar eclipse
Authors: Pasachoff Jay M. , Lockwood Christian A. , Inoue John L. , Meadors Erin N. , Voulgaris Aristeidis , Sliski David , Sliski Alan , Reardon Kevin P. , Seaton Daniel B. , Caplan Ronald M. , Downs Cooper , Linker Jon A. , Schneider Glenn , Rojo Patricio , Sterling Alphonse C.
Published: September 2020

We observed the 2 July 2019 total solar eclipse with a variety of imaging and spectroscopic instruments recording from three sites in mainland Chile: on the centerline at La Higuera, from the Cerro Tololo Inter-American Observatory, and from La Serena, as well as from a chartered flight at peak totality in mid-Pacific. Our spectroscopy monitored Fe X, Fe XIV, and Ar X lines, and we imaged Ar X with a Lyot filter adjusted from its original H-alpha bandpass. Our composite imaging has been compared with predictions based on modeling using magnetic-field measurements from the pre-eclipse month. Our time-differenced sites will be used to measure motions in coronal streamers.
Realistic 3D MHD modeling of self-organized magnetic structuring of the solar corona
Authors: Kitiashvili Irina N. , Wray Alan A. , Sadykov Viacheslav , Kosovichev Alexander G. , Mansour Nagi N.
Published: September 2020

The dynamics of solar magnetoconvection spans a wide range of spatial and temporal scales and extends from the interior to the corona. Using 3D radiative MHD simulations, we investigate the complex interactions that drive various phenomena observed on the solar surface, in the low atmosphere, and in the corona. We present results of our recent simulations of coronal dynamics driven by underlying magnetoconvection and atmospheric processes, using the 3D radiative MHD code StellarBox (Wray et al. 2018). In particular, we focus on the evolution of thermodynamic properties and energy exchange across the different layers from the solar interior to the corona.
A miniaturized tri-band bandpass microstrip filter using multiple resonators with sharp skirts
Authors: Wang Chenhao , Xi Xiaoli , Zhao Yuchen , Shi Xiaomin
Published: September 2020

In this paper, a miniaturized tri-band bandpass microstrip filter using stub loaded rectangular ring resonator (SLRRR)，shorted stub loaded stepped impedance resonators (SSLSIR), and stepped impedance resonators (SIR) with sharp skirts is presented. Two SSLSIRs are embedded paralleled inside SLRRR to generate a quasi-elliptic response at second and third passband. The odd-even fundamental resonant mode and first high-order resonant mode of the SIRs are exploited to generate tri-band response. Three bandwidths can be controlled independently due to different signal paths. Extra transmission zeros are introduced by the configuration of 0° feed structure. Sharp skirts are achieved at the upper edge of each passband by λg/4 lines which are loaded at the I/O ports. An example of the proposed tri-band filter operating at 2.76 GHz/5.7 GHz/7.63 GHz for TDD-LTE/WLAN/VSAT applications is implemented and fabricated. The simulation and measurement show a good agreement.
Introducing authentic materials alongside a reading-approach Latin course
Authors: Atkin Simon
Published: September 2020

The Department for Education (DfE) GCSE Subject Content for Ancient Languages embeds the study of literature as a significant requirement in the specifications of any Latin GCSE (DfE, 2018). Specifications are instructed to ‘require students to read a range of ancient literature, including at least one selection of prose and/or verse texts in the original language, adapted and abridged, as appropriate’ (DfE, 2018, p5). Furthermore, students are to be expected to respond to the literary style; show an understanding of the cultural and historical context; and compare and contrast ‘values and social practices from the ancient and modern worlds’ (DfE, 2018, p5). The two exam boards offering GCSE Latin, Oxford Cambridge and RSA (OCR) and Eduqas, take slightly different approaches to fulfilling these requirements. Both have a range of module options to choose from; however, OCR offers fewer choices of author in the original language (OCR, 2015), whereas Eduqas requires either six or ten different authors in its compulsory literature module (Eduqas, 2015).
Game-Informed Assessment for Playful Learning and Student Experience
Authors: Pavlou Maria
Published: September 2020

The educational value of play has long been acknowledged. During recent decades, much attention has been paid to video games and the multifarious ways in which they can promote and enhance learning. Μy main objective in this study is to weave game principles, learning and the notion of playfulness into assessment principles, in an attempt to investigate how what I call ‘Game-Informed Playful Assessment’ (GIPA) can affect student learning and particularly students’ experienceoflearning. The GIPA was designed with a view to promoting students’ agency, autonomy, collaboration and playfulness, and was introduced in an undergraduate course on Archaic Greek Lyric poetry at a Greek-speaking university. My data was generated through in-depth interviews with ten of the students that attended the course. While the GIPA was favourably and even enthusiastically received by students, the research also brought to the fore several other issues that call for attention, such as the stress that innovative assessment may provoke in students, and the readiness of students to be playful within an academic framework that typically contrasts serious work with playfulness and play in general.
Training Machine Learning Surrogate Models From a High‐Fidelity Physics‐Based Model: Application for Real‐Time Street‐Scale Flood Prediction in an Urban Coastal Community
Authors: Zahura Faria T. , Goodall Jonathan L. , Sadler Jeffrey M. , Shen Yawen , Morsy Mohamed M. , Behl Madhur
Published: September 2020

Mitigating the adverse impacts caused by increasing flood risks in urban coastal communities requires effective flood prediction for prompt action. Typically, physics‐based 1‐D pipe/2‐D overland flow models are used to simulate urban pluvial flooding. Because these models require significant computational resources and have long run times, they are often unsuitable for real‐time flood prediction at a street scale. This study explores the potential of a machine learning method, Random Forest (RF), to serve as a surrogate model for urban flood predictions. The surrogate model was trained to relate topographic and environmental features to hourly water depths simulated by a high‐resolution 1‐D/2‐D physics‐based model at 16,914 road segments in the coastal city of Norfolk, Virginia, USA. Two training scenarios for the RF model were explored: (i) training on only the most flood‐prone street segments in the study area and (ii) training on all 16,914 street segments in the study area. The RF model yielded high predictive skill, especially for the scenario when the model was trained on only the most flood‐prone streets. The results also showed that the surrogate model reduced the computational run time of the physics‐based model by a factor of 3,000, making real‐time decision support more feasible compared to using the full physics‐based model. We concluded that machine learning surrogate models strategically trained on high‐resolution and high‐fidelity physics‐based models have the potential to significantly advance the ability to support decision making in real‐time flood management within urban communities.
Exploring the Widespread Impacts of Ongoing Nitrogen Pollution
Authors: Katz Brian
Published: September 2020

The release of reactive nitrogen into the environment is having severe and ongoing ecosystem, economic, and human health impacts. How can we reduce our nitrogen footprint?
Global Whole Lithosphere Isostasy: Implications for Surface Elevations, Structure, Strength, and Densities of the Continental Lithosphere
Authors: Lamb Simon , Moore James D. P. , Perez‐Gussinye Marta , Stern Tim
Published: September 2020

The observed variations in the thickness of the conductive lithosphere, derived from surface wave studies, have a first‐order control on the elevation of the continents, in addition to variations in the thickness of the crust—this defines whole lithosphere isostasy (WLI). Negative buoyancy of the mantle lithosphere counters the positive buoyancy of the crust, and together, their respective thicknesses and density contrasts determine elevation of the continents both in their interiors and at their edges. The average density contrasts for lithospheric mantle with crust and with asthenosphere are typically 300 to 550 and 20 to 40 kg m−3, respectively, with a ratio 10 to 16, suggesting moderate average depletion of lithospheric mantle. We show that a crustal model for Antarctica, assuming WLI and using these density contrasts, provides a close fit to estimates of crustal thickness from surface wave tomography and gravity observations. We use a global model of WLI as a framework to assess factors controlling topography, showing that plausible regional variations in crustal and mantle densities, together with uncertainties in the crustal and conductive lithospheric thicknesses, are sufficient to account for global elevations without invoking dynamic topography greater than a few hundred meters. Estimates of elastic thickness Te in the continents are typically 25–50% of the thickness of the conductive lithosphere, indicating that the mantle part supports some of the elastic strength of the lithosphere.
Enhanced Densities in the Martian Thermosphere Associated With the 2018 Planet‐Encircling Dust Event: Results From MENCA/MOM and NGIMS/MAVEN
Authors: Venkateswara Rao N. , Gupta Neha , Kadhane Umesh R.
Published: September 2020

Response of the Martian upper thermosphere to the lower atmospheric dust activity is studied using unique observations made together by the Mars Orbiter Mission (MOM) and the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft. The Mars Exospheric Neutral Composition Analyzer (MENCA)/MOM and the Neutral Gas and Ion Mass Spectrometer (NGIMS)/MAVEN have simultaneously (on the same day) measured the neutral densities in the Martian thermosphere on 5, 8, 10, 13, 16, and 29 June 2018. The measurement period falls in the onset and progression time of the planet‐encircling dust event (PEDE) in the Mars lower atmosphere. During this time, the inbound trajectories of MAVEN and MOM spacecraft occurred on the dawnside and duskside, respectively. Using these observations, we found that thermospheric densities both on the dawnside and duskside are enhanced associated with the onset and growth of PEDE‐2018. The enhancement, however, is more on the duskside than on the dawn, showing the dawn‐dusk asymmetry. The densities on the duskside reach their maximum on 29 June 2018, close to the time of peak dust activity. These results are explained by considering the local time asymmetries in radiative heating of the lower atmosphere and subsequent expansion of the thermosphere due to PEDE‐2018. Furthermore, O/CO2 ratios below 220‐km altitude become one on the dawnside, whereas they are always <0.2 at the dusk. This indicates that radiative cooling is more effective on the dawnside than the duskside.
A Remote Sensing Technique to Upscale Methane Emission Flux in a Subtropical Peatland
Authors: Zhang Caiyun , Comas Xavier , Brodylo David
Published: September 2020

Quantification of methane (CH4) gas emission from peat is critical to understand CH4 budget from natural wetlands under a climate warming scenario. Previous studies have focused on prediction and mapping of CH4 emission flux using process‐based models, while application of statistical‐empirical models for upscaling spatially sparse in situ measurements is scarce. In this study, we developed an empirical remote sensing upscaling approach to estimate CH4 emission flux in the Everglades using limited in situ point‐based CH4 emission flux measurements and Landsat data during 2013–2018. We spatially and temporally linked in situ data with Landsat surface reflectance based on temporally composite data sets and developed an object‐based machine learning framework to model and map CH4 emission flux. An ensemble analysis of two machine learning models, k‐Nearest Neighbor (k‐NN) and Support Vector Machine (SVM), shows that the upscaling approach is promising for predicting CH4 emission flux with a R2 of 0.65 and 0.87 based on a fivefold cross‐validation for a dry season and wet season estimation, respectively. We generated emission flux map products that successfully revealed the spatial and temporal heterogeneity of CH4 emission within the dominant freshwater marsh ecosystem in the Everglades. We conclude that Landsat is promising for upscaling and monitoring CH4 emission flux and reducing the uncertainty in emission estimates from wetlands.
The ubiquitin ligase RNF181 stabilizes ERα and modulates breast cancer progression
Authors: Zhu Jian , Li Xin , Su Peng , Xue Min , Zang Yifeng , Ding Yinlu
Published: September 2020

ERα positive breast cancer accounts for 70% of breast malignancies. Compared with ERα negative types, ERα positive breast cancer could be effective controlled by endocrine therapy. However, more than half of the patients will develop endocrine resistance, making it an important clinical issue for breast cancer therapy. Endocrine resistance might be caused by multiple alternations, including the components of ERα signaling, during tumor progression. Thus, it is urgent and necessary to uncover the molecular mechanisms that controls ERα expression and stability to improve breast cancer therapeutics. In our current study, we identifies that the ubiquitin ligase RNF181 stabilizes ERα and facilitates breast cancer progression. The expression of RNF181 is correlated with ERα level in human breast tumors and relates to poor survival in endocrine-treated patients. RNF181 depletion inhibits breast cancer progression in vivo and in vitro, reduces ERα protein level and its target gene expression, such as PS2 and GREB1. Unbiased RNA sequencing analysis indicates RNF181 is necessary for ERα signature gene expression in whole genomic level. Immuno-precipitation assays indicate that RNF181 associates with ERα and promotes its stability possibly via inducing ERα K63-linked poly-ubiquitination. In conclusion, our data implicate a non-genomic mechanism by RNF181 via stabilizing ERα protein controls ERα target gene expression linked to breast cancer progression.
Changes in performance and bio-mathematical model performance predictions during 45 days of sleep restriction in a simulated space mission
Authors: Flynn-Evans Erin E. , Kirkley Crystal , Young Millennia , Bathurst Nicholas , Gregory Kevin , Vogelpohl Verena , End Albert , Hillenius Steven , Pecena Yvonne , Marquez Jessica J.
Published: September 2020

Lunar habitation and exploration of space beyond low-Earth orbit will require small crews to live in isolation and confinement while maintaining a high level of performance with limited support from mission control. Astronauts only achieve approximately 6 h of sleep per night, but few studies have linked sleep deficiency in space to performance impairment. We studied crewmembers over 45 days during a simulated space mission that included 5 h of sleep opportunity on weekdays and 8 h of sleep on weekends to characterize changes in performance on the psychomotor vigilance task (PVT) and subjective fatigue ratings. We further evaluated how well bio-mathematical models designed to predict performance changes due to sleep loss compared to objective performance. We studied 20 individuals during five missions and found that objective performance, but not subjective fatigue, declined from the beginning to the end of the mission. We found that bio-mathematical models were able to predict average changes across the mission but were less sensitive at predicting individual-level performance. Our findings suggest that sleep should be prioritized in lunar crews to minimize the potential for performance errors. Bio-mathematical models may be useful for aiding crews in schedule design but not for individual-level fitness-for-duty decisions.
Implementation of a red blood cell-optical (RBO) channel for detection of latent iron deficiency anaemia by automated measurement of autofluorescence-emitting red blood cells
Authors: Tougan Takahiro , Itagaki Sawako , Toya Yuji , Uchihashi Kinya , Horii Toshihiro
Published: September 2020

Iron deficiency is the most common and widespread nutritional disorder worldwide. The automated haematology analyser XN-30 (Sysmex, Kobe, Japan) was developed to detect malaria-infected red blood cells (RBCs) in human blood samples using flow cytometry. The optical system of the analyser detects autofluorescence (AF)-emitting RBCs containing iron-deficient haem groups and would aid in the diagnosis of anaemia resulting from iron deficiency. Here, an RBC-optical (RBO) channel was devised and implemented on the analyser. In vitro analyses showed that the analyser detected AF-emitting RBCs treated with 5-aminolevulinic acid. Furthermore, the analyser detected AF-emitting RBCs in mice fed a low iron diet and infected with a rodent malaria parasite; it could also be effectively used in humans. This study demonstrates that the analyser can quantitatively and reproducibly detect AF-emitting RBCs and measure other haematological parameters, suggesting its usefulness for the initial evaluation of latent iron deficiency anaemia in conjunction with the diagnosis of malaria.
A first evaluation of the usefulness of Kudzu starch in cultural heritage restoration
Authors: Lama E. , Veneranda M. , Prieto-Taboada N. , Hernando F. L. , Rodríguez Laso M. D. , Madariaga J. M.
Published: September 2020

In recent times, the use of natural and harmless products for the environment and restorer is taking place in the field of Cultural Heritage restoration. In this sense, wheat, rice and corn starches as adhesives, have suitable characteristics without toxicity risks. A new starch in this field, is the Kudzu, an almost pure compound (99.5% starch) that is processed by a natural way from a plant called Pueraria lobata. This is a preliminary study of the potential use of Kudzu starch for the restoration of Cultural Heritage, focusing, firstly, in its capacity as adhesive through a comparative evaluation with common starches. The accelerated aging process carried out proved that Kudzu ensures optimal chromatic behaviour. On the other hand, the main problem in starch paste is the biological colonization. The daidzein, a natural antimicrobial compound implicit in Kudzu starch, confirmed the resistance to microorganism in this preliminary approach. The evaluation of the adhesive capacity, and the reversibility of the starches, suggest that Kudzu starch is a valid adhesive in the field of paper restoration. Thus, the potential of this starch in the conservation of Cultural Heritage is evidenced and its use as cleaner, resistance to biological colonization and consolidant is promising.
Inducible EphA4 knockout causes motor deficits in young mice and is not protective in the SOD1G93A mouse model of ALS
Authors: Dominguez Sara L. , Earr Timothy , Dourado Michelle , Ngu Hai , Meilandt William J. , Hanson Jesse E.
Published: September 2020

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by motor neuron loss that ultimately leads to fatal paralysis. Reducing levels or function of the tyrosine kinase, ephrin type-A receptor 4 (EphA4), has been suggested as a potential approach for slowing disease progression in ALS. Because EphA4 plays roles in embryonic nervous system development, study of constitutive knockout (KO) of EphA4 in mice is limited due to confounding phenotypes with homozygous knockout. We used a tamoxifen-inducible EphA4 conditional KO mouse to achieve strong reduction of EphA4 levels in postnatal mice to test for protective effects in the SOD1G93A model of ALS. We found that EphA4 KO in young mice, but not older adult mice, causes defects in muscle function, consistent with a prolonged postnatal role for EphA4 in adolescent muscle growth. When testing the effects of inducible EphA4 KO at different timepoints in SOD1G93A mice, we found no benefits on motor function or disease pathology, including muscle denervation and motor neuron loss. Our results demonstrate deleterious effects of reducing EphA4 levels in juvenile mice and do not provide support for the hypothesis that widespread EphA4 reduction is beneficial in the SOD1G93A mouse model of ALS.
Cell type specific gene expression profiling reveals a role for complement component C3 in neutrophil responses to tissue damage
Authors: Houseright Ruth A. , Rosowski Emily E. , Lam Pui-Ying , Tauzin Sebastien J. M. , Mulvaney Oscar , Dewey Colin N. , Huttenlocher Anna
Published: September 2020

Tissue damage induces rapid recruitment of leukocytes and changes in the transcriptional landscape that influence wound healing. However, the cell-type specific transcriptional changes that influence leukocyte function and tissue repair have not been well characterized. Here, we employed translating ribosome affinity purification (TRAP) and RNA sequencing, TRAP-seq, in larval zebrafish to identify genes differentially expressed in neutrophils, macrophages, and epithelial cells in response to wounding. We identified the complement pathway andc3a.1, homologous to the C3 component of human complement, as significantly increased in neutrophils in response to wounds.c3a.1−/−zebrafish larvae have impaired neutrophil directed migration to tail wounds with an initial lag in recruitment early after wounding. Moreover,c3a.1−/−zebrafish larvae have impaired recruitment to localized bacterial infections and reduced survival that is, at least in part, neutrophil mediated. Together, our findings support the power of TRAP-seq to identify cell type specific changes in gene expression that influence neutrophil behavior in response to tissue damage.
The comparison of nailfold videocapillaroscopy findings between anti-melanoma differentiation-associated gene 5 antibody and anti-aminoacyl tRNA synthetase antibody in patients with dermatomyositis complicated by interstitial lung disease
Authors: Wakura Reiko , Matsuda Shogo , Kotani Takuya , Shoda Takeshi , Takeuchi Tohru
Published: September 2020

Dermatomyositis (DM) is frequently complicated by interstitial lung disease (ILD), which increases mortality. This study aims to elucidate the clinical significance of nailfold videocapillaroscopy (NVC) on assessing the disease activity and prognosis of DM-ILD. We compared the NVC findings between anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibody-positive and anti-aminoacyl tRNA synthetase (anti-ARS) antibody-positive patients, the survival and ILD-related death groups, and examined the association of NVC findings with prognostic factors of DM-ILD. The median scores of microhemorrhage and capillary disorganization in the anti-MDA5 antibody-positive group were significantly higher than those in the anti-ARS antibody-positive group (P = 0.012 and 0.044, respectively). In contrast, the median scores of tortuous capillaries in the anti-ARS antibody-positive group were significantly higher than those in the anti-MDA5 antibody-positive group (P = 0.002). The median scores of microhemorrhage was significantly higher in the ILD-related death group than the survival group (P = 0.02). The scores of microhemorrhage, capillary disorganization, and neoangiogenesis correlated with known poor prognosis factors of DM-ILD. Additionally, the scores of microhemorrhage and capillary loss correlated significantly with the total fibrosis scores of chest high-resolution computed tomography. These findings suggest that NVC is a useful tool for assessing the disease activity and prognosis of DM-ILD.
A prospective study of lung disease in a cohort of early rheumatoid arthritis patients
Authors: Robles-Pérez A. , Luburich P. , Bolivar S. , Dorca J. , Nolla J. M. , Molina-Molina M. , Narváez J.
Published: September 2020

Lung disease is common in patients with rheumatoid arthritis (RA). The onset of lung involvement in RA is not well known. The objective is to describe the features and evolution of lung involvement in early RA, its relationship with disease activity parameters, smoking and treatments. Consecutive patients with early RA without respiratory symptoms were included and tracked for 5 years. Lung assessment included clinical, radiological and pulmonary function tests at diagnosis and during follow-up. Peripheral blood parameters (erythrocyte sedimentation rate, C reactive protein, rheumatoid factor and anti-citrullinated peptide autoantibodies) and scales of articular involvement, such as DAS28-CRP, were evaluated. 40 patients were included and 32 completed the 5-year follow up. 13 patients presented lung involvement in the initial 5 years after RA diagnosis, 3 of them interstitial lung disease. Significant decrease of diffusion lung transfer capacity of carbon monoxide over time was observed in six patients, 2 of them developed interstitial lung disease. DLCO decrease was correlated with higher values of CRP and ESR at diagnosis. Methotrexate was not associated with DLCO deterioration or lung disease development. Subclinical progressive lung disease correlates with RA activity parameters. Smoking status and methotrexate were not associated with development or progression of lung disease.
Naphthoquinone-derivative as a synthetic compound to overcome the antibiotic resistance of methicillin-resistant S. aureus
Authors: Song Ronghui , Yu Bing , Friedrich Dirk , Li Junfeng , Shen Hao , Krautscheid Harald , Huang Songping D. , Kim Min-Ho
Published: September 2020

The treatment of Staphylococcus aureus (S. aureus) infections has become more difficult due to the emergence of multidrug resistance in the bacteria. Here, we report the synthesis of a lawsone (2-hydroxy-1,4-naphthoquinone)-based compound as an antimicrobial agent against methicillin-resistant S. aureus (MRSA). A series of lawsone-derivative compounds were synthesized by means of tuning the lipophilicity of lawsone and screened for minimum inhibitory concentrations against MRSA to identify a candidate compound that possesses a potent antibacterial activity. The identified lawsone-derivative compound exhibited significantly improved drug resistance profiles against MRSA compared to conventional antibiotics. The therapeutic efficacy of the compound was validated using murine models of wound infection as well as non-lethal systemic infection induced by MRSA. Our study further revealed the multifaceted modes of action of the compound, mediated by three distinctive mechanisms: (1) cell membrane damage, (2) chelation of intracellular iron ions, and (3) generation of intracellular reactive oxygen species.
Three types of copper derivatives formed by CuCl2·2H2O interaction with (Z)-3-aryl-2-(methylthio)-5-(pyridine-2-ylmethylene)-3,5-dihydro-4H-imidazol-4-ones
Authors: Guk Dmitry , Naumov Alexei , Krasnovskaya Olga , Tafeenko Viktor , Moiseeeva Anna , Pergushov Vladimir , Melnikov Michail , Zyk Nikolai , Majouga Alexander , Belolglazkina Elena
Published: September 2020

CuCl2·2H2O reacts with 5-(pyridine-2-ylmethylene)-thiohydantoin derivatives (L) in reducing solvent-forming compounds with a composition of CuII(L)Cl2, CuI(L)Cl, and (L + H)+CuICl2−.
The adsorption behavior of lithium on spinel titanium oxide nanosheets with exposed (1−14) high-index facets
Authors: Zhao Bing , Guo Min , Qian Zhiqiang , Li Jun , Wu Zhijian , Liu Zhong
Published: September 2020

The adsorption behavior of H4Ti5O12 nanosheets was systematically investigated, and the reasons for the excellent recycling performance were elucidated via DFT calculations.