bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapport management strategies among the Yoruba people of Southwestern Nigeria
Authors: Omotunde Samuel Adebayo , Ogunrotimi Olumide 
Published: March 2021

Abstract
This paper investigates the rapport management strategies among the Yoruba people of Southwestern Nigeria using Spencer-Oatey’s rapport management model. The authors relied on participant observation and overheard conversations in writing the paper. They are effectively equipped to write the work because they were born and bred in Yorubaland, hence, they are able to watch all the rapport management strategies at all relevant levels. Our findings reveal that five major rapport strategies are in operation in Yorubaland which are: use of selected nominal address forms by housewives to address family members; acknowledging the sociality rights and obligations of elders in-council by the king/chief; paying homage to elders by younger interlocutors before rendering proverbs; using indirectness and statement of consideration when interacting with elders on some issues; and lastly, proper deployment of non-verbal communication.
Gender Differences among Criminal Justice-Involved Persons Living with HIV Interested in Extended-Release Naltrexone Treatment
Authors: Biondi Breanne E. , Frank Cynthia A. , Forray Ariadna , Springer Sandra A. 
Published: March 2021

Background Previous research has shown gender differences with respect to entry into medication treatment of substance use disorders (SUDs), yet few have examined gender differences among participants consented to be treated with extended-release naltrexone (XR-NTX). Understanding gender differences is critical to developing interventions to overcome barriers to initiation of and retention on medication treatment for SUDs. Methods Data from two double-blind placebo-controlled trials of XR-NTX among persons with HIV and alcohol or opioid use disorders leaving the criminal justice system (CJS) were analyzed for gender differences among clinical characteristics, mental health, drug use severity, and other domains. The study that recruited persons with alcohol use disorder (AUD) was conducted from September 2010–February 2016 at two sites in Connecticut (CT), and the opioid use disorder (OUD) study was conducted from September 2010–March 2016 at three sites in CT and one site in Massachusetts. Results Baseline data were analyzed from 193 participants consented to be randomized to XR-NTX or placebo; 40 women and 153 men. Women were younger, had worse mental health severity, and were more likely to be diagnosed with cocaine use disorder. There were no statistical differences between men and women in the prescription of antiretroviral therapy (ART) or ART adherence. Conclusions Women had greater mental health severity and a higher prevalence of cocaine use as compared to men, both of which are known to be barriers to engagement and retention on medication treatment for alcohol and opioid use disorders. For women with CJS involvement and living with HIV and SUDs, understanding factors that may affect initiation and retention on medication treatment of SUDs are necessary to improve treatment outcomes in women.
An International Consultation on Case Reports in Addiction Medicine
Authors: Qurishi Rouhollah , Drenth Joost P. H. , Baldacchino Alexander , Broers Barbara , Buwalda Victor J. A. , De Jong Cornelis A. J. 
Published: March 2021

Background A Case Report (CR) is a scientific documentation of a single clinical observation which serves to inform but also to educate the reader. Case reports help to compliment clinical critical thinking in Addiction Medicine (AM) when there is limited evidence base. Aim: This study aims to analyze how international clinical and research leaders in Addiction Medicine view Case Reports and their relevance to bridge the gap between evidence and practice. Methods A semi-structured, audio-recorded interviews were conducted with 12 international Addiction Medicine scholars. Thematic content analysis was used to code the transcribed interview data. Results Interviewees showed a positive view toward publishing Case Reports in Addiction Medicine. They found that medical students and clinicians working in the field of Addiction Medicine should be encouraged to share and record cases of clinical interaction. To aid this process (1) formal supervised training in case reporting within an academic environment must be facilitated. And (2) journals should also offer a place to publish Case Reports. Conclusion The international scholars agree that Case Reports are important for the development of Addiction Medicine and that they can contribute to a better understanding of patients with substance use disorder.
On a three-dimensional Compton scattering tomography system with fixed source
Authors: Cebeiro J , Tarpau C , Morvidone M A , Rubio D , Nguyen M K 
Published: March 2021

Abstract
Compton scattering tomography is an emerging scanning technique with attractive applications in several fields such as non-destructive testing and medical imaging. In this paper, we study a modality in three dimensions that employs a fixed source and a single detector moving on a spherical surface. We also study the Radon transform modeling the data that consists of integrals on toric surfaces. Using spherical harmonics we arrive to a generalized Abel’s type equation connecting the coefficients of the expansion of the data with those of the function. We show the uniqueness of its solution and so the invertibility of the toric Radon transform. We illustrate this through numerical reconstructions in three dimensions using a regularized approach.
Luminescence of ZnO nanocrystals in silica synthesized by dual (Zn, O) implantation and thermal annealing
Authors: Parkhomenko I , Vlasukova L , Komarov F , Makhavikou M , Milchanin O , Wendler E , Zapf M , Ronning C 
Published: March 2021

Abstract
Zinc blende ZnO nanocrystals (NCs) were synthesised in amorphous silica by high-fluence dual (Zn, O) ion implantation and subsequent thermal annealing in air. We observed the formation of core/shell nanoparticles at the depth of maximum Zn concentration as a result of an incomplete oxidation process. The silica matrix with ZnO NCs exhibits an intense white-greenish emission. Low-temperature photoluminescence spectroscopy revealed various radiative recombination mechanisms in the zinc blende ZnO NCs involving intrinsic defects that act as donors and acceptors.
Electrocaloric effect enhancement in compositionally graded ferroelectric thin films driven by a needle-to-vortex domain structure transition
Authors: Van Lich Le , Hou Xu , Phan Manh-Huong , Quoc Bui Tinh , Wang Jie , Shimada Takahiro , Kitamura Takayuki , Dinh Van-Hai 
Published: March 2021

Abstract
Obtaining large electrocaloric (EC) effects in ferroelectric materials is a prerequisite for incorporating them into advanced solid-state cooling devices. Based on phase-field simulations, we propose an effective approach for improving the EC effect near room temperature in compositionally graded ferroelectric (CGFE) thin films (e.g., Pb1 − x
Sr
x
TiO3) by controlling the compositional gradient along the direction of the thickness of the films. The simulation results reveal the formation of a stable needle-like domain structure in CGFE films with large composition gradients, while a periodic striped domain structure is found in small-composition-gradient CGFE films. The temperature dependence of polarization can be tailored by controlling the composition gradient in the films. With rising temperatures, a notable transition from a needle-like to a vortex domain structure is observed in CGFE films, which is distinguishable from that observed in homogeneous ferroelectric films. Our work demonstrates that the EC effect (the adiabatic temperature change, ΔT) can be greatly improved by the needle-to-vortex domain transition that occurs when the composition gradient is increased. When the composition gradient increases, a larger EC effect is achieved at lower temperatures. Large-composition-gradient films exhibit multiple peaks of ΔT. The local concentration of the total energy near the root of the needle domains is also found to drive the needle-to-vortex domain transition, giving rise to an enhancement of the EC effect in CGFE films. Our study provides a potential pathway for designing ferroelectric thin films with enhanced EC properties for energy-efficient solid-state refrigeration.
Origin of ferroelectricity in cubic phase of Hf substituted BaTiO3
Authors: Sati Aanchal , Pokhriyal Preeti , Kumar Anil , Anwar Shahid , Sagdeo Archna , Lalla N P , Sagdeo P R 
Published: March 2021

Abstract
The origin of ferroelectricity in the cubic phase of BaTi1−x
Hf
x
O3 has been investigated. The presence of well-defined ferroelectric polarization versus electric field (PE) hysteresis loop in the samples with global cubic symmetry suggests the presence of ‘local polar regions’, induced possibly due to the huge difference in the electronegativity and also difference in the ionic radii of Hf+4 and Ti+4 ions, which may lead to local structural disorder. The presence of polar regions is also supported through the appearance of A1(TO) polar mode in Raman spectra which in principle should be absent in the samples with cubic symmetry. The results are discussed in terms of disorder-induced local dipoles due to the electronegativity difference between Hf and Ti ions.
Perpendicular and in-plane hole asymmetry in a strained NiFe2O4 film
Authors: Knut R , Malik R S , Kons C , Shoup J E , Radu F , Luo C , Kvashnin Y O , Gupta A , Karis O , Arena D A 
Published: March 2021

Abstract
Strained materials can exhibit drastically modified physical properties in comparison to their fully relaxed analogues. We report on the x-ray absorption spectra (XAS) and magnetic circular dichroism (XMCD) of a strained NiFe2O4 inverse spinel film grown on a symmetry matched single crystal MgGa2O4 substrate. The Ni XAS spectra exhibit a sizable difference in the white line intensity for measurements with the x-ray electric field parallel to the film plane (normal incidence) vs when the electric field is at an angle (off-normal). A considerable difference is also observed in the Fe L
2,3 XMCD spectrum. Modeling of the XAS and XMCD spectra indicate that the modified energy ordering of the cation 3d states in the strained film leads to a preferential filling of 3d states with out-of-plane character. In addition, the results point to the utility of x-ray spectroscopy in identifying orbital populations even with elliptically polarized x-rays.
On the flat galactic rotational curves in f(R) gravity
Authors: Usman Muhammad 
Published: March 2021

Abstract
A mysterious dark matter is supposed to exist in the galactic halos. In this contrast, we discuss the possibility of explaining the flat rotational velocity curves in f(R) gravity by solving field equations numerically in vacuum and for different matter distributions. For a spherically symmetric static space-time (as the galactic environment) we give metric for constant rotational velocity regions. For a constant rotational velocity region, we prove that all values of rotational velocities (most importantly observed rotational velocity 200–300 Km/s) do not lead to an analytic solution of the vacuum field equations. We then obtain numerical solutions of the field equations in vacuum and for three types of mass distributions named: (1) power law density profile, (2) simple model for galaxy with a core and, (3) Navarro, Frank and White (NFW) profile, for M31 and Milky way galaxy. The solutions suggest a slight modification from linear relations from R for vacuum whereas a significant deviation from R for the distributions can give flat rotational curves. Using Brans-Dicke theory, we also relate obtained modified gravity function with the equivalent scalar fields, the procedure gives us very interesting phenomena and behavior of dark matter in the galactic environment. We observe that the scalar dark matter, coming from different modified gravity functions of matter profiles, does not accumulate as the baryonic matter. These results then can be used to explain the spatial offset of the center of the total mass from the center of the baryonic mass peaks of the bullet cluster and Abell-520.
Monte Carlo simulation variance reduction techniques for photon transport in liquid xenon detectors
Authors: Bruenner S. , Colijn A.P. , Decowski M.P. , Kesber O.V. 
Published: March 2021

Abstract
Monte Carlo simulations are a crucial tool for the analysis and prediction of various background components in liquid xenon (LXe) detectors. With improving shielding in new experiments, the simulation of external backgrounds, such as induced by gamma rays from detector materials, gets more computationally expensive. We introduce and validate an accelerated Monte Carlo simulation technique for photon transport in liquid xenon detectors. The method simulates photon-induced interactions within a defined geometry and energy range with high statistics while interactions outside of the region of interest are not simulated directly but are taken into account by means of probability weights. For a simulation of gamma-induced backgrounds in an exemplary detector geometry we achieve a three orders of magnitude acceleration compared to a standard simulation of a current ton-scale LXe dark matter experiment.
Oscillatory stability of quantum droplets in



-symmetric optical lattice
Authors: Lao Jiehong , Zhou Zheng , Zhang Xili , Ye Fuqiu , Zhong Honghua 
Published: March 2021

Abstract
We study stability and collisions of quantum droplets (QDs) forming in a binary bosonic condensate trapped in parity-time (




)-symmetric optical lattices. It is found that the stability of QDs in the




-symmetric system depends strongly on the values of the imaginary part W
0 of the




-symmetric optical lattices, self-repulsion strength g, and the condensate norm N. As expected, the




-symmetric QDs are entirely unstable in the broken




-symmetric phase. However, the




-symmetric QDs exhibit oscillatory stability with the increase of N and g in the unbroken




-symmetric phase. Finally, collisions between




-symmetric QDs are considered. The collisions of droplets with unequal norms are completely different from that in free space. Besides, a stable




-symmetric QDs collides with an unstable ones tend to merge into breathers after the collision.
The Difference of The Enhancement of Students’ Mathematical Disposition as an Impact of ARCS-based Learning Model and Conventional Approach
Authors: Syahputra E , Surya E , Putra P D 
Published: March 2021

Abstract
This study aims to identify the enhancement of Students’ Mathematical Disposition as an impact of ARCS-Based Learning Model approach. The learning model based on Attention, Relevance, Confidence and Satisfaction (ARCS) theory. This study is a quasi experimental study. The study sample consisted of 76 students from 2 classes mathematics in the seventh semester in Universitas Negeri Medan. Instrument used in this study is mathematical disposition scale. Data were analyzed using Mann Withney, ttest, correlation analysis, one way and two way ANOVA followed by posthoc test. The result showed that the enhancement of students disposition of high initial ability group is significantly higher than middle and low initial ability group. This shows that ARCS-Based Learning Model provides the highest enhancement of students’mathematical disposition in the high initial ability group compared to the middle and low ones. Overall, based on students initial ability, ARCS-Based Learning Model approach is significantly able to enhance students’mathematical disposition.
The Effect of Guided Inquiry-based Learning with Creative Thingking Ability towards Students’ Scientific Process Skill in Analytical Chemistry Courses
Authors: Juniar Anna , Silalahi Albinus , Suyanti Retno Dwi 
Published: March 2021

Abstract
Indonesian National Qualification Framework requisite on students’ scientific process skill in analytical chemistry courses is difficult to be satisfied since the content is loaded with calculation and applicative discovery. Overcoming this challenge, investigative study of guided inquiry-based learning with creative thingking ability towards students’ scientific process skill in analytical chemistry courses was done. The implementation was done towards 56 pre-service chemistry teachers. As comparison, conventional learning model was done towards 26 pre-service chemistry teachers using th same courses. The effectivenes was measured using pre and post-test which consisted of fifteen valid and reliable essay items. For statistical analysis of variance (ANOVA) was used and resulted students’ scientific process skill which taught by using guided inquiry-based learning is better than conventional class, especially for upper group of creative thingking ability with average of postest in experimental class is 31.11 meanwhile control class is 18.08 from maximum score is 39. The interaction between learning model with creative thingking model and students’scientific process skill was significant with probability 0.04 lower than selected alpha 0.05. According to these results, innovation of guided inquiry-based learning with creative thingking ability is recommended to improve students’ scientific process skill especially for chemistry courses.
STEM-based Project for Everyday Life Created by Pre Service Students and Its Implication of Pedagogical Competence for Science Teacher
Authors: Djulia E , Simatupang H 
Published: March 2021

Abstract
STEM Education has become framework of lifelong, life-wide, and life-deep across the word in Science Education. Some research investigated about how student comprehend science concept and its related into technology, engineering and mathematics lead to science conception in more deep insight. Pre service science teacher has important role to build and disseminate STEM approaches into science teaching practices. This study aims to investigate how preservice science teacher create STEM- based project concerning on essential science concepts. About 72 pre service students of Science Education Study Program in STEM course involved in this study who work in group of four students each. During eight weeks they begin with group discussion, group presentation to share their project idea, supported with journal review, preparing project, designed first project, peer review, improving project until finalizing projects. About eight from eighteen titles of their projects have been selected to be deeply analyzed further because of similar based science concept referred to changes in electrical energy into motion in some various project they created. The title projects are: a) electric broom; b) simple mixer; c) mini vacuum cleaner; d) Air conditioner recharge; e) blender; f) earth rotation; g) locomotive; h) mini generator. Based on group discussion, group review, and interview there were found seven kinds of their understanding of STEM begin with lack explanation of scientific reason, theoretical explanation only, good explanation of scientific reason, ability to apply STEM in daily life, lack implementation of Reduce-reuse-recycle, and good implementation of reduce-reuse-recycle. Implication of STEM-based project into science teaching learning material have been discussed.
Numerical Solution of SEIR Model of The MERS-CoV Disease using Homotopy Analysis Method
Authors: Rangkuti YM. , Firmansyah  , Ginting E. , Landong A. 
Published: March 2021

Abstract
The spread of MERS-Cov disease which was modelled by Susceptible Exposed Infected Recovered (SEIR) model has been solved by a reliable method so-called Homotopy Analysis Method (HAM). The solution using HAM is done by constructing the zero order deformation equation of SEIR model into a high order equation and selecting the convergence control (ℏ). The closeness of HAM and Fourth order Runge Kutta (RK4) solutions and also the existence of residual error showa benchmark of the success of the HAM. The result shows that the minimum errors of the closeness of HAM and fourth order Runge Kutta (RK4) solutions are 10−17 while the minimum residual error of HAM solutions are 10−18. Therefore, HAM has successfully obtained solution of SEIR model approximately. Overall, HAM can be an alternative method for solving more complex models.
Writing a Literature Review: Activities on Research in Mathematics Education to Support Students in Conducting Research
Authors: Haris Denny , Chairunisah  , Armanto Dian 
Published: March 2021

Abstract
Literature review as a crucial requirement in planning a mathematics education research project has received attention in the lecturing of mathematics education research methods in higher education environments. However, the students’ ability to write literature reviews that require skills in managing and analyzing previous relevant research to students’ research requires special attention. This paper aims to represent the significant activities in supporting students’ ability to collect, structure, summarize research finding, and write literature reviews that are relevant to students’ research. Initial data of 15 students’ writing literature review ability was analyzed. Design research comprised the preliminary design, teaching experiment, and retrospective analysis was applied. The outcome of the research presents that students can produce scientific articles through the developed activities of writing literature reviews.
Sentiment Analysis of Community Opinion on Online Store in Indonesia on Twitter using Support Vector Machine Algorithm (SVM)
Authors: Syahputra H 
Published: March 2021

Abstract
Public opinion on the Online Shop service company in Indonesia can be seen through comments sent via tweeter. The purpose of this study is to see the public opinion sentiment towards online stores in Indonesia via Twitter using the Support Vector Machine algorithm. Public opinion and assessment on Twitter can be classified into 3 classes, namely negative, neutral, and positive. The approach used is Multiclass One Vs Rest SVM by using Kernel Sigmoid, Linear, and RBF to classify public tweets about Indonesian Online Shop services, namely Shopee, Tokopedia, Bukalapak, and JDid. The results obtained are the Multiclass (One Vs Rest) Support Vector Machine kernel algorithm which has the best accuracy is the Sigmoid kernel with 82% accuracy on the Shopee online store dataset, 94.7% on the Tokopedia dataset and 75.3% for the Bukalapak dataset, while the Linear kernel Jdid dataset provides better accuracy, namely 78%. Clarification errors can occur due to overfiting, namely the model adjusts the training data very well (accuracy can reach 100%) so that the model cannot generalize well on the testing data.
The Effectiveness of Research Based in Vitro Textbook Application in Contextual Learning on Scientific Attitudes Mastery of Biology Students
Authors: Sugiati Eka , Harahap Fauziyah , Idramsa  
Published: March 2021

Abstract
This research aims to determine the effectiveness of research-based in vitro textbooks in achieving students’ learning outcomes on scientific attitudes mastery. The population of the study was 74 students of undergraduate Biology study program Semester VI academic year 2019/2020 of Universitas Negeri Medan. The Sample was taken by using perposive sampling technique where the classses were grouped in a control class and an experimental class. The experimental class was given treatment by using research-based textbook while the control class used the textbook which was not research-based. The design of the study used Pretest-Posttest Control Group Design. The research instruments used was a questionnaire. To test the hypothesis the reseacher used t-test. The result showed that the mean of posttest from control class was 81,528 on scientific attitude mastery while the posttest mean of experimental class was 91,026. The t-test in the experimental class showed that tcount was 5,413> t table 2,02809 on scientific attitude mastery. Thus the group of students which was given treatment using research-based textbooks had a higher mean score than the group of students without using research-based textbooks.