bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonlinear Color–Metallicity Relations of Globular Clusters. IX. Different Radial Number Density Profiles between Blue and Red Clusters
Authors: Lee Sang-Yoon , Chung Chul , Yoon Suk-Jin 
Published: December 2020

Abstract
The optical colors of globular clusters (GCs) in most large early-type galaxies are bimodal. Blue and red GCs show a sharp difference in the radial profile of their surface number density in the sense that red GCs are more centrally concentrated than blue GCs. An instant interpretation is that there exist two distinct GC subsystems having different radial distributions. This view, however, was challenged by a scenario in which, due to the nonlinear nature of the GC metallicity-to-color transformation for old (≳10 Gyr) GCs, a broad unimodal metallicity spread can exhibit a bimodal color distribution. Here we show, by simulating the radial trends in the GC color distributions of the four nearby giant elliptical galaxies (M87, M49, M60, and NGC 1399), that the difference in the radial profile between blue and red GCs stems naturally from the metallicity-to-color nonlinearity plus the well-known radial metallicity gradient of GC systems. The model suggests no or little radial variation in GC age even out to ∼20 R
eff. Our results provide a simpler solution to the distinct radial profiles of blue and red GCs that does not necessarily invoke the presence of two GC subsystems and further fortify the nonlinearity scenario for the GC color bimodality phenomenon.
Probing Jet Launching in Neutron Star X-Ray Binaries: The Variable and Polarized Jet of SAX J1808.4–3658
Authors: Baglio M. C. , Russell D. M. , Crespi S. , Covino S. , Johar A. , Homan J. , Bramich D. M. , Saikia P. , Campana S. , D’Avanzo P. , Fender R. P. , Goldoni P. , Goodwin A. J. , Lewis F. , Masetti N. , Zanon A. Miraval , Motta S. E. , Muñoz-Darias T. , Shahbaz T. 
Published: December 2020

Abstract
We report on an optical photometric and polarimetric campaign on the accreting millisecond X-ray pulsar (AMXP) SAX J1808.4–3658 during its 2019 outburst. The emergence of a low-frequency excess in the spectral energy distribution in the form of a red excess above the disk spectrum (seen most prominently in the z, i, and R bands) is observed as the outburst evolves. This is indicative of optically thin synchrotron emission due to a jet, as seen previously in this source and in other AMXPs during outburst. At the end of the outburst decay, the source enters a reflaring state. The low-frequency excess is still observed during the reflares. Our optical (BVRI) polarimetric campaign shows variable linear polarization (LP) throughout the outburst. We show that this is intrinsic to the source, with low-level but significant detections (0.2%–2%) in all bands. The LP spectrum is red during both the main outburst and the reflaring state, favoring a jet origin for this variable polarization over other interpretations, such as Thomson scattering with free electrons from the disk or the propelled matter. During the reflaring state, a few episodes with stronger LP levels (1%–2%) are observed. The low-level, variable LP is suggestive of strongly tangled magnetic fields near the base of the jet. These results clearly demonstrate how polarimetry is a powerful tool for probing the magnetic field structure in X-ray binary jets, as for active galactic nuclei jets.
Long-lived Eccentric Modes in Circumbinary Disks
Authors: Muñoz Diego J. , Lithwick Yoram 
Published: December 2020

Abstract
Hydrodynamical simulations show that circumbinary disks become eccentric, even when the binary is circular. Here we demonstrate that, in steady state, the disk’s eccentricity behaves as a long-lived free mode trapped by turning points that naturally arise from a continuously truncated density profile. Consequently, both the disk’s precession rate and eccentricity profile may be calculated via the simple linear theory for perturbed pressure-supported disks. By formulating and solving the linear theory, we find that (i) surprisingly, the precession rate is roughly determined by the binary’s quadrupole, even when the quadrupole is very weak relative to pressure; (ii) the eccentricity profile is largest near the inner edge of the disk and falls exponentially outward; and (iii) the results from linear theory indeed agree with what is found in simulations. Understanding the development of eccentric modes in circumbinary disks is a crucial first step for understanding the long-term (secular) exchange of eccentricity, angular momentum, and mass between the binary and the gas. Potential applications include the search for a characteristic kinematic signature in disks around candidate binaries and precession-induced modulation of accretion over long timescales.
Probing Particle Acceleration through Broadband Early Afterglow Emission of MAGIC Gamma-Ray Burst GRB 190114C
Authors: Asano Katsuaki , Murase Kohta , Toma Kenji 
Published: December 2020

Abstract
Major Atmospheric Gamma Imaging Cerenkov Telescopes (MAGIC) detected the gamma-ray afterglow of GRB 190114C, which can constrain microscopic parameters of the shock-heated plasma emitting non-thermal emission. Focusing on the early afterglow of this event, we numerically simulate the spectrum and multi-wavelength light curves with constant and wind-like circumstellar medium using a time-dependent code. Our results show that the electron acceleration timescale at the highest energies is likely shorter than 20 times the gyroperiod to reproduce the GeV gamma-ray flux and its spectral index reported by Fermi. This gives an interesting constraint on the acceleration efficiency for Weibel-mediated shocks. We also constrain the number fraction of non-thermal electrons f
e, and the temperature of the thermal electrons. The early optical emission can be explained by the thermal synchrotron emission with f
e ≲ 0.01. On the other hand, the X-ray light curves restrict efficient energy transfer from protons to the thermal electrons, and f
e ∼ 1 is required if the energy fraction of the thermal electrons is larger than ∼10%. The parameter constraints obtained in this work give important clues to probing plasma physics with relativistic shocks.
The NANOGrav 12.5 yr Data Set: Observations and Narrowband Timing of 47 Millisecond Pulsars
Authors: Alam Md F. , Arzoumanian Zaven , Baker Paul T. , Blumer Harsha , Bohler Keith E. , Brazier Adam , Brook Paul R. , Burke-Spolaor Sarah , Caballero Keeisi , Camuccio Richard S. , Chamberlain Rachel L. , Chatterjee Shami , Cordes James M. , Cornish Neil J. , Crawford Fronefield , Cromartie H. Thankful , DeCesar Megan E. , Demorest Paul B. , Dolch Timothy , Ellis Justin A. , Ferdman Robert D. , Ferrara Elizabeth C. , Fiore William , Fonseca Emmanuel , Garcia Yhamil , Garver-Daniels Nathan , Gentile Peter A. , Good Deborah C. , Gusdorff Jordan A. , Halmrast Daniel , Hazboun Jeffrey S. , Islo Kristina , Jennings Ross J. , Jessup Cody , Jones Megan L. , Kaiser Andrew R. , Kaplan David L. , Kelley Luke Zoltan , Key Joey Shapiro , Lam Michael T. , W. Lazio T. Joseph , Lorimer Duncan R. , Luo Jing , Lynch Ryan S. , Madison Dustin R. , Maraccini Kaleb , McLaughlin Maura A. , Mingarelli Chiara M. F. , Ng Cherry , Nguyen Benjamin M. X. , Nice David J. , Pennucci Timothy T. , Pol Nihan S. , Ramette Joshua , Ransom Scott M. , Ray Paul S. , Shapiro-Albert Brent J. , Siemens Xavier , Simon Joseph , Spiewak Renée , Stairs Ingrid H. , Stinebring Daniel R. , Stovall Kevin , Swiggum Joseph K. , Taylor Stephen R. , Tripepi Michael , Vallisneri Michele , Vigeland Sarah J. , Witt Caitlin A. , Zhu Weiwei ,   (The NANOGrav Collaboration)
Published: December 2020

Abstract
We present time-of-arrival (TOA) measurements and timing models of 47 millisecond pulsars observed from 2004 to 2017 at the Arecibo Observatory and the Green Bank Telescope by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav). The observing cadence was three to four weeks for most pulsars over most of this time span, with weekly observations of six sources. These data were collected for use in low-frequency gravitational wave searches and for other astrophysical purposes. We detail our observational methods and present a set of TOA measurements, based on “narrowband” analysis, in which many TOAs are calculated within narrow radio-frequency bands for data collected simultaneously across a wide bandwidth. A separate set of “wideband” TOAs will be presented in a companion paper. We detail a number of methodological changes, compared to our previous work, which yield a cleaner and more uniformly processed data set. Our timing models include several new astrometric and binary pulsar measurements, including previously unpublished values for the parallaxes of PSRs J1832−0836 and J2322+2057, the secular derivatives of the projected semimajor orbital axes of PSRs J0613−0200 and J2229+2643, and the first detection of the Shapiro delay in PSR J2145−0750. We report detectable levels of red noise in the time series for 14 pulsars. As a check on timing model reliability, we investigate the stability of astrometric parameters across data sets of different lengths. We also report flux density measurements for all pulsars observed. Searches for stochastic and continuous gravitational waves using these data will be subjects of forthcoming publications.
Design solutions for interior architecture post coronavirus
Authors: Zaher Noha 
Published: December 2020

The beginning of 2020 the Coronavirus spread threatened the whole world. The world's population forced to stay at homes - quarantine - to limit the spread of the epidemic. All our daily life practice became from home, this affect the interior spaces in shape, function and its impact on human physiological health. The research discuss the design solutions according to the instructions of world health organization from the view of interior designers and support the state’s plan innovation and development in fourth generation cities.
The priorities of the post-Coronavirus phase are to redesign environmental sustainable interior spaces for existing or new one. The research focus on the design solutions for the shared and public spaces, to get ready for the second wave of the epidemic and limiting its spread, by the usage of digital technologies that exploit our environmental resources and face the architectural design challenges in the future developments.
Fontcuberta, humorista y demiurgo: Mundos Alternativos Perfectamente Amueblados (MAPA)
Authors: Rodríguez Ferrándiz Raúl 
Published: December 2020

En esta era de posverdad, fake news y deepfake (específica alteración digital fraudulenta de documentos audiovisuales) es necesario no solo reclamar el compromiso con la verdad del informador, sino la preservación de un espacio para la ficción que no sea estigmatizado. Las ficciones artísticas son territorios delicados que han de mantener su capacidad irrestricta de revelar mediante metáforas o ironías porciones de lo real, y al tiempo imaginar mundos alternativos que desearíamos visitar (o, al contrario, de los que abominaríamos). El texto que sigue repasa cronológicamente y analiza la obra de un excepcional creador de mundos a través de imágenes, Joan Fontcuberta, con la premisa de que cada una de sus colecciones es la metódica construcción de una porción de universo. En cuarenta años de incesante creación (y reflexión sobre ella), ha parodiado gran número de discursos: científico, periodístico, histórico, religioso, artístico y de las nuevas tecnologías. La vía para conseguirlo era crear pequeños mundos y mostrarnos, con ironía, pruebas fotográficas de su existencia: fauna, flora, restos fósiles y aerolitos extraterrestres, constelaciones, accidentes geográficos y razas ignotas, astronautas y milagros, científicos y terroristas, noticiarios, periódicos, curadores de arte y artistas, incluso instituciones museísticas donde esas obras inventadas (doblemente) se expondrían. La suma de esos mundos parciales constituye un Mundo Alternativo Perfectamente Amueblado (MAPA), una cartografía casi tan completa y exigente en su coherencia interna como las que contenían la borgiana Enciclopedia de Tlön o las ficciones de Tolkien o George R. Martin.
Uma aproximação entre as políticas públicas de mobilidade urbana e os objetivos de desenvolvimento sustentável em Curitiba-PR
Authors: Locatelli Isabela Porte Vieira , Bernardinis Márcia De Andrade Pereira , Moraes Matheus Do Amaral 
Published: December 2020

Objetivo: O presente estudo tem como objetivo verificar as inter-relações entre as principais políticas públicas de mobilidade urbana em Curitiba-PR e o Objetivo de Desenvolvimento Sustentável número 11 – Cidades e Comunidades Sustentáveis.Metodologia: Com fins exploratórios e apoiado nas categorias de análise propostas pelo IBAM (2016) – que permitem a classificação das políticas em termos de mais próximo ou mais distante – o estudo se deu por meio de pesquisa documental nos sites oficiais dos órgãos públicos.Originalidade/ Relevância: Tendo em vista a crise urbana enfrentada na mobilidade e a crescente produção de políticas públicas voltadas à problemática, análises relacionadas ao tema são cada vez mais urgentes. Principais resultados: Verificou-se que há correlação entre os conteúdos das políticas analisadas e o ODS 11. Os maiores níveis de inter-relação foram com as categorias de segurança viária e sustentabilidade, enquanto os menores foram com o transporte público e a acessibilidade.Contribuições: Nesse sentido, o presente estudo se insere justamente no esforço de estabelecer categorias de análise, com base nos parâmetros estabelecidos pelas metas presentes nos ODS, como elementos norteadores em um necessário processo de mensuração e avaliação das políticas públicas e suas dinâmicas.Conclusão: Conclui-se que é preciso um contínuo processo de mensuração e avaliação das políticas públicas. Nessa óptica, os aspectos qualitativos e o panorama dos itens pesquisados apontam indícios e tendências que podem ainda orientar novos estudos.
Responses of branching reef corals Acropora digitifera and Montipora digitata to elevated temperature and pCO2
Authors: Manullang Cristiana , Millyaningrum Intan Herwindra , Iguchi Akira , Miyagi Aika , Tanaka Yasuaki , Nojiri Yukihiro , Sakai Kazuhiko 
Published: December 2020

Anthropogenic emission of CO2 into the atmosphere has been increasing exponentially, causing ocean acidification (OA) and ocean warming (OW). The “business-as-usual” scenario predicts that the atmospheric concentration of CO2 may exceed 1,000 µatm and seawater temperature may increase by up to 3 °C by the end of the 21st century. Increases in OA and OW may negatively affect the growth and survival of reef corals. In the present study, we separately examined the effects of OW and OA on the corals Acropora digitifera and Montipora digitata, which are dominant coral species occurring along the Ryukyu Archipelago, Japan, at three temperatures (28 °C, 30 °C, and 32 °C) and following four pCO2 treatments (400, 600, 800, and 1,000 µatm) in aquarium experiments. In the OW experiment, the calcification rate (p = 0.02), endosymbiont density, and maximum photosynthetic efficiency (Fv/Fm) (both p < 0.0001) decreased significantly at the highest temperature (32 °C) compared to those at the lower temperatures (28 °C and 30 °C) in both species. In the OA experiment, the calcification rate decreased significantly as pCO2 increased (p < 0.0001), whereas endosymbiont density, chlorophyll content, and Fv/Fm were not affected. The calcification rate of A. digitifera showed greater decreases from 30 °C to 32 °C than that of M. digitata. The calcification of the two species responded differently to OW and OA. These results suggest that A. digitifera is more sensitive to OW than M. digitata, whereas M. digitata is more sensitive to OA. Thus, differences in the sensitivity of the two coral species to OW and OA might be attributed to differences in the endosymbiont species and high calcification rates, respectively.
Simulation of the Dispersion of Substances Resulting from Gas Explosions
Authors: Colda Cosmin Ioan , Vlasin Nicolae Ioan , Pasculescu Vlad Mihai , Burian Constantin Sorin , Grecea Danut Nicolae 
Published: December 2020

Abstract
Directive 2014/34/EU of the European Parliament and of the Council regulates the placing on the market of equipment and protective systems intended for use in potentially explosive atmospheres. The importance of using explosion-proof equipment (certified in compliance with provisions of standards for electrical and non-electrical equipment) is crucial for avoiding catastrophic explosion-type events which may result in human victims, important material losses or may have significant consequences upon the environment. The current paper addresses a possible scenario of a pressure vessel explosion and the computational simulation and analysis of the dispersion of hazardous substances (toxic or explosive) released in the environment following the explosion-type event, in order to highlight the possible consequences. Such computational simulations may be of benefit for employers, who wish to take proactive measures in order to increase the occupational health and safety level within their activity. In this regard, results of computational simulations can be integrated by the companies in the development of emergency response plans, aiming at minimizing the hazardous effects of the releases of toxic/explosive gases upon the workers and surrounding atmosphere.
Using of evaporative cooling systems in poultry farms
Authors: Anarbaev A , Zakhidov R , Tursunov O , Kodirov D , Vakhidov U , Khaliknazarov U , Yusupov Z , Kushev A 
Published: December 2020

Abstract
This article is devoted to the development of promising low-power evaporative cooling systems in poultry farms. At the same time, the placement of elements of the system in determining the temperature, humidity and gas composition of the air in such indoor areas is determined by the parameters at which the most favorable conditions for the life of their bodies and their high productivity are created. The promising method of intensifying the process of heat and mass transfer between gaseous and liquid is considered. The article presents the structural and thermodynamic parameters of the developed evaporative cooler air. Create a layout of the plant shown efficiency and effectiveness of the cooling air. Preliminary methods of calculation thermodynamic parameters of this installation are presented for the conditions of the Republic of Uzbekistan and are more effective with comparison in widely used at present time I-d diagram.
Magnetic-soft materials based on iron for electromechanical engineering
Authors: Gapparov A U , Govor G A , Berdiyev U T , Hasanov F F , Kurbanov A M 
Published: December 2020

Abstract
This article describes the methods of using composite magnetic soft materials in the railway transport and mechanical engineering. Soil state in two modifications of Fey and Fey are formed in the iron. Also in the text, the main temperature magnetic and non-magnetic properties of materials, and magnetic properties of materials at various different temperatures are highlighted. It has been noted that other material properties change at normal temperature also. In this regard, the study of new magnetic materials based on isolated iron particles is of interest to the theory of magnetism - the study of the mechanism of magnetic exchange through thin insulating layers with the formation of single-phase ferromagnetic ordering in a multiphase crystalline system.
Damping vibrations of an underground structure using a three-mass damper
Authors: Abduvaliev A , Abdulkhayzoda A 
Published: December 2020

Abstract
The state of a rigid disk at elastic waves diffraction on it and the possibility of its oscillation suppression using a multi-mass damper was studied in the paper. The operation of a three-mass dynamic oscillation suppression was considered and its application was compared with the operation of a two-mass damper. The effectiveness of the use of multi-mass dampers was estimated by the relative amplitude of disk oscillations and by the width of the frequency zone. It was stated that to suppress disk oscillations in a state of low instability of external impact frequency, the use of single- or two-mass dampers was sufficient. To reduce the disk displacements at unstable frequency of external impact (to cover a wider frequency zone), it is necessary to use a three-mass damper; the width of the damper effective operation significantly increases (about 4-5 times) compared to the operation of a two-mass damper.
Virtual water trade in the semi-arid regions of Nigeria
Authors: Abdullahi J , Elkiran G , Aslanova F 
Published: December 2020

Abstract
With continuous growth in the world population, the demand for water increases and hence water scarcity rises. Adequate measures have to be put in place in order to make proper utilization of the available water. Virtual water trade is defined as the water volume conveyed within the imported or exported food. Hence, the aim of this study was to determine the virtual water volume required for crops production of 25 different crops in the semi-arid regions of Nigeria for the year 2013. In addition, the water footprint, imports and exports of virtual water, the production volume of virtual water, green, blue, and grey water contributions to crops production, water balance, exports income, imports costs and value of the selected crops produced were distinguished. The study was conducted using CROPWAT 8.0 software. The result revealed that in the 7 regions of the semi-arid zone, the crops selected had total volume of virtual water produced of approximately 35.9 Gm3/yr, exports volume of virtual water was 27.5 Mm3/yr, imports volume of virtual water was 8.6 Gm3/yr, water footprint was 44.5 Gm3/yr and water balance was 8.6 Gm3/y. Total value of the produced crops was $2.6 billion, export income $1.1 million and import cost $794.6 million. Gusau with higher percentage of green water used is preferable region to grow crops in the semi-arid regions of Nigeria, which can consequently lead to reduced cost of production and scarcity of water.
Soil Stabilization Using Waste Plastic Bottles Fibers: A Review Paper
Authors: Iravanian A , Haider A B 
Published: December 2020

AbstractNowadays plastic has a major role in our life use, but the increased usage of it led to a serious challenge which is plastic waste. Plastic waste is increasing day by day and which led to many bad disposal methods like burning and due to that there are many environmental and pollution problems. Therefore, there is a need to seek for safe and effective disposal methods to protect our plant and next generations’ future. One of the effective and safe solutions is using plastic waste in civil engineering construction as this solution is eco-friendly where it will provide a safe disposal as well as in engineering there is always a seek for economical materials and as plastic waste is almost for free. In addition, adding these materials may improve the properties of the construction materials. This article reviews all the published trials of using waste plastic bottles fibers as soil improvement material to examine the effectiveness of using this material as a reinforcing material in improving soil properties. As well as to provide a data base of information regarding the best dimensions and percentages. After reviewing the literature, it was found that waste plastic bottles can effectively be used as a reinforcing material and it is an eco-friendly solution. But the best benefit is it really economical as this solution has showed good improvement in soil properties this can reduce the thickness of the pavement in highways construction as well as it provided a good stabilization method rather than the other expensive methods. This material also can solve the problem of time as the other stabilization take much time which delay the construction process. Also, it was found that the addition of (0-5) % with higher aspect ratios give the optimum results.