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2022 ◽  
Vol 163 (2) ◽  
pp. 49
Author(s):  
N. Luber ◽  
Sarah Pearson ◽  
Mary E. Putman ◽  
Gurtina Besla ◽  
Sabrina Stierwalt ◽  
...  

Abstract We present resolved H i synthesis maps from the Very Large Array of three interacting dwarf systems: the NGC 3664 dwarf pair, the NGC 3264 dwarf pair, and the UGC 4638 dwarf triplet. All three dwarf systems are captured at various stages of interaction and span a range of environments. We detect clear hallmarks of tidal interactions through the presence of H i bridges and diffuse H i extensions that surround the dwarfs. We overlay the H i data on Pan-STARRS r-band images and find further evidence of tidal interactions through coincident distorted H i and tidal stellar features in NGC 3264 and UGC 4638, and an unwound spiral arm pointing toward its smaller companion in NGC 3264. In UGC 4638, both the gas and diffuse stars are extended to similar radii east of the primary, which could indicate that the smaller dwarf in the system has already completed one pass through the primary. We additionally find that our three systems, and those from the Local Volume TiNy Titans survey, are not H i deficient and thus the interaction has not resulted in a loss of gas from the systems. A comparison with noninteracting dwarf galaxies shows that the interactions have a significant impact on the kinematics of the systems. Our new resolved H i kinematics, combined with detailed stellar and H i morphologies, provide crucial constraints for future dynamical modeling of hierarchical mergers and the baryon cycle at the low-mass scale.


2021 ◽  
Vol 6 (16) ◽  
pp. 63-70
Author(s):  
Anna Hedo ◽  
Olha Kryhina

This article is an attempt to review religious and cultural features and to find published images on the pages of parish registers of different creeds. To determine and study the relevant and cultural features of the information recording in the parish registers, we considered appropriate to consolidate the comparative and historical-cultural method. The interest of scholars and novelty are proved due to the extremely large information potential of the church reports of civil status, considering their large array in the state archives and satisfactory physical status, suitable for appendage.The study of ecclesiastical acts of civil status makes it possible to study the religious and cultural peculiarities via the records characteristic for representatives of different religions. We should separately mention the peculiarities of the entries in parish registers of the Orthodox population regarding the veneration of holy figures according to the church calendar, which impacted the naming of newborns. Jewish records are characterized by the rite of circumcision of newborn boys and records as for a marriage contract (“ksubba / ktubba”).German-language parish registers attract attention to the double names given to newborn babies, the obligation to declare an forthcoming marriage, and the presence of family information in records of the deceased.


2021 ◽  
Author(s):  
Laura P. Schaposnik ◽  
Sheryl Hsu ◽  
Fidel I. Schaposnik Massolo

Abstract This paper presents a novel explore-and-fuse approach to solving a large array of problems that cannot be solved by traditional divide-and-conquer. This approach is inspired by Physarum, a unicellular slime mold capable of solving the traveling salesman and Steiner tree problems. Besides exhibiting individual intelligence, Physarum can also share information with other Physarum organisms through fusion. Inspired by the characteristics of Physarum, we spawn many Physarum organisms to explore the problem space in parallel, each gathering information and forming partial solutions pertaining to a local region of the problem space. When the organisms meet, they fuse and share information, eventually forming one organism which has a global view of the problem and can apply its intelligence to find an overall solution to the problem. We demonstrate this novel approach on the NP-hard Steiner tree problem, developing the Physarum Steiner Algorithm. This algorithm is of particular interest due to its ability to leverage parallel processing, avoid obstacles, and operate on various shapes and topological surfaces including the rectilinear grid.


2021 ◽  
Vol 163 (1) ◽  
pp. 15
Author(s):  
Y. Cendes ◽  
P. K. G. Williams ◽  
E. Berger

Abstract We present the first systematic search for GHz frequency radio emission from directly imaged exoplanets using Very Large Array observations of sufficient angular resolution to separate the planets from their host stars. We obtained results for five systems and eight exoplanets located at ≲50 pc through new observations (Ross 458, GU Psc, and 51 Eri) and archival data (GJ 504 and HR 8799). We do not detect radio emission from any of the exoplanets, with 3σ luminosity upper limits of (0.9–23) × 1021 erg s−1. These limits are comparable to the level of radio emission detected in several ultracool dwarfs, including T dwarfs, whose masses are only a factor of two times higher than those of the directly imaged exoplanets. Despite the lack of detections in this pilot study, we highlight the need for continued GHz frequency radio observations of nearby exoplanets at μJy-level sensitivity.


Galaxies ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 112
Author(s):  
Valentina Vacca ◽  
Federica Govoni ◽  
Richard A. Perley ◽  
Matteo Murgia ◽  
Ettore Carretti ◽  
...  

The galaxy cluster Abell 523 hosts a radio halo characterized by the presence of two filaments transversely located with respect to the cluster merger axis. In this paper, we present a spectral index image of these filaments between 1.410 and 1.782 GHz obtained with Jansky Very Large Array observations. We find a steepening of the spectral index of the filaments at frequencies ≳1.4 GHz and an indication that bright patches are characterized by flat spectral indices. Our results are consistent with a scenario of highly-efficient turbulence induced by merger phenomena.


2021 ◽  
Vol 66 (2) ◽  
pp. 247-253
Author(s):  
Aurel Muraru

"Facial expressions can be regarded as an accurate reflection of the inner emotions people manifest towards the surrounding reality, filtered through their own emotional „strainer”. The source of these feelings lies not only in external influences, but also in a man's own thoughts, experiences, level of education and culture, as well as the degree of development of their own volitional and emotional capacities, in which muscle movements are merely just a simple mechanical means of rendering. The entire array of facial expressions acts as a unitary system which does nothing but complete the movements of the conductor's hands, filling them with meaning. We can say that this type of communication represents a way of combining the most delicate, vibrant, profound, and subtle feelings. It would be impossible to imagine that the movement of the arms, unsupported by the expression of the eyes and face or by the position of the body, were able to express a large array of emotions (joy, pain, sadness, rage, fear, surprise, or confidence) accurately and unequivocally. Keywords: facial expressions, mimicry, nonverbal communication, conductor, performance. "


2021 ◽  
Vol 923 (1) ◽  
pp. 3
Author(s):  
Amruta D. Jaodand ◽  
Adam T. Deller ◽  
Nina Gusinskaia ◽  
Jason W. T. Hessels ◽  
James C. A. Miller-Jones ◽  
...  

Abstract 3FGL J1544.6−1125 is a candidate transitional millisecond pulsar (tMSP). Similar to the well-established tMSPs—PSR J1023+0038, IGR J18245−2452, and XSS J12270−4859—3FGL J1544.6−1125 shows γ-ray emission and discrete X-ray “low” and “high” modes during its low-luminosity accretion-disk state. Coordinated radio/X-ray observations of PSR J1023+0038 in its current low-luminosity accretion-disk state showed rapidly variable radio continuum emission—possibly originating from a compact, self-absorbed jet, the “propellering” of accretion material, and/or pulsar moding. 3FGL J1544.6−1125 is currently the only other (candidate) tMSP system in this state, and can be studied to see whether tMSPs are typically radio-loud compared to other neutron star binaries. In this work, we present a quasi-simultaneous Very Large Array and Swift radio/X-ray campaign on 3FGL J1544.6−1125. We detect 10 GHz radio emission varying in flux density from 47.7 ± 6.0 μJy down to ≲15 μJy (3σ upper limit) at four epochs spanning three weeks. At the brightest epoch, the radio luminosity is L 5 GHz = (2.17 ± 0.17) × 1027 erg s−1 for a quasi-simultaneous X-ray luminosity L 2–10 keV = (4.32 ± 0.23) × 1033 erg s−1 (for an assumed distance of 3.8 kpc). These luminosities are close to those of PSR J1023+0038, and the results strengthen the case that 3FGL J1544.6−1125 is a tMSP showing similar phenomenology to PSR J1023+0038.


2021 ◽  
Vol 923 (2) ◽  
pp. 263
Author(s):  
A. P. M. Towner ◽  
C. L. Brogan ◽  
T. R. Hunter ◽  
C. J. Cyganowski

Abstract We have observed a sample of nine Extended Green Objects (EGOs) at 1.3 and 5 cm with the Very Large Array (VLA) with subarcsecond resolution and ∼7–14 μJy beam−1-sensitivities in order to characterize centimeter continuum emission as it first appears in these massive protoclusters. We find an EGO-associated continu um emission—within 1″ of the extended 4.5 μm emission—in every field, which is typically faint (order 101–102 μJy) and compact (unresolved at 0″.3–0″.5). The derived spectral indices of our 36 total detections are consistent with a wide array of physical processes, including both non-thermal (19% of detections) and thermal free–free processes (e.g., ionized jets and compact H ii regions, 78% of sample) and warm dust (1 source). We also find an EGO-associated 6.7 GHz CH3OH and 22 GHz H2O maser emission in 100% of the sample and a NH3 (3,3) masers in ∼45%; we do not detect any NH3 (6,6) masers at ∼5.6 mJy beam−1 sensitivity. We find statistically-significant correlations between L radio and L bol at two physical scales and three frequencies, consistent with thermal emission from ionized jets, but no correlation between L H 2 O and L radio for our sample. From these data, we conclude that EGOs likely host multiple different centimeter continuum-producing processes simultaneously. Additionally, at our ∼1000 au resolution, we find that all EGOs except G18.89−0.47 contain 1 ∼ 2 massive sources based on the presence of CH3OH maser groups, which is consistent with our previous work suggesting that these are typical massive protoclusters, in which only one to a few of the young stellar objects are massive.


2021 ◽  
Vol 923 (2) ◽  
pp. L24
Author(s):  
Michael C. Stroh ◽  
Giacomo Terreran ◽  
Deanne L. Coppejans ◽  
Joe S. Bright ◽  
Raffaella Margutti ◽  
...  

Abstract We present a population of 19 radio-luminous supernovae (SNe) with emission reaching L ν ∼ 1026–1029 erg s−1 Hz−1 in the first epoch of the Very Large Array Sky Survey (VLASS) at 2–4 GHz. Our sample includes one long gamma-ray burst, SN 2017iuk/GRB 171205A, and 18 core-collapse SNe detected at ≈1–60 yr after explosion. No thermonuclear explosion shows evidence for bright radio emission, and hydrogen-poor progenitors dominate the subsample of core-collapse events with spectroscopic classification at the time of explosion (79%). We interpret these findings in the context of the expected radio emission from the forward shock interaction with the circumstellar medium (CSM). We conclude that these observations require a departure from the single wind–like density profile (i.e., ρ CSM ∝ r −2) that is expected around massive stars and/or from a spherical Newtonian shock. Viable alternatives include the shock interaction with a detached, dense shell of CSM formed by a large effective progenitor mass-loss rate, M ̇ ∼ 10 − 4 – 10 − 1 M ⊙ yr−1 (for an assumed wind velocity of 1000 km s−1); emission from an off-axis relativistic jet entering our line of sight; or the emergence of emission from a newly born pulsar-wind nebula. The relativistic SN 2012ap that is detected 5.7 and 8.5 yr after explosion with L ν ∼ 1028 erg s−1 Hz−1 might constitute the first detections of an off-axis jet+cocoon system in a massive star. However, none of the VLASS SNe with archival data points are consistent with our model off-axis jet light curves. Future multiwavelength observations will distinguish among these scenarios. Our VLASS source catalogs, which were used to perform the VLASS cross-matching, are publicly available at https://doi.org/10.5281/zenodo.4895112.


2021 ◽  
Author(s):  
Annie Lauzier ◽  
Marie-France Bossanyi ◽  
Raphaëlle Larcher ◽  
Sonya Nassari ◽  
Rupali Ugrankar ◽  
...  

Macroautophagy, the degradation and recycling of cytosolic components in the lysosome, is an important cellular mechanism. It is a membrane-mediated process that is linked to vesicular trafficking events. The sorting nexin (SNX) protein family controls the sorting of a large array of cargoes, and various SNXs impact autophagy. To improve our understanding of their functions in vivo, we screened all Drosophila SNXs using inducible RNA interference in the fat body. Significantly, depletion of snazarus (snz) led to decreased autophagic flux. Interestingly, we observed altered distribution of Vamp7-positive vesicles with snz depletion, and snz's roles were conserved in human cells. SNX25, the closest human ortholog to snz, regulates both VAMP8 endocytosis and lipid metabolism. Through knockout-rescue experiments, we demonstrate that these activities are dependent on specific SNX25 domains and that the autophagic defects upon SNX25 loss can be rescued by ethanolamine addition. We also demonstrate the presence of differentially spliced forms of SNX14 and SNX25 in cancer cells. This work identifies a conserved role for snz/SNX25 as regulators of autophagic flux and reveals differential isoform expression between paralogs.


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