bluuebunny/crossref_metadata_2025 huggingface dataset:
CoMaLit – VI. Intrinsic scatter in stacked relations. The weak lensing AMICO galaxy clusters in KiDS-DR3
Authors: Sereno Mauro , Ettori Stefano , Lesci Giorgio F , Marulli Federico , Maturi Matteo , Moscardini Lauro , Radovich Mario , Bellagamba Fabio , Roncarelli Mauro
Published: July 2020

Unbiased and precise mass calibration of galaxy clusters is crucial to fully exploit galaxy clusters as cosmological probes. Stacking of weak lensing (WL) signal allows us to measure observable–mass relations down to less massive haloes without extrapolation. We propose a Bayesian inference method to constrain the intrinsic scatter of the mass proxy in stacked analyses. The scatter of the stacked data is rescaled with respect to the individual scatter based on the number of binned clusters. We apply this method to the galaxy clusters detected with the AMICO (Adaptive Matched Identifier of Clustered Objects) algorithm in the third data release of the Kilo-Degree Survey. The results confirm the optical richness as a low-scatter mass proxy. Based on the optical richness and the calibrated WL mass–richness relation, mass of individual objects down to $\sim\! 10^{13}\, \mathrm{M}_\odot$ can be estimated with a precision of ∼20 per cent.
Oxygen loss from simulated galaxies and the metal flow main sequence: predicting the dependence on mass and environment
Authors: Taylor Philip , Kobayashi Chiaki , Kewley Lisa J
Published: July 2020

We predict the mass fraction of oxygen lost from galaxies in a cosmological simulation as a function of stellar mass and environment at the present day. The distribution with stellar mass is bimodal, separating star-forming and quenched galaxies. The metallicity of gas and stars is self-consistently calculated using a chemical evolution model that includes Type II and Ia supernovae, hypernovae, and asymptotic giant branch stars. The mass of oxygen lost from each galaxy is calculated by comparing the existing oxygen in gas and stars in the galaxy to the oxygen that should have been produced by the present-day population of stars. More massive galaxies are able to retain a greater fraction of their metals (∼100 per cent) than low-mass galaxies (∼40–70 per cent). As in the star formation main sequence, star-forming galaxies follow a tight relationship also in terms of oxygen mass lost – a metal flow main sequence – whereas massive quenched galaxies tend to have lost a greater fraction of oxygen (up to 20 per cent), due to active galactic nucleus-driven winds. The amount of oxygen lost by satellite galaxies depends on the details of their interaction history, and those in richer groups tend to have lost a greater fraction of their oxygen. Observational estimates of metal retention in galaxies will provide a strong constraint on models of galaxy evolution.
An application of a solar-type dynamo model for ε Eridani
Authors: Buccino A P , Sraibman L , Olivar P M , Minotti F O
Published: July 2020

During the last decade, the relation between activity cycle periods and stellar parameters has received special attention. The construction of reliable registries of activity reveals that solar-type stars exhibit activity cycles with periods from few years to decades and, in some cases, long and short activity cycles coexist suggesting that two dynamos could operate in these stars. In particular, ε Eridani is an active young K2V star (0.8 Gyr), which exhibits short and long-term chromospheric cycles of ∼3 and ∼13-yr periods. Additionally, between 1985 and 1992, the star went through a broad activity minimum, similar to the solar Maunder Minimum state.

Motivated by these results, we found in ε Eridani a great opportunity to test the dynamo theory. Based on the model developed in Sraibman & Minotti, in this work we built a non-linear axisymmetric dynamo for ε Eridani. The time series of the simulated magnetic field components near the surface integrated in all the stellar disc exhibits both the long and short activity cycles with periods similar to the ones detected from observations and also time intervals of low activity that could be associated with the broad Minimum. The short activity cycle associated with the magnetic reversal could be explained by the differential rotation, while the long cycle is associated with the meridional mass flows induced by the Lorentz force. In this way, we show that a single non-linear dynamo model derived from first principles with accurate stellar parameters could reproduce coexisting activity cycles.
NIR counterparts to ULXs (III): completing the photometric survey and selected spectroscopic results★
Authors: López K M , Heida M , Jonker P G , Torres M A P , Roberts T P , Walton D J , Moon D-S , Harrison F A
Published: July 2020

We present results from the remaining sources in our search for near-infrared (NIR) candidate counterparts to ultraluminous X-ray sources (ULXs) within ≃10 Mpc. We observed 23 ULXs in 15 galaxies and detected NIR candidate counterparts to 6 of them. Two of these have an absolute magnitude consistent with a single red supergiant (RSG). Three counterparts are too bright for an RSG and spatially extended, and thus we classify them as stellar clusters. The other candidate is too faint for an RSG. Additionally, we present the results of our NIR spectroscopic follow-up of five sources: four originally classified as RSG and one as a stellar cluster on the basis of previous photometry. The stellar cluster candidate is actually a nebula. Of the four RSG candidates, one source has a broad H α emission line redshifted by ∼z = 1, making it a background active galactic nucleus (AGN). Two other sources show stellar spectra consistent with them being RSGs. The final RSG candidate is too faint to classify, but does not show strong (nebular) emission lines in its spectrum. After our search for NIR counterparts to 113 ULXs, where we detected a candidate counterpart for 38 ULXs, we have spectroscopically confirmed the nature of 12: 5 sources are nebulae, 1 source is not classified, 1 source is an AGN, and 5 are RSGs. These possible five ULX–RSG binary systems would constitute ${\simeq} (4 \pm 2){{\ \rm per\ cent}}$ of the observed ULXs, a fraction almost four times larger than what was predicted by binary evolution simulations.
UV dust attenuation as a function of stellar mass and its evolution with redshift
Authors: Bogdanoska Jana , Burgarella Denis
Published: July 2020

Studying the ultraviolet dust attenuation, as well as its relation to other galaxy parameters such as the stellar mass, plays an important role in multiwavelength research. This work relates the dust attenuation to the stellar mass of star-forming galaxies, and its evolution with redshift. A sample of galaxies with an estimate of the dust attenuation computed from the infrared excess was used. The dust attenuation versus stellar mass data, separated in redshift bins, was modelled by a single parameter linear function, assuming a non-zero constant apparent dust attenuation for low-mass galaxies. But the origin of this effect is still to be determined and several possibilities are explored (actual high dust content, variation of the dust-to-metal ratio, variation of the stars–dust geometry). The best-fitting parameter of this model is then used to study the redshift evolution of the cosmic dust attenuation and is found to be in agreement with results from the literature. This work also gives evidence to a redshift evolution of the dust attenuation–stellar mass relationship, as is suggested by recent works in the highest redshift range.
A systematic study of CO2 planetary atmospheres and their link to the stellar environment
Authors: Petralia A , Alei E , Aresu G , Locci D , Cecchi-Pestellini C , Micela G , Claudi R , Ciaravella A
Published: July 2020

The Milky Way Galaxy is literally teeming with exoplanets; thousands of planets have been discovered, with thousands more planet candidates identified. Terrestrial-like planets are quite common around other stars, and are expected to be detected in large numbers in the future. Such planets are the primary targets in the search for potentially habitable conditions outside the Solar system. Determining the atmospheric composition of exoplanets is mandatory to understand their origin and evolution, as atmospheric processes play crucial roles in many aspects of planetary architecture. In this work we construct and exploit a 1D radiative transfer model based on the discrete-ordinates method in plane-parallel geometry. Radiative results are linked to a convective flux that redistributes energy at any altitude producing atmospheric profiles in radiative–convective equilibrium. The model has been applied to a large number (6250) of closely dry synthetic CO2 atmospheres, and the resulting pressure and thermal profiles have been interpreted in terms of parameter variability. Although less accurate than 3D general circulation models, not properly accounting for e.g. clouds and atmospheric and ocean dynamics, 1D descriptions are computationally inexpensive and retain significant value by allowing multidimensional parameter sweeps with relative ease.
Multitracer extension of the halo model: probing quenching and conformity in eBOSS
Authors: Alam Shadab , Peacock John A , Kraljic Katarina , Ross Ashley J , Comparat Johan
Published: July 2020

We develop a new Multitracer Halo Occupation Distribution (MTHOD) framework for the galaxy distribution and apply it to the extended Baryon Oscillation Spectroscopic Survey (eBOSS) final data between z = 0.7 − 1.1. We obtain a best fitting MTHOD  for each tracer and describe the host halo properties of these galaxies. The mean halo masses for LRGs, ELGs, and QSOs are found to be $1.9 \times 10^{13} \, h^{-1}M_\odot$, $1.1 \times 10^{12} \, h^{-1}M_\odot$, and $5 \times 10^{12} \, h^{-1}M_\odot$ respectively in the eBOSS data. We use the MTHOD  framework to create mock galaxy catalogues and predict auto- and cross-correlation functions for all the tracers. Comparing these results with data, we investigate galactic conformity, the phenomenon whereby the properties of neighbouring galaxies are mutually correlated in a manner that is not captured by the basic halo model. We detect 1-halo conformity at more than 3σ statistical significance, while obtaining upper limits on 2-halo conformity. We also look at the environmental dependence of the galaxy quenching efficiency and find that halo mass driven quenching successfully explains the behaviour in high density regions, but it fails to describe the quenching efficiency in low density regions. In particular, we show that the quenching efficiency in low density filaments is higher in the observed data, as compared to the prediction of the MTHOD with halo mass driven quenching. The mock galaxy catalogue constructed in this paper is publicly available on this website1.
Filament intersections and cold dense cores in Orion A North
Authors: Zhang Chao , Ren Zhiyuan , Wu Jingwen , Li Di , Zhu Lei , Zhang Qizhou , Mardones Diego , Wang Chen , Shi Hui , Yue Nannan , Luo Gan , Xie Jinjin , Jiao Sihan , Liu Shu , Xu Xuefang , Wang Shen
Published: July 2020

We studied the filament structures and cold dense cores in OMC-2,3 region in Orion A North molecular cloud using the high-resolution N2H+ (1-0) spectral cube observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). The filament network over a total length of 2 pc is found to contain 170 intersections and 128 candidate dense cores. The dense cores are all displaced from the infrared point sources (possible young stars), and the major fraction of cores (103) are located around the intersections. Towards the intersections, there is also an increasing trend for the total column density Ntot as well as the power-law index of the column-density Probability Distribution Function (N-PDF), suggesting that the intersections would in general have more significant gas assembly than the other part of the filament paths. The virial analysis shows that the dense cores mostly have virial mass ratio of αvir = Mvir/Mgas < 1.0, suggesting them to be bounded by the self-gravity. In the mean time, only about 23 per cent of the cores have critical mass ratio of αcrit = Mcrit/Mgas < 1.0, suggesting them to be unstable against core collapse. Combining these results, it shows that the major fraction of the cold starless and possible pre-stellar cores in OMC-2,3 are being assembled around the intersections, and currently in a gravitationally bound state. But more extensive core-collapse and star formation may still require continuous core mass growth or other perturbations.
Analysis of the He i chromosphere in relation to the magnetic field activity over solar cycle time periods
Authors: Li K J , Feng W
Published: July 2020

Solar synoptic maps of both He i 10 830 Å intensity and the magnetic field, which are observed by the Vacuum Telescope at National Solar Observatory/Kitt Peak from 2005 July to 2013 March are utilized to study relationship of He i intensity of the weakly magnetized chromosphere with the respective magnetic field strength. Strong absorption in He i intensity presents the butterfly-pattern latitude migration zone as active regions do, indicating that strong magnetic field corresponds to high-temperature structures of the active chromosphere. For He i intensity and magnetic field strength, their distribution at the time-latitude coordinate and their time series at each of the 180 measurement latitude are found to be significantly negatively correlated with each other in most cases. When a solar hemisphere is divided into three latitude bands: low, middle, and high latitude bands, and even after large magnetic field values not taken into account, they are still negatively correlated in most cases, and further when large magnetic field values are subtracted He i intensity varies more sensitively with magnetic field strength than the corresponding cases when large magnetic field values are not subtracted. He i intensity in the quiet chromosphere thus mainly presents a negative correlation with the magnetic field, and the heating of the quiet chromosphere is inferred to be caused mainly by small-scale magnetic elements.
Inverse-Compton scattering in the resolved jet of the high-redshift quasar PKS J1421−0643
Authors: Worrall D M , Birkinshaw M , Marshall H L , Schwartz D A , Siemiginowska A , Wardle J F C
Published: July 2020

Despite the fact that kpc-scale inverse-Compton (iC) scattering of cosmic microwave background (CMB) photons into the X-ray band is mandated, proof of detection in resolved quasar jets is often insecure. High redshift provides favourable conditions due to the increased energy density of the CMB, and it allows constraints to be placed on the radio synchrotron-emitting electron component at high energies that are otherwise inaccessible. We present new X-ray, optical, and radio results from Chandra, HST, and the VLA for the core and resolved jet in the z = 3.69 quasar PKS J1421−0643. The X-ray jet extends for about 4.5 arcsec (32 kpc projected length). The jet’s radio spectrum is abnormally steep and consistent with electrons being accelerated to a maximum Lorentz factor of about 5000. Results argue in favour of the detection of iC X-rays for modest magnetic field strength of a few nT, Doppler factor of about 4, and viewing angle of about 15°, and predict the jet to be largely invisible in most other spectral bands including the far- and mid-infrared and high-energy gamma-ray. The jet power is estimated to be about 3 × 1046 erg s−1 which is of order a tenth of the quasar bolometric power, for an electron–positron jet. The jet radiative power is only about 0.07 per cent of the jet power, with a smaller radiated power ratio if the jet contains heavy particles, so most of the jet power is available for heating the intergalactic medium.
Towards a multitracer timeline of star formation in the LMC – I. Deriving the lifetimes of H i clouds
Authors: Ward Jacob L , Chevance Mélanie , Kruijssen J M Diederik , Hygate Alexander P S , Schruba Andreas , Longmore Steven N
Published: July 2020

The time-scales associated with the various stages of the star formation process remain poorly constrained. This includes the earliest phases of star formation, during which molecular clouds condense out of the atomic interstellar medium. We present the first in a series of papers with the ultimate goal of compiling the first multitracer timeline of star formation, through a comprehensive set of evolutionary phases from atomic gas clouds to unembedded young stellar populations. In this paper, we present an empirical determination of the lifetime of atomic clouds using the Uncertainty Principle for Star Formation formalism, based on the de-correlation of H α and H i emission as a function of spatial scale. We find an atomic gas cloud lifetime of 48$^{+13}_{-8}$ Myr. This time-scale is consistent with the predicted average atomic cloud lifetime in the LMC (based on galactic dynamics) that is dominated by the gravitational collapse of the mid-plane ISM. We also determine the overlap time-scale for which both H i and H α emissions are present to be very short (tover < 1.7 Myr), consistent with zero, indicating that there is a near-to-complete phase change of the gas to a molecular form in an intermediary stage between H i clouds and H ii regions. We utilize the time-scales derived in this work to place empirically determined limits on the time-scale of molecular cloud formation. By performing the same analysis with and without the 30 Doradus region included, we find that the most extreme star-forming environment in the LMC has little effect on the measured average atomic gas cloud lifetime. By measuring the lifetime of the atomic gas clouds, we place strong constraints on the physics that drives the formation of molecular clouds and establish a solid foundation for the development of a multitracer timeline of star formation in the LMC.
Modelling the Milky Way – I. Method and first results fitting the thick disc and halo with DES-Y3 data
Authors: Pieres A , Girardi L , Balbinot E , Santiago B , da Costa L N , Carnero Rosell A , Pace A B , Bechtol K , Groenewegen M A T , Drlica-Wagner A , Li T S , Maia M A G , Ogando R L C , dal Ponte M , Diehl H T , Amara A , Avila S , Bertin E , Brooks D , Burke D L , Carrasco Kind M , Carretero J , De Vicente J , Desai S , Eifler T F , Flaugher B , Fosalba P , Frieman J , García-Bellido J , Gaztanaga E , Gerdes D W , Gruen D , Gruendl R A , Gschwend J , Gutierrez G , Hollowood D L , Honscheid K , James D J , Kuehn K , Kuropatkin N , Marshall J L , Miquel R , Plazas A A , Sanchez E , Serrano S , Sevilla-Noarbe I , Sheldon E , Smith M , Soares-Santos M , Sobreira F , Suchyta E , Swanson M E C , Tarle G , Thomas D , Vikram V , Walker A R
Published: July 2020

We present a technique to fit the stellar components of the Galaxy by comparing Hess Diagrams (HDs) generated from trilegal models to real data. We apply this technique, which we call mwfitting, to photometric data from the first 3 yr of the Dark Energy Survey (DES). After removing regions containing known resolved stellar systems such as globular clusters, dwarf galaxies, nearby galaxies, the Large Magellanic Cloud, and the Sagittarius Stream, our main sample spans a total area of ∼2300 deg2. We further explore a smaller subset (∼1300 deg2) that excludes all regions with known stellar streams and stellar overdensities. Validation tests on synthetic data possessing similar properties to the DES data show that the method is able to recover input parameters with a precision better than 3 per cent. We fit the DES data with an exponential thick disc model and an oblate double power-law halo model. We find that the best-fitting thick disc model has radial and vertical scale heights of 2.67 ± 0.09 kpc and 925 ± 40 pc, respectively. The stellar halo is fit with a broken power-law density profile with an oblateness of 0.75 ± 0.01, an inner index of 1.82 ± 0.08, an outer index of 4.14 ± 0.05, and a break at 18.52 ± 0.27 kpc from the Galactic centre. Several previously discovered stellar overdensities are recovered in the residual stellar density map, showing the reliability of mwfitting in determining the Galactic components. Simulations made with the best-fitting parameters are a promising way to predict Milky Way star counts for surveys such as the LSST and Euclid.
Disc formation and jet inclination effects in common envelopes
Authors: López-Cámara Diego , Moreno Méndez Enrique , De Colle Fabio
Published: July 2020

The evolution and physics of the common envelope (CE) phase are still not well understood. Jets launched from a compact object during this stage may define the evolutionary outcome of the binary system. We focus on the case in which jets are launched from a neutron star (NS) engulfed in the outer layers of a red giant (RG). We run a set of three-dimensional hydrodynamical simulations of jets with different luminosities and inclinations. The luminosity of the jet is self-regulated by the mass accretion rate and an efficiency η. Depending on the value of η the jet can break out of the previously formed bulge (‘successful jet’) and aligns against the incoming wind, in turn, it will realign in favour of the direction of the wind. The jet varies in size and orientation and may present quiescent and active epochs. The inclination of the jet and the Coriolis and centrifugal forces, only slightly affect the global evolution. As the accretion is hypercritical, and the specific angular momentum is above the critical value for the formation of a disc, we infer the formation of a disc and launching of jets. The discs’ mass and size would be ∼10−2 M⊙ and ≳1010 cm, and it may have rings with different rotation directions. In order to have a successful jet from a white dwarf, the ejection process needs to be very efficient (η ∼ 0.5). For main-sequence stars, there is not enough energy reservoir to launch a successful jet.
The power of coordinate transformations in dynamical interpretations of Galactic structure
Authors: Hunt Jason A S , Johnston Kathryn V , Pettitt Alex R , Cunningham Emily C , Kawata Daisuke , Hogg David W
Published: July 2020

Gaia DR2 has provided an unprecedented wealth of information about the positions and motions of stars in our Galaxy and has highlighted the degree of disequilibria in the disc. As we collect data over a wider area of the disc, it becomes increasingly appealing to start analysing stellar actions and angles, which specifically label orbit space, instead of their current phase space location. Conceptually, while $\bar {x}$ and $\bar {v}$ tell us about the potential and local interactions, grouping in action puts together stars that have similar frequencies and hence similar responses to dynamical effects occurring over several orbits. Grouping in actions and angles refines this further to isolate stars that are travelling together through space and hence have shared histories. Mixing these coordinate systems can confuse the interpretation. For example, it has been suggested that by moving stars to their guiding radius, the Milky Way spiral structure is visible as ridge-like overdensities in the Gaia data (Khoperskov et al. 2020). However, in this work, we show that these features are in fact the known kinematic moving groups, both in the Lz − ϕ and the vR − vϕ planes. Using simulations, we show how this distinction will become even more important as we move to a global view of the Milky Way. As an example, we show that the radial velocity wave seen in the Galactic disc in Gaia and APOGEE should become stronger in the action-angle frame, and that it can be reproduced by transient spiral structure.
Time evolution of cyclotron line of Her X-1: a detailed statistical analysis including new AstroSat data
Authors: Bala S , Bhattacharya D , Staubert R , Maitra C
Published: July 2020

The cyclotron line feature in the X-ray spectrum of the accretion-powered pulsar Her X-1 has been observed and monitored for over three decades. The line energy exhibited a slow secular decline over the period 1995–2014, with a possible (not confirmed) indication of a reversal thereafter. Recent works have shown that the temporal evolution of the line energy may be modelled as a flattening after an earlier decrease until MJD 55400 (±200). In this work, we present the results of AstroSat observations in the context of earlier data and offer a common interpretation through a detailed study of temporal and flux dependence. We find that the variation of the line energy does not support an upward trend but is consistent with the reported flattening after an earlier decrease until MJD $54487^{+515}_{-469}$.
Gamma-ray counterparts of 2WHSP high-synchrotron-peaked BL Lac objects as possible signatures of ultra-high-energy cosmic ray emission
Authors: Toomey Michael W , Oikonomou Foteini , Murase Kohta
Published: July 2020

We present a search for high-energy γ-ray emission from 566 Active Galactic Nuclei at redshift z > 0.2, from the 2WHSP catalogue of high-synchrotron peaked BL Lac objects with 8 yr of Fermi-LAT data. We focus on a redshift range where electromagnetic cascade emission induced by ultra-high-energy cosmic rays can be distinguished from leptonic emission based on the spectral properties of the sources. Our analysis leads to the detection of 160 sources above ≈5σ (TS ≥25) in the 1–300 GeV energy range. By discriminating significant sources based on their γ-ray fluxes, variability properties, and photon index in the Fermi-LAT energy range, and modelling the expected hadronic signal in the TeV regime, we select a list of promising sources as potential candidate ultra-high-energy cosmic ray emitters for follow-up observations by Imaging Atmospheric Cherenkov Telescopes.
NGC 474 as viewed with KCWI: diagnosing a shell galaxy
Authors: Alabi Adebusola B , Ferré-Mateu Anna , Forbes Duncan A , Romanowsky Aaron J , Brodie Jean P
Published: July 2020

We present new spectra obtained using Keck/KCWI and perform kinematics and stellar population analyses of the shell galaxy NGC 474, from both the galaxy centre and a region from the outer shell. We show that both regions have similarly extended star formation histories although with different stellar population properties. The central region of NGC 474 is dominated by intermediate-aged stars (8.3 ± 0.3 Gyr) with subsolar metallicity ([Z/H] = −0.24 ± 0.07 dex) while the observed shell region, which hosts a substantial population of younger stars, has a mean luminosity-weighted age of 4.0 ± 0.5 Gyr with solar metallicities ([Z/H] = −0.03 ± 0.09 dex). Our results are consistent with a scenario in which NGC 474 experienced a major to intermediate merger with a log$(M_*/\rm M_\odot) \sim 10$ mass satellite galaxy at least ${\sim}2$ Gyr ago which produced its shell system. This work shows that the direct spectroscopic study of low-surface brightness stellar features, such as shells, is now feasible and opens up a new window to understanding galaxy formation and evolution.
Formation of massive stars under protostellar radiation feedback: very metal-poor stars
Authors: Fukushima Hajime , Hosokawa Takashi , Chiaki Gen , Omukai Kazuyuki , Yoshida Naoki , Kuiper Rolf
Published: July 2020

We study the formation of very metal-poor stars under protostellar radiative feedback effect. We use cosmological simulations to identify low-mass dark matter haloes and star-forming gas clouds within them. We then follow protostar formation and the subsequent long-term mass accretion phase of over one million years using two-dimensional radiation-hydrodynamics simulations. We show that the critical physical process that sets the final mass is the formation and expansion of a bipolar H ii region. The process is similar to the formation of massive primordial stars, but radiation pressure exerted on dust grains also contributes to halting the accretion flow in the low-metallicity case. We find that the net feedback effect in the case with metallicity Z = 10−2 Z⊙ is stronger than in the case with Z ∼ 1 Z⊙. With decreasing metallicity, the radiation-pressure effect becomes weaker, but photoionization heating of the circumstellar gas is more efficient owing to the reduced dust attenuation. In the case with Z = 10−2 Z⊙, the central star grows as massive as 200 solar masses, similarly to the case of primordial star formation. We conclude that metal-poor stars with a few hundred solar masses can be formed by gas accretion despite the strong radiative feedback.
Synergic toxic effects of food contaminant mixtures in human cells
Authors: Kopp Benjamin , Sanders Pascal , Alassane-Kpembi Imourana , Fessard Valérie , Zalko Daniel , Le Hégarat Ludovic , Audebert Marc
Published: July 2020

Humans are exposed to multiple exogenous substances, notably through food consumption. Many of these compounds are suspected to impact human health, and their combination could exacerbate their harmful effects. We previously observed in human cells that, among the six most prevalent food contaminant complex mixtures identified in the French diet, synergistic interactions between component appeared in two mixtures compared with the response with the chemicals alone. In the present study, we demonstrated in human cells that these properties are driven only by two heavy metals in each mixture: tellurium (Te) with cadmium (Cd) and Cd with inorganic arsenic (As), respectively. It appeared that the predicted effects for these binary mixtures using the mathematical model of Chou and Talalay confirmed synergism between these heavy metals. Based on different cell biology experiments (cytotoxicity, genotoxicity, mutagenesis and DNA repair inhibition experiments), a detailed mechanistic analysis of these two mixtures suggests that concomitant induction of oxidative DNA damage and decrease of their repair capacity contribute to the synergistic toxic effect of these chemical mixtures. Overall, these results may have broad implications for the fields of environmental toxicology and chemical mixture risk assessment.
An NMR-based approach reveals the core structure of the functional domain of SINEUP lncRNAs
Authors: Ohyama Takako , Takahashi Hazuki , Sharma Harshita , Yamazaki Toshio , Gustincich Stefano , Ishii Yoshitaka , Carninci Piero
Published: July 2020

Long non-coding RNAs (lncRNAs) are attracting widespread attention for their emerging regulatory, transcriptional, epigenetic, structural and various other functions. Comprehensive transcriptome analysis has revealed that retrotransposon elements (REs) are transcribed and enriched in lncRNA sequences. However, the functions of lncRNAs and the molecular roles of the embedded REs are largely unknown. The secondary and tertiary structures of lncRNAs and their embedded REs are likely to have essential functional roles, but experimental determination and reliable computational prediction of large RNA structures have been extremely challenging. We report here the nuclear magnetic resonance (NMR)-based secondary structure determination of the 167-nt inverted short interspersed nuclear element (SINE) B2, which is embedded in antisense Uchl1 lncRNA and upregulates the translation of sense Uchl1 mRNAs. By using NMR ‘fingerprints’ as a sensitive probe in the domain survey, we successfully divided the full-length inverted SINE B2 into minimal units made of two discrete structured domains and one dynamic domain without altering their original structures after careful boundary adjustments. This approach allowed us to identify a structured domain in nucleotides 31–119 of the inverted SINE B2. This approach will be applicable to determining the structures of other regulatory lncRNAs.
Biochemical and structural basis for YTH domain of human YTHDC1 binding to methylated adenine in DNA
Authors: Woodcock Clayton B , Horton John R , Zhou Jujun , Bedford Mark T , Blumenthal Robert M , Zhang Xing , Cheng Xiaodong
Published: July 2020

The recently characterized mammalian writer (methyltransferase) and eraser (demethylase) of the DNA N6-methyladenine (N6mA) methyl mark act on single-stranded (ss) and transiently-unpaired DNA. As YTH domain-containing proteins bind N6mA-containing RNA in mammalian cells, we investigated whether mammalian YTH domains are also methyl mark readers of N6mA DNA. Here, we show that the YTH domain of YTHDC1 (known to localize in the nucleus) binds ssDNA containing N6mA, with a 10 nM dissociation constant. This binding is stronger by a factor of 5 than in an RNA context, tested under the same conditions. However, the YTH domains of YTHDF2 and YTHDF1 (predominantly cytoplasmic) exhibited the opposite effect with ∼1.5–2× stronger binding to ssRNA containing N6mA than to the corresponding DNA. We determined two structures of the YTH domain of YTHDC1 in complex with N6mA-containing ssDNA, which illustrated that YTHDC1 binds the methylated adenine in a single-stranded region flanked by duplexed DNA. We discuss the hypothesis that the writer-reader-eraser of N6mA-containining ssDNA is associated with maintaining genome stability. Structural comparison of YTH and SRA domains (the latter a DNA 5-methylcytosine reader) revealed them to be diverse members of a larger family of DNA/RNA modification readers, apparently having originated from bacterial modification-dependent restriction enzymes.
Parvovirus B19-Infected Tubulointerstitial Nephritis in Hereditary Spherocytosis
Authors: Nishiyama Kei , Watanabe Yuka , Ishimura Masataka , Tetsuhara Kenichi , Imai Takashi , Kanemasa Hikaru , Ueki Kenji , Motomura Yoshitomo , Kaku Noriyuki , Sakai Yasunari , Imadome Ken-Ichi , Ohga Shouichi
Published: July 2020

Background

Human parvovirus B19 (B19V) causes glomerulopathy or microangiopathy, but not tubulopathy. We experienced an 11-year-old girl with spherocytosis who developed acute kidney injury on a primary infection of B19V. She presented with anuria, encephalopathy, thrombocytopenia, and coagulopathy, along with no apparent aplastic crisis.

Methods

Continuous hemodiafiltration, immunoglobulin, and intensive therapies led to a cure.

Results

A kidney biopsy resulted in a histopathological diagnosis of tubulointerstitial nephritis without immune deposits. The virus capsid protein was limitedly expressed in the tubular epithelial cells with infiltrating CD8-positive cells.

Conclusions

Viral and histopathological analyses first demonstrated B19-infected tubulointerstitial nephritis due to the aberrant viremia with hereditary spherocytosis.
Complex scaling: Physics of unbound light nuclei and perspective
Authors: Myo Takayuki , Katō Kiyoshi
Published: July 2020

The complex scaling method (CSM) is one of the most powerful methods of describing the resonances with complex energy eigenstates based on non-Hermitian quantum mechanics. We present the basic application of CSM to the properties of the unbound phenomena of light nuclei. In particular, we focus on many-body resonant and non-resonant continuum states observed in unstable nuclei. We also investigate the continuum level density (CLD) in the scattering problem in terms of the Green’s function with CSM. We discuss the explicit effects of resonant and non-resonant contributions in CLD and transition strength functions.
More music, more health!
Authors: Raglio Alfredo
Published: July 2020

For several decades, music has been used more and more frequently and consciously as a mean of care to reduce or stabilize symptoms and/or complications arising therefrom. This has been the case with several diseases and conditions. Indeed, music also gives pleasure, promotes well-being, facilitates the expression and regulation of emotions and improves communication and relationships between individuals. The basis underlying the therapeutic potential of music are to be considered in relation to the extensive action that music itself exerts on the brain but also on vital signs and neurochemical systems. Music therapy interventions are based on active/receptive approaches (characterized by a relational or rehabilitative component) but also on music listening. Music-based interventions can be considered activities aimed at increasing the person's well-being. The objectives of making/listening to music are to improve the person's mood and motivation, promote socialization and stimulate sensory, motor and cognitive aspects. In particular, music listening effects concern structured symptoms and general well-being reducing anxiety and stress. New technologies, such as algorithmic music and machine learning techniques, can also help to develop therapeutic interventions with music and to bring art and science closer together, in the service of medicine, in clinical work and in research.
Treatment targets in SLE: remission and low disease activity state
Authors: Golder Vera , Tsang-A-Sjoe Michel W P
Published: July 2020

Treat-to-target strategies have changed the approach to management of many chronic conditions, with improvements in patient outcomes. The key to success of treat to target is the availability of validated treatment endpoints, which have been difficult to derive for SLE, a condition notorious for its heterogeneity. This review will focus on the development and validation of the definitions of remission in SLE framework and the lupus low disease activity state. Lupus low disease activity state is more attainable than remission, with a stepwise concentric relationship between the target states indicating increasing stringency. Both lupus low disease activity state and definitions of remission in SLE remission have been proven to be associated with reduction in disease flares, reduced risk of accrual of irreversible end organ damage, and improvement in patient reported outcomes. These endpoints have therefore provided the key for the development of a treat-to-target approach in clinical practice in SLE and for the design of future clinical trials.
Comparing two measures of sleep depth/intensity
Authors: Younes Magdy , Schweitzer Paula K , Griffin Kara S , Balshaw Robert , Walsh James K
Published: July 2020

Study Objectives

To compare delta spectral power (delta) and odds ratio product (ORP) as measures of sleep depth during sleep restriction with placebo or a drug that increases delta.

Methods

This is a secondary analysis of data from a study of 41 healthy participants randomized to receive placebo or gaboxadol 15 mg during sleep restriction. Participants underwent in-laboratory sleep studies on two baseline, four sleep restriction (5-h), and two recovery nights. Relation between delta or ORP and sleep depth was operationally defined as the degree of association of each metric to the probability of arousal or awakening occurring during the next 30 s (arousability).

Results

ORP values in wake, N1, N2, N3, and REM were significantly different. Delta differed between both N2 and N3 and other sleep stages but not between wake and N1 or N1 and REM. Epoch-by-epoch and individual correlations between ORP and delta power were modest or insignificant. The relation between ORP and arousability was linear across the entire ORP range. Delta also changed with arousability but only when delta values were less than 300 μV2. Receiver-operating-characteristic analysis found the ability to predict imminent arousal to be significantly greater with ORP than with log delta power for all experimental conditions. Changes in ORP, but not log delta, across the night correlated with next-day physiologic sleep tendency.

Conclusions

Compared to delta power, ORP is more discriminating among sleep stages, more sensitive to sleep restriction, and more closely associated with arousability. This evidence supports ORP as a measure of sleep depth/intensity.
Interpretive Principles in Reading the Right of Children to Free and Compulsory Education Act, 2009
Authors: Chandra Sushant
Published: July 2020

The Right of Children to Free and Compulsory Education Act, 2009 (hereinafter referred to as RTE Act) enacted by the Indian Parliament in 2009 has been a kernel of constitutional controversies. There are spate of controversies emerging from polemical provisions under the RTE Act. In this article, the rabid principle slating out free education for children for economically weaker section and disadvantaged category has been dissected in its design, content, function, and perception. The first part of the article explores different state-private welfare function models and locates the 25 per cent reservation clause under the gamut of one of its classifications. The second part of the article evaluates the Formalist and Realist arguments, and while mapping the role played by objective purpose of the education statute, it argues for the suitability of Holmesian approach to interpreting the 25 per cent reservation clause. In the backdrop of the debate between formal interpretation and Holmesian interpretation, the third part of the article sets out the approaches adopted by different High Courts in interpreting 25 per cent reservation clause and argues for adopting a coherent approach across different courts in India. The final part of the article concludes.
Acute and sub-chronic (28-day) oral toxicity profiles of newly synthesized prebiotic butyl-fructooligosaccharide in ICR mouse and Wistar rat models
Authors: Kang Sini , Johnston Tony V , Ku Seockmo , Ji Geun Eog
Published: July 2020

B-FOS (butyl-fructooligosaccharide) is a newly synthesized prebiotic molecule, formed by the combination of FOS and butyrate by ester bonds. B-FOS has been reported to have the potential prebiotic effect of promoting intestinal flora diversity and enhancing butyrate production. The aim of this study was to investigate the potential acute and sub-chronic toxicity of B-FOS in Institute of Cancer Research (ICR) mice and Wistar rats to verify its biosafety. ICR mice were administered a single oral gavage of B-FOS at doses of 0, 500, 1000, and 2000 mg/kg body weight and observed for signs of acute toxicity for 14 days. Sub-chronic toxicity was evaluated by repeated oral administration of B-FOS at 2000 mg/kg for 28 days, in accordance with Organization for Economic Co-operation and Development (OECD) protocol test numbers 420 and 407. No mortality or abnormal clinical signs were observed during the experimental periods after B-FOS administration. Furthermore, no significant changes in body weight, organ weight, serum biochemical parameters, or tissue histology were observed after animal sacrifice. These in vivo results indicate that B-FOS does not exert any acute or sub-chronic toxicity at a dose of 2000 mg/kg, and this novel molecule can be regarded as a safe prebiotic substance for use in the food and nutraceutical industries.
1-3HYPERTENSION IN PATIENTS WHO ADMITTED TO THE EMERGENCY UNIT OF THE INDONESIAN CHRISTIAN UNIVERSITY GENERAL HOSPITAL 2017
Authors: Suling Frits R.W.
Published: July 2020

Hypertension is a common risk factor for cardiovascular disease. Based on JNC VII, hypertension is defined as the condition of systolic blood pressure greater than or equal to 140 mmHg or diastolic blood pressure greater than or equal to 90 mmHg. In developed countries, the prevalence of hypertension in man 35.9%, woman 37.2%. According to Riskesdas 2013, the prevalence of hypertension in Indonesia at age ≥18 year equal to 25,8%. Only 36.8% detected by health workers, 63.2% of cases of hypertension in the community are undiagnosed. The prevalence of DM, hyperthyroidism and hypertension in women tends to be higher than in men.1 This research was conducted retrospectively. Based on the results of our research on patients entered the UKI General Hospital during January-November 2017, patients diagnosed with hypertension were 81 people. Patient with only hypertension-diagnosed were 49 people. Hypertension and CKD 7 people. Hypertension and DM 12 people. Hypertension with CHD 5 people, and Hypertension with Stroke 1 person. Patient with hypertension and CKD and DM were found 5 people. Hypertension with CKD and CHD 1 person, Hypertension with CKD and Stroke not founded. Hypertension and DM and CHD 1 person, Hypertension and DM and Stroke not founded. Hypertension with CHD and Stroke is also not founded.
3-2EXTRACRANIAL ARTERIAL PLAQUE CHARACTERISTICS IN ISCHEMIC STROKE PATIENTS AT DR. M.DJAMIL HOSPITAL 2019
Authors: Sutia Dedi , Indra Syarif , Busra Yoga Setia K Meldayeni
Published: July 2020

Introduction:

Atherosclerosis in carotid arteries cause more than 80% cerebral thromboembolism cases. One of the diagnostic modalities to evaluate the plaque's characteristics is using duplex carotid ultrasonography. In general, the risk of stroke depends on the degree of stenosis, surface, and morphology of formed plaque.

Objective:

This study aims to determine the characteristics of extracranial arterial plaque in ischemic stroke patients.

Method:

This study uses a descriptive design. The data was secondary data obtained from the Neurology Department of RSUP Dr. M. Djamil, Padang medical records from January to December 2019.

Results:

From 140 ischemic stroke patients who underwent duplex carotid ultrasonography, extracranial carotid artery stenosis was found in 30 patients (21%) consist of 17 males (56%). Most patients (80%) are in 45–65 years age group. The mean age is 46 years. Right carotid artery stenosis was found in 18 patients (60%) and left in 12 patients (40%). The degree of stenosis <50% and 50–70% were obtained in 12 patients (40%), respectively, and the degree of stenosis > 70% were obtained in 6 patients (20%). Based on plaque morphology, the soft plaque was found in 18 patients (60%), and a hard plaque was found in 12 patients (40%). Ulcerative plaques were obtained in 17 patients (57%) and non-ulserative in 13 patients (43%).

Conclusion:

Extracranial artery stenosis is more common in men with 45–65 years of group age. The location of stenosis is more often found in the right carotid artery. The most common degree of stenosis is <70%. Most of the plaque has soft plaque morphology, and the surface has of ulcerated plaque morphology.
3-7EFFECTIVENESS OF DEMONSTRATION COUNSELING METHOD ON KNOWLEDGE LEVEL REGARDING COMPLIANCE WITH DIET ON HYPERTENSION PATIENTS IN PUSKESMAS SUNGAI KAKAP, KUBU RAYA REGENCY, WEST KALIMANTAN
Authors: Islami Aditya , Nasution Bakrie Bayquni , Mustika Angnes Dera , Sonia Gatria , Purba Nur Harini
Published: July 2020

Background:

Hypertension is still a high cause of death and illness. The results of the 2018 Riskesdas study showed that there was an increase in the number of hypertension that remained permanently from 2013 to 2018. Hypertension was still ranked first in the highest number of non-communicable diseases in Sungai Kakap. The most common conventional education patterns used in Primary Health Care Facilities in the form of lecture methods are still seen to be ineffective in influencing the level of public knowledge of salt needs and other nutritional content as well as eating patterns suitable for hypertensive patients.

Methods:

This research is a quasi-experimental research design of One Group Pretest Posttest, the results of which will be analyzed descriptively and analytically. Samples were taken by purposive sampling totaling 32 people divided into two groups: the test group was given a conventional counseling material lecture method, and the test group was given counseling material with a demonstration method. Primary data were obtained from pretest and posttest using a questionnaire in hypertensive patients in the working area of Puskesmas Sungai Kakap. Data were analyzed using the unpaired T-test.

Result:

The mean post-test results in the conventional lecture method group were 69.37 ± 16.11 and there were no significant differences in the comparison between pre-test and post-test scores. The mean post-test results in the group with the demonstration method treatment were worth 85.00 ± 14.60 and there was a significant difference in the comparison between the pre-test and post-test scores in the group with the counseling treatment demonstration method where the post-test value was higher than the post-test. The mean post-test score of the group using the demonstration method was of higher significance statistically when compared to the group with the lecture method (Sig <0.05, 95% confidence level) with a value difference of 15.62.

Hypertension Diet Counseling with Demonstration Method is more effective compared to Conventional Counseling Lecture Method