bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimised disjoint virtual backbone algorithms for wireless sensor networks
Authors: Obenofunde Simon T. , Togni Olivier , Abdou Wahabou 
Published: September 2021

AbstractThe way nodes are arranged in a wireless network can significantly influence performance, especially information flow. The construction of disjoint virtual backbone networks (DVBNs) is one of the ways this can be accomplished. In this study, the authors first present a proposal that constructs multiple DVBNs using nodes' locations, in two phases. In the second phase of the proposal, dominator selection is initiated by the sink and then continued by each selected dominator. This occurs in rounds, with each round producing a distinct virtual backbone. The simulations show that multiple DVBNs can be produced with a good approximation ratio. Further, two optimisations are presented, one for a scanty network and the other for data dissemination. These are accomplished by changing the way in which the dominators are selected in the second phase of the algorithm. These optimisations are evaluated and a marked improvement is observed in node connectedness to the backbone and in hop count while keeping approximation ratios almost constant.
Fossil group origins
Authors: Zarattini S. , Biviano A. , Aguerri J. A. L. , Girardi M. , D’Onghia E. 
Published: September 2021

Aims. We aim to study how the orbits of galaxies in clusters depend on the prominence of the corresponding central galaxies.
Methods. We divided our data set of ∼100 clusters and groups into four samples based on their magnitude gap between the two brightest members, Δm12. We then stacked all the systems in each sample in order to create four stacked clusters and derive the mass and velocity anisotropy profiles for the four groups of clusters using the MAMPOSSt procedure. Once the mass profile is known, we also obtain the (non-parametric) velocity anisotropy profile via the inversion of the Jeans equation.
Results. In systems with the largest Δm12, galaxy orbits are generally radial, except near the centre, where orbits are isotropic (or tangential when also the central galaxies are considered in the analysis). In the other three samples with smaller Δm12, galaxy orbits are isotropic or only mildly radial.
Conclusions. Our study supports the results of numerical simulations that identify radial orbits of galaxies as the cause of an increasing Δm12 in groups.
SOLIS
Authors: Codella C. , Bianchi E. , Podio L. , Mercimek S. , Ceccarelli C. , López-Sepulcre A. , Bachiller R. , Caselli P. , Sakai N. , Neri R. , Fontani F. , Favre C. , Balucani N. , Lefloch B. , Viti S. , Yamamoto S. 
Published: September 2021

Context. Recent results in astrochemistry have revealed that some molecules, such as interstellar complex organic species and deuterated species, can serve as valuable tools in the investigation of star-forming regions. Sulphuretted species can also be used to follow the chemical evolution of the early stages of a Sun-like star formation process.
Aims. The goal is to obtain a census of S-bearing species using interferometric images towards SVS13-A, a Class I object associated with a hot corino that is rich in interstellar complex organic molecules.
Methods. To this end, we used the NGC 1333 SVS13-A data at 3 mm and 1.4 mm obtained with the IRAM-NOEMA interferometer in the framework of the SOLIS (Seeds of Life in Space) Large Program. The line emission of S-bearing species was imaged and analyzed using local thermodynamic equilibrium (LTE) and large velocity gradient (LVG) approaches.
Results. We imaged the spatial distribution on ≤300 au scale of the line emission of 32SO, 34SO, C32S, C34S, C33S, OCS, H2C32S, H2C34S, and NS. The low excitation (9 K) 32SO line traces: (i) the low-velocity SVS13-A outflow and (ii) the fast (up to 100 km s−1 away from the systemic velocity) collimated jet driven by the nearby SVS13-B Class 0 object. Conversely, the rest of the lines are confined in the inner SVS13-A region, where complex organics were previously imaged. More specifically, the non-LTE LVG analysis of SO, SO2, and H2CS indicates a hot corino origin (size in the 60–120 au range). Temperatures between 50 K and 300 K, as well as volume densities larger than 105 cm−3 have been derived. The abundances of the sulphuretted are in the following ranges: 0.3–6 × 10−6 (CS), 7 × 10−9–1 × 10−7 (SO), 1–10 × 10−7 (SO2), a few 10−10 (H2CS and OCS), and 10−10–10−9 (NS). The N(NS)/N(NS+) ratio is larger than 10, supporting the assessment that the NS+ ion is mainly formed in the extended envelope.
Conclusions. The [H2CS]/[H2CO] ratio, once measured at high-spatial resolutions, increases with time (from Class 0 to Class II objects) by more than one order of magnitude (from ≤10−2 to a few 10−1). This suggests that [S]/[O] changes along the process of Sun-like star formation. Finally, the estimate of the [S]/[H] budget in SVS13-A is 2–17% of the Solar System value (1.8 × 10−5), which is consistent with what was previously measured towards Class 0 objects (1–8%). This finding supports the notion that the enrichment of the sulphuretted species with respect to dark clouds remains constant from the Class 0 to the Class I stages of low-mass star formation. The present findings stress the importance of investigating the chemistry of star-forming regions using large observational surveys as well as sampling regions on the scale of the Solar System.
Reconstructing solar irradiance from historical Ca II K observations
Authors: Chatzistergos Theodosios , Krivova Natalie A. , Ermolli Ilaria , Yeo Kok Leng , Mandal Sudip , Solanki Sami K. , Kopp Greg , Malherbe Jean-Marie 
Published: September 2021

Context.Knowledge of solar irradiance variability is critical to Earth’s climate models and understanding the solar influence on Earth’s climate. Direct solar irradiance measurements have only been available since 1978. Reconstructions of past variability typically rely on sunspot data. However, sunspot records provide only indirect information on the facular and network regions, which are decisive contributors to irradiance variability on timescales of the solar cycle and longer.Aims.Our ultimate goal is to reconstruct past solar irradiance variations using historical full-disc Ca IIK observations to describe the facular contribution independently of sunspot observations. Here, we develop the method and test it extensively by using modern CCD-based (charge-coupled device) Ca IIK observations. We also carry out initial tests on two photographic archives.Methods.We employ carefully reduced and calibrated Ca IIK images from 13 datasets, including some of the most prominent series, such as those from the Meudon, Mt Wilson, and Rome observatories. We convert them to unsigned magnetic field maps and then use them as input to the adapted Spectral and Total Irradiance Reconstruction (SATIRE) model to reconstruct total solar irradiance (TSI) variations over the period 1978–2019, for which direct irradiance measurements are available.Results.The reconstructed irradiance from the analysed Ca IIK archives agrees well with direct irradiance measurements and existing reconstructions. The model also returns good results on data taken with different bandpasses and images with low spatial resolution. Historical Ca IIK archives suffer from numerous inconsistencies, but we show that these archives can still be used to reconstruct TSI with reasonable accuracy provided the observations are accurately processed and the effects of changes in instrumentation and instrumental parameters are identified and accounted for. The reconstructions are relatively insensitive to the TSI reference record used to fix the single free parameter of the model. Furthermore, even employment of a series, itself reconstructed from Ca IIK data, as a reference for further reconstructions returns nearly equally accurate results. This will enable the Ca IIK archives without an overlap with direct irradiance measurements to be used to reconstruct past irradiance.Conclusions.By using the unsigned magnetic maps of the Sun reconstructed from modern high-quality Ca IIK observations as input into the SATIRE model, we can reconstruct solar irradiance variations nearly as accurately as from directly recorded magnetograms. Historical Ca IIK observations can also be used for past irradiance reconstructions but need additional care, for example identifying and accounting for discontinuities and changes in the quality of the data with time.
HD 22496 b: The first ESPRESSO stand-alone planet discovery
Authors: Lillo-Box J. , Faria J. P. , Suárez Mascareño A. , Figueira P. , Sousa S. G. , Tabernero H. , Lovis C. , Silva A. M. , Demangeon O. D. S. , Benatti S. , Santos N. C. , Mehner A. , Pepe F. A. , Sozzetti A. , Zapatero Osorio M. R. , González Hernández J. I. , Micela G. , Hojjatpanah S. , Rebolo R. , Cristiani S. , Adibekyan V. , Allart R. , Allende Prieto C. , Cabral A. , Damasso M. , Di Marcantonio P. , Lo Curto G. , Martins C. J. A. P. , Megevand D. , Molaro P. , Nunes N. J. , Pallé E. , Pasquini L. , Poretti E. , Udry S. 
Published: September 2021

Context. The ESPRESSO spectrograph is a new powerful tool developed to detect and characterize extrasolar planets. Its design allows an unprecedented radial velocity precision (down to a few tens of cm s−1) and long-term thermomechanical stability.
Aims. We present the first stand-alone detection of an extrasolar planet by blind radial velocity search using ESPRESSO; our aim is to show the power of the instrument in characterizing planetary signals at different periodicities in long observing time spans.
Methods. We used 41 ESPRESSO measurements of HD 22496 obtained within a time span of 895 days with a median photon noise of 18 cm s−1. A radial velocity analysis was performed to test the presence of planets in the system and to account for the stellar activity of this K5-K7 main-sequence star. For benchmarking and comparison, we attempted the detection with 43 archive HARPS measurements and in this work we compare the results yielded by the two datasets. We also used four TESS sectors to search for transits.
Results. We find radial velocity variations compatible with a close-in planet with an orbital period of P = 5.09071 ± 0.00026 days when simultaneously accounting for the effects of stellar activity on longer timescales (Prot = 34.99−0.53+0.58 days). We characterize the physical and orbital properties of the planet and find a minimum mass of 5.57−0.68+0.73 M⊕, right in the dichotomic regime between rocky and gaseous planets. Although not transiting according to TESS data, if aligned with the stellar spin axis, the absolute mass of the planet must be below 16 M⊕. We find no significant evidence for additional signals in the data with semi-amplitudes above 56 cm s−1 at 95% confidence.
Conclusions. With a modest set of radial velocity measurements, ESPRESSO is capable of detecting and characterizing low-mass planets and constraining the presence of planets in the habitable zone of K dwarfs down to the rocky-mass regime.
‘I Wish Someone Would Ask Me Questions’: The Unheard Voices of Adolescents with Disabilities in Jordan
Authors: Odeh Kifah Bani , Jones Nicola , Pincock Kate , Malachowska Agnieszka 
Published: September 2021

AbstractThe Sustainable Development Goals and the Leave No One Behind agenda involve a commitment to ensure the participation of persons with disabilities in all aspects of family and community life. This article explores the experiences of Palestinian and Syrian refugee adolescents with disabilities in Jordan in two domains of life: access to education, and their capacity to exercise voice and agency. The findings show that disability intersects with citizenship status and place of residence (camp vs village or city alongside the host community) to reinforce marginality for certain groups of adolescents with disabilities. Across the board, we find low educational aspirations and learning outcomes among adolescents with disabilities, and markedly lower social connectivity—but greater risk of violence by peers. To address these unequal outcomes, we reflect on the importance of developing more inclusive formal and non-formal education services to promote the participation of adolescents with disabilities, and investments in better training and awareness raising for parents, teachers and peers alike.
Mapping out-of-school adolescents and youths in low- and middle-income countries
Authors: Alegana V. A. , Pezzulo C. , Tatem A. J. , Omar B. , Christensen A. 
Published: September 2021

AbstractEducation is a human right and a driver of development, but, is still not accessible for a vast number of adolescents and school-age-youths. Out-of-school adolescents and youth rates (SDG 4.3.1) in lower and middle-income countries have been at a virtual halt for almost a decade. Thus, there is an increasing need to understand geographic variation on accessibility and school attendance to aid in reducing inequalities in education. Here, the aim was to estimate physical accessibility and secondary school non-attendance amongst adolescents and school-age youths in Tanzania, Cambodia, and the Dominican Republic. Community cluster survey data were triangulated with the spatial location of secondary schools, non-proprietary geospatial data and fine-scale population maps to estimate accessibility to all levels of secondary school education and the number of out-of-school. School attendance rates for the three countries were derived from nationally representative household survey data, and a Bayesian model-based geostatistical framework was used to estimate school attendance at high resolution. Results show a sub-national variation in accessibility and secondary school attendance rates for the three countries considered. Attendance was associated with distance to the nearest school (R2 > 70%). These findings suggest increasing the number of secondary schools could reduce the long-distance commuted to school in low-income and middle-income countries. Future work could extend these findings to fine-scale optimisation models for school location, intervention planning, and understanding barriers associated with secondary school non-attendance at the household level.
Injection-seeded terahertz-wave parametric generator with timing stabilized excitation for nondestructive testing applications
Authors: Minamide Hiroaki , Nawata Kouji , Moriguchi Yoshikiyo , Takida Yuma , Notake Takashi 
Published: September 2021

An injection-seeded terahertz (THz)-wave parametric generator (is-TPG) with a footprint the size of an A3 paper is presented. We improved the measurement performance of the is-TPG source for nondestructive inspection applications. A high pulse repetition rate up to 70 kHz and a low pulse timing jitter of a few tens of picoseconds, which is approximately one ten-thousandth of the conventional is-TPG, were achieved. THz waves exhibited excellent performance with a maximum average output power of 20 µW, a monochromatic spectrum linewidth of ∼20 GHz, and a frequency tuning range of 1.7–3.0 THz. This was achieved by designing the entire system configuration from the pump laser source to THz-wave generation. A new double-pass all-solid-state optical amplifier was developed with a high gain and low noise using an externally pulse-modulated laser diode (LD) as the master oscillator source. An achromatic optical injection system was developed for the is-TPG with a 40% reduction in the conventional path length. They were housed in a single enclosure in two layers. LDs and optical fiber amplifiers could be rack-mounted, and the outputs were delivered to the housing via optical fibers. The developed THz-wave source performed nondestructive imaging of a human hair sample fixed with Scotch tape on a test pattern in an envelope by irradiating 2.1 THz waves. A clearly recognizable THz-wave image of an enclosed hair with a spatial resolution close to the THz wavelength was obtained.
Efficient implementations of the symmetric and asymmetric triple excitation corrections for the orbital-optimized coupled-cluster doubles method with the density-fitting approximation
Authors: Alagöz Yavuz , Ünal Aslı , Bozkaya Uğur 
Published: September 2021

Efficient implementations of the symmetric and asymmetric triple excitation corrections for the orbital-optimized coupled-cluster doubles (OCCD) method with the density-fitting approach, denoted by DF-OCCD(T) and DF-OCCD(T)Λ, are presented. The computational cost of the DF-OCCD(T) method is compared with that of the conventional OCCD(T). In the conventional OCCD(T) and OCCD(T)Λ methods, one needs to perform four-index integral transformations at each coupled-cluster doubles iterations, which limits its applications to large chemical systems. Our results demonstrate that DF-OCCD(T) provides dramatically lower computational costs compared to OCCD(T), and there are more than 68-fold reductions in the computational time for the C5H12 molecule with the cc-pVTZ basis set. Our results show that the DF-OCCD(T) and DF-OCCD(T)Λ methods are very helpful for the study of single bond-breaking problems. Performances of the DF-OCCD(T) and DF-OCCD(T)Λ methods are noticeably better than that of the coupled-cluster singles and doubles with perturbative triples [CCSD(T)] method for the potential energy surfaces of the molecules considered. Specifically, the DF-OCCD(T)Λ method provides dramatic improvements upon CCSD(T), and there are 8–14-fold reductions in nonparallelity errors. Overall, we conclude that the DF-OCCD(T)Λ method is very promising for the study of challenging chemical systems, where the CCSD(T) fails.
High frequency of an otherwise rare phenotype in a small and isolated tiger population
Authors: Sagar Vinay , Kaelin Christopher B. , Natesh Meghana , Reddy P. Anuradha , Mohapatra Rajesh K. , Chhattani Himanshu , Thatte Prachi , Vaidyanathan Srinivas , Biswas Suvankar , Bhatt Supriya , Paul Shashi , Jhala Yadavendradev V. , Verma Mayank M. , Pandav Bivash , Mondol Samrat , Barsh Gregory S. , Swain Debabrata , Ramakrishnan Uma 
Published: September 2021

SignificanceSmall and isolated populations have low genetic variation due to founding bottlenecks and genetic drift. Few empirical studies demonstrate visible phenotypic change associated with drift using genetic data in endangered species. We used genomic analyses of a captive tiger pedigree to identify the genetic basis for a rare trait, pseudomelanism, in tigers. Genome sequencing and extensive genotyping of noninvasive samples across tiger range revealed unique spatial presence of this allele in the Similipal Tiger Reserve, India. Population genetic analyses confirmed that Similipal is a small and isolated population. Simulations suggest that intense founding bottlenecks could result in the observed patterns, implicating drift. Our study highlights ongoing phenotypic evolution, potentially from human-induced fragmentation, in endangered large carnivore populations.
Restoring fertility in yeast hybrids: Breeding and quantitative genetics of beneficial traits
Authors: Naseeb Samina , Visinoni Federico , Hu Yue , Hinks Roberts Alex J. , Maslowska Agnieszka , Walsh Thomas , Smart Katherine A. , Louis Edward J. , Delneri Daniela 
Published: September 2021

Significance
Interspecies hybrids, for which mules are a common example, are sterile and therefore an evolutionary dead end. Hybrid sterility has been an obstacle to classical genetic analysis, predictive quantitative approaches, and attempts at strain improvement via breeding. Here, we overcame infertility by creating hybrid tetraploids of yeast species to allow continuous multigenerational breeding. Thus, by exploiting interspecific genetic diversity, we were able to create an unprecedented number of meiotic progenies with different combinations of traits. We showed that the offspring of different hybrids have extreme phenotypes, identified quantitative trait loci (QTLs) dependent of the mitochondria, and discovered QTLs that are uniquely generated in hybrids and for which the allelic variation has no phenotypic consequences in the parental species.
Postmortem memory of public figures in news and social media
Authors: West Robert , Leskovec Jure , Potts Christopher 
Published: September 2021

SignificanceWho is remembered by society after they die? Although scholars as well as the broader public have speculated about this question since ancient times, we still lack a detailed understanding of the processes at work when a public figure dies and their media image solidifies and is committed to the collective memory. To close this gap, we leverage a comprehensive 5-y dataset of online news and social media posts with millions of documents per day. By tracking mentions of thousands of public figures during the year following their death, we reveal and model the prototypical patterns and biographic correlates of postmortem media attention, as well as systematic differences in how the news vs. social media remember deceased public figures.
Remediating the culture industry
Authors: Thomas Jade 
Published: September 2021

Abstract
This article examines to what dramaturgical effect Sam Shepard’s political play States of Shock
(1991) remediates strategies associated with the culture industry. In plays, spectators forge an interpretation from a medium that
is considered ‘hypermedial’ or capable of combining discrete signifying systems such as dialogue, costumes, acting style and scenography at the same time. In States of Shock, genre remediation implicates its audience in the
spectacle of war by juxtaposing American war heroism and military ideology with entertaining vaudeville. By examining Shepard’s
appropriation of the vaudeville genre in relation to other dramatic signifying systems, the article offers a new and more layered
reading of the play’s supposedly ‘blatant’ political message.
Farm animal welfare in the Nigerian context.
Authors: Aworh-Ajumobi Mabel 
Published: September 2021

Abstract

This chapter covers ways to improve livestock in low-income areas such as Nigeria with the help of its government overcoming various challenges. Highlights focused on case studies which includes: better welfare practices for polo horses; training farmers on good animal welfare practices; and how to change the behaviour of cattle farmers in Nigeria and other African countries. The chapter also features the work and life in Nigeria of Dr Aworh-Ajumobi, he works as a government veterinarian at the Federal Ministry of Agriculture and Rural Development in Abuja.
Strengthening existing healthcare systems for sustainable animal welfare.
Authors: Williams Shereene , Skippen Laura 
Published: September 2021

Abstract

More can be achieved by working with what is already in place, compared with creating new systems that undermine local systems and traditions. However, creating lasting improvements in animal health systems at a national level is an ambitious task. Last-mile human healthcare is a key issue in the drive to achieve universal health coverage for all people and looking to the ways that humanitarian agencies are trying to achieve this will be key in driving this forwards for all animals in the future. To push animal welfare up the global agenda and create a catalyst for change, referencing solely animal welfare is not enough. Drawing on linkages between people, the planet and animals is essential.