bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterizing the astrometric instability of extragalactic radio source positions measured with geodetic VLBI
Authors: Gattano C. , Charlot P. 
Published: March 2021

Context. Geodetic very long baseline interferometry (VLBI) has been used to observe extragalactic radio sources for more than 40 yr. The absolute source positions derived from the VLBI measurements serve as a basis to define the International Celestial Reference Frame (ICRF). Despite being located at cosmological distances, an increasing number of these sources are found to show position instabilities, as revealed by the accumulation of VLBI data over the years.
Aims. We investigate how to characterize the astrometric source position variations, as measured with geodetic VLBI data, in order to determine whether these variations occur along random or preferential directions. The sample of sources used for this purpose is made up of the 215 most observed ICRF sources.
Methods. Based on the geodetic VLBI data set, we derived source coordinate time series to map the apparent trajectory drawn by the successively measured positions of each source in the plane of the sky. We then converted the coordinate time series into a set of vectors and used the direction of these vectors to calculate a probability density function (PDF) for the direction of variation of the source position. For each source, a model that matches the PDF and that comprises the smallest number of Gaussian components possible was further adjusted. The resulting components then identify the preferred directions of variation for the source position.
Results. We found that more than one-half of the sources (56%) in our sample may be characterized by at least one preferred direction. Among these, about three-quarters are characterized by a unique direction, while the remaining sources show multiple preferred directions. The analysis of the distribution of these directions reveals an excess along the declination axis that is attributed to a VLBI network effect. Whether single or multiple, the identified preferred directions are likely due to source-intrinsic physical phenomena.
Research of security and safety culture within an organization. The case study within the Slovak Republic
Authors: Veľas Andrej , Halaj Martin , Hofreiter Ladislav , Kampová Katarína , Zvaková Zuzana , Jankura Richard 
Published: March 2021

AbstractSecurity and safety culture is an increasingly important term in assessing the security and safety of organizations. It is an internal security and safety factor of an organization that can directly influence its overall security and safety. In many cases, however, organizations do not know, nor do they have a way of assessing the level of their security and safety culture. It is therefore necessary to know the content, elements, and sectors in which it can be identified in order to gain a deeper knowledge of security and safety culture in more detail and be able to examine it. Firstly, we focused on creating a model for evaluating the safety and safety culture and its application in selected organizations. Secondly, we devoted to the description and design of an organization’s security and safety culture assessment model. The proposed model is based on the identification of subsectors and indicators of security and safety culture that will gain their value by using information obtained from combining the four proposed methods. Accordingly, six security and safety culture sectors were defined for the purposes of security and safety culture assessment in selected organizations. These were compared to each other to determine their mutual weight. Finally, using these research methods, security and safety culture indicators were also identified and included in the defined security and safety culture sectors. The research needed to design a security and safety culture assessment model was realized in six selected organizations, which wanted to participate in the research. These were divided according to the size of the organization into two small, two medium, and two large organizations. Crucial element in our research was data collection conducted by means of controlled interviews and questionnaire surveys in these organizations. Based on this survey, indicators of security and safety culture could be identified. As a result of this, security and safety culture values are determined for all analyzed organizations. The conclusions will point up the possible way of evaluating security and safety culture in organizations and it also contains a specific example of their usage in the practice. Thus, by using the resulting values, it is possible to decide the further direction for the organizations, focusing on the sectors of the security and safety culture, which yielded unsatisfactory results.
A low noise transimpedance amplifier for optical receiver
Authors: Li Chenming , Xie Sheng , Zhou Gaolei , Mao Luhong , Qiu Bowen 
Published: March 2021

In this paper, a regulated cascode (RGC) structure and a shunt-feedback transimpedance amplifier are cascaded. By analyzing the average input-referred noise current, this paper used the method of adjusting the metal–oxide–semiconductor size and increasing the transimpedance gain to optimize the circuit noise characteristics without introducing redundant structures and noise sources. The measured results demonstrated that when the photodetector capacitance is 300 pF and the supply voltage is 1.8 V, the fabricated transimpedance amplifier has a transimpedance gain of 59.5 dBΩ and a −3 dB bandwidth of 4 GHz. Simultaneously, the average input-referred noise current spectral density is less than 7 pA/√Hz, and the data rate is as high as 5 Gb/s. The circuit takes advantage of the traditional shunt-feedback transimpedance amplifier and introduces a RGC structure between it and the input terminal as a current buffer structure. A π-type matching network was formed by adding an inductor between the shunt-feedback amplifier and the introduced RGC. All these structures can effectively improve the gain–bandwidth product of the designed amplifier.
Zinc finger protein E4F1 cooperates with PARP-1 and BRG1 to promote DNA double-strand break repair
Authors: Moison Céline , Chagraoui Jalila , Caron Marie-Christine , Gagné Jean-Philippe , Coulombe Yan , Poirier Guy G. , Masson Jean-Yves , Sauvageau Guy 
Published: March 2021

Significance
Cycling cells acquire numerous DNA lesions under physiological conditions and thus require functional DNA damage response (DDR) pathways to support proper DNA repair. Hundreds of proteins orchestrate the DDR in time and space from very early events, such as the sensing of DNA lesions by DNA-dependent poly(ADP-ribose) polymerases (PARPs) to late steps in chromatin restoration. Here we define a function of E4F1 in double-strand break repair. We show that E4F1 is rapidly recruited to DNA lesions by PARP-1, where it promotes γH2AX clearance, transcriptional silencing, DNA-end resection, and homologous recombination. These data provide an unsuspected molecular explanation for the essential role of E4F1 in DDR-associated cell cycle arrest and survival.
Macrophage activation syndrome in patients with adult-onset Still’s disease under tocilizumab treatment: A single-center observational study
Authors: Yamabe Toru , Ohmura Shin-ichiro , Uehara Koji , Naniwa Taio 
Published: March 2021

Abstract

Objectives
Macrophage activation syndrome (MAS) developed under tocilizumab treatment poses a diagnostic challenge. This study aims to demonstrate the frequency and the clinical features of MAS developed in patients with adult-onset Still’s disease (AOSD) receiving tocilizumab.

Methods
The consecutive AOSD patients treated with tocilizumab in our institution from April 2008 to March 2020 were studied. The frequency of clinically diagnosed MAS during tocilizumab treatment, their conformity to the several criteria relevant for MAS, and laboratory characteristics compared to AOSD flare were investigated.

Results
Of the 20 AOSD patients treated with tocilizumab, six developed clinically diagnosed MAS, four immediately after starting tocilizumab and two after long-term treatment. Some of them had already met the MAS criteria before starting tocilizumab. At MAS diagnosis, although some did not meet the MAS criteria due to lack of fever and/or the lower ferritin levels, all consistently showed sharp increases in ferritin along with marked abnormal changes in two or more different markers of organ damage, unlike the AOSD flares.

Conclusion
MAS is not a rare complication in AOSD patients receiving tocilizumab. The clinical similarities between systemic AOSD and MAS, and substantial alterations in MAS features by inhibition of interleukin-6 signaling may limit the utility of the existing diagnostic/classification criteria in diagnosing MAS under tocilizumab treatment. The emergence of abnormalities in MAS-related organ damage markers with a rapid elevation of ferritin should be considered as MAS development in AOSD patients receiving tocilizumab even if the patients are afebrile or have relatively low ferritin levels.
Addendum: Measurement of emissivity in student laboratories (2020 Eur. J. Phys.
41 015101)
Authors: Ficker T 
Published: March 2021

Abstract
In the preceding paper Ficker (2020 Eur. J. Phys.
41 015101 https://doi.org/10.1088/
1361-6404/ab4c1e), two alternative methods for measuring emissivity of opaque grey diffuse materials have been presented. In both these methods, the contactless temperature measured by the infrared thermometer has been employed. The thermometer has been set at emissivity ɛ = 1 chosen in the settings menu of the thermometer. This ideal value has been incorporated into the derived relations determining emissivity of material samples. However, no infrared thermometer can work with such an ideal value due to the calibration restrictions during its manufacturing. Thus, a modification of the measured values of contactless temperatures is desirable. The present addendum specifies the corresponding modification of the contactless temperature used in the suggested experimental methods.
Novel double negative curvature elliptical aperture core fiber for terahertz wave transmission
Authors: Meng Miao , Yan Dexian , Yuan Ziwei , Feng Qinyin , Li Xiangjun , Qiu Guohua , Li Jining , Li Jiusheng 
Published: March 2021

Abstract
A novel double negative curvature terahertz fiber with elliptical tubes as cladding structure is designed and investigated. Six uniformly arranged elliptical hole tubes and six circular tubes are connected to each other as the cladding structure of the fiber. The confinement loss, bending loss, dispersion, and effective mode field area of the fiber are calculated in two different frequency regions. The simulation shows that the lowest confinement loss of 3.2 × 10−6 dB cm−1 can be achieved at 2.44 THz. The confinement loss is always in the order of 10−5–10−6 dB cm−1 in the frequency band of 2.22–2.5 THz. The waveguide dispersion of fiber remains between −0.18 and 0.05 ps/(THz × cm) in the frequency band of 2.04–2.4 THz. Moreover, the bending loss of 4.4 × 10−5 dB cm−1 can be obtained when the bending radius is 25 cm. The debut of this double negative curvature terahertz fiber, with combined advantages of ultralow confinement loss, low bending loss, low and flat dispersion and simple structure forebodes a new approach to completely release the potential of fiber in terahertz applications.
Phase-space sensitivity (weight functions) of 3 MeV proton diagnostics
Authors: Heidbrink W W , Garcia A , Boeglin W , Salewski M 
Published: March 2021

Abstract
The weight function W(X) is a diagnostic sensitivity to phase-space variables X that relates the measured signal C to the distribution function F(X) through the equation

C
=
∫
W
(
X
)
F
(
X
)
d
X

. In the present work, an algorithm to calculate W for a diagnostic that measures 3 MeV protons produced in d(d,p)t fusion reactions between a fast ion and a thermal deuteron is developed. The emitted protons escape the tokamak on curved orbits and are detected. These curved orbits constitute effective diagnostic ‘sightlines’. The presented algorithm accounts for the complications associated with these curved sightlines. An initial calculation of time-reversed proton orbits computes effective solid angles and sightlines for the relevant range of incident proton velocity vectors. These precomputed orbits are then used within the framework of FIDASIM (2020 Plasma Phys. Cont. Fusion
62 105008) to calculate the reactivity averaged over the thermal distribution of the ‘target’ deuterons and the probability that a fast ion of specified energy and pitch has a gyroangle that is consistent with the kinematic equations along each of the sightlines. Comparisons with analytic formulas and with independent calculations for the Mega Amp Spherical Tokamak 3 MeV proton diagnostic verify the algorithm.
High order plasmonic vortex generation based on spiral nanoslits
Authors: Fang Jing , Zhou Changda , Mou Zhen , Wang Shuyun , Yu Jiayi , Yang Yuanjie , Gbur Gregory J , Teng Shuyun , Cai Yangjian 
Published: March 2021

Abstract
Highly localized plasmonic vortices carrying orbital angular momentum are of importance for many applications. Yet, it is a challenge to generating plasmonic vortex with a high topological charge because of no available technique. Here, a novel plasmonic vortex generator is proposed based on spiral nanoslits etched in a metal film, which can produce a high order plasmonic vortex. The consecutive spiral nanoslit can generate plasmonic vortex with high intensity and the segmented nanoslits enhances the controllability of the plasmonic vortex, which are demonstrated numerically and experimentally. High order plasmonic vortex generation will broaden the prospects for plasmonic vortices in practical applications for nanomanipulation and nanofabrication.
A color image encryption algorithm based on an improved Hénon map
Authors: Gao Xiaohong 
Published: March 2021

Abstract
Chaos is widely used in secure communication and cryptography due to its randomness, unpredictability, non-periodicity and high sensitivity to initial values and parameters. However, there are many risks in some existing chaotic image encryption algorithms because they use the the chaotic map without complex dynamic characteristics. To overcome these weaknesses, in this paper introduced an improved Hénon map, and the dynamic analysis results show that the improved Hénon map has more rich chaotic behaviors and better complexity. In addition, we designed a color image encryption scheme using the improved Hénon sequences. For this encryption algorithm, color image is divided into R, G, B primary colors, then R, G, B primary colors are scrambled and diffused by the improved Hénon sequences. The simulation results illustrate that color image encryption algorithm security is advanced by usingimproved Hénon map.
The P-branch high-lying rovibrational transition spectral lines of BiLi molecule
Authors: Lei Jiao , Fan Qun Chao , Li Bao Lin , Fan Zhi Xiang , Fu Jia , Ma Jie , Xie Feng , Li Hui Dong , Xu Yong Gen 
Published: March 2021

Abstract
Starting from the classical expression of the rovibrational transition spectra of diatomic molecule, the Difference Converging Method (DCM) is used again to derive a new convenient and easy-to-use analytical formula for predicting the P-branch transitional spectral lines in the highly rovibrational excited states of diatomic molecule. Based on the limited experimental low-lying transition spectra the emission spectral lines up to the rotational quantum number

J
=
80

of (0–0) band in the

A

Π

3

A

2

0

+

→

X

3

∑

−

X

1

0

+

,

X

2

1

transition systems of BiLi molecule are predicted and studied. The accuracy of prediction is analyzed in detail by using the prediction error Δδ, which gives a quantitative conclusion for the reliability of prediction data. Compared the data obtained by DCM method with experimental ones, and analyzed the

v

E
x
p
t

−

v

D
C
M

,

Δ

E
x
p
t

,

Δ

D
C
M

,

Δ
δ

in deeply, the results show that the DCM method can use 11 known P-branch emission spectral lines to reliably reproduce the experimental values and accurately predict the high-excited transition spectral lines which may be difficult obtained in the experiment. It provides a new method to solve the problem of lack of high excited state transition spectra of diatomic molecules and the application of molecular spectrum in other fields.
Photoresponsive characteristics of EFG-grown iron-doped (100) Ga2O3 substrate with low dark current
Authors: Chu Xulong , Liu Zeng , Zhang Shaohui , Li Peigang , Tang Weihua 
Published: March 2021

Abstract
Low dark current is more desired in photodetector, that contributes to high photo-to-dark current ratio and high sensitivity. Therefore, in this paper, we use the edge-defined-film-fed (EFG)-grown iron (Fe)-doped Ga2O3 substrate to fabricate a solar-blind ultraviolet (UV) photodetector. Fortunately, the photodetector shows a low dark current of ∼10–13 A, which are more promised to advance the solar-blind photodetections. The responsivity (R) of 0.145 mA W−1, specific detectivity (D*) of 6

×

1010 cm Hz1/2 W−1 (Jones), linear dynamic region (LDR) of 75.56 dB and rise/decay time of 0.28 s/0.43 s are achieved in this Fe-doped β-Ga2O3 solar-blind UV photodetector.
Impact of internal-delensing biases on searches for primordial 𝖡-modes of CMB polarisation
Authors: Baleato Lizancos Antón , Challinor Anthony , Carron Julien 
Published: March 2021

Abstract
Searches for the imprint of primordial gravitational waves
in degree-scale CMB B-mode polarisation data must account for
significant contamination from gravitational lensing. Fortunately,
the lensing effects can be partially removed by combining
high-resolution E-mode measurements with an estimate of the
projected matter distribution. In the near future, experimental
characteristics will be such that the latter can be reconstructed
internally with high fidelity from the observed CMB, with the
EB quadratic estimator providing a large fraction of the
signal-to-noise. It is a well-known phenomenon in this context that
any overlap in modes between the B-field to be delensed and the
B-field from which the reconstruction is derived leads to a
suppression of delensed power going beyond that which can be
attributed to a mitigation of the lensing effects. More importantly,
the variance associated with this spectrum is also
reduced, posing the question of whether the additional power
suppression could help better constrain the tensor-to-scalar ratio,
r. In this paper, we show this is not the case, as suggested but not quantified in previous work.
We develop an analytic model for the biased delensed B-mode angular power spectrum, which suggests a simple renormalisation prescription to avoid bias on the inferred tensor-to-scalar ratio. With this approach, we learn that the bias necessarily leads to a degradation of the signal-to-noise on a primordial component compared to “unbiased delensing”. Next, we assess the impact of removing from the lensing reconstruction any overlapping B-modes on our ability to constrain r, showing that it is in general advantageous to do this rather than modelling or renormalising the bias. Finally, we verify these results within a maximum-likelihood inference framework applied to simulations.
Improving helium abundance determinations with Leo P as a case study
Authors: Aver Erik , Berg Danielle A. , Olive Keith A. , Pogge Richard W. , Salzer John J. , Skillman Evan D. 
Published: March 2021

Abstract
Currently, the primordial helium abundance is best estimated
through spectroscopic observations of H II regions in
metal-poor galaxies. However these determinations are limited by
several systematic uncertainties which ultimately limit our ability
to accurately ascertain the primordial abundance. In this study, we
improve the methodologies for solving for the reddening, the
emission contributions from collisional excitation of the H I
atoms, the effects underlying absorption in the H I and
He I emission lines, and the treatment of the blended H I and He I emission at λ3889 with the aim of
lowering the systematic uncertainties in helium abundance
determinations. To apply these methods, we have obtained
observations of the He I λ10830 emission line in the
brightest H II region in the extremely metal-poor (3%
Z⊙) galaxy Leo P with the LUCI1 instrument on the LBT. We
combine this measurement with previous MODS/LBT observations to
derive an improved helium abundance. In doing so, our present
analysis results in a decrease in the uncertainty in the helium
abundance of Leo P by approximately 70%. This result is combined
with data from other observations to estimate the primordial helium
mass fraction, Yp= 0.2453 ± 0.0034.
EEG-inception: an accurate and robust end-to-end neural network for EEG-based motor imagery classification
Authors: Zhang Ce , Kim Young-Keun , Eskandarian Azim 
Published: March 2021

Abstract

Objective. Classification of electroencephalography (EEG)-based motor imagery (MI) is a crucial non-invasive application in brain–computer interface (BCI) research. This paper proposes a novel convolutional neural network (CNN) architecture for accurate and robust EEG-based MI classification that outperforms the state-of-the-art methods. Approach. The proposed CNN model, namely EEG-inception, is built on the backbone of the inception-time network, which has showed to be highly efficient and accurate for time-series classification. Also, the proposed network is an end-to-end classification, as it takes the raw EEG signals as the input and does not require complex EEG signal-preprocessing. Furthermore, this paper proposes a novel data augmentation method for EEG signals to enhance the accuracy, at least by 3%, and reduce overfitting with limited BCI datasets. Main results. The proposed model outperforms all state-of-the-art methods by achieving the average accuracy of 88.4% and 88.6% on the 2008 BCI Competition IV 2a (four-classes) and 2b datasets (binary-classes), respectively. Furthermore, it takes less than 0.025 s to test a sample suitable for real-time processing. Moreover, the classification standard deviation for nine different subjects achieves the lowest value of 5.5 for the 2b dataset and 7.1 for the 2a dataset, which validates that the proposed method is highly robust. Significance. From the experiment results, it can be inferred that the EEG-inception network exhibits a strong potential as a subject-independent classifier for EEG-based MI tasks.
HAT ALARM SYSTEM TO PROTECT EYES, NOSE AND MOUTH FROM CORONA VIRUS CONTAMINATED HAND
Authors: Chatterjee Sarthak , Pal Saikat , Dey Sankha , Chowdhuri Swati , Sen Sabyasachi , Neogi Biswarup 
Published: March 2021

Abstract
Self-inoculation takes major part for the transmission of infections. Basically self-inoculation is nothing but a type of contact transmission. A person’s contaminated hands make contact with other parts of the body by Self-inoculation. Many infections mainly respiratory infections (e.g., influenza, coronavirus) can transmit via self-inoculation. In this pandemic situation it is very necessary to resist the transmission of infection (corona virus) via self-inoculation. In this paper a module of personal protective intelligent hat has been proposed for the protection of human being. The protective intelligent hat fabricates with two ends (i) Face Side End System (FSES) and (ii) Hand Side End System (HSES). FSES is made up with hall sensor whereas HSES is set up with magnet set ring or band. The novel corona virus enters the human body by eyes, nose and mouth when all are touched by infected hand. Avoid touching of contaminated hand is one of the key to survive from the attack of corona virus as well as other bacteria. The smart hat not only applicable to protect COVID-19, it is also applicable to protect various diseases which caused by contaminated hand like Influenza, Common cold, Chicken Pox etc.