bluuebunny/crossref_metadata_2025 huggingface dataset:
Antiaromaticity gain increases the potential for n-type charge transport in hydrogen-bonded π-conjugated cores
Authors: Wen Zhili , Wu Judy I-Chia
Published: January 2020

Hydrogen bonding increases antiaromaticity and lowers the LUMO energy levels of non-aromatic π-conjugated cores.
From atoms to aerosols: probing clusters and nanoparticles with synchrotron based mass spectrometry and X-ray spectroscopy
Authors: Ahmed Musahid , Kostko Oleg
Published: January 2020

Synchrotron radiation provides insight into spectroscopy and dynamics in clusters and nanoparticles.
Cation-disordered rocksalt transition metal oxides and oxyfluorides for high energy lithium-ion cathodes
Authors: Clément R. J. , Lun Z. , Ceder G.
Published: January 2020

Cation-disordered rocksalt oxides and oxyfluorides are promising high energy density lithium-ion cathodes, yet require a detailed understanding of the impact of disorder and short-range order on the structural and electrochemical properties.
Tangeretin mitigates l-NAME-induced ventricular dysfunction and remodeling through the AT1R/pERK1/2/pJNK signaling pathway in rats
Authors: Wunpathe Chutamas , Maneesai Putcharawipa , Rattanakanokchai Siwayu , Bunbupha Sarawoot , Kukongviriyapan Upa , Tong-un Terdthai , Pakdeechote Poungrat
Published: January 2020

Tangeretin alleviates ventricular alterations in l-NAME hypertensive rats.
About the amplification factors in organic bioelectronic sensors
Authors: Macchia Eleonora , Picca Rosaria Anna , Manoli Kyriaki , Di Franco Cinzia , Blasi Davide , Sarcina Lucia , Ditaranto Nicoletta , Cioffi Nicola , Österbacka Ronald , Scamarcio Gaetano , Torricelli Fabrizio , Torsi Luisa
Published: January 2020

A systematic comparison between electrochemical and organic bioelectronic sensors reveals a unified rational description for a transistor amplified detection.
Reconstructing the intracellular pH microenvironment for enhancing photodynamic therapy
Authors: Wang Chaochao , Zhao Peiran , Yang Guoliang , Chen Xiaoyan , Jiang Yaqin , Jiang Xingwu , Wu Yelin , Liu Yanyan , Zhang Weian , Bu Wenbo
Published: January 2020

PA was activated by UCNP and produced H+, restructuring the intracellular pH environment and reducing TPP's aggregation to enhance PDT.
Polymerization of N-acryloylsemicarbazide: a facile and versatile strategy to tailor-make highly stiff and tough hydrogels
Authors: Fan Chuanchuan , Liu Bo , Xu Ziyang , Cui Chunyan , Wu Tengling , Yang Yang , Zhang Dongfei , Xiao Meng , Zhang Zhuodan , Liu Wenguang
Published: January 2020

A mechanical-enhancer-monomer, N-acryloylsemicarbazide, is polymerized to make an ultra-stiff supramolecular polymer hydrogel that is exploited as a temporary vascular prosthesis.
Dinuclear copper(ii) complexes containing oxamate and blocking ligands: crystal structure, magnetic properties, and DFT calculations
Authors: Simões Tatiana R. G. , do Pim Walace D. , Metz Karina C. , Ribeiro Marcos A. , Valente Daniel C. A. , Cardozo Thiago M. , Pinheiro Carlos B. , Pedroso Emerson F. , Horta Bruno A. C. , Pereira Cynthia L. M. , de Souza Gilmar P. , Stumpf Humberto O.
Published: January 2020

Dicopper(ii) complexes were prepared as promising platforms for the design of polynuclear systems providing an avenue toward new molecule-based materials.
Computational prediction of interaction and pharmacokinetics profile study for polyamino-polycarboxylic ligands on binding with human serum albumin
Authors: Chadha Nidhi , Singh Dushyant , Milton Marilyn D. , Mishra Gauri , Daniel Joseph , Mishra Anil K. , Tiwari Anjani K.
Published: January 2020

Human serum albumin (HSA) is one of the most abundant plasma proteins available in blood and responsible for transport of fatty acids, drugs and metabolites at its binding sites which are very important for the assessment of pharmacokinetics profile of the polyamino-polycarboxylic ligands.
Theoretical study on degradation mechanism of ornidazole on anatase TiO2(101) and (001) surfaces
Authors: Wang Danyang , Qin Haichuan , Qin Qiaoqiao , Liu Xiang-Yang , Li Laicai
Published: January 2020

The degradation mechanism of one new emerging pollutant ornidazole (ONZ) on TiO2surface is explored using DFT calculations.
Mechanically tunable exchange coupling of Co/CoO bilayers on flexible muscovite substrates
Authors: Ha Thai Duy , Yen Min , Lai Yu-Hong , Kuo Chang-Yang , Chen Chien-Te , Tanaka Arata , Tsai Li-Zai , Zhao Yi-Feng , Duan Chun-Gang , Lee Shang-Fan , Chang Chun-Fu , Juang Jenh-Yih , Chu Ying-Hao
Published: January 2020

A mechanical bending method was utilized to apply strain to flexible Co/CoO bilayers and control the exchange coupling between the two layers.
Stereoselective synthesis of amino-substituted cyclopentafullerenes promoted by magnesium perchlorate/ferric perchlorate
Authors: Ma Wan , Wang Kun , Huang Cheng , Wang Hui-Juan , Li Fa-Bao , Sun Rui , Liu Li , Liu Chao-Yang , Asiri Abdullah M.
Published: January 2020

A reaction of [60]fullerene with cinnamaldehydes and amines promoted by magnesium perchlorate/ferric perchlorate stereoselectively afforded a series of novel amino-substituted cyclopentafullerenes.
Visible-light-promoted radical cross-coupling of para-quinone methides with N-substituted anilines: an efficient approach to 2,2-diarylethylamines
Authors: Wu Qiao-Lei , Guo Jing , Huang Gong-Bin , Chan Albert S. C. , Weng Jiang , Lu Gui
Published: January 2020

A series of 2,2-diarylethylamines were accessed via visible-light-promoted radical cross-coupling of p-QMs with N-alkyl anilines.
Visible-light-mediated photocatalytic cross-coupling of acetenyl ketones with benzyl trifluoroborate
Authors: Zhang Lingchun , Chu Yanle , Ma Peizhi , Zhao Shujuan , Li Qiaoyan , Chen Boya , Hong Xuejiao , Sun Jun
Published: January 2020

A visible-light-mediated photocatalytic strategy for the radical–radical cross-coupling of acetenyl ketones with benzyl trifluoroborate has been described.
Recent progress in the total synthesis of Strychnos alkaloids
Authors: He Weigang , Wang Pengyan , Chen Junhan , Xie Weiqing
Published: January 2020

The recent synthetic approaches toward Strychnos alkaloids are summarized, including novel synthetic methodologies and strategies.
Recent progress in the total synthesis of marine brominated sesquiterpene aplydactone
Authors: Chen Renzhi , Yang Sihan , Zhang Yandong
Published: January 2020

In this review, we summarize five instructive total syntheses of marine brominated sesquiterpene aplydactone developed over the past five years.
Chimeric γPNA–Invader probes: using intercalator-functionalized oligonucleotides to enhance the DNA-targeting properties of γPNA
Authors: Emehiser Raymond G. , Hrdlicka Patrick J.
Published: January 2020

Chimeric γPNA–Invader probes are energetically activated to recognize complementary double-stranded (ds) DNA targets and engineered to reduce γPNA dimerization and improve the specificity of the recognition process vis-à-vis single-stranded γPNAs.
Photopolymerization with AIE dyes for solid-state luminophores
Authors: Zhao Di , You Jian , Fu Hongyuan , Xue Tanlong , Hao Tingting , Wang Xiaoning , Wang Tao
Published: January 2020

The photoinitiating activities of MPAs/ONI were evaluated. The AIE emission of MPAs occurred during photocuring. MPAs showed potential as fluorescent molecular probes to monitor the progress of photopolymerization.
Metal-free iminyl radical-mediated C–C single bond cleavage/functionalization of redox-active oxime esters
Authors: Zhang Miao-Miao , Li Shi-Hong , Tu Jia-Lin , Min Qing-Qiang , Liu Feng
Published: January 2020

By photoactivating Hantzsch ester (HE) to act as an electron donor, we have achieved single-electron reduction of cycloketone oxime esters, thus providing a novel catalyst-free strategy for alkylation, allylation, vinylation and alkynylation.
Coulomb decay rates in monolayer doped graphene
Authors: Chiu Chih-Wei , Chung Yue-Lin , Yang Cheng-Hsueh , Liu Chang-Ting , Lin Chiun-Yan
Published: January 2020

Excited conduction electrons, conduction holes, and valence holes in monolayer electron-doped graphene exhibit unusual Coulomb decay rates.
High-throughput liquid chromatography mass-spectrometry-driven lipidomics discover metabolic biomarkers and pathways as promising targets to reveal the therapeutic effects of the Shenqi pill
Authors: Li Wen-xiu , Zhang Ai-hua , Zhou Xiao-hang , Nan Yang , Liu Qi , Sun Hui , Fang Heng , Wang Xi-jun
Published: January 2020

Lipidomics, a branch of metabonomics, could provide a powerful technique for discovery of lipid molecules to reveal disease status and drug efficacy.
R-VAPOL-phosphoric acid based1H and13C-NMR for sensing of chiral amines and acids
Authors: Prasad Durga , Mogurampelly Santosh , Chaudhari Sachin R.
Published: January 2020

R-VAPOL-chiral solvating agent for discrimination of chiral amines and acids using1H and13C NMR.
Recycling of waste ceramic foams as fine aggregates in pervious concrete
Authors: Jiang Congcong , Cheng Xin
Published: January 2020

The recycling of waste ceramic foams as fine aggregates to prepare a high strength pervious concrete (HSPC) was investigated.
Sandwich-structured poly(vinylidene fluoride-hexafluoropropylene) composite film containing a boron nitride nanosheet interlayer
Authors: Chen Fujia , Zhou Yujiu , Guo Jimin , Sun Song , Zhao Yuetao , Yang Yajie , Xu Jianhua
Published: January 2020

A novel composite material formed by adding high dielectric inorganic ceramic particles and BNNSs interlayer into a sandwich-structured film.
Synthesis of thermoresponsive oligo(ethylene glycol) polymers through radical ring-opening polymerization of vinylcyclopropane monomers
Authors: Stanojkovic Jovana , Oh Junki , Khan Anzar , Stuparu Mihaiela C.
Published: January 2020

Polyvinylcyclopropanes are designed to exhibit a thermally triggered aggregation process in aqueous solutions.
Mechanistic insight into the non-hydrolytic sol–gel process of tellurite glass films to attain a high transmission
Authors: Pan Xuanzhao , Zhao Jiangbo , Qian Gujie , Zhang Xiaozhou , Ruan Yinlan , Abell Andrew , Ebendorff-Heidepriem Heike
Published: January 2020

This work develops a high-transparency amorphous film with a wide transmission window and high refractive index, which can potentially meet the strong demand of integrating functional nanoparticles for the next-generation hybrid optoelectronic films.
A novel two-photon ratiometric fluorescent probe for imaging and sensing of BACE1 in different regions of AD mouse brain
Authors: Ge Lihong , Liu Zhichao , Tian Yang
Published: January 2020

A two-photon ratiometric fluorescent probe was first developed for imaging and sensing of BACE1 in live neurons and deep tissues.
Molecularly engineered hole-transport material for low-cost perovskite solar cells
Authors: Pashaei Babak , Bellani Sebastiano , Shahroosvand Hashem , Bonaccorso Francesco
Published: January 2020

Organic hole transport materials (HTMs) strongly affect the cost of efficient perovskite solar cells. In this work, a newly engineered HTM based on triphenylamine is proposed as a cheap alternative to efficient organic HTMs (e.g., spiro-OMeTAD).
A subtle relationship between substrate stiffness and collective migration of cell clusters
Authors: Balcioglu Hayri E. , Balasubramaniam Lakshmi , Stirbat Tomita Vasilica , Doss Bryant L. , Fardin Marc-Antoine , Mège René-Marc , Ladoux Benoit
Published: January 2020

The physical cues from the extracellular environment mediates cell signaling spatially and temporally.
Membrane rolling induced by bacterial toxins
Authors: Berg Klenow Martin , Camillus Jeppesen Jonas , Simonsen Adam Cohen
Published: January 2020

Shiga and cholera toxins induce curvature and rolling of planar double supported model membrane patches.
Swelling, dewetting and breakup in thin polymer films for cultural heritage
Authors: Castel Amélie , Gutfreund Philipp , Cabane Bernard , Rharbi Yahya
Published: January 2020

The removal of ultrathin amorphous polymer films in contact with nonsolvent/solvent binary mixtures is addressed by means of neutron reflectometry and atomic force microscopy.
Synthesis of two-dimensional hematite and iron phosphide for hydrogen evolution
Authors: Mohiuddin Md , Zavabeti Ali , Haque Farjana , Mahmood Asif , Datta Robi S. , Syed Nitu , Khan Muhammad Waqas , Jannat Azmira , Messalea Kibret , Zhang Bao Yue , Chen Guanyu , Zhang Haijiao , Ou Jian Zhen , Mahmood Nasir
Published: January 2020

Ultrathin α-Fe2O3 and FeP are synthesized by engineering the lattice matching degree between water-soluble template and target material for hydrogen evolution reaction.
Engineering microporous ethane-trapping metal–organic frameworks for boosting ethane/ethylene separation
Authors: Pei Jiyan , Wang Jia-Xin , Shao Kai , Yang Yu , Cui Yuanjing , Wu Hui , Zhou Wei , Li Bin , Qian Guodong
Published: January 2020

The pore size and low-polarity pore surface are systematically engineered within a series of C2H6-selective MOF materials for targeting high C2H6 uptake capacity, high C2H6/C2H4 selectivity and moderate C2H6 adsorption heat simultaneously.
A facile route to fabricate double atom catalysts with controllable atomic spacing for the r-WGS reaction
Authors: Chen Hongyu , Zhang Ying , He Qian , Zhang Hao , Xu Sheng , He Xiaohui , Ji Hongbing
Published: January 2020

Four double atom catalysts (DACs) with controllable interatomic distances were achieved via solventless ball-milling, among which double-atom Ni2/N–C showed good selectivity and superior catalytic activity to single-atom Ni1/N–C for r-WGS reactions.
Tetrafluorinated phenylpyridine based heteroleptic iridium(iii) complexes for efficient sky blue phosphorescent organic light-emitting diodes
Authors: Chen Zhao , Suramitr Songwut , Zhu Nianyong , Ho Cheuk-Lam , Hannongbua Supa , Chen Shuming , Wong Wai-Yeung
Published: January 2020

Tetrafluorinated phenylpyridine has been used to achieve sky blue-emitting iridium(iii) phosphors and their organic light-emitting diodes exhibit high external quantum efficiencies (∼20%) with cyan emission colours.
Benzimidazole–triazine based exciplex films as emitters and hosts to construct highly efficient OLEDs with a small efficiency roll-off
Authors: Liang Baoyan , Wang Jiaxuan , Cui Yuanyuan , Wei Jinbei , Wang Yue
Published: January 2020

Highly efficient exciplex-based OLEDs were fabricated by employing acceptors composed of benzimidazole and triazine hybrids.
Immobilized DNA aptamers used as potent attractors for vascular endothelial cell: in vitro study of female rat
Authors: Cha Jung-Joon , Lee Hoyeon , Kim Miyoung , Kang Juyoung , Song Hanlim , Kim Min-Gon , Lee Jong-Hyun
Published: January 2020

Vascular endothelial cells are essential to vascular function and maintenance. Dysfunction of these cells can lead to the development of cardiovascular disease or contribute to tumorigenesis. As such, the therapeutic modulation and monitoring of vascular endothelial cells are of significant clinical interest, and several endothelial-specific ligands have been developed for drug delivery and the monitoring of endothelial function. However, the application of these ligands has been limited by their high cost and tendency to induce immune responses, highlighting a need for alternate methods of targeting vascular endothelial cells. In the present study, we explore the therapeutic potential of DNA aptamers. Using cell-SELEX technology, we identified two aptamers with specific binding affinity for vascular endothelial cells and propose that these molecules show potential for use as new ligands for drug and biomarker research concerning vascular endothelial cells.
Methods assessment of self-tanning of rapeseed and sunflower meal fractions enriched in proteins and phenolic compounds using in vitro measurement of protein rumen degradability
Authors: Broudiscou Laurent-Philippe , Laguna Oscar , Lecomte Jérôme , Solé-Jamault Véronique , Dauguet Sylvie
Published: January 2020

Two protein tanning methods were evaluated to contribute to the withdrawal of formaldehyde as a tanning agent of meals for feeding ruminants. The experimental materials were two fractions of rapeseed and sunflower meals collected at the positive electrode of an electrostatic separator, presenting high contents in proteins and phenolic compounds. The objective was to make phenolics and proteins interact without addition of exogenous tannins. Treatment CH incubated a meal fraction:water mixture (1:2, w:w) for 48 h at 50 °C. Treatment FR incubated a meal fraction:water mixture (1:10, w:w) at pH 9.0 for 48 h at 4 °C. Microbial proteolysis on meal fractions were quantified during 24 h rumen batch fermentations with cellulose and starch as nitrogen-free energy sources. The net production of ammonia tended to be reduced by treatment FR mostly on rapeseed, corresponding to an 8% saving of rapeseed meal proteins degradable in the rumen. When untreated, the sunflower fraction decreased methane production by 50%, while treatments restored the fermentation pattern. Cold alkaline treatment could be considered to protect meal proteins from degradation by rumen micro-organisms.
Strategy of economic and social development of St. Petersburg until 2030 achievement
Authors: Kalchenko Olga , Evseeva Svetlana , Evseeva Oksana , Plis Kristina
Published: January 2020

The paper focuses on the goals' achievements of the Strategy of economic and social development of St. Petersburg until 2030. Strategic directions of St. Petersburg development until 2030 (human capital development, improving urban environment, providing sustainable economic growth, ensuring effective governance and civil society development) are examined. The feasibility of economic and social development indicators, predicted in 2012 for 2020 and 2030, is verified on the basis of actual data for 2016. The indicators, predicted values of which are hard-to-reach and require revision, are revealed. Such indicators are: employed in economy, percent of people with higher education, workplaces with high labor productivity and foreign investment in economy of St. Petersburg. The paper examines the dynamics of the main indicators presented by the Committee for Economic Policy and Strategic Planning of St. Petersburg. The list of indicators is not exhaustive. The Strategy is based on the UN sustainable development goals and one of its scenarios has prospects for implementation.
Cross-national analysis of the older workers’ employment rate
Authors: Kratt Oleh , Kirnos Inna
Published: January 2020

The share of older people in population structure is constantly rising in developed countries. This leads to a decrease of working age population. Labor market situation of Eastern European countries is aggravated by labor force migration. An effective response to challenges of ageing is productive ageing policy aimed at attracting older workers to labor market. The countries with remarkable success in older workers’ employment are defined in the article. Research method – analysis of extreme values repeatability (5 leading countries and 5 outsider ones) of the statistical sample. An object of the study – is replenishment of human resources at the national labor market. Subject of the study is involving older workers to national labor market. There are three stages of the study. The first stage is ranking the countries according to the older workers’ capability to implement their professional qualities at the labor market on a global scale. Capability domain of Global Age Watch Index is chosen as a criterion for ranking. Relative stability (the composition of countries) and relative volatility (annual change of country indicators’ value) are the features of the leaders’ group. The main feature of the outsider’s group is absence of the state policy towards older workers’ employment. The second stage of the study is ranking OECD countries by older workers’ employment rate. PWC Golden Age Index. Is chosen as a criterion of ranking The values of the criterion is a result of the common policy in the framework of intergovernmental agreements. The proof is positive dynamics of the criterion in both groups. The third stage of study is ranking European countries by duration of the working life. State policy of productive ageing is directed towards prolongation of working life. So, direction of seniority duration characterizes policy effectiveness. Extreme values of seniority demonstrate mutual loyalty of the employers and employees. The decrease in the highest values of seniority and the suspension of their pace of dynamics suggests the existence of an upper limit of seniority. The growth rate of low values of seniority is increasing, which proves the mobility of the bottom line.
Comparison of neural networks and regression time series in predicting export from Czech Republic into People´s Republic of China
Authors: Krulický Tomáš , Brabenec Tomáš
Published: January 2020

The People´s Republic of China is one of the largest, but also the most demanding markets in the world. The trade is limited by a number of barriers, strong competition and unusual environment for trades from other parts of the world. Despite those limitations, Czech exporters are able to establish themselves in the Chinese market, exporting mainly machines and vehicles. To predict future export trends is very difficult; however, these predictions can be crucial not only for individual exporters but also for the whole national economy. For predictions, economists use causal, intuitive or statistical methods. The objective of the contribution is to compare the accuracy of equalizing time series by means of regression analysis and artificial neural networks for a possible prediction of future export trends on the example of the Czech Republic export to the People´s Republic of China. For the purposes of analysis by means of statistical methods, the data obtained from monthly statements from the period starting from the year 2000 and ending in July 2018. First, a linear regression is carried out and subsequently, neural networks are used for regression. Finally, the results are compared. It appeared that in practice, mainly all retained neural networks are applicable. However, the first of them showed significant deviations within a very short period of time.
The marketing value creation in the waste management sector – multi-conceptual business model
Authors: Sztangret Izabela Barbara
Published: January 2020

The concept of marketing value occurred interesting due to a result of the process of transformation of traditional business relationships into specific type of cooperation of enterprises to create multivalued for demanding customers. It also concerns studied companies of the sector of waste collection and recycling, as well as their partners and customers. In the studied case, marketing value is created by enterprises, their cooperants and customers for the purpose of further satisfaction of target market need, in at least three-spherical business model. This model often has multi-concept, or holistic nature while combining relationship marketing, supply marketing, integral, internal, systemic, strategic and social marketing. Companies representing the sector of waste management apply smart technological solutions which result in interactive formation of market value. Smart ways of creation of marketing value, in the sector of waste management enterprises in the environment of IT solutions is the goal of this paper. The main research methods used are case studies.
Increasing the availability of financial services in remote, sparsely populated and hard-to-reach regions through the development of an entrepreneurial initiative in rural tourism
Authors: Vasyukova Lyudmila , Masyuk Natalya , Bushueva Marina , Bessonova Anastasiya , Mosolova Nina A.
Published: January 2020

Activities to increase the availability of financial services are the primary task of the state economic policy. The formation of an active consumer of financial services is possible through the development of entrepreneurial activity among residents of remote areas, whose sparse population can become a competitive advantage. World experience in rural tourism development has shown that it is the sparsely populated, remote rural settlements from industrial centers that make them attractive for potential users of tourist services that are supplied by local people: tourist accommodation, catering, souvenir production, etc. This article presents the results of a study of the level of physical accessibility of financial services for residents of the Pozharsky district of Primorsky Krai, as well as their level of satisfaction with financial products and services. The study was conducted in 2018-2019. The main goal of the article is to examine the problems of ensuring financial affordability in remote, hard-to-reach and sparsely populated regions by the example of Pozharsky District, Primorsky Region of the Russian Federation. Measures are proposed to increase the availability of financial services through the development of entrepreneurial initiative of the inhabitants of the region.
Considering seasonal fluctuations on balancing time series with the use of artificial neural networks when forecasting US imports from the PRC
Authors: Vrbka Jaromír , Vochozka Marek
Published: January 2020

The paper’s objective is to propose a particular methodology to be used to regard seasonal fluctuations on balancing time series while using artificial neural networks based on the example of imports from the People's Republic of China (PRC) to the USA (US). The difficulty of forecasting the volume of foreign trade is usually given by the limitations of many conventional forecasting models. For the improvement of forecasting it is necessary to propose an approach that would hybridize econometric models and artificial intelligence models. Data for an analysis to be conducted are available on the World Bank website, etc. Information on US imports from the PRC will be used. Each forecast is given by a certain degree of probability which it will be fulfilled with. Although it appeared before the experiment that there was no reason to include the categorical variable to reflect seasonal fluctuations of the USA imports from the PRC, the assumption was not correct. An additional variable, in the form of monthly value measurements, brought greater order and accuracy to the balanced time series.
A method for real-time identification and tracking of traveling ionospheric disturbances using ionosonde data: first results
Authors: Altadill David , Segarra Antoni , Blanch Estefania , Juan José Miguel , Paznukhov Vadym V. , Buresova Dalia , Galkin Ivan , Reinisch Bodo W. , Belehaki Anna
Published: January 2020

Traveling Ionospheric Disturbances (TIDs) are wave-like propagating irregularities that alter the electron density environment and play an important role spreading radio signals propagating through the ionosphere. A method combining spectral analysis and cross-correlation is applied to time series of ionospheric characteristics (i.e., MUF(3000)F2 or foF2) using data of the networks of ionosondes in Europe and South Africa to estimate the period, amplitude, velocity and direction of propagation of TIDs. The method is verified using synthetic data and is validated through comparison of TID detection results made with independent observational techniques. The method provides near real time capability of detection and tracking of Large-Scale TIDs (LSTIDs), usually associated with auroral activity.
Current state and perspectives of Space Weather science in Italy
Authors: Plainaki Christina , Antonucci Marco , Bemporad Alessandro , Berrilli Francesco , Bertucci Bruna , Castronuovo Marco , De Michelis Paola , Giardino Marco , Iuppa Roberto , Laurenza Monica , Marcucci Federica , Messerotti Mauro , Narici Livio , Negri Barbara , Nozzoli Francesco , Orsini Stefano , Romano Vincenzo , Cavallini Enrico , Polenta Gianluca , Ippolito Alessandro
Published: January 2020

Italian teams have been involved many times in Space Weather observational campaigns from space and from the ground, contributing in the advancing of our knowledge on the properties and evolution of the related phenomena. Numerous Space Weather forecasting and now-casting modeling efforts have resulted in a remarkable add-on to the overall progress in the field, at both national and international level. The Italian Space Agency has participated several times in space missions with science objectives related to Space Weather; indeed, an important field for the Italian scientific and industrial communities interested in Heliophysics and Space Weather, is the development of new instrumentation for future space missions. In this paper, we present a brief state-of-the-art in Space Weather science in Italy and we discuss some ideas on a long-term plan for the support of future scientific research in the related disciplines. In the context of the current roadmap, the Italian Space Agency aims to assess the possibility to develop a national scientific Space Weather data centre to encourage synergies between different science teams with interest in the field and to motivate innovation and new mission concept development. Alongside with the proposed recommendations, we also discuss how the Italian expertise could complement international efforts in a wider international Space Weather context.
Welches (ist das richtige) Target bei nichtalkoholischer Fettleber (NAFLD)
Authors: Huber Yvonne , Galle Peter R. , Schattenberg Jörn M.
Published: January 2020

Die nichtalkoholische Fettleber (NAFLD) ist die am stärksten zunehmende Lebererkrankung weltweit. Vielen Patienten gelingt es nicht, durch eine Änderung des Lebensstils einen positiven Einfluss auf die Erkrankung zu erzielen, und der Bedarf an einer pharmakologischen Therapie in dieser Gruppe ist hoch. In Analogie zu anderen metabolischen Erkrankungen wie z. B. dem Diabetes mellitus Typ 2 oder Fettstoffwechselstörungen wird vermutlich ein großer Teil von Patienten eine dauerhafte medikamentöse Therapie benötigten. Derzeit sind mehrere Substanzen mit verschiedenen pathophysiologischen Ansätzen in klinischer Testung. Dabei können metabolische, antiinflammatorische und antifibrotische Wirkmechanismen unterschieden werden. Mehrere Substanzen befinden sich bereits in Phase-3-Studien. Dazu zählen Elafibranor (PPAR-α/δ-Agonist), Cenicriviroc (CCR2/CCR5-Inhibitor), Obeticholsäure (FXR-Agonist), Aramchol (SCD1-Modulator) und Resmetrion (Thyroid-Hormon-Rezeptor-beta-Agonist). Weitere Studien mit pathophysiologisch vielversprechenden Wirkmechanismen, z. B. dem ASK-1-Inhibitor Selonsertib oder dem Caspase-Inhibitor Emricasan, haben bislang negative Ergebnisse gezeigt, werden jedoch z. T. in Kombinationstherapien weiter evaluiert. Die komplexe Pathophysiologie der Erkrankung, die Entzündung, Stoffwechsel und Fibrose verknüpft, hat dazu geführt, dass auch Kombinationen mehrerer Substanzen mit verschiedenen Wirkansätzen untersucht werden. Die vorliegende Übersicht fasst die Ende 2019 in klinischen Studien der Phase 3 befindlichen Substanzen für Patienten mit NASH ohne Leberzirrhose zusammen.
Diastereopure Synthesis of Novel Cyclohexane-Ring-Based Constrained Lanthionine and α-Methyllanthionine through an SN2 Reaction with a β-Bromoalanine as a Key Step
Authors: Osante Iñaki , Cativiela Carlos , Gracia-Vitoria Jaime , Carretero Ángel
Published: January 2020

Here we report the diastereopure synthesis of a novel protected lanthionine derivative substituted with a cyclohexane ring as well as the diastereopure synthesis of an α-methyllanthionine derivative. By starting from enantiopure α,β-cyclohexane-substituted cystine, or α-methylcysteine, we designed a straightforward route that permits the preparation of orthogonally protected modified lanthionines in diastereopure form. The key step of the methodology is the formation of a thioether bond through the use of an β-bromoalanine derivative. The strategy developed should be valuable in the preparation of a wide range of modified constrained lanthionines that might be finally attached to a peptide sequence, which would be especially useful in the syntheses of novel lantibiotics.
Reduction of threading dislocation density in top-down fabricated GaN nanocolumns via their lateral overgrowth by MOCVD
Authors: Zubialevich Vitaly Z. , McLaren Mathew , Pampili Pietro , Shen John , Arredondo-Arechavala Miryam , Parbrook Peter J.
Published: January 2020

Reduction of threading dislocation density in top-down fabricated GaN nanocolumns (NCs) via their successive lateral shrinkage by anisotropic wet etch and lateral overgrowth by metalorganic chemical vapor deposition is studied by transmission electron microscopy. The fabrication process involves a combination of dry and wet etches to produce NC arrays of a low fill factor (<5%), which are then annealed and laterally overgrown to increase the array fill factor to around 20%–30%. The resulting NC arrays show a reduction in threading dislocation density of at least 25 times, allowing for the reduction in material volume due to the array fill factor, with dislocations being observed to bend into the voids between NCs during the overgrowth process.
Nanomechanical modulation cavities of localized surface plasmon resonance with elastic whispering-gallery modes
Authors: Oumekloul Z. , Moutaouekkil M. , Lévêque G. , Talbi A. , Mir A. , Akjouj A.
Published: January 2020

The dispersion of mechanical vibration limits nano-optomechanical modulation. In this work, we propose an optomechanical modulation exploiting elastic local resonances, also called whispering-gallery modes (WGMs). We find that our structure supports two quadripolar and two hexapolar elastic WGMs, which are nondispersive to avoid losses where the displacement field is localized on the gold nanodisks (AuNDs). We numerically demonstrate that the coupling between localized surface plasmon resonance (LSPR) and WGMs are relative both to the symmetry displacement of the elastic modes and to the strong isolation of phononic modes in the AuNDs. The amplitude of the modulation is evaluated by computing the wavelength shift of dipolar LSPR under different deformations by four WGMs. A detailed comparison between the four WGMs allows us to determine the ones with more efficient coupling. Furthermore, this simultaneous confinement gives a large acousto-plasmonic coupling that can be used to design a new mechanical sensor with the plasmonic response as a potential application and innovation toward new acousto-plasmonic devices.
Recurrence analysis of surface pressure characteristics over symmetrical aerofoil
Authors: Arunvinthan S. , Gopal R. , Chandrasekar V. K. , Nadaraja Pillai S.
Published: January 2020

We study the surface pressure data exhibiting the underlying dynamical behavior of the flow transition over the upper surface of the aerofoil by using recurrence quantification analysis (RQA). In this study, NACA 2415 aerofoil subjected to a turbulent inflow of TI=8.46% at various angles of attack ranging from α=0° to 20° with an increment of 5° corresponding to Re=2.0×105 is considered. We show that the values of recurrence quantification measures effectively distinguish the underlying dynamics of time series surface pressure data at each port, which proves RQA as an effective tool in accurately predicting the flow transitions.
Broadband pumped polarization entangled photon-pair source in a linear beam displacement interferometer
Authors: Lohrmann Alexander , Perumangatt Chithrabhanu , Villar Aitor , Ling Alexander
Published: January 2020

We experimentally demonstrate a source of polarization entangled photon-pairs based on a single periodically poled potassium titanyl phosphate crystal pumped with a broadband, free running laser diode. The crystal is placed within a linear beam-displacement interferometer and emits photon-pairs based on type-0 spontaneous parametric downconversion. We observe pair rates of 0.56 Mpairs/s/mW in a single spatial mode with a polarization visibility of 97.7% over a spectral range of 100 nm. This experiment demonstrates a pathway toward observing gigacount rates of polarization entangled photon pairs by using high-power free-running laser diodes with fast multiplexed detectors.
Non-Ohmic conduction in exfoliated La0.7Ca0.3MnO3 thin films
Authors: Park Jungsik , Shin Jae Hoon , Song Kyung , Kim Yong-Jin , Jang Han-Byul , Lee Hyungwoo , Sim H.-S. , Yang Chan-Ho
Published: January 2020

We present a strong non-Ohmic transport characteristic of the exfoliated La0.7Ca0.3MnO3 thin film obtained by growing a water-soluble sacrificial layer of Sr3Al2O6 between the SrTiO3 substrate and the La0.7Ca0.3MnO3 film. The non-Ohmic conduction manifests itself as a significant amount of electroresistance over a wide range of temperatures. The resistance shows a plateaulike feature at low temperatures, and the electroresistance reaches ∼50 000% at 10 K for input currents varying from 1024 nA to 125 pA. The structural characterization of the exfoliated film reveals the existence of antiphase boundaries, the tunneling through which appears to cause the non-Ohmic feature. Our results provide an avenue into colossal tunneling electroresistance mediated by crystallographic defects.
High tunnel magnetoresistance based on 2D Dirac spin gapless semiconductor VCl3
Authors: Feng Yulin , Wu Xuming , Gao Guoying
Published: January 2020

Future spintronic devices on the nanoscale require low-dimensional materials with high spin polarization. Transition-metal trichlorides have received much attention because 2D ferromagnetism is observed in them such as the ferromagnetic semiconductor of CrI3 monolayer and the ferromagnetic Dirac spin gapless semiconductor of VCl3 monolayer with 100% spin polarization. What about their spin transport properties? Here, we design the magnetic tunnel junction of VCl3/CoBr3/VCl3 with the electrode of the spin gapless semiconductor of VCl3 monolayer and the tunneling barrier of the nonmagnetic semiconductor of CoBr3 monolayer and explore the spin-polarized bias-voltage-dependent tunneling current. Our first-principles calculations combined with nonequilibrium Green's function indicate that VCl3/CoBr3/VCl3 exhibits a high tunnel magnetoresistance ratio (up to 4.5 × 1012%) and a perfect spin filtering effect, which make the VCl3 monolayer useful in 2D spintronic devices. The physical origins of these versatile spin transport properties are discussed in terms of the spin gapless semiconductor property of the VCl3 monolayer and the spin-dependent transmission spectrum.
Shockwave effects on supersonic combustion using hypermixer struts
Authors: Hiejima Toshihiko , Oda Teppei
Published: January 2020

This study describes combustion features due to streamwise vorticity when using hypermixer struts at Mach numbers of 2.5 and 3.5. Two types of struts are used with hydrogen fuel (at an equivalence ratio of 0.4) injected at sonic speed from the trailing edges of the struts. To study the effects of shockwaves on streamwise vorticity formation and supersonic combustion for an alternating-wedge strut, the intersection point at which the shockwaves cross the central axis is varied by changing the length of the strut. When the incident shock is near the trailing edge of the strut, boundary-layer separation occurs on the ramp of the strut due to pressure increase near the strut and subsonic combustion occurs on the basis of this separation. Conversely, when the incident shock is far from the trailing edge of the strut, a streamwise vortex is generated by the strut and supersonic combustion caused by this vortex makes it effective at entraining fuel into itself. Each flame structure obtained here unquestionably differs in its combustion mode. For a separation-resistant strut, the results show that a streamwise vortex with the required circulation can be induced behind the strut without separation. Moreover, the combustion depends strongly on the incident shockwaves in that the combustion efficiency is not subject to the mixing efficiency because the moderate combustion originates near the point at which the formed streamwise vortex interacts with the shockwaves. Therefore, because an ignition point with moderate combustion can detach from its trailing edge, with a separation-resistant strut, it is possible to control the combustion and avoid an excessive heat load.
Laser reflection as a catalyst for direct laser acceleration in multipicosecond laser-plasma interaction
Authors: Weichman K. , Robinson A. P. L. , Beg F. N. , Arefiev A. V.
Published: January 2020

We demonstrate that laser reflection acts as a catalyst for superponderomotive electron production in the preplasma formed by relativistic multipicosecond lasers incident on solid density targets. In 1D particle-in-cell simulations, high energy electron production proceeds via two stages of direct laser acceleration: an initial stochastic backward stage and a final nonstochastic forward stage. The initial stochastic stage, driven by the reflected laser pulse, provides the preacceleration needed to enable the final stage to be nonstochastic. Energy gain in the electrostatic potential, which has been frequently considered to enhance stochastic heating, is only of secondary importance. The mechanism underlying the production of high energy electrons by laser pulses incident on solid density targets is of direct relevance to applications involving multipicosecond laser-plasma interactions.
Cavity ring-down spectroscopy system for the evaluation of negative hydrogen ion density at the ELISE test facility
Authors: Mimo A. , Nakano H. , Wimmer C. , Wünderlich D. , Fantz U. , Tsumori K.
Published: January 2020

The large RF negative hydrogen (deuterium) ion source at the ELISE test facility (half of the ITER-NBI source size) has been equipped with a Cavity Ring-Down Spectroscopy (CRDS) system, in order to measure the negative hydrogen (deuterium) ion density in the region in front of the plasma grid (first grid of the extraction system). The challenge of this diagnostic for ELISE relies on the large size of the source and therefore on the plasma length across which the measurements are performed as well as the long pulses at RF power, which can affect the cavity mirror reliability. A dedicated experiment on the mirror reliability was performed, ensuring the feasibility of measurements for long pulses (several hundred seconds) at high RF power. Two horizontal lines of sight were dedicated to CRDS: the measured density was in the range between 4 × 1016 and 1 × 1017 m−3, with a slightly higher density for the bottom lines of sight, for both the isotope hydrogen and deuterium. Different temporal evolution was observed for the two isotopes, showing a higher instability for the deuterium case: this is in correlation with the extracted negative ion current density and inversely correlated with the coextracted electron current density. The CRDS system allowed performing the first measurements of negative ion density for a long pulse (1000 s) in a large source: the temporal behavior and the effect of the beam extraction will also be discussed.
Many-body collision contributions to electron momentum damping rates in a plasma influenced by electron strong coupling
Authors: Jiang Puchang , Guthrie John , Roberts Jacob L.
Published: January 2020

Experimental studies of electron-ion collision rates in an ultracold neutral plasma can be conducted through measuring the rate of electron plasma oscillation damping. For sufficiently cold and dense conditions where strong coupling influences are important, the measured damping rate was faster by over 30% as compared to theoretical expectations [Chen et al., Phys. Rev. E 96, 013203 (2017)]. We have conducted a series of numerical simulations to isolate the primary source of this difference. By analyzing the distribution of electron velocity changes due to collisions in a molecular dynamics simulation, examining the trajectory of electrons with a high deflection angle in such simulations, and examining the oscillation damping rate while varying the ratio of two-body to three-body electron-ion collision rates, we have found that the difference is consistent with the effect due to many-body collisions that lead to bound electrons. This has implications for other electron-ion collision related transport properties in addition to electron oscillation damping.
Positive and negative hydrogen ion reflections of low-energy atomic and molecular hydrogen ion beam from HOPG and Mo surfaces
Authors: Tanaka Nozomi , Ikemoto Fumiya , Yamada Ippei , Shimabukuro Yuji , Kisaki Masashi , Diño Wilson Agerico , Sasao Mamiko , Wada Motoi , Yamaoka Hitoshi
Published: January 2020

Positive and negative hydrogen ion reflections from surfaces by injecting singly charged hydrogen ion beams show a clear difference between atomic and molecular ion injections at low energy and grazing incidence. The intensity ratio of reflected negative to positive ions H−/H+ increased as the incident beam energy per nucleon decreased only when molecular ion beams are injected. It implies that negative ions are more produced upon beam-surface interaction when molecules are injected. A possible reason was discussed in terms of difference in the negative ion production processes between atomic and molecular ions.
How methane hydrate recovers at very high pressure the hexagonal ice structure
Authors: Schaack S. , Depondt Ph. , Moog M. , Pietrucci F. , Finocchi F.
Published: January 2020

Methane hydrate was recently shown, both experimentally and through simulations, to be stable up to the remarkably high pressure of 150 GPa. A new methane hydrate high-pressure (MH-IV) phase, reminiscent of ice at ambient pressure, was described for pressures above approximately 40 GPa. We disentangle here the main contributions to the relative stability of the lower pressure, denoted MH-III, and the high-pressure MH-IV structures. Through several simulation techniques, including metadynamics and path integral molecular dynamics for nuclear quantum effects, we analyze the phase transition mechanism, which implies hydrogen bond breaking and reforming, as well as methane reordering. The transition pathway is far from trivial, and the quantum delocalization of the hydrogen nuclei plays a significant role.
Strain-engineered room temperature cavity polariton in ZnO whispering gallery microcavity
Authors: Zhu Liqing , Yu Zhaopeng , Sun Liaoxin , Zhou Beier , Dong Hongxing , Zhang Shukui , Wang Jianlu , Zhang Bo , Lin Fangting , Shen Xuechu , Lu Wei
Published: January 2020

Cavity polaritons, originating from the strong coupling effect between cavity modes and excitons, have been tremendously investigated because of their high potential in new or quantum optoelectronic devices. Among them, realization of their dynamic controllability is highly desirable for real applications. In this work, we present a dynamic modulation of cavity polaritons via strain-engineering in the ZnO whispering gallery microcavity. By using a home-made strain apparatus, a nearly uniaxial stress is precisely applied to ZnO microwires, thus inducing an internal strain along its c-axis. Dynamic tuning of cavity polariton modes is clearly characterized by angle-resolved microphotoluminescence spectroscopy. The coupled oscillator's model with fitting parameters of strain-dependent excitons' energies can well describe the modes' redshift. Moreover, we show that the modes' redshift can also be understood by the strain-induced refractive index increase, described by the Lorentz model, of which the underlying mechanism is also related to light-exciton strong coupling. Finally, the strain-engineered dynamic tuning of polariton lasing modes is demonstrated as well, and this actually provides convincing evidence for the polariton states surviving above the threshold. This work indicates that strain-engineered cavity polaritons would pave an alternative way for developing polariton-based integrated or flexible optoelectronic devices.