bluuebunny/crossref_metadata_2025 huggingface dataset:
Metalloporphyrin immobilized CeO2: in situ generation of active sites and synergistic promotion of photocatalytic water oxidation
Authors: Meng Jiao , Zhao Yue , Li Haining , Chen Ruiping , Sun Xun , Sun Xuan
Published: January 2021

CoTCPP transfer photoexcited electrons to CeO2 by d–f electron coupling. The in situ generation of catalytically active sites: reduction on CeO2 accompanied with the creation of oxygen vacancies and oxidation on CoTCPP that transforms into CoOOH.
Nanoparticle transformation from ZnO to ZnS through anion exchange with di-tert-butyl disulphide
Authors: Hong Yun-Kun , Park Yoonsu , Kang Hyeri , Son Hyungbin , Ha Don-Hyung
Published: January 2021

The nanoparticle transformation from ZnO to ZnS is demonstrated using di-tert-butyl disulphide (TBDS) as a highly reactive sulphur precursor.
Molecular self-assembly of 1D infinite polyiodide helices in a phenanthrolinium salt
Authors: Poręba Tomasz , Świątkowski Marcin , Kruszyński Rafał
Published: January 2021

Iodine atoms align into a 1D polymeric polyiodide chain, stabilized with the surrounding phenanthrolinium cations.
Bifunctional single-molecular heterojunction enables completely selective CO2-to-CO conversion integrated with oxidative 3D nano-polymerization
Authors: Ma Dong-Dong , Han Shu-Guo , Cao Changsheng , Wei Wenbo , Li Xiaofang , Chen Bo , Wu Xin-Tao , Zhu Qi-Long
Published: January 2021

A bifunctional molecular heterojunction electrocatalyst enables efficient and completely selective CO2 reduction integrated with oxidative 3D nano-polymerization, yielding products of high value at both electrodes with a lower energy input.
Sesamin protects against DSS-induced colitis in mice by inhibiting NF-κB and MAPK signaling pathways
Authors: Chen Shuang , Zhang Chun-Lei , Shen Hai-Qing , Zhou Xiao-Fei , Li Jing-He , Yu Jia-Lin , An Qiang , Fu Ben-Dong , Yi Peng-Fei
Published: January 2021

To investigate the protective effect and mechanisms of sesamin (SES) on dextran sulfate sodium (DSS)-induced experimental colitis in mice.
Wild pink bayberry fruit: the effect of in vitro gastrointestinal digestion on phytochemical profiles, and antioxidant and antiproliferative activities
Authors: Xia Wen , Lin Yanyun , Gong Ersheng , Li Tong , Lian Fengli , Zheng Bisheng , Liu Ruihai
Published: January 2021

In general, pink bayberry cultivar, a vital source of polyphenols, showed strong antiproliferative activity after digestion at the end of the intestinal and colon steps, which can be considered as a dietary supplement.
Digital electrical impedance analysis for single bacterium sensing and antimicrobial susceptibility testing
Authors: Scherer Brian , Surrette Christine , Li Hui , Torab Peter , Kvam Erik , Galligan Craig , Go Steven , Grossmann Greg , Hammond Tyler , Johnson Tammy , St-Pierre Richard , Nelson John R. , Potyrailo Radislav A. , Khire Tejas , Hsieh Kuangwen , Wang Tza-Huei , Wong Pak Kin , Puleo Chris M.
Published: January 2021

We report on a hand-held multiplexed impedance sensor system and show evidence for impedance-based monitoring of the growth of a single bacterium.
A digital microfluidic platform based on a near-infrared light-responsive shape-memory micropillar array
Authors: Ye Wen-Qi , Wei Yun-Yun , Wang Dan-Ni , Yang Chun-Guang , Xu Zhang-Run
Published: January 2021

Droplet manipulation on a near-infrared light-responsive shape-memory micropillar array.
Two routes for sonochemical synthesis of platinum nanoparticles with narrow size distribution
Authors: Hansen Henrik E. , Seland Frode , Sunde Svein , Burheim Odne S. , Pollet Bruno G.
Published: January 2021

The ultrasonic conditions of different sonochemical reactors can be tuned to obtain Pt-nanoparticles of similar sizes. At low ultrasonic frequencies (20 kHz) Ti/V/Al-contaminants were produced due to the probe erosion leading to improved kinetics.
Defect clustering in an Eu-doped NaMgF3 compound and its influence on luminescent properties
Authors: Sousa Afranio , Souza Adelmo , Lima Heveson
Published: January 2021

We combined classical atomistic simulation and crystal field models to describe the origin of defects and their influence on luminescent properties of Eu-doped NaMgF3 in the orthorhombic phase.
Cu-Catalyzedcis-selective ring-opening cross-coupling of an oxabicyclic olefin with an organoboron reagent
Authors: Liu Bowen , Peng Guochun , Zhang Yu , Liu Chunhui , Zhao Jinbo
Published: January 2021

Cu(i)-Catalyzedcis-selective ring-opening of an oxabicyclic olefin with an organoboron reagent is described. DFT studies revealed an alternative boronic ester assisted non-canonical β-oxygen elimination as the rate-determining step.
Synthesis of carboxy-cyclobutane isomers combining an amide bond and self-assembly of coordination polymers in the solid state: controlling the reaction site of [2 + 2] cycloaddition by introducing a substituent group
Authors: Zhu Rong-Rong , Wang Tao , Zhao Lijia , He Liancheng , Gao Feng , Du Lin , Zhao Qi-Hua
Published: January 2021

Combining an amide bond and self-assembly of CPs by solid-state [2 + 2] cycloaddition reactions to synthesize stereoselectively carboxy-cyclobutane isomers.
A controllable thermal-sensitivity separator with an organic–inorganic hybrid interlayer for high-safety lithium-ion batteries
Authors: Chen Hui , Fang Youlong , Liu Xingwei , Jiang Xiaoyu , Zhong Faping , Yang Hanxi , Ai Xinping , Cao Yuliang
Published: January 2021

The PAN/EVA@SiO2/PAN (PESP) separator fabricated by electrospinning approach exhibits a proper shutdown function at approximately 120 °C, which can greatly improve the safety of lithium-ion batteries.
Crystal polymorphism of 8OCB liquid crystal consisting of strongly polar rod-like molecules
Authors: Ghosh Subhadip , Roy Arun
Published: January 2021

The studies on crystal polymorphism of 8OCB liquid crystal showing a metastable PP phase and a heterogeneous CP phase as the stable ground state.
N/Fe/Zn co-doped TiO2 loaded on basalt fiber with enhanced photocatalytic activity for organic pollutant degradation
Authors: Yang Lingxiao , Li Lanmiao , Li Longguo , Liu Chao , Li Jun , Lai Bo , Li Naiwen
Published: January 2021

The photocatalytic activity of N/Fe/Zn_TiO2@BF, synthesized by a combined sol–gel calcination method, showed great improvement for the degradation of RhB. The reaction mechanism of N/Fe/Zn_TiO2@BF for the degradation of RhB was proposed.
Enhanced regeneration of bone defects using sintered porous Ti6Al4V scaffolds incorporated with mesenchymal stem cells and platelet-rich plasma
Authors: Li Ji , Wang Ketao , Bai Xiaowei , Wang Qi , Lv Ningyu , Li Zhongli
Published: January 2021

Porous Ti6AI4V scaffolds incorporated with MSC and PRP are more effective in enhancing the bone regeneration.
Studies on the substrate-dependent photocatalytic properties of Cu2O heterojunctions
Authors: Khasanah Riza Ariyani Nur , Lin Hui-Ching , Ho Hsiang-Yun , Peng Yen-Ping , Lim Tsong-Shin , Hsiao Hsi-Lien , Wang Chang-Ren , Chuang Min-Chieh , Chien Forest Shih-Sen
Published: January 2021

Cu2O/TNA/Ti photoanode showed spectral response outperformed Cu2O/Ti and Cu2O/FTO photocathodes. Cu2O/TNA/Ti showed better spectral response than that of TNA/Ti, ascribed to UV-visible light absorption of Cu2O, not to charge separation enhancement.
Structural, microstructural and magnetic characterization of the β-CoTe nanophase synthesized by a novel mechanochemical method
Authors: Malagutti Marcelo Augusto , de Fátima Ulbrich Kelli , Paes V. Z. C. , Geshev J. , Maduro de Campos Carlos Eduardo
Published: January 2021

This work reports an unprecedented mechanochemistry synthesis of β-CoTe and its systematic characterization through X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), and magnetometry techniques.
Different phosphorylation and farnesylation patterns tune Rnd3–14-3-3 interaction in distinct mechanisms
Authors: Hu Jun , Sun Xue-Meng , Su Jing-Yun , Zhao Yu-Fen , Chen Yong-Xiang
Published: January 2021

Different protein posttranslational modifications (PTMs) patterns affect the binding thermodynamics and kinetics and their molecular mechanism of multivalent protein–protein interaction (PPIs).
Chiral Lewis acid-bonded picolinaldehyde enables enantiodivergent carbonyl catalysis in the Mannich/condensation reaction of glycine ester
Authors: Zhong Xia , Zhong Ziwei , Wu Zhikun , Ye Zhen , Feng Yuxiang , Dong Shunxi , Liu Xiaohua , Peng Qian , Feng Xiaoming
Published: January 2021

The catalytic asymmetric Mannich/condensation of glycine ester with aldimines was achieved by merging chiralN,N′-dioxide/YbIIIcomplex Lewis acid catalysis/carbonyl catalysis under mild condition.
Sewage-free preparation of 2D metal oxides by a rapid freezing soft template method for extraordinarily activating solar-driven humidity VOC combustion
Authors: Yuan Dachao , Ma Luping , Zhao Jianguo , Bai Xianhua , Li Jianchang , Hao Jianjun , Li Yaguang
Published: January 2021

2D Co3O4 can be synthesized without producing sewage, which shows a nearly 100% ambient sunlight irradiated combustion efficiency for formaldehyde, CH4, acetone, CO, as it assisted by spectrally selective coating.
Correction: Utilization of a Pt(ii) di-yne chromophore incorporating a 2,2′-bipyridine-5,5′-diyl spacer as a chelate to synthesize a green and red emitting d–f–d heterotrinuclear complex
Authors: Al-Busaidi Idris Juma , Ilmi Rashid , Dutra José D. L. , Oliveira Willyan F. , Haque Ashanul , Al Rasbi Nawal K. , Marken Frank , Raithby Paul R. , Khan Muhammad S.
Published: January 2021

Correction for ‘Utilization of a Pt(ii) di-yne chromophore incorporating a 2,2′-bipyridine-5,5′-diyl spacer as a chelate to synthesize a green and red emitting d–f–d heterotrinuclear complex’ by Idris Juma Al-Busaidi et al., Dalton Trans., 2021, DOI: 10.1039/d0dt04198j.
Retraction: TMEM88 inhibits fibrosis in renal proximal tubular epithelial cells by suppressing the transforming growth factor-β1/Smad signaling pathway
Authors: Fisher Laura
Published: January 2021

Retraction of ‘TMEM88 inhibits fibrosis in renal proximal tubular epithelial cells by suppressing the transforming growth factor-β1/Smad signaling pathway’ by Huicong Li et al., RSC Adv., 2019, 9, 6928–6934, DOI: 10.1039/C8RA10369K.
Retraction: PKM2 overexpression protects against 6-hydroxydopamine-induced cell injury in the PC12 cell model of Parkinson’s disease via regulation of the brahma-related gene 1/STAT3 pathway
Authors: Fisher Laura
Published: January 2021

Retraction of ‘PKM2 overexpression protects against 6-hydroxydopamine-induced cell injury in the PC12 cell model of Parkinson’s disease via regulation of the brahma-related gene 1/STAT3 pathway’ by Lei Jiang et al., RSC Adv., 2019, 9, 14834–14840, DOI: 10.1039/C9RA01760G.
A mass spectrometry-based glycotope-centric cellular glycomics is the more fruitful way forward to see the forest for the trees
Authors: Khoo Kay-Hooi
Published: January 2021

The nature of protein glycosylation renders cellular glycomics a very challenging task in having to deal with all the disparate glycans carried on membrane glycoproteins. Rapid mapping by mass spectrometry analysis provides only a coarse sketch of the glycomic complexity based primarily on glycosyl compositions, whereby the missing high-resolution structural details require a combination of multi-mode separations and multi-stages of induced fragmentation to gain sufficiently discriminative precision, often at the expenses of throughput and sensitivity. Given the available technology and foreseeable advances in the near future, homing in on resolving the terminal fucosylated, sialylated and/or sulfated structural units, or glycotopes, maybe a more pragmatic and ultimately more rewarding approach to gain insights into myriad biological processes mediated by these terminal coding units carried on important glycoproteins, to be decoded by a host of endogenous glycan-binding proteins and antibodies. A broad overview of recent technical advances and limitations in cellular glycomics is first provided as a backdrop to the propounded glycotope-centric approach based on advanced nanoLC-MS2/MS3 analysis of permethylated glycans. To prioritize analytical focus on the more tangible glycotopes is akin to first identifying the eye-catching and characteristic-defining flowers and fruits of the glyco-forest, to see the forest for the trees. It has the best prospects of attaining the much-needed balance in sensitivity, structural precision and analytical throughput to match advances in other omics.
Integration parameters optimization of low‐voltage multi‐terminal DC system under access of electric vehicles
Authors: Deng Wei , Pei Wei , Zhuang Ying , Kong Li , Li Qiang , Yuan Yubo
Published: January 2021

By integrating the increasing number of electric vehicles (EVs) in the existing multi‐terminal DC system, the new power lines construct can be reduced and the investment in distribution power equipment can be saved. The integration of EVs will affect the power transfer boundary of the system to a certain extent. It is necessary to ensure the normal performance of the system and the power supply for the EVs through the optimal configuration of system integration. The paper proposes the state‐space model of the low‐voltage multi‐terminal DC system, after which the influence of EV integration on the system power transfer boundary and the sensitivity of the power transfer boundary under the change of integration parameters are analysed. Furthermore, an optimization method of EV integration configuration considering the investment cost is proposed, which considers minimizing the system integration cost as the optimization goal and adopts the genetic algorithm for optimization solving. Finally, through the case verification and simulation analysis, the effectiveness of the method is verified, which can minimize the system integration cost and ensure power supply for EVs, without affecting the system power transfer boundary.
Multiwavelength dissection of a massive heavily dust-obscured galaxy and its blue companion at z∼2
Authors: Hamed M. , Ciesla L. , Béthermin M. , Małek K. , Daddi E. , Sargent M. T. , Gobat R.
Published: January 2021

Aims. We study a system of two galaxies, Astarte and Adonis, at z ∼ 2. At this time, the Universe was undergoing the peak of its star formation activity. Astarte is a dusty star-forming galaxy at the massive end of the main sequence (MS), and Adonis is a less massive companion galaxy that is bright in the ultraviolet and has an optical spectroscopic redshift. We investigate whether this ultramassive galaxy is quenching, and whether it has always been on the MS of star-forming galaxies.

Methods. We used the code CIGALE to model the spectral energy distribution. The code relies on the energetic balance between the ultraviolet and the infrared. We derived some of the key physical properties of Astarte and Adonis, mainly their star formation rates (SFRs), stellar masses, and dust luminosities. We inspected the variation of the physical parameters depending on the assumed dust-attenuation law. We also estimated the molecular gas mass of Astarte from its CO emission, using different αCO and transition ratios (r31), and we discuss the implication of the various assumptions on the gas-mass derivation.

Reults. We find that Astarte exhibits a MS-like star formation activity, and Adonis is undergoing a strong starburst phase. The molecular gas mass of Astarte is far lower than the gas fraction of typical star-forming galaxies at z = 2. This low gas content and high SFR result in a depletion time of 0.22 ± 0.07 Gyr, which is slightly shorter than expected for a MS galaxy at this redshift. The CO luminosity relative to the total infrared luminosity suggests a MS-like activity when we assume a galactic conversion factor and a low transition ratio. The SFR of Astarte is on the same order when different attenuation laws are used, unlike its stellar mass, which increases when shallow attenuation laws are used (∼1 × 1011 M⊙ assuming a Calzetti relation, versus ∼4 × 1011 M⊙ assuming a shallow attenuation law). We discuss these properties and suggest that Astarte might be experiencing a recent decrease in star formation activity and is quenching through the MS following a starburst epoch.
Predicted spatial and velocity distributions of ejected companion stars of helium accretion-induced thermonuclear supernovae
Authors: Neunteufel P. , Kruckow M. , Geier S. , Hamers A. S.
Published: January 2021

Context. Thermonuclear supernovae (SNe), a subset of which are the highly important SNe Type Ia, remain one of the more poorly understood phenomena known to modern astrophysics. In recent years, the single degenerate helium (He) donor channel, where a white dwarf star accretes He-rich matter from a hydrogen-depleted companion, has emerged as a promising candidate progenitor scenario for these events. An unresolved question in this scenario is the fate of the companion star, which would be evident as a runaway hot subdwarf O/B stars (He sdO/B) in the aftermath of the SN event.

Aims. Previous studies have shown that the kinematic properties of an ejected companion provide an opportunity to closer examine the properties of an SN progenitor system. However, with the number of observed objects not matching predictions by theory, the viability of this mechanism is called into question. In this study, we first synthesize a population of companion stars ejected by the aforementioned mechanism, taking into account predicted ejection velocities, the inferred population density in the Galactic mass distribution, and subsequent kinematics in the Galactic potential. We then discuss the astrometric properties of this population.

Methods. We present 106 individual ejection trajectories, which were numerically computed with a newly developed, lightweight simulation framework. Initial conditions were randomly generated, but weighted according to the Galactic mass density and ejection velocity data. We then discuss the bulk properties (Galactic distribution and observational parameters) of our sample.

Results. Our synthetic population reflects the Galactic mass distribution. A peak in the density distribution for close objects is expected in the direction of the Galactic centre. Higher mass runaways should outnumber lower mass ones. If the entire considered mass range is realised, the radial velocity distribution should show a peak at 500 km s−1. If only close US 708 analogues are considered, there should be a peak at (∼750 − 850) km s−1. In either case, US 708 should be a member of the high-velocity tail of the distribution.

Conclusions. We show that the puzzling lack of confirmed surviving companion stars of thermonuclear SNe, though possibly an observation-related selection effect, may indicate a selection against high mass donors in the SD He donor channel.
Variation de la microstructure des argiles remaniées sous chargement triaxial et phénomène de dilatance
Authors: Ighil Ameur Lamine , Hattab Mahdia , Gao Qian-Feng
Published: January 2021

Cette recherche expérimentale sur le comportement des argiles vise à tenter de comprendre, et d’identifier, les mécanismes qui s’activent au niveau local en lien avec les déformations volumiques sur chargements triaxiaux. La démarche expérimentale consiste à mettre en évidence l’influence du chemin de chargement sur le comportement micro-macro. Deux différents chemins triaxiaux, l’un conventionnel à σ’3 constante et l’autre purement déviatoire à p’ constant, ont été menés pour atteindre le même niveau de contrainte fixé sur le plan des contraintes. Les essais ont été réalisés sur des échantillons d’argile saturée remaniée reconstituée au laboratoire, en condition normalement consolidée et surconsolidée. L’investigation microstructurale a été menée à deux échelles différentes : au moyen de la Microscopie Electronique à Balayage (MEB), et de la Microtomographie. Les résultats ont mis en évidence l’activation possible de cinq modes d’orientation privilégiée des particules argileuses. Ces modes d’orientation sont fortement dépendants du niveau de contrainte et de l’histoire du chargement. Un développement d’une microfissuration a été observé à l’échelle microscopique et mésoscopique dans les échantillons fortement surconsolidés. L’évolution de cette micro (mais aussi et méso) fissuration semble accompagner clairement le phénomène de la dilatance. Les modes conceptuels d’orientation privilégiée avancés dans ce travail, permettent de mieux comprendre le phénomène de dilatance et de mettre en lumière les mécanismes qui le gouvernent.
An investigation of three mathematical models on the COVID-19 pandemic: the case of Turkey
Authors: Can Engin
Published: January 2021

Mathematical modelling plays a major role in assessing, controlling, and forecasting potential outbreaks. This article consists of implementing mathematical forecasting models by Liang [14], Ma [16], and the curve fitting method with the least squares as a standard approach in regression analysis and compares those calculate results obtained from the Covid-19 outbreak data, which is announced by the Turkish Ministry of Health, between March 10, 2020, and May 15, 2020, in Turkey. For this purpose, we presented an overview of three mathematical models and finally, demonstrated their applications using the Ministry of Health of Turkey’s publicly reported data.
Application of Markov chain in students’ assessment and performance: a case study of School of Mathematical Sciences, one of the public university in Malaysia
Authors: Husna Yahaya Khairun , Hasan Husna
Published: January 2021

The quality education is an essential element in economic, political and social development of any country. Therefore, enrollment forecasting is needed in higher education to assist the universities in the preparation of their educational frameworks including budgeting, provide all necessary facilities and planning the overall short and long term goals. This research study the pattern of students’ assessment and their academic performance in School of Mathematical Sciences, Universiti Sains Malaysia. The target population is all undergraduate enrollment from 2016/2017 until 2018/2019 sessions. An absorbing Markov chain model is applied to study the absorption, retention and repetitive rates of the students by the academic programs and gender. The fundamental matrix is constructed to determine the expected duration of schooling before graduating. The enrollment projection is also estimated to study the probability of the performances of the students in the long run. In summary, this research addresses on the use of Markov chain model to describe the stochastic pattern of the enrollment and assessment of the students.
Prediction region for average claim occurrence rate and average claim size in motor insurance
Authors: Pan Wei Yeing , Soo Huei Ching , Pooi Ah Hin
Published: January 2021

The third-party motor insurance data from Sweden for 1977 described by Andrews and Herzberg in 1985 contain average claim occurrence rate (Pc) , average claim size (Ca) for category of vehicles specified by the kilometres travelled per year (K), geographical zone (Z), no claims bonus (B) and make of car (M). The categorical variables Z and M may first be represented respectively by the vectors (Z1, Z2, … , Z6) and (M1, M2, … , M8) of binary variables. The variable (Pc, Ca) is next modelled to be dependent on X∗ = (K, Z1, Z2, … , Z6, B, M1, M2, … , M8) via a conditional distribution which is derived from an 18-dimensional powernormal distribution. From the conditional distribution, a prediction region for (Pc, Ca) can be obtained to provide useful information on the possible ranges of average claim occurrence rate and average claim size for a given category of vehicles.
The asymmetric responses of stock prices in US market
Authors: Beh Woan Lin , Yew Wen Khang
Published: January 2021

Machine learning and data analytics are so popular in making trading much more efficient by helping the investors to identify opportunities and reduce trading costs. Before applying suitable predictive modelling algorithms, it is crucial for investors or policymaker to understand the nature of the stock data properly. This paper investigates the dependency of macroeconomic factors against the stock markets in the United States using the nonlinear Autoregressive Distributed Lag (NARDL) approach. The analysis considered the Dow Jones Industrial Average Index, NASDAQ Composite Index, and S&P 500 Index. Macroeconomic factors in this country such as consumer price index, export, interest rates, money supply, real effective exchange rates, total reserves, and gold price are considered in this study. In the findings, the NARDL approach shows that the Dow Jones Industrial Average Index and S&P500 Index are having bi-directional positive asymmetric effects to each other in the short run. In short-run, increasing the consumer price index is found to have a negative effect on Dow Jones Industrial Average Index but with a positive effect on S&P500 Index. In conclusion, this study aids investors and other market participants in making a more efficient investment decision.
The new baseline for high dimensional dataset by ranked mutual information features
Authors: Chin Fung Yuen , Goh Yong Kheng
Published: January 2021

Feature selection is a process of selecting a group of relevant features by removing unnecessary features for use in constructing the predictive model. However, high dimensional data increases the difficulty of feature selection due to the curse of dimensionality. From the past research, the performance of the predictive model is always compared with the existing results. When attempting to model a new dataset, the current practice is to benchmark for the dataset obtained by including all the features, including redundant features and noise. Here we propose a new optimal baseline for the dataset by mean of ranked features using a mutual information score. The quality of a dataset depends on the information contained in the dataset, and the more information contains in the dataset, the better the performance of the predictive model. The number of features to achieve this new optimal baseline will be obtained at the same time, and serve as the guideline on the number of features needed in a feature selection method. We will also show some experimental results that the proposed method provides a better baseline with fewer features compared to the existing benchmark using all the features.
Universal portfolio analysis of Malaysia’s stocks for different durations
Authors: Pang Sook Theng , Liew How Hui
Published: January 2021

In this research, four proposed finite order universal portfolios were used to study Malaysia’s stock market comprehensively and the constant rebalanced portfolio (CRP) was used as a benchmark for comparison. The empirical performance of the four universal portfolio strategies was analysed experimentally concerning 95 stocks from different categories in Kuala Lumpur Stock Exchange (KLSE) from 1 January 2000 to 31 December 2015. Combinations of three stocks data from the selected 95 stocks are used for study for short-term (1-year duration), middle-term (4-years and 8-years durations) and long-term (12-years and 16-years durations). The empirical results showed that the performances of the proposed universal strategies are outperform CRP in 1 year and 4 years durations, but did poorly in 8-years, 12-years and 16-years durations. Therefore, these four UP strategies are empirically considered to be good investment strategies in the short-term.
Universal portfolios generated by an inequality involving the Kullback-Leibler and chi-square divergences
Authors: Tan Choon Peng , Lee Yap Jia
Published: January 2021

An inequality involving the Kullback-Leibler and chi-square divergences is used to generate new universal portfolios for investment. The stationary vector of an objective function is determined for the purpose of deciding the next-day portfolio given the current-day portfolio and the current-day price relative vector. The two-parameter portfolio is studied empirically by running the portfolio on selected stock-price data sets from the local stock exchange. It is demonstrated that the wealth of the investor can be increased by using the proposed universal portfolio.
Universal portfolios generated by rational functions
Authors: Kuang Kee Seng , Tan Choon Peng , Goh Yann Ling
Published: January 2021

The f -divergence of Csiszar is defined for a non-negative convex function on the positive axis. A pseudo f -divergence can be defined for a convex function not satisfying the usual requirements. A rational function where both the numerator and the denominator are non-integer polynomials will be used to generate universal portfolios. Five stock-price data sets from the local stock exchange are selected for the empirical study. Empirical results are obtained by running the generated portfolios on these data sets. The empirical results demonstrate that it is possible for the investors to increase their wealth by using the portfolios in investment.
On complete decompositions of dihedral groups
Authors: Chen Huey Voon , Sin Chang Seng
Published: January 2021

Let G be a finite non-abelian group and B1, …, Bt be nonempty subsets of G for integer t ≥ 2. Suppose that B1, …, Bt are pairwise disjoint, then (B1, …, Bt) is called a complete decomposition of G of order t if the subset product Bi1 … Bit = {bi1 … bit | bij ∈ Bij, j = 1,2, …,t} coincides with G, where {Bi1 … Bit} = {B1, …, Bt} and the Bij are all distinct. Let D2n = ‹r,s| rn = s2 = 1, rs =srn-1› be the dihedral group of order 2n for integer n ≥3. In this paper, we shall give the constructions of the complete decompositions of D2n of order t, where 2 ≤ t ≤ n.
Total edge irregularity strength of quadruplet and quintuplet book graphs
Authors: Ratnasari Lucia , Wahyuni Sri , Susanti Yeni , Junia Eksi Palupi Diah
Published: January 2021

LetG= (V, E)be a finite, simple and undirected graph with a vertex setVand an edge setE. An edge irregular totalk-labelling is a functionf : V ᴗE → {1,2,…,k}such that for any two different edgesxyandx’y’inE, their weights are distinct. The weight of edgexyis the sum of label of edgexy, labels of vertexxand of vertexy. The minimumkfor which the graphGadmits an edge irregular totalk-labelling is called the total edge irregularity strength ofG, denoted bytes(G). We have determined the total edge irregularity strength of book graphs, double book graphs and triple book graphs. In this paper, we show the exact value of the total edge irregularity strength of quadruplet book graphs and quintuplet book graphs.
Coefficient problems for classes Hq (φ) and Lq (φ)
Authors: Janteng Aini , Liew Andy Pik Hern
Published: January 2021

A class of analytic functions is denoted by M. Furthermore, S⸦M includes of analytic, normalized and univalent functions. The main -subclasses of S are starlike functions, S and convex functions, S* . Recently, many mathematicians studied about the q-derivative operator. Inspired by the ideas from some previous works, we introduce another two new subclasses of M . The coefficient problems in particular the upper bounds of the Fekete-Szegö (F-S) functional for these subclasses were obtained.
Truncated singular value decomposition in ripped photo recovery
Authors: Lem Kong Hoong
Published: January 2021

Singular value decomposition (SVD) is one of the most useful matrix decompositions in linear algebra. Here, a novel application of SVD in recovering ripped photos was exploited. Recovery was done by applying truncated SVD iteratively. Performance was evaluated using the Frobenius norm. Results from a few experimental photos were decent.
Von der Quantifizierung des Qualitativen
Authors: Singer Dominique
Published: January 2021

Liebe Leserinnen und Leser

mit der Qualität verhält es sich ein bisschen wie mit der
Intelligenz: Letztere definiert sich bekanntlich als das, was der Intelligenztest
misst. Qualität zu quantifizieren – eigentlich ein Oxymoron
–, ist das Ziel sogenannter Indikatoren, anhand derer sich die Struktur, der
Prozess und letztlich das Ergebnis einer Unternehmung bewerten lassen. Ob, wenn
diese Indikatoren erfüllt sind, das Ganze (besonders wenn es sich einer rein
unternehmerischen Betrachtungsweise entzieht) auch wirklich befriedigend
ausfällt, ist freilich ebenso wenig garantiert, wie ein hochrangiger
Intelligenzquotient für eine in jedem Falle einsichtsvolle Handlungsweise
bürgt. Aber immerhin: Ohne die notwendigen, z. B. strukturellen
Voraussetzungen Qualität zu erzielen, dürfte ähnlich
ungewiss sein wie ohne das nötige Einsichtsvermögen bestenfalls
intelligent zu handeln.
Gastkommentar zur Neufassung der S2k-Leitlinie Frühgeborene
an der Grenze der Lebensfähigkeit (AWMF-Register-Nr.
024/019)
Authors: Schleußner Ekkehard
Published: January 2021

Es gibt in der modernen Medizin kaum größere Herausforderungen als in
den Grenzbereichen von Leben und Tod am Lebensanfang wie am Lebensende.
Während die Diskussionen über eine selbstbestimmte Entscheidung am
Lebensende breite Resonanz in der Gesellschaft und den Medien finden, und auch den
Bundestag erreichten, bleiben die grundlegenden ethischen Fragen und Wertekonflikte
am Lebensanfang – nicht nur in der Öffentlichkeit – oft
unreflektiert.
Work satisfaction and risk of burnout for endoscopy staff in Germany: Results of a nationwide survey
Authors: Adarkwah Charles Christian , Labenz Joachim , Birkner Berndt , Beilenhoff UIrike , Pfeifer Ute , Hirsch Oliver
Published: January 2021

Background Healthcare workers are facing ever-increasing challenges. Moreover, in many areas, there is a shortage of skilled personnel, so endoscopy staff are also increasingly exposed to the risk of developing burnout symptoms. Little is known about job satisfaction and burnout prevalence among endoscopy staff. The present study investigates the risk of burnout as well as job satisfaction among skilled personnel in German endoscopy units and practices.

Methods An online survey was conducted among endoscopy staff, a significant proportion of whom are members of Deutsche Gesellschaft für Endoskopiefachberufe e. V. (DEGEA). In addition to general demographic variables, job satisfaction was determined by using the Short Questionnaire for the Assessment of General and Facet-Specific Job Satisfaction (KAFA), and the risk of burnout was determined by using the Maslach Burnout Inventory (MBI-D). Both were associated with structural characteristics.

Results A representative sample took part in the survey (n = 674). The overall level of job satisfaction was high, with a rather elevated risk of burnout, although staff in executive positions performed better overall. Collegiality and mostly flat hierarchies are cited by the majority of those surveyed as positive aspects of their work. Nevertheless, 65 % describe their development opportunities as not performance-oriented, 20 % as virtually non-existent. Over 30 % of those surveyed consider their remuneration to be inadequate.

Conclusion Representative data for the situation in German endoscopy units could be collected. Despite the fact that on average job satisfaction values are high, with a low risk of burnout, especially in comparison with other occupational groups, often mentioned critical aspects regarding the lack of development opportunities and non-performance-related payment should be taken seriously, and measures should be developed to avoid endangering endoscopy care in the long term.
Tandem Alkylation/Michael Addition Reaction of Dithiocarbamic Acids with Alkyl γ-Bromocrotonates: Access to Functionalized 1,3-Thiazolidine-2-thiones
Authors: Ziyaei Halimehjani Azim , Beier Petr , Khalili Foumeshi Maryam , Alaei Ali , Klepetářová Blanka
Published: January 2021

Thiazolidine-2-thiones were prepared via a novel multicomponent reaction of primary amines (amino acids), carbon disulfide, and γ-bromocrotonates. The reaction proceeds via a domino alkylation/intramolecular Michael addition to provide the corresponding thiazolidine-2-thiones in high to excellent yields. By using diamines in this protocol, bis(thiazolidine-2-thiones) derivatives were synthesized. The synthetic utility of the adducts was demonstrated by hydrolysis, amidation, and oxidation reactions.
Transient- and Native-Directing-Group-Enabled Enantioselective C–H Functionalization
Authors: He Chuan , Zu Bing , Guo Yonghong , Ke Jie
Published: January 2021

In recent years, transition-metal-catalyzed enantioselective C–H bond functionalization using chiral transient directing groups (cTDGs) or native directing groups (NDGs) has emerged as a powerful and attractive­ synthetic approach to streamline the synthesis of chiral molecules­. This short review focuses on recent advances on imine-based cTDGs strategies and native amine and carboxylic acid directed strategies for the asymmetric functionalization of various C–H bonds. We have endeavored to highlight the great potential of this methodology and hope that this review will inspire further research in this area.

1 Introduction

2 Transient-Directing-Group-Enabled Enantioselective C–H Functionalization

2.1 Generation of Central Chirality

2.2 Generation of Axial Chirality

2.3 Generation of Planar Chirality

3 Native-Directing-Group-Enabled Enantioselective C–H Functionalization

3.1 Native Amines as Directing Groups

3.2 Native Carboxylic Acids as Directing Groups

4 Conclusions and Outlook
Recurrent Spontaneous Bilateral Subdural Hemorrhage as a Consequence of High-Cervical Spontaneous CSF Leak—Lessons for Neurosurgeons
Authors: Subramaniam Venugopal , Ganapathy Sibhi , Shivananda S. , Nagabhushan K. N. , Murthy Raghu
Published: January 2021

Spontaneous intracranial hypotension (SIH) is rare. It presents as intractable posture headache and is identified by radiological findings. It is confirmed by cerebrospinal fluid (CSF) manometry and myelography, and treatment is carried out with the help of epidural blood patch (EBP) therapy. SIH presenting with spontaneous bilateral recurrent subdural bleeds is uncommon. The cause being a high-spinal CSF leak is even more uncommon! Our patient had recurrent bilateral spontaneous chronic subdural hematomas. Myelographic examination of the spine showed a C1–C2 level leak of CSF. He was taken up for open microsurgery, and the leak was identified and closed with fibrin glue. The patient however deteriorated the next day. An EBP was applied in the lumbar region to cover the myelogram lumbar puncture site. We present a review of literature and an algorithm to detect the elusive CSF leak and effect definitive treatment, either open or EBP, to treat the source of the problem.
Spectroscopic determination of interconversion rates among three nuclear spin isomers of methane in crystalline II
Authors: Sugimoto Takeru , Nasu Hirokazu , Arakawa Ichiro , Yamakawa Koichiro
Published: January 2021

We measured infrared absorption spectra of crystalline II of CH4 and succeeded in detecting a prominent Q(2) peak in the ν3 vibrational region by rapid cooling after annealing as well as previously reported rovibrational and librational-vibrational peaks. The integral intensities of the R(0), R(1), and Q(2) peaks were found to show biexponential dependence on time. This clearly demonstrates the interconversion among the three nuclear-spin isomers occupying low-lying rotational levels. The two relaxation rates obtained by biexponential fitting were (0.48, 2.3), (1.1, 4.1), (2.3, 5.1), and (3.4, 15.3) in units of inverse hour (h−1) at 5.2, 6.0, 6.5, and 7.0 K, respectively.
Quasiclassical calculations of Landau level spectrum for 20.5-nm-wide H gTe quantum well: “extremum loop” model and effects of cubic symmetry
Authors: Gudina S. V. , Bogolubskiy A. S. , Neverov V. N. , Turutkin K. V. , Shelushinina N. G. , Yakunin M. V.
Published: January 2021

Quasiclassical calculations of the effective cyclotron mass and the spectrum of Landau levels have been carried out for carriers of the size-quantized H2 subband with a nonmonotonic dispersion law, which forms a valence band of 20.5-nm-wide HgTe quantum well with an inverted band structure. The model of the so-called “extremum loop”, previously developed by Rashba and Sheka for semiconductors with a wurtzite lattice, has been used for calculations. The results obtained are compared both with the empirical picture and with quantum-mechanical calculations of the Landau level spectrum for the HgTe quantum well in the semimetallic phase.
Localization and interference induced quantum effects at low magnetic fields in InGaAs/GaAs structures
Authors: Savelyev A. P. , Arapov Yu. G. , Gudina S. V. , Neverov V. N. , Podgornykh S. M. , Shelushinina N. G. , Yakunin M. V.
Published: January 2021

The longitudinal ρxx(B, T) and Hall ρxy(B, T) resistances are experimentally investigated in n-InGaAs/GaAs nanostructures with a single and double quantum wells in the magnetic field range B = 0–2.5 T and temperatures T = 1.8–20 K. It is shown that the origin of the temperature-independent point located at ωcτ≅1 on the ρxx(B, T) curves is due to the combined action of the classical cyclotron motion and the quantum interference effects of weak localization and electron-electron interaction. The results obtained indicate that the transition from the dielectric phase to the phase of the quantum Hall effect is a crossover from weak localization (quantum interference effects in a weak magnetic field) to strong localization in quantizing magnetic fields in the quantum Hall effect regime.
Quantum insulator in a semimetal channel on a single type II broken-gap heterointerface in high magnetic fields
Authors: Moiseev K. D. , Golenitskii K. Yu. , Averkiev N. S.
Published: January 2021

The peculiarity of planar quantum magnetotransport in the type II broken-gap p-GaInAsSb/p-InAs heterostructures at high magnetic fields has been investigated. The structure of the hybridized energy spectrum of a two-dimensional semimetal channel at a single type II broken-gap heterointerface was considered in dependence on the composition of the quaternary solid solution. A transition from a conducting state to a dielectric state (quantum insulator) for a 2D-semimetal channel at the heteroboundary was observed in quantizing magnetic fields under the condition of simultaneous filling of the first Landau levels for 2D-electron and interface hole states.
Superconductivity of potassium and rubidium heterofullerides modified with low-melting alloys
Authors: Ezhikov N. S. , Bulychev B. M. , Lunin R. A. , Kulbachinskii V. A.
Published: January 2021

The paper provides experimental data on the synthesis and study of the superconducting properties of potassium and rubidium heterofullerides modified by Wood’s alloy — Sn, Pb, Bi, Cd (hereinafter W) with a melting temperature Tm = 61.5 °C or Y alloy — Bi, Sn, Pb, In, Cd, Tl with Tm = 41.5 °C. The synthesis of heterofullerides was carried out by the interaction of fullerides of the composition K2C60 and Rb2C60, which do not have superconducting properties, with one of the alloys W or Y in an organic solvent — toluene at 100–110 °C. The samples obtained in this case showed superconducting properties with Tc = 8 K for K2YC60 and Rb2WC60 and 16 K for K2WC60.
Discrete orthogonality relations for multi-indexed Laguerre and Jacobi polynomials
Authors: Ho Choon-Lin , Sasaki Ryu
Published: January 2021

The discrete orthogonality relations hold for all the orthogonal polynomials obeying three term recurrence relations. We show that they also hold for multi-indexed Laguerre and Jacobi polynomials, which are new orthogonal polynomials obtained by deforming these classical orthogonal polynomials. The discrete orthogonality relations could be considered as a more encompassing characterization of orthogonal polynomials than the three term recurrence relations. As the multi-indexed orthogonal polynomials start at a positive degree ℓD≥1, the three term recurrence relations are broken. The extra ℓD “lower degree polynomials,” which are necessary for the discrete orthogonality relations, are identified. The corresponding Christoffel numbers are determined. The main results are obtained by the blow-up analysis of the second order differential operators governing the multi-indexed orthogonal polynomials around the zeros of these polynomials at a degree ℓD+N. The discrete orthogonality relations are shown to hold for another group of “new” orthogonal polynomials called Krein–Adler polynomials based on the Hermite, Laguerre, and Jacobi polynomials.
An energy transfer accompanied by phonon absorption in ytterbium-doped yttrium aluminum perovskite for optical refrigeration
Authors: Nakayama Y. , Harada Y. , Kita T.
Published: January 2021

Yttrium aluminum perovskite (YAP) is a host material that can provide a strong emission from a rare-earth dopant and it has a lower phonon energy than yttrium aluminum garnet (YAG). Therefore, YAP is a promising material for optical refrigeration and radiation balanced laser. We measured the photoluminescence (PL) spectra of ytterbium (Yb)-doped YAP and compared them with those of Yb-doped YAG. The estimated ideal laser cooling efficiencies of Yb-doped YAP and Yb-doped YAG were comparable at 300 K. Based on the temperature-dependent anti-Stokes PL, we found that the laser cooling power of Yb-doped YAP at 470 K is 14.3 times higher than that at 200 K. This enhancement at higher temperatures is 3.2 times larger than that observed for Yb-doped YAG. We attributed the higher laser cooling power of Yb-doped YAP to a lower multi-phonon relaxation rate (and/or a higher energy transfer rate) and an antenna effect caused by the energy transfer from Yb ions that are located at the Y-site to Yb ions that are surrounded by an inhomogeneous alloy structure. The calculated small signal gain of (Yb:Y)AP is 3.5 times larger than that of (Yb:Y)AG. The larger small signal gain of (Yb:Y)AP arises from its strong absorbance and small Stark splitting width.
Extended quantitative characterization of solar cell from calibrated voltage-dependent electroluminescence imaging
Authors: Ory Daniel , Paul Nicolas , Lombez Laurent
Published: January 2021

In this paper, we derived a new method to map various optoelectronic parameters of solar cells from voltage-dependent electroluminescence imaging. To get quantitative data, we show how the voltage dependence of electroluminescence mimics a local diode current–voltage behavior, and we propose a way to measure the absolute electroluminescence flux. We therefore introduce a calibration factor generally left unknown in the literature. Example is shown on the Al-BSF silicon solar cell for which we map several parameters: diffusion lengths, dark saturation current, local voltages, and lumped series resistances with good accuracy. Comparison with other electroluminescence imaging methods is also shown. Preliminary knowledge about the sample are the spectral reflection coefficient, average dopant concentration, and back surface recombination. This method can also be derived for other kinds of solar cells by using an appropriate carrier collection model depending on their structure.
Critical field anisotropy in the antiferroelectric switching of PbZrO3 films
Authors: Milesi-Brault Cosme , Godard Nicolas , Girod Stéphanie , Fleming Yves , El Adib Brahime , Valle Nathalie , Glinšek Sebastjan , Defay Emmanuel , Guennou Mael
Published: January 2021

Antiferroelectrics have been recently sparking interest due to their potential use in energy storage and electrocaloric cooling. Their main distinctive feature is antiferroelectric switching, i.e., the possibility to induce a phase transition to a polar phase by an electric field. Here, we investigate the switching behavior of the model antiferroelectric perovskite PbZrO3 using thin films processed by chemical solution deposition in different geometries and orientations. Both out-of-plane and in-plane switching configurations are investigated. The critical field is observed to be highly dependent on the direction of the electric field with respect to the film texture. We show that this behavior is qualitatively consistent with a phase transition to a rhombohedral polar phase. We finally estimate the importance of crystallite orientation and film texturation in the variations observed in the literature.