bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Infrared Emission and Vigorous Star Formation of Low-redshift Quasars
Authors: Xie Yanxia , Ho Luis C. , Zhuang Ming-Yang , Shangguan Jinyi 
Published: April 2021

Abstract
The star formation activity of the host galaxies of active galactic nuclei provides valuable insights into the complex interconnections between black hole growth and galaxy evolution. A major obstacle arises from the difficulty of estimating accurate star formation rates (SFRs) in the presence of a strong active galactic nucleus. Analyzing the 1–500 μm spectral energy distributions and high-resolution mid-infrared spectra of low-redshift (z < 0.5) Palomar–Green quasars with bolometric luminosity of ∼1044.5–1047.5 erg s−1, we find, from comparison with an independent SFR indicator based on [Ne II] 12.81 μm and [Ne III] 15.56 μm, that the torus-subtracted, total infrared (8–1000 μm) emission yields robust SFRs in the range of ∼1–250 M
⊙ yr−1. Combined with available stellar mass estimates, the vast majority (∼75%–90%) of the quasars lie on or above the main sequence of local star-forming galaxies, including a significant fraction (∼50%–70%) that would qualify as starburst systems. This is further supported by the high star formation efficiencies derived from the gas content inferred from the dust masses. Inspection of high-resolution Hubble Space Telescope images reveals a wide diversity of morphological types, including a number of starbursting hosts that have not experienced significant recent dynamical perturbations. The origin of the high star formation efficiency is unknown.
Classification of Magnetohydrodynamic Simulations Using Wavelet Scattering Transforms
Authors: Saydjari Andrew K. , Portillo Stephen K. N. , Slepian Zachary , Kahraman Sule , Burkhart Blakesley , Finkbeiner Douglas P. 
Published: April 2021

Abstract
The complex interplay of magnetohydrodynamics, gravity, and supersonic turbulence in the interstellar medium (ISM) introduces a non-Gaussian structure that can complicate a comparison between theory and observation. In this paper, we show that the wavelet scattering transform (WST), in combination with linear discriminant analysis (LDA), is sensitive to non-Gaussian structure in 2D ISM dust maps. WST-LDA classifies magnetohydrodynamic (MHD) turbulence simulations with up to a 97% true positive rate in our testbed of 8 simulations with varying sonic and Alfvénic Mach numbers. We present a side-by-side comparison with two other methods for non-Gaussian characterization, the reduced wavelet scattering transform (RWST) and the three-point correlation function (3PCF). We also demonstrate the 3D-WST-LDA, and apply it to the classification of density fields in position–position–velocity (PPV) space, where density correlations can be studied using velocity coherence as a proxy. WST-LDA is robust to common observational artifacts, such as striping and missing data, while also being sensitive enough to extract the net magnetic field direction for sub-Alfvénic turbulent density fields. We include a brief analysis of the effect of point-spread functions and image pixelization on 2D-WST-LDA applied to density fields, which informs the future goal of applying WST-LDA to 2D or 3D all-sky dust maps to extract hydrodynamic parameters of interest.
Galactic Cosmic Rays, Cosmic-Ray Variations, and Cosmogenic Nuclides in Meteorites
Authors: Leya Ingo , Hirtz Jason , David Jean-Christophe 
Published: April 2021

Abstract
We present a new generation of model calculations for cosmogenic production rates in various types of solar system bodies. The model is based on the spectra for primary and secondary particles calculated using the INCL++6 code, which is the most reliable and most sophisticated code available for spallation reactions. Thanks to the recent improvements (extending the code to lower and higher energies and considering light charged particles as ejectiles and projectiles), we can for the first time directly consider primary and secondary Galactic α particles. We calculate production rates for 22Na, 10Be, and 26Al in an L-chondrite with a radius of 45 cm and in the Apollo 15 drill core, and we determine the long-term average Galactic cosmic-ray (GCR) spectrum (represented by the solar modulation potential Φ) in the meteoroid orbits at ∼3 au of Φ = 600 MV and at 1 au, i.e., for Earth and Moon of Φ = 660 MV. From this, we calculate a long-term average GCR gradient in the inner solar system of ∼5% au−1. Finally, we discuss the possibility of studying temporal GCR variations and meteoroid orbits using production rate ratios of short- and long-lived radionuclides.
A Machine-learning Approach to Integral Field Unit Spectroscopy Observations. II. H ii Region Line Ratios
Authors: Rhea Carter , Rousseau-Nepton Laurie , Prunet Simon , Prasow-Émond Myriam , Hlavacek-Larrondo Julie , Asari Natalia Vale , Grasha Kathryn , Perreault-Levasseur Laurence 
Published: April 2021

Abstract
In the first paper of this series, we demonstrated that neural networks can robustly and efficiently estimate kinematic parameters for optical emission-line spectra taken by SITELLE at the Canada–France–Hawaii Telescope. This paper expands upon this notion by developing an artificial neural network to estimate the line ratios of strong emission lines present in the SN1, SN2, and SN3 filters of SITELLE. We construct a set of 50,000 synthetic spectra using line ratios taken from the Mexican Million Model database replicating H
ii regions. Residual analysis of the network on the test set reveals the network’s ability to apply tight constraints to the line ratios. We verified the network’s efficacy by constructing an activation map, checking the [N
ii] doublet fixed ratio, and applying a standard k-fold cross-correlation. Additionally, we apply the network to SITELLE observations of M33; the residuals between the algorithm’s estimates and values calculated using standard fitting methods show general agreement. Moreover, the neural network reduces the computational costs by two orders of magnitude. Although standard fitting routines do consistently well depending on the signal-to-noise ratio of the spectral features, the neural network can also excels at predictions in the low signal-to-noise regime within the controlled environment of the training set as well as on observed data when the source spectral properties are well constrained by models. These results reinforce the power of machine learning in spectral analysis.
The Effect of Warm Dark Matter on Early Star Formation Histories of Massive Galaxies: Predictions from the CROC Simulations
Authors: Esmerian Clarke J. , Gnedin Nickolay Y. 
Published: April 2021

Abstract
Several massive (M
* > 108
M
⊙), high-redshift (z = 8–10) galaxies have recently been discovered to contain stars with ages of several hundred million years, pushing the onset of star formation in these galaxies back to z ∼ 15. The very existence of stars formed so early may serve as a test for cosmological models with suppressed small-scale power (and, hence, late formation of cosmic structure). We explore the ages of the oldest stars in numerical simulations from the Cosmic Reionization On Computers project with cold dark matter (CDM) and two warm dark matter (WDM) cosmologies with 3 and 6 keV particles. There are statistically significant differences of ∼5 Myr between average stellar ages of massive galaxies in CDM and 3 keV WDM, while CDM and 6 keV WDM are statistically indistinguishable. Even this 5 Myr difference, however, is much less than current observational uncertainties on the stellar population properties of high-redshift galaxies. The age distributions of all galaxies in all cosmologies fail to produce a substantial Balmer break, although uncertainties in dust attenuation are a potentially significant factor. Finally, we assess the convergence of our simulation predictions and find that the systematic uncertainties on individual galaxy properties are comparable to the differences between cosmologies, suggesting these differences may not be numerically robust.
Shock Breakout in Dense Circumstellar Material with Application to PS1-13arp
Authors: Haynie Annastasia , Piro Anthony L. 
Published: April 2021

Abstract
Shock breakout (SBO), the first expected electromagnetic signature of a supernova (SN), can be an important probe of the progenitors of these explosions. Unfortunately, SBO is difficult to capture with current surveys due to its brief timescale (≲1 hr). However, SBO may be lengthened when dense circumstellar material (CSM) is present. Indeed, recent photometric modeling studies of SNe, as well as early spectroscopy, suggest that such dense CSM may be present more often than previously expected. If true, this should also affect the features of SBO. We present an exploration of the impact of such CSM interaction on the SBO width and luminosity using both analytic and numerical modeling, where we parameterize the CSM as a steady-state wind. We then compare this modeling to PS1-13arp, an SN that showed an early UV excess that has been argued to be SBO in dense CSM. We find PS1-13arp is well fit with a wind of mass ∼0.08 M
⊙ and radius ∼1900 R
⊙, parameters which are similar to, if not slightly less massive than, what have been inferred for Type II SNe using photometric modeling. This similarity suggests that future SBO observations of SNe II may be easier to obtain than previously appreciated.
De nouveau, un homme
Authors: Farhi William 
Published: April 2021

La culture juive, comme la littérature rabbinique, véhiculent des conceptions alternatives de l’homme, qui font office de « masculinités de résistance » face aux modèles occidentaux. Or l’État d’Israël paraît rompre avec cet héritage pour embrasser des idéaux conventionnels de virilité, marqués par trois figures symboliques : le soldat, le pionnier et le chef.
L’apatridie rrom en Europe
Authors: de Verneuil Maylis 
Published: April 2021

Aujourd’hui, on compte encore 15000 personnes dépourvues de documents d’identité et de toute forme de protection étatique en Europe. Si la dissolution de l’Union soviétique et de la Yougoslavie, et l’attribution partielle de nouvelles nationalités par les États successeurs aux populations résidant sur leur territoire peuvent expliquer l’existence d’apatrides sur le continent, le problème persiste au sein de la communauté rrom en raison des discriminations qu’elle subit.
La mer montera, des États disparaîtront…
Authors: Piguet Étienne 
Published: April 2021

Est-ce qu’un État submergé cesse d’être un État ? Dans ce cas, à quel moment ses resssortissant·es risquent-ils ou elles l’apatridie ? Ces questions n’ont rien de rhétorique dans un contexte où le réchauffement climatique – induit par l’activité humaine – entraîne l’élévation du niveau des mers. Plusieurs États insulaires sont d’ores et déjà concernés. L’apatridie climatique n’est toujours pas reconnue dans le droit international et aucune solution n’a encore émergé quant à l’installation – spatiale et juridique – des populations menacées.
Change and Continuity in Economic Methodology and Philosophy of Economics
Authors: Davis John B. 
Published: April 2021

Cet article présente mes réflexions en leur état au début de l’année 2020 quant à la situation de la méthodologie économique et de la philosophie de l’économie (ou philosophie économique), après quinze années passées à la co-direction (avec Wade Hands) du Journal of Economic Methodology . J’y constate les changements des méta-champs de recherche que sont la méthodologie et la philosophie de l’économie, depuis leur surgissement comme sous-domaines au sein des sciences économiques durant les années 1980. En usant d’une analyse qui prend en considération l’évolution technologique, j’y distingue deux scenarii envisageables pour l’avenir du champ, en rapport aux facteurs de l’environnement l’impactant, et quant à l’influence de la spécialisation croissante de la recherche, à la fois sur ce champ même et sur les sciences économiques ; j’élabore enfin une argumentation transdisciplinaire touchant son évolution future vers la diversité et la pluralité dans la recherche académique.
Glycolipid-Containing Nanoparticle Vaccine Engages Invariant NKT Cells to Enhance Humoral Protection against Systemic Bacterial Infection but Abrogates T-Independent Vaccine Responses
Authors: Shute Travis , Amiel Eyal , Alam Noran , Yates Jennifer L. , Mohrs Katya , Dudley Elizabeth , Salas Briana , Mesa Chloe , Serrata Adriana , Angel Daniel , Vincent Brandy K. , Weyers Amanda , Lanthier Paula A. , Vomhof-Dekrey Emilie , Fromme Rachel , Laughlin Mitchell , Durham Olivia , Miao Jianjun , Shipp Devon , Linhardt Robert J. , Nash Kelly , Leadbetter Elizabeth A. 
Published: April 2021

Abstract
CD4+ T cells enable the critical B cell humoral immune protection afforded by most effective vaccines. We and others have recently identified an alternative source of help for B cells in mice, invariant NK T (iNKT) cells. iNKT cells are innate glycolipid-specific T cells restricted to the nonpolymorphic Ag-presenting molecule CD1d. As such, iNKT cells respond to glycolipids equally well in all people, making them an appealing adjuvant for universal vaccines. We tested the potential for the iNKT glycolipid agonist, α-galactosylceramide (αGC), to serve as an adjuvant for a known human protective epitope by creating a nanoparticle that delivers αGC plus antigenic polysaccharides from Streptococcus pneumoniae. αGC-embedded nanoparticles activate murine iNKT cells and B cells in vitro and in vivo, facilitate significant dose sparing, and avoid iNKT anergy. Nanoparticles containing αGC plus S. pneumoniae polysaccharides elicits robust IgM and IgG in vivo and protect mice against lethal systemic S. pneumoniae. However, codelivery of αGC via nanoparticles actually eliminated Ab protection elicited by a T-independent S. pneumoniae vaccine. This is consistent with previous studies demonstrating iNKT cell help for B cells following acute activation, but negative regulation of B cells during chronic inflammation. αGC-containing nanoparticles represent a viable platform for broadly efficacious vaccines against deadly human pathogens, but their potential for eliminating B cells under certain conditions suggests further clarity on iNKT cell interactions with B cells is warranted.
Long-Term Immunogenicity of Live Oral Cholera Vaccine CVD 103-HgR in Adolescents Aged 12–17 Years in the United States
Authors: McCarty James M. , Cassie David , Bedell Lisa , Lock Michael D. , Bennett Sean 
Published: April 2021

ABSTRACTAs part of a phase 4, randomized, double-blind, placebo-controlled trial to assess the immunogenicity and safety of PXVX0200 in children and adolescents aged 2–17 years, a subset of 73 adolescent subjects aged 12–17 years was followed for 2 years after vaccination and had blood collected for antibody assays on days 1, 11, 29, 91, 181, 365, 547, and 730. Endpoints included serum vibriocidal antibody (SVA) seroconversion, defined as a 4-fold or greater rise in antibody titer over baseline; geometric mean titers (GMTs); and geometric mean fold increase (GMFI) over baseline. Serum vibriocidal antibody seroconversion persisted in most subjects, with a rate of 64.5% noted at day 730. Geometric mean titers and GMFI both peaked at day 11 and remained greater than baseline at all time points, including day 730. Vaccination with PXVX0200 produces an immune response which persists for at least 2 years in adolescents aged 12–17 years.
Empirical Assessment of Missing Link in Agricultural Technology Development and Transfer Nexus in Nigeria
Authors: Ogunjimi Sunday I , Ojo Toyin F , Obabire Ibikunle E , Alabi Olajumoke O 
Published: April 2021

Governments and Non-Governmental Organisation (NGOs) focussed on the funding of research but neglect a very crucial issue of the transfer of technologies. Unfortunately, most of these technologies invented end up on bookshelves which might be as a result of missing linkage between the researchers, extension organizations and farmers. Therefore, the study focussed on factors associated with the missing link among researchers, extension workers and farmers in technology development and transfer. The study was carried out in the south-western part of Nigeria. The study employed the use of an interview schedule for farmers and questionnaire for extension personnel and researchers. A simple random sampling technique was used to select 398 respondents which include 80 researchers, 85 extension agents and 233 farmers.Data collected were analysed with descriptive statistics and correlation coefficient. The findings revealed that most (61%) of the selected technologies developed by research institutions were not known to the farmers. About 21% out of 39% of farmers that were aware of the technologies were still using it while 18% had discontinued the usage. Factors associated with research-extension-farmers missing link include package of recommendations not suitable for farmers (researcher 95.7%, extension agents 84.3% and farmers 95.1%); time lag between the availability of research findings and their application by the farmer (research (64.2%) extension workers (73.2%) and farmers (80%)), wages and salary differential (researchers (65.4%) and extension workers (78.3%)) and inadequate funds (researcher 90.4% and extension workers (95.3%)). The linkage strength could be influenced by the personal and psychological factors of personnel involved in research and dissemination. The gap that exists between the technologies invented and those that have been accepted by farmers has to be bridged by developing stronger links between researchers, extension personnel and the farmers by government agencies. Keywords— Extension workers, farmers, linkage, researchers, research development, technology transfer.
Influence of Particle Size and Particle Range Distribution on the Microstructure of Al–Mg–Si/PKSA Composite for Amateur Solid Rocket Chamber
Authors: Oyedeji Elijah O , Dauda Muhammed , Yaro Shehu A , Abdulwahab Malik 
Published: April 2021

The study discusses an overview of small rocket program, development and characterization of locally sourced material at low cost. The aim is to enable the construction of small sounding rocket components for experimental purposes in Nigeria. This paper proposes the utilization of palm kernel shell ash as filler materials in the development, characterization and production of composite material to construct prototype reusable chamber and accessories that will enable it possible for small scientific experiments. To achieve this, particle size and particle range distribution on the microstructure, texture, and mechanical properties of (Al–Mg–Si)/PKSA composites developed by powder metallurgy method were investigated. The access in the 6xxx series of aluminum-magnesium-silicon alloy was investigated for this reason. ImageJ software was used to do particle size analysis professionally and the software was used to calculate the area, mean, standard deviation (SD) and the pixel values. The particle size distribution of big constituent (densification or rather densified solids) particles and small dispersoids possess a finer and slightly elongated grain structure when compared with the unreinforced alloy. The results of the XRD and XRF of all the samples considered showed that Al2O3, SiO2, Mn2O3 and MgO phases were common to all. These hard phases are considered to be responsible for improved mechanical properties and resistance of the composite, while the SEM result showed that the reinforcement was uniformly distributed which further improves the mechanical property of the composite.Keywords: Microstructure, Composite, Rocket, Palm Kernel
Adaptive Power Control with Selection Combiner over Nakagami-m Fading Channel
Authors: Abolade Robert O , Oyedokun O O , Ojo Samson I , Adeyemo Zachaeus K , Ojerinde I A 
Published: April 2021

Acceptable Quality of Service (QoS) is of paramount importance in wireless communication system. However, QoS is affected by multipath propagation resulting in unreliable reception. Selection Combiner (SC) which is one of the techniques previously used to solve this problem is associated with poor performance due to fixed power level used in the technique. Hence, in this paper, an Adaptive Power Control (APC) technique using SC with a closed form expression over Nakagami-m Fading Channel is proposed. APC technique is developed using fixed power SC and Link Adaptation Algorithm (LAA). Ten thousand (10,000) bits are randomly generated and modulated using Quadrature Amplitude Modulation (QAM) scheme. The modulated signal is passed through the Square Root Raised Cosine (SRRC) filter for suitable transmission over the Nakagami-m fading channel. The faded signals at varying paths ‘L’ (2, 3, 4) are selected by Conventional Selection Combining (CSC) to instruct the transmitter for adjustment of power level based on the value of the received signal through LAA. Mathematical expression for the received signal using Probability Density Function (PDF) of Nakagami-m Fading Channel at varying paths is derived. The APC technique is simulated using MATLAB software and evaluated using Signal to Noise Ratio (SNR), Outage Probability (OP) and Bit Error Rate (BER) to determine the performance of the proposed technique. OP values of 0.0969 and 0.1069 are obtained for APC and CSC, respectively, at SNR of 6 dB with L of 4, while BER values of 0.0052 and 0.2599 are obtained for APC and CSC, respectively. The percentage reduction in OP and BER are 29.79% and 54.43%, respectively. The results obtained show that APC gives lower OP and BER values with increase in SNR when compared with fixed power SC due to self-adjustment of the allocated power. Therefore, the APC technique proposed can be used to enhance the performance of wireless communication systems. Keywords— Adaptive Power Control (APC), Selection Combiner (SC), Link Adaptation Algorithm (LAA), Bit Error Rate (BER), Outage Probability (OP), Probability Density Function (PDF) and Diversity Combiner (DC).
A Review on the Detection of Offensive Content in Social Media Platforms
Authors: Akinboro Solomon , Adebusoye Oluwadamilola , Onamade Akintoye 
Published: April 2021

Offensive content refers to messages which are socially unacceptable including vulgar or derogatory messages. As the use of social media increases worldwide, social media administrators are faced with the challenges of tackling the inclusion of offensive content, to ensure clean and non-abusive or offensive conversations on the platforms they provide. This work organizes and describes techniques used for the automated detection of offensive languages in social media content in recent times, providing a structured overview of previous approaches, including algorithms, methods and main features used. Selection was from peer-reviewed articles on Google scholar. Search terms include: Profane words, natural language processing, multilingual context, hybrid methods for detecting profane words and deep learning approach for detecting profane words. Exclusions were made based on some criteria. Initial search returned 203 of which only 40 studies met the inclusion criteria; 6 were on natural language processing, 6 studies were on Deep learning approaches, 5 reports analysed hybrid approaches, multi-level classification/multi-lingual classification appear in 13 reports while 10 reports were on other related methods.The limitations of previous efforts to tackle the challenges with regards to the detection of offensive contents are highlighted to aid future research in this area. Keywords— algorithm, offensive content, profane words, social media, texts