bluuebunny/crossref_metadata_2025_split huggingface dataset:
TOOLS WITH SECONDARY TREATMENT OF THE LATE PALEOLITHIC SITE NEAR THE KAMYANKA VILLAGE
Authors: Snizhko I. A. 
Published: April 2021

The tools with secondary treatment from collection of the Late Paleolithic site near the Kamyanka village of Izum district in Kharkiv region are published in the paper. The collection of 8356 flint artifacts comes from the excavated area of 225 m2. The group of the tools with secondary treatment is not large — it consists of 88 items (1.05 %), typical for sites located near flint raw material outputs, where primary treatment took place directly in the dwelling area. From 27 burins 16 are straight burins, 5 are angle burins, 5 are truncation burins, a flat-faceted burin, a many-faceted burin and a double burin. As a preform, the flakes, blades, massive flakes and residual cores were used. There are 12 end-scrapers and scrapers; end-scrapers on flakes and blades prevail. The tools with notches are represented by 9 exemplars. Working elements of the piercing tools (4 exemplars) are formed by several splits on the flakes; in one case the tool is combined with middle burin. 11 flakes and blades have retouched areas. Microblades with truncated edge are represented by 16 exemplars. Notched backed points (whole one and 2 fragments) have no analogs in collections of the sites of allied territories. A high trapeze on a wrong-shape blade, a massive blade with an angle unit pointed out by retouch, a chisel-like item, a disk-shaped tool with retouched area are represented in one exemplar for now.
Generally the tools set is typical for Epigravettian sites, though the presence of notched backed points in it raises a range of questions which can be answered on during the further research.
THE DONETSK NEOLITHIC CULTURE SITE OF BONDARIKHА II
Authors: Manko V. O. , Telizhenko S. A. 
Published: April 2021

The Neolithic site Bondarikha ІІ was explored 70 years ago by D. Ya. Telegin. The materials of the site were not processed utilizing modern methods. The authors of the paper re-examined and analyzed the site’s materials using current methodologies.
The Bondarikha II site is set along a natural boundary on what is now the south-eastern outskirts of the modern city of Izium, Kharkiv region. The location of the site is a section of an over-flooded terrace that stretches along the left bank of the River Siversky Donets, and a section of an older river bed named the Willow Pit. In the north, sections of the terrace were crossed by an unnamed stream, and its southern boundary defined by floodplains. The lowlands nearest the terrace are primarily comprised of wetlands.
It is quite clear that the Willow Pit was once an active river and seasonally may have transformed into a lake during times of flooding. The site is located approximately 7 m above the current floodplain. The general site position is typical for the Neolithic sites of Donetsk Culture, with the vast majority of which are located on terraces above the floodplain lakes of Siversky Donets, with the habitational remains occupying the highest areas of terraces, or the periphery / edges of such terraces.
The interpretation of Bondarikha material culture was quite simple. The presence of pencil-like blade cores, oblique truncated points of the Abuzova Balka and Donetsk types, a series of blades displaying abrupt retouch on edges, along with bilateral burins, scrapers on flakes, and ovate axes are attestation that the assemblage and complex are connected with the advanced stages of Donetsk Culture.
The estimation of the site’s age is possible only by the principles of relative chronology. The Mariupolian origin of the trapeze projectiles allows us to establish the earliest age range of the complex within the beginning of the VI millennium BC. However, the utilization of trapeze projectiles with flat dorsal retouch that spread in the basin of Siversky Donets in the third quarter of VI millennium BC is not present. Accordingly, we can safely place the age of the site within the first half of VI millennium BC.
REVISITING THE LATE BRONZE AGE STAROSILLIA DEPOSIT FROM THE CHERCASSY REGION
Authors: Kushtan D. P. 
Published: April 2021

Thirty eight years ago the set of bronze tools found near the Starosillia village in Gorodyshche district of Cherkasy region has been published. This Late Bronze Age deposit remains one of the most known in the region. Three «celts», sleeve chisel and cast bracelet were preserved till the present time (fig. 1). These finds are kept in the Cherkasy Museum of local history.
Starosillia deposit is important in terms of identification of main intercultural connections and contacts in the late 2nd mil. BC. The evidence, obtained over the last several dozen years, makes possible the new attribution of finds, their typology, area of spread and dating. Besides this, new publication of Starosillia deposit with drawing and photos of a high quality (it should be noted that the article of D. Telegin is lacking the drawing of one «celt») is required. This is why we need to turn back to the deposit.
Two «celts» belong (fig. 3, 4) to the Dichevo type (Oinacu variant) according to V. Dergachev. Their origin is linked to Lower Danube center, from where these tools were spread in the North Pontic region, the area of Noua and Sabatynivka (later — early Bilozerka) cultures. Double-eyelet «celt» (fig. 2) belongs to Kardashynka type according to V. Dergachev. Such tools were used in late Sabatynivka and early Bilozerka time. In case of the analyzed region, such tools are referred to populations of Bilozerka culture, while the related molds were mainly found in the Lower Dnieper region. This is also the case of sleeve chisels (fig. 5) which are being similar to the find from Starosillia. Cast bracelet (fig. 6) from the deposit is typical for Sabatynivka and Bilozerka cultures, from which such bracelets could spread to the area of Bilogrudivka culture. Thus, the deposition of Starosillia deposit may be dated to the early Bilozerka time (HaA1), 12th century BC, when the Middle Dnieper region was inhabited by populations of Bilogrudivka culture.
Hepatitis E: update and perspectives
Authors: GUȚU Veaceslav 
Published: April 2021

Introduction. There are approximately 20 million cases of HVE annually worldwide, leading to approximately 3.3 million symptomatic cases of acute hepatitis E. The WHO estimates that HEV caused approximately 44,000 deaths in 2015 accounting for 3.3% of the mortality rate due to viral hepatitis.
Material and methods. The study of 75 bibliographic sources was carried out. The scientific platforms EMBASE, PubMed, HINARI, data from the national libraries as well as international relevant reference data were thoroughly examined.
Results. The present relevant study has highlighted important aspects of hepatitis E virus infection. Along with the improved living conditions and water quality standards, the latter being a disease-causing factor in the transmission of HEV, both the developed and developing countries are facing HEV, particularly in high-risk population groups, including people who are employed in the pork-processing industry and beneficiaries of blood transfusions.
Conclusions. The countries' capacity to detect and control this infection is limited since it has not been included within the surveillance policies and programs yet. Risk factors associated with the epidemic process should be elucidated to provide and develop appropriate evidence-based measures to optimize the surveillance and control system in order to reduce the risk of contracting HEV and maintain favorable conditions for epidemiological safety.
Radiation Belt Response to Fast Reverse Shock at Geosynchronous Orbit
Authors: Bhaskar Ankush , Sibeck David , Kanekal Shrikanth G. , Singer Howard J. , Reeves Geoffrey , Oliveira Denny M. , Kang Suk-Bin , Komar Colin 
Published: April 2021

Abstract
Fast reverse shocks (FRSs) cause the magnetosphere to expand, by contrast to the well-known compressions caused by the impact of fast forward shocks (FFS). Usually, FFSs are more geoeffective than FRSs, and consequently the inner magnetosphere dynamic responses to both shock types can be quite different. In this study, we investigate for the first time the radiation belt response to an FRS impact using multi-satellite observations and numerical simulations. Spacecraft on the dayside observed decreases in magnetic field strength and energetic (∼40–475 keV) particle fluxes. Timing analysis shows that the magnetic field signature propagated from the dayside to the nightside magnetosphere. Particles with different energies vary simultaneously at each spacecraft, implying a non-dispersive particle response to the shock. Spacecraft located at lower L-shells did not record any significant signatures. The observations indicate a local time dependence of the response associated with the shock inclination, with the clearest signatures being observed in the dusk–midnight sector. Simulations underestimate the amplitude of the magnetic field variations observed on the nightside. The observed decreases in the electron intensities result from a combination of radial gradient and adiabatic effects. The radial gradients in the spectral index appear to be the dominant contributor to the observed variations of electrons seen on the dayside (near noon and dusk) and on the nightside (near midnight). This study shows that even an FRS can affect the radiation belts significantly and provides an opportunity to understand their dynamic response to a sudden expansion of the magnetosphere.
Gravitoviscous Protoplanetary Disks with a Dust Component. V. The Dynamic Model for Freeze-out and Sublimation of Volatiles
Authors: Molyarova Tamara , Vorobyov Eduard I. , Akimkin Vitaly , Skliarevskii Aleksandr , Wiebe Dmitri , Güdel Manuel 
Published: April 2021

Abstract
The snowlines of various volatile species in protoplanetary disks are associated with abrupt changes in gas composition and dust physical properties. Volatiles may affect dust growth, as they cover grains with icy mantles that can change the fragmentation velocity of the grains. In turn, dust coagulation, fragmentation, and drift through the gas disk can contribute to the redistribution of volatiles between the ice and gas phases. Here we present the hydrodynamic model FEOSAD for protoplanetary disks with two dust populations and volatile dynamics. We compute the spatial distributions of major volatile molecules (H2O, CO2, CH4, and CO) in the gas, on small and grown dust, and analyze the composition of icy mantles over the initial 0.5 Myr of disk evolution. We show that most of the ice arrives to the surface of the grown dust through coagulation with small grains. Spiral structures and dust rings forming in the disk, as well as photodissociation in the outer regions, lead to the formation of complex snowline shapes and multiple snowlines for each volatile species. During the considered disk evolution, the snowlines shift closer to the star, with their final position being a factor of 4–5 smaller than that at the disk formation epoch. We demonstrate that volatiles tend to collect in the vicinity of their snowlines, both in the ice and gas phases, leading to the formation of thick icy mantles potentially important for dust dynamics. The dust size is affected by a lower fragmentation velocity of bare grains in the model with a higher turbulent viscosity.
Continuous Jets and Backflow Models for the Formation of W50/SS 433 in Magnetohydrodynamics Simulations
Authors: Ohmura T. , Ono K. , Sakemi H. , Tashima Y. , Omae R. , Machida M. 
Published: April 2021

Abstract
The formation mechanism of the W50/SS 433 complex has long been a mystery. We propose a new scenario in which the SS 433 jets themselves form the W50/SS 433 system. We carry out magnetohydrodynamics simulations of the propagation of two side jets using the public code CANS+. As found in previous jet studies, when the propagating jet is lighter than the surrounding medium, the shocked plasma flows back from the jet tip to the core. We find that the morphology of light jets is spheroidal at early times; afterward, the shell and wings are developed by the broadening spherical cocoon. The morphology depends strongly on the density ratio of the injected jet to the surrounding medium. Meanwhile, the ratio of the lengths of the two side jets depends only on the density profile of the surrounding medium. We also find that most of the jet kinetic energy is dissipated at the oblique shock formed by the interaction between the backflow and beam flow, rather than at the jet terminal shock. The position of the oblique shock is spatially consistent with the X-ray and TeV gamma-ray hotspots of W50.
Pristine PSP/WISPR Observations of the Circumsolar Dust Ring near Venus's Orbit
Authors: Stenborg Guillermo , Gallagher Brendan , Howard Russell A. , Hess Phillip , Raouafi Nour Eddine 
Published: April 2021

Abstract
The Parker Solar Probe mission (PSP) has completed seven orbits around the Sun. The Wide-field Imager for Solar Probe (WISPR) on PSP consists of two visible light heliospheric imagers, which together image the interplanetary medium between 13.°5 and 108° elongation. The PSP/WISPR nominal science observing window occurs during the solar encounters, which take place when the spacecraft (S/C) is within 0.25 au from the Sun. During Orbit 3, an extended science campaign took place while PSP transited between 0.5 and 0.25 au (during both inbound and outbound orbit segments). PSP mission operations implemented a variety of 180° S/C rolls about the S/C-Sun pointing axis during the extended science window. The vantage of the PSP location, combined with the different S/C roll orientations, allowed us to unveil a circumsolar dust density enhancement associated with Venus’s orbit. Specifically, we observed an excess brightness band of about 1% at its center over the brightness of the background zodiacal light in all PSP/WISPR images obtained during the extended campaign. We explain this brightness band as due to an increase in the density of the circumsolar dust orbiting the Sun close to the Venusian orbit. The projected latitudinal extent of the ring is estimated at about 0.043 au ± 0.004 au, exhibiting an average density enhancement of the order of 10%. Here, we report and characterize the first comprehensive, pristine observations of the plane-of-sky projection of the dust ring in almost its full 360° longitudinal extension.
Experimental Study on CH+ Formation from Doubly Charged Carbon and Molecular Hydrogen
Authors: Plašil Radek , Rednyk Serhiy , Kovalenko Artem , Tran Thuy Dung , Roučka Štěpán , Dohnal Petr , Novotný Oldřich , Glosík Juraj 
Published: April 2021

Abstract
We studied the reaction of doubly charged carbon C2+ (C iii) with molecular hydrogen, a possible source of the high, unexplained abundances of interstellar CH+. The experiment was carried out using the cryogenic linear 22-pole radio frequency ion trap. The measured reaction rate coefficient amounts to (1.5 ± 0.2) × 10−10 cm3 s−1, nearly independently of the covered temperature range from 15 to 300 K. In the product distribution study, the C+ ion was identified as the dominant product of the reaction. For the CH+ production, we determine an upper limit for the reaction rate coefficient at 2 × 10−12 cm3 s−1.
When the Peas Jump around the Pod: How Stellar Clustering Affects the Observed Correlations between Planet Properties in Multiplanet Systems
Authors: Chevance Mélanie , Diederik Kruijssen J. M. , Longmore Steven N. 
Published: April 2021

Abstract
Recent studies have shown that the radii and masses of adjacent planets within a planetary system are correlated. It is unknown how this “peas-in-a-pod” phenomenon originates, whether it is in place at birth or requires evolution, and whether it (initially) applies only to neighboring planets or to all planets within a system. Here we address these questions by making use of the recent discovery that planetary system architectures strongly depend on ambient stellar clustering. Based on Gaia's second data release, we divide the sample of planetary systems hosting multiple planets into those residing in stellar position–velocity phase space overdensities and the field, representing samples with elevated and low degrees of external perturbation, respectively. We demonstrate that the peas-in-a-pod phenomenon manifests itself in both samples, suggesting that the uniformity of planetary properties within a system is not restricted to direct neighbors and likely already exists at birth. The radius uniformity is significantly elevated in overdensities, suggesting that it can be enhanced by evolutionary effects that either have a similar impact on the entire planetary system or favor the retention of similar planets. The mass uniformity may exhibit a similar, but weaker dependence. Finally, we find ordering in both samples, with the planet radius and mass increasing outwards. Despite its prevalence, the ordering is somewhat weaker in overdensities, suggesting that it may be disrupted by external perturbations arising from stellar clustering. We conclude that a comprehensive understanding of the peas-in-a-pod phenomenon requires linking planet formation and evolution to the large-scale stellar and galactic environment.
Minidisk Dynamics in Accreting, Spinning Black Hole Binaries: Simulations in Full General Relativity
Authors: Paschalidis Vasileios , Bright Jane , Ruiz Milton , Gold Roman 
Published: April 2021

Abstract
We perform magnetohydrodynamic simulations of accreting, equal-mass binary black holes in full general relativity focusing on the impact of black hole spin on the dynamical formation and evolution of minidisks. We find that during the late inspiral the sizes of minidisks are primarily determined by the interplay between the tidal field and the effective innermost stable orbit around each black hole. Our calculations support that a minidisk forms when the Hill sphere around each black hole is significantly larger than the black hole’s effective innermost stable orbit. As the binary inspirals, the radius of the Hill sphere decreases, and minidisks consequently shrink in size. As a result, electromagnetic signatures associated with minidisks may be expected to gradually disappear prior to merger when there are no more stable orbits within the Hill sphere. In particular, a gradual disappearance of a hard electromagnetic component in the spectrum of such systems could provide a characteristic signature of merging black hole binaries. For a binary of given total mass, the timescale to minidisk “evaporation” should therefore depend on the black hole spins and the mass ratio. We also demonstrate that accreting binary black holes with spin have a higher efficiency for converting accretion power to jet luminosity. These results could provide new ways to estimate black hole spins in the future.
A Highly Collimated Flow from the High-mass Protostar ISOSS J23053+5953 SMM2
Authors: Rodríguez Tatiana M. , Hofner Peter , Araya Esteban , Zhang Qizhou , Linz Hendrik , Cesaroni Riccardo , Kurtz Stan , Gomez Laura , Carrasco-González Carlos , Rosero Viviana 
Published: April 2021

Abstract
We present Very Large Array cm continuum observations, as well as 1.3 mm continuum and CO(2–1) observations taken with the Submillimeter Array toward the high-mass protostellar candidate ISOSS J23053+5953 SMM2. Compact cm continuum emission was detected near the center of the SMM2 dust core, and the 1.3 mm thermal dust emission indicates a core mass of 46  M
⊙. The CO(2–1) observation revealed a large, massive molecular flow centered on the SMM2 core. This fast outflow (>50 km s−1) appears highly collimated, with a broader, lower-velocity component. The large values for outflow mass (45 M
⊙), and energetics derived are consistent with those of flows driven by high-mass YSOs. The dynamical timescale of the flow is between 1.5−7.2 × 104 yr. Our data confirm previous findings that SMM2 is an emerging high-mass protostar in a very early phase of evolution, with an ionized jet, and a fast, highly collimated, and massive outflow.
Practical Effects of Integrating Temperature with Strang Split Reactions
Authors: Zingale M. , Katz M. P. , Willcox D. E. , Harpole A. 
Published: April 2021

Abstract
Many astrophysical environments involve convective or explosive flows driven by thermonuclear reactions (Type Ia supernovae, classical novae, X-ray bursts, stellar evolution). Simulation codes need to accurately capture the interactions between reactions and hydrodynamics to produce realistic models of these events. For astrophysical reacting flows, operator splitting is commonly used to couple hydrodynamics and reactions. Each process operates independent of one another, but by staggering the updates in a symmetric fashion (via Strang splitting) second order accuracy in time can be achieved. However, approximations are often made to the reacting system, including the choice of whether or not to integrate temperature with the species. Here we demonstrate through a simple convergence test that integrating an energy equation together with reactions achieves the best convergence when modeling reactive flows with Strang splitting. Additionally, second order convergence cannot be achieved without integrating an energy or temperature equation.
Formation of the Lunar Dust Ejecta Cloud
Authors: Bernardoni Edwin , Horányi Mihály , Szalay Jamey 
Published: April 2021

Abstract
The Lunar Dust Experiment (LDEX) on board the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission orbited the Moon from 2014 September to 2015 April and observed a dynamic, permanently present dust cloud produced by continual meteoroid bombardment. For the latitudes observed by LDEX, the sporadic background contribution to the impacting dust flux is dominated by helion (HE), apex (AP), and antihelion (AH) sources oscillating with lunar phase. Using improved impact ejecta distributions, a three-dimensional model was implemented to estimate the inner and outer ejecta cone angles from LDEX plume measurements. Expanding upon this single-plume model and the derived ejecta cone angles, we implemented a global lunar model fitted to LDEX measurements of the sporadic background to constrain the product of meteoroid impactor fluxes and ejecta mass yield per source. We use the observed asymmetry between sunward and antisunward impactor fluxes to discuss the possible contributions of β-meteoroids, in addition to the HE and AH sporadic meteoroid sources. We find that if β-meteoroids are responsible for the day/night asymmetry, they must have an impact ejecta yield of at least 103.
Entre le transnational et le local Transversalités et spécificités du partenariat éducatif à Genève
Authors: Rufin Diane 
Published: April 2021

À partir du cas genevois, cet article vise à étudier la coloration singulière du partenariat éducatif qui prend place entre des transversalités transnationales et des spécificités locales. Dans un premier temps, la présentation du contexte, de la genèse et de l’évolution du partenariat éducatif montre que des éléments politiques, culturels ou historiques teintent son développement. Dans un second temps, le partenariat éducatif est décliné à trois niveaux de l’action éducative pour l’enseignement primaire (politico-institutionnel, établissements, enseignants). Le cas genevois apparaît au final singulier : la collaboration entre l’école et les services médico-pédagogiques y est ancienne, tandis que l’injonction récente au partenariat déstabilise les contours professionnels. Une constante demeure toutefois, autour d’une conception psycho-médicale des difficultés de l’élève et de leurs modes de résolution, interrogeant plus fondamentalement la spécificité de l’acte d’enseigner.