bluuebunny/crossref_metadata_2025 huggingface dataset:
Redox Polymers for All-organic Batteries
Authors: Goujon Nicolas , De Pariza Xabier Lopez , Casado Nerea
Published: October 2020

All-organic batteries based on redox polymers represent an emerging new battery technology with potential application in the Internet of Things, smart packaging and clothing as well as mobile devices. Indeed, organic redox polymers feature highly attractive advantages compared to inorganic-based materials with regards to these applications, such as processability, flexibility, high rate performance, long cycle life and the ability to prepare them from renewable resources. This chapter aims to provide a comprehensive review on the current state of the art of all-organic batteries based on redox polymers, focusing on all battery prototypes reported to date and the nature of the ion carriers involved in their redox reactions. Illustrating the gradual research direction transition observed during the development of the all-organic battery technology, going from an alkali metal-based ion carrier battery system, similar to a lithium-ion battery, to a molecular ion-based and finally a proton-based ion carrier battery system. A general introduction to battery terminology and the various cell configurations is also given. Finally, future perspectives on all-organic batteries are discussed, summarizing the major challenges that remain to be overcome by the current state-of-the-art technology to unlock their commercial implementation.
PROTAC Targeting BTK for the Treatment of Ibrutinib-resistant B-cell Malignancies
Authors: Sun Yonghui , Rao Yu
Published: October 2020

This chapter covers the following sections – an introduction of Bruton’s tyrosine kinase (BTK) signaling module, an introduction of non-Hodgkin’s lymphoma and the development of BTK inhibitors followed by drug resistance and side effects, and lastly the development and prospect of BTK PROTACs.
E3-mediated Ubiquitin and Ubiquitin-like Protein Ligation: Mechanisms and Chemical Probes
Authors: Krist David T. , Schulman Brenda A.
Published: October 2020

E3 ligases drive the specificity of ubiquitin (UB) and UB-like (UBL) protein ligation. Diverse E3 structures provide distinct mechanisms achieving timely and accurate formation of covalent bonds between targeted proteins and C-terminus of UB or a UBL. Meanwhile, cellular regulation also depends on E3 ligase inhibition, activation, target prioritization and selection between UB and UBLs. This chapter summarizes recent studies revealing remarkable mechanisms of action and regulation of major classes of eukaryotic UB ligases – cullin-RING, HECT and RBR E3s – with additional focus on distinct activities of small-molecule probes that have been developed to perturb these systems for pharmaceutical and biochemical discovery purposes.
Targeting Translation Regulation for the Development of Novel Drugs
Authors: Alroy Iris , Mansour Wissam , Sheinberger Yoni
Published: October 2020

Regulation of protein translation is not restricted to global coordination, but it is also highly specific as it is an important infliction point in the regulation of gene expression, because it offers a rapid and protein-selective response to environmental cues. For example, mRNA can be transported and stored in specific cellular compartments and rapidly produced in response to a signal. Indeed, selective and specific regulation of protein translation occurs at several levels: (1) mRNA is bound by proteins immediately at transcription, enabling mRNA processing, modification (epitranscriptomics), transport, cytoplasmic localization and availability for translation; (2) proteins regulate RNA-binding proteins occupancy on target mRNAs, thereby regulating mRNA half-life and translation initiation; (3) regulation of ribosome recruitment and processivity (i.e., rate of translation). This complex regulatory machinery offers multiple targets for therapeutic intervention in protein aggregation diseases and in targeting proteins which are considered hard targets, such as structural proteins, transcription factors and scaffold and assembly proteins. We have developed a method which visualizes specific or global protein translation inside mammalian cells by monitoring the activity of ribosomes. This uniquely enables the discovery of small molecules which specifically regulate translation and leads to the identification of novel targets for therapeutic intervention.
Classes, Modes of Action and Selection of New Modalities in Drug Discovery
Authors: Valeur Eric
Published: October 2020

Drug discovery has experienced repeated waves of innovation during the last three decades. Over time, small molecules were complemented with biologics to expand the range of therapeutic opportunities. With many successful treatments reaching the market but the root causes of many pathologies remaining unaddressed, a deeper investigation into biology is creating a need for novel ways to modulate biological targets, pathways and processes. Novel waves of innovation represented by an increasing range of drug modalities are providing scientists with an expanded repertoire of mode of actions and molecules for prosecuting these. This chapter discusses these “new” modalities, which include nucleic acid-based, hyper-modified peptidic modalities as well as combinations of classical and new modalities. The targeted modes of action are reviewed along with their strengths and limitations in order to afford a perspective on the factors to consider for driving modality selection in drug discovery.
Isolation of extracellular vesicles with multivalent aptamers
Authors: Xue Fei , Chen Yundi , Wen Yi , Abhange Komal , Zhang Wenlong , Cheng Gong , Quinn Zachary , Mao Wenjun , Wan Yuan
Published: October 2020

Cancer derived extracellular vesicles can be specifically and efficiently isolated by multivalent aptamers which are prepared by rolling cycle amplification for downstream molecular analyses.
Lipid based biocompatible ionic liquids: synthesis, characterization and biocompatibility evaluation
Authors: Uddin Shihab , Chowdhury Md. Raihan , Wakabayashi Rie , Kamiya Noriho , Moniruzzaman Muhammad , Goto Masahiro
Published: October 2020

This study reports a new series of lipid-based biocompatible ionic liquids consisting of long-chain phosphonium compound, 1,2-dimyristoyl-sn-glycero-3-ethyl- phosphatidylcholine, as a cation and long chain fatty acids as anions.
Use of confocal Raman microscopy to characterise ethyl cyanoacrylate adhesive depth curing
Authors: Raheem Kevin , Cassidy John , Betts Anthony , Ryan Bernard
Published: October 2020

Confocal Raman Microscopic (CRM) set up allowing monitoring of adhesive cure in selected regions during polymerisation.
Water flow inside various geometric nano-confinement channels
Authors: Xu Xujun , Zhao Yanyan , Wang Jicheng , Zhang Ning , Wang Chunlei , Zhang Jicheng , Wei Ning
Published: October 2020

In nano-confined systems, the properties of a fluid are different from those of macroscopic systems, and the properties of a nanotube can significantly affect water transport.
Mechanistic insights into transition metal-mediated bioorthogonal uncaging reactions
Authors: Latocheski Eloah , Dal Forno Gean M. , Ferreira Thuany M. , Oliveira Bruno L. , Bernardes Gonçalo J. L. , Domingos Josiel B.
Published: October 2020

This review assesses the mechanistic aspects of transition metal-mediated uncaging reactions, with the goal of aiding the rational development of new caging groups/catalysts for chemical biology and drug-delivery applications.
Low-iridium electrocatalysts for acidic oxygen evolution
Authors: Fan Meihong , Liang Xiao , Chen Hui , Zou Xiaoxin
Published: October 2020

This frontier paper summarizes general issues relevant to iridium-catalyzed oxygen evolution in acid, and the theoretical-experimental advances in designing low-iridium electrocatalysts with reasonable activity and stability.
Flexibility and anion exchange of [(X)@Pd2L4] cages for recognition of size and charge of polyatomic anions
Authors: Lee Jeyeong , Lim Sangwoo , Kim Dongwon , Jung Ok-Sang , Lee Young-A.
Published: October 2020

A system of a Pd2L4 coordination cage was constructed, and the cage is an efficient gauge for the recognition of ubiquitous polyatomic anions.
Two new monofunctional platinum(ii) dithiocarbamate complexes:phenanthriplatin-type axial protection, equatorial-axial conformational isomerism, and anticancer and DNA binding studies
Authors: Imran Muhammad , Rehman Zia ur , Hogarth Graeme , Tocher Derek A. , Chaudhry Gul-e-Saba , Butler Ian S. , Bélanger-Gariepy Francine , Kondratyuk Tamara
Published: October 2020

In this article, we describe syntheses, characterization and anticancer action of two platinum(ii) dithiocarbamate complexes (1and2) that show quinoplatin- and phenanthriplatin-type axial protection of the Pt-plane.
Difference in ambient-personal exposure to PM2.5 and its inflammatory effect in local residents in urban and peri-urban Beijing, China: results of the AIRLESS project
Authors: Han Yiqun , Chatzidiakou Lia , Yan Li , Chen Wu , Zhang Hanbin , Krause Anika , Xue Tao , Chan Queenie , Liu Jing , Wu Yangfeng , Barratt Ben , Jones Rod , Zhu Tong , Kelly Frank J.
Published: October 2020

We quantified and compared the personal and ambient exposure to PM2.5 and the related health impact among residents in Beijing, China.
An autonomous wearable system for diurnal sweat biomarker data acquisition
Authors: Hojaiji Hannaneh , Zhao Yichao , Gong Max C. , Mallajosyula Mudith , Tan Jiawei , Lin Haisong , Hojaiji Amir M. , Lin Shuyu , Milla Carlos , Madni Asad M. , Emaminejad Sam
Published: October 2020

We present a hybrid-flex wearable system to autonomously analyze sweat—induced at programmable secretion rates—for diurnal biomarker data acquisition.
The impact of temperature and dissolved oxygen (DO) on the partial nitrification of immobilized fillers, and application in municipal wastewater
Authors: Wang Jiawei , Yang Hong , Liu Xuyan , Wang Jiawei , Chang Jiang
Published: October 2020

The immobilized filler realized the partial nitrification of municipal wastewater at low and normal temperatures.
Performance of the dye-sensitized quasi-solid state solar cell with combined anthocyanin-ruthenium photosensitizer
Authors: Prima Eka Cahya , Nugroho Harbi Setyo , Nugraha  , Refantero Gema , Panatarani Camelia , Yuliarto Brian
Published: October 2020

This work contributes to combining 12.2 mM purified anthocyanin of cyanidin-3-glucoside extracted from Indonesian black rice as the natural pigment with a ruthenium photosensitizer (1 : 1) in dye-sensitized solar cells (DSSCs) in liquid and quasi solid-state electrolytes.
Pentagraphyne: a new carbon allotrope with superior electronic and optical property
Authors: Deb Jyotirmoy , Paul Debolina , Sarkar Utpal
Published: October 2020

Herein, we have proposed a novel two-dimensional (2D) carbon allotrope, namely pentagraphyne (PG-yne), which is energetically favourable than other graphyne members, including experimentally synthesized graphyne and graphdiyne monolayer.
MicroRNA124 and microRNA21-5p regulate migration, proliferation and differentiation of rat bone marrow mesenchymal stem cells
Authors: Liu Yan , Zhang Xiaofu , Gao Chao , Zhang Hang , Zhang Hongtao , Qu Jing
Published: October 2020

Mesenchymal stem cells (MSCs) are multipotent stromal cells that can be a useful source of cells for the treatment of many diseases, including neurologic diseases. The curative effect of MSCs relies mostly on cell’s capacity of migration, proliferation and differentiation. MicroRNAs (miRNAs) are small non-coding RNAs that play important roles on regulating various cell behaviors. Here, we report that miRNA-124 (miR124) and miRNA-21-5p (miR21-5p) display different regulatory roles on migration, proliferation and neuron differentiation of MSCs. MiR124 was shown greatly promoting MSCs migration and neuronal differentiation. MiR21-5p could significantly enhance the proliferation and neuronal differentiation ability of MSCs. MiR124 and miR21-5p synergistically promote differentiation of MSCs into neurons. Collectively, miR124 and miR21-5p can functionally regulate cell migration, proliferation and neuronal differentiation of MSCs. Therefore, miR124 and miR21-5p may be promising tools to improve transplantation efficiency for neural injury.
A persistent quiet-Sun small-scale tornado
Authors: Tziotziou K. , Tsiropoula G. , Kontogiannis I.
Published: October 2020

Context. Vortex flows can foster a variety of wave modes. A recent oscillatory analysis of a persistent 1.7 h vortex flow with a significant substructure has suggested the existence of various types of waves within it.

Aims. We investigate the nature and characteristics of waves within this quiet-Sun vortex flow, over the course of an uninterrupted 48-min observing time interval, in order to better understand its physics and dynamics.

Methods. We used a cross-wavelet spectral analysis between pairs of Hα and Ca II 8542 Å intensity time series at different wavelengths and, hence, atmospheric heights, acquired with the CRisp Imaging SpectroPolarimeter at the Swedish Solar Telescope, as well as the derived Hα Doppler velocity and full width at half maximum time series. We constructed halftone frequency-phase difference plots and investigated the existence and propagation characteristics of different wave modes.

Results. Our analysis suggests the existence of Alfvénic type waves within the vortex flow that propagate upwards with phase speeds of ∼20–30 km s−1. The dominant wave mode seems to be the fast kink wave mode, however, our analysis also suggests the existence of localised Alfvénic torsional waves, which are related to the dynamics of individual chromospheric swirls that characterise the substructure of the vortex flow. The Hα V–I phase difference analysis seems to imply the existence of a standing wave pattern that is possibly arising from the interference of upwards propagating kink waves with downwards propagating ones that are reflected at the transition region or the corona. Moreover, the results provide further evidence that the central chromospheric swirl drives the dynamics of the vortex flow.

Conclusions. This is the first exhaustive phase difference analysis within a vortex flow that explores the nature and dynamics of different wave modes within it. The question, however, of whether, and how, the dissipation of the derived wave modes occurs remains open, and given that such structures are ubiquitous on the solar surface, it’s also important to investigate whether they might ultimately play a significant role in the energy budget of the upper layers of the solar atmosphere.
Déplacements induits par les tunneliers : rétro-analyse de chantiers en milieu urbain sur la base de calculs éléments finis en section courante
Authors: Berthoz Nicolas , Branque Denis , Subrin Didier
Published: October 2020

L’estimation des déplacements induits par le creusement au tunnelier sur des constructions avoisinantes (immeubles, ouvrages d’art, tunnels, réseaux…) est une étape essentielle des projets d’ouvrages souterrains en zones urbaines. De cette estimation sont, en effet, déduits ou adaptés des choix forts de conception tels que le tracé du tunnel, le dimensionnement du tunnelier (surcoupe, conicité…) et le choix de ses paramètres de pilotage (pression frontale, pression de bourrage…). Cet article présente des comparaisons entre les résultats de calculs éléments finis 2D et six sections instrumentées d’ouvrages réels. L’ensemble des paramètres nécessaires à la modélisation (modèle géotechnique et paramètres de creusement du tunnelier) est décrit de manière explicite. Ces rétro-analyses permettent de mieux cerner les paramètres clés du problème, en particulier le rôle majeur des pertes de volume induites le long de la jupe du tunnelier.
Regionale Einflüsse auf die Hausbesuchstätigkeit – Ist die ländliche Versorgung auf Dauer gesichert?
Authors: Lenz Fabian , Schübel Jeannine , Bergmann Antje , Voigt Karen
Published: October 2020

Hintergrund Demografischer Wandel und Urbanisierung schreiten in Deutschland voran. Obwohl der Versorgungsbedarf durch eine wachsende ältere und multimorbide Generation steigt, sind die Hausbesuchszahlen der Hausärzte seit Jahren rückläufig. In vorangegangenen Studien ergaben sich Hinweise, dass gerade im ländlichen Raum die Arbeitsbelastung für Hausärzte zunimmt. Fragestellung Welche strukturellen Praxismerkmale beeinflussen die Häufigkeit hausärztlicher Hausbesuche? Welchen Einfluss hat die regionalen Lage der Hausarztpraxen?

Methoden Im Rahmen einer Studie unter Hausarztpraxen in Sachsen wurden von 303 teilnehmenden Praxen in einem Zeitraum von einem Jahr 4286 Hausbesuche mittels Fragebogen dokumentiert. Jede Praxis erhob die Hausbesuche innerhalb einer randomisiert zugewiesenen Woche. Zusätzlich zu den Merkmalen der Hausbesuche wurden auch Informationen über die Praxis, wie regionale Lage, Hausbesuchsorganisation und Patientenzahlen, erfasst. Die Hausbesuchszahlen beruhen auf Angaben der befragten Ärzte. Im Nachgang wurden die Daten anhand der Postleitzahl durch Strukturinformationen des Statistischen Landesamtes sowie Versorgungsdaten der Kassenärztlichen Vereinigung (KV) ergänzt. Die Daten wurden zunächst bivariat getestet, anschließend ein multivariates Modell erstellt.

Ergebnisse Die befragten Hausärzte führten nach eigenen Angaben im Mittel 14,5 (SD 9,5) Hausbesuche pro Woche durch, was die Mitbetreuung von 32,0 (SD 30,0) Pflegeheimpatienten einschloss. Dabei korrelierte die Hausbesuchszahl bivariat signifikant negativ mit der Einwohnerzahl und signifikant positiv mit dem Altersdurchschnitt der Region. In der multivariaten Analyse zeigte sich jedoch das Alter des Arztes als größter Prädiktor für die Hausbesuche je Woche, wobei jüngere Ärzte signifikant weniger Hausbesuche durchführten.

Schlussfolgerung Die Hausbesuchszahl je Woche ist im Vergleich zu Vorstudien weiter rückläufig. Im Regressionsmodell fällt der große Einfluss des Arztalters auf die Hausbesuchsanzahl auf. Während regional-strukturelle Merkmale in den Hintergrund rücken, muss von einer veränderten Einstellung gegenüber Hausbesuchen ausgegangen werden, wobei mutmaßlich Telemedizin und Delegation in den Vordergrund treten.
Enantioselective Diels–Alder Reaction of 3-Nitrocoumarins Promoted by Chiral Organoammonium Salt Catalysts
Authors: Sakakura Akira , Fujii Yudai , Nakao Ryota , Sugihara Saki , Fujita Keita , Araki Yuya , Kudoh Takayuki , Hayakawa Ichiro , Mizoguchi Haruki
Published: October 2020

An enantioselective Diels–Alder reaction of 3-nitrocoumarins has been developed. A tryptophan-derived C
1-symmetric organoammonium thiourea catalyst promoted the reaction of 3-nitrocoumarins with Danishefsky’s diene to give the corresponding adducts with good enantioselectivity (up to 94% ee). One of the resulting adducts was converted into a chiral carbocyclic quaternary β-amino alcohol.
Using the Immune System to Manage Immunologically-Mediated Pregnancy Loss
Authors: Rajgopal Sanjana , Raghupathy Raj
Published: October 2020

Pregnancy is not nearly as successful as laypersons might assume, challenged as it is by several complications such as threatened abortion, spontaneous miscarriage, preeclampsia, and preterm delivery, among others. The maternal immune system has been shown to contribute to the etiopathogenesis of some of these pregnancy complications. Pro-inflammatory and anti-inflammatory cytokines have been studied for their effects on pregnancy because of their powerful and versatile effects on cells and tissues. This review addresses the relationship between pro-inflammatory cytokines and recurrent miscarriage, which is an important complication of pregnancy. References for this review were identified by using PRISMA-IPD (Preferred Reporting Items for a Systematic Review and Meta-analysis of Individual Participant Data) Guidelines by conducting searches for published articles from January 1, 1990 until March 1, 2020 in the following databases: PubMed, Google Scholar, and MEDLINE via OVID by the use of the search terms “recurrent spontaneous miscarriage,” “cytokines,” “progesterone,” “progestogen,” “dydrogesterone,” and “immunomodulation.” This review also presents the proposed mechanisms of action of pro-inflammatory cytokines in pregnancy loss, and then goes on to discuss the modulation of cytokine profiles to a state that is favorable to the success of pregnancy. In addition to its indispensable endocrinologic role of progesterone in pregnancy, it also has some intriguing immunomodulatory capabilities. We then summarize studies that show that progesterone and dydrogesterone, an orally-administered progestogen, suppress the production of pro-inflammatory cytokines and enhance the production of anti-inflammatory cytokines before mentioning clinical studies on progestogen supplementation. These studies support the contention that progestogens should be explored for the immunotherapeutic management of pregnancy complications.
Achieving high energy coupling in nuclear fusion with rugby shaped hohlraums
Authors: Gasparini Allison
Published: October 2020

Researchers demonstrate that through tuning the shape of Au hohlraums, they can achieve good energy coupling and symmetry for A1 capsule implosions.
Limit theorems for a random walk with memory perturbed by a dynamical system
Authors: Coletti Cristian F. , de Lima Lucas R. , Gava Renato J. , Luiz Denis A.
Published: October 2020

We introduce a new random walk with unbounded memory obtained as a mixture of the elephant random walk and the dynamic random walk, which we call the Dynamic Elephant Random Walk (DERW). As a consequence of this mixture, the distribution of the increments of the resulting random process is time dependent. We prove a strong law of large numbers for the DERW and, in a particular case, we provide an explicit expression for its speed. Finally, we give sufficient conditions for the central limit theorem and the law of the iterated logarithm to hold.
A high efficiency and low vibration liquid nitrogen cooling system for silicon crystal based x-ray optics
Authors: Lee L. , Cheng X. C. , Zhang L.
Published: October 2020

A compact low-cost cryocooling system has been designed, constructed, and tested at SLAC National Accelerator Laboratory. The cooling power is provided by natural convection and phase change of the liquid nitrogen. The initial application was to cool silicon crystal optics to the sub-100 K range. A silicon crystal of dimension (width × depth × height) 50 × 50 × 30 mm3 has been used with an electric heater on the top surface in this prototyping test. This system can effectively provide more than 80 W of cooling power to the optics with a consumption of liquid nitrogen less than 2.1 l/h. The vibration of the silicon crystal was monitored during the tests with added electric heater power on the crystal. The vibration of the silicon crystal due to liquid nitrogen boiling is negligible.
Experimental and numerical analysis of the bi-stable turbulent wake of a rectangular flat-backed bluff body
Authors: Fan Yajun , Xia Chao , Chu Shijun , Yang Zhigang , Cadot Olivier
Published: October 2020

The wake dynamics of a rectangular flat-backed bluff body is studied using both the wind tunnel experiment and Improved Delayed Detached Eddy Simulation (IDDES) at Re = 9.2 × 104. Both approaches are systematically investigated in order to provide a quantitative comparison. The wake barycenter deficit and base pressure gradient dynamics are first investigated to characterize the wake states. Second, the known global dynamics such as long-term bi-stability, vortex shedding, and wake pumping are analyzed using proper orthogonal decomposition. It is found that the wake dynamics is globally well captured by the IDDES, but with a more intense activity due to the absence of the fore-body separations observed in the experiment. The coupling of these global dynamics is explored by utilizing low-order modeling in cross planes and elaborating the evolution of the three-dimensional (3D) instantaneous wake flow from IDDES. The shedding of a large-scale hairpin vortex from the horizontal shear layer is closely associated with the pumping motion during wake switchings or switching attempts. A concept model is proposed for 3D bi-stable wake topology, which attempts to elucidate both asymmetric and symmetric wake configurations.
Symmetry tuning and high energy coupling for an Al capsule in a Au rugby hohlraum on NIF
Authors: Ping Y. , Smalyuk V. A. , Amendt P. , Khan S. , Tommasini R. , Dewald E. , Field J. E. , Graziani F. , Hartouni E. , Johnson S. , Landen O. L. , Lindl J. , MacPhee A. , Nikroo A. , Nora R. , Prisbrey S. , Ralph J. , Seugling R. , Strozzi D. , Tipton R. E. , Wang Y. M. , Kim Y. , Loomis E. , Meaney K. D. , Merritt E. , Montgomery D. , Kabadi N. , Lahmann B. , Petrasso R.
Published: October 2020

Experiments on imploding an Al capsule in a Au rugby hohlraum with up to a 1.5 MJ laser drive were performed on the National Ignition Facility (NIF). The capsule diameter was 3.0 mm with ∼1 MJ drive and 3.4 mm with ∼1.5 MJ drive. Effective symmetry tuning by modifying the rugby hohlraum shape was demonstrated, and good shell symmetry was achieved for 3.4 mm capsules at a convergence of ∼10. The nuclear bang time and the shell velocity from simulations agree with experimental data, indicating ∼500 kJ coupling with 1.5 MJ drive or ∼30% efficiency. The peak velocity reached above 300 km/s for a 120 μm-thick Al capsule. The laser backscatter inside the low-gas-filled rugby hohlraum was very low (<4%) at both scales. The high energy coupling allows implosion designs with increased adiabat, which, in turn, increases the tolerance to detrimental effects of instabilities and asymmetries. These encouraging experimental results open new opportunities for both the mainline single-shell scheme and the double-shell design toward ignition.
Experimental equation of state of 11 lanthanide nitrides (NdN to LuN) and pressure induced phase transitions in NdN, SmN, EuN, and GdN
Authors: Ehrenreich-Petersen Emma , Nielsen Morten B. , Bremholm Martin
Published: October 2020

Through an extensive data analysis of powder X-ray diffraction data obtained at pressures up to at least 78 GPa, we report the experimental equations of state for all lanthanide nitrides between NdN and LuN, excluding the radioactive Pm. By fitting the obtained unit cell volumes as a function of pressure with the third order Birch–Murnaghan equation of state, we find that the bulk modulus increases with an increasing lanthanide number from K0 = 146(12) GPa for NdN to 182(7) GPa in EuN. Hereafter, the bulk modulus reaches a plateau for the rest of the series except for TmN which has a lower bulk modulus. We find that the first derivative of the bulk modulus is around 4 for all compounds except TbN, which displays a significantly different compression behavior. In addition, we find a B1 to B10 pressure-induced phase transition in NdN, SmN, EuN, and GdN at increasingly higher pressures. In fact, we observe that the onset pressure of the phase transition increases linearly with Ln atomic number. From TbN and onwards, we do not observe any sign of a B1 to B10 transition indicating that the transition pressure exceeds the studied pressure range. Therefore, we believe that, for the heavier lanthanides, the linear relationship between the onset pressure and the lanthanide number does not hold and even higher pressures are needed to observe the transition. This coherent study of the series of lanthanide nitrides offers a unique opportunity for benchmark studies of computational methods applied to compounds with 4f electrons.
Vacancy defects induced changes in the electronic and optical properties of NiO studied by spectroscopic ellipsometry and first-principles calculations
Authors: Egbo Kingsley O. , Liu Chao Ping , Ekuma Chinedu E. , Yu Kin Man
Published: October 2020

Native defects in semiconductors play an important role in their optoelectronic properties. Nickel oxide (NiO) is one of the few wide-gap p-type oxide semiconductors and its conductivity is believed to be controlled primarily by Ni-vacancy acceptors. Herein, we present a systematic study comparing the optoelectronic properties of stoichiometric NiO, oxygen-rich NiO with Ni vacancies (NiO:VNi), and Ni-rich NiO with O vacancies (NiO:VO). The optical properties were obtained by spectroscopic ellipsometry, while valence band spectra were probed by high-resolution x-ray photoelectron spectroscopy. The experimental results are directly compared to first-principles density functional theory + U calculations. Computational results confirm that gap states are present in both NiO systems with vacancies. Gap states in NiO:Vo are predominantly Ni 3d states, while those in NiO:VNi are composed of both Ni 3d and O 2p states. The absorption spectra of the NiO:VNi sample show significant defect-induced features below 3.0 eV compared to NiO and NiO:VO samples. The increase in sub-gap absorptions in NiO:VNi can be attributed to gap states observed in the electronic density of states. The relation between native vacancy defects and electronic and optical properties of NiO are demonstrated, showing that at similar vacancy concentration, the optical constants of NiO:VNi deviate significantly from those of NiO:VO. Our experimental and computational results reveal that although VNi are effective acceptors in NiO, they also degrade the visible transparency of the material. Hence, for transparent optoelectronic device applications, an optimization of native VNi defects with extrinsic doping is required to simultaneously enhance p-type conductivity and transparency.
Active learning for robust, high-complexity reactive atomistic simulations
Authors: Lindsey Rebecca K. , Fried Laurence E. , Goldman Nir , Bastea Sorin
Published: October 2020

Machine learned reactive force fields based on polynomial expansions have been shown to be highly effective for describing simulations involving reactive materials. Nevertheless, the highly flexible nature of these models can give rise to a large number of candidate parameters for complicated systems. In these cases, reliable parameterization requires a well-formed training set, which can be difficult to achieve through standard iterative fitting methods. Here, we present an active learning approach based on cluster analysis and inspired by Shannon information theory to enable semi-automated generation of informative training sets and robust machine learned force fields. The use of this tool is demonstrated for development of a model based on linear combinations of Chebyshev polynomials explicitly describing up to four-body interactions, for a chemically and structurally diverse system of C/O under extreme conditions. We show that this flexible training database management approach enables development of models exhibiting excellent agreement with Kohn–Sham density functional theory in terms of structure, dynamics, and speciation.
Southernmost observation of a juvenile bumphead parrotfish, Bolbometopon muricatum (Valenciennes, 1840)
Authors: Martin Storm B. , Brown Kristen T. , Hoegh-Guldberg Ove
Published: October 2020

The bumphead parrotfish, Bolbometopon muricatum, is an iconic and ecologically significant species that is vulnerable to extinction. Although the Great Barrier Reef provides extensive habitat for this species, the scarcity of juvenile fish in this region may suggest that these populations rely on colonisation by adults from further north, rather than local larval recruitment. Consequently, B. muricatum populations exhibit the strongest latitudinal gradient of any parrotfish on the Great Barrier Reef. Here, we review all records of B. muricatum from the southern Great Barrier Reef and report a new observation of a juvenile at Heron Reef. This is the southernmost report of a juvenile for this species. Given its size (standard length, 25–30 cm), this individual is likely to have settled as a larval recruit in the relative vicinity of Heron Reef, rather than migrating from a more northern site on the Great Barrier Reef or beyond.
The value of a pragma-functional approach to intercultural conflict discourses
Authors: Lecompte-Van Poucke Margo
Published: October 2020

Systemic functional linguistics focuses on the study of language use within its registerial context of situation. The
theory offers a meaning-based approach for the analysis of discourses in generic and culture-specific settings. When it comes to the
analysis of conflict discourses across cultural boundaries, SFL may be integrated into a framework that relates language use to the notions
of power and ideology and the dimensions of culture and history to provide a broader picture to inform future political decision-making.
This paper presents a pragma-functional approach combining systemic functional linguistics, argumentation theory, critical theory and
postcolonial insights. The analytical tool is illustrated with reference to the New Caledonian independence debate through the analysis of
salient linguistic patterns and discursive moves in two open letters, published in April 1988 by Kanak independence leader Jean-Marie
Tjibaou and former French President François Mitterrand.
Gravitational wave signature of the fifth force for dark matter
Authors: Yue Xiao-Jun , Cao Zhoujian
Published: October 2020

Testing the equivalence principle (EP) is of great importance for fundamental physics. Whether the EP is held for dark matter (DM) is still unclear. Motivated by the recent discoveries of gravitational waves (GWs) by ground based detectors, we study the possibility of testing EP of DM by GW experiments. We consider a binary composed of a black hole (BH) and a neutron star (NS) with respect to the galactic DM as the attractor. Possibly, long-range fifth-force other than gravity between DM and ordinary matter may lead to the EP violation for DM, we investigate the effect of fifth-force acted by DM on the GW waveform of the BH-NS binary. The presence of the fifth-force will lead to a phase correction in the GW waveform which may be detectable, but the phase correction depends chaotically on the initial condition. We calculate the probability of detection for different initial conditions. The probability depends on the time interval of integration, the EP-violating driving force and the initial eccentricity. We find for appropriate conditions the probability can reach to a considerable value, and even approach to 1 in some extremal cases. For example, for most BH-NS binaries formed in the field locating as far as the solar system to the galactic center, the fifth force with the Eötvös parameter

η

DM

BH
,
NS

⩾
0.01

will result in the probability of detection >0.6 if the interval of integral time is from f = 1 Hz to the final state when the NS is disrupted by the BH. These predictions may be tested by future GW observations.
Force-free electrodynamics and foliations in an arbitrary spacetime
Authors: Menon Govind
Published: October 2020

In this paper, we formulate the relationship between force-free electrodynamics and foliations. The background metric is considered predetermined and electrically neutral, but otherwise arbitrary. As it turns out, solutions to force-free electrodynamics are intimately connected to the existence of foliations of spacetime with prescribed properties. We prove a local existence and uniqueness theorem concerning foliations when the field is non-null. In the null case, we show that there will always be a class of solutions with exactly two degrees of freedom for every admissible foliation. We are also able to also prove a singularity theorem for when non-null solutions approach the null limit. All new results are clarified with examples. For a variety in the discussion, we conclude with a solution to Maxwell’s equations in FRW cosmology.
From a central force to Kepler’s area law: student difficulties and preferences with two derivations
Authors: Oktarisa Yuvita , Karam Ricardo
Published: October 2020

In theorem 1 of his celebrated Principia, Newton showed that if one assumes a central force, Kepler’s area law follows. In this work, we report a study where two different ways of deriving this relationship, one geometrical (à la Newton) and the other analytical (using vector calculus), were presented to pre-service physics teachers. The participants were asked to formulate the essential arguments and to discuss issues that they did not understand. The findings consist of the participants’ main difficulties to understand the arguments, as well as indications of their preference for more geometrical or analytical derivations.
Giant exchange bias in micro-sized magnetic shape memory alloy particles
Authors: Liao Xiaoqi , Svedlindh Peter , Salazar-Alvarez German , Zeng Yu-Jia , Huang Rui , Yang Sen , Wang Yu
Published: October 2020

We report the effects of the magnetic ground sate and microstructure on exchange bias (EB) in ball milled Ni44Co6Mn39.5Sn10.5 alloys. A giant bias field of 1.49 T has been obtained for the micron-sized particles after 15 h milling, which is considerably larger than that of 2 h milled platelets (0.35 T) and that of the bulk alloy (0.12 T). This giant bias field is attributed to the increased volume fraction of antiferromagnetic/ferromagnetic interface, the enhanced antiferromagnetic fraction and the formed agglomerates. Our results reveal the critical roles of the magnetic ground state and microstructure of milled alloys in determining EB.
Numerical study of the effect of atomic mass of the ambient gas on the expansion and the lateral interactions of LBO plumes
Authors: Yadav Sharad K , Singh R K
Published: October 2020

The characteristics of the lateral interaction of two LBO plasma plumes in argon Ar ambient gas at high pressures were reported in a recent publication (Yadav et al 2017 J. Phys. D: Appl. Phys.
50 355201). Further, we have investigated the interaction characteristics of plumes in He, Ne, Ar and Xe gases to see the effect of atomic mass on the interaction. The present work illustrates the applicability of the present model for theoretical understanding of dynamics, structure, density variation, shock wave formations and their interactions of two propagating plasma plumes in a wide range of ambient conditions. The formation of interaction region, geometrical shape and strength of the shock fronts and subsequent regular and Mach reflections in accordance with the nature and pressure of ambient gas are successfully captured in the simulations.
Guided plasma jets directed onto wet surfaces: angular dependence and control
Authors: Parsey Guy , Lietz Amanda M , Kushner Mark J
Published: October 2020

The optimal use of atmospheric pressure plasma jets (APPJs) for treatment of surfaces—inorganic, organic and liquid—depends on being able to control the flow of plasma-generated reactive species onto the surface. The typical APPJ is a rare gas mixture (RGM) flowed through a tube to which voltage is applied, producing an RGM plasma plume that extends into the ambient air. The RGM plasma plume is guided by a surrounding shroud of air due to the higher electric field required for an ionization wave (IW) to propagate into the air. The mixing of the ambient air with the RGM plasma plume then determines the production of reactive oxygen and nitrogen species (RONS). The APPJ is usually oriented perpendicular to the surface being treated. However, the angle of the APPJ with respect to the surface may be a method to control the production of reactive species to the surface due to the change in APPJ propagation properties and the resulting gas dynamics. In this paper, we discuss results from computational and experimental investigations addressing two points—propagation of IWs in APPJs with and without a guiding gas shroud as a function of angle of the APPJ with respect to the surface; and the use of this angle to control plasma activation of thin water layers. We found that APPJs propagating out of the plasma tube into a same-gas environment lack any of the directional properties of shroud-guided jets, and largely follow electric field lines as the angle of the plasma tube is changed. Guided APPJs propagate coaxially with the tube as the angle is changed, and turn perpendicularly towards the surface only a few mm above the surface. The angle of the APPJ produces different gas dynamic distributions, which enable some degree of control over the content of RONS transferred to thin water layers.
Quantitative analysis of observed signatures in phonon reflection experiment
Authors: Li Jin
Published: October 2020

For phonons propagating in a crystal at low temperature, we develop a phonon reflection model and an analysis framework to fully understand reflection peaks from underlying physics principles. Our study shows that the specular reflection structure of peaks contains detailed information about properties of the crystal material, and provides a solid quantitative link between phonon theory and experimental signals. For both kinds of experiments that either use crystal as a particle detector or as a target material for study, this analysis provides a novel and essential method to understand the experimental signatures.
Feasibility of dosimetric measurements using Al2O3:C OSL dosimeter during fluoroscopy-guided procedures
Authors: Choi Tae Won , Chung Jin Wook , Cha Bo Kyung , Choi Kwang Nam , Park Sohyeon , Son Jeong Woo , Choi Chang Heon
Published: October 2020

This study investigated the feasibility of dosimetric measurements using Al2O3:C optically stimulated luminescence (OSL) dosimeters during fluoroscopy-guided procedures. The linearity and energy dependence of Al2O3:C OSL dosimeters were evaluated, and the air kerma rate at the operator’s position was measured. The response of Al2O3:C OSL dosimeters to short, repetitive irradiations was compared to that of long uninterrupted irradiation. The change in response of the Al2O3:C OSL dosimeter under automatic exposure rate control (AERC) was evaluated with the use of various thicknesses of polymethyl-methacrylate (PMMA) plates (15–30 cm). The Al2O3:C OSL dosimeters could detect 5 µGy and showed good linearity in doses of ≥10 µGy (R2: 0.997–0.999, p < 0.001). The relative response of the Al2O3:C OSL dosimeter normalised to that of 36.8 keV was 0.828–1.101 at the energies investigated (30.6–46.0 keV). The air kerma rate at the operator’s position was estimated to be 2.61–7.17 µGy min−1 depending on the heights representing different body parts. Repetitive short irradiations had no significant impact on the relative response of the Al2O3:C OSL dosimeters (p > 0.05). Despite a high energy dependence on the low energy beam used in fluoroscopy, the change in relative response of the Al2O3:C OSL dosimeter under AERC was within 5.7% depending on the thickness of the PMMA plates. Dosimetric measurement using Al2O3:C OSL dosimeters for patients and operators is feasible. However, one should be cautious about high standard deviations when measuring small doses of ≤20 µGy using Al2O3:C OSL dosimeters. It is essential to perform intensive bleaching before measuring very small doses to minimise pre-irradiation counts.
Variance optimization of UWB observation based on map matching for PPP/INS/UWB tightly coupled positioning
Authors: Li Zengke , Zhao Long , Wang Yifan , Yang Zhehua , Liu Zan , Wang Chengcheng
Published: October 2020

Ultra-wideband (UWB) is essential in precise point positioning (PPP)/inertial navigation systems (INS)/UWB integrated navigation with the advantage of highly accurate observations. However, its accuracy could be affected by its sparse distribution, limited operating distance and low space height. In a dynamic environment, it is not easy to determine its variance precisely for an integrated system. Sometimes, the system performs poorly due to improper variance. In this paper, a map-matching variance optimization of UWB observation was firstly developed for tightly coupled positioning. Instead of the characteristic analysis of the UWB signal directly, the optimization can be realized based on the accuracy of PPP/INS solutions. The proposed map-matching algorithm can be adopted to access the accuracy of PPP/INS and determine the optimization factor so that the variance of UWB can be dynamically obtained. Then, the variance was adopted in the stochastic model of the PPP/INS/UWB system. The actual experiments were conducted to validate the proposed method under two different scenarios, and the effectiveness of this method was analysed. The results indicated that the proposed method could obtain suitable variance and improve the performance in both these two scenarios.
A single difference-based multi-GNSS inter-system model with consideration of inter-frequency bias and inter-system bias
Authors: Shang Rui , Gao Chengfa , Gao Wang , Zhang Ruicheng , Peng Zihan
Published: October 2020

By calibrating the inter-system bias (ISB), an inter-system model can be achieved to improve the performance of multi-global navigation satellite system (GNSS) positioning. A number of studies were carried out to compose inter-system models among code division multiple access (CDMA) systems. However, due to the frequency division multiple access (FDMA) technique, GLONASS phase and code observations suffer from inter-frequency phase bias (IFPB) and inter-frequency code bias (IFCB) respectively, which make it difficult to obtain the ISB among GLONASS and CDMA systems. In addition, most of the current inter-system models are unable to handle mixed frequencies. A new single difference-based uniform inter-system model suitable for all of the CDMA and FDMA frequency combinations is proposed in this study. We first utilize a particle filter approach to extract the IFPB rate. Afterwards, the multi-ISB parameters can be estimated by the proposed model simultaneously. Four short baselines containing the signals of GLONASS, GPS, BDS3, BDS2, Galileo, and QZSS are selected to validate the model. The quantitative results indicate that the IFPB rate can be extracted precisely by a particle filter within ten epochs. The inter-system phase bias valuations are sufficiently stable on a daily scale and have standard deviation near 0.01 cycles. After de-weighting the GLONASS code observations to reduce the influence of IFCB, the inter-system code bias is also stable. Furthermore, imposing the stable ISB on the multi-GNSS inter-system model can effectively improve the single-frequency real-time kinematic positioning accuracy and reliability for severely obstructed situations with only a small number of satellites observed.
The adhesion of a mica nanolayer on a single-layer graphene supported by SiO2 substrate characterised in air
Authors: Yu Bowen , Hou Lizhen , Wang Shiliang , Huang Han
Published: October 2020

Two-dimensional nanolayers have found increasingly widespread applications in modern flexible electronic devices. Their adhesion with neighbouring layers can significantly affect the mechanical stability and the reliability of those devices. However, the measurement of such adhesion has been a great challenge. In this work, we develop a new and simple methodology to measure the interfacial adhesion between a mica nanolayer (MNL) and a single-layer graphene (SLG) supported by a SiO2 substrate. The method is based on the well-known Obreimoff method but integrated with innovative nanomanipulation and profile measuring approaches. Our study shows that the adhesion energy of MNLs on the SLG/SiO2 substrate system is considerably lower than that on the SiO2 substrate alone. Quantitative analyses reveal that the wrinkles formed on the SLG can considerably lower the adhesion. This outcome is of technological value as the adhesion maybe tailored by controlling the wrinkle formation in the graphene layer in a flexible electronic device.