Miracle-dz/UniFAR-FTUs huggingface dataset:
Timescales of major mergers from simulations of isolated binary galaxy collisions

A six-dimensional parameter space based on high-resolution numerical simulations of isolated binary galaxy collisions has been constructed to investigate the dynamical friction timescales, τmer, for major mergers. Our experiments follow the gravitational encounters between ∼600 pairs of similarly massive late- and early-type galaxies with orbital parameters that meet the predictions of the Λ-cold dark matter (ΛCDM) cosmology. We analyse the performance of different schemes for tracking the secular evolution of mergers, finding that the product of the intergalactic distance and velocity is best suited to identify the time of coalescence. In contrast, a widely used merger-time estimator such as the exhaustion of the orbital spin is shown to systematically underpredict τmer, resulting in relative errors that can reach 60% for nearly radial encounters. We find that the internal spins of the progenitors can lead to total variations in the merger times larger than 30% in highly circular encounters, whereas only the spin of the principal halo is capable of modulating the strength of the interaction prevailing throughout a merger. The comparison of our simulated merger times with predictions from different variants of a well-known fitting formula has revealed an only partially satisfactory agreement, which has led us to recalculate the values of the coefficients of these expressions to obtain relations that fit major mergers perfectly. The observed biases between data and predictions, which do not only apply to the present work, are inconsistent with expectations from differences in the degree of idealisation of the collisions, their metric, spin-related biases, or the simulation set-up. This indicates a certain lack of accuracy of the dynamical friction modelling, arising perhaps from a still incomplete identification of the parameters governing orbital decay.
AEGIS: The Environment of X-Ray Sources at z ≈ 1

We explore the environment of z ≈ 1 AGNs using a sample of 53 spectroscopically identified X-ray sources in the All-Wavelength Extended Groth Strip International Survey. We quantify the local density in the vicinity of an X-ray source by measuring the projected surface density of spectroscopically identified optical galaxies within a radius defined by the third-nearest neighbor. Our main result is that X-ray-selected AGNs at z ≈ 1 avoid underdense regions at a 99.89% confidence level. Moreover, although we find that the overall population shares the same (rich) environment with optical galaxies of the similar U - B and MB, there is also tentative evidence (96%) that AGNs with blue colors (U - B ≲ 1) reside in denser environments compared to optical galaxies. We argue that the results above are a consequence of the whereabouts of massive galaxies capable of hosting supermassive black holes at their centers, with available cold-gas reservoirs, the fuel for AGN activity. At z ≈ 1 an increasing fraction of such systems is found in dense regions.
Candidate Tidal Dwarf Galaxies Associated with Stephan’s Quintet

We present kinematic and photometric evidence for the presence of seven candidate tidal dwarf galaxies in Stephan's Quintet. The central regions of the two most probable parent galaxies, NGC 7319 and NGC 7318B, contain little or no gas whereas the intragroup medium and, in particular, the optical tails that seem to be associated with NGC 7318B are rich in cold and ionized gas. Two tidal dwarf candidates may be located at the edge of a tidal tail, another located within a tail, and for the four others there is no obvious stellar/gaseous bridge between them and the parent galaxy. Two of the candidates are associated with H I clouds, one of which is, in addition, associated with a CO cloud. All seven regions have low continuum fluxes and high Hα luminosity densities [F(Hα) = (1–60) × 10-14 ergs s-1 cm-2]. Their magnitudes (MB = -16.1 to -12.6), sizes (∼3.5 h kpc), colors (typically B-R = 0.7), and gas velocity gradients (∼8–26 h75 km s-1 kpc-1) are typical for tidal dwarf galaxies. In addition, the ratios between their star formation rates determined from Hα and from the B-band luminosity are typical of other tidal dwarf galaxies. The masses of the tidal dwarf galaxies in Stephan's Quintet range from ∼2 × 108 to 1010 M⊙, and the median value for their inferred mass-to-light ratios is 7 (M/L)⊙. At least two of the systems may survive possible "fallbacks" or disruption by the parent galaxies and may already be, or turn into, self-gravitating dwarf galaxies, new members of the group.
Changes in flooding in the alpine catchments of the Tarim River Basin, Central Asia

Floods are one of the most affective climate‐related disasters, and climate change has altered their intensity and frequency worldwide. This study examined long‐term changes in flood characteristics (including magnitude, frequency, and timing) in 30 alpine headwaters of the large endorheic Tarim River Basin, Central Asia. The contributions of climatic factors to flood (magnitude and timing) changes were investigated using numerical experiments in combination with the random forest approach. The following results were obtained: (1) Annual maximum flood peaks increased at most stations (89% stations) during 1961–2015 with increased flood frequency. Earlier flood peaks were observed in spring with a rate of 1.38 day per decade; for other seasons, changes in the occurrence time of flood peaks showed strong spatial variability. (2) Precipitation was the dominant factor for the increased flood magnitude in most catchments of the southern slope of the Tianshan Mountains, and temperature played a greater role in the northern Kunlun Mountains. (3) For flood timing changes, melt level height and precipitation were the most influential factors in the alpine catchments in the Tarim River Basin. The results provide information on the spatiotemporal variations of floods and their driving factors in this alpine basin under climate change.
A stochastic model for acoustic attenuation

Propagation of waves in gases or liquids has been observed for a long time in homogeneous or non-homogeneous media. In acoustics, attenuation is a significant problem which is studied mainly through the ‘equations of change’ of fluid mechanics. These equations are based only on the macroscopic characteristics of the medium. Microscopic variations, related to other phenomena like Brownian motion or critical opalescence, are not taken into account. This paper provides a random one-ray model. This model explains the proportionality between the standard attenuation and the product between length and frequency squared in a logarithmic scale. The wave is shown to be necessarily associated with noise, even if this noise cannot be observed by devices. Furthermore, the ‘coefficient of variation’ defined in turbulent environments can be explained as a random version of the usual coefficient of attenuation.
Toward Decolonizing Our Scholarship and Discourses: Lessons From the Special Issue on Decoloniality for EAQ

Members of the Educational Administration Quarterly (EAQ) internal editorial team took a critical look at the publication record of our journal with respect to epistemological plurality over the past 10 years. Our goal was to identify international publication trends and highlight how pluralized the research frames are within EAQ. Data overwhelmingly show that EAQ is a largely U.S.-centric publication, even when the topics explored touch on critical or epistemological concerns. The implications of these findings are discussed.
Effect of management and probiotic supplementation on growth performance of Muscovy duck

Background: Farming of Muscovy ducks ( Cairina moschata ) is an important part of the poultry industry in developed countries. However, the lack of research and improvement programs has led to poor productive outcomes in developing regions where this duck breed is important to procure adequate food security. Objective: To evaluate the effect of improved management conditions and the use of commercial probiotics on the growth performance of Muscovy ducks in a semi-intensive system farm in Colombia. Methods: We recorded the weight gain and feed conversion ratio (FCR) of ducks under three treatments: Backyard management, improved management, and improved management plus probiotic supplementation. Results: The backyard farming system led to poor weight gains (male=2,797 g; female=1,605 g) and less efficient FCR (4.06). Improvement of management conditions led to a better (p<0.05) FCR (3.1) and a greater (p<0.05) weight gain (male=2,888 g; female=1,637 g). The FCR under improved management is comparable to those reported in developed duck farming industries, but the final weight was notably lower than those obtained with selected lines. The use of commercial probiotics led to significant (p<0.05) improvement in weight gain (male=2,930 g; female=1,692 g); however, it also increased the FCR (3.5; p<0.05). Conclusions: The improvement of management conditions enhance the productivity of Muscovy ducks, but further genetic selection processes or use of selected lines is required in developing countries such as Colombia. Further studies are required to assess if probiotic supplementation can lead to improvement in Muscovy ducks farming due to the contrasting effect over the weight gain and FCR.
Telemedicine Adoption during Pandemic Covid19 in Indonesia

This research will investigated adoption of telemedicine in Indonesia during pandemic COVID19 by modifying Unified Theory of Acceptance and Use of Technology (UTAUT). Variables used in this research are performance expectancy, effort expectancy, social influence, attitude an facilitating conditions as moderating variables that use to analyze use behavior of telemedicine in Indonesia. The survey conducted on 317 telemedicine user in Indonesia and analysis using moderated regression analysis. Based on the results of data analysis, as many as 4 hypotheses were rejected while only three were accepted. The accepted hypotheses state that performance expectation and attitude, as well as the moderating effect of facilitating conditions, have an impact on the influence of social influence on telemedicine usage behavior. Meanwhile, the rejected hypotheses are those which state that there is a direct influence of effort expectancy, social influence, attitudes towards telemedicine usage behavior and moderating effects of facilitating conditions on the effect of performance expectancy and attitudes towards telemedicine usage behavior. As implications, telemedicine must be designed to offer greater benefits than conventional medical services, such as time savings and cost savings. Furthermore, despite the lack of a direct physical examination in telemedicine, the results of the diagnosis are expected to be accurate, resulting in the patient being more productive and healthy as a result of adopting telemedicine
Comparison of the pull-out bond strength of endodontically treated anterior teeth with monolithic zirconia endocrown and post-and-core crown restorations.

PURPOSE The purpose of this study was to assess the pull-out bond strength (PBS) of endodontically treated anterior teeth that had been restored with monolithic zirconia endocrowns using different extension depths (EDs) and post-and-core crowns after chewing simulation. METHODS Thirty-six maxillary central teeth were used (n = 12). Group I: Glass fiber post-and-core crown, Group II: Endocrown with 3-mm EDs, Group III: Endocrown with 5-mm EDs. Restorations were fabricated from monolithic zirconia blocks using a CAM (computer-aided manufacturing) device. For cementation, conventional resin luting agent (Multilink N) was used. All samples were aged with a chewing simulator and PBS tests were conducted at a speed of 1 mm/min using an electromechanical servo universal testing machine. The values were recorded in MPa by dividing the failure load by the bonding area. One-way ANOVA and the post-hoc Tukey test were used for statistical analysis (P = 0.05). RESULTS Group III demonstrated significantly greater PBS values than Groups I and II (P = 0.001). No significant difference was found between Groups I and II (P = 0.072). CONCLUSION Increasing the ED of an endocrown influences the PBS of endodontically treated anterior teeth restored with monolithic zirconia endocrowns.
Chandra Temperature Profiles for a Sample of Nearby Relaxed Galaxy Clusters

We present Chandra gas temperature profiles at large radii for a sample of 13 nearby, relaxed galaxy clusters and groups, which includes A133, A262, A383, A478, A907, A1413, A1795, A1991, A2029, A2390, MKW 4, RX J1159+5531, and USGC S152. The sample covers a range of average temperatures from 1 to 10 keV. The clusters are selected from the archive or observed by us to have sufficient exposures and off-center area coverage to enable accurate background subtraction and reach the temperature accuracy of better than 20%-30% at least to r = (0.4-0.5)r180 and for the three best clusters to (0.6-0.7)r180. For all clusters, we find cool gas in the cores, outside of which the temperature reaches a peak at r ~ 0.15r180 and then declines to ~0.5 of its peak value at r ≃ 0.5r180. When the profiles are scaled by the cluster average temperature (excluding cool cores) and the estimated virial radius, they show large scatter at small radii but remarkable similarity at r > (0.1-0.2)r180 for all but one cluster (A2390). Our results are in good agreement with previous measurements from ASCA by Markevitch et al. and from BeppoSAX by De Grandi & Molendi. Four clusters have recent XMM-Newton temperature profiles, two of which agree with our results, and we discuss reasons for disagreement for the other two. The overall shape of the temperature profiles at large radii is reproduced in recent cosmological simulations.
Contribution of HI-bearing ultra-diffuse galaxies to the cosmic number density of galaxies

We estimate the cosmic number density of the recently identified class of HI-bearing ultra-diffuse sources (HUDs) based on the completeness limits of the ALFALFA survey. These objects have HI masses approximately in the range 8.5 < logMHI∕M⊙ < 9.5, average r-band surface brightnesses fainter than 24 mag arcsec−2, half-light radii greater than 1.5 kpc, and are separated from neighbours by at least 350 kpc. In this work we demonstrate that they contribute at most ~6% of the population of HI-bearing dwarfs detected by ALFALFA (with similar HI masses), have a total cosmic number density of (1.5 ± 0.6) × 10−3 Mpc−3, and an HI mass density of (6.0 ± 0.8) × 105 M⊙ Mpc−3. We estimate that this is similar to the total cosmic number density of ultra-diffuse galaxies (UDGs) in groups and clusters, and conclude that the relation between the number of UDGs hosted in a halo and the halo mass must have a break below M200 ~ 1012 M⊙ in order to account for the abundance of HUDs in the field. The distribution of the velocity widths of HUDs rises steeply towards low values, indicating a preference for slow rotation rates compared to the global HI-rich dwarf population. These objects were already included in previous measurements of the HI mass function, but have been absent from measurements of the galaxy stellar mass function owing to their low surface brightness. However, we estimate that due to their low number density the inclusion of HUDs would constitute a correction of less than 1%. Comparison with the Santa Cruz semi-analytic model shows that it produces HI-rich central UDGs that have similar colours to HUDs, but that these UDGs are currently produced in a much greater number. While previous results from this sample have favoured formation scenarios where HUDs form in high spin-parameter halos, comparisons with recent results which invoke that formation mechanism reveal that this model produces an order of magnitude more field UDGs than we observe in the HUD population, and these have an occurrence rate (relative to other dwarfs) that is approximately double what we observe. In addition, the colours of HUDs are bluer than predicted, although we suspect this is due to a systematic problem in reproducing the star formation histories of low-mass galaxies rather than being specific to the ultra-diffuse nature of these sources.
Fluctuating feedback-regulated escape fraction of ionizing radiation in low-mass, high-redshift galaxies

Low mass galaxies are thought to provide the bulk of the ionizing radiation necessary to reionize the Universe. The amount of photons escaping the galaxies is poorly constrained theoretically, and difficult to measure observationally. Yet it is an essential parameter of reionization models. We study in detail how ionizing radiation can leak from high redshift galaxies. For this purpose, we use a series of high resolution radiation hydrodynamics simulations, zooming on three dwarf galaxies in a cosmological context. We find that the energy and momentum input from the supernova explosions has a pivotal role in regulating the escape fraction, by disrupting dense star forming clumps, and clearing sight lines in the halo. In the absence of supernovae, photons are absorbed very locally, within the birth clouds of massive stars. We follow the time evolution of the escape fraction, and find that it can vary by more than six orders of magnitude. This explains the large scatter in the value of the escape fraction found by previous studies. This fast variability also impacts the observability of the sources of reionization: a survey even as deep as $M_{\rm UV} = -14$ would miss about half of the underlying population of Lyman-continuum emitters.
Occurrence, Antimicrobial Susceptibility and Phylogroups of Escherichia coli O157:H7 Isolated from Food Outlets in Some Touristic Cities in Egypt

Foodborne illnesses are frequently caused by Escherichia coli ( E. coli ). E. coli O157 is regarded as a potentially harmful cause of gastrointestinal disorders associated with consumption of foods with animal origin. Therefore, this study was conducted to determine the presence of E. coli O157:H7 in food outlets in some touristic cities in Egypt. For this purpose, 648 samples including raw chicken meat, cooked chicken meat, raw beef meat, cooked beef meat, food handlers and equipment swabs were collected from 54 food outlets in some touristic cities in Egypt. E. coli O157 was 1.1% (7/648) and 1.2% (5/432) in all examined samples and food samples respectively. Cooked chicken samples were the most contaminated with E. coli O157:H7 with an overall prevalence of 1.9% (2/108). The highest prevalence of E. coli O157:H7 (8.3%) isolates was recovered from raw chicken and cooked beef meat in Hurghada Governorate followed by Luxor Governorate (6.3%). There is no E. coli O157:H7 isolates were identified in Sharm El Sheikh and Aswan governorates. All E. coli O157:H7 isolates (100%) showed resistance to ampicillin (AMP), cefixime, ciprofloxacin and cotrimoxazole. Multidrug resistance (MDR) was observed among all E. coli O157:H7 isolates. All E. coli O157:H7 isolates harbor the eae gene with complete absence of stx1 gene. The most prevalent phylogroup among the E. coli O157:H7 strains was B2 identified in raw and cooked beef and cooked chicken, collected from Luxor, Hurghada, and Alexandria governorates, respectively. Whereas, D phylogenetic group E. coli O157:H7 was only found in raw chicken sample collected from Hurghada Governorate. In conclusion, the detection of pathogenic MDR E. coli O157:H7 in food samples, food handlers and food equipment in some touristic cities in Egypt poses a serious risk to public health. Therefore, it is recommended to focus on identifying practices which increase the risk of food contamination, and on implementing measures to improve the sanitary conditions in the food outlets in touristic cities.
Low-temperature, in situ tunable, uniaxial stress measurements in semiconductors using a piezoelectric actuator

We demonstrate the use of a piezoelectric actuator to apply, at low temperatures, uniaxial stress in the plane of a two-dimensional electron system confined to a modulation-doped AlAs quantum well. Via the application of stress, which can be tuned in situ and continuously, we control the energies and occupations of the conduction-band minima and the electronic properties of the electron system. We also report measurements of the longitudinal and transverse strain versus bias for the actuator at 300, 77, and 4.2 K. A pronounced hysteresis is observed at 300 and 77 K, while at 4.2 K, strain is nearly linear and shows very little hysteresis with the applied bias.
MUM: flexible precise Monte Carlo algorithm for muon propagation through thick layers of matter

We present a new Monte Carlo muon propagation algorithm MUM (MUons+Medium) which possesses some advantages over analogous algorithms presently in use. The most important features of algorithm are described. Results on the test for accuracy of treatment the muon energy loss with MUM are presented and analyzed. It is evaluated to be of 0.002 or better, depending upon simulation parameters. Contributions of different simplifications which are applied at Monte Carlo muon transportation to the resulting error are considered and ranked. It is shown that when simulating muon propagation through medium it is quite enough to account only for fluctuations in radiative energy loss with fraction of energy lost being as large as 0.05 -- 0.1. Selected results obtained with MUM are given and compared with ones from other algorithms.
A DSP-Purposed REconfigurable Acceleration Machine (DREAM) for High Energy Efficiency MIMO Signal Processing

The wireless baseband processing algorithms are still developing and show a great diversity. The development of ASIC implementations cannot quickly adapt to the evolution of algorithms and standards. Meanwhile, the general-purpose processors cannot meet the real-time requirements in some scenarios. This paper proposes a DSP-purposed REconfigurable Acceleration Machine (DREAM) core for wireless baseband digital signal processing, which has a good trade-off between flexibility and performance. First, we abstract a set of shared operators with a moderate granularity from a variety of wireless MIMO signal processing algorithms. Then, we propose a two-step configuration process to reduce the size of the required reconfiguration bits. Besides, we design a conflict-free address generator to transfer data between the on-chip scratchpad memory and reconfiguration processing elements with high efficiency and high throughput. Finally, the prototype DREAM core has been implemented in TSMC CMOS 28 nm, and its area and power consumption have been analyzed. The chip has great flexibility in supporting a variety of wireless MIMO processing algorithms and a wide range of MIMO scales. The proposed DREAM core can achieve the normalized area efficiency and the normalized energy efficiency of <inline-formula> <tex-math notation="LaTeX">$0.67~Gbps/MGE$ </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">$15.05~Gbps/W$ </tex-math></inline-formula>, which are <inline-formula> <tex-math notation="LaTeX">$1.56\times $ </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">$4.18\times $ </tex-math></inline-formula> those of state-of-the-art reconfigurable implementations when running the WeJi-based MIMO detection algorithm.