bluuebunny/crossref_metadata_2025 huggingface dataset:
Keyless Semi-Quantum Point-to-point Communication Protocol with Low Resource Requirements
Authors: Lu Haoye , Barbeau Michel , Nayak Amiya
Published: January 2019

Full quantum capability devices can provide secure communications, but they are challenging to make portable given the current technology. Besides, classical portable devices are unable to construct communication channels resistant to quantum computers. Hence, communication security on portable devices cannot be guaranteed. Semi-Quantum Communication (SQC) attempts to break the quandary by lowering the receiver’s required quantum capability so that secure communications can be implemented on a portable device. However, all SQC protocols have low qubit efficiency and complex hardware implementations. The protocols involving quantum entanglement require linear Entanglement Preservation Time (EPT) and linear quregister size. In this paper, we propose two new keyless SQC protocols that address the aforementioned weaknesses. They are named Economic Keyless Semi-Quantum Point-to-point Communication (EKSQPC) and Rate Estimation EKSQPC (REKSQPC). They achieve theoretically constant minimal EPT and quregister size, regardless of message length. We show that the new protocols, with low overhead, can detect Measure and Replay Attacks (MRA). REKSQDC is tolerant to transmission impairments and environmental perturbations. The protocols are based on a new quantum message transmission operation termed Tele-Fetch. Like QKD, their strength depends on physical principles rather than mathematical complexity.
Associating transcriptional regulation for rapid germination of rapeseed (Brassica napus L.) under low temperature stress through weighted gene co-expression network analysis
Authors: Luo Tao , Xian Mengzhu , Zhang Chen , Zhang Chunni , Hu Liyong , Xu Zhenghua
Published: January 2019

Slow germination speed caused by low temperature stress intensifies the risk posed by adverse environmental factors, contributing to low germination rate and reduced production of rapeseed. The purpose of this study was to understand the transcriptional regulation mechanism for rapid germination of rapeseed. The results showed that seed components and size do not determine the seed germination speed. Different temporal transcriptomic profiles were generated under normal and low temperature conditions in genotypes with fast and slow germination speeds. Using weight gene co-expression network analysis, 37 823 genes were clustered into 15 modules with different expression patterns. There were 10 233 and 9111 differentially expressed genes found to follow persistent tendency of up- and down-regulation, respectively, which provided the conditions necessary for germination. Hub genes in the continuous up-regulation module were associated with phytohormone regulation, signal transduction, the pentose phosphate pathway, and lipolytic metabolism. Hub genes in the continuous down-regulation module were involved in ubiquitin-mediated proteolysis. Through pairwise comparisons, 1551 specific upregulated DEGs were identified for the fast germination speed genotype under low temperature stress. These DEGs were mainly enriched in RNA synthesis and degradation metabolisms, signal transduction, and defense systems. Transcription factors, including WRKY, bZIP, EFR, MYB, B3, DREB, NAC, and ERF, are associated with low temperature stress in the fast germination genotype. The aquaporin NIP5 and late embryogenesis abundant (LEA) protein genes contributed to the water uptake and transport under low temperature stress during seed germination. The ethylene/H2O2-mediated signal pathway plays an important role in cell wall loosening and embryo extension during germination. The ROS-scavenging system, including catalase, aldehyde dehydrogenase, and glutathione S-transferase, was also upregulated to alleviate ROS toxicity in the fast germinating genotype under low temperature stress. These findings should be useful for molecular assisted screening and breeding of fast germination speed genotypes for rapeseed.
Functional and morphological changes of the retinal vessels in Alzheimer’s disease and mild cognitive impairment
Authors: Querques Giuseppe , Borrelli Enrico , Sacconi Riccardo , De Vitis Luigi , Leocani Letizia , Santangelo Roberto , Magnani Giuseppe , Comi Giancarlo , Bandello Francesco
Published: January 2019

Imaging and histopathological studies have demonstrated that structural changes of the retina affect subjects with Alzheimer’s disease (AD) or mild cognitive impairment (MCI). The aim of this study was to quantitatively investigate the retinal vessels in these disorders, using dynamic vessel analyzer (DVA) and optical coherence tomography angiography (OCTA) analysis. Twelve subjects with AD, 12 subjects with MCI, and 32 gender- and age-matched controls were prospectively enrolled. Mean ± SD age was 72.9 ± 7.2 years in the AD group, 76.3 ± 6.9 years in the MCI group, and 71.6 ± 5.9 years in the control group (p = 0.104). In the DVA dynamic analysis, the arterial dilation was decreased in the AD group (0.77 ± 2.06%), in the comparison with the control group (3.53 ± 1.25%, p = 0.002). The reaction amplitude was decreased both in AD (0.21 ± 1.80%, <0.0001) and MCI (2.29 ± 1.81%, p = 0.048) subjects, compared with controls (3.86 ± 1.94%). OCTA variables did not differ among groups. In the Pearson correlation analysis, amyloid β level in the cerebrospinal fluid was directly correlated with the arterial dilation (R = 0.441, p = 0.040) and reaction amplitude (R = 0.580, p = 0.005). This study demonstrate that Alzheimer’s and MCI subjects are characterized by a significant impairment of the retinal neurovascular coupling. This impairment is inversely correlated with the level of amyloid β in the cerebrospinal fluid.
Predicting prolonged sick leave among trauma survivors
Authors: von Oelreich Erik , Eriksson Mikael , Brattström Olof , Discacciati Andrea , Strömmer Lovisa , Oldner Anders , Larsson Emma
Published: January 2019

Many survivors after trauma suffer from long-term morbidity. The aim of this observational cohort study was to develop a prognostic prediction tool for early assessment of full-time sick leave one year after trauma. Potential predictors were assessed combining individuals from a trauma register with national health registers. Two models were developed using logistic regression and stepwise backward elimination. 4458 individuals were included out of which 488 were on sick leave full-time 12 months after the trauma. One comprehensive and one simplified model were developed including nine and seven predictors respectively. Both models showed excellent discrimination (AUC 0.81). The comprehensive model had very good calibration, and the simplified model good calibration. Prediction models can be used to assess post-trauma sick leave using injury-related variables as well as factors not related to the trauma per se. Among included variables, pre-injury sick leave was the single most important predictor for full-time sick leave one year after trauma. These models could facilitate a more efficient use of resources, targeting groups for follow-up interventions to improve outcome. External validation is necessary in order to evaluate generalizability.
Progress of electrospray ionization and rapid evaporative ionization mass spectrometric techniques for the broad-range identification of microorganisms
Authors: Kailasa Suresh Kumar , Koduru Janardhan Reddy , Park Tae Jung , Wu Hui-Fen , Lin Ying-Chi
Published: January 2019

Electrospray ionization and rapid evaporative ionization mass spectrometric techniques have attracted much attention in the identification of microorganisms, and in the diagnosis of bacterial infections from clinical samples.
Rapid and direct mass spectrometric analysis of antibiotics in seawater samples
Authors: He Jing , Zhang Hong , Yu Kai , Qiao Lina , Li Na , Zhang Xiangnan , Zhang Dongmei , Zou Mingqiang , Jiang Jie
Published: January 2019

The SD-DSI is a simple, rapid, and sensitive method for both qualitative and quantitative analysis of antibiotics in seawater samples.
A rhodamine-6G-based “turn-on” fluorescent probe for selective detection of Fe3+ in living cells
Authors: Diao Quanping , Guo Hua , Yang Zhiwei , Luo Weiwei , Li Tiechun , Hou Dongyan
Published: January 2019

A new fluorescent probe R6GES based on rhodamine 6G was designed and synthesized for the detection of Fe3+.
Light-control of the ultra-fast Gp41-1 split intein with preserved stability of a genetically encoded photo-caged amino acid in bacterial cells
Authors: Böcker Jana K. , Dörner Wolfgang , Mootz Henning D.
Published: January 2019

A photo-activatable variant of the fastest protein trans-splicing intein was generated together with suppression of cellular reduction of the ortho-nitrobenzyl protecting group.
Colour and SERS patterning using core–satellite nanoassemblies
Authors: Lee Sungwoon , Kim Minkyu , Yoon Sangwoon
Published: January 2019

Spatial control over the formation of core–satellite nanoassemblies is achieved using UV light.
Do ternary liquid mixtures exhibit negative main Fick diffusion coefficients?
Authors: Kozlova S. , Mialdun A. , Ryzhkov I. , Janzen T. , Vrabec J. , Shevtsova V.
Published: January 2019

Measured main Fick diffusion coefficients are throughout positive. However, they may appear to be negative after transformation to the molar reference frame, if the excess volume is significant and the experimental uncertainties of the cross diffusion coefficients are large.
Colorimetric and ratiometric fluorescence sensing of water based on 9-methyl pyrido[3,4-b]indole-boron trifluoride complex
Authors: Enoki Toshiaki , Ooyama Yousuke
Published: January 2019

9-Methyl pyrido[3,4-b]indole-boron trifluoride complex 9-MP-BF3 was developed as a colorimetric and ratiometric fluorescent sensor for the detection of water from the low- to high-water-content regions in solvents.
Combining ultra-high resolution ion mobility spectrometry with cryogenic IR spectroscopy for the study of biomolecular ions
Authors: Warnke Stephan , Ben Faleh Ahmed , Pellegrinelli Robert P. , Yalovenko Natalia , Rizzo Thomas R.
Published: January 2019

We explore the capability of SLIM-based IMS for isomer selectivity in combination with cryogenic, messenger-tagging IR spectroscopy.
Parahydrogen based NMR hyperpolarisation goes micro: an alveolus for small molecule chemosensing
Authors: Bordonali Lorenzo , Nordin Nurdiana , Fuhrer Erwin , MacKinnon Neil , Korvink Jan G.
Published: January 2019

We implemented continuous-flow SABRE NMR spectroscopy on a chip, unlocking low-volume chemosensing of strongly diluted analytes.
Enhanced charge separation in g-C3N4–BiOI heterostructures for visible light driven photoelectrochemical water splitting
Authors: Alam Kazi M. , Kumar Pawan , Kar Piyush , Thakur Ujwal K. , Zeng Sheng , Cui Kai , Shankar Karthik
Published: January 2019

Heterojunctions of the low bandgap semiconductor bismuth oxyiodide (BiOI) with bulk multilayered graphitic carbon nitride (g-C3N4) and few layered graphitic carbon nitride sheets (g-C3N4-S) are synthesized and investigated as an active photoanode material for sunlight driven water splitting.
2D-MoS2 nanosheets as effective hole transport materials for colloidal PbS quantum dot solar cells
Authors: Tulsani Srikanth Reddy , Rath Arup K. , Late Dattatray J.
Published: January 2019

Herein, we demonstrate for the first time matrix-free deposition of two dimensional (2D) MoS2 nanosheets as an efficient hole transport layer (HTL) for colloidal lead sulfide (PbS) quantum dot (QD) solar cells.
A novel approach for the synthesis of phospholipid bilayer-coated zeolitic imidazolate frameworks: preparation and characterization as a pH-responsive drug delivery system
Authors: Nasihat Sheno Nadia , Farhadi Saeed , Maleki Aziz , Hamidi Mehrdad
Published: January 2019

The first example of enveloping of the ZIF family by PLB as an effective biodegradable/biocompatible/responsive drug delivery system.
NOx removal by selective catalytic reduction with ammonia over hydrotalcite-derived NiTi mixed oxide
Authors: Wu Xu , Wang Ruonan , Du Yali , Li Xiaojian , Meng Hao , Xie Xianmei
Published: January 2019

The speculated mechanism of the SCR reaction over the NiTi-LDO catalyst and the synergetic catalytic effect between Ni and Ti.
Effect of perovskite film morphology on device performance of perovskite light-emitting diodes
Authors: Yu Jae Choul , Park Jong Hyun , Lee Sang Yun , Song Myoung Hoon
Published: January 2019

The device performance and long-term stability of perovskite light-emitting diodes (PeLEDs) can be improved by morphological control of perovskite films such as film modification, interface engineering, and quasi 2D.
Mechanically robust nanocomposites from screen-printable polymer/graphene nanosheet pastes
Authors: Zhang Liqiang , Wang Rui , Wang Jianlei , Wu Lixin , Zhang Xu
Published: January 2019

A screen printing approach utilizing formulated graphene-modified water-based printable pastes is proposed for achieving inexpensive and scalable manufacturing of graphene-reinforced polymer nanocomposites.
Facet-dependent photocatalytic NO conversion pathways predetermined by adsorption activation patterns
Authors: Chen Peng , Sun Yanjuan , Liu Hongjing , Zhou Ying , Jiang Guangming , Lee S. C. , Zhang Yuxin , Dong Fan
Published: January 2019

Facet-dependent photocatalytic NO conversion pathways on Bi2O2CO3 nanoflakes are revealed to be predetermined by adsorption activation patterns.
The formation and detection techniques of oxygen vacancies in titanium oxide-based nanostructures
Authors: Sarkar Ayan , Khan Gobinda Gopal
Published: January 2019

This review highlights different strategies and techniques for introducing and detecting oxygen vacancies in titanium oxide-based nanomaterials.
An N-doped porous carbon network with a multidirectional structure as a highly efficient metal-free catalyst for the oxygen reduction reaction
Authors: Han Hyunsu , Noh Yuseong , Kim Yoongon , Jung Won Suk , Park Seongmin , Kim Won Bae
Published: January 2019

A highly efficient multidirectional N-doped porous carbon network with plenty of graphitic N-species has been explored as cathode catalysts in fuel cells.
Theoretical studies on the purine radical induced purine–purine type intrastrand cross-links
Authors: Wang Shoushan , Ding Jie , Liu Peng , Xie Shilei , Xie Dong , Zhang Min , Cheng Faliang
Published: January 2019

Purine-type radicals can attack their 3′/5′ flanking purine deoxynucleosides forming the purine–purine type DNA intrastrand cross-links.
Porous NaV3(PO4)3/C nanocomposite anode with superior Na-storage performance for sodium-ion batteries
Authors: Wan Xin , Luo Dongxue , Lei Ping , Huang Yunxuan , Xiang Xingde , Sun Molong
Published: January 2019

A porous NaV3(PO4)3/C nanocomposite prepared using a facile solid-phase reaction method showed superior charge/discharge performance as an anode for sodium-ion batteries.
Fe/Zn-modified tricalcium phosphate (TCP) biomaterials: preparation and biological properties
Authors: Xie Lu , Yang Yuanyi , Fu Zhiqiang , Li Yunfei , Shi Jiacheng , Ma Daichuan , Liu Suilin , Luo Daibing
Published: January 2019

Fe/Zn-TCP biomaterials were prepared and their bioactivities to enhance the synthetic bone-repair materials were studied in comparison.
A method of increasing the energy density of layered Ni-rich Li[Ni1−2xCoxMnx]O2 cathodes (x = 0.05, 0.1, 0.2)
Authors: Kim Jae-Hyung , Park Kang-Joon , Kim Suk Jun , Yoon Chong S. , Sun Yang-Kook
Published: January 2019

Lithium-ion batteries with high energy density, long cycle life, and appropriate safety levels are necessary to facilitate the penetration of electrified transportation systems into the automobile market.
Peptide-mediated cationic micelles drug-delivery system applied on a VEGFR3-overexpressed tumor
Authors: Wang Qi Y. , Li Hong M. , Dong Zhi P. , Li Bing X. , Huo Ming , Lu Tao , Wang Yue
Published: January 2019

Copolymers as a kind of drug delivery carrier always lack targeting efficiency.
Understanding phosphoinositides: rare, dynamic, and essential membrane phospholipids
Authors: Dickson Eamonn J. , Hille Bertil
Published: January 2019

Polyphosphoinositides (PPIs) are essential phospholipids located in the cytoplasmic leaflet of eukaryotic cell membranes. Despite contributing only a small fraction to the bulk of cellular phospholipids, they make remarkable contributions to practically all aspects of a cell's life and death. They do so by recruiting cytoplasmic proteins/effectors or by interacting with cytoplasmic domains of membrane proteins at the membrane–cytoplasm interface to organize and mold organelle identity. The present study summarizes aspects of our current understanding concerning the metabolism, manipulation, measurement, and intimate roles these lipids play in regulating membrane homeostasis and vital cell signaling reactions in health and disease.
Glutathione S-transferase gene polymorphisms and risk of nasal or colorectal polyposis
Authors: Zhang Yonglan , Zhang Haichao , Lin Peng , Zhang Guimin
Published: January 2019

We observed inconsistent conclusions regarding the genetic role of glutathione S-transferase gene polymorphisms, including glutathione S-transferase M1 (GSTM1), glutathione S-transferase T1 (GSTT1) present/null, and glutathione S-transferase pi (GSTP1) Ile105Val polymorphisms, in the susceptibility to nasal or colorectal polyposis (NP or CP). Thus, we aimed to perform a meta-analysis to comprehensively evaluate this association by applying Stata/SE software. After the heterogeneity assumption, Mantel–Haenszel statistics were used to obtain the odds ratio (OR), 95% confidence interval (95% CI) and P-value of the association test (PA). We obtained a total of 235 articles by searching online databases. After screening, ten eligible case–control studies were finally enrolled in our meta-analysis. For the meta-analysis of the GSTT1 gene under present versus null, we observed a decreased risk of NP [OR = 0.65; PA=0.018], but not CP. In addition, we did not detect any evident association between the GSTM1 present/null polymorphism and NP or CP risk. For the meta-analysis of the GSTP1 Ile105Val polymorphism, compared with controls, an increased risk of NP cases was detected under the models of Val versus Ile (OR = 1.36; PA=0.027), Ile/Val versus Ile/Ile (OR = 1.70; PA=0.011) and Ile/Val+Val/Val versus Ile/Ile (OR = 1.65; PA=0.010). In conclusion, the null genotype of the GSTT1 polymorphism may be linked to an increased susceptibility to NP, whereas the Ile/Val genotype of the GSTP1 Ile105Val polymorphism may be associated with a decreased risk of NP.
Neutral endopeptidase inhibitors blunt kidney fibrosis by reducing myofibroblast formation
Authors: Bijkerk Roel , Aleksinskaya Marina A. , Duijs Jacques M.G.J. , Veth Jennifer , Husen Bettina , Reiche Dania , Prehn Cornelia , Adamski Jerzy , Rabelink Ton J. , De Mey Jo G.R. , van Zonneveld Anton Jan
Published: January 2019

Kidney fibrosis is the common pathophysiological mechanism in end-stage renal disease characterized by excessive accumulation of myofibroblast-derived extracellular matrix. Natriuretic peptides have been demonstrated to have cyclic guanosine monophosphate (cGMP)-dependent anti-fibrotic properties likely due to interference with pro-fibrotic tissue growth factor β (TGF-β) signaling. However, in vivo, natriuretic peptides are rapidly degraded by neutral endopeptidases (NEP). In a unilateral ureteral obstruction (UUO) mouse model for kidney fibrosis we assessed the anti-fibrotic effects of SOL1, an orally active compound that inhibits NEP and endothelin-converting enzyme (ECE). Mice (n=10 per group) subjected to UUO were treated for 1 week with either solvent, NEP-/ECE-inhibitor SOL1 (two doses), reference NEP-inhibitor candoxatril or the angiotensin II receptor type 1 (AT1)-antagonist losartan. While NEP-inhibitors had no significant effect on blood pressure, they did increase urinary cGMP levels as well as endothelin-1 (ET-1) levels. Immunohistochemical staining revealed a marked decrease in renal collagen (∼55% reduction, P<0.05) and α-smooth muscle actin (α-SMA; ∼40% reduction, P<0.05). Moreover, the number of α-SMA positive cells in the kidneys of SOL1-treated groups inversely correlated with cGMP levels consistent with a NEP-dependent anti-fibrotic effect. To dissect the molecular mechanisms associated with the anti-fibrotic effects of NEP inhibition, we performed a ‘deep serial analysis of gene expression (Deep SAGE)’ transcriptome and targeted metabolomics analysis of total kidneys of all treatment groups. Pathway analyses linked increased cGMP and ET-1 levels with decreased nuclear receptor signaling (peroxisome proliferator-activated receptor [PPAR] and liver X receptor/retinoid X receptor [LXR/RXR] signaling) and actin cytoskeleton organization. Taken together, although our transcriptome and metabolome data indicate metabolic dysregulation, our data support the therapeutic potential of NEP inhibition in the treatment of kidney fibrosis via cGMP elevation and reduced myofibroblast formation.
A Comment on Test Validation: The Importance of the Clinical Perspective
Authors: Daub Olivia , Skarakis-Doyle Elizabeth , Bagatto Marlene P. , Johnson Andrew M. , Cardy Janis Oram
Published: January 2019

Purpose

The misuse of standardized assessments has been a long-standing concern in speech-language pathology and traditionally viewed as an issue of clinician competency and training. The purpose of this article is to consider the contribution of communication breakdowns between test developers and the end users to this issue.

Method

We considered the misuse of standardized assessments through the lens of the 2-communities theory, in which standardized tests are viewed as a product developed in 1 community (researchers/test developers) to be used by another community (frontline clinicians). Under this view, optimal test development involves a conversation to which both parties bring unique expertise and perspectives.

Results

Consideration of the interpretations that standardized tests are typically validated to support revealed a mismatch between these and the interpretations and decisions that speech-language pathologists typically need to make. Test development using classical test theory, which underpins many of the tests in our field, contributes to this mismatch. Application of item response theory could better equip clinicians with the psychometric evidence to support the interpretations they desire but is not commonly found in the standardized tests used by speech-language pathologists.

Conclusions

Advocacy and insistence on the consideration of clinical perspectives and decision making in the test validation process is a necessary part of our role. In improving the nature of the statistical evidence reported in standardized assessments, we can ensure these tools are appropriate to fulfill our professional obligations in a clinically feasible way.
The Subjective Experience of Inner Speech in Aphasia Is a Meaningful Reflection of Lexical Retrieval
Authors: Fama Mackenzie E. , Snider Sarah F. , Henderson Mary P. , Hayward William , Friedman Rhonda B. , Turkeltaub Peter E.
Published: January 2019

Purpose

Individuals with aphasia often report that they feel able to say words in their heads, regardless of speech output ability. Here, we examine whether these subjective reports of successful “inner speech” (IS) are meaningful and test the hypothesis that they reflect lexical retrieval.

Method

Participants were 53 individuals with chronic aphasia. During silent picture naming, participants reported whether or not they could say the name of each item inside their heads. Using the same items, they also completed 3 picture-based tasks that required phonological retrieval and 3 matched auditory tasks that did not. We compared participants' performance on these tasks for items they reported being able to say internally versus those they reported being unable to say internally. Then, we examined the relationship of psycholinguistic word features to self-reported IS and spoken naming accuracy.

Results

Twenty-six participants reported successful IS on nearly all items, so they could not be included in the item-level analyses. These individuals performed correspondingly better than the remaining participants on tasks requiring phonological retrieval, but not on most other language measures. In the remaining group (
n
= 27), IS reports related item-wise to performance on tasks requiring phonological retrieval, but not to matched control tasks. Additionally, IS reports were related to 3 word characteristics associated with lexical retrieval, but not to articulatory complexity; spoken naming accuracy related to all 4 word characteristics. Six participants demonstrated evidence of unreliable IS reporting; compared with the group, they also detected fewer errors in their spoken responses and showed more severe language impairments overall.

Conclusions

Self-reported IS is meaningful in many individuals with aphasia and reflects lexical phonological retrieval. These findings have potential implications for treatment planning in aphasia and for our understanding of IS in the general population.
Massive star evolution: rotation, winds, and overshooting vectors in the mass-luminosity plane
Authors: Higgins Erin R. , Vink Jorick S.
Published: January 2019

Context. Massive star evolution is dominated by various physical effects, including mass loss, overshooting, and rotation, but the prescriptions of their effects are poorly constrained and even affect our understanding of the main sequence.

Aims. We aim to constrain massive star evolution models using the unique test-bed eclipsing binary HD 166734 with new grids of MESA stellar evolution models, adopting calibrated prescriptions of overshooting, mass loss, and rotation.

Methods. We introduce a novel tool, called the mass-luminosity plane or M−L plane, as an equivalent to the traditional HR diagram, utilising it to reproduce the test-bed binary HD 166734 with newly calibrated MESA stellar evolution models for single stars.

Results. We can only reproduce the Galactic binary system with an enhanced amount of core overshooting (αov = 0.5), mass loss, and rotational mixing. We can utilise the gradient in the M−L plane to constrain the amount of mass loss to 0.5–1.5 times the standard prescription test-bed, and we can exclude extreme reduction or multiplication factors. The extent of the vectors in the M−L plane leads us to conclude that the amount of core overshooting is larger than is normally adopted in contemporary massive star evolution models. We furthermore conclude that rotational mixing is mandatory to obtain the correct nitrogen abundance ratios between the primary and secondary components (3:1) in our test-bed binary system.

Conclusions. Our calibrated grid of models, alongside our new M−L plane approach, present the possibility of a widened main sequence due to an increased demand for core overshooting. The increased amount of core overshooting is not only needed to explain the extended main sequence, but the enhanced overshooting is also needed to explain the location of the upper-luminosity limit of the red supergiants. Finally, the increased amount of core overshooting has – via the compactness parameter – implications for supernova explodability.
A progenitor candidate for the type II-P supernova SN 2018aoq in NGC 4151
Authors: O’Neill D. , Kotak R. , Fraser M. , Sim S. A. , Benetti S. , Smartt S. J. , Mattila S. , Ashall C. , Callis E. , Elias-Rosa N. , Gromadzki M. , Prentice S. J.
Published: January 2019

We present our findings based on pre- and post-explosion data of the type II-Plateau SN 2018aoq that exploded in NGC 4151. As distance estimates to NGC 4151 vary by an order of magnitude, we utilised the well-known correlation between ejecta velocity and plateau brightness, i.e. the standard candle method, to obtain a distance of 18.2 ± 1.2 Mpc, which is in very good agreement with measurements based on geometric methods. The above distance implies a mid-plateau absolute magnitude of MV50 = − 15.76 ± 0.14 suggesting that it is of intermediate brightness when compared to IIP SNe such as SN 2005cs at the faint end, and more typical events such as SN 1999em. This is further supported by relatively low expansion velocities (Fe IIλ5169 ∼ 3000 km s−1 at +42 d). Using archival HST/WFC3 imaging data, we find a point source coincident with the supernova position in the F350LP, F555W, F814W, and F160W filters. This source shows no significant variability over the ∼2 month time span of the data. From fits to the spectral energy distribution of the candidate progenitor, we find log(L/L⊙) ∼ 4.7 and Teff ∼ 3.5 kK, implying an M-type red supergiant progenitor. From comparisons to single and binary star models, we find that both favour the explosion of a star with a zero-age main sequence mass of ∼10 M⊙.
An XMM-Newton look at the strongly variable radio-weak BL Lac Fermi J1544–0639
Authors: Ursini F. , Bassani L. , Panessa F. , Pian E. , Bruni G. , Bazzano A. , Masetti N. , Sokolovsky K. , Ubertini P.
Published: January 2019

Context. Fermi J1544–0639/ASASSN-17gs/AT2017egv was identified as a gamma-ray/optical transient on May 15, 2017. Subsequent multiwavelength observations suggest that this source may belong to the new class of radio-weak BL Lacs.

Aims. We studied the X-ray spectral properties and short-term variability of Fermi J1544–0639 to constrain the X-ray continuum emission mechanism of this peculiar source.

Methods. We present the analysis of an XMM-Newton observation, 56 ks in length, performed on February 21, 2018.

Results. The source exhibits strong X-ray variability, both in flux and spectral shape, on timescales of ∼10 ks, with a harder-when-brighter behaviour typical of BL Lacs. The X-ray spectrum is nicely described by a variable broken power law, with a break energy of around 2.7 keV consistent with radiative cooling due to Comptonization of broad-line region photons. We find evidence for a “soft excess”, nicely described by a blackbody with a temperature of ∼0.2 keV, consistent with being produced by bulk Comptonization along the jet.
Calculation of the interfacial tension of the graphene-water interaction by molecular simulations
Authors: Dreher Thibaud , Lemarchand Claire , Pineau Nicolas , Bourasseau Emeric , Ghoufi Aziz , Malfreyt Patrice
Published: January 2019

We report the calculation of the solid-liquid interface tension of the graphene-water interaction by using molecular simulations. Local profiles of the interfacial tension are given through the mechanical and thermodynamic definitions. The dependence of the interfacial tension on the graphene area is investigated by applying both reaction field and Ewald summation techniques. The structure of the interfacial region close to the graphene sheet is analyzed through the profiles of the density and hydrogen bond number and the orientation of the water molecules. We complete this study by plotting the profiles of the components of the pressure tensor calculated by the Ewald summation and reaction field methods. We also investigate the case of a reaction field version consisting in applying a damped shifted force in the case of the calculation of the pressure components.
First principles study of hBN-AlN short-period superlattice heterostructures
Authors: Spataru Catalin D. , Crawford Mary H. , Allerman Andrew A.
Published: January 2019

We report a theoretical study of the structural, electronic, and optical properties of hBN-AlN superlattice (SL) heterostructures using a first-principles approach based on standard and hybrid density functional theory. We consider a short-period (L < 10 nm) SL and find that its properties depend strongly on the AlN layer thickness LAlN. For LAlN≲1 nm, AlN stabilizes into the hexagonal phase and the SL displays insulating behavior with type II interface band alignment and optical gaps as small as 5.2 eV. The wurtzite phase is formed for thicker AlN layers. In these cases, built-in electric fields lead to the formation of polarization compensating charges as well as two-dimensional conductive behavior for electronic transport along interfaces. We also find defect-like states localized at interfaces which are optically active in the visible range.
A compact solid-state high voltage pulse generator
Authors: Gao Jingming , Li Song , Shi Chengyu , Cui Yancheng , Yang Hanwu
Published: January 2019

In this paper, a compact solid-state high voltage pulse generator, composed of a pulse transformer and a magnetic pulse compressor, is investigated numerically and experimentally. The generator can achieve pulses with a peak voltage over several tens of kilovolts and a rise-time in the microsecond level, which can be widely used in plasma physics research, high power microwave generation, and material treatment. Specifically, PSpice software is used to analyze the performance of the generator. Then, the generator was constructed in our laboratory. The experimental results illustrate that when the charging voltage of the generator was changing from 10 kV to 14 kV, typical pulses with a peak voltage ranging from 67 kV to 95 kV and rise-time between 10 µs and 12 µs were obtained on a dummy load. The generator can continually work over 10 min with a repetitive rate of 20 Hz, and until now, it has been successfully achieving over 1 × 106 high voltage pulses. Experiments show reasonable agreement with numerical analysis.
Subtlety of TiO2 phase stability: Reliability of the density functional theory predictions and persistence of the self-interaction error
Authors: Zhang Yubo , Furness James W. , Xiao Bing , Sun Jianwei
Published: January 2019

TiO2 is an important material with broad applications that can exist in different phases with dramatically different properties. Theoretical prediction of their polymorph energetics is therefore critical for the material design and for identifying thermodynamically accessible structures. Determining TiO2 relative phase stabilities remains challenging for first-principles methods, and density functional theory is the only approach available for studying phase stabilities at finite temperatures with acceptable computational efficiency. Here, we show that density functional theory using the recently developed efficient strongly constrained and appropriately normed (SCAN) [Sun et al., Phys. Rev. Lett. 115, 036402 (2015)] exchange-correlation functional for the first time predicts the phase stability in qualitative agreement with the experimental results at realistic conditions. Further analysis shows that the self-interaction error intrinsic in the density functional persists in the stability prediction. By correcting the self-interaction error through an empirical approach, SCAN predicts the relative stability as well as defect properties in excellent agreement with the experimental results.
Model evaluations of surface modification by energetic incident carbon atoms on graphene coated copper electrodes
Authors: Qiu X. , Mankowski J. , Dickens J. C. , Neuber A. A. , Joshi R. P.
Published: January 2019

Thin nanoscale coating of metal electrodes by graphene promises to be a useful approach for suppressing the secondary electron yield and potential multipactor. Recent calculations showed reductions by as much as 50% for graphene over copper electrodes for energies below 125 eV, with results in good agreement with experimental data. Here, the resistance to possible degradation of this structure, in response to incoming atomic projectiles, is gauged based on molecular dynamics simulations. Our results for surface irradiation by carbon atoms (as an example) on nanoscale graphene coatings indicate a defect threshold of about 35 eV, lower surface damage for thicker layers, negligible sputtering, and defects less than 6 Å in dimension for energies up to 300 eV. The electrode structure is shown to be robust with better resistance to damage than metal alone.
Detection of heat flux at single-atom scale in a liquid-solid interfacial region based on classical molecular dynamics
Authors: Fujiwara K. , Shibahara M.
Published: January 2019

In this study, we examine heat flux at the single-atom scale in a liquid-solid interfacial region by calculating local quantities based on classical molecular dynamics. The heat flux was calculated over a subatomic area defined on the liquid-solid interfacial region, and a two-dimensional map of the local heat flux at the liquid-solid interface was obtained. The results clearly showed directional heat flux at the single-atom scale between the liquid and solid phases; the spatial heat conduction was not uniform along a temperature gradient in the immediate vicinity of the solid surface, which suggests that the interfacial thermal resistance can be interpreted more precisely based on the local quantity of the heat flux. The methodology and results given in this study should prove useful to more precisely interpret and control heat transfer and thermal resistance at interfaces.
Enhancing the adhesion and tribological performance of Si-DLC film on NBR by Ar plasma pretreatment under a high bias
Authors: Qiang Li , Bai Changning , Liang Aimin , Zhang Junyan
Published: January 2019

Silicon-containing diamond-like carbon (Si-DLC) films were successfully deposited on nitrile-butadiene rubber (NBR) via magnetron sputtering Si target in Ar and CH4 mixture atmosphere. The influence of Ar plasma pretreatment bias on the adhesion and tribological properties of the Si-DLC coated NBR were investigated systematically. The results indicated that the surface roughness of NBR substrate decreased monotonously with the increase of bias. Compared with the virgin NBR, the surface topography did not change significantly under a low bias, but a shallow layer and considerable chain scission could be observed by SEM and FTIR analysis under a high bias. As a consequence, the excellent adhesion could be obtained by Ar plasma pretreatment under a high bias (>-500 V), while the adhesion of the samples pretreated by a low bias (≤-500 V) were even worse than that of untreated samples. Furthermore, the samples pretreated at a relatively high bias of -1000 V exhibited the lowest and stable friction coefficient of 0.25 and outstanding wear resistance, while the tribological performance of the samples pretreated with a low bias (≤-500V) were even worse than that of untreated ones. The research results of this work are of great surface engineering significance for the design and fabrication of hard films with a high adhesion and excellent tribological performance on rubber substrates.
Electromigration in the dissipative state of high-temperature superconducting bridges
Authors: Baumans X. D. A. , Fernández-Rodríguez A. , Mestres N. , Collienne S. , Van de Vondel J. , Palau A. , Silhanek A. V.
Published: January 2019

The current stimulated atomic diffusion in YBa2Cu3O7–δ superconducting bridges is investigated. A superconductor to insulator transition can be induced by the current controlled electromigration process, whereas the partial recovery of the superconducting state can be achieved by inverting the polarity of the bias. Interestingly, the temperature dependence of the current density JEM(T), above which atomic migration takes place, intersects the critical current density Jc(T) at certain temperature T*. Therefore, for T < T*, the current-induced dissipative state cannot be accessed without leading to irreversible modifications of the material properties. This phenomenon could also lead to the local deterioration of high critical temperature superconducting films abruptly penetrated by thermomagnetic instabilities.
Intermittent plasticity in individual grains: A study using high energy x-ray diffraction
Authors: Chatterjee K. , Beaudoin A. J. , Pagan D. C. , Shade P. A. , Philipp H. T. , Tate M. W. , Gruner S. M. , Kenesei P. , Park J.-S.
Published: January 2019

Long-standing evidence suggests that plasticity in metals may proceed in an intermittent fashion. While the documentation of intermittency in plastically deforming materials has been achieved in several experimental settings, efforts to draw connections from dislocation motion and structure development to stress relaxation have been limited, especially in the bulk of deforming polycrystals. This work uses high energy x-ray diffraction measurements to build these links by characterizing plastic deformation events inside individual deforming grains in both the titanium alloy, Ti-7Al, and the magnesium alloy, AZ31. This analysis is performed by combining macroscopic stress relaxation data, complete grain stress states found using far-field high energy diffraction microscopy, and rapid x-ray diffraction spot measurements made using a Mixed-Mode Pixel Array Detector. Changes in the dislocation content within the deforming grains are monitored using the evolution of the full 3-D shapes of the diffraction spot intensity distributions in reciprocal space. The results for the Ti-7Al alloy show the presence of large stress fluctuations in contrast to AZ31, which shows a lesser degree of intermittent plastic flow.
Enhancement of valley polarization in graphene with an irradiating charged particle
Authors: Zhang Ya , Jiang Wei
Published: January 2019

We use a two-dimensional two-component nonlinear hydrodynamic method to study valley-dependent plasmons in bounded strained graphene in the presence of an irradiating proton, realizing electrostatic control of the valley-dependent plasmons in actual space. We use flux-corrected transport to solve the nonlinear hydrodynamic equations numerically and self-consistently. Our results answer the important question of whether full valley polarization can be obtained in a specific valley at the boundary or inside the graphene sheet in the presence of the injected proton. The electrons experience collective excitations due to the proton interaction and the strain-induced pseudomagnetic field. The electron density fluctuation can be much larger than the equilibrium electron density, leading to a strong nonlinear effect and thus full valley polarization. This demonstrates the nature of the nonlinear response of electrons in graphene to strong interactions, a response that originates from the strong nonperturbative interaction between the irradiating proton and the electrons. Thus, our method opens up the possibility of investigating the nonlinear behavior of valley-dependent plasmons in strong modulations. The effects of the proton on the valley polarization are examined. There is K-polarization inside the surface behind the proton, whereas there is K′-polarization at the edge which decays away from the edge, thereby switching the valley polarization. This work establishes a link between actual-space valley-dependent plasmons in graphene and the irradiating proton and provides an alternative way to realize full valley polarization with tunable polarity. Compared to the case with no proton, the valley polarization is enhanced considerably in the presence of a proton.
Micro-scale droplet deposition for micro-object self-alignment release based on water condensation
Authors: Fan Zenghua , Rong Weibin , Tian Yebing , Wei Xiuting , Gao Jun
Published: January 2019

We report experimental evidence for a controllable capillary micromanipulation method that enables micro-scale droplets to be deposited flexibly for self-alignment release. By controlling the water condensation on a probe-tip, the volume of the droplet is varied dynamically, which helps to establish an appropriate initial droplet for liquid deposition on the desired substrate. The droplet deposition and self-alignment processes were experimentally characterized to verify the performance potential of the proposed integrated method, using a customized motion platform equipped with viewing microscopes. The results demonstrated that the contact angle and the droplet volume on the probe-tip varied during water condensation control. Accordingly, the deposited droplets could be regulated by changing the stretching speed. A 100% success rate in 36 trials was achieved in releasing polystyrene microspheres with diameters of 100 μm and 200 μm, and the released microspheres with offset moved to the desired target destinations under temperature control. The results provide a promising solution for self-alignment management of the assembly of micro-parts.
Scaling with a fractional power: Overcoming the shortage of scaled-particle variables for the hard-disk fluid
Authors: Hansen-Goos Hendrik
Published: January 2019

Within scaled-particle theory, we construct an equation of state (EOS) for hard-disk mixtures by making use of an additional scaled-particle variable which weighs the densities of the different components by its radii to the power χ. This allows us to simultaneously respect exact results pertaining to the cases of a large particle or a point particle being added to the mixture. In the limit χ → 2, the mixture EOS of Santos et al. [Mol. Phys. 96, 1 (1999)] is recovered, while the limit χ → 0 yields the accurate expression for the interfacial free energy of Martin et al. [J. Chem. Phys. 149, 084701 (2018)]. From the low-density limit of the EOS, the value χ ≈ 0.8 is extracted, which is shown to yield a mixture EOS that is significantly more accurate than the expressions due to Santos et al. and Martin et al. In particular, the systematic deviation inherent to these prior results is remedied.
Process development for stabilization of vacuum arc plasma generation from a TiB2 cathode
Authors: Zhirkov Igor , Polcik Peter , Kolozsvári Szilard , Rosen Johanna
Published: January 2019

Herein, we present stable and reproducible arc plasma generation from a TiB2 cathode. The process development contains three complimentary features: Use of a Mo cylinder around the TiB2 cathode improves arc ignition and stabilizes the process by keeping the arc spot at the cathode surface. The evolution of the cathode surface during erosion and the process stability is further improved by addition of 1wt% carbon in the cathode, with no resulting change in plasma characteristics (ion energy, ion charge states, macroparticles). Finally, an increased plasma density through use of a separate anode provides the last key point, which together with the other two contributes to highly controlled plasma generation from TiB2 using DC vacuum arc, and complete utilization of the cathode material. The combined results provide a novel and efficient route for synthesis of metal borides.
Measuring the difficulty of text translation
Authors: Liu Yanmei , Zheng Binghan , Zhou Hao
Published: January 2019

This paper explores the impact of text complexity on translators’ subjective perception of translation difficulty and on their cognitive load. Twenty-six MA translation students from a UK university were asked to translate three English texts with different complexity into Chinese. Their eye movements were recorded by an eye-tracker, and their cognitive load was self-assessed with a Likert scale before translation and NASA-TLX scales after translation. The results show that: (i) the intrinsic complexity measured by readability, word frequency and non-literalness was in line with the results received from informants’ subjective assessment of translation difficulty; (ii) moderate and positive correlations existed between most items in the self-assessments and the indicator (fixation and saccade durations) obtained by the eye-tracking measurements; and (iii) the informants’ cognitive load as indicated by fixation and saccade durations (but not for pupil size) increased significantly in two of the three texts along with the increase in source text complexity.