bluuebunny/crossref_metadata_2025 huggingface dataset:
Prime divisors of orders of products
Authors: Moretó Alexander , Sáez Azahara
Published: January 2019

Baumslag and Wiegold have recently proven that a finite groupGis nilpotent if and only ifo(xy) = o(x)o(y) for everyx,y ∈ Gwith (o(x),o(y)) = 1. Motivated by this surprisingly new result, we have obtained related results that just consider sets of prime divisors of element orders. For instance, the first of our main results asserts thatGis nilpotent if and only if π(o(xy)) = π(o(x)o(y)) for everyx,y ∈ Gof prime power order with (o(x),o(y)) = 1. As an immediate consequence, we recover the Baumslag–Wiegold Theorem. While this result is still elementary, we also obtain local versions that, for instance, characterize the existence of a normal Sylowp-subgroup in terms of sets of prime divisors of element orders. These results are deeper and our proofs rely on results that depend on the classification of finite simple groups.
MANUSCRIPT EVIDENCE FOR ALPHABET-SWITCHING IN THE WORKS OF CICERO: COMMON NOUNS AND ADJECTIVES
Authors: O'Sullivan Neil
Published: January 2019

Of the hundreds of Greek common nouns and adjectives preserved in our MSS of Cicero, about three dozen are found written in the Latin alphabet as well as in the Greek. So we find, alongside συμπάθεια, alsosympathia, and ἱστορικός as well ashistoricus.This sort of variation has been termed alphabet-switching; it has received little attention in connection with Cicero, even though it is relevant to subjects of current interest such as his bilingualism and the role of code-switching and loanwords in his works. Rather than addressing these issues directly, this discussion sets out information about the way in which the words are written in our surviving MSS of Cicero and takes further some recent work on the presentation of Greek words in Latin texts. It argues that, for the most part, coherent patterns and explanations can be found in the alphabetic choices exhibited by them, or at least by the earliest of them when there is conflict in the paradosis, and that this coherence is evidence for a generally reliable transmission of Cicero's original choices. While a lack of coherence might indicate unreliable transmission, or even an indifference on Cicero's part, a consistent pattern can only really be explained as an accurate record of coherent alphabet choice made by Cicero when writing Greek words.
Development of a new high-current triode extraction system for helicon ion source: design and simulation
Authors: Khoshhal M. , Habibi M. , Boswell Rod W.
Published: January 2019

Three triode extraction systems are simulated by IBSimu ion optical code for Amirkabir Helicon Ion Source (AHIS). The optimized pierce and suggested parabolic electrodes are introduced for the first time in this paper. The obtained N+beam for parabolic geometry designed for ion implantation has 66 keV energy, and 10.4 mA current. Ion beam emittance and Twiss parameters of the emittance ellipse as the function ofxterm index are calculated for parabolic electrode equation. The simulated triode extraction systems have been evaluated by using of optimized parameters such as the extraction voltage, gap distance, plasma electrode (PE) aperture, and ion temperature. The extraction voltage, gap distance, PE aperture, and ion temperature have been changed in the range of 58–70 kV, 35–39 mm, 4–6 mm, and 0.5–4.4 eV in the simulations, respectively.
THE ACQUISITION OF ENGLISH DEFINITE NOUN PHRASES BY MANDARIN CHINESE SPEAKERS
Authors: Feng Shuo
Published: January 2019

By replicating Cho (2017), this article investigates how second language (L2) learners with an article-less first language acquire two types of English definiteness, anaphoric and nonanaphoric. Mandarin Chinese, as an article-less language, has a demonstrative determiner that shares the same feature set as the English definite article the: [+definite, +/-anaphoric]. In the current study, the participants were 28 advanced and 25 intermediate L1-Chinese L2-English learners and the native control data were from Cho. The results from an acceptability judgment task revealed that intermediate Chinese speakers, unlike advanced speakers, had difficulties in the nonanaphoric definite condition where, without a potential antecedent, definiteness is established through pragmatic knowledge and acquisition of nonanaphoric definiteness essentially takes place at the semantics-pragmatics interface. The findings of this article suggest that accommodating presuppositions at the semantics-pragmatics interface is challenging to L2 learners, even when feature reassembly is not required.
Measuring Development: An Intellectual and Political History of Ludwik Landau’s Scale of World Inequality
Authors: Mazurek Małgorzata
Published: January 2019

This article examines contributions of the chief economic statistician and socialist activist Ludwik Landau (1902–1944) that empirically investigated Poland’s underdevelopment in the framework of world capitalist economy. Landau pioneered a structural approach to measure the global gap between rich and poor countries in 1938–9, when such a synthetic view was largely unimaginable. Landau’s main work in international comparative statistics,World Economy, scholarly elaborated his socialist views on the necessity of non-capitalist development for Poland and other poor regions in agrarian Europe, Africa, Asia and Latin America. I argue that the Polish experience bestowed epistemic advantage in understanding the non-industrialised world and became a starting point from which to explore underdevelopment globally. This article concludes with a discussion of the political and epistemic significance of Landau’s work and how it figures in the larger history of development and statistical measurement of the world.
New tools for crop wild relative conservation planning
Authors: Magos Brehm J. , Kell S. , Thormann I. , Gaisberger H. , Dulloo M. E. , Maxted N.
Published: January 2019

Crop wild relatives (CWR) are a vital source of traits for crop improvement – therefore, conserving CWR diversity is critical to ensure food, nutrition and economic security. Efficient CWR conservation planning is a critical first step to maintain this natural resource for future use. The development of National Strategic Action Plans (NSAPs) for the conservation and sustainable use of CWR is an effective means of conservation planning and also plays an important role in sensitizing policy makers and other stakeholders to the importance of CWR. Tools to guide and facilitate countries in CWR national conservation planning and NSAP development have been prepared, namely: an ‘Interactive Toolkit for CWR Conservation Planning’, a ‘Template for the Preparation of a NSAP for the Conservation and Sustainable Use of CWR’, a ‘Template for the Preparation of a Technical Background Document for a NSAP for the Conservation and Sustainable Use of CWR’, a ‘CWR Checklist and Inventory Data Template’ and an ‘Occurrence Data Collation Template’. In this short communication, we briefly explain what these tools are, how they were developed, how they can be used and where they can be found.
Early Identification of Youth at Risk for Suicidal Behavior
Authors: Florez Ivonne Andrea , LoParo Devon , Valentine Nakia , Lamis Dorian A.
Published: January 2019

Abstract. Background: Early identification and appropriate referral services are priorities to prevent suicide. Aims: The aim of this study was to describe patterns of identification and referrals among three behavioral health centers and determine whether youth demographic factors and type of training received by providers were associated with identification and referral patterns. Method: The Early Identification Referral Forms were used to gather the data of interest among 820 youth aged 10–24 years who were screened for suicide risk (females = 53.8%). Descriptive statistics and binary logistic regressions were conducted to examine significant associations. Results: Significant associations between gender, race, and age and screening positive for suicide were found. Age and race were significantly associated with different patterns of referrals and/or services received by youths. For providers, being trained in Counseling on Access to Lethal Means was positively associated with number of referrals to inpatient services. Limitations: The correlational nature of the study and lack of information about suicide risk and comorbidity of psychiatric symptoms limit the implications of the findings. Conclusion: The results highlight the importance of considering demographic factors when identifying and referring youth at risk to ensure standard yet culturally appropriate procedures to prevent suicide.
Anisotropy in Coastal Ocean Relative Dispersion Observations
Authors: Ohlmann J. C. , Romero L. , Pallàs‐Sanz E. , Perez‐Brunius P.
Published: January 2019

Horizontal relative dispersion is investigated with Lagrangian drifter and dye tracer observations on relatively small scales (~100 to 850 m) in coastal waters. Anisotropy is quantified with an aspect ratio of the spreading in two orthogonal directions. Individual observations generally appear highly anisotropic. However, the ensemble mean computed in a coordinate system aligned with bathymetry indicates only weak anisotropy due to averaging highly anisotropic observations over a wide range of principal‐axis directions. The strong anisotropy is preserved when the mean is computed in a principle‐axis coordinate system. In fact, the ensemble mean in principle‐axis coordinates gives antidispersion or convergence in the minor‐axis direction. This result suggests gradients in buoyant materials such as spilled oil and other contaminants are not necessarily smoothed as the standard eddy‐diffusivity parameter suggests. Flow kinematics computed with clusters of four drifters indicate that approximately 72% of energy in the observed dispersing flows can be attributed to organized submesoscale structures.
Nucleation of Characteristic Earthquakes in Simulated Cycles Involving Deep Huge Slow Slip Events
Authors: Ohtani Makiko , Kame Nobuki , Nakatani Masao
Published: January 2019

The 1944 Tonankai and 1946 Nankai megathrust earthquakes are likely to have been immediately preceded by a huge slow slip event (SSE) in the deeper brittle‐to‐ductile transition zone, which accumulates slip of a meter or more within several days. The present study investigates the interaction between such huge SSEs and the characteristic earthquakes through earthquake cycle simulations obeying the rate‐ and state‐dependent friction. To simulate huge SSEs, we employ a cutoff velocity (Vcx) above which the friction changes from velocity weakening to velocity strengthening. We assume that Vcx decreases from 10 to 10−9 m/s with depth over the transition zone located between 20‐ and 35‐km depths. Depending on the characteristic slip distance L of rate and state friction, simulation results showed three patterns of earthquake nucleation. If L is small, an SSE in the transition zone directly grows into an earthquake without experiencing a separate nucleation at the brittle zone (brittle nucleation). If L is moderate, an SSE triggers brittle nucleation, which develops into an earthquake. If L is large, an SSE occurs but ceases without triggering an earthquake nor brittle nucleation, then slip deficit accumulates further to finally start brittle nucleation without the direct help of SSE, and an earthquake occurs without a large precursor. In addition, isolated huge SSEs, resembling precursory ones, occur in all cases, at most a few times per cycle.
Northern Hemisphere Blocking in ∼25‐km‐Resolution E3SM v0.3 Atmosphere‐Land Simulations
Authors: Jiang Tianyu , Evans Katherine , Branstetter Marcia , Caldwell Peter , Neale Richard , Rasch Philip J. , Tang Qi , Xie Shaocheng
Published: January 2019

The fidelity of a prerelease Energy Exascale Earth System Model (E3SM) in reproducing atmospheric blocking is evaluated with ∼100‐ and ∼25‐km horizontal resolution within ensembles of simulations with Atmospheric Modeling Intercomparison Protocol‐type active atmosphere and land surface configurations. This evaluation is conducted via a hybrid bidimensional blocking index based on geopotential height. The lower‐resolution model correctly reproduces the spatial distribution of blocking frequency maxima over the Northern Hemisphere. However, it overestimates the blocking frequency over western North America, the Pacific Northeast, and Eastern Europe regions and largely underestimates blocking frequency over the North Atlantic. The high‐resolution model significantly reduces the bias over the North Pacific region, particularly over western North America, but the biases over the North Atlantic blocking sector mostly persist. A diagnosis of the mean flow reveals that the subtropical jet is displaced poleward in the high‐resolution model with a jet core speed that is generally more realistic. A time scale analysis of eddies suggests that synoptic eddies associated with the blocking events are increased in the high‐resolution configuration. The discrepancy between the models implies that both synoptic and low‐frequency eddies play significant roles in determining North Pacific blocking, whereas North Atlantic blocking is mainly driven by low‐frequency eddies. The characteristic time scale associated with blocking events is also investigated, and it shows that both model resolutions produce events that are overly persistent. However, the bias in the high‐resolution model is reduced, which reflects more efficient energy dispersion with higher resolution.
Mechanisms for a Record‐Breaking Rainfall in the Coastal Metropolitan City of Guangzhou, China: Observation Analysis and Nested Very Large Eddy Simulation With the WRF Model
Authors: Huang Yongjie , Liu Yubao , Liu Yuewei , Li Huaiyu , Knievel Jason C.
Published: January 2019

Record‐breaking rainfall of 524.1 mm in 24 hr occurred in the coastal metropolitan city of Guangzhou, China, during 6–7 May 2017 and caused devastating flooding. Observation analysis and a nested very large eddy simulation (VLES) with Weather Research and Forecasting (WRF) model were conducted to investigate various factors that contributed to the heavy rainfall, including synoptic weather pattern, topographic effects, cold pool, and urban effects. First, the warm and moist southerly flow in the lower troposphere over the trumpet‐shaped topography of the Pearl River Delta continuously provided fuel for the development of the severe rainfall. Consequently, the southerly flow from the sea in the south strengthened with the development of the convection. Meanwhile, the precipitation‐produced weak cold pool supported a stationary outflow boundary, where new convective cells were continuously initiated and drifted downstream. The interaction between the cold outflows and the warm moist southerly flows in the lower troposphere formed a back‐building convective system, which produced local persistent heavy rainfall that lasted for more than 5 hr and reached record levels. Sensitivity experiments in which the urban area was removed from the model indicate that the urban forcing affected the timing and location of convective initiation and helped concentrate the maximum rain core. The nested WRF‐LES successfully simulated this heavy rainfall, and the model's advantages are noted for forecasting such local severe weather.
ExoMars Schiaparelli Direct‐to‐Earth Observation using GMRT
Authors: Esterhuizen S. , Asmar S. W. , De K. , Gupta Y. , Katore S. N. , Ajithkumar B.
Published: January 2019

During the ExoMars Schiaparelli separation event on 16 October 2016 and Entry, Descent, and Landing (EDL) events 3 days later, the Giant Metrewave Radio Telescope (GMRT) near Pune, India, was used to directly observe UHF transmissions from the Schiaparelli lander as they arrive at Earth. The Doppler shift of the carrier frequency was measured and used as a diagnostic to identify key events during EDL. This signal detection at GMRT was the only real‐time aliveness indicator to European Space Agency mission operations during the critical EDL stage of the mission.
How Arctic Cyclones Change the Sea Ice
Authors: P�rez Ortega Rodrigo
Published: January 2019

Whirlwinds disrupt the sea ice in the Arctic Ocean. Scientists are now beginning to understand how.
The Push Toward Local Flood Risk Assessment at a Global Scale
Authors: Kettner Albert , Schumann Guy , Tellman Beth
Published: January 2019

Flood Risk Workshop; Boulder, Colorado, 1–3 October 2018
Fueled by methane: deep-sea sponges from asphalt seeps gain their nutrition from methane-oxidizing symbionts
Authors: Rubin-Blum Maxim , Antony Chakkiath Paul , Sayavedra Lizbeth , Martínez-Pérez Clara , Birgel Daniel , Peckmann Jörn , Wu Yu-Chen , Cardenas Paco , MacDonald Ian , Marcon Yann , Sahling Heiko , Hentschel Ute , Dubilier Nicole
Published: January 2019

Sponges host a remarkable diversity of microbial symbionts, however, the benefit their microbes provide is rarely understood. Here, we describe two new sponge species from deep-sea asphalt seeps and show that they live in a nutritional symbiosis with methane-oxidizing (MOX) bacteria. Metagenomics and imaging analyses revealed unusually high amounts of MOX symbionts in hosts from a group previously assumed to have low microbial abundances. These symbionts belonged to the Marine Methylotrophic Group 2 clade. They are host-specific and likely vertically transmitted, based on their presence in sponge embryos and streamlined genomes, which lacked genes typical of related free-living MOX. Moreover, genes known to play a role in host–symbiont interactions, such as those that encode eukaryote-like proteins, were abundant and expressed. Methane assimilation by the symbionts was one of the most highly expressed metabolic pathways in the sponges. Molecular and stable carbon isotope patterns of lipids confirmed that methane-derived carbon was incorporated into the hosts. Our results revealed that two species of sponges, although distantly related, independently established highly specific, nutritional symbioses with two closely related methanotrophs. This convergence in symbiont acquisition underscores the strong selective advantage for these sponges in harboring MOX bacteria in the food-limited deep sea.
GFPLAIN250m, a global high-resolution dataset of Earth’s floodplains
Authors: Nardi F. , Annis A. , Di Baldassarre G. , Vivoni E. R. , Grimaldi S.
Published: January 2019

Identifying floodplain boundaries is of paramount importance for earth, environmental and socioeconomic studies addressing riverine risk and resource management. However, to date, a global floodplain delineation using a homogeneous procedure has not been constructed. In this paper, we present the first, comprehensive, high-resolution, gridded dataset of Earth’s floodplains at 250-m resolution (GFPLAIN250m). We use the Shuttle Radar Topography Mission (SRTM) digital terrain model and set of terrain analysis procedures for geomorphic floodplain delineations. The elevation data are processed by a fast geospatial tool for floodplain mapping available for download at https://github.com/fnardi/GFPLAIN. The GFPLAIN250m dataset can support many applications, including flood hazard mapping, habitat restoration, development studies, and the analysis of human-flood interactions. To test the GFPLAIN250m dataset, we perform a consistency analysis with floodplain delineations derived by flood hazard modelling studies in Europe.
Aroma detection using a gas sensor array with different polyaniline films
Authors: Graboski Adriana Marcia , Ballen Sandra Cristina , Galvagni Elisiane , Lazzari Thiago , Manzoli Alexandra , Shimizu Flávio Makoto , Steffens Juliana , Steffens Clarice
Published: January 2019

This paper presents a gas sensor array designed to be an electronic nose system characterized for the detection of different aromas (grape, apple, and strawberry).
Simple, fast and inexpensive large “whole water” volume sample SPE-loading using compressed air and finely ground sand
Authors: Svahn Ola , Björklund Erland
Published: January 2019

In environmental trace analysis there is often a need to enrich the compounds of interest from a large sample volume, where the use of solid phase extraction (SPE) is more or less the standard technique.
Synthesis of a miniaturized [FeFe] hydrogenase model system
Authors: Esmieu Charlène , Guo Meiyuan , Redman Holly J. , Lundberg Marcus , Berggren Gustav
Published: January 2019

How small can you go? A miniaturized hydrogenase is prepared using a synthetic peptide.
Efficient removal of both antimonite (Sb(iii)) and antimonate (Sb(v)) from environmental water using titanate nanotubes and nanoparticles
Authors: Zhao Tianhui , Tang Zhi , Zhao Xiaoli , Zhang Hua , Wang Junyu , Wu Fengchang , Giesy John P. , Shi Jia
Published: January 2019

Adsorption of Sb on the surface of TiO2NMs, and optimized TiO2{101} plane slab models for Sb(iii) and Sb(v) absorption.
‘Second-generation’ 1,2,3-triazole-based inhibitors of Porphyromonas gingivalis adherence to oral streptococci and biofilm formation
Authors: Patil Pravin C. , Tan Jinlian , Demuth Donald R. , Luzzio Frederick A.
Published: January 2019

This study details the design, synthesis and bioassay of ‘click’ peptidomimetic compounds which inhibit the adherence of P. gingivalis to S. gordonii, a primary step toward pathogenic colonization of the subgingival pocket.
Biomineralized tissue formation as an archetype of ideal grain growth
Authors: Zöllner Dana , Zlotnikov Igor
Published: January 2019

The formation of the prismatic architecture in the shell ofA. vexillumconsistently adheres to all analytical predictions of ideal grain growth.
Dispersed nano-MOFs via a stimuli-responsive biohybrid-system with enhanced photocatalytic performance
Authors: Lee Hui-Chun , Heil Tobias , Sun Jian-Ke , Schmidt Bernhard V. K. J.
Published: January 2019

MOF-based heterogeneous catalysts with enhanced dispersibility and photocatalytic property are realized via introducing pollen pivots.
Low-temperature processed inorganic perovskites for flexible detectors with a broadband photoresponse
Authors: Zhang Ting , Wang Feng , Zhang Peng , Wang Yafei , Chen Hao , Li Jian , Wu Jiang , Chen Li , Chen Zhi David , Li Shibin
Published: January 2019

The flexible perovskite photodetector, fabricated by a modified one-step method, showed a broadband spectrum response from blind ultraviolet to visible light, and exhibited excellent mechanical flexibility and improved environmental stability.
Microphase separation of carbohydrate-based star-block copolymers with sub-10 nm periodicity
Authors: Isono Takuya , Kawakami Nao , Watanabe Kodai , Yoshida Kohei , Otsuka Issei , Mamiya Hiroaki , Ito Hajime , Yamamoto Takuya , Tajima Kenji , Borsali Redouane , Satoh Toshifumi
Published: January 2019

Star-block copolymers consisting of polycaprolactone and maltotriose segments with three, four, and six arms were synthesized to achieve sub-10 nm microphase-separated structures.
n-Butyllithium catalyzed hydroboration of imines and alkynes
Authors: Yan Dandan , Wu Xueli , Xiao Jian , Zhu Zhangye , Xu Xiaojuan , Bao Xiaoguang , Yao Yingming , Shen Qi , Xue Mingqiang
Published: January 2019

Simple and convenient n-BuLi is reported as a highly efficient catalyst in promoting the hydroboration of imines and alkynes.
Cytorhizophins A and B, benzophenone-hemiterpene adducts from the endophytic fungus Cytospora rhizophorae
Authors: Liu Hongxin , Tan Haibo , Wang Wenxuan , Zhang Wenge , Chen Yuchan , Li Saini , Liu Zhaoming , Li Haohua , Zhang Weimin
Published: January 2019

(±)-Cytorhizophin A and cytorhizophin B (2), novel benzophenone-hemiterpene conjugated hetero-dimers featuring an unprecedented 6/7/6/7 tetracyclic fused ring system.
Polyphenol oxidase/gold nanoparticles/mesoporous carbon-modified electrode as an electrochemical sensing platform for rutin in dark teas
Authors: Zhong Tongsheng , Guo Qianqiong , Yin Zhifang , Zhu Xiaoyan , Liu Rong , Liu Aijuan , Huang Shasheng
Published: January 2019

By virtue of great surface area of mesoporous carbon, enhanced conductivity of AuNPs, and good electrochemical response of polyphenol oxidase to rutin, a PPO/AuNPs/FDU-15-modified electrode was used for the determination of rutin in dark teas.
Gelation and luminescence of lanthanide hydrogels formed with deuterium oxide
Authors: Zama Yusuke , Yanai Kazushige , Takeshita Juri , Ishii Ayumi , Yamanaka Masamichi , Hasegawa Miki
Published: January 2019

Luminescent lanthanide hydrogels using the low-molecular weight gelator1in D2O were developed and evaluated quantitatively.
Photoisomerization and thermal isomerization of ruthenium aqua complexes with chloro-substituted asymmetric bidentate ligands
Authors: Hirahara Masanari , Goto Hiroki , Yamamoto Rei , Yagi Masayuki , Umemura Yasushi
Published: January 2019

Introduction of a chloro substituent to the bidentate ligand of ruthenium aqua complexes enhanced photoisomerization and thermal back-isomerization.
Microstructural analysis, magnetic properties, magnetocaloric effect, and critical behaviors of Ni0.6Cd0.2Cu0.2Fe2O4 ferrites prepared using the sol–gel method under different sintering temperatures
Authors: Kouki Noura , Hcini Sobhi , Boudard Michel , Aldawas Reema , Dhahri Abdessalem
Published: January 2019

This work focuses on the microstructural analysis, magnetic properties, magnetocaloric effect, and critical exponents of Ni0.6Cd0.2Cu0.2Fe2O4 ferrites.
Enhanced gas selectivity induced by surface active oxygen in SnO/SnO2 heterojunction structures at different temperatures
Authors: Yin Guilin , Sun Jianwu , Zhang Fang , Yu Weiwei , Peng Fang , Sun Yan , Chen Xin , Xu Lei , Lu Jing , Luo Chao , Ge Meiying , He Dannong
Published: January 2019

The development of heterojunction structures has been considered as an important step for sensing materials.
Mono-emulsion droplet stretching under direct current electric field
Authors: Abbasi Muhammad Salman , Song Ryungeun , Kim Sung-Min , Kim Hyoungsoo , Lee Jinkee
Published: January 2019

Theoretical, numerical and experimental studies on transient stretching and breakup of a mono-emulsion droplet under DC electric field.
Filiform corrosion as a pressure-driven delamination process
Authors: Brau Fabian , Thouvenel-Romans Stephanie , Steinbock Oliver , Cardoso Silvana S. S. , Cartwright Julyan H. E.
Published: January 2019

A pressure-driven delamination model allows the height and width of filiform corrosion to be described when the coating thickness is varied.
A stirring system using suspended magnetically-actuated pillars for controlled cell clustering
Authors: Saberi Aref , Zhang Shuaizhong , van den Bersselaar Carola , Kandail Harkamaljot , den Toonder Jaap M. J. , Kurniawan Nicholas A.
Published: January 2019

We develop a simple, scalable stirring system that can be used for controlled clustering of particles and cells.
Hydrodynamic synchronization of pairs of puller type magnetotactic bacteria in a high frequency rotating magnetic field
Authors: Belovs Mihails , Livanovics Rudolfs , Cebers Andrejs
Published: January 2019

Ensembles of magnetotactic bacteria are known to interact hydrodynamically and form swarms under the influence of external magnetic fields. We find that synchronized doublets of bacteria are ejected from the swarms when the bacteria rotate asynchronously.
Quantitative mechanical analysis of indentations on layered, soft elastic materials
Authors: Doss Bryant L. , Rahmani Eliato Kiarash , Lin Keng-hui , Ros Robert
Published: January 2019

Atomic force microscopy (AFM) is becoming an increasingly popular method for studying cell mechanics, however the existing analysis tools for determining the elastic modulus from indentation experiments are unable to quantitatively account for mechanical heterogeneity commonly found in biological samples.
A MoS2 nanosheet–reduced graphene oxide hybrid: an efficient electrocatalyst for electrocatalytic N2 reduction to NH3 under ambient conditions
Authors: Li Xianghong , Ren Xiang , Liu Xuejing , Zhao Jinxiu , Sun Xu , Zhang Yong , Kuang Xuan , Yan Tao , Wei Qin , Wu Dan
Published: January 2019

A MoS2 nanosheet–reduced graphene oxide hybrid behaves as a high-performance and stable catalyst for ambient electrochemical N2-to-NH3 fixation.
Highly efficient and stable solid-state Li–O2 batteries using a perovskite solid electrolyte
Authors: Le Hang T. T. , Ngo Duc Tung , Didwal Pravin N. , Fisher John G. , Park Choong-Nyeon , Kim Il-Doo , Park Chan-Jin
Published: January 2019

Solid-state Li–O2 batteries using integrated solid electrolyte–cathode architectures of a perovskite conductor could operate safely in an O2 atmosphere at 25–100 °C.
Correlating lattice distortions, ion migration barriers, and stability in solid electrolytes
Authors: Kim Kwangnam , Siegel Donald J.
Published: January 2019

Strong correlations are observed between lattice distortions, thermodynamic stability, and limiting barriers for percolating ion migration in solid electrolytes.
Flexible nonfullerene organic solar cells based on embedded silver nanowires with an efficiency up to 11.6%
Authors: Dong Xinyun , Shi Pei , Sun Lulu , Li Jing , Qin Fei , Xiong Sixing , Liu Tiefeng , Jiang Xueshi , Zhou Yinhua
Published: January 2019

Flexible non-fullerene organic solar cells based on AgNWs embedded in polyimide substrates demonstrate a high efficiency up to 11.6%.
Template-free synthesis of carbon hollow spheres and reduced graphene oxide from spent lithium-ion batteries towards efficient gas storage
Authors: Natarajan Subramanian , Bajaj Hari C. , Aravindan Vanchiappan
Published: January 2019

Herein, we report the facile synthesis of carbon hollow spheres and reduced graphene oxide from separators and graphite recovered from a spent lithium-ion battery, respectively, towards a “Waste-to-Wealth” approach.
Regulation of dithiafulvene-based molecular shape and aggregation on TiO2 for high efficiency dye-sensitized solar cells
Authors: Wu Yuezhen , Zhang Quande , Li Jie , Tian Xia , Li Da , Lu Xiaoqing , Xu Bingshe , Wu Yucheng , Guo Kunpeng
Published: January 2019

Dithiafulvene-based sensitizers with different flare angles need to undergo different types of dye aggregation to maximize the performance of dye-sensitized solar cells.
Treatment of clinical T4 stage superior sulcus non-small cell lung cancer: a propensity-matched analysis of the surveillance, epidemiology, and end results database
Authors: Wen Junmiao , Liu Di , Chen Donglai , Chen Jiayan , Xu Xinyan , Chen Chang , Zhang Fuquan , Duan Shanzhou , Zhu Rongying , Fan Min , Chen Yongbing
Published: January 2019

Purpose/Objective(s): Treatments for superior sulcus non-small cell lung cancer (SS-NSCLC) have evolved, but adequate treatments of T4 disease have not been found. The aim of our study was to evaluate the prognostic factors and optimal treatment strategy for patients with T4 SS-NSCLC. Materials/Methods: We utilized the Surveillance, Epidemiology, and End Results (SEER) database (1973–2015) to identify patients diagnosed with T4 stage SS-NSCLC (according to the 7th edition American Joint Committee on Cancer (AJCC) staging system) from 2004 to 2015; those with M1 disease were excluded. Propensity score matching (PSM) with Kaplan–Meier and Cox proportional hazards’ models was performed to estimate prognosis. Results: A total of 384 patients were included. The majority was male (59.4%) at stage IIIB (56.6%), with N2 accounting for 45.3%. A total of 47 patients underwent cancer-directed surgery, while radiotherapy alone was received by 60.2% of patients. Median overall survival (OS) and lung cancer-specific survival (LCSS) were 12 and 17 months, respectively, and the 5-year OS and LCSS rates were 15.8 and 25.4%, respectively. In the matched population, the median survival outcomes were better following surgery (OS: 25 compared with 9.0 months, P<0.001; LCSS: not available (NA) compared with 11.0 months, P<0.001). Multivariate Cox analysis showed that ages ≥ 66 years (hazard ratio (HR) = 1.639, P=0.001), unmarried status (HR = 1.356, P=0.034), and tumor size ≥ 6.0 cm (HR = 1.694, P<0.001) were associated with inferior OS. Cancer-directed surgery (HR = 0.537, P=0.009) and radiotherapy (HR = 0.644, P=0.006) were independent prognostic factors for patients with T4 SS-NSCLC. Conversely, in the subgroup analysis, favorable impacts of radiotherapy were observed for nonsurgical patients (OS: HR = 0.58, P<0.001; LCSS: HR = 0.55, P<0.001). Conclusion: Our study showed that T4 stage SS-NSCLC patients had a poor prognosis. Surgical resection remains the best option for those with resectable disease. For nonsurgical T4 SS-NSCLC patients, radiotherapy should be actively considered.
DSS modulator using the SIDO dc−dc converter for the CMOS RF PA integrated circuit
Authors: Oh Sungjae , Bae Jongseok , Oh Hansik , Lim Wonseob , Yang Youngoo
Published: January 2019

A dynamic supply switching (DSS) modulator using a single‐inductor dual‐output (SIDO) dc−dc converter for complimentary metal‐oxide semiconductor (CMOS) radio frequency (RF) power amplifier (PA) integrated circuits is presented. The DSS modulator consists of the SIDO dc−dc converter and a supply switching circuit (SSC). The SIDO dc−dc converter requires only one off‐chip inductor while generating two of the dc voltages. The SSC dynamically switches the high and low dc voltages according to the modulated signal envelope. The supply switching control voltage, which is generated from the envelope, is optimised for maximum efficiency improvement. The proposed DSS PA using the SIDO dc−dc converter and the SSC was fabricated using a 0.18 μm CMOS process for a 1.75 GHz frequency band and a long‐term evolution (LTE) application. For the LTE 16‐QAM signal with the peak‐to‐average power ratio (PAPR) of 7.5 dB, the measured efficiency of the DSS PA is 33.8% at the average output power of 21 dBm, thereby satisfying the adjacent channel leakage power ratio (ACLR) level of −30.1 dBc. The measured efficiency of the DSS PA at an average output power of 15 dBm is 24.8%, which is higher than that of the stand‐alone PA by 13.3%.
Survey on topologies based on the three‐state and multi‐state switching cells
Authors: Tofoli Fernando Lessa , Tavares Douglas de Andrade , Saldanha Júlio Ismael de Assis
Published: January 2019

The introduction of the three‐state switching cell (3SSC) and the multi‐state switching cell (MSSC) has led to the proposal of several converter topologies, where prominent characteristics regarding reduced dimensions of filter elements, high efficiency, and increase of maximum power levels are achieved. Even though the active switches associated to the 3SSC and MSSC are driven by signals obtained from multiple phase‐shifted carriers similarly to the interleaving technique, there are significant differences between the aforementioned approaches. Within this context, this work intends to analyse several converter topologies employing the 3SSC and MSSC that were previously reported in the literature. An overview of important concepts regarding interleaved and 3SSC‐based converters is initially presented, as potential advantages and drawbacks are discussed in detail. Besides, it is also shown how the 3SSC and MSSC can be employed in the conception of power converter topologies for distinct applications, e.g. high‐voltage step‐up non‐isolated dc–dc converters, power factor correction rectifiers, and multilevel inverters.
Modified dual buck–boost AC/DC converter with self‐balanced DC output voltages
Authors: Wang Houqing , Wu Weimin , Gao Ning , He Yuanbin , Chung Henry Shu‐hung , Blaabjerg Frede
Published: January 2019

With wide applications of DC loads and renewable energy generation sources, the DC micro‐grid becomes more and more attractive, especially regarding active AC/DC converters. Recently, a high‐efficiency buck–boost AC/DC converter with three terminal outputs has been presented for DC micro‐grid. However, the main drawback of this converter is that the output voltages become unbalanced in the case of unequal DC loads, which causes a challenge in practical applications. In this study, a modified buck–boost AC/DC converter with self‐balanced DC output voltages is proposed. Equivalent circuits are used to analyse the operating principle of the proposed converter. As an important part of the proposed converter, the coupled inductor is designed, while the design procedure is described in detail. The dead‐beat control method is adopted to shape the waveform of the coupled inductor current. A 220 V/50 Hz/1.5 kW prototype is developed, and detailed experiments are carried out to corroborate the validity of the proposed converter.
Charge transport and accumulation around the cone‐type insulator in SF6 ‐filled 550 kV DC GIL
Authors: Zhang Bo , Guo Yujing , Yao Yongqi , Wang Zhijun , Zhang Hao , Jin Guangyao
Published: January 2019

The gas‐insulated transmission line (GIL) has the advantages of large transmission capacity, high operation reliability and environmental friendliness. It is suitable for the high voltage direct current (HVDC) power transmission of hydropower stations or nuclear power stations. However, due to the serious surface charge accumulation problem of the cone‐type insulator under DC, its flashover performance is reduced, which restricts the engineering application of HVDC GIL. In this study, a charge transport model of SF6 gas and epoxy is established for a 550 kV cone‐type insulator and the charge accumulation characteristics of the concave and convex surfaces of the cone‐type insulator are obtained. Computational results show that the gas conductivity around the cone‐type insulator is not uniform due to the charged particles drifting under a constant electric field. Compared with the AC, the difference of the electric field distribution caused by charge accumulation under DC stress is analysed. Based on the established model, the influence of the gas ion‐pair generation rate and epoxy volume conductivity on the charge accumulation on the surface of 550 kV cone‐type insulator was studied. This study is helpful to further optimise the geometry and material properties of the cone‐type insulator and reduce the surface charge accumulation and critical area electric field to improve HVDC GIL insulation design.
Topological study on electrode wells of vertical grounding electrodes of UHVDC
Authors: Chen Wei , Li Shaodong , Sun Yong , Lu Hailiang , Wen Xishan
Published: January 2019

The main body of vertical grounding electrodes of an ultra‐high‐voltage direct current (UHVDC) converter station is dispersed electrode wells, due to the shielding effect between electrode wells, the arrangement of which is a problem that needs to consider the electrical performance, the area, and the economy. The vertical grounding electrode simulation calculation model is built based on the boundary element numerical calculation software. It is found that the single circular ring is an ideal topology structure of the electrode wells, and the double circular ring structure can be adopted when the area is limited. When the double‐circle structure is adopted, current flowing through each electrode well on the inner circle is obviously lower than that on the outer circle because of the stronger shielding effect. The design proposal to increase the depth of electrode wells on the inner circle to make the distribution of current more uniform is proposed. The electrical performance difference between the arrangement of standard circular and the irregular circular is studied, and suggestions for the arrangement of irregular circular are given. The research conclusion can be used as a reference for design of vertical grounding electrodes.
Sparse Lens Inversion Technique (SLIT): lens and source separability from linear inversion of the source reconstruction problem
Authors: Joseph R. , Courbin F. , Starck J.-L. , Birrer S.
Published: January 2019

Strong gravitational lensing offers a wealth of astrophysical information on the background source it affects, provided the lensed source can be reconstructed as if it was seen in the absence of lensing. In the present work, we illustrate how sparse optimisation can address the problem. As a first step towards a full free-form-lens-modelling technique, we consider linear inversion of the lensed source under sparse regularisation and joint deblending from the lens light profile. The method is based on morphological component analysis, assuming a known mass model. We show with numerical experiments that representing the lens and source light using an undecimated wavelet basis allows us to reconstruct the source and to separate it from the foreground lens at the same time. Both the source and lens light have a non-analytic form, allowing for the flexibility needed in the inversion to represent arbitrarily small and complex luminous structures in the lens and source. In addition, sparse regularisation avoids over-fitting the data and does not require the use of an adaptive mesh or pixel grid. As a consequence, our reconstructed sources can be represented on a grid of very small pixels. Sparse regularisation in the wavelet domain also allows for automated computation of the regularisation parameter, thus minimising the impact of the arbitrary choice of initial parameters. Our inversion technique for a fixed mass distribution can be incorporated into future lens-modelling techniques iterating over the lens mass parameters.
The spatial evolution of young massive clusters
Authors: Buckner Anne S. M. , Khorrami Zeinab , Khalaj Pouria , Lumsden Stuart L. , Joncour Isabelle , Moraux Estelle , Clark Paul , Oudmaijer René D. , Blanco José Manuel , de la Calle Ignacio , Herrera-Fernandez José M. , Motte Frédérique , Salgado Jesús J. , Valero-Martín Luis
Published: January 2019

Context. There are a number of methods that identify stellar sub-structure in star forming regions, but these do not quantify the degree of association of individual stars – something which is required if we are to better understand the mechanisms and physical processes that dictate structure.

Aims. We present the new novel statistical clustering tool “INDICATE” which assesses and quantifies the degree of spatial clustering of each object in a dataset, discuss its applications as a tracer of morphological stellar features in star forming regions, and to look for these features in the Carina Nebula (NGC 3372).

Methods. We employ a nearest neighbour approach to quantitatively compare the spatial distribution in the local neighbourhood of an object with that expected in an evenly spaced uniform (i.e. definitively non-clustered) field. Each object is assigned a clustering index (“I”) value, which is a quantitative measure of its clustering tendency. We have calibrated our tool against random distributions to aid interpretation and identification of significantIvalues.

Results. Using INDICATE we successfully recover known stellar structure of the Carina Nebula, including the young Trumpler 14-16, Treasure Chest and Bochum 11 clusters. Four sub-clusters contain no, or very few, stars with a degree of association above random which suggests these sub-clusters may be fluctuations in the field rather than real clusters. In addition we find: (1) Stars in the NW and SE regions have significantly different clustering tendencies, which is reflective of differences in the apparent star formation activity in these regions. Further study is required to ascertain the physical origin of the difference; (2) The different clustering properties between the NW and SE regions are also seen for OB stars and are even more pronounced; (3) There are no signatures of classical mass segregation present in the SE region – massive stars here are not spatially concentrated together above random; (4) Stellar concentrations are more frequent around massive stars than typical for the general population, particularly in the Tr14 cluster; (5) There is a relation between the concentration of OB stars and the concentration of (lower mass) stars around OB stars in the centrally concentrated Tr14 and Tr15, but no such relation exists in Tr16. We conclude this is due to the highly sub-structured nature of Tr16.

Conclusions. INDICATE is a powerful new tool employing a novel approach to quantify the clustering tendencies of individual objects in a dataset within a user-defined parameter space. As such it can be used in a wide array of data analysis applications. In this paper we have discussed and demonstrated its application to trace morphological features of young massive clusters.
Spatial analysis of coral reefs and its degradation patterns in Bunaken National Park
Authors: Attamimi Nafil Rabbani , Saraswati Ratna
Published: January 2019

This article will analyze the spatial pattern as well as the degradation pattern of the coral reefs in the Bunaken National Park. Bunaken National Park is a marine national park located in the Province of North Sulawesi; the park was built as means of conservation as well as providing a region for tourism. The national park contains a different type of marine and land ecosystem, one of the many types of the ecosystem that are in the national park is coral reefs. Coral reefs in Bunaken National Park provides different kinds of function and benefits whether for the marine habitats that live around the ecosystem, as well as for the local people who live in the islands of the national park. Remote sensing could be used as a tool to identify the spatial pattern and the type of ecosystem that habits inside shallow sea water. The main issue with this method is that the research cannot be conduct directly to identify which type of ecosystem specifically (such as coral reefs, seagrass, etc.), as well as its condition. Therefore, data collecting is necessary to observe and identify the ecosystem and its condition specifically. This study uses satellite image from Landsat 8 OLI as the main secondary data to be processed. The satellite image will be processed by using an algorithm of shallow water analysis that was introduced by Lyzenga in 1981. Since data verification and data observation is needed for this study, the research observes the pattern of the different type of ecosystem and its condition that spreads around Bunaken National Park. The verification and observation process was done by GPS, there were 250 different samples from the data that were collected around the Bunaken National Park. The sample that was collected in the study area will be used to classify the satellite image that has been processed by shallow water algorithm, on which could identify: seagrass, bleached coral reefs, deceased coral reefs, and healthy coral reefs around the national park. The results of this study show the spatial pattern of the coral reefs is located usually around the islands in the Bunaken National Park. The results show that the coral reefs are mostly located around the islands in the National Park. The map results show that the healthy coral reefs are usually located in the outermost layer around the shallow water ecosystem. The bleached reefs are usually located in the middle section of the shallow water, between the healthy coral and the islands itself. Most of the reefs that died and bleached are in the southwest of Bunaken Island, and the northwest of Nain Island.