bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative transcriptomic analysis reveals the roles of ROS scavenging genes in response to cadmium in two pak choi cultivars
Authors: Yu Rugang , Tang Yunshu , Liu Caifeng , Du Xueling , Miao Chunmei , Shi Gangrong
Published: August 2017

To identify key regulatory genes involved in ROS scavenging in response to cadmium (Cd) exposure in pak choi, eight cDNA libraries from Cd-treated and Cd-free roots of two cultivars, Baiyewuyueman (high Cd accumulator) and Kuishan’aijiaoheiye (low Cd accumulator), were firstly performed by RNA-sequencing. Totally 0.443 billion clean reads and 244,190 unigenes were obtained from eight transcriptome. About 797 and 1167 unigenes encoding ROS related proteins and transcription factors were identified. Of them, 11 and 16 ROS scavenging system related DEGs, and 29 and 15 transcription factors related DEGs were found in Baiyewuyueman and Kuishan’aijiaoheiye, respectively. Ten ROS-scavenging genes (Cu/Zn-SOD, GST1, PODs, TrxR2, PrxR, FER3 and NDPK) showed higher expression levels in Cd-exposed seedings of Baiyewuyueman than those of Kuishan’aijiaoheiye. Four genes (GPX, APX, GRX and GST3) specifically expressed in Cd-free roots of Kuishan’aijiaoheiye. For transcription factors, ERF12/13/22 and WRKY31 was up-regulated by Cd in Baiyewuyueman, while in Kuishan’aijiaoheiye, Cd induced down-regulations of bZIP, NAC and ZFP families. The results indicate that the two cultivars differed in the mechanism of ROS scavenging in response to Cd stress. Fe SOD1, POD A2/44/54/62 and GST1 may be responsible for the difference of Cd tolerance between Baiyewuyueman and Kuishan’aijiaoheiye.
RETRACTED ARTICLE: A Chinese herbal formula, Jian-Pi-Yi-Shen
decoction, improves muscle atrophy via regulating mitochondrial quality control
process in 5/6 nephrectomised rats
Authors: Wang Dongtao , Chen Jianping , Liu Xinhui , Zheng Ping , Song Gaofeng , Yi Tiegang , Li Shunmin
Published: August 2017

Muscle atrophy is one of the serious complications of chronic kidney
disease (CKD). Dysregulation of mitochondrial quality control (MQC) process,
including decrease mitochondrial biogenesis, impair mitochondrial dynamics and
induce activation of mitophagy, play an important role in mediating muscle wasting.
This study aimed to observe effects of Jian-Pi-Yi-Shen (JPYS) decoction on muscle
atrophy in CKD rats and explore its possible mechanism on regulation of MQC
processes. The 5/6 nephrectomised rats were randomly allocated into 2 groups: CKD
group and JPYS group. Besides, a sham-operated rats as sham group. All rats were
treated for 6 weeks. Results showed that administration of JPYS decoction prevented
body weight loss, muscle loss, muscle fiber size decrease, muscle protein
degradation, and increased muscle protein systhesis. In addition, JPYS decoction
increased the mitochondrial content and biogenesis proteins, and down-regulated the
autophagy and mitophagy proteins. Furthermore, JPYS decoction increased
mitochondrial fusion proteins, while decreased mitochondrial fission proteins. In
conclusion, JPYS decoction increased mitochondrial content and biogenesis, restore
the balance between fission and fusion, and inhibited autophagy-lysosome pathway
(mitophagy). Collectively, our data showed that JPYS decoction to be beneficial to
muscle atrophy in CKD, which might be associated with the modulation of MQC
process.
In vivo photothermal optical coherence tomography of endogenous and exogenous contrast agents in the eye
Authors: Lapierre-Landry Maryse , Gordon Andrew Y. , Penn John S. , Skala Melissa C.
Published: August 2017

Optical coherence tomography (OCT) has become a standard-of-care in retinal imaging. OCT allows non-invasive imaging of the tissue structure but lacks specificity to contrast agents that could be used for in vivo molecular imaging. Photothermal OCT (PT-OCT) is a functional OCT-based technique that has been developed to detect absorbers in a sample. We demonstrate in vivo PT-OCT in the eye for the first time on both endogenous (melanin) and exogenous (gold nanorods) absorbers. Pigmented mice and albino mice (n = 6 eyes) were used to isolate the photothermal signal from the melanin in the retina. Pigmented mice with laser-induced choroidal neovascularization lesions (n = 7 eyes) were also imaged after a systemic injection of gold nanorods to observe their passive accumulation in the retina. This experiment demonstrates the feasibility of PT-OCT to image the distribution of both endogenous and exogenous absorbers in the mouse retina.
MicroRNA profile for health risk assessment: Environmental exposure to persistent organic pollutants strongly affects the human blood microRNA machinery
Authors: Krauskopf Julian , de Kok Theo M. , Hebels Dennie G. , Bergdahl Ingvar A. , Johansson Anders , Spaeth Florentin , Kiviranta Hannu , Rantakokko Panu , Kyrtopoulos Soterios A. , Kleinjans Jos C.
Published: August 2017

Persistent organic pollutants (POPs) are synthetic chemical substances that accumulate in our environment. POPs such as polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB) and dichlorodiphenyltrichloroethane (DDT) have been classified as carcinogenic to humans and animals. Due to their resistance to biodegradation humans are still exposed to these compounds worldwide. We aim to evaluate the miRNA and transcriptomic response of a human population exposed to POPs. The miRNA and transcriptomic response was measured in blood of healthy subjects by microarray technology and associated with the serum concentrations of six PCB congeners, DDE (a common DDT metabolite), and HCB. A total of 93 miRNA levels appeared significantly associated with the POP-exposure (FDR < 0.05). The miRNA profile includes four tumor suppressor miRNAs, namely miR-193a-3p, miR-152, miR-31-5p and miR-34a-5p. Integration of the miRNA profile with the transcriptome profile suggests an interaction with oncogenes such asMYC,CCND1,BCL2andVEGFA. We have shown that exposure to POPs is associated with human miRNA and transcriptomic responses. The identified miRNAs and target genes are related to various types of cancer and involved in relevant signaling pathways like wnt and p53. Therefore, these miRNAs may have great potential to contribute to biomarker-based environmental health risk assessment.
Key role of higher order symmetry and electrostatic ligand field design in the magnetic relaxation of low-coordinate Er(iii) complexes
Authors: Singh Saurabh Kumar , Pandey Bhawana , Velmurugan Gunasekaran , Rajaraman Gopalan
Published: August 2017

Our theoretical analysis highlights that both symmetry and a suitable ligand field is required to obtain large barrier heights in SIMs. Key role of Lanthanide–halogen covalency in enhancingUeffis discussed.
Control of pH for separated quantitation of nitrite and cyanide ions using photoluminescent copper nanoclusters
Authors: Cang Jinshun , Wang Chia-Wei , Chen Po-Cheng , Lin Yi-Jyun , Li Yu-Chi , Chang Huan-Tsung
Published: August 2017

A dual sensing probe for quantitation of NO2−and CN−ions.
Aggregation-induced emission in precursors to porous molecular crystals
Authors: Zhang Zhenglin , Hashim Mohamed I. , Miljanić Ognjen Š.
Published: August 2017

Trigonal fluorinated pyrazoles assemble into porous molecular crystals and show solid-state fluorescence. However, their emission behavior in solution is dramatically different.
A modular trigger for the development of selective superoxide probes
Authors: Yu Zuo Hang , Chung Clive Yik-Sham , Tang Fung Kit , Brewer Thomas F. , Au-Yeung Ho Yu
Published: August 2017

A biomimetic copper(ii) complex as a selective superoxide trigger for developing a series of multicolor superoxide probes is reported.
Synthetic route to chiral indolines via Cu(OAc)2-catalyzed ring-opening/C(sp2)–H activation of activated aziridines
Authors: Mal Abhijit , Goswami Gaurav , Ahmad Wani Imtiyaz , Ghorai Manas K.
Published: August 2017

A novel synthetic route to functionalized indolinesviaLewis acid catalyzed ring-opening of activated aziridines followed by Cu(OAc)2-mediated intramolecular C–H amination in one-pot with excellent enantio- and diastereospecificity (ee 99%; de >99%).
GeTe: a simple compound blessed with a plethora of properties
Authors: Boschker Jos E. , Wang Ruining , Calarco Raffaella
Published: August 2017

A selection from the wide range of functional properties present in the binary compound, GeTe, are reviewed is this paper.
Selective adsorption behaviour of carbon dioxide in OH-functionalized metal–organic framework materials
Authors: Qian Jinjie , Shen Jinni , Li Qipeng , Hu Yue , Huang Shaoming
Published: August 2017

The theoretically optimal adsorption locations in hydroxyl (OH)-decorated metal–organic frameworks show that the captured CO2 molecules interact with the cis-μ2-OH groups in an end-on mode, which shows a moderate to weak hydrogen bond.
Tridentate C–I⋯O−–N+ halogen bonds
Authors: Topić Filip , Puttreddy Rakesh , Rautiainen J. Mikko , Tuononen Heikki M. , Rissanen Kari
Published: August 2017

N-Oxides can act as tridentate halogen bond acceptors, or as tetradentate ligands in a pseudo-μ4 mode with silver(i).
Gradient-free determination of isoelectric points of proteins on chip
Authors: Łapińska Urszula , Saar Kadi L. , Yates Emma V. , Herling Therese W. , Müller Thomas , Challa Pavan K. , Dobson Christopher M. , Knowles Tuomas P. J.
Published: August 2017

We have developed a method for measuring protein isoelectric points on a microfluidic chip in which gradient changes in time rather then in space.
The generalized maximum hardness principle revisited and applied to atoms and molecules
Authors: Grochala Wojciech
Published: August 2017

Part 1 of this duology is devoted to isolated atoms and molecules, and to chemical reactions between them; we introduce here basic concepts beyond the Generalized Maximum Hardness Principle, and the corresponding Minimum Polarizability Principle, and we illustrate applicability of both principles to a broad range of chemical phenomena and distinct systems in the gas phase.
Complexation induced aggregation and deaggregation of acridine orange with sulfobutylether-β-cyclodextrin
Authors: Sayed Mhejabeen , Jha Shruti , Pal Haridas
Published: August 2017

The present study illustrates intriguing switching of multi-mode binding interactions of acridine orange dye with a sulfobutylether-β-cyclodextrin host.
Cross-sectional structures of a molecular monolayer nanotube explored with SAXS: evidence for the parallel orientation of the headgroups in asymmetric bolaamphiphiles
Authors: Yoshida Kenta , Takahashi Rintaro , Fujii Shota , Kameta Naohiro , Shimizu Toshimi , Sakurai Kazuo
Published: August 2017

We investigated the cross-sectional structure of a molecular monolayer nanotube self-assembled from asymmetric bolaamphiphiles having two different hydrophilic headgroups.
The frequency-dependent AC photoresistance behavior of ZnO thin films grown on different sapphire substrates
Authors: Cholula-Díaz Jorge L. , Barzola-Quiquia José , Videa Marcelo , Yin Chunhai , Esquinazi Pablo
Published: August 2017

This work reports an unusual positive photoresistance effect observed in ZnO thin films using impedance spectroscopy.
Differential capacitance of an electric double layer with asymmetric solvent-mediated interactions: mean-field theory and Monte Carlo simulations
Authors: Caetano Daniel L. Z. , Bossa Guilherme V. , de Oliveira Vinicius M. , Brown Matthew A. , de Carvalho Sidney J. , May Sylvio
Published: August 2017

The differential capacitance of an electrical double layer is directly affected by properties of the electrolyte solution such as temperature, salt concentration, ionic size, and solvent structure.
On the mobility of carriers at semi-coherent oxide heterointerfaces
Authors: Dholabhai Pratik P. , Martínez Enrique , Brown Nicholas T. , Uberuaga Blas Pedro
Published: August 2017

KMC simulations reveal the kinetic behavior of oxygen vacancies at semi-coherent oxide heterointerfaces.
MANOTA: a promising bifunctional chelating agent for copper-64 immunoPET
Authors: Moreau M. , Poty S. , Vrigneaud J.-M. , Walker P. , Guillemin M. , Raguin O. , Oudot A. , Bernhard C. , Goze C. , Boschetti F. , Collin B. , Brunotte F. , Denat F.
Published: August 2017

A comparison of four bifunctional chelating agents showed superior behaviour of a new NOTA derivative for 64Cu labelling of antibody fragments.
Molybdenum modified nickel phyllosilicates as a high performance bifunctional catalyst for deoxygenation of methyl palmitate to alkanes under mild conditions
Authors: Yan Long , Liu Xinxin , Deng Jin , Fu Yao
Published: August 2017

A new Mo doping Ni phyllosilicates catalyst (Mo–Ni@PSi) was synthesized and exhibited high catalytic activity under mild reaction condition for the deoxygenation of methyl palmitate.
Tumour-vessel-on-a-chip models for drug delivery
Authors: Caballero David , Blackburn Sophie M. , de Pablo Mar , Samitier Josep , Albertazzi Lorenzo
Published: August 2017

In this review, we present the use of tumour-vessels-on-a-chip to investigate and screen nanoparticles for cancer targeted drug delivery.
Endohedral pnicogen and triel bonds in doped C60fullerenes
Authors: Mohajeri Afshan , Eskandari K. , Amin Safaee Saeedeh
Published: August 2017

Encapsulation of HnYF3−nin C30X15Y15(X = B, Al and Y = N, P andn= 1, 2) and characterization of the endohedral pnicogen and triel bonds.
Development of pyridine based o-aminophenolate zinc complexes as structurally tunable catalysts for CO2 fixation into cyclic carbonates
Authors: Alaji Z. , Safaei E. , Wojtczak A.
Published: August 2017

Structure–reactivity correlation in o-aminophenolate zinc catalysts provides an atom-efficient protocol for the conversion of CO2 into valuable cyclic carbonates.
Synthesis, characterization, computational and antimicrobial activities of a novel iridium thiourea complex
Authors: Kumar S. , Purcell W. , Conradie J. , Bragg R. R. , Langner E. H. G.
Published: August 2017

A novel octahedral iridium(iii)thiourea complex with potential medical applications.
A graphene quantum dot-assisted morin–KMnO4 chemiluminescence system for the precise recognition of cypermethrin
Authors: Khataee Alireza , Hassanzadeh Javad , Lotfi Roya
Published: August 2017

A novel and efficient chemiluminescence (CL) probe was developed for cypermethrin (CYPM) based on the sensitizing effect of graphene quantum dots (GQDs) on the morin–KMnO4 CL reaction.
Resonant silicon nanoparticles for enhancement of light absorption and photoluminescence from hybrid perovskite films and metasurfaces
Authors: Tiguntseva E. , Chebykin A. , Ishteev A. , Haroldson R. , Balachandran B. , Ushakova E. , Komissarenko F. , Wang H. , Milichko V. , Tsypkin A. , Zuev D. , Hu W. , Makarov S. , Zakhidov A.
Published: August 2017

Silicon nanoparticles with Mie resonances on hybrid perovskite films and metasurfaces allow for increase of absorption and photoluminescence.
A versatile upconversion surface evaluation platform for bio–nano surface selection for the nervous system
Authors: Fu Libing , Morsch Marco , Shi Bingyang , Wang Guoying , Lee Albert , Radford Rowan , Lu Yiqing , Jin Dayong , Chung Roger
Published: August 2017

There is considerable interest in developing diagnostic nanotools for early detection and delivery of various therapeutic agents for treatment of neurodegenerative diseases.
Efficient and long-lifetime full-color light-emitting diodes using high luminescence quantum yield thick-shell quantum dots
Authors: Shen Huaibin , Lin Qingli , Cao Weiran , Yang Chenchen , Shewmon Nathan T. , Wang Hongzhe , Niu Jinzhong , Li Lin Song , Xue Jiangeng
Published: August 2017

Peak external quantum efficiencies (EQEs) of 10.2%, 15.4%, and 15.6% were achieved for red, green, and blue QLEDs, respectively, by using high quantum yield thick-shell QDs.
Molecular simulations of peptide amphiphiles
Authors: Manandhar Anjela , Kang Myungshim , Chakraborty Kaushik , Tang Phu K. , Loverde Sharon M.
Published: August 2017

This review describes recent progress in the area of molecular simulations of peptide assemblies, including peptide-amphiphiles, and drug-amphiphiles.
Carboxylate isosteres for caspase inhibitors: the acylsulfonamide case revisited
Authors: Adriaenssens Y. , Jiménez Fernández D. , Vande Walle L. , Elvas F. , Joossens J. , Lambeir A. , Augustyns K. , Lamkanfi M. , Van der Veken P.
Published: August 2017

Acylsulfonamides are efficient carboxylate isosteres for caspase inhibitors. In inhibitors with an aldehyde warhead, they serve as prodrug-type precursors of the carboxylate-containing compounds.
Cu(0)-RDRP of methacrylates in DMSO: importance of the initiator
Authors: Jones Glen R. , Whitfield Richard , Anastasaki Athina , Risangud Nuttapol , Simula Alexandre , Keddie Daniel J. , Haddleton David M.
Published: August 2017

The controlled radical polymerization of methacrylates via Cu(0)-mediated RDRP is challenging in comparison to acrylates with most reports illustrating higher dispersities, lower monomer conversions and poorer end group fidelity relative to the acrylic analogues.
Synthesis of thiophosphates through a three-component reaction by using sulfur dioxide as the sulfur source
Authors: Gong Xinxing , Chen Jiahao , Liu Jianhe , Wu Jie
Published: August 2017

Generation of thiophosphates through a three-component reaction of diaryliodonium tetrafluoroborates, 1,4-diazabicyclo[2.2.2]octane-sulfur dioxide (DABCO·(SO2)2), and diarylphosphine oxides under visible light irradiation is described.
Biological phosphorylated molecules participate in the biomimetic and biological synthesis of cadmium sulphide quantum dots by promoting H2S release from cellular thiols
Authors: Venegas F. A. , Saona L. A. , Monrás J. P. , Órdenes-Aenishanslins N. , Giordana M. F. , Ulloa G. , Collao B. , Bravo D. , Pérez-Donoso J. M.
Published: August 2017

Developing methods with a low environmental impact for nanoparticle synthesis remains one of the greatest challenges in nanotechnology.
Activity of IrO2 supported on tantalum-doped TiO2 electrocatalyst for solid polymer electrolyte water electrolyzer
Authors: Lv Hong , Zhang Guanghui , Hao Chuanpu , Mi Cangen , Zhou Wei , Yang Daijun , Li Bing , Zhang Cunman
Published: August 2017

TiO2 doped tantalum was successfully synthesized via an evaporation-induced self-assembly method as a support of IrO2 for a SPE water electrolyzer. The 80% IrO2/Ti0.7Ta0.3O2 showed the best performance with the potential of 1.849 V at 1000 mA cm−2.
Characteristics of rumen microorganisms involved in anaerobic degradation of cellulose at various pH values
Authors: Zhang Lu , Chung Jongshik , Jiang Qingqing , Sun Rui , Zhang Jian , Zhong Yingjuan , Ren Nanqi
Published: August 2017

Microbial degradation of straw, the main by-product of agricultural production, has proved to be the most economical and effective means of producing hydrogen.
A new design for an artificial cell: polymer microcapsules with addressable inner compartments that can harbor biomolecules, colloids or microbial species
Authors: Lu Annie Xi , Oh Hyuntaek , Terrell Jessica L. , Bentley William E. , Raghavan Srinivasa R.
Published: August 2017

Multicompartment capsules with control over the contents of each inner compartment are prepared by a simple, oil-free technique.
Highly efficient blue phosphorescent iridium(iii) complexes with various ancillary ligands for partially solution-processed organic light-emitting diodes
Authors: Tao Peng , Zhang Yuanbing , Wang Jiong , Wei Liuwei , Li Hongxin , Li Xiangling , Zhao Qiang , Zhang Xinwen , Liu Shujuan , Wang Hua , Huang Wei
Published: August 2017

Excellent blue/pure blue iridium(iii) phosphors with high ΦPL, narrow FWHMs and robust chemical structures are designed for partially solution-processed OLEDs.
Inverse synthetic aperture ladar imaging with stepped‐frequency continuous waveform
Authors: Li Guangzuo , Wang Ning , Mo Di , Wang Ran , Zhang Zenghui , Wu Yirong
Published: August 2017

Inverse synthetic aperture ladar (ISAL) is analogous to the inverse synthetic aperture radar but works at frequency 104–5 times higher. A method is proposed to process the ISAL data with stepped‐frequency continuous waveform (SFCW). Due to the short wavelength used for ISAL and the relatively long transmission of the SFCW, the motion during the transmission and the relative range shift between adjacent sub‐band chirps must be both taken into account while performing the bandwidth synthesis and imaging. An analytic signal model was derived to address this problem. In the proposed model, three additional terms, named the bulk range walk term, the stepped phase error term and the additional range shift, were formulated in ISAL imaging with SFCW for the first time. Based on the signal model, an effective method was proposed to coherently synthesise all the sub‐band echoes and then focus the ISAL image. Experimental result was shown and the focused image of an airplane model demonstrated the effectiveness of the proposed method.
Can surgical simulation be used to train detection and classification of neural networks?
Authors: Zisimopoulos Odysseas , Flouty Evangello , Stacey Mark , Muscroft Sam , Giataganas Petros , Nehme Jean , Chow Andre , Stoyanov Danail
Published: August 2017

Computer‐assisted interventions (CAI) aim to increase the effectiveness, precision and repeatability of procedures to improve surgical outcomes. The presence and motion of surgical tools is a key information input for CAI surgical phase recognition algorithms. Vision‐based tool detection and recognition approaches are an attractive solution and can be designed to take advantage of the powerful deep learning paradigm that is rapidly advancing image recognition and classification. The challenge for such algorithms is the availability and quality of labelled data used for training. In this Letter, surgical simulation is used to train tool detection and segmentation based on deep convolutional neural networks and generative adversarial networks. The authors experiment with two network architectures for image segmentation in tool classes commonly encountered during cataract surgery. A commercially‐available simulator is used to create a simulated cataract dataset for training models prior to performing transfer learning on real surgical data. To the best of authors’ knowledge, this is the first attempt to train deep learning models for surgical instrument detection on simulated data while demonstrating promising results to generalise on real data. Results indicate that simulated data does have some potential for training advanced classification methods for CAI systems.
Evaluation of shadow features
Authors: Qu Liangqiong , Tian Jiandong , Fan Huijie , Li Wentao , Tang Yandong
Published: August 2017

Shadow features such as colour ratio, texture, and chromaticity have proved to be quite effective in shadow detection. Many shadow detection methods have been proposed on the basis of different features. However, previous works for shadow detection mainly focus on designing an effective classifier for existing shadow features, but pay less attention on the analysis of shadow features themselves. The majority of studies simply report the final shadow detection results rather than make an evaluation on each feature. Readers often do not know which features are more effective or whether these shadow features are complementary. The following problems are still unsolved: the robustness of each feature, which feature plays the most important role in a detection method, and what is the best performance that current features can reach. The purpose of this study is to answer these questions, and the authors hope that this study can offer guidance for future shadow detection algorithms via the evaluation of frequently used shadow features. Several useful and interesting conclusions are obtained after conducting extensive comparison experiments on a large dataset.
Dual‐band filter with fully independent passbands based on unequal‐length coupled lines and stubs
Authors: Ha Jungje , Lee Yongshik
Published: August 2017

In this work, a dual‐band filter that has completely independent passbands is demonstrated. The complete independence of the two passbands is achieved by simultaneously abandoning the classical restriction on electrical lengths for dual‐band operation and allowing all the components to have different lengths. As a result, the proposed filter has different sets of J‐inverter values and susceptance slope parameters independently at two centre frequencies. Therefore, the two passbands can be designed to have not only different bandwidths, but also different passband responses simultaneously; i.e. one passband can be designed to be a Chebyshev type while the other is a Butterworth type, or a Chebyshev type with different passband ripple levels. Rigorous design equations are derived and various design curves are provided to discuss the practicality of the proposed method. Finally, two filters with different bandwidths and passband types are demonstrated experimentally. The excellent agreement between the simulated and measured results verifies the practicality of the proposed method.
Extended orthogonal matching pursuit for robust and fast target localisation in multiple‐input multiple‐output radar
Authors: Cattenoz Mathieu , Savy Laurent , Marcos Sylvie
Published: August 2017

The multiple‐input multiple‐output (MIMO) radar combines ultra‐wide angular illumination on transmit and narrow transmission angular resolution after processing on receive. Orthogonal waveforms are needed in theory for all independent transmitters, but this property is usually not achievable in practice, therefore leading to a degraded ambiguity function. In this study, the authors focus on phase codes waveform, which gives quasi‐optimal angle and range resolution. On the other hand, they induce a harmful ‘floor’ of high‐level sidelobes in the range–angle domain. The authors propose to apply the orthogonal matching pursuit (OMP) to the MIMO radar signals. Therefore, it becomes theoretically possible to detect targets initially hidden by high‐level sidelobes. Nevertheless, the authors identify phenomenon (grid granularity, neighbour influence) that lead to possible localisation error resulting in ghost targets. Considering this, the authors propose an extension of the OMP rejection step that includes, in addition to the expected target position, the neighbour positions within the uncertainty area. The authors show that this extension allows them to suppress the sensibility of the OMP to localisation error, even in case of very close targets. Finally, the authors demonstrate the performance of the proposed method on simulations as well as on experimental MIMO radar signals.
Near‐field multistatic radar reconstruction with stretched‐phase Fourier accelerated multistatic imaging
Authors: Marks Daniel L. , Yurduseven Okan , Smith David R.
Published: August 2017

There exist few rapid reconstruction methods for applications that use multistatic radar for targets in the near field such as vehicle navigation and personnel screening. Fourier accelerated multistatic imaging (FAMI) is a method that combines the rapid reconstruction speed of Fourier‐based imaging algorithms with the flexibility of algebraic algorithms that allow arbitrary radiation patterns and antenna placement. Many of these new applications image in the near field of the individual antennas of a multistatic array, however, FAMI contains approximations that require the target to be in the far field of each antenna. Stretched‐phase FAMI (SP‐FAMI) overcomes this limitation and allows imaging in the Fresnel region of the antennas so that targets may be very close to the array while retaining the computational benefits of Fourier reconstruction. As radar wavelengths decrease with a corresponding increase in resolution, SP‐FAMI allows the imaging of nearby targets that would otherwise be too close for FAMI to image accurately.
Superconducting magnetic energy storage and superconducting self-supplied electromagnetic launcher
Authors: Ciceron Jérémie , Badel Arnaud , Tixador Pascal
Published: August 2017

Superconductors can be used to build energy storage systems called Superconducting Magnetic Energy Storage (SMES), which are promising as inductive pulse power source and suitable for powering electromagnetic launchers. The second generation of high critical temperature superconductors is called coated conductors or REBCO (Rare Earth Barium Copper Oxide) tapes. Their current carrying capability in high magnetic field and their thermal stability are expanding the SMES application field. The BOSSE (Bobine Supraconductrice pour le Stockage d’Energie) project aims to develop and to master the use of these superconducting tapes through two prototypes. The first one is a SMES with high energy density. Thanks to the performances of REBCO tapes, the volume energy and specific energy of existing SMES systems can be surpassed. A study has been undertaken to make the best use of the REBCO tapes and to determine the most adapted topology in order to reach our objective, which is to beat the world record of mass energy density for a superconducting coil. This objective is conflicting with the classical strategies of superconducting coil protection. A different protection approach is proposed. The second prototype of the BOSSE project is a small-scale demonstrator of a Superconducting Self-Supplied Electromagnetic Launcher (S3EL), in which a SMES is integrated around the launcher which benefits from the generated magnetic field to increase the thrust applied to the projectile. The S3EL principle and its design are presented.
N-Arylation of Heterocycles by a Tandem Aza-Michael Addition Reaction and Aromatization Sequence
Authors: Chittimalla Santhosh , Nakka Srinuvasu , Koodalingam Manikandan , Bandi Chennakesavulu
Published: August 2017

Cyclohexa-2,4-dien-1-one derivatives, upon reaction with N-heterocycles in the presence of scandium(III) triflate, underwent a tandem Michael addition reaction followed by aromatization of the ­Michael adduct generated in situ to give N-aryl heterocycles in good yields. Because of the ready accessibility of variously substituted cyclohexa-2,4-dien-1-ones, a range of N-aryl heterocycles have become available.
Chemistry 2.0: Developing a New, Solvent-Free System of Chemical Synthesis Based on Mechanochemistry
Authors: Friščić Tomislav , Do Jean-Louis
Published: August 2017

Mechanochemistry by grinding or milling has grown from a laboratory curiosity to a versatile approach for the synthesis and discovery of molecules, materials and reactivity. Focusing on organic synthesis and the chemistry of organic solids in general, we now provide a snapshot of this exciting, rapidly developing area, with the intention to illustrate its potential in establishing a more efficient and environmentally friendly system of chemical and materials synthesis, based on solid-state transformations rather than conventional, solution-dependent chemistry.

1 What is Chemistry 2.0?

2 Introduction

2.1 Why Mechanochemistry Now?

2.2 What’s in a Mechanochemistry Laboratory?

3 Liquid-Assisted Grinding (LAG): Controlling Mechanochemistry

4 The Solvent-Free Research Laboratory

5 Medicinal Mechanochemistry

6 Exploring Molecular Recognition

7 Some Myths to Dispel

8 Catalytic Reactions by Mechanochemistry

8.1 Catalysis and Reactivity Involving Bulk Metals

8.2 Enzyme Catalysis in Mechanochemistry

8.3 Coupling of Mechanochemistry, Photochemistry and Supramolecular Catalysis

9 Organometallic Mechanochemistry

10 New Opportunities

10.1 Stoichiometric Control

10.2 ‘Impossible’ Molecules

10.3 Reaction Discovery by Mechanochemistry

11 Energetics of Mechanochemistry

12 Mechanistic Understanding

13 Real-Time Reaction Monitoring

14 Conclusions
Tracking On-Surface Chemistry with Atomic Precision
Authors: Jacobse Peter , Moret Marc-Etienne , Klein Gebbink Robertus , Swart Ingmar
Published: August 2017

The field of on-surface synthesis has seen a tremendous development in the past decade as an exciting new methodology towards atomically well-defined nanostructures. A strong driving force in this respect is its inherent compatibility with scanning probe techniques, which allows one to ‘view’ the reactants and products at the single-molecule level. In this article, we review the ability of noncontact atomic force microscopy to study on-surface chemical reactions with atomic precision. We highlight recent advances in using noncontact atomic force microscopy to obtain mechanistic insight into reactions and focus on the recently elaborated mechanisms in the formation of different types of graphene nanoribbons.
An approach to the interpretation of Cole–Davidson and Cole–Cole dielectric functions
Authors: Iglesias T. P. , Vilão G. , Reis João Carlos R.
Published: August 2017

Assuming that a dielectric sample can be described by Debye's model at each frequency, a method based on Cole's treatment is proposed for the direct estimation at experimental frequencies of relaxation times and the corresponding static and infinite-frequency permittivities. These quantities and the link between dielectric strength and mean molecular dipole moment at each frequency could be useful to analyze dielectric relaxation processes. The method is applied to samples that follow a Cole–Cole or a Cole–Davidson dielectric function. A physical interpretation of these dielectric functions is proposed. The behavior of relaxation time with frequency can be distinguished between the two dielectric functions. The proposed method can also be applied to samples following a Navriliak–Negami or any other dielectric function. The dielectric relaxation of a nanofluid consisting of graphene nanoparticles dispersed in the oil squalane is reported and discussed within the novel framework.
Spin accumulation in disordered topological insulator ultrathin films
Authors: Siu Zhuo Bin , Ho Cong Son , Tan Seng Ghee , Jalil Mansoor B. A.
Published: August 2017

Topological insulator (TI) ultrathin films differ from the more commonly studied semi-infinite bulk TIs in that the former possess both top and bottom surfaces where the surface states localized at different surfaces can couple to one another across the finite thickness of the film. In the presence of an in-plane magnetization, the TI thin films display two distinct phases depending on which of the inter-surface coupling or the magnetization is stronger. In this work, we consider a Bi2Se3 TI thin film system with an in-plane magnetization and numerically calculate the resulting spin accumulation on both surfaces of the film due to an in-plane electric field to linear order. We describe a numerical scheme for performing the Kubo formula calculation in which we include impurity scattering and vertex corrections. We find that the sums of the spin accumulation over the two surfaces in the in-plane direction perpendicular to the magnetization and in the out of plane direction are antisymmetric in Fermi energy around the charge neutrality point and are non-vanishing only when the symmetry between the top and bottom TI surfaces is broken. The impurity scattering, in general, diminishes the magnitude of the spin accumulation.
Lattice thermal expansion and anisotropic displacements in urea, bromomalonic aldehyde, pentachloropyridine, and naphthalene
Authors: George Janine , Wang Ruimin , Englert Ulli , Dronskowski Richard
Published: August 2017

Anisotropic displacement parameters (ADPs) are commonly used in crystallography, chemistry, and related fields to describe and quantify thermal motion of atoms. Within the very recent years, these ADPs have become predictable by lattice dynamics in combination with first-principles theory. Here, we study four very different molecular crystals, namely, urea, bromomalonic aldehyde, pentachloropyridine, and naphthalene, by first-principles theory to assess the quality of ADPs calculated in the quasi-harmonic approximation. In addition, we predict both the thermal expansion and thermal motion within the quasi-harmonic approximation and compare the predictions with the experimental data. Very reliable ADPs are calculated within the quasi-harmonic approximation for all four cases up to at least 200 K, and they turn out to be in better agreement with the experiment than those calculated within the harmonic approximation. In one particular case, ADPs can even reliably be predicted up to room temperature. Our results also hint at the importance of normal-mode anharmonicity in the calculation of ADPs.
Liquid-like behaviour of gold nanowire bridges
Authors: Naik Jay P. , Cheneler David , Bowen James , Prewett Philip D.
Published: August 2017

A combination of Focused Ion Beam and Reactive Ion Etch was used to fabricate free standing gold nanowire bridges with radii of 30 nm and below. These were subjected to point loading to failure at their mid-points using an atomic force microscope, providing strength and deformation data. The results demonstrate a dimensionally dependent transition from conventional solid metallic properties to liquid-like behaviour including the unexpected reformation of a fractured bridge. The work reveals mechanical and materials properties of nanowires which could have significant impact on nanofabrication processes and nanotechnology devices such as Nano Electro Mechanical Systems.
Fast switching and signature of efficient domain wall motion driven by spin-orbit torques in a perpendicular anisotropy magnetic insulator/Pt bilayer
Authors: Avci Can Onur , Rosenberg Ethan , Baumgartner Manuel , Beran Lukáš , Quindeau Andy , Gambardella Pietro , Ross Caroline A. , Beach Geoffrey S. D.
Published: August 2017

We report fast and efficient current-induced switching of a perpendicular anisotropy magnetic insulator thulium iron garnet by using spin-orbit torques (SOT) from the Pt overlayer. We first show that, with quasi-DC (10 ms) current pulses, SOT-induced switching can be achieved with an external field as low as 2 Oe, making TmIG an outstanding candidate to realize efficient switching in heterostructures that produce moderate stray fields without requiring an external field. We then demonstrate deterministic switching with fast current pulses (≤20 ns) with an amplitude of ∼1012 A/m2, similar to all-metallic structures. We reveal that, in the presence of an initially nucleated domain, the critical switching current is reduced by up to a factor of five with respect to the fully saturated initial state, implying efficient current-driven domain wall motion in this system. Based on measurements with 2 ns-long pulses, we estimate the domain wall velocity of the order of ∼400 m/s per j = 1012 A/m2.
Uniform lifetime prolongation of a high density plasma channel left in the wake of femtosecond filament
Authors: Papeer J. , Dey I. , Henis Z. , Botton M. , Ferber Y. , Kumar G. R. , Zigler A.
Published: August 2017

We demonstrate uniform lifetime prolongation of an entire plasma filament generated by a high-power femtosecond laser pulse. The entire filament is irradiated by a secondary nano-second laser pulse that co-propagates with the femtosecond laser. The plasma filament partially absorbs the nanosecond laser radiation, and plasma lifetime is extended along the entire channel resulting in a smooth and continuous high-density plasma column with lifetime longer than 30 ns. We present an experimental and theoretical study of the intensity range of the secondary laser required for effective lifetime prolongation and the behavior of the plasma density at the onset of breakdown triggered by the secondary laser. Our study shows that an efficient prolongation of the lifetime of plasma filament occurs in the intensity range of 0.03–0.3 TW/cm2.
Mass diffusion cloaking and focusing with metamaterials
Authors: Restrepo-Flórez Juan Manuel , Maldovan Martin
Published: August 2017

Recent advances in the design of metamaterials that control diffusive transport processes have enabled efficient devices to manipulate heat conduction. In contrast, control of mass diffusion with metamaterial devices has been largely unexplored. Mass diffusion is critically important in multiple research areas ranging from electronic and energy materials to chemical and biological systems. In this work, we introduce a physical approach to design mass diffusion metamaterial devices that take into account the fundamental physical mechanisms behind mass transport. We demonstrate that mass concentration discontinuities arising from different material solubilities are critical physical factors that need to be incorporated for the accurate design and characterization of mass diffusion metamaterial devices. We employ our approach to devise and analyze cloaking and focusing of molecules and show how the difference in solubilities is critically important for the efficiency of the metamaterials. This work provides physical insights and guidelines to understand and design mass diffusion in metamaterial devices.
Novel diamond cells for neutron diffraction using multi-carat CVD anvils
Authors: Boehler R. , Molaison J. J. , Haberl B.
Published: August 2017

Traditionally, neutron diffraction at high pressure has been severely limited in pressure because low neutron flux required large sample volumes and therefore large volume presses. At the high-flux Spallation Neutron Source at the Oak Ridge National Laboratory, we have developed new, large-volume diamond anvil cells for neutron diffraction. The main features of these cells are multi-carat, single crystal chemical vapor deposition diamonds, very large diffraction apertures, and gas membranes to accommodate pressure stability, especially upon cooling. A new cell has been tested for diffraction up to 40 GPa with an unprecedented sample volume of ∼0.15 mm3. High quality spectra were obtained in 1 h for crystalline Ni and in ∼8 h for disordered glassy carbon. These new techniques will open the way for routine megabar neutron diffraction experiments.
High-Q plasmonic infrared absorber for sensing of molecular resonances in hybrid lead halide perovskites
Authors: Dayal Govind , Solanki Ankur , Chin Xin Yu , Sum Tze Chien , Soci Cesare , Singh Ranjan
Published: August 2017

Plasmonic resonances in sub-wavelength metal-dielectric-metal cavities have been shown to exhibit strong optical field enhancement. The large field enhancements that occur in sub-wavelength regions of the cavity can drastically boost the performance of microcavity based detectors, electromagnetic wave absorbers, metasurface hologram, and nonlinear response of the material in a cavity. The performance efficiencies of these plasmonic devices can be further improved by designing tunable narrow-band high-Q cavities. Here, we experimentally and numerically demonstrate high-Q resonances in metal-dielectric-metal cavity consisting of an array of conductively coupled annular and rectangular apertures separated from the bottom continuous metal film by a thin dielectric spacer. Both, the in-plane and out of plane coupling between the resonators and the continuous metal film have been shown to support fundamental and higher order plasmonic resonances which result in high-Q response at mid-infrared frequencies. As a sensor application of the high-Q cavity, we sense the vibrational resonances of an ultrathin layer of solution-processed organic–inorganic hybrid lead halide perovskites.
Force-free collisionless current sheet models with non-uniform temperature and density profiles
Authors: Wilson F. , Neukirch T. , Allanson O.
Published: August 2017

We present a class of one-dimensional, strictly neutral, Vlasov-Maxwell equilibrium distribution functions for force-free current sheets, with magnetic fields defined in terms of Jacobian elliptic functions, extending the results of Abraham-Shrauner [Phys. Plasmas 20, 102117 (2013)] to allow for non-uniform density and temperature profiles. To achieve this, we use an approach previously applied to the force-free Harris sheet by Kolotkov et al. [Phys. Plasmas 22, 112902 (2015)]. In one limit of the parameters, we recover the model of Kolotkov et al. [Phys. Plasmas 22, 112902 (2015)], while another limit gives a linear force-free field. We discuss conditions on the parameters such that the distribution functions are always positive and give expressions for the pressure, density, temperature, and bulk-flow velocities of the equilibrium, discussing the differences from previous models. We also present some illustrative plots of the distribution function in velocity space.
Modified electron beam induced current technique for in(Ga)As/InAsSb superlattice infrared detectors
Authors: Yoon N. , Reyner C. J. , Ariyawansa G. , Duran J. M. , Scheihing J. E. , Mabon J. , Wasserman D.
Published: August 2017

Electron beam induced current (EBIC) measurements provide a powerful tool for characterizing semiconductor based materials and devices. By measuring the current generated by the electron beam of a scanning electron microscope (SEM), EBIC allows us to extract the minority carrier diffusion length (L) and the surface recombination velocity to diffusivity ratio (S/D) of a material. When combined with information on minority carrier lifetime (τ), for instance from time-resolved photoluminescence measurements, the minority carrier mobility of the material can be extracted. However, the EBIC technique relies heavily on the accurate modeling of the carrier generation and collection process. Traditionally, this was achieved using a combination of empirical analytical expressions (and later Monte Carlo simulations) for carrier generation and analytical diffusion/recombination expressions for carrier collection. This approach introduces significant uncertainties into the extracted material parameters. Here, we present a numerical approach to EBIC modeling which improves the spatial resolution of our model, while also retaining information regarding the relative EBIC signal as a function of incident beam energies and currents. We apply this technique to investigate the temperature dependent minority carrier mobility of InAs/InAsSb and InGaAs/InAsSb strained layer superlattice infrared detectors and compare our results to the values obtained using external quantum efficiency measurements of the same samples. Our approach not only allows for an improvement in the uncertainty of the extracted material parameters, but also offers insight into the material and device behavior as a function of nonequilibrium carrier concentration. The technique presented here offers potentially improved characterization of not only infrared detectors, but a range of semiconductor-based devices.
Simulation of mechanical performance of nanoporous FCC copper under compression with pores mimicking several crystalline arrays
Authors: Cui Yi , Chen Zengtao
Published: August 2017

The mechanical performance of porous metal with assembly of pores mimicking typical crystalline structures is studied via atomistic simulation and finite element method. The pore lattices are made with the same orientation as the face-centered cubic (FCC) copper lattice. The compression is applied in the [0 0 1] direction. Under the same initial porosity and identical pore size, pores assembled in diamond array result in a superior stress response under compression. The sample with pores assembled in body-centered cubic array, whose surface-to-volume ratio is close to that of either FCC or hexagonally close-packed (HCP) array, has a yet much higher yield stress. However, the FCC- and HCP-structured nanoporous samples exhibit a greater hardening effect. The Lubarda model for critical stress to trigger dislocation emission is extended to the nanoporous geometry numerically. The magnitude and distribution of shear stress on the slip plane are found crucial to dislocation activities. No strong correlation between dislocation formation and early densification of nanoporous geometry is found. Through comparing the yielding and hardening behavior among differently structured nanoporous samples, new understanding could be established on their mechanical performance. Enhanced structural integrity could better support their diverse applications by design.