bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heart rate variability in patients with cirrhosis: a systematic review and meta-analysis
Authors: Oyelade Tope , Canciani Gabriele , Carbone Gabriele , Alqahtani Jaber S , Moore Kevin , Mani Ali R 
Published: April 2021

Abstract

Background. Cirrhosis is associated with abnormal autonomic function and regulation of cardiac rhythm. Measurement of heart rate variability (HRV) provides an accurate and non-invasive measurement of autonomic function as well as liver disease severity currently calculated using the MELD, UKELD, or Child–Pugh scores. This review assesses the methods employed for the measurement of HRV, and evaluates the alteration of HRV indices in cirrhosis, as well as their value in prognosis. Method. We undertook a systematic review using Medline, Embase and Pubmed databases in July 2020. Data were extracted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The risk of bias of the included studies was assessed by a modified version of the Newcastle–Ottawa Scale. The descriptive studies were analysed and the standardized mean differences of HRV indices were pooled. Results. Of the 247 studies generated from our search, 14 studies were included. One of the 14 studies was excluded from meta-analysis because it reported only the median of HRV indices. The studies included have a low risk of bias and include 583 patients with cirrhosis and 349 healthy controls. The HRV time and frequency domains were significantly lower in cirrhotic patients. Between-studies heterogeneity was high in most of the pooled studies (P < 0.05). Further, HRV indices predict survival independent of the severity of liver disease as assessed by MELD. Conclusion. HRV is decreased in patients with cirrhosis compared with healthy matched controls. HRV correlated with severity of liver disease and independently predicted survival. There was considerable variation in the methods used for HRV analysis, and this impedes interpretation and clinical applicability. Based on the data analysed, the standard deviation of inter-beat intervals (SDNN) and SDNN corrected for basal heart rate (cSDNN) are the most suitable indices for prognosis in patients with cirrhosis.
Investigation of the edge ion-to-electron temperature ratio in the J-TEXT tokamak
Authors: Liu Hai , Xu Kangzhong , Xu Yuhong , Chen Zhipeng , Cheng Jun , Liu Haifeng , Wang Xianqu , Huang Jie , Zhang Xin , Shao Junren , Xiao Chijin , Tang Changjian 
Published: April 2021

Abstract
The ion (T
i) and electron (T
e) temperatures at the last closed flux surface (LCFS) during density scanning discharges and in the scrape-off layer (SOL) with a constant plasma density have been measured in the J-TEXT tokamak using a retarding field analyzer and four-tip Langmuir probe, respectively. Both the LCFS T
i and T
e are found to reduce with increasing central line-averaged density (

n
ˉ

e

). The temperature ratio (τ = T
i/T
e) is about 2 for a low

n
¯

e

(1.5 → 2.5 × 1019 m−3), decays in a moderate

n
ˉ

e

(2.5 → 3.5 × 1019 m−3) and tends to unity at a high

n
ˉ

e

(3.5 → 4.2 × 1019 m−3). This suggests that the ions and electrons at the LCFS (even in the SOL) are thermally decoupled at low or moderate

n
ˉ

e

and tend to full thermal coupling in the high-density plasmas. In addition, both T
i and T
e decrease with the radius and T
e falls more steeply than T
i due to faster parallel energy loss of electrons in the SOL. In contrast, τ rises with the radius, which indicates that the ions and electrons are much more thermally decoupled in the deeper SOL.
Photon redistribution of two-terminal perovskite/Si tandem solar cells induced by the optical coupling layer for higher power conversion efficiency
Authors: Liu Chenbo , Xi He , Yan Honghua , Yang Haifeng , Chen Dazheng , Dong Hang , Zhu Weidong , Zhang Jincheng , Zhang Chunfu , Hao Yue 
Published: April 2021

Abstract
The tandem structure is promising to break the Shockley–Queisser limit of single-junction solar cells. Optical management is essential in two-terminal (2T) tandem devices to equalize the current of each sub-cell and enhance the performance. In this work, the photon redistribution effect caused by the optical coupling layer (OCL) and its impact on 2T perovskite/Si tandem solar cells are systematically investigated. We modulate the overall optical field distribution to balance the current of the two sub-cells by structural modulation. The introduction of an OCL affects the photon distribution in the 2T tandem device, which disturbs the original current match and complicates the optical management. In addition to the antireflection function, the photon redistribution effect due to the coupling effects exists for each type of OCL. Various materials (LiF, MgF2, Al2O3 and ZnO) are employed as OCLs and compared. It is shown that they influence the device performance to different degrees. Compared to LiF and MgF2, the influence of the 2T tandem device on short-circuit current density is more significant when Al2O3 and ZnO act as OCLs. By investigating the optical mechanism and then improving the optical management, an optimized device performance can be achieved. We believe that it is necessary to consider the coupling effect in the structural design of 2T tandem solar cells.
Fatigue behavior of REBCO coated conductors under through-thickness tensile stress
Authors: Muto Shogo , Fujita Shinji , Sato Hiroki , Akashi Kazuya , Iijima Yasuhiro , Daibo Masanori 
Published: April 2021

Abstract
Fujikura Ltd has developed production techniques of REBa2Cu3O
X
(REBCO, RE = rare earth) coated conductors (CCs) using large-area ion-beam-assisted-deposition and hot-wall type pulsed-laser-deposition. We have provided high-performance REBCO CCs with long length and high homogeneity of critical current. The CCs are required to maintain their superconducting properties under mechanical stresses for a long-term. Therefore, it is important to evaluate the fatigue properties of the CCs. Although there are many investigations on cyclic tensile fatigue in the longitudinal direction of the CCs, few studies on fatigue properties in the through-thickness direction have been reported. In the case of the through-thickness stress, i.e. delamination stress, the stress is applied to the REBCO ceramic layer without substrate reinforcement, static fatigue fracture may occur by subcritical crack growth peculiar to ceramics. In this work, we carried out dynamic fatigue tests under delamination stresses at room temperature (RT) and liquid nitrogen (LN2) temperature 77 K to determine the fatigue coefficient N characterizing the static fatigue. As a result, we found that the N-value was relatively low (N ∼ 20) at RT, while the N-value was extremely high (N ∼ 150) at LN2 temperature. This result shows that the crack growth of the REBCO layer under the through-thickness tensile stress is extremely slow at low temperatures as well as that reported for bulk ceramics such as SiO2 glass. Therefore, it is expected that the static fatigue in the through-thickness direction of REBCO CC hardly occurs at low temperatures.
Multiplicity dependence in hadroproduction of heavy flavours
Authors: Siddikov Marat , Schmidt Iván 
Published: April 2021

Abstract
In this proceeding we analyze possible mechanisms of quarkonia and open-heavy flavor meson production. We study in detail the contributions of the leading twist two-pomeron fusion and higher twist corrections due to three-pomeron fusion. We show that the latter mechanism is significant for charm production at small transverse momenta. We demonstrate that recent data on the multiplicity dependence of the cross-sections might be naturally explained, both for open-heavy flavor mesons and quarkonia, if the three-pomeron contributions are taken into account.
Lighting of a monochromatic scatterer with virtual gain
Authors: Ali Rfaqat 
Published: April 2021

Abstract
In this work, we discuss the scattering features of a dipolar particle made of large refractive index material by employing the concept of virtual gain and virtual loss. The virtual gain and loss can be achieved in a lossless passive nanostructure by shaping the temporal waveform of incident signals in the complex frequency plane. We show that an appropriate tuning of excitation time of the impinging field allows to capture and release the electromagnetic energy on-demand for an arbitrary time scale in a lossless nanosphere. Thus, the nanosphere obliges to emit monochromatic magnetic light which can be tuned throughout the whole visible spectrum by varying the size of the nanosphere. This proposal may find fruitful applications in lab-on-a-chip technologies and the realization of monochromatic sectoral multipole light source with a large quality factor at nanoscale level.
Heat transfer analysis of MHD rotating flow of Fe3O4 nanoparticles through a stretchable surface
Authors: Shahzad Faisal , Jamshed Wasim , Sajid Tanveer , Nisar Kottakkaran Sooppy , Eid Mohamed R 
Published: April 2021

Abstract
The flow of a magnetite-H2O nanofluid has been considered among two rotating surfaces, assuming porosity in the upper plate. Furthermore, the lower surface is considered to move with variable speed to induce the forced convection. Centripetal as well as Coriolis forces impacting on the rotating fluid are likewise taken into account. Adequate conversions are employed for the transformation of the governing partial-differential equations into a group of non-dimensional ordinary-differential formulas. Numerical solution of the converted expressions is gained by means of the shooting technique. It is theoretically found that the nanofluid has less skin friction and advanced heat transport rate when compared with the base fluid. The effect of rotation causes the drag force to elevate and reduces the heat transport rate. Streamlines are portrayed to reveal the impact of injection/suction.
Neutrons in the classically forbidden region in neutron-rich nucleus 68Ca *
Authors: Zhu Shiwen , Zhang Ying 
Published: April 2021

Abstract
Neutrons tunneling to the classically forbidden (CF) region in the neutron-rich nucleus

are investigated in the Skyrme Hartree-Fock (HF) and Hartree-Fock-Bogoliubov (HFB) models. The definition of the CF region is examined in the HF model by using different single-particle potentials for the bound states. In the HFB model, the weakly bound and continuum states could also contribute to the neutrons in the CF region due to the pairing correlation. Their asymptotic wave functions are carefully calculated by the Green’s function method.
Type-I ELM mitigation by continuous lithium granule gravitational injection into the upper tungsten divertor in EAST
Authors: Sun Z. , Qian Y.Z. , Maingi R. , Wang Y.F. , Wang Y.M. , Nagy A. , Tritz K. , Lunsford R. , Gilson E. , Zuo G.Z. , Xu W. , Huang M. , Meng X.C. , Mansfield D.K. , Zang Q. , Zhu X. , Lin X. , Liu H.Q. , Duan Y.M. , Zhang L. , Lyu B. , Liu Y. , Wang L. , Bortolon A. , Xu G.S. , Gong X.Z. , Hu J.S. , the EAST team  
Published: April 2021

Abstract
Large edge-localized modes (ELMs) were mitigated by gravitational injection of lithium granules into the upper X-point region of the experimental advanced superconducting tokamak (EAST) device with tungsten plasma-facing components. The maximum ELM size was reduced by ∼70% in high β
N H-mode plasmas. Large ELM stabilization was sustained for up to about 40 energy confinement times, with constant core radiated power and no evidence of high-Z or low-Z impurity accumulation. The lithium granules injection reduced the edge plasma pedestal density and temperature and their gradients, due to increased edge radiation and reduced recycling from the plasma-facing components. Ideal stability calculations using the ELITE code indicate that the stabilization of large ELMs correlates with improved stability of intermediate-n peeling-ballooning modes, due to reduced edge current resulting from the profile changes. The pedestal pressure reduction was partially offset by a core density increase, which resulted in a modest ∼7% drop in core stored energy and normalized energy confinement time. We surmise that the remnant small ELMs are triggered by the penetration of multiple Li granules just past the separatrix, similar to small ELMs triggered by deuterium pellet Futatani et al (2014 Nucl. Fusion
54 073008). This study extends previous ELM elimination with Li powder injection Maingi et al (2018 Nucl. Fusion
58 024003) in EAST because (1) use of small, dust-like powder and the related potential health hazards were eliminated, and (2) use of macroscopic granules should be more applicable to future devices, due to deeper penetration than dust particles, e.g. inside the separatrix with velocities ∼10 m s−1 in EAST.
The Influence of Educational Robotics to Abstraction Skill in High School
Authors: Safrudin F M , Budiyanto C W , Yuana R A 
Published: April 2021

Abstract
The skills that individuals need to face the 21st century is computational thinking or CT. Abstraction is a major element in CT. Abstraction ability is an essential ability for students to have, but there is still little research on this ability, especially in Indonesia. If in a programming language, abstraction is the programmers action to focus on essential aspects to simplify and beautify the use of code. This article aims to determine the effect of robotics on the abstraction ability of students in secondary schools. The research results from the literature review show that robotics can improve student’s abstraction abilities. Besides, learning with robotics makes students more interested in the learning process. Educators have started to develop robotics to incorporate it into a variety of subjects. Integration of science, technology, engineering and mathematics disciplines or so-called STEM. It takes teachers who can pursue careers in the STEM field. Besides, STEM learning with robotics requires teachers to be able to explore various abilities, one of which is the abstraction ability of students. With this ability, students are expected to be able to simplify complex problems so that they are easier to solve. Future research is expected to discuss more on this topic.
Implementation of adaptive learning at higher education institutions by means of Moodle LMS
Authors: Morze N , Varchenko-Trotsenko L , Terletska T , Smyrnova-Trybulska E 
Published: April 2021

Abstract
E-learning courses have become popular means of delivering knowledge to students in higher education institutions. Most participants of learning process note that they benefit from the possibility to gain knowledge regardless of time, location and device they use. Among other advantages possibility to return to learnt material several times, divide material into parts, consume information through different types of educational materials (video, infographics, presentations, text, quizzes etc.) are mentioned. At the same time most of the surveyed students chose that they lack personalization both of materials and studying process, limited in terms of fulfillment and would like to have a choice of the level of study. The educational trend that is able to put into practice the above mentioned requirements is blended learning as it has a range of advantages such as usability, consideration of individual abilities, additional materials introduction, activities monitoring. Although it combines offline and online learning, effectiveness of e-learning courses designed for its implementation play a crucial role. To make a learning process correspondent to the students’ needs adaptive learning can be introduced in higher education institutions. Adaptive learning is a methodology that allows to identify level of students’ knowledge and their learning styles and transform materials, tasks and ways of their delivery according to the needs of learning process participants. LMS Moodle offers different solutions for adaptive learning. They provide administrators and teachers with tools to vary all stages of a learning process starting with delivery of information and ending with assessment.
Numerical analysis of Dyakonov surface-wave propagation at the interface of anisotropic and gyrotropic media
Authors: Zakharchenko M V , Glinskii G F 
Published: April 2021

Abstract
The propagation of Dyakonov surface waves was numerically investigated for the interfaces of two biaxial anisotropic media. Variation of the propagation direction changes the field energy localization from one of the partnering media to another. It is possible to find a specific propagation direction, which is characterized by the strongest energy localization in the boundary plane. This direction corresponds to the central angle of the angular existence domain. On the other hand, variation of the components of the media permittivity tensor, including the introduction of gyrotropy, changes the possible propagation directions, which is a potential way to control surface eigenmodes.
Characteristic emission from quantum dot-like intersection nodes of dislocations in GaN
Authors: Shapenkov S V , Vyvenko O F , Schmidt G , Bertram F , Metzner S , Veit P , Christen J 
Published: April 2021

Abstract
Freshly introduced a-screw dislocations in gallium nitride are an effective source of ultraviolet radiation, characterized by intense emission of narrow luminescence doublet lines in the spectral range of 3.1-3.2 eV. Furthermore, an additional narrow spectral line with an energy of 3.3 eV has been found at the points of intersection of such dislocations, where extended dislocation nodes were formed. In this communication, we report on the spectral properties of the characteristic luminescence of such nodes, which were obtained for the (0001) gallium nitride samples with dislocations introduced by nanoindentation. The spectral position of the dislocation-related luminescence doublet experiences a redshift with increasing distance from the indentation site. It follows the spectral shift of the excitonic near-bandgap emission, associated with stress relaxation. The luminescence of the intersection points exhibits a similar tendency. At certain local positions, its doublet fine structure is observed, which has a spectral linewidth of the order of or even less than that of the exciton. In this case, the spectral splitting between components of the doublet varies irregularly depending on the position of the exciton (i.e., on the mechanical stress). We see a clear indication of quantum dot-like emission. The fine structure of the luminescence of the intersection points can be easily explained by the energy dependence of emission on their size, as well as on their density, in particular, by the formation of paired nodes, which were previously observed in experiments in a transmission electron microscope.
Raman spectra of polyethylene glycol/cellulose acetate butyrate biopolymer blend
Authors: Marlina D , Novita M , Anwar M T , Kusumo H , Sato H 
Published: April 2021

Abstract
In order to investigate their crystalline structure conformations, several ratio combinations of polyethelene glycol (PEG)/cellulose acetate butyrate (CAB) were studied by Raman spectroscopy. PEG/CAB spectral features due to the composition dependence revealed the gradual transformation from crystalline PEG-like structure to the amorphous CAB-like structure as increasing the ratio of CAB. Bands appeared in the C-H stretching area of 3000– 2700 cm−1 and C-H bending area of 1500–1400 cm−1 clearly exposed the transition of the PEG to the CAB-spectral features with the transition point at about PEG/CAB (30/70). Band at 1737 cm−1 in the C=O stretching area of 1800–1650 cm−1 described the existence of a very weak hydrogen bond arise between PEG and CAB. In the C-O-C area of 1000–800 cm−1, drastic spectral change suggested that the hydrogen bond interaction takes place in the back bone of PEG.
Bacteriocin antimicrobial isolation in fish soy sauce
Authors: Darmadi N M , Edi D G S , Suryani S A M P 
Published: April 2021

Abstract
Fish sauce can be made from fermented fish. In fermentation plays a role Lactic Acid Bacteria (LAB). The role of lactic acid bacteria has a preservative effect because it can produce compounds that can inhibit the growth of various microbes. Besides lactic acid bacteria produce bacteriocin which also function as antimicrobials. The purpose of this study was to be able to isolate bacteriocin from fish sauce with SDS-PAGE electrophoresis. The study was conducted at the Laboratory of Agricultural Biotechnology Udayana University, Denpasar with a Descriptive Method. The research was carried out in sequence, namely, isolating lactic acid bacteria from fish sauce, Growing Lactic Acid Bacteria on Poor Nutrient Media so that its growth is depressed, because with life stressed Lactic Acid Bacteria can remove Bacteriocin as an Antimicrobial agent. With SDS-Page you will see separate proteins according to their weight, which are specific bands. The protein band which ranges from 17.0 kDa - 17.5 kDa is bacteriocin
Augmented reality: Physics on wave and vibration
Authors: Aji S D , Setyowati T , Jumina S , Hudha M N 
Published: April 2021

Abstract
Augmented reality (AR) is a technology that can be used in the classroom. This study aims to create an AR application and pilot the AR application in the vibrations and waves learning. Furthermore, to see if there are differences in the learning interest and physics learning outcomes by using the AR application in the learning process. The research method used to develop this application is by adapting the 4D Thiagarajan model (Define, Design, Develop, and Disseminate). The result shows there are differences in physics learning outcomes and learning interests of students studying physics using AR. AR and the use of media can be a solution for learning physics in the future.
Digital performance assessment: Measure a pharmacy physics laboratory’s skill
Authors: Dhina M A , Hadisoebroto G , Setiawati I E , Undang G , Masluh M , Mubaroq S R 
Published: April 2021

AbstractThis research is motivated by the importance of skill assessment in pharmacy physics laboratory learning. In general, laboratory skills assessments do not have a specific standard for each assessment. When students perform their performance and skills in doing practicum, they are not well observed and measured. An alternative assessment that can measure a pharmacy physics laboratory’s skill is to use a performance assessment. This study aims to design a digital performance assessment application that can be used to assess student laboratory skills. The development of a digital performance assessment application uses the Waterfall Model Software Development Life Cycle (SDLC) approach, which consists of the main stages of needs analysis, system and software design, system implementation and testing, and maintenance. The digital performance assessment design generally consists of an assessment instrument database and a user interface. Lecturers, as experts, are tasked with making assessment instruments. Meanwhile, the user interface is used by laboratory assistants/instructors to provide skill scores during student practicum. This application is then integrated with the existing web-based electronic module (e-mulsi). In the end, students can see the overall practicum score. The design of a digital performance assessment application is an alternative in a learning assessment platform that is more interesting, actual, and able to present real-time information on practicum learning in the laboratory. Policymakers are expected to consider integrating the use of these applications into a practical learning curriculum.