bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical simulations of colliding jets in an external wind: application to 3C 75
Authors: Musoke G , Young A J , Molnar S M , Birkinshaw M 
Published: April 2020

ABSTRACT
The radio galaxy 3C 75 is remarkable because it contains a pair of radio-loud active galaxies, each of which produces a two-sided jet, with the jet beams appearing to collide and merge to the west of the galaxies. Motivated by 3C 75, we have conducted three-dimensional hydrodynamic simulations of jet collisions. We have extended previous studies by modelling the physical properties of the cluster atmosphere, including an external wind, and using realistic jet powers obtained from observational data. We are able to produce a morphology similar to that of 3C 75. The simulations imply that direct contact between the bulk jet flows on the west of the source is required to produce a morphology consistent with 3C 75. We quantify how the merging jets decelerate, how the wind deflects the jets and cocoons, the entrainment of intra-cluster material into the cocoons, the cocoon energetics, and how the jet interactions generate enstrophy. By comparing simulations of pairs of two-sided jets with those of single two-sided sources, we determine how the interaction between two bipolar jets changes their evolution. The unprecedented sensitivity and angular resolution of upcoming observatories will lead to the detection of many more complex sources at high redshift, where interacting jets are expected to be more numerous. The morphology of these complex sources can provide significant insight into the conditions in their environments.
Less noticeable shallow decay phase in early X-ray afterglows of GeV/TeV-detected gamma-ray bursts
Authors: Yamazaki Ryo , Sato Yuri , Sakamoto Takanori , Serino Motoko 
Published: April 2020

ABSTRACT
The nature of the shallow decay phase in the X-ray afterglow of the gamma-ray burst (GRB) is not yet clarified. We analyse the data of early X-ray afterglows of 26 GRBs triggered by Burst Alert Telescope onboard Neil Gehrels Swift Observatory and subsequently detected by Fermi Large Area Telescope (LAT) and/or Imaging Atmospheric Cherenkov Telescopes. It is found that nine events (including two out of three very-high-energy gamma-ray events) have no shallow decay phase and that their X-ray afterglow light curves are well described by single power-law model except for the jet break at later epoch. The rest are fitted by double power-law model and have a break in the early epoch (around ks), however, eight events (including a very-high-energy gamma-ray event) have the pre-break decay index larger than 0.7. We also analyse the data of well-sampled X-ray afterglows of GRBs without LAT detection and compare their decay properties with those of high-energy and very-high-energy gamma-ray events. It is found that for the GeV/TeV bursts, the fraction of events whose X-ray afterglows are described by single power law is significantly larger than those for non-GeV/TeV GRBs. Even if the GeV/TeV GRBs have shallow decay phase, their decay slope tends to be steeper than non-GeV/TeV bursts, that is, they have less noticeable shallow decay phase in the early X-ray afterglow. A possible interpretation along with the energy injection model is briefly discussed.
Analysis of the galaxy size versus stellar mass relation
Authors: Almeida J Sánchez 
Published: April 2020

Abstract
The scatter in the galaxy size versus stellar mass (M⋆) relation gets largely reduced when, rather than the half-mass radius Re, the size at a fixed surface density is used. Here we address why this happens. We show how a reduction is to be expected because any two galaxies with the same M⋆ have at least one radius with identical surface density, where the galaxies have identical size. However, the reason why the scatter is reduced to the observed level is not trivial, and we pin it down to the galaxy surface density profiles approximately following Sersic profiles with their Re and Sersic index (n) anti-correlated (i.e., given M⋆, n increases when Re decreases). Our analytical results describe very well the behavior of the observed galaxies as portrayed in the NASA Sloan Atlas (NSA), which contains more than half a million local objects with 7 &lt; log (M⋆/M⊙) &lt; 11.5. The comparison with NSA galaxies also allows us to find the optimal values for the mass surface density ($2.4_{-0.9}^{+1.3}\, M_\odot \, {\rm pc}^{-2}$) and surface brightness (r-band 24.7 ± 0.5 mag arcsec−2) that minimize the scatter, although the actual values depend somehow on the subset of NSA galaxies used for optimization. The physical reason for the existence of optimal values is unknown but, as Trujillo et al. (2020) point out, they are close to the gas surface density threshold to form stars and thus may trace the physical end of a galaxy. Our NSA-based size–mass relation agrees with theirs on the slope as well as on the magnitude of the scatter. As a by-product of the narrowness of the size–mass relation (only 0.06 dex), we propose to use the size of a galaxy to measure its stellar mass. In terms of observing time, it is not more demanding than the usual photometric techniques and may present practical advantages in particular cases.
A non-linear mathematical model for the X-ray variability classes of the microquasar GRS 1915+105 – I. Quiescent, spiking states, and quasi-periodic oscillations
Authors: Massaro E , Capitanio F , Feroci M , Mineo T , Ardito A , Ricciardi P 
Published: April 2020

ABSTRACT
The microquasar GRS 1915+105 is known to exhibit a very variable X-ray emission on different time-scales and patterns. We propose a system of two ordinary differential equations, adapted from the Hindmarsh–Rose model, with two dynamical variables x(t), y(t), and an input constant parameter J0, to which we added a random white noise, whose solutions for the x(t) variable reproduce consistently the X-ray light curves of several variability classes as well as the development of low-frequency quasi-periodic oscillations (QPO). We show that changing only the value of J0, the system moves from stable to unstable solutions and the resulting light curves reproduce those of the quiescent classes like ϕ and χ, the δ class and the spiking ρ class. Moreover, we found that increasing the values of J0 the system induces high-frequency oscillations that evolve into QPO when it moves into another stable region. This system of differential equations gives then a unified view of the variability of GRS 1915+105 in term of transitions between stable and unstable states driven by a single input function J0. We also present the results of a stability analysis of the equilibrium points and some considerations on the existence of periodic solutions.
A tale of two sites – I. Inferring the properties of minihalo-hosted galaxies from current observations
Authors: Qin Yuxiang , Mesinger Andrei , Park Jaehong , Greig Bradley , Muñoz Julian B 
Published: April 2020

ABSTRACT
The very first galaxies that started the cosmic dawn likely resided in so-called ‘minihaloes’, with masses of ∼105–$10^8{\, {\rm M}_\odot }$, accreting their gas from the intergalactic medium through H2 cooling. Such molecularly cooled galaxies (MCGs) mostly formed in pristine environments, hosted massive, metal-free stars, and were eventually sterilized by the build-up of a disassociating (Lyman–Werner; LW) background. Therefore, their properties might be very different from the galaxies we see in the later Universe. Although MCGs are probably too faint to be observed directly, we could nevertheless infer their properties from the imprint they leave in the cosmic 21-cm signal. Here we quantify this imprint by extending the public simulation code 21cmFAST to allow for a distinct population of MCGs. We allow MCGs to have different properties from other galaxies, including unique scaling relations for their stellar-to-halo mass ratios, ionizing escape fractions, and spectral energy distributions. We track inhomogeneous recombinations, disassociative LW feedback, and photoheating from reionization. After demonstrating how MCGs can shape the 21-cm signal, we explore to what extent current observations can already place constraints on their properties. The cosmic microwave background optical depth from Planck sets an upper limit on the product of the ionizing escape fraction and the stellar mass in MCGs. When including also the timing of the putative EDGES absorption signal, we find an additional strong degeneracy between the stellar mass and the X-ray luminosity of MCGs. If proven to be of cosmic origin, the timing of the EDGES signal would have been set by MCGs.
Mapping the relativistic electron gas temperature across the sky
Authors: Remazeilles Mathieu , Chluba Jens 
Published: April 2020

ABSTRACT
With increasing sensitivity, angular resolution, and frequency coverage, future cosmic microwave background (CMB) experiments like PICO will allow us to access new information about galaxy clusters through the relativistic thermal Sunyaev–Zeldovich (SZ) effect. We will be able to map the temperature of relativistic electrons across the entire sky, going well beyond a simple detection of the relativistic SZ effect by cluster stacking methods that currently define the state-of-the-art. Here, we propose a new map-based approach utilizing SZ-temperature moment expansion and constrained-ILC methods to extract electron gas temperature maps from foreground-obscured CMB data. This delivers a new independent map-based observable, the electron temperature power spectrum $T_{\rm e}^{yy}(\ell)$, which can be used to constrain cosmology in addition to the Compton-y power spectrum $C_\ell ^{yy}(\ell)$ . We find that PICO has the required sensitivity, resolution, and frequency coverage to accurately map the electron gas temperature of galaxy clusters across the full sky, covering a broad range of angular scales. Frequency coverage at $\nu \gtrsim 300\, {\rm GHz}$ plays an important role for extracting the relativistic SZ effect in the presence of foregrounds. For Coma, PICO will allow us to directly reconstruct the electron temperature profile using the relativistic SZ effect. Coma’s average electron temperature will be measured to 10σ significance after foreground removal using PICO. Low angular resolution CMB experiment like LiteBIRD could achieve 2σ to 3σ measurement of the electron temperature of this largest cluster. Our analysis highlights a new spectroscopic window into the thermodynamic properties of galaxy clusters and the diffuse electron gas at large angular scales.
Do nuclear rings in barred galaxies form at the shear minimum of the rotation curve?
Authors: Sormani Mattia C , Li Zhi 
Published: April 2020

ABSTRACT
It has been recently suggested that (i) nuclear rings in barred galaxies (including our own Milky Way) form at the radius where the shear parameter of the rotation curve reaches a minimum; and (ii) the acoustic instability of Montenegro et al. is responsible for driving the turbulence and angular momentum transport in the central regions of barred galaxies. Here, we test these suggestions by running simple hydrodynamical simulations in a logarithmic barred potential. Since the rotation curve of this potential is scale free, the shear minimum theory predicts that no ring should form. We find that in contrast to this prediction, a ring does form in the simulation, with morphology consistent with that of nuclear rings in real barred galaxies. This proves that the presence of a shear-minimum is not a necessary condition for the formation of a ring. We also find that perturbations that are predicted to be acoustically unstable wind up and eventually propagate off to infinity, so that the system is actually stable. We conclude that (i) the shear-minimum theory is an unlikely mechanism for the formation of nuclear rings in barred galaxies; and (ii) the acoustic instability is a spurious result and may not be able to drive turbulence in the interstellar medium, at least for the case without self-gravity. The question of the role of turbulent viscosity remains open.
Use of a human embryonic stem cell model to discover GABRP, WFDC2, VTCN1 and ACTC1 as markers of early first trimester human trophoblast
Authors: Karvas Rowan M , McInturf Samuel , Zhou Jie , Ezashi Toshihiko , Schust Danny J , Roberts R Michael , Schulz Laura C 
Published: April 2020

Abstract
Human placental development during early pregnancy is poorly understood. Many conceptuses are lost at this stage. It is thought that preeclampsia, intrauterine growth restriction and other placental syndromes that manifest later in pregnancy may originate early in placentation. Thus, there is a need for models of early human placental development. Treating human embryonic stem cells (hESCs) with BMP4 (bone morphogenic protein 4) plus A83-01 (ACTIVIN/NODAL signaling inhibitor) and PD173074 (fibroblast growth factor 2 or FGF2 signaling inhibitor) (BAP conditions) induces differentiation to the trophoblast lineage (hESCBAP), but it is not clear which stage of trophoblast differentiation these cells resemble. Here, comparison of the hESCBAP transcriptome to those of trophoblasts from human blastocysts, trophoblast stem cells and placentas collected in the first–third trimester of pregnancy by principal component analysis suggests that hESC after 8 days BAP treatment most resemble first trimester syncytiotrophoblasts. To further test this hypothesis, transcripts were identified that are expressed in hESCBAP but not in cultures of trophoblasts isolated from term placentas. Proteins encoded by four genes, GABRP (gamma-aminobutyric acid type A receptor subunit Pi), WFDC2 (WAP four-disulfide core domain 2), VTCN1 (V-set domain containing T-cell activation inhibitor 1) and ACTC1 (actin alpha cardiac muscle 1), immunolocalized to placentas at 4–9 weeks gestation, and their expression declined with gestational age (R2 = 0.61–0.83). None are present at term. Expression was largely localized to syncytiotrophoblast of both hESCBAP cells and placental material from early pregnancy. WFDC2, VTCN1 and ACTC1 have not previously been described in placenta. These results support the hypothesis that hESCBAP represent human trophoblast analogous to that of early first trimester and are a tool for discovery of factors important to this stage of placentation.
DIS3L2 and LSm proteins are involved in the surveillance of Sm ring-deficient snRNAs
Authors: Roithová Adriana , Feketová Zuzana , Vaňáčová Štěpánka , Staněk David 
Published: April 2020

AbstractSpliceosomal small nuclear ribonucleoprotein particles (snRNPs) undergo a complex maturation pathway containing multiple steps in the nucleus and in the cytoplasm. snRNP biogenesis is strictly proofread and several quality control checkpoints are placed along the pathway. Here, we analyzed the fate of small nuclear RNAs (snRNAs) that are unable to acquire a ring of Sm proteins. We showed that snRNAs lacking the Sm ring are unstable and accumulate in P-bodies in an LSm1-dependent manner. We further provide evidence that defective snRNAs without the Sm binding site are uridylated at the 3′ end and associate with DIS3L2 3′→5′ exoribonuclease and LSm proteins. Finally, inhibition of 5′→3′ exoribonuclease XRN1 increases association of ΔSm snRNAs with DIS3L2, which indicates competition and compensation between these two degradation enzymes. Together, we provide evidence that defective snRNAs without the Sm ring are uridylated and degraded by alternative pathways involving either DIS3L2 or LSm proteins and XRN1.
GSK-3 is an RNA polymerase II phospho-CTD kinase
Authors: Nieto Moreno Nicolás , Villafañez Florencia , Giono Luciana E , Cuenca Carmen , Soria Gastón , Muñoz Manuel J , Kornblihtt Alberto R 
Published: April 2020

Abstract
We have previously found that UV-induced DNA damage causes hyperphosphorylation of the carboxy terminal domain (CTD) of RNA polymerase II (RNAPII), inhibition of transcriptional elongation and changes in alternative splicing (AS) due to kinetic coupling between transcription and splicing. In an unbiased search for protein kinases involved in the AS response to DNA damage, we have identified glycogen synthase kinase 3 (GSK-3) as an unforeseen participant. Unlike Cdk9 inhibition, GSK-3 inhibition only prevents CTD hyperphosphorylation triggered by UV but not basal phosphorylation. This effect is not due to differential degradation of the phospho-CTD isoforms and can be reproduced, at the AS level, by overexpression of a kinase-dead GSK-3 dominant negative mutant. GSK-3 inhibition abrogates both the reduction in RNAPII elongation and changes in AS elicited by UV. We show that GSK-3 phosphorylates the CTD in vitro, but preferentially when the substrate is previously phosphorylated, consistently with the requirement of a priming phosphorylation reported for GSK-3 efficacy. In line with a role for GSK-3 in the response to DNA damage, GSK-3 inhibition prevents UV-induced apoptosis. In summary, we uncover a novel role for a widely studied kinase in key steps of eukaryotic transcription and pre-mRNA processing.
Metabolic reprogramming in cancer: the bridge that connects intracellular stresses and cancer behaviors
Authors: Zhou Yi , Sun Huiyan , Xu Ying 
Published: April 2020

Summary
Extensive changes in cellular metabolisms have been observed in cancer. They are probably induced by the same intracellular stressor, persistent off-balance in intracellular pH across possibly all adult cancers. It is these altered metabolisms that gives rise to a variety of cancerous behaviors such as continuous cell division, metastasis and drug resistance.
Selective electrochemical production of hydrogen peroxide at zigzag edges of exfoliated molybdenum telluride nanoflakes
Authors: Zhao Xuan , Wang Yu , Da Yunli , Wang Xinxia , Wang Tingting , Xu Mingquan , He Xiaoyun , Zhou Wu , Li Yafei , Coleman Jonathan N , Li Yanguang 
Published: April 2020

Abstract
The two-electron reduction of molecular oxygen represents an effective strategy to enable the green, mild and on-demand synthesis of hydrogen peroxide. Its practical viability, however, hinges on the development of advanced electrocatalysts, preferably composed of non-precious elements, to selectively expedite this reaction, particularly in acidic medium. Our study here introduces 2H-MoTe2 for the first time as the efficient non-precious-metal-based electrocatalyst for the electrochemical production of hydrogen peroxide in acids. We show that exfoliated 2H-MoTe2 nanoflakes have high activity (onset overpotential ∼140 mV and large mass activity of 27 A g−1 at 0.4 V versus reversible hydrogen electrode), great selectivity (H2O2 percentage up to 93%) and decent stability in 0.5 M H2SO4. Theoretical simulations evidence that the high activity and selectivity of 2H-MoTe2 arise from the proper binding energies of HOO* and O* at its zigzag edges that jointly favor the two-electron reduction instead of the four-electron reduction of molecular oxygen.
Seizures in an Immunocompetent Adult From Treatment of Latent Tuberculosis Infection: Is Isoniazid to Blame?
Authors: Navalkele Bhagyashri , Bueno Rios Maria X , Wofford John D , Kumar Vijay , Webb Risa M 
Published: April 2020

Abstract
Isoniazid-induced seizures are a rare adverse reaction especially in immunocompetent adults. We report a case of a healthy man with seizures shortly after ingestion of his first therapeutic dose of isoniazid with rifapentine therapy for treatment of latent tuberculosis infection. Only 6 other similar cases are reported in the literature.
Regicide and Redemptive Violence in the French Revolution
Authors: Duong Kevin 
Published: April 2020

Abstract
This chapter describes how Jacobins crafted a new language of violence during the trial and execution of Louis XVI in the French Revolution: the language of redemptive violence. The execution of the king served as a founding act of French republican democracy. It was also a scene of irregular justice: no legal warrants or procedural precedents existed for bringing a king to justice before the law. Regicide as redemptive violence helped bypass that obstacle. Although redemptive violence had roots in prerevolutionary notions of penal justice and social cohesion, its philosophical ambitions were revolutionary and modern. Analyzing that language illuminates how republican democracy weaponized a distinctive ideology of extralegal violence at its origins. It also helps explain redemptive violence’s enduring appeal during and after the French Revolution.
From Glory to Total War in Algeria
Authors: Duong Kevin 
Published: April 2020

Abstract
This chapter analyzes the relationship between Tocqueville’s passion for glory and his endorsement of total war in Algeria. It is now commonplace to acknowledge Alexis de Tocqueville’s support for Algerian colonization. Less well understood, however, is why he also endorsed the French strategy of “total war” in the regency. How was Tocqueville’s liberalism linked to the specific shape of violence in Algeria? This chapter situates Tocqueville’s Algerian writings in the intersecting intellectual contexts of the 1840s to argue that his apologies for total war were shaped by the lingering legacies of revolutionary republicanism and Bonapartism which defined glory in terms of national defense. By tethering modern liberty to this conception of glory, Tocqueville provided resources for rationalizing settlerism’s exterminationist violence.
Redemptive Violence on the Eve of the Great War
Authors: Duong Kevin 
Published: April 2020

Abstract
This chapter studies how an image of irrationalist redemptive violence saturated French intellectual culture on the eve of the First World War. It links the proliferation of that image of violence to the popularity of Henri Bergson. It draws attention to the way his philosophy was adapted into a political theory of decadence and degeneration across the political spectrum after 1900. The chapter highlights the writing of Georges Sorel because a conceptual reconstruction of his Reflections on Violence dramatizes how so many French thinkers could link voluntaristic violence with moral regeneration. It concludes by describing the nationalistic fate of Sorel’s argument as it travelled in and beyond France.
Life After Deployment
Authors: Yarvis Jeffrey S. , Figley Charles R. 
Published: April 2020

Abstract
This chapter continues to prepare the reader to understand and appreciate the garrison duties of combat social workers (CSWs) and their day-to-day duties. Military social worker duties are similar to those within U.S. Veterans Administration and other institutions: administration, supervision, and direct practice. But a very special job of social workers within the military, including but not limited to CSWs, is to care for those who were deployed and their families. This includes services for combat social workers, as the authors note. This, at times, is challenging for CSWs who must not only care for themselves but for many clients they live near.
Dark Mornings to New Beginnings
Authors: Meshad Shad 
Published: April 2020

Abstract
This chapter discusses the experiences of a combat social worker who was wounded in combat and survived to go on to be a trail blazer as a Veteran Affairs (VA) clinical social worker. He describes how he was hired in 1971 to help the West Los Angeles VA Medical Center to organize an outreach program to Vietnam veterans who refused to seek help from the VA because of their experiences within the military. The author presents the vet-to-vet rap group model and the Vet Center project, where he helped to identify resources and guide vets and their families to what they need. The author describes his successful career as a social activist and veteran advocate through his LA-based National Veterans Foundation.