bluuebunny/crossref_metadata_2025 huggingface dataset:
Semiconducting SiGeSn high-entropy alloy: A density functional theory study
Authors: Wang Duo , Liu Lei , Huang Wenjiang , Zhuang Houlong L.
Published: December 2019

High-entropy alloys (HEAs), which have been intensely studied due to their excellent mechanical properties, generally refer to alloys with multiple equimolar or nearly equimolar elements. According to this definition, Si-Ge-Sn alloys with equal or comparable concentrations of the three group IV elements belong to the category of HEAs. As a result, the equimolar elements of Si-Ge-Sn alloys likely cause their atomic structures to exhibit the same core effects of metallic HEAs such as lattice distortion. Here, we apply density functional theory (DFT) calculations to show that the SiGeSn HEA indeed exhibits a large local distortion effect. Unlike metallic HEAs, our Monte Carlo and DFT calculations show that the SiGeSn HEA exhibits no chemical short-range order due to the similar electronegativity of the constituent elements, thereby increasing the configurational entropy of the SiGeSn HEA. Hybrid density functional calculations show that the SiGeSn HEA remains semiconducting with a bandgap of 0.38 eV, promising for economical and compatible midinfrared optoelectronic applications. We then study the energetics of neutral single Si, Ge, and Sn vacancies and (expectedly) find wide distributions of vacancy formation energies, similar to those found in metallic HEAs. However, we also find anomalously small lower bounds (e.g., 0.04 eV for a Si vacancy) in the energy distributions, which arise from the bond reformation near the vacancy. Such small vacancy formation energies and their associated bond reformations retain the semiconducting behavior of the SiGeSn HEA, which may be a signature feature of a semiconducting HEA that differentiates from metallic HEAs.
Comparative proteomic analysis of latex from Euphorbia kansui laticifers at different development stages with and without UV-B treatment via iTRAQ-coupled two-dimensional liquid chromatography–MS/MS
Authors: Zhao Xueyan , Zhang Yue , Wang Meng , Fang Xiaoai , Cai Xia
Published: December 2019

Euphorbia kansui Liou, an endemic species in China, is well-known in traditional Chinese medicine. All parts of E. kansui contain white latex, which is the protoplasm constituent of specialised cells known as laticifers. The latex contains many proteins with various biological functions. In the present study, isobaric tagging for relative and absolute quantitation (iTRAQ) and MS technology combined with western blot and quantitative real-time PCR analysis were used to identify latex proteins and analyse differentially accumulated proteins in laticifers at different development stages, with and without UV-B treatment according to the E. kansui transcriptome database and the NCBI Euphorbiaceae RefSeq protein database. A total of 322 latex proteins were successfully identified. Proteasome subunits, ubiquitinated proteins, vacuolar ATP synthase (V-ATPase) and lysosomal enzymes decreased, keeping the content at a higher level in laticifers in the early development stage. These results suggest that the ubiquitin–proteasome pathway and the lysosome autophagy pathway were involved in the partial degradation of laticifer cytoplasm. In addition, terpenoid biosynthesis-related proteins, 14–3–3 protein, V-ATPase and lysosomal enzymes increased under UV-B treatment, which showed that partial cytoplasmic degradation is positively correlated with secondary metabolite synthesis in the development of E. kansui laticifers. Besides, UV-B radiation can increase plant resistance by promoting laticifer development in E. kansui. This information provides a basis for further exploration of E. kansui laticifer development, and terpenoid synthesis and regulation.
Disappearance of the last tropical glaciers in the Western Pacific Warm Pool (Papua, Indonesia) appears imminent
Authors: Permana Donaldi S. , Thompson Lonnie G. , Mosley-Thompson Ellen , Davis Mary E. , Lin Ping-Nan , Nicolas Julien P. , Bolzan John F. , Bird Broxton W. , Mikhalenko Vladimir N. , Gabrielli Paolo , Zagorodnov Victor , Mountain Keith R. , Schotterer Ulrich , Hanggoro Wido , Habibie Muhammad N. , Kaize Yohanes , Gunawan Dodo , Setyadi Gesang , Susanto Raden D. , Fernández Alfonso , Mark Bryan G.
Published: December 2019

The glaciers near Puncak Jaya in Papua, Indonesia, the highest peak between the Himalayas and the Andes, are the last remaining tropical glaciers in the West Pacific Warm Pool (WPWP). Here, we report the recent, rapid retreat of the glaciers near Puncak Jaya by quantifying the loss of ice coverage and reduction of ice thickness over the last 8 y. Photographs and measurements of a 30-m accumulation stake anchored to bedrock on the summit of one of these glaciers document a rapid pace in the loss of ice cover and a ∼5.4-fold increase in the thinning rate, which was augmented by the strong 2015–2016 El Niño. At the current rate of ice loss, these glaciers will likely disappear within the next decade. To further understand the mechanisms driving the observed retreat of these glaciers, 2 ∼32-m-long ice cores to bedrock recovered in mid-2010 are used to reconstruct the tropical Pacific climate variability over approximately the past half-century on a quasi-interannual timescale. The ice core oxygen isotopic ratios show a significant positive linear trend since 1964 CE (0.018 ± 0.008‰ per year;P< 0.03) and also suggest that the glaciers’ retreat is augmented by El Niño–Southern Oscillation processes, such as convection and warming of the atmosphere and sea surface. These Papua glaciers provide the only tropical records of ice core-derived climate variability for the WPWP.
Ventral hippocampus interacts with prelimbic cortex during inhibition of threat response via learned safety in both mice and humans
Authors: Meyer Heidi C. , Odriozola Paola , Cohodes Emily M. , Mandell Jeffrey D. , Li Anfei , Yang Ruirong , Hall Baila S. , Haberman Jason T. , Zacharek Sadie J. , Liston Conor , Lee Francis S. , Gee Dylan G.
Published: December 2019

Heightened fear and inefficient safety learning are key features of fear and anxiety disorders. Evidence-based interventions for anxiety disorders, such as cognitive behavioral therapy, primarily rely on mechanisms of fear extinction. However, up to 50% of clinically anxious individuals do not respond to current evidence-based treatment, suggesting a critical need for new interventions based on alternative neurobiological pathways. Using parallel human and rodent conditioned inhibition paradigms alongside brain imaging methodologies, we investigated neural activity patterns in the ventral hippocampus in response to stimuli predictive of threat or safety and compound cues to test inhibition via safety in the presence of threat. Distinct hippocampal responses to threat, safety, and compound cues suggest that the ventral hippocampus is involved in conditioned inhibition in both mice and humans. Moreover, unique response patterns within target-differentiated subpopulations of ventral hippocampal neurons identify a circuit by which fear may be inhibited via safety. Specifically, ventral hippocampal neurons projecting to the prelimbic cortex, but not to the infralimbic cortex or basolateral amygdala, were more active to safety and compound cues than threat cues, and activity correlated with freezing behavior in rodents. A corresponding distinction was observed in humans: hippocampal–dorsal anterior cingulate cortex functional connectivity—but not hippocampal–anterior ventromedial prefrontal cortex or hippocampal–basolateral amygdala connectivity—differentiated between threat, safety, and compound conditions. These findings highlight the potential to enhance treatment for anxiety disorders by targeting an alternative neural mechanism through safety signal learning.
Combining conservation and species-specific differences to determine how human telomerase binds telomeres
Authors: Tesmer Valerie M. , Smith Eric M. , Danciu Oana , Padmanaban Shilpa , Nandakumar Jayakrishnan
Published: December 2019

Significance

The telomerase enzyme is recruited to chromosome ends by telomeric protein TPP1 to replenish DNA that is lost during DNA replication. Although telomerase is not expressed in most of our cells, its presence is key to the continued division of stem cells and is exploited by a majority of cancers for their growth. Here, we used chimeras of mouse and human telomerase to define the regions necessary for interacting with TPP1. We then employed a multilayered, site-directed mutagenesis screen to reveal finer details of the surface that human telomerase uses to bind TPP1. Combining our data with the previously mapped interaction surface on TPP1, we present a functionally validated structural model for the human telomerase–TPP1 interaction.
Viral neutralization by antibody-imposed physical disruption
Authors: Zheng Qingbing , Jiang Jie , He Maozhou , Zheng Zizheng , Yu Hai , Li Tingting , Xue Wenhui , Tang Zimin , Ying Dong , Li Zekai , Song Shuo , Liu Xinlin , Wang Kaihang , Zhang Zhiqing , Wang Daning , Wang Yingbin , Yan Xiaodong , Zhao Qinjian , Zhang Jun , Gu Ying , Li Shaowei , Xia Ningshao
Published: December 2019

In adaptive immunity, organisms produce neutralizing antibodies (nAbs) to eliminate invading pathogens. Here, we explored whether viral neutralization could be attained through the physical disruption of a virus upon nAb binding. We report the neutralization mechanism of a potent nAb 8C11 against the hepatitis E virus (HEV), a nonenveloped positive-sense single-stranded RNA virus associated with abundant acute hepatitis. The 8C11 binding flanks the protrusion spike of the HEV viruslike particles (VLPs) and leads to tremendous physical collision between the antibody and the capsid, dissociating the VLPs into homodimer species within 2 h. Cryo-electron microscopy reconstruction of the dissociation intermediates at an earlier (15-min) stage revealed smeared protrusion spikes and a loss of icosahedral symmetry with the capsid core remaining unchanged. This structural disruption leads to the presence of only a few native HEV virions in the ultracentrifugation pellet and exposes the viral genome. Conceptually, we propose a strategy to raise collision-inducing nAbs against single spike moieties that feature in the context of the entire pathogen at positions where the neighboring space cannot afford to accommodate an antibody. This rationale may facilitate unique vaccine development and antimicrobial antibody design.
Politeness, gender and the social balance of the Homeric household
Authors: Mari Francesco
Published: December 2019

This paper focusses on the role of women within the Homeric household (οἶκος, “oikos”) as related to politeness. The social balance of the household has its fulcrum in the relation between the householder and his wife, and the latter has a crucial role in preserving the face of her husband and hence his authority in the oikos. In practice, to preserve his public image within the oikos, householders delegate a core part of their authority to their wives, and in exchange of this wife-characters such as Penelope or the goddess Hera are keen always to stage the subaltern role, which women have in the Homeric society. The paper compares specific examples of similar politeness strategies to the behaviour of Helen in Book 6 of theIliad(321–356). Helen enacts a reverse politeness strategy aiming to make her husband Paris’s face collapse in front of Hector. By combining Erving Goffman’s concepts of “face” and “social situation” and the Homeric values of τιμή (“timē”) and αἰδώς (“aidōs”) into a framework for studying politeness in the epics, it becomes possible to shed light on the real power balance that – underneath the veil of politeness – characterises the relationship between the householder and his wife in the Homeric oikos.
The Northumbrian Old English glosses
Authors: van Gelderen Elly
Published: December 2019

The articles in this volume contribute to our understanding of Northumbrian Old English of the 10th century, of the nature of external influence, and of the authorship of the glosses. This introduction provides a background to these three areas. Most of the introduction and contributions examine the Lindisfarne Glosses with some discussion of the Rushworth and Durham Glosses.Section 2shows that the Lindisfarne glossator often adds a (first and second person) pronoun where the Latin has none but allows third person null subjects. Therefore, although the Latin original has obvious influence, Old English grammar comes through.Section 3reviews the loss of third person-thverbal inflection in favor of-s, especially in Matthew. This reduction may be relevant to the role of external (Scandinavian and British Celtic) influence and is also interesting when the language of the Lindisfarne and Durham Glosses is compared. InSection 4, the use of overt pronouns, relatives, and demonstratives shows an early use ofth-pronouns, casting doubt on a Norse origin ofthey.Section 5looks at negation mainly from a northern versus southern perspective andSection 6sums up.Section 7previews the other contributions and their major themes, namely possible external (Latin, Norse, or British Celtic) influence, the linguistic differences among glossators, the spacing of ‘prefixes’ as evidence for grammaticalization, and the role of doublets.
Verbal morphology in the Old English gloss to the Durham Collectar
Authors: Fernández Cuesta Julia , Langmuir Christopher
Published: December 2019

This article examines the verbal morphology of the Old English interlinear gloss to the Durham Collectar, attributed by almost universal consensus to Aldred of Chester-le-Street, whose earlier gloss to the Lindisfarne Gospels has recently been the object of scholarly attention (Cole 2014;Fernández Cuesta & Pons-Sanz 2016,Gameson et al. 2017). This article analyses -s/-thvariation in the present indicative and imperative forms in relation to their syntactic context, in particular subject type and subject-verb adjacency, in order to assess whether the Northern Subject Rule detected byCole (2014)in Lindisfarne was also operative in Aldred’s later gloss. By means of a quantitative analysis, we find that the first constraint does not significantly affect -s/-ðvariation in the gloss and that there is insufficient context for the second. Additionally, it is argued that adjacency is a problematic variable in this text-type. We also demonstrate that there is a higher percentage of second person singular -stand -ðin the Collectar than in Lindisfarne and discuss the possible influence of standard West Saxon on the later gloss.
The subjunctive in the Lindisfarne gloss
Authors: Wood Johanna
Published: December 2019

The use of the subjunctive mood in the Old English gloss to the Lindisfarne Gospels is
investigated. All the examples of the Latin third person singular imperfect subjunctive, esset, are examined.
There are three aims: to contribute to understanding the use of the subjunctive in the gloss of the Lindisfarne Gospels; to add to
the authorship debate; to explore the question of how much Latin influences the glosses. Although, generally, indicative mood is
expected in Old English adverbial temporal clauses, this clause type is often found in the subjunctive. The tendency is strongest
in the Gospel of Luke. A few doublets of subjunctive and indicative occur, but only in the Gospels of Luke and John.
Verbal prefixes in Old Northumbrian
Authors: Kruger William W.
Published: December 2019

In late Old English dialects, adverbial elements are frequently morphologically ambiguous (independent words,
clitics, verbal prefixes, etc.), and an important facet of the proper treatment of these items is the quality of source-data in
different texts. This paper examines the usage of three adverbial/prepositional elements in the Northumbrian Lindisfarne Glosses:
eft ‘again, after’, ymb ‘around’, and ofer ‘over’. Skeat (1871–87), whose transcription of the original manuscript is the primary reference for research on
the Glosses, frequently transcribes these items as prefixes, alongside other OE prefixes like ge-,
a-, for-, and be-. However, Skeat also deviates from this pattern in many
cases, leaving their proper analysis uncertain. Nevertheless, various works (e.g., Cook
1894; Bosworth 2011), have indeed taken these items to be prefixes. I follow
Fernández-Cuesta (2016) in revisiting the original Lindisfarne manuscript to
determine the correct treatment of these items, concluding that eft and ofer should not be
analyzed as prefixes in the manuscript, while ymb should have prefix status.
Reinforcing and toughening carbon fiber/epoxy composites with styrene–butadiene–styrene copolymer grafted carbon nanotubes
Authors: Yuan  , Chen  , Wang  , Li  , Wei  , Hong  , Chen  , Qiao  , Wang
Published: December 2019

SBS-g-MWNTs/carbon fiber/epoxy (SBS-g-MWNTs/CF/EP) three-phase composite laminates were fabricated to study the effect of styrene-butadiene-styrene triblock copolymer grafted multi-walled carbon nanotubes (SBS-g-MWNTs) on mechanical performance of carbon fiber-reinforced composite.
The chemical grafting of styrene-butadiene-styrene (SBS) on multi-walled carbon nanotubes (MWNTs) was characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), transmission electron microscopic (TEM) and thermogravimetric
analysis (TGA). The mechanical properties of SBS-g-MWNTs filled CF/EP composites were evaluated by tensile, flexural, impact and interfacial shear strength (ILSS) tests. Results showed that SBS-g-MWNTs was homogeneously dispersed in epoxy matrix and the existence of SBS-g-MWNTs effectively
strengthened the interfacial adhesion between carbon fiber and epoxy, leading to remarkable enhancement in impact strength by 90.2% and ILSS by 99.7% of the composites with as low as 0.50 wt.% SBS-g-MWNTs, along with other improved mechanical properties.
Drawing on disorder: How viruses use histone mimicry to their advantage
Authors: Tarakhovsky Alexander , Prinjha Rab K.
Published: December 2019

Humans carry trillions of viruses that thrive because of their ability to exploit the host. In this exploitation, viruses promote their own replication by suppressing the host antiviral response and by inducing changes in host biosynthetic processes, often with extremely small genomes of their own. In the review, we discuss the phenomenon of histone mimicry by viral proteins and how this mimicry allows the virus to dial in to the cell’s transcriptional processes and establish a cell state that promotes infection. We suggest that histone mimicry is part of a broader viral strategy to use intrinsic protein disorder as a means to overcome the size limitations of its own genome and to maximize its impact on host protein networks. In particular, we discuss how intrinsic protein disorder may enable viral proteins to interfere with phase-separated host protein condensates, including those that contribute to chromatin-mediated control of gene expression.
Flux vortex dynamics in type-II superconductors
Authors: Srpčič J , Moseley D A , Perez F , Huang K Y , Shi Y , Dennis A R , Ainslie M D , Campbell A M , Boll M , Cardwell D A , Durrell J H
Published: December 2019

The flux-pinning landscape in type-II superconductors determines the response of the flux line lattice to changing magnetic fields. Typically, the flux vortex behaviour is hysteretic and well described within the framework of the Bean critical-state model and its extensions. However, if the changing magnetic field does not move the flux vortices from their pinning sites, their response remains linear and reversible. The vortex displacement, then, is characterised by the Campbell penetration depth, which itself is related directly to the effective size of the pinning potential. Here, we present measurements of the Campbell penetration depth (and the effective size of the pinning potential) as a function of magnetic field in a single-grain bulk GdBa2Cu3O

7
−
δ

superconductor using a pick-up coil method. Hence, the hysteretic losses, which take into account the reversible vortex movement, are established.
Recent Studies of the Resonances at a Cell Tune of 0.25 Using the Ibex Paul Trap
Authors: Martin L. K. , Kelliher D. J. , Sheehy S. L.
Published: December 2019

We use the IBEX linear Paul trap to study the resonance at a cell tune of

1
4

with both equal and unequal transverse tunes, at a range on intensities. We compare this experimental result to simulation using the PIC code Warp. We find that the experimental result differs from the simulation, which may be explained by the ion loss in the IBEX experiment, which more closely replicates a real accelerator. Knowledge of the tune corresponding to greatest beam loss is important for the design of future high intensity machines.
The Esr Closed Orbit Calculation And Simulation
Authors: Dastan S. , Litvinov S. , Steck M. , Saffari R. , Rahighi J.
Published: December 2019

The commissioning of the Experimental Storage Ring (ESR) with a new control system based on the LSA (LHC System Architecture) has started recently. The aim with these updates were that the 25-year-old control system, which was based on outdated computers and operating system, was discontinued. In addition, the front-end components of the hardware were also 25 years old and couldn’t be serviced any more, they are modernized together with the control system. This new control system is under development and considers all aspects of the expected functionality to operate the GSI/FAIR accelerators and incorporates the present GSI controls infrastructure [1]. So, both the heavy ion synchrotron SIS-18 and the ESR operation from now on have to be performed with the new FAIR control system. In order to introduce an improved model to the control system change, new calculations and simulations for SIS and ESR are necessary. In this paper we summarize the results of closed orbit calculations for the ESR which are done with three different codes, namely: ELEGANT [2], MAD-X [3] and MIRKO [4]. Considering similar results between MAD-X and ELEGANT, we present ELEGANT results in the report. In fact, the simulation for the old control system had done with MIRKO which worked fine. For the new control system, we decided to use these three codes for numerical simulation, but using MIRKO values in ELEGANT did not agree well, therefore the ELEGANT input was checked and adapted for better agreement. It is not yet clear that the details of the large aperture ESR magnets are treated in the same way in the two codes and higher order field components affect the result of the orbit calculation. This might be the origin of the difference between ELEGANT and MIRKO results.
Energy Calibration of the ReA3 Accelerator by Time-of- Flight Technique1
Authors: Villari A C C , Crisp D B , Lapierre A , Nash S , Summers T , Zhao Q
Published: December 2019

We report on a simple method to perform an absolute calibration of the magnetic beam analyzer of the reaccelerator ReA3 at the National Superconducting Cyclotron Laboratory. The method is based on the time of flight between two beam stoppers 7.65 m apart. Based on two independent time-of-flight measurements at three different beam energies, the beam analyzer magnet is calibrated with an accuracy of 0.12 %, corresponding to a beam energy accuracy of 0.24 %.
Development of low inductance circuit for radially symmetric circuit
Authors: Takayanagi T , Ueno T , Horino K
Published: December 2019

The switch of the radially-symmetric circuit using semiconductors of SiC-MOSFET, which is one of the next-generation semiconductors, consists of a circuit in which many semiconductor switches are arrayed in parallel. Since all parallel circuits are equal in length, distortion due to timing jitter or impedance difference does not occur on principle in the merged output waveform. This circuit is useful for outputting an ultrashort pulse waveform. Therefore, we have developed a circuit board that achieves even lower inductance of the power transmission circuit by making a double ring structure equivalent to a coaxial shape. We compare the results of calculation, analysis and measurement, and the superiority of the developed coaxial-type is presented here.
Cleanroom installations for SRF cavities at the Helmholtz Institute Mainz
Authors: Kürzeder T , Aulenbacher K , Barth W , Burandt C , Conrad J , Dziuba F , Gettmann V , Heine R , Hug F , Lauber S , List J , Miski-Oglu M , Stengler T , Yaramyshev S
Published: December 2019

At the Helmholtz-Institut Mainz (HIM) a cleanroom has been equipped with new tools and installations for the planned treatment of different superconducting RF-cavities. Therefore, the cleanroom had to be shut down and some walls and part of the ceiling had to be dismantled. In its ISO-class 6 area a large ultrasonic and a conductance rinsing bath has been installed. A high pressure rinsing cabinet has been implemented between the ISO-class 6 and 4 cleanroom so that a cavity can be loaded and unloaded from both sides. For drying the ISO-class 4 cleanroom was equipped with a 160°C vacuum oven. Afterwards the cleanroom was sealed again and put back in operation. New cleanroom lift trolleys allow the handling of heavy objects (max. 200 kg). By a rail system in the cleanroom floor it is possible to move entire cold strings through the different clean room classes separated by a roll-up door. This paper reports on the reclassification of the cleanroom after it went back to operation and first experiences with its cleaning. Particle measurements of equipment in operation will be presented as well.
Thermodynamic properties of Coulomb crystals with isotopic impurities
Authors: Kozhberov Andrew
Published: December 2019

This work is devoted to a description of Coulomb crystals with isotopic impurities which are expected to be formed in degenerate stars interiors. We consider the case when the mass of impurities M′
is slightly different from the mass of ‘basic’ ions M while fraction of impurities can be arbitrary. It is shown that the heat capacity perturbation theory of disordered crystals is in a good agreement with the linear mixing theory and with the exact calculations for binary crystals.
Diagnostics of Accelerated Electrons Anisotropy from Solar Hard X-rays
Authors: Oparin I D , Charikov Yu E , Ovchinnikova E P , Shabalin A N
Published: December 2019

In most acceleration models only the energy distribution of the particles can be obtained, while the angular part of the distribution remains still unclear. The article represents the possibility of detecting the electron distribution anisotropy. The Hard X-ray spectrums, polarization degree and directivity for different models of anisotropy are calculated. The calculations claimed the possibility of determining the longitudinal-transverse anisotropy of electrons.
B1951+32 pulsar bow shock proper motion measurements based on Gemini North 8-m telescope and HST optical observations
Authors: Abramkin V J , Shibanov Yu A , Zyuzin D A , Pavlov G G
Published: December 2019

Using deep optical images of the core of the CTB 80 supernova remnant, obtained with 8-m Gemini-North telescope in 2016, and archival HST images of 1997, we measured the proper motion shift of a bright [OIII] structure ahead of the fast moving pulsar B1951+32 associated with the remnant. An arc shape of the structure suggests that it is a bow shock created by the supersonic motion of the pulsar in the ambient matter, while no direct evidence of that have been presented. The measured arc shift of ≈ 0.53″ is compatible with the pulsar proper motion shift of ≈ 0.6″ based on the radio interferometry measurements. This strongly supports the bow-shock nature of the structure.
Molecular clouds HD/H2 in the early Universe
Authors: Kosenko D N , Balashev S A
Published: December 2019

We present a simplified semi-analytical description of the relative HD/H2 abundance in the cold neutral interstellar medium. With this description we was able to obtain three asymptotics of the relative HD/H2 abundance and its dependence on physical parameters in the medium, namely, the number density of the gas, the intensity of the ultraviolet field, the cosmic ray ionization rate and metallicity. Our calculations in presented simple formalism are in the reasonable agreement with the calculations using the Meudon PDR code. We found that in the case of low metallicity and a higher cosmic ray ionization rate, the relative abundance of HD/H2 is significantly enhanced, which can explain the observed difference between the local and high-z measurements of relative HD/H2 abundance.
A search for transient events in Konus-Wind data
Authors: Kozlova A V , Svinkin D S , Lysenko A L , Ulanov M V , Tsvetkova A E , Frederiks D D
Published: December 2019

We present the search for and classification of hard X-ray and soft γ-ray transient events in the archive of continuous (waiting-mode) Konus-Wind observations. We found ∼ 26 000 transient events; among them, ∼ 12 000 are solar flares (∼ 10 times as much as observed in triggered mode); and ∼ 5 000 are gamma-ray bursts (GRBs) or soft gamma repeaters (SGRs) confirmed by other space missions (∼ 2 times as much as detected in triggered mode). The remaining ∼ 9 000 events include Galactic transients, unconfirmed GRBs and possible solar flares. We discuss the application of developed techniques for GRBs accompanied by supernovae, high-energy neutrinos and sources of gravitational waves.
Studying the γ-ray pulsar J1932+1916 and its pulsar wind nebula with Chandra
Authors: Medvedev O D , Karpova A V , Shibanov Yu A , Zyuzin D A , Pavlov G G
Published: December 2019

We report on the results of Chandra X-ray observations of the γ-ray radio-quiet pulsar J1932+1916. We confirm the previous detection of the pulsar counterpart and its pulsar wind nebula in X-rays from low spatial resolution data obtained by Suzaku and Swift. The Chandra data with much better spatial resolution resolved the fine structure of the nebula in the pulsar vicinity, which can be interpreted as jets bent by the ram pressure. The size of this compact part is about 30″, and it is surrounded by a weak asymmetric diffusive emission extended up to ≈2.′8. The X-ray spectra of the pulsar, the compact and extended parts of the nebula can be described by the power-law models with photon indexes of

0

.44

−
0.61

+
0.57

,
 2

.34

−
0.79

+
0.95

and

2.14

−
0.31

+
0.32

, respectively. The actual pulsar’s X-ray flux is several times weaker than it was obtained with Suzaku and Swift where it was dominated by the unresolved nebula. We discuss possible associations of J1932+1916 with the nearby supernova remnant G54.4−0.3.
FNS-parameterization of non-stationarity effects in the solar activity dynamics
Authors: Demin S A , Panischev O Yu , Latypov R R , Timashev S F
Published: December 2019

In paper we present the findings of analyzing the non-stationary effects to a solar activity dynamics. Within the framework of Flicker-Noise Spectroscopy (FNS) we study the Zurich series of Wolf numbers from 1849 to 2009. According to the FNS methodology the properties of complex system evolution are manifested in the low frequency component (the “resonant” part of the signal) of time signal and contain in the specific sets of the frequencies. For another thing the signal also has the high frequency component (“chaotic” part) including the noise and the different types of short time irregularities. The FNS methodology allows to discover the intermittency phenomena in studied dynamics by analyzing the behavior of the nonstationarity factor. We will show that the maximum value of this parameter corresponds the maximum of Wolf number i.e. the solar activity.
The gamma quanta absorption due to interaction to the thermal bremsstrahlung of hot gas in spheroidal galaxy cluster
Authors: Popov A N , Barsukov D P , Ivanchik A V
Published: December 2019

The interaction of high energy gamma quantum to thermal bremsstrahlung photons of hot intracluster gas with producing electron-positron pair is considered. It is supposed that gas temperature and electron number density have spheroidal distribution in galaxy cluster. The dependence of optical depth on eccentricity and orientation of spheroid is considered.
Megaelectronvolt astronomy with HERMES: spectroscopy, polarimetry, and synergies with fast Cherenkov arrays
Authors: Krassilchtchikov A M , Bykov A M , Eremin V K , Kholupenko E E , Nesterenok A V , Vasilyev G I
Published: December 2019

Sensitive observations of energetic space phenomena in the 0.3 – 10 MeV range are needed to investigate a number of hot issues of modern astrophysics and cosmology. With the advanced technology of thick double sided silicon strip detectors (Si-DSSDs) it is possible to construct a space-borne gamma-ray telescope with sensitivity 30-100 times better than that of CGRO/COMPTEL. Synergies of MeV range observations from space with GeV-TeV range spectra to be obtained with future fast and sensitive imaging atmospheric Cherenkov arrays (CTA, TAIGA-IACT, ALEGRO) would allow one to reveal complex mechanisms of energy conversion in transient gamma-ray objects, in particular, sources of gamma-ray bursts. In this short note we briefly outline most demanding objectives of 0.3 – 10 MeV range astronomy and present a schematic view of HERMES gamma-ray spectrometer being developed at the Ioffe Institute.
Isotopic imprint of the Solar system encounter with interstellar gas cloud around 660 BC (2610 BP)
Authors: Pavlov A K , Blinov A V , Frolov D A , Konstantinov A N , Koudriavtsev I V , Ogurtsov M G , Ostryakov V M , Vasilyev G I
Published: December 2019

We analyse the long lived radionuclide data (14C, 10Be and 36Cl) in tree rings and Greenland ice cores referred to the 660 BC event. The hypotheses of solar superflare impact on the atmosphere and Solar system collision with small sized dense interstellar cloud are considered. Decisive role in clarifying the situation is the experimental data on other isotope content available in ice for the periods under discussion. The data on 10Be and 36Cl (GRIP and NGRIP stations in Greenland) during the 660 BC event favour the second hypothesis. Various assumptions on the relationship between isotope production and deposition rates in the atmosphere are considered.
Experimental modeling of subsurface gas traps on Mars
Authors: Tsurkov D A , Pavlov A K , Shubina A S , Kuleshov D O
Published: December 2019

Methane seasonal variation observable by MSL mission and possible variations of atmospheric mass on timescale (105-106 years) are among the most intriguing problems in Mars exploration. These variations are connected with hypothetical biosphere activity in the subsurface Martian soil and existence of liquid water on the Martian surface within modern era. Stability of liquid water on surface request higher atmospheric pressure in comparing to modern value. CO2 cannot loss with known mechanisms of atmospheric escape. Therefore, the main part of necessary CO2 must be buried in upper layers of the Martian soil. Local and seasonal time variable sources and fast methane destruction are needed to explain high seasonal variations of methane concentration in air at the Martian surface. Gas reservoirs, containing biogenic or abiogenic methane could be possible seasonal sources of methane as well. In this work we experimental study stability of the gas reservoirs covered of mixture of regolith and water ice with perchlorates. Thickness of covered regolith layer was about 10mm. In experimental runs we increased a temperature of gas traps and monitored a possible diffusion of gases through the isolated layer with mass spectrometer. The gas traps stay stable at gas pressure up to 1 bar. We did not discover any diffusion process before mechanical destruction of reservoirs at gas pressure over 1 bar. In this work we show that the big subsurface gas reservoirs can exist for a long time before cracking due to slow process of the water ice sublimation by climate and seasonal variation of subsurface temperature.
Primordial 4He abundance refinement using sample of SDSS DR15 galaxies
Authors: Kurichin O A , Ivanchik A V , Klimenko V V
Published: December 2019

We present spectroscopic data on metal-deficient HII regions from dwarf galaxies of the Local Volume on the basis of Sloan Digital Sky Survey (SDSS) Data Release 15 observations. Using the data on the intensities of the optical emission lines of the HII regions, one can determine their chemical composition, as well as other physical properties, such as temperature and electron density. Oxygen abundance (and thus the metallicity) of the source is determined using direct method by using strong [OIII] lines. Here we present only sources with oxygen abundance below 12 + logO/H = 8.5. These data is used to determine primordial helium abundance, which value should be determined with as little errors as possibles. The main way to reduce errors is to use the spectroscopic data of the highest quality possible. On the other hand one can statistically decrease evaluation errors by using large dataset. Main focus of this paper is studying if we can decrease errors in Yp
determination by combining HeBCD sample with SDSS spectra of lower quallity.
Spectroscopic examination of dentine and gingival fluids and their diagnostic capability for the preventive treatment of pathology carious processes in dentine
Authors: Seredin P V , Goloshchapov D L , Ippolitov Yu A , Vongsvivut J
Published: December 2019

IR-spectra of the samples of the dentine and gingival fluids obtained with the use of synchrotron radiation can be applied for the diagnostics of the pathological processes of the caries character in a dentine. Vibrations within the range of 2100-2050 cm−1 observed in the spectra of dentine and gingival fluids characteristic of thiocyanates mean the development of the carious pathology. At the same time vibration modes of the carboxyl group of a complex ether detected within the range of 1765 – 1725 cm−1 in the spectra of dentine and gingival fluids certainly confirm the development of caries in dentine. These spectrometric signatures can be certainly and reliably detected also in the gingival fluid, indicating at the fact that the changes proceeding in its molecular composition are referred just to the development of pathological processes in the deep dental tissues.
Raman spectroscopic characterization of anti-diabetic drug metformin hydrochloride
Authors: Bayramov F B , Toporov V V , Chakchir O B , Anisimov V N , Rud V Yu , Glinushkin A P , Bairamov B H
Published: December 2019

Raman scattering spectra of metformin hydrochloride, one of the most widely used oral anti-diabetic drugs which also possesses anti-aging and anti-tumor properties, have been obtained by high-resolution and high-sensitivity Raman-scattering technique. It is established that rather narrow (4–10 cm–1) spectral lines of molecular vibrations are observed in of the metformin hydrochloride pressed powder sample in the important spectral range of 50–1700 cm–1. These “fingerprints” can be applied to reveal which chemical bonds produce spectral components corresponding to the vibrations of particular functional groups and the presence of crystalline state of the metformin hydrochloride without evidence of an amorphous phase. This observation makes the metformin hydrochloride as promising model system for development and application as molecular biosensors.
Investigation of the structural reorganization of micromycetes in hypomagnetic fields
Authors: Panina L K , Bogomolova E V , Dmitriev S P , Dovator N A
Published: December 2019

Using the experimental setup that allows the Earth’s magnetic field to be screened up to 1-100 nT, we found features of the microscopic fungi growth pattern, namely, the appearance of spiral growth instead of fractal. A hypothesis was put forward on the participation of a charged protein cluster - Spitzenkorper, located in the apical zone of cells, in the reorganization of fungal growth.
Analysis of stochasticity of gene expression in single cells of Mycoplasma gallisepticum
Authors: Rumyantseva N A , Vedyaykin A D , Khodorkovskii M A , Vishnyakov I E , Fisunov G Yu
Published: December 2019

Genetically identical organisms under the same conditions usually have differences in the level of expression of the same genes. This phenomenon is called genetic noise, and it is characteristic of all organisms. In this paper, we studied the stochasticity of gene expression in Mycoplasma gallisepticum at the level of single cells using fluorescence microscopy. The results show that M. gallisepticum demonstrates high level of variations in gene expression: even in case of strong promoters and ribosome-binding sites, some cells demonstrate negligible expression level. Such a high stochasticity in gene expression may have significant impact on the life of this reduced bacterium.
Analysis of the effectiveness of the stages of the concentration of genetic material
Authors: Petrov D G , Antifeev I E , Germash N N , Makarova E D
Published: December 2019

The effect of the efficiency of the stages of concentration and purification of DNA / RNA and their contribution to the efficiency of the whole process is shown. It is shown that the use of an alternating magnetic field to control the magnetic sorbent inside a liquid sample allows not only to cover the entire volume of the sample, but also to change the liquid reagents in the working chamber, thus high rates of speed and efficiency of the DNA extraction process can be achieved. Based on the data obtained earlier in studying the effect of temperature and ultrasound on the efficiency of DNA extraction, a method is proposed for increasing the efficiency of nucleic acid extraction and concentration using an alternating magnetic field.
Investigation of noise influence on calculation of fractal dimension
Authors: Kondrashov A V , Ustinov A B , Volobuev E S , Drozdovskii A V , Kalinikos B A
Published: December 2019

In this paper we investigate in details the influence of the noise intensity on the result of the fractal dimension calculation. The fractal dimension of multidimensional torus is considered as an analysis object. Sum of a number of harmonic signals with irrational ratio of their frequencies and noise signal allows to construct partially destructed torus. It is shown that the presence of the noise leads to increase of the fractal dimension. Value of the increase depends on the relation between noise intensity and harmonics intensity.
Anomalous thermal expansion of iron borate crystals FeBO3 near the Néel point
Authors: Zamkovskaya A , Maksimova E , Nauhatsky I
Published: December 2019

Study of the anomalous behavior of the linear thermal expansion coefficient near the antiferromagnetic phase transitions in iron borate crystals FeBO3 are reported. The lattice parameters and volume of FeBO3 have been measured in the temperature range 25–300˚C by the X-ray diffraction method. The thermal expansion is evidently sharply anisotropic and spike near the Néel temperature.
Issues of TRIM program as a tool for developing a silicon detectors radiation degradation scenario
Authors: Mitina D , Verbitskaya E , Eremin V
Published: December 2019

The presented study is focused around the TRIM program issues and its applications for prediction of silicon detectors degradation under heavy ions of 40Ar. Results of the simulations of low-energy ion (53.4 MeV) and high-energy ion (1.62 GeV) irradiation are demonstrated. Experimental data for silicon p+-n-n+ detectors irradiated by the low energy are also presented. Reliability of TRIM simulations application for studying silicon detectors degradation under heavy ion irradiation is discussed.
Observation of internal multiplication of nonequilibrium charge in irradiated silicon detectors at a temperature of 1.9K
Authors: Shepelev A , Eremin V , Verbitskaya E
Published: December 2019

The development of modern high-energy physics is a powerful incentive for the progress of its experimental base. The use of semiconductor devices is standard for large accelerators and experimental setups at LHC, CERN, and perspective as sensors for monitoring beam loss and radiation fields in superconducting magnets and accelerating resonators operating at superfluid helium temperature (1.9 K). In these problems, the optimal type of radiation sensor is a compact silicon detector, the use of which in harsh radiation environment in combination with helium temperatures is a non-trivial task. The most important characteristics of such devices are the distribution of the electric field in the volume and the parameters of charge carrier transport, which determines the detector signal. The study considers specific kinetics of charge collection in silicon detectors at a temperature of 1.9 K in situ irradiated by relativistic hadrons.
Computer simulation of phases consisting of Be, B and Li atoms and calculating their elastic properties using quantum mechanical calculation
Authors: Schigartsov A A , Fofanov A D
Published: December 2019

Chemical elements of groups 1 and 2 have the most pronounced properties in their periods. There is something unique about each of them, inciting substantial interest, especially regarding light-weight alloys of these elements. Young’s modulus to density ratio of beryllium is six times higher than that of steel. Heat-resistance of Be is 600°C. The combination of these physicochemical properties makes beryllium alloys specifically applicable in aerospace. Simulation of material properties is one of the main missions for materials science. Elastic properties are the easiest to calculate compared to other mechanical properties. Elastic properties are characterized by the fifth-fourth digits of the total cluster energy. Here we present the results of the calculation of the elastic constants of hexagonal and cubic beryllium and cubic lithium boride. The calculations were based on the density functional theory (DFT). The results obtained by different techniques (quantum chemical, semi-empirical) and data from the literature were compared.
Construction of the collision integral kernels for the hard spheres model
Authors: Bakaleinikov L A , Flegontova E Yu , Tropp E A
Published: December 2019

Recurrence procedure for constructing kernels of the integral operators arising in expansion of the nonlinear Boltzmann collision integral in Legendre polynomials is realised in “Mathematica” system for the hard spheres gas. All the kernels with increasing indices corresponding to the Legendre polynomials indices are subsequently calculated up to sum of indices equal to 40. The main features of the kernels as functions of their indices are considered. The kernels can be used to solve the nonlinear Boltzmann equation in strongly anisotropic case.
Exchange energy in diamagnetically diluted iron borate-based crystals
Authors: Seleznyova K , Mogilenec Yu , Strugatsky M , Yagupov S , Kliava J
Published: December 2019

The analytical relation between the microscopic a
ex and macroscopic E
dil exchange constants for diluted iron-gallium borates has been obtained. A computer code implementing a calculation of the macroscopic exchange constant for diluted iron-gallium borates has been put forward. A diamagnetically diluted crystal lattice has been generated using Monte-Carlo technique. We have found that the absolute value of the macroscopic exchange constant for diluted iron-gallium borates decreases with decreasing x, following a parabolic law.