bluuebunny/crossref_metadata_2025 huggingface dataset:
The Response of Black Hole Spark Gaps to External Changes: A Production Mechanism of Rapid TeV Flares?
Authors: Kisaka Shota , Levinson Amir , Toma Kenji , Niv Idan
Published: January 2022

We study the response of a starved Kerr black hole magnetosphere to abrupt changes in the intensity of disk emission and in the global magnetospheric current, by means of one-dimensional general relativistic particle-in-cell simulations. Such changes likely arise from the intermittency of the accretion process. We find that in cases where the pair-production opacity contributed by the soft disk photons is modest, as in, e.g., M87, such changes can give rise to delayed, strong teraelectronvolt (TeV) flares, dominated by curvature emission of particles accelerated in the gap. The flare rise time, and the delay between the external variation and the onset of the flare emitted from the outer gap boundary, are of the order of the light-crossing time of the gap. The rapid, large-amplitude TeV flares observed in M87, and perhaps, other active galactic nuclei may be produced by such a mechanism.
Final Moments. I. Precursor Emission, Envelope Inflation, and Enhanced Mass Loss Preceding the Luminous Type II Supernova 2020tlf
Authors: Jacobson-Galán W. V. , Dessart L. , Jones D. O. , Margutti R. , Coppejans D. L. , Dimitriadis G. , Foley R. J. , Kilpatrick C. D. , Matthews D. J. , Rest S. , Terreran G. , Aleo P. D. , Auchettl K. , Blanchard P. K. , Coulter D. A. , Davis K. W. , de Boer T. J. L. , DeMarchi L. , Drout M. R. , Earl N. , Gagliano A. , Gall C. , Hjorth J. , Huber M. E. , Ibik A. L. , Milisavljevic D. , Pan Y.-C. , Rest A. , Ridden-Harper R. , Rojas-Bravo C. , Siebert M. R. , Smith K. W. , Taggart K. , Tinyanont S. , Wang Q. , Zenati Y.
Published: January 2022

We present panchromatic observations and modeling of supernova (SN) 2020tlf, the first normal Type II-P/L SN with confirmed precursor emission, as detected by the Young Supernova Experiment transient survey. Pre-SN activity was detected in riz-bands at −130 days and persisted at relatively constant flux until first light. Soon after discovery, “flash” spectroscopy of SN 2020tlf revealed narrow, symmetric emission lines that resulted from the photoionization of circumstellar material (CSM) shed in progenitor mass-loss episodes before explosion. Surprisingly, this novel display of pre-SN emission and associated mass loss occurred in a red supergiant (RSG) progenitor with zero-age main-sequence mass of only 10–12 M
⊙, as inferred from nebular spectra. Modeling of the light curve and multi-epoch spectra with the non-LTE radiative-transfer code CMFGEN and radiation-hydrodynamical code HERACLES suggests a dense CSM limited to r ≈ 1015 cm, and mass-loss rate of 10−2
M
⊙ yr−1. The luminous light-curve plateau and persistent blue excess indicates an extended progenitor, compatible with an RSG model with R
⋆ = 1100 R
⊙. Limits on the shock-powered X-ray and radio luminosity are consistent with model conclusions and suggest a CSM density of ρ < 2 × 10−16 g cm−3 for distances from the progenitor star of r ≈ 5 × 1015 cm, as well as a mass-loss rate of

M

̇

<
1.3
×

10

−
5

M

☉

yr

−
1

at larger distances. A promising power source for the observed precursor emission is the ejection of stellar material following energy disposition into the stellar envelope as a result of gravity waves emitted during either neon/oxygen burning or a nuclear flash from silicon combustion.
The PHANGS-HST Survey: Physics at High Angular Resolution in Nearby Galaxies with the Hubble Space Telescope
Authors: Lee Janice C. , Whitmore Bradley C. , Thilker David A. , Deger Sinan , Larson Kirsten L. , Ubeda Leonardo , Anand Gagandeep S. , Boquien Médéric , Chandar Rupali , Dale Daniel A. , Emsellem Eric , Leroy Adam K. , Rosolowsky Erik , Schinnerer Eva , Schmidt Judy , Lilly James , Turner Jordan , Van Dyk Schuyler , White Richard L. , Barnes Ashley T. , Belfiore Francesco , Bigiel Frank , Blanc Guillermo A. , Cao Yixian , Chevance Melanie , Congiu Enrico , Egorov Oleg V. , Glover Simon C. O. , Grasha Kathryn , Groves Brent , Henshaw Jonathan D. , Hughes Annie , Klessen Ralf S. , Koch Eric , Kreckel Kathryn , Kruijssen J. M. Diederik , Liu Daizhong , Lopez Laura A. , Mayker Ness , Meidt Sharon E. , Murphy Eric J. , Pan Hsi-An , Pety Jérôme , Querejeta Miguel , Razza Alessandro , Saito Toshiki , Sánchez-Blázquez Patricia , Santoro Francesco , Sardone Amy , Scheuermann Fabian , Schruba Andreas , Sun Jiayi , Usero Antonio , Watkins E. , Williams Thomas G.
Published: January 2022

The PHANGS program is building the first data set to enable the multiphase, multiscale study of star formation across the nearby spiral galaxy population. This effort is enabled by large survey programs with the Atacama Large Millimeter/submillimeter Array (ALMA), MUSE on the Very Large Telescope, and the Hubble Space Telescope (HST), with which we have obtained CO(2–1) imaging, optical spectroscopic mapping, and high-resolution UV–optical imaging, respectively. Here, we present PHANGS-HST, which has obtained NUV–U–B–V–I imaging of the disks of 38 spiral galaxies at distances of 4–23 Mpc, and parallel V- and I-band imaging of their halos, to provide a census of tens of thousands of compact star clusters and multiscale stellar associations. The combination of HST, ALMA, and VLT/MUSE observations will yield an unprecedented joint catalog of the observed and physical properties of ∼100,000 star clusters, associations, H ii regions, and molecular clouds. With these basic units of star formation, PHANGS will systematically chart the evolutionary cycling between gas and stars across a diversity of galactic environments found in nearby galaxies. We discuss the design of the PHANGS-HST survey and provide an overview of the HST data processing pipeline and first results. We highlight new methods for selecting star cluster candidates, morphological classification of candidates with convolutional neural networks, and identification of stellar associations over a range of physical scales with a watershed algorithm. We describe the cross-observatory imaging, catalogs, and software products to be released. The PHANGS high-level science products will seed a broad range of investigations, in particular, the study of embedded stellar populations and dust with the James Webb Space Telescope, for which a PHANGS Cycle 1 Treasury program to obtain eight-band 2–21 μm imaging has been approved.
Testing Algorithms for Identifying Source Confusion in the H i-MaNGA Survey
Authors: Shapiro Griffin , Stark David V. , Masters Karen L.
Published: January 2022

Astronomical observations of neutral atomic hydrogen (H i) are an important tracer of several key processes of galaxy evolution, but face significant difficulties with terrestrial telescopes. Among these is source confusion, or the inability to distinguish between emission from multiple nearby sources separated by distances smaller than the telescope’s spatial resolution. Confusion can compromise the data for the primary target if the flux from the secondary galaxy is sufficient. This paper presents an assessment of the confusion-flagging methods of the H i-MaNGA survey, using higher-resolution H i data from the Westorbork Synthesis Radio Telescope-Apertif survey. We find that removing potentially confused observations using a confusion probability metric—calculated from the relationship between galaxy color, surface brightness, and H i content—successfully eliminates all significantly confused observations in our sample, although roughly half of the eliminated observations are not significantly confused.
Abundance Analysis of the J4 Equatorial Knot of the Born-again Planetary Nebula A30
Authors: Simpson Jordan , Jones David , Wesson Roger , García-Rojas Jorge
Published: January 2022

A30 belongs to a class of planetary nebulae identified as “born-again”, containing dense, hydrogen-poor ejecta with extreme abundance discrepancy factors (ADFs), likely associated with a central binary system. We present intermediate-dispersion spectroscopy of one such feature—the J4 equatorial knot. We confirm the apparent physical and chemical segregation of the polar and equatorial knots observed in previous studies, and place an upper limit on the ADF for O2+ of 35, significantly lower than that of the polar knots. These findings further reinforce the theory that the equatorial and polar knots originate from different events.
128383 (2004 JW52) is an Ordinary Jupiter Trojan Asteroid
Authors: Seccull Tom
Published: January 2022

The Jupiter Trojan asteroid 128383 (2004 JW52) was recently reported to have optical colors that are incongruous with its dynamical class. New and archival observations show that this is not the case. This is a reminder that we must always rule out the possibility that the Point-Spread Function of a minor planet is blended with that of a background sidereal source in survey images before its colors in the associated survey catalog can be considered reliable.
Determining Research Priorities for Astronomy Using Machine Learning
Authors: Thomas Brian , Thronson Harley , Buonomo Anthony , Barbier Louis
Published: January 2022

We summarize the first exploratory investigation into whether Machine Learning techniques can augment science strategic planning. We find that an approach based on Latent Dirichlet Allocation using abstracts drawn from high-impact astronomy journals may provide a leading indicator of future interest in a research topic. We show two topic metrics that correlate well with the high-priority research areas identified by the 2010 National Academies’ Astronomy and Astrophysics Decadal Survey. One metric is based on a sum of the fractional contribution to each topic by all scientific papers (“counts”) while the other is the Compound Annual Growth Rate of counts. These same metrics also show the same degree of correlation with the whitepapers submitted to the same Decadal Survey. Our results suggest that the Decadal Survey may under-emphasize fast growing research. A preliminary version of our work was presented by Thronson et al.
Stars on the Verge: Analyses of the Complex Light Variations of the Hyper-luminous Red Supergiant VY Canis Majoris: On the Nature of the Star’s “Great Dimming” Episodes
Authors: Nguyen Thinh H. , Guinan Edward F.
Published: January 2022

VY Canis Majoris (VY CMa) is one of the largest, most luminous red supergiant (RSG) stars in the Galaxy. This huge oxygen-rich RSG may be on the verge of becoming a bright core-collapse Type-II supernova. Over the 20th century, VY CMa has been undergoing episodic large quasi-periodic light variations. It has experienced two “great dimming” episodes during ∼1920–1950 and ∼1985–1995. During these, the star underwent large (1–2.5 mag) quasi-periodic light variations with dominant periods ranging between ∼1415 and 1565 days. In addition to experiencing large quasi-periodic light variations, VY CMa became fainter by 1.0–1.5 mag during the 1920–1950 episode. There is evidence that the star’s brightness decreased from ∼6.5–7.0 to ∼8.0–8.5 mag from 1850 to after 1900. These long-term dimming events may arise from dust formation from previously expelled gas. The light variations and the “dimmings” of VY CMa far surpass the recent “great dimming” of Betelgeuse.
Volatile Abundances, Extended Coma Sources, and Nucleus Ice Associations in Comet C/2014 Q2 (Lovejoy)
Authors: Dello Russo Neil , Vervack Ronald J. , Kawakita Hideyo , Bonev Boncho P. , DiSanti Michael A. , Gibb Erika L. , McKay Adam J. , Cochran Anita L. , Weaver Harold A. , Biver Nicolas , Crovisier Jacques , Bockelée-Morvan Dominique , Kobayashi Hitomi , Harris Walter M. , Roth Nathan X. , Saki Mohammad , Khan Younas
Published: January 2022

High-resolution infrared spectra of comet C/2014 Q2 Lovejoy were acquired with NIRSPEC at the W. M. Keck Observatory on two post-perihelion dates (UT 2015 February 2 and 3). H2O was measured simultaneously with CO, CH3OH, H2CO, CH4, C2H6, C2H4, C2H2, HCN, and NH3 on both dates, and rotational temperatures, production rates, relative abundances, H2O ortho-to-para ratios, and spatial distributions in the coma were determined. The first detection of C2H4 in a comet from ground-based observations is reported. Abundances relative to H2O for all species were found to be in the typical range compared with values for other comets in the overall population to date. There is evidence of variability in rotational temperatures and production rates on timescales that are small compared with the rotational period of the comet. Spatial distributions of volatiles in the coma suggest complex outgassing behavior. CH3OH, HCN, C2H6, and CH4 spatial distributions in the coma are consistent with direct release from associated ices in the nucleus and are peaked in a more sunward direction compared with co-measured dust. H2O spatial profiles are clearly distinct from these other four species, likely due to a sizable coma contribution from icy grain sublimation. Spatial distributions for C2H2, H2CO, and NH3 suggest substantial contributions from extended coma sources, providing further evidence for distinct origins and associations for these species in comets. CO shows a different spatial distribution compared with other volatiles, consistent with jet activity from discrete nucleus ice sources.
Magnetospheric Ion Bombardment of Europa’s Surface
Authors: Nordheim T. A. , Regoli L. H. , Harris C. D. K. , Paranicas C. , Hand K. P. , Jia X.
Published: January 2022

Jupiter’s moon Europa is exposed to constant bombardment by magnetospheric charged particles, which are expected to be a major source of physical and chemical surface modification. Here we have investigated the flux of magnetospheric ions at Europa’s surface by carrying out single particle tracing within realistic electromagnetic fields from multifluid magnetohydrodynamic simulations of the moon’s interaction with Jupiter’s magnetosphere. We find that magnetic field line draping and pileup leads to shielding and drastically reduced flux at low latitudes across Europa’s trailing (upstream) hemisphere. Furthermore, we find that magnetic induction within Europa’s subsurface ocean leads to additional shielding when the moon is located at high magnetic latitudes in Jupiter’s magnetosphere. Overall, we find that the high-latitude and polar regions on Europa receive the largest flux of magnetospheric ions. Both spacecraft and ground-based observations have previously identified a non–water ice surface species concentrated at Europa’s trailing (upstream) hemisphere, possibly hydrated sulfuric acid formed from radiolysis of water ice with implanted S ions. Our results demonstrate that the S ion flux across Europa’s equatorial trailing (upstream) hemisphere is strongly reduced, possibly indicating that the formation of the observed non–water ice species is controlled primarily by energy input from magnetospheric electrons, rather than the flux of S ions. We find that that O and S ions at >1 MeV energies have nearly uniform access to the surface, while energetic protons in this energy range are constrained to a “bull’s-eye” centered on the trailing (upstream) hemisphere.
Dissecting the illegal pangolin trade in China: An insight from seizures data reports
Authors: Omifolaji James Kehinde , Hughes Alice C. , Ibrahim Abubakar Sadiq , Zhou Jinfeng , Zhang Siyuan , Ikyaagba Emmanuel Tersea , Luan Xiaofeng
Published: January 2022

Wildlife trafficking poses a major threat to global biodiversity. Species such as pangolins are particularly vulnerable and trade continues almost unabated despite numerous interventions aimed at eradicating illegal wildlife trade. Despite restrictions on the pangolin trade, thousands of pangolins continue to be intercepted annually. We focused on China because of the recent delisting of pangolins from the Chinese pharmacopeia, and their removal from healthcare insurance, despite deeply ingrained traditions of having pangolins for ethno-medicinal use. We collated pangolin interception data from public online media seizure reports to characterize the pangolin trade within China, and found that a total of 326 independent seizures equivalent to 143,130 pangolins (31,676 individuals and 222,908 kg of scale) were reported in 26 provinces. Pangolin domestic seizures are greatest in the southern cities of Dehong, Fangchenggang, and Guangzhou. Also, we found 17 countries within the global pangolins range which were the major source of the pangolin shipments to China. The number of arrests and convictions was much lower than the number of pangolin incidents reported. Our results show a significant increase in the volume of scales and number of live pangolin seizures after amended endangered species law came into effect in 2018, and recorded the highest number of individual pangolin interceptions. China has shown increasing wildlife seizures over time, owing partly to emergent trends in the international wildlife trade as well as increasing global demand for ethnomedicine. The future eradication of illegal wildlife trade in China is dependent not only on stringent border control and offender prosecution but also the; removal of other threatened species from the pharmacopeia and healthcare insurance which includes wildlife derivatives. Furthermore, our work highlights importance of current policy intervention to combat the pangolin trade within China, and the need for further interventions both within China and in export countries.
Le triage, un enjeu éthique de la pandémie de la Covid‑19. Constats et questionnements autour d’un impensé
Authors: Mongiat-Artus Pierre , Lefève Céline , Legeais Didier , Lechevallier Éric , Castagnola Christian , de l’Association Française d’Urolog Le Comité d’Éthique et de Déon
Published: January 2022

Cet article se consacre aux questions éthiques posées par le triage durant la pandémie de Covid-19 en France. Il rappelle le contexte d’apparition de ces questions lors de la pandémie ainsi que les définitions du triage et ses principaux enjeux éthiques. Il décrit ensuite les terrains médicaux où un triage s’est déployé. Il montre les impensés épistémiques, politiques et éthiques qui entourent cette question en France. Il met enfin en regard de ces impensés des jalons visant à co-construire la réflexion éthique en la matière et se préparer à gérer les crises actuelles et futures.
Comparison of eleven measures for estimating difficulty of open-loop TSP instances
Authors: Sengupta Lahari ,   Machine Learning, School of Computing, University of Eastern Finland, Finland, Fränti Pasi
Published: January 2022

From the theory of algorithms, we know that the time complexity of finding the optimal solution for a traveling salesman problem (TSP) grows exponentially with the number of targets. However, the size of the problem instance is not the only factor that affects its difficulty. In this paper, we review existing measures to estimate the difficulty of a problem instance. We also introduce MST branches and two other measures called greedy path and greedy gap. The idea of MST branches is to generate minimum spanning tree (MST) and then calculate the number of branches in the tree. A branch is a target, which is connected to at least two other targets. We perform an extensive comparison of 11 measures to see how well they correlate to human and computer performance. We evaluate the measures based on time complexity, prediction capability, suitability, and practicality. The results show that while the MST branches measure is simple, fast to compute, and does not need to have the optimal solution as a reference unlike many other measures. It correlates equally good or even better than the best of the previous measures ‑ the number of targets, and the number of targets on the convex hull.
Can synoptic patterns influence the track and formation of tropical cyclones in the Mozambique Channel?
Authors: Ibebuchi Chibuike Chiedozie ,   Institute of Geography and Geology, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
Published: January 2022

The influence of large-scale circulation patterns on the track and formation of tropical cyclones (TCs) in the Mozambique Channel is investigated in this paper. The output of the hourly classification of circulation types (CTs), in Africa, south of the equator, using rotated principal component analysis on the T-mode matrix (variable is time series and observation is grid points) of sea level pressure (SLP) from ERA5 reanalysis from 2010 to 2019 was used to investigate the time development of the CTs at a sub-daily scale. The result showed that at specific seasons, certain CTs are dominant so that their features overlap with other CTs. CTs with synoptic features, such as enhanced precipitable water and cyclonic activity in the Mozambique Channel that can be favorable for the development of TC in the Channel were noted. The 2019 TC season in the Mozambique Channel characterized by TC Idai in March and TC Kenneth afterward in April were used in evaluating how the CTs designated to have TC characteristics played role in the formation and track of the TCs towards their maximum intensity. The results were discussed and it generally showed that large-scale circulation patterns can influence the formation and track of the TCs in the Mozambique Channel especially through (ⅰ) variations in the position and strength of the anticyclonic circulation at the western branch of the Mascarene high; (ⅱ) modulation of wind speed and wind direction; hence influencing convergence in the Channel; (ⅲ) and modulation of the intensity of cyclonic activity in the Channel that can influence large-scale convection.
An adaptive large neighborhood search heuristic for multi-commodity two-echelon vehicle routing problem with satellite synchronization
Authors: Jia Shengyang , Deng Lei , Zhao Quanwu , Chen Yunkai
Published: January 2022

In considering route optimization from multiple distribution centers called depots via some intermediate facilities called satellites to final customers with multiple commodities request, we introduce the Multi-Commodity Two-Echelon Vehicle Routing Problem with Satellite Synchronization (MC-2E-VRPSS). The MC-2E-VRPSS involves the transportation from multiple depots to satellites on the first echelon and the deliveries from satellites to final customers on the second echelon. The MC-2E-VRPSS integrates satellite synchronization constraints and time window constraints for satellites on the two-echelon network and aims to determine cost-minimizing routes for the two echelons. The satellite synchronization constraints which trucks from the multiple depots to some satellites need to be coordinated guarantee the efficiency of the second echelon network. In this study, we develop a mixed-integer programming model for the MC-2E-VRPSS. For validating the model formulation, we conduct the computational experiments on a set of small-scale instances using GUROBI and an adaptive large neighborhood search (ALNS) heuristic which we develop for the problem. Furthermore, the computation experiments for evaluating the applicability of the ALNS heuristic compared with large neighborhood search (LNS) on a set of large-scale instances are also conducted, which proved the effectiveness of the ALNS.

 

Addendum: The Acknowledgement “This study was supported by the Humanities and Social Sciences Foundation Program of the Ministry of Education (Project No.19YJA630122), and the "National Key R&D Program of China"(Grant No.2020YFB1712900)” is added. We apologize for any inconvenience this may cause.
Existence of stable standing waves for the nonlinear Schrödinger equation with attractive inverse-power potentials
Authors: Meng Yali ,   Department of Mathematics, Northwest Normal University, Lanzhou 730070, China
Published: January 2022

In this paper, we consider the following nonlinear Schrödinger equation with attractive inverse-power potentials

   \begin{document}$ i\partial_t\psi+\Delta\psi+\gamma|x|^{-\sigma}\psi+|\psi|^\alpha\psi = 0, \; \; \; (t, x)\in\mathbb{R}\times\mathbb{R}^N, $\end{document}

where $ N\geq3 $, $ 0 < \gamma < \infty $, $ 0 < \sigma < 2 $ and $ \frac{4}{N} < \alpha < \frac{4}{N-2} $. By using the concentration compactness principle and considering a local minimization problem, we prove that there exists a $ \gamma_0 > 0 $ sufficiently small such that $ 0 < \gamma < \gamma_0 $ and for any $ a\in(0, a_0) $, there exist stable standing waves for the problem in the $ L^2 $-supercritical case. Our results are complement to the result of Li-Zhao in [23].
Existence, uniqueness and strict comparison theorems for BSDEs driven by RCLL martingales
Authors: Nie Tianyang , Rutkowski Marek
Published: January 2022

The existence, uniqueness, and strict comparison for solutions to a BSDE driven by a multi-dimensional RCLL martingale are developed. The goal is to develop a general multi-asset framework encompassing a wide spectrum of non-linear financial models with jumps, including as particular cases, the setups studied by Peng and Xu [27, 28] and Dumitrescu et al. [7] who dealt with BSDEs driven by a one-dimensional Brownian motion and a purely discontinuous martingale with a single jump.
CVaR-hedging and its applications to equity-linked life insurance contracts with transaction costs
Authors: Melnikov Alexander , Wan Hongxi
Published: January 2022

This paper analyzes Conditional Value-at-Risk (CVaR) based partial hedging and its applications on equity-linked life insurance contracts in a Jump-Diffusion market model with transaction costs. A nonlinear partial differential equation (PDE) that an option value process inclusive of transaction costs should satisfy is provided. In particular, the closed-form expression of a European call option price is given. Meanwhile, the CVaR-based partial hedging strategy for a call option is derived explicitly. Both the CVaR hedging price and the weights of the hedging portfolio are based on an adjusted volatility. We obtain estimated values of expected total hedging errors and total transaction costs by a simulation method. Furthermore,our results are implemented to derive target clients’ survival probabilities and age of equity-linked life insurance contracts.
La representación de la vida cotidiana de las mujeres de las clases bajas en los libros de adab: aproximación a partir de un ejemplar de época nazarí (s. VIII/XIV)
Authors: López-Bernal Desirée
Published: January 2022

El objetivo del presente trabajo es rastrear en los libros de adab imágenes literarias de la vida cotidiana de las mujeres árabes-musulmanas de las clases bajas en entornos urbanos, puestas en relación con los conocimientos que poseemos al respecto a partir de fuentes de otra naturaleza. El estudio se ha llevado a cabo tomando como fuente principal un ejemplar del periodo nazarí, los Ḥadāʾiq al-azāhir de Ibn ʿĀṣim. No obstante, con el fin de ofrecer un panorama más amplio, la investigación se apoya necesariamente en otras obras del género del periodo premoderno, compuestas en distintas épocas y lugares. En conjunto, aportamos una serie de textos y referencias no utilizados hasta ahora en estudios sobre el tema. Tras su análisis, se obtiene que las representaciones literarias que ofrecen sus anécdotas confirman la información en las diversas parcelas que comprende el tema objeto de estudio obtenida hasta el momento de fuentes históricas o tratados de derecho o ḥisba. Al mismo tiempo, estas obras literarias presentan un elevado interés en tanto que la mayoría de personajes femeninos que aparecen en sus anécdotas pertenecen a las clases populares y en ellas se representan sus comportamientos en la vida cotidiana. En la prosa de adab, apenas se transmite una separación entre espacios masculinos y femeninos en las ciudades. Los relatos muestran a aquellas mujeres realizando diversas actividades fuera del ámbito doméstico y nos acercan a las relaciones que establecieron con los hombres desde dentro y fuera de sus viviendas.
A Review of AI (Artificial Intelligence) Tools and Customer Experience in Online Fashion Retail
Authors: Pillarisetty Radhika , Mishra Pratika
Published: January 2022

Artificial Intelligence tools and processes have hugely impacted the ecommerce industry and the satisfaction of online customers. With technology largely pervading all facets of our lives, people want meaningful experiences. Artificial intelligence has the ability to deliver positive experiences for customers that helps build brand trust and customer satisfaction. Whether you are using your smartphone, laptop or voice assistants such as Alexa or Siri, service on the internet is gaining new ground. This paper does a literature review of the various technological advances that optimize the customer experience to evoke e-satisfaction, i.e. satisfaction while shopping online. E-satisfaction as a construct will be reviewed and its impact on customer purchase intention. This review will provide businesses and other researchers a frame of reference to conduct empirical studies in the area of AI and technology enabled retail.
Failure Prediction Approach in Agile Software Development
Authors: Alajaleen Bulqees , Alhroob Aysh
Published: January 2022

Software failure prediction is an important activity during agile software development as it can help managers to identify the failure modules. Thus, it can reduce the test time, cost and assign testing resources efficiently. RapidMiner Studio9.4 has been used to perform all the required steps from preparing the primary data to visualizing the results and evaluating the outputs, as well as verifying and improving them in a unified environment. Two datasets are used in this work, the results for the first one indicate that the percentage of failure to predict the time used in the test is for all 181 rows, for all test times recorded, is 3% for Mean time between failures (MTBF). Whereas, SVM achieved a 97% success in predicting compared to previous work whose results indicated that the use of Administrative Delay Time (ADT) achieved a statistically significant overall success rate of 93.5%. At the same time, the second dataset result indicates that the percentage of failure to predict the time used is 1.5% for MTBF, SVM achieved 98.5% prediction.
Effects of Safety Zone Implementation on Perceptions of Safety and Well-being When Caring for COVID-19 Patients
Authors: Skinner Claudia , Ablir Lilian , Bloom Todd , Fujimoto Stacie , Rozenfeld Yelena , Leung Peggy
Published: January 2022

Background

In March 2020, the caseload of patients positive for COVID-19 in hospitals began increasing rapidly, creating fear and anxiety among health care workers and concern about supplies of personal protective equipment.

Objectives

To determine if implementing safety zones improves the perceptions of safety, well-being, workflow, and teamwork among hospital staff caring for patients during a pandemic.

Methods

A safety zone process was implemented to designate levels of contamination risk and appropriate activities for certain areas. Zones were designated as hot (highest risk), warm (moderate risk), or cold (lowest risk). Caregivers working in the safety zones were invited to complete a survey regarding their perceptions of safety, caregiver well-being, workflow, and teamwork. Each question was asked twice to obtain caregiver opinions for the periods before and after implementation of the zones.

Results

Significant improvements were seen in perceptions of caregiver safety (P < .001) and collaboration within a multidisciplinary staff (P < .001). Significant reductions in perceived staff fatigue (P = .03), perceived cross contamination (P < .001), anxiety (P < .001), and fear of exposure (P < .001) were also seen. Teamwork (P = .23) and workflow (P = .69) were not significantly affected.

Conclusions

Safety zone implementation improved caregivers’ perceptions of their safety, their well-being, and collaboration within the multidisciplinary staff but did not improve their perceptions of teamwork or workflow.
Memory Gaps in America: Mutational and Immunoinformatic Analysis of Evolving SARS-CoV-2 Variants of Concern and Interest
Authors: Shakran Dina A , Mikbel Deena M , Vilela Mario F , Benoit Lora A
Published: January 2022

The perpetuation of the SARS-CoV-2 pandemic has permitted the continued evolution of mutations, many of which appear to promote infectivity, transmission, and immune evasion. Critically, several derivative lineages defined as variants of concern (VOCs) and variants of interest (VOIs) have emerged in the last year that possess a constellation of highly adaptive mutations that have resulted in unprecedented propagation. To better understand the significance of these mutations, we analyzed their molecular and immunological consequences against the immunogenetic profile of the United States population using immunoinformatics to analyze in silico data. Our findings indicate that several evolving mutations in the VOCs and VOIs appear to confer immune evasion properties leading to antigenic drift, specifically for Ab-mediated and Th cell–mediated immune recognition, whereas mutations leading to evasion from innate immune mechanisms are less common in the more successful VOC strains compared with the VOIs. Importantly, several of these mutations raise concerns for the effectiveness of anamnestic responses achieved through natural infection and vaccination as well as for the utility of Ab-based therapeutic interventions. The emergence of such adaptations underscores the need for vaccine enhancements as well as the continued need to for preventative hygiene measures to help minimize transmission.
Novel Mouse Model of Murine Cytomegalovirus–Induced Adaptive NK Cells
Authors: Jensen Isaac J , Martin Matthew D , Tripathy Sandeep K , Badovinac Vladimir P
Published: January 2022

NK cells are important mediators of viral control with the capacity to form adaptive immune features following infection. However, studies of infection-induced adaptive NK cells require adoptive cell transfer to lower the precursor frequency of “Ag-specific” NK cells, potentially limiting the diversity of the NK cell response. In seeking an unmanipulated model to probe the adaptive NK cells, we interrogated a wide range of Collaborative Cross (CC) inbred mice, inbred mouse strains that exhibit broad genetic diversity across strains. Our assessment identified and validated a putative “ideal” CC strain, CC006, which does not require manipulation to generate and maintain adaptive NK cells. Critically, CC006 mice, in contrast to C57BL/6 mice, are capable of developing enhanced NK cell–mediated protective responses to murine CMV infection following m157-mediated vaccination. This work both furthers our understanding of adaptive NK cells and demonstrates the utility of CC mice in the development and interrogation of immunologic models.
Systematic Determination of TCR–Antigen and Peptide–MHC Binding Kinetics among Field Variants of a Theileria parva Polymorphic CTL Epitope
Authors: Svitek Nicholas , Saya Rosemary , Zhang Houshuang , Nene Vishvanath , Steinaa Lucilla
Published: January 2022

CTLs are known to contribute to immunity toward Theileria parva, the causative agent of East Coast fever. The Tp967–75 CTL epitope from the Muguga strain of T. parva is polymorphic in other parasite strains. Identifying the amino acids important for MHC class I binding, as well as TCR recognition of epitopes, can allow the strategic selection of Ags to induce cellular immunity toward T. parva. In this study, we characterized the amino acids important for MHC class I binding and TCR recognition in the Tp967–75 epitope using alanine scanning and a series of variant peptide sequences to probe these interactions. In a peptide–MHC class I binding assay, we found that the amino acids at positions 1, 2, and 3 were critical for binding to its restricting MHC class I molecule BoLA-1*023:01. With IFN-γ ELISPOT and peptide–MHC class I Tet staining assays on two parasite-specific bovine CTL lines, we showed that amino acids at positions 5–8 in the epitope were required for TCR recognition. Only two of eight naturally occurring polymorphic Tp9 epitopes were recognized by both CTLs. Finally, using a TCR avidity assay, we found that a higher TCR avidity was associated with a stronger functional response toward one of two variants recognized by the CTL. These data add to the growing knowledge on the cross-reactivity of epitope-specific CTLs and specificities that may be required in the selection of Ags in the design of a wide-spectrum vaccine for East Coast fever.
La malattia da reflusso gastroesofageo nell’ambulatorio di Medicina Interna: quale gestione medica nel 2021?
Authors: Parisi Giancarlo
Published: January 2022

Non disponibile
La traducción literaria como compromiso social y cultural
Authors: Strnadová Karolína
Published: January 2022

Este artículo interpreta el papel del traductor en la génesis de las traducciones de la literatura checa publicadas originalmente en México. Hasta la fecha se publicaron originalmente en México trece títulos de la literatura checa, la mayoría de ellos gracias a la iniciativa del traductor. Aplicando los principios de la arqueología de traducción y basándonos en el análisis de los paratextos y las entrevistas realizadas con los traductores contemporáneos, explicamos el motivo y objetivo de estas traducciones. Desde las distintas perspectivas de la investigación sociológica de traducción nos centramos en el papel del traductor como mediador entre dos culturas, quien de forma deliberada o no deliberada asume la responsabilidad de la mediación socio-cultural entre la cultura de partida y la cultura meta. El estudio sociológico de la creación de las traducciones de la literatura checa en México permite reflexionar sobre la responsabilidad social y cultural de los traductores quienes muchas veces son iniciadores y directores de los proyectos traductológicos y mediadores de la comunicación literaria y cultural entre Chequia y México.
Ethics in translation practice
Authors: Bennett Phillippa May
Published: January 2022

The interest in and understanding of ethics among translation scholars has changed dramatically since the publication of Andrew Chesterman’s proposal for a Hieronymic Oath (Chesterman, 2001). Early definitions of ethics based on equivalence (Newmark, 1991), faithfulness, loyalty (Nord, 1997) and trust have been put aside in favour of more recent notions of translator ethics grounded in accountability (Baker & Maier, 2011) and social responsibility (Drugan & Tipton, 2017). Practising translators who abide by codes of ethics/conduct are bound by principles of honesty, integrity, linguistic competence, confidentiality, and trust. This paper begins by presenting a brief literature review of the main developments in translation ethics from the early linguists to contemporary interpretations. There then follows an analysis and comparison of several professional codes of conduct from the main international associations of translators and interpreters with the benchmark, the Association of Translation and Interpreting Professionals (APTRAD). It is one of the more recent translator associations and has a code of conduct adopted in the last six years. The objective of this paper is to determine which theoretical definitions of ethics are reflected in the codes of conduct and to discuss their usefulness for translators in their daily practice. The paper ends with recommendations for changes to codes of conduct to make them more relevant to practising translators.
Experimental study on the analysis of nanocellulose treated water in Yola metropolis, Nigeria
Authors: Okoro Linus N. , Agboola Bolade O. , Yakubu Precious O.
Published: January 2022

In this study, cellulose from sugarcane bagasse and wood pulp were converted to nanocellulose and utilized to treat water from different sources within Yola Metropolis to study the efficacy of both methods. From the analysed water parameters, both nanocellulose materials were effective in treating contaminated water. They showed the capability of reducing the concentrations of the various tested parameters such as Total Dissolved Solids (TDS), Nitrate, Chloride, and Nephelometric Turbidity Units (NTU). Interestingly, analysis of the heavy metal concentrations before and after water treatment with the nanocellulose, showed very significant reduction of the heavy metals. This is encouraging as we explore more efficient methods of water treatment, in order to tackle rising cases of lead and other heavy metal poisoning in Nigeria due to illegal mining activities and deregulated industrial activities.

Dans cette recherche, la cellulose de la bagasse de canne à sucre et de la pulpe de bois a été converties en nanocellulose et utilisées pour l’épuration d’eau de différentes sources au sein de Yola Metropolis afin d’étudier l’efficacité des deux méthodes. D’après les paramètres d’eau analysés avec les deux types de nanocelluloses étaient efficaces dans le traitement de l’eau contaminée. Ils ont considérablement réduit les concentrations des différents contaminants testés tels que le TDS, le nitrate, le chlorure et le NTU. En effet, l’analyse de la concentration en métaux lourds avant et après le traitement de l’eau avec la nanocellulose a montré une réduction très significative des métaux lourds. C’est une bonne chose car nous explorons des méthodes plus efficaces de traitement de l’eau, pour lutter contre l’augmentation des cas d’empoisonnement au plomb et à d’autres métaux lourds au Nigeria en raison d’activités minières illégales et d’activités industrielles non réglementées.
Impact of climate change on domestic water accessibility in Bamenda III Sub-Division, North West region, Cameroon
Authors: Tume Suiven John Paul
Published: January 2022

The effects of climate change are felt most at the household level, when taps and springs run dry for several weeks or months, forcing people to access potable water from doubtful sources. There has been an increase in the population of Bamenda III without a proportionate increase in the water supply capacity. This has resulted in severe water crises, even though Bamenda III municipality has water supplies from the Council, Community, CAMWATER, natural springs and streams, wells and boreholes. Household data on water accessibility against a backdrop of a changing climate was collected using 269 questionnaires to assess perceptions on the state of water resources and climate. Rainfall data were collected from 1963-2019 and results revealed that mean annual rainfall is at 182.52 mm, with a standard deviation of 29.16 and a Coefficient of Variation of 15.69%, while the mean Standardized Precipitation Index is -0.07 (mild dryness), and rainfall has reduced by -2.07 mm from 1963-2019. The population attributed problems of water accessibility to climate change, urbanization and poor water governance. It is recommended that sustainable water management through Nature-based Solutions and Ecosystem-based Adaptation should be implemented from the watershed to the community level.
Training Needs Assessment for a Bachelor of Science Program in Eye Care at the University of Rwanda
Authors: Kagwiza Jeanne , Ekimiri Kingsley , Mumena Chrispinus , Tumusiime David K. , Fiston Kitema Gatera , Twiringirimana Francois Regis , Uwisunze Marie Josee , Ransford Darko , Uwacu Didier Fidele , Ugirashebuja Swamadu , Ndayambaje Denys
Published: January 2022

BackgroundThe University of Rwanda, established the Ophthalmology Department in 2004 to train Ophthalmic Clinical Officers (OCO). A proposal was developed towards upgrading the qualification level of the OCOs training at the University of Rwanda.AimThis study aimed to assess the need to upgrade the qualification of ophthalmic clinical officers to improve eye health services in Rwanda.MethodologyA descriptive cross-sectional study was conducted among 87 participants comprised of ophthalmic clinical officers, eye health development stakeholders, and employers in Rwanda selected purposively. Data analysis was performed using SPSS version 16.ResultsThe results showed that 77% of participants in the stakeholders group and 51.4% in the OCOs group were males. About 97% (n= 34) of the OCO responded “Yes” to the questions “Do you think some of the weaknesses related to quality practice are related to the level of training?” and “Does your qualification have any effect to your professional development?” Furthermore, 85% had never been promoted at any employment position, 100 % (n=35) alumni and 84 % (n=22) stakeholders agreed that there is a need for bachelor’s degree program.ConclusionThe need for developing new programs in ophthalmology including a Bachelor of Science degree program for OCOs was evident.Rwanda J Med Health Sci 2021;4(3):357-365
Standard Precautions among HealthCare Workers in a Tertiary Health Facility in Enugu Metropolis, South-East Nigeria
Authors: Nwoga Hope , Ajuba Miriam , Chime Onyinye
Published: January 2022

BackgroundThe work environment of Health Care Workers (HCWs) can be described as a potential risk zone due to numerous hazards endemic to the environment. The hospital is not just only a place where the sick people recover from their illness, but also where the healthy get infected.ObjectivesTo assess the knowledge, attitude and practice of Standard Precautions (SP) among HCWs in a tertiary government health facility in Enugu Metropolis, Nigeria.MethodsA descriptive cross-sectional design that used mixed method approach. Qualitative data was collected using an in-depth interview. The quantitative data instrument was a semi-structured, self-administered questionnaire. Manual content analysis was done for the qualitative data. Quantitative data was analysed using SPSS version 22.ResultsSixty-four (32.0%), 131(65.5%) and 5(2.5%) had good, fair and poor knowledge of SP respectively while 117(58.5%), 70(35.0%) and 13(6.5%) had good, fair and poor attitude to SP respectively. Fifty-nine (29.5%), 140(70.0%) and 1(0.5%) had good, fair and poor practice of SP respectively.ConclusionThere was fair knowledge and practice of SP among the studied HCWs while attitude was good.Rwanda J Med Health Sci 2021;4(3):366-378
Uptake of Cervical Cancer Screening and Associated Factors Among Women Attending Outpatient Services in Rwamagana Hospital, Rwanda
Authors: Ndateba Innocent , Kabatsinda Athanasie , Ndabarora Eléazar
Published: January 2022

BackgroundCervical cancer is a global public health threat for women. Rwanda Ministry of Health recommends screening as preventive strategy. However, the screening remains low in Rwanda.ObjectiveTo determine the uptake level of cervical cancer screening and associated factors among Rwandan women.MethodsA quantitative analytical cross-sectional study design was used. We recruited 178 participants using convenience sampling from an estimated 320 women who attended outpatient department in the previous month. The sample size was calculated using the Yamane’s formula. We used chi-square test, t-test and multiple logistic regression analysis to analyse data.ResultsA total of 178 (100%) participants completed the survey. Forty-one (23%) participants had undertaken cervical cancer screening. Knowledge (OR: 1.26,95% CI:1.069-1.485, p=.006) and income were predictors of cervical cancer screening uptake. Participants earning RWF ≥ 63,751 were more likely to uptake cervical cancer screening (OR:11.141, 95% CI:3.136-39.571, p< .001) compared to those earning less than RWF 25,500 monthly.ConclusionCervical cancer screening uptake among study population was low. Participants with more knowledge and high-income were more likely to uptake cervical cancer screening. Improving women’s knowledge and socioeconomic situation would improve the uptake of cervical cancer screening.Rwanda J Med Health Sci 2021;4(3):387-397
Long non-coding RNA KCNQ1 opposite transcript 1 (KCNQ1OT1) regulates cell proliferation and invasion via targeting miR-124-3p in gastric carcinoma
Authors: Ye Xinying , Liu Hongfu , Zeng Zhen
Published: January 2022

No Abstract.