bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cation substitution and luminescence properties of Eu2+/Ga3+-codoped Na2ZrSi2O7
Authors: Tang Huidong , Li Longzhu , Yang Rong , Chen Yuwei , Seo Hyo Jin 
Published: September 2020

Abstract
Eu2+/Ga3+ co-doped Na2ZrSi2O7 phosphors were prepared via a facile solid-state reaction route. The structural characteristics, photoluminescence spectra, and application performances of Na2-x
Eu
x
Zr1-x
Ga
x
Si2O7 (x= 0, 0.02, 0.04, 0.06, 0.08, 0.10) were investigated. The main motivation of Ga3+ co-doping on Zr4+ is to eliminate the charge imbalance created by the aliovalent substitution of Eu2+ on Na+ sites in the lattices. The results indicated that the Eu2+/Ga3+ co-doped Na2ZrSi2O7 kept a good esseneite-like structure with a triclinic space group of P-1. The phosphor presents a narrow cyan-emitting band centered at 485 nm under near-UV light excitation. The luminescence efficiency of Eu2+ activator was significantly improved through the co-doping of Ga3+ for Zr4+ ions in Na2ZrSi2O7. The maximum luminescence absolute quantum efficiency of 43% was observed in Na2-x
Eu
x
Zr1-x
Ga
x
Si2O7 (x = 0.1) under the excitation of the near-UV light. The phosphor has good thermal stability with an activation energy of 0.31 eV. To realize charge compensation via cation co-substitution could be a practical strategy to improve luminescence in Eu2+-activated phosphors on aliovalent sites.
The temperature induced current transport characteristics in the orthoferrite YbFeO3−

δ

thin film/p-type Si structure
Authors: Polat O , Coskun M , Efeoglu H , Caglar M , Coskun F M , Caglar Y , Turut A 
Published: September 2020

Abstract
The perovskite ytterbium ferrite is a new ferroelectric semiconductor material. We presented the temperature induced current–voltage (I–V) characteristics of the Al/YbFeO3−δ
/p-Si/Al hetero-junction. The orthoferrite YbFeO3−δ
thin films were deposited on a single crystal p-type Si substrate by a radio frequency magnetron sputtering system. The potential barrier height (BH)

and ideality factor n of the heterojunction were obtained by thermionic emission current method based on the recommendations in the literature. The fact that the calculated slopes of I–V curves become temperature independent implying that the field emission current mechanism takes place across the device, which has been explained by the presence of the spatial inhomogeneity of BHs or potential fluctuations. Moreover, a tunneling transmission coefficient value of 26.67 was obtained for the ferroelectric YbFeO3−δ
layer at the Al/p-Si interface.
Electronic properties of Bi2Se3 dopped by 3d transition metal (Mn, Fe, Co, or Ni) ions
Authors: Ptok Andrzej , Kapcia Konrad Jerzy , Ciechan Anna 
Published: September 2020

Abstract
Topological insulators are characterized by the existence of band inversion and the possibility of the realization of surface states. Doping with a magnetic atom, which is a source of the time-reversal symmetry breaking, can lead to realization of novel magneto-electronic properties of the system. In this paper, we study effects of substitution by the transition metal ions (Mn, Fe, Co and Ni) into Bi2Se3 on its electric properties. Using the ab inito supercell technique, we investigate the density of states and the projected band structure. Under such substitution the shift of the Fermi level is observed. We find the existence of nearly dispersionless bands around the Fermi level associated with substituted atoms, especially, in the case of the Co and Ni. Additionally, we discuss the modification of the electron localization function as well as charge and spin redistribution in the system. Our study shows a strong influence of the transition metal-Se bond on local modifications of the physical properties. The results are also discussed in the context of the interplay between energy levels of the magnetic impurities and topological surface states.
Nanoelectrical characterization of individual exosomes secreted by Aβ42-ingested cells using electrostatic force microscopy
Authors: Choi Yeseong , Kim Su-Mi , Heo Youhee , Lee Gyudo , Kang Ji Yoon , Yoon Dae Sung 
Published: September 2020

Abstract
Quantifying the physical properties of individual exosomes containing amyloid-β42 (Aβ42) is crucial for a better understanding of an underpinning mechanism of Alzheimer’s disease expression which is associated with the Aβ42 transfer. Because of the lack of proper tools, however, there have been very few studies on how the amount of Aβ42 affects the physical properties of exosomes. To answer the question, we investigated the physical properties of exosomes secreted by neuroblastoma by probing individual exosomes using electrostatic force microscopy. Interestingly, we observed that when the higher concentration of Aβ42 oligomers was fed to cells, the higher surface charge of the exosomes appeared. This result indicates that the exosomes contain more Aβ42 with the increase in Aβ42 concentration in cell media, implying that they serve as transport vesicles for Aβ42. Our approach could help to better understand how the neuronal exosomes are related to the propagation of neurodegenerative diseases and to seek how to make an early diagnosis of those diseases.
High performance IGZO-based phototransistors by BN/BP interface engineering
Authors: Li Daqing , Nan Haiyan , Mou Penglin , Xu Chunyan , Shao Feng , Gu Xiaofeng , Ostrikov Kostya (Ken) , Xiao Shaoqing 
Published: September 2020

Abstract
Some advances have been achieved in developing heterojunctions consisting of indium-gallium-zinc oxide (a-IGZO) films and two dimensional (2D) van der Waals materials for optoelectronic applications in recent years, however, the improvement of IGZO channel itself via constructing such heterojunctions is rarely reported. Here, we report the huge improvement in photoresponse performances for the IGZO phototransistor devices by introducing boron nitride (BN)/black phosphorus (BP) interface engineering. By creating an appropriate band bending and an efficient photo-generated carrier transfer path between IGZO and BP, the recombination of the photo-generated carriers in the IGZO channel is significantly suppressed. As a result, the corresponding photoresponsivity at a wavelength of 447 nm can be promoted from 0.05 A W−1 to 0.3 A W−1. A corresponding maximum external quantum efficiency of 83.4% was obtained for the BN/BP decorated IGZO phototransistor. The results imply that such interface engineering via 2D materials can be used as a general route to high performance oxide-semiconductor based optoelectronic devices.
Proton beam self-modulation seeded by electron bunch in plasma with density ramp
Authors: Lotov K V , Minakov V A 
Published: September 2020

AbstractSeeded self-modulation in a plasma can transform a long proton beam into a train of micro-bunches that can excite a strong wakefield over long distances, but this needs the plasma to have a certain density profile with a short-scale ramp up. For the parameters of the AWAKE experiment at CERN we numerically study which density profiles are optimal if the self-modulation is seeded by a short electron bunch. With the optimal profiles, it is possible to ‘freeze’ the wakefield at approximately half the wavebreaking level. High-energy electron bunches (160 MeV) are less efficient seeds than low-energy ones (18 MeV), because the wakefield of the former lasts longer than necessary for efficient seeding.
Random polarization distribution of multi-domain model for polycrystalline ferroelectric HfZrO2
Authors: Chen K-T , Liao C-Y , Hsiang K-Y , Chang S-H , Hsieh F-J , Liang H , Chiang S-H , Liu J-H , Li K-S , Chang S T , Lee M H 
Published: September 2020

Abstract
Device dimension scaling down to be comparable to the domain size of polycrystalline ferroelectric HfZrO2 (HZO) is evaluated for subthreshold swing (SS) and drain-induced barrier lowering (DIBL) by numerical simulation. The proposed multi-domain modeling involves polarization random location in HZO and probability with Gaussian distribution, as well as being integrated with the Landau–Khalatnikov equation. A small device with a few domains exhibits steep SS compared with large dimension with many domains. The N-DIBL (negative-DIBL) is also estimated by using this model, and the negative capacitance effect retards the short-channel effects significantly. The trend of the experimental data and simulation results of fin field-effect transistors and planar field-effect transistors is consistent with nano-scale and micro-scale devices, respectively.
Breath acetone change during aerobic exercise is moderated by cardiorespiratory fitness
Authors: Königstein Karsten , Abegg Sebastian , Schorn Andrea N , Weber Ines C , Derron Nina , Krebs Andreas , Gerber Philipp A , Schmidt-Trucksäss Arno , Güntner Andreas T 
Published: September 2020

Abstract
Exhaled breath acetone (BrAce) was investigated during and after submaximal aerobic exercise as a volatile biomarker for metabolic responsiveness in high and lower-fit individuals in a prospective cohort pilot-study. Twenty healthy adults (19–39 years) with different levels of cardiorespiratory fitness (VO2peak), determined by spiroergometry, were recruited. BrAce was repeatedly measured by proton-transfer-reaction time-of-flight mass spectrometry (PTR-TOF-MS) during 40–55 min submaximal cycling exercise and a post-exercise period of 180 min. Activity of ketone and fat metabolism during and after exercise were assessed by indirect calorimetric calculation of fat oxidation rate and by measurement of venous β-hydroxybutyrate (βHB). Maximum BrAce ratios were significantly higher during exercise in the high-fit individuals compared to the lower-fit group (t-test; p= 0.03). Multivariate regression showed 0.4% (95%-CI = −0.2%–0.9%, p= 0.155) higher BrAce change during exercise for every ml kg−1 min−1 higher VO2peak. Differences of BrAce ratios during exercise were similar to fat oxidation rate changes, but without association to respiratory minute volume. Furthermore, the high-fit group showed higher maximum BrAce increase rates (46% h−1) in the late post-exercise phase compared to the lower-fit group (29% h−1). As a result, high-fit young, healthy individuals have a higher increase in BrAce concentrations related to submaximal exercise than lower-fit subjects, indicating a stronger exercise-related activation of fat metabolism.
An Adolescent Porcine Model of Voluntary Alcohol Consumption Exhibits Binge Drinking and Motor Deficits in a Two Bottle Choice Test
Authors: Shin Soo K , Sneed Sydney E , Nennig Sadie E , Cheek Savannah R , Kinder Holly A , Solomon Matthew G , Schank Jesse R , West Franklin D 
Published: September 2020

Abstract

Aims
Alcohol is the most commonly abused substance leading to significant economic and medical burdens. Pigs are an attractive model for studying alcohol abuse disorder due to the comparable alcohol metabolism and consumption behavior, which are in stark contrast to rodent models. This study investigates the usage of a porcine model for voluntary binge drinking (BD) and a detailed analysis of gait changes due to motor function deficits during alcohol intoxication.

Methods
Adolescent pigs were trained to drink increasing concentration (0–8%) of alcohol mixed in a 0.2% saccharin solution for 1 h in a two bottle choice test for 2 weeks. The training period was followed by a 3-week alcohol testing period, where animals were given free access to 8% alcohol in 0.2% saccharin solution and 0.2% saccharin water solution. Blood alcohol levels were tested and gait analysis was performed pre-alcohol consumption, last day of training, and Day 5 of each testing period.

Results
Pigs voluntarily consumed alcohol to intoxication at all timepoints with blood alcohol concentration (BAL) ≥80 mg/dl. Spatiotemporal gait parameters including velocity, cadence, cycle time, swing time, stance time, step time, and stride length were perturbed as a result of intoxication. The stratification of the gait data based on BAL revealed that the gait parameters were affected in a dose-dependent manner.

Conclusion
This novel adolescent BD porcine model with inherent anatomical and physiological similarities to humans display similar consumption and intoxication behavior that is likely to yield results that are translatable to human patients.
Patient-Reported Outcomes Measurement Information System (PROMIS) Assessment of Non-Motor Features in Deep Brain Stimulation Candidates: Relationship to the Beck Depression and Anxiety Inventories
Authors: Loring David W , Block Cady , Staikova Ekaterina , Miocinovic Svjetlana 
Published: September 2020

Abstract

Objective
To compare Patient-Reported Outcomes Measurement Information System (PROMIS) measures of depression and anxiety to the Beck Depression Inventory-II (BDI-II), Beck Anxiety Inventory (BAI), and explore patterns of selected PROMIS measures in patients undergoing evaluation for Deep Brain Stimulation (DBS).

Method
BDI-II, BAI, and seven PROMIS measures were administered to 163 DBS candidates with diagnoses of Parkinson Disease (PD, n = 102), Essential Tremor (ET, n = 45), or Dystonia (n = 16).

Results
Elevated PROMIS Depression using BDI-II Crosswalk equivalents predicted elevated BDI-II with 63% sensitivity and 94% specificity. On other PROMIS measures, 69 patients (42%) reported low Physical Function (T ≤ 40) with Pain Interference being the next most frequent abnormal score (n = 51, 31%). Group differences were present for PROMIS Physical Function, Sleep Disturbance, and Pain.

Conclusions
These preliminary findings provide initial support for PROMIS Depression to assess mood disturbance in DBS candidates, and characterize other PROMIS measures in DBS candidates including group differences reflecting disease specific contribution to Quality of Life.
Sequential organization of birdsong: relationships with individual quality and fitness
Authors: Zsebők Sándor , Herczeg Gábor , Laczi Miklós , Nagy Gergely , Vaskuti Éva , Hargitai Rita , Hegyi Gergely , Herényi Márton , Markó Gábor , Rosivall Balázs , Szász Eszter , Szöllősi Eszter , Török János , Garamszegi László Zsolt 
Published: September 2020

AbstractMany vocalizing animals produce the discrete elements of their acoustic signals in a specific sequential order, but we know little about the biological relevance of this ordering. For that, we must characterize the degree by which individuals differ in how they organize their signals sequentially and relate these differences to variation in quality and fitness. In this study, we fulfilled these tasks in male collared flycatchers (Ficedula albicollis). We characterized the sequential order of syllables with a network analysis approach and studied the consistency of network variables on distinct time scales (within day, between days, and between years), and assessed their relationship with such quality indicators like age, body condition, arrival date, and fitness related proxies like survival to the next year and pairing success. We found that the syllables were associated nonrandomly with one another and both the frequency differences of consecutive syllables and the number of motif types were higher in the original than in randomized syllable sequences. Average degree and small-worldness showed considerable among-individual differences and decreasing repeatability with increasing time scale. Furthermore, we found relationships between male age and average degree among and within individuals. Accordingly, older males produce syllable sequences by using common syllables less often than younger individuals. However, the network variables showed no relationship with fitness-related variables. In conclusion, the sequential organization of birdsong has the potential to encode individual-specific characteristics, which thus could be used as signal in social interactions and thus potentially could be subject to sexual selection.
iCircRBP-DHN: identification of circRNA-RBP interaction sites using deep hierarchical network
Authors: Yang Yuning , Hou Zilong , Ma Zhiqiang , Li Xiangtao , Wong Ka-Chun 
Published: September 2020

Abstract
Circular RNAs (circRNAs) are widely expressed in eukaryotes. The genome-wide interactions between circRNAs and RNA-binding proteins (RBPs) can be probed from cross-linking immunoprecipitation with sequencing data. Therefore, computational methods have been developed for identifying RBP binding sites on circRNAs. Unfortunately, those computational methods often suffer from the low discriminative power of feature representations, numerical instability and poor scalability. To address those limitations, we propose a novel computational method called iCircRBP-DHN using deep hierarchical network for discriminating circRNA-RBP binding sites. The network architecture can be regarded as a deep multi-scale residual network followed by bidirectional gated recurrent units (BiGRUs) with the self-attention mechanism, which can simultaneously extract local and global contextual information. Meanwhile, we propose novel encoding schemes by integrating CircRNA2Vec and the K-tuple nucleotide frequency pattern to represent different degrees of nucleotide dependencies. To validate the effectiveness of our proposed iCircRBP-DHN, we compared its performance with other computational methods on 37 circRNAs datasets and 31 linear RNAs datasets, respectively. The experimental results reveal that iCircRBP-DHN can achieve superior performance over those state-of-the-art algorithms. Moreover, we perform motif analysis on circRNAs bound by those different RBPs, demonstrating that our proposed CircRNA2Vec encoding scheme can be promising. The iCircRBP-DHN method is made available at https://github.com/houzl3416/iCircRBP-DHN.
ADACT: a tool for analysing (dis)similarity among nucleotide and protein sequences using minimal and relative absent words
Authors: Akon Mujtahid , Akon Muntashir , Kabir Mohimenul , Rahman M Saifur , Rahman M Sohel 
Published: September 2020

Abstract

Motivation
Researchers and practitioners use a number of popular sequence comparison tools that use many alignment-based techniques. Due to high time and space complexity and length-related restrictions, researchers often seek alignment-free tools. Recently, some interesting ideas, namely, Minimal Absent Words (MAW) and Relative Absent Words (RAW), have received much interest among the scientific community as distance measures that can give us alignment-free alternatives. This drives us to structure a framework for analysing biological sequences in an alignment-free manner.

Results
In this application note, we present Alignment-free Dissimilarity Analysis & Comparison Tool (ADACT), a simple web-based tool that computes the analogy among sequences using a varied number of indexes through the distance matrix, species relation list and phylogenetic tree. This tool basically combines absent word (MAW or RAW) computation, dissimilarity measures, species relationship and thus brings all required software in one platform for the ease of researchers and practitioners alike in the field of bioinformatics. We have also developed a restful API.

Availability and implementation
ADACT has been hosted at http://research.buet.ac.bd/ADACT/.

Supplementary information
Supplementary data are available at Bioinformatics online.
selectBoost: a general algorithm to enhance the performance of variable selection methods
Authors: Bertrand Frédéric , Aouadi Ismaïl , Jung Nicolas , Carapito Raphael , Vallat Laurent , Bahram Seiamak , Maumy-Bertrand Myriam 
Published: September 2020

AbstractMotivationWith the growth of big data, variable selection has become one of the critical challenges in statistics. Although many methods have been proposed in the literature, their performance in terms of recall (sensitivity) and precision (predictive positive value) is limited in a context where the number of variables by far exceeds the number of observations or in a highly correlated setting.ResultsIn this article, we propose a general algorithm, which improves the precision of any existing variable selection method. This algorithm is based on highly intensive simulations and takes into account the correlation structure of the data. Our algorithm can either produce a confidence index for variable selection or be used in an experimental design planning perspective. We demonstrate the performance of our algorithm on both simulated and real data. We then apply it in two different ways to improve biological network reverse-engineering.Availability and implementationCode is available as the SelectBoost package on the CRAN, https://cran.r-project.org/package=SelectBoost. Some network reverse-engineering functionalities are available in the Patterns CRAN package, https://cran.r-project.org/package=Patterns.Supplementary informationSupplementary data are available at Bioinformatics online.
Jackknife empirical likelihood: small bandwidth, sparse network and high-dimensional asymptotics
Authors: Matsushita Yukitoshi , Otsu Taisuke 
Published: September 2020

Summary
This article aims to shed light on inference problems for statistical models under alternative or nonstandard asymptotic frameworks from the perspective of the jackknife empirical likelihood. Examples include small-bandwidth asymptotics for semiparametric inference and goodness-of-fit testing, sparse-network asymptotics, many-covariates asymptotics for regression models, and many-weak-instruments asymptotics for instrumental variable regression. We first establish Wilks’ theorem for the jackknife empirical likelihood statistic in a general semiparametric inference problem under the conventional asymptotics. We then show that the jackknife empirical likelihood statistic may lose asymptotic pivotalness in the above nonstandard asymptotic frameworks, and argue that this phenomenon can be understood in terms of the emergence of Efron & Stein (1981)’s bias of the jackknife variance estimator at first order. Finally, we propose a modification of the jackknife empirical likelihood to recover asymptotic pivotalness under both conventional and nonstandard asymptotics. Our modification works for all of the above examples and provides a unified framework for investigating nonstandard asymptotic problems.
COVID-19: guaranteed Loans and Zombie Firms
Authors: Zoller-Rydzek Benedikt , Keller Florian 
Published: September 2020

AbstractBased on a survey (7–13 April 2020) we evaluate the reaction of Swiss firms towards the COVID-19 crisis. Firms show little pro-active reactions towards the crisis, but decrease their business activities. The firms in the survey report that the decline in foreign demand is the single most important reason for their deteriorating business situation. Firms that faced a more difficult business situation before the crisis are affected more severely during the crisis. Moreover, we investigate the impact of the Swiss federal loan program (Bundeshilfe) on the business activities. To this end, we develop a stylized theoretical model of financially constrained heterogeneous firms. We find that policy makers face a trade-off between immediate higher unemployment rates and long-term higher public spending. The former arises from a combination of a too strong economic impact of the COVID-19 lockdown (demand drop) and too low levels of loans provided. Nevertheless, providing (too) high levels of loans to firms creates zombie firms that are going to default in the future leading to an increase in public spending. (JEL codes: D22, D25, D84, and G33)