bluuebunny/crossref_metadata_2025 huggingface dataset:
The Ground State of Monolayer Graphene in a Strong Magnetic Field
Authors: Wu Lian-Ao , Guidry Mike
Published: March 2016

Experiments indicate that the ground state of graphene in a strong magnetic field exhibits spontaneous breaking of SU(4) symmetry. However, the nature of the corresponding emergent state is unclear because existing theoretical methods approximate the broken-symmetry solutions, yielding nearly-degenerate candidate ground states having different emergent orders. Resolving this ambiguity in the nature of the strong-field ground state is highly desirable, given the importance of graphene for both fundamental physics and technical applications. We have discovered a new SO(8) symmetry that recovers standard graphene SU(4) quantum Hall physics, but predicts two new broken-SU(4) phases and new properties for potential ground states. Our solutions are analytical; thus we capture the essential physics of spontaneously-broken SU(4) states in a powerful yet solvable model useful both in correlating existing data and in suggesting new experiments.
Identification of Loci Modulating the Cardiovascular and Skeletal Phenotypes of Marfan Syndrome in Mice
Authors: Fernandes Gustavo R. , Massironi Silvia M. G. , Pereira Lygia V.
Published: March 2016

Marfan syndrome (MFS) is an autosomal dominant disease of the connective tissue, affecting mostly the skeletal, ocular and cardiovascular systems, caused by mutations in the FBN1 gene. The existence of modifier genes has been postulated based on the wide clinical variability of manifestations in patients, even among those with the same FBN1 mutation. Although isogenic mouse models of the disease were fundamental in dissecting the molecular mechanism of pathogenesis, they do not address the effect of genetic background on the disease phenotype. Here, we use a new mouse model, mgΔloxPneo, which presents different phenotype severity dependent on the genetic backgrounds, to identify genes involved in modulating MFS phenotype. F2 heterozygotes showed wide phenotypic variability, with no correlations between phenotypic severities of the different affected systems, indicating that each has its specific set of modifier genes. Individual analysis of the phenotypes, with SNP microarrays, identified two suggestive QTL each to the cardiovascular and skeletal, and one significant QTL to the skeletal phenotype. Epistatic interactions between the QTL account for 47.4% and 53.5% of variation in the skeletal and cardiovascular phenotypes, respectively. This is the first study that maps modifier loci for MFS, showing the complex genetic architecture underlying the disease.
Sleep and mood disorders in dry eye disease and allied irritating ocular diseases
Authors: Ayaki Masahiko , Kawashima Motoko , Negishi Kazuno , Kishimoto Taishiro , Mimura Masaru , Tsubota Kazuo
Published: March 2016

The aim of the present study was to evaluate sleep and mood disorders in patients with irritating ocular diseases. The study design was a cross-sectional/case-control study conducted in six eye clinics. Out of 715 outpatients diagnosed with irritating ocular surface diseases and initially enrolled, 301 patients with dry eye disease (DED) and 202 age-matched control participants with other ocular surface diseases were analyzed. The mean Pittsburgh Sleep Quality Index (PSQI) and Hospital Anxiety and Depression Scale (HADS) scores were 6.4 ± 3.2 and 11.1 ± 5.7 for severe DED (n = 146), 5.5 ± 3.3 and 9.8 ± 4.0 for mild DED (n = 155), 5.5 ± 3.1 and 9.5 ± 6.6 for chronic conjunctivitis (n = 124), and 5.0 ± 3.3 and 8.9 ± 5.3 for allergic conjunctivitis (n = 78). There were significant differences among these diagnostic groups for PSQI (P < 0.05). Regression analysis of patients with DED revealed the PSQI and HADS scores were significantly correlated with the severity of DED (P < 0.05). Our results demonstrate that sleep quality in patients with DED is significantly worse than in patients with other irritating ocular surface diseases and it is correlated with the severity of DED.
Social cognition and prefrontal hemodynamic responses during a working memory task in schizophrenia
Authors: Pu Shenghong , Nakagome Kazuyuki , Yamada Takeshi , Itakura Masashi , Yamanashi Takehiko , Yamada Sayaka , Masai Mieko , Miura Akihiko , Yamauchi Takahira , Satake Takahiro , Iwata Masaaki , Nagata Izumi , Roberts David L. , Kaneko Koichi
Published: March 2016

Social cognition is an important determinant of functional impairment in schizophrenia, but its relationship with the prefrontal functional abnormalities associated with the condition is still unclear. The present study aimed to explore the relationship between social cognition and prefrontal function in patients with schizophrenia using 52-channel near-infrared spectroscopy (NIRS). Twenty-six patients with schizophrenia and 26 age-, gender-, and intelligence quotient-matched healthy controls (HCs) participated in the study. Hemodynamic responses in the prefrontal and superior temporal cortical regions were assessed during a working memory task using NIRS. Social cognition was assessed using the Social Cognition Screening Questionnaire (SCSQ). The observed hemodynamic responses were significantly reduced in the lateral prefrontal cortex (PFC), the frontopolar cortex, and temporal regions in subjects with schizophrenia compared to HCs. Additionally, lateral PFC hemodynamic responses assessed during the working memory task demonstrated a strong positive correlation with the SCSQ theory of mind (ToM) subscale score even after controlling for working memory performance. These results suggest that ToM integrity is closely related to lateral PFC functional abnormalities found in patients with schizophrenia. In addition, this study provides evidence to suggest that NIRS could be used to identify biomarkers of social cognition function in subjects with schizophrenia.
Thermal Conductivity of Wurtzite Zinc-Oxide from First-Principles Lattice Dynamics – a Comparative Study with Gallium Nitride
Authors: Wu Xufei , Lee Jonghoon , Varshney Vikas , Wohlwend Jennifer L. , Roy Ajit K. , Luo Tengfei
Published: March 2016

Wurtzite Zinc-Oxide (w-ZnO) is a wide bandgap semiconductor that holds promise in power electronics applications, where heat dissipation is of critical importance. However, large discrepancies exist in the literature on the thermal conductivity of w-ZnO. In this paper, we determine the thermal conductivity of w-ZnO using first-principles lattice dynamics and compare it to that of wurtzite Gallium-Nitride (w-GaN) – another important wide bandgap semiconductor with the same crystal structure and similar atomic masses as w-ZnO. However, the thermal conductivity values show large differences (400 W/mK of w-GaN vs. 50 W/mK of w-ZnO at room temperature). It is found that the much lower thermal conductivity of ZnO originates from the smaller phonon group velocities, larger three-phonon scattering phase space and larger anharmonicity. Compared to w-GaN, w-ZnO has a smaller frequency gap in phonon dispersion, which is responsible for the stronger anharmonic phonon scattering and the weaker interatomic bonds in w-ZnO leads to smaller phonon group velocities. The thermal conductivity of w-ZnO also shows strong size effect with nano-sized grains or structures. The results from this work help identify the cause of large discrepancies in w-ZnO thermal conductivity and will provide in-depth understanding of phonon dynamics for the design of w-ZnO-based electronics.
Distinct effects of folate pathway genes MTHFR and MTHFD1L on ruminative response style: a potential risk mechanism for depression
Authors: Eszlari N , Kovacs D , Petschner P , Pap D , Gonda X , Elliott R , Anderson I M , Deakin J F W , Bagdy G , Juhasz G
Published: March 2016

Alterations in the folate pathway have been related to both major depression and cognitive inflexibility; however, they have not been investigated in the genetic background of ruminative response style, which is a form of perseverative cognition and a risk factor for depression. In the present study, we explored the association of rumination (measured by the Ruminative Responses Scale) with polymorphisms of two distinct folate pathway genes, MTHFR rs1801133 (C677T) and MTHFD1L rs11754661, in a combined European white sample from Budapest, Hungary (n=895) and Manchester, United Kingdom (n=1309). Post hoc analysis investigated whether the association could be replicated in each of the two samples, and the relationship between folate pathway genes, rumination, lifetime depression and Brief Symptom Inventory depression score. Despite its functional effect on folate metabolism, the MTHFR rs1801133 showed no effect on rumination. However, the A allele of MTHFD1L rs11754661 was significantly associated with greater rumination, and this effect was replicated in both the Budapest and Manchester samples. In addition, rumination completely mediated the effects of MTHFD1L rs11754661 on depression phenotypes. These findings suggest that the MTHFD1L gene, and thus the C1-THF synthase enzyme of the folate pathway localized in mitochondria, has an important effect on the pathophysiology of depression through rumination, and maybe via this cognitive intermediate phenotype on other mental and physical disorders. Further research should unravel whether the reversible metabolic effect of MTHFD1L is responsible for increased rumination or other long-term effects on brain development.
Hormone glucagon: electrooxidation and determination at carbon nanotubes
Authors: Karra Sushma , Griffith Wendell P. , Kennedy Robert T. , Gorski Waldemar
Published: March 2016

Direct amperometric determination of unlabeled glucagon is a rapid alternative to the complex analytical assays of this peptide hormone.
Immobilization of a non-heme diiron complex encapsulated in an ammonium-type ionic liquid layer modified on an Au electrode: reactivity of the electrode for O2reduction
Authors: Kitagawa Tatsuya , Nishino Junpei , Inomata Tomohiko , Ozawa Tomohiro , Funahashi Yasuhiro , Masuda Hideki
Published: March 2016

A non-heme diiron complex, possessing dioxygen activation ability, has been encapsulated by an ionic liquid self-assembled mono-layer modified on an Au electrode.
Photoactivatable CO release from engineered protein crystals to modulate NF-κB activation
Authors: Tabe Hiroyasu , Shimoi Takuya , Boudes Marion , Abe Satoshi , Coulibaly Fasséli , Kitagawa Susumu , Mori Hajime , Ueno Takafumi
Published: March 2016

Photoactivatable CO releasing materials were developed by immobilization of Mn carbonyl complexes in polyhedral crystals.
On the mechanism of electrochemical ammonia synthesis on the Ru catalyst
Authors: Back Seoin , Jung Yousung
Published: March 2016

The nitrogen reduction reaction (NRR) pathways involving various N–N dissociation steps are found to be comparable to the conventional associative mechanism. The competitive hydrogen adsorption and evolution is revealed to negatively affect the NRR for two reasons, an increase in NRR overpotentials as a function of partial H-coverages as well as a decreased number of active sites.
Generation of spin in single cholesterol molecules on gold
Authors: Karan Sujoy , Berndt Richard
Published: March 2016

A spin is created and annihilated in a single cholesterol molecule on gold by passing current through it.
Hexagonal pillar structure of heteroepitaxial titania–vanadia nanocrystal films for high performance in thermochromic and photocatalytic properties
Authors: Zhou Pei-Yin , Cheng Chih-Chia , Huang Chi-Hsien , Chen Jem-Kun
Published: March 2016

We employed the mixture of Ti and V sols with various ratios to generate hexagonal pillar structure of the composites.
Antitumor and biological investigation of doubly cyclometalated ruthenium(ii) organometallics derived from benzimidazolyl derivatives
Authors: Elumalai Palani , Jeong Yong Joon , Park Dae Won , Kim Dong Hwan , Kim Hyunuk , Kang Se Chan , Chi Ki-Whan
Published: March 2016

In this study, we report the synthesis, anticancer and biological properties of three doubly cyclometalated phenylbenzimidazole derived ruthenium(ii) organometallics (1–3) and their corresponding three organic ligands.
Template-free electrodeposition of AlFe alloy nanowires from a room-temperature ionic liquid as an anode material for Li-ion batteries
Authors: Chen Gang , Chen Yuqi , Guo Qingjun , Wang Heng , Li Bing
Published: March 2016

AlFe alloy nanowires were directly electrodeposited on copper substrates from trimethylamine hydrochloride (TMHC)–AlCl3 ionic liquids with small amounts of FeCl3 at room temperature without templates. Coin cells composed of AlFe alloy nanowire electrodes and lithium foils were assembled to characterize the alloy electrochemical properties by galvanostatic charge/discharge tests. Effects of FeCl3 concentration, potential and temperature on the alloy morphology, composition and cyclic performance were examined. Addition of Fe into the alloy changed the nanowires from a ‘hill-like’ bulk morphology to a free-standing morphology, and increased the coverage area of the alloy on Cu substrates. As an inactive element, Fe could also buffer the alloys' large volume changes during Li intercalation and deintercalation. AlFe alloy nanowires composed of a small amount of Fe with an average diameter of 140 nm exhibited an outstanding cyclic performance and delivered a specific capacity of about 570 mA h g−1 after 50 cycles. This advanced template-free method for the direct preparation of high performance nanostructure AlFe alloy anode materials is quite simple and inexpensive, which presents a promising prospect for practical application in Li-ion batteries.
Towards an integrated understanding of the therapeutic utility of exclusive enteral nutrition in the treatment of Crohn's disease
Authors: Ó Cuív Páraic , Begun Jakob , Keely Simon , Lewindon Peter J. , Morrison Mark
Published: March 2016

The therapeutic effects associated with EEN may be mediated by co-ordinate effects on the host gut mucosa and microbiota.
Rapid separation scheme of Sr, Nd, Pb, and Hf from a single rock digest using a tandem chromatography column prior to isotope ratio measurements by mass spectrometry
Authors: Li Chao-Feng , Wang Xuan-Ce , Guo Jing-Hui , Chu Zhu-Yin , Feng Lian-Jun
Published: March 2016

A straightforward tandem column separation procedure is presented for the separation of Sr, Nd, Pb, and Hf from silicate materials.
In vitro cardiomyocyte-driven biogenerator based on aligned piezoelectric nanofibers
Authors: Liu Xia , Zhao Hui , Lu Yingxian , Li Song , Lin Liwei , Du Yanan , Wang Xiaohong
Published: March 2016

We present a novel contractile cardiomyocyte-driven piezoelectric nanofiber (CCDPN) biogenerator, which conceptually introduces quantitative mechanical-to-electrical energy conversion of neonatal cardiomyocytes.
Hydrogen-treated BiFeO3 nanoparticles with enhanced photoelectrochemical performance
Authors: Zhang Chao , Li Yanhong , Chu Mengsha , Rong Nannan , Xiao Peng , Zhang Yunhuai
Published: March 2016

Compared with pristine BiFeO3, hydrogen-treated BiFeO3 nanoparticles exhibit higher photoelectrochemical performance.
Facile formation of a hierarchical TiO2–SnO2 nanocomposite architecture for efficient dye-sensitized solar cells
Authors: Lim C. K. , Wang Y. , Zhang L.
Published: March 2016

Hierarchical TiO2–SnO2 nano-architecture for efficient DSSC.
Effect of algal species and light intensity on the performance of an air-lift-type microbial carbon capture cell with an algae-assisted cathode
Authors: Hu Xia , Zhou Jiti , Liu Baojun
Published: March 2016

The effect of algal species (Chlorella vulgarisandChlorellasp.) and light intensity on the performance of air-lift-type microbial carbon capture cells (ALMCCs) was investigated.
Observation of large dielectric permittivity and dielectric relaxation phenomenon in Mn-doped lanthanum gallate
Authors: Rai Hari Mohan , Saxena Shailendra K. , Late Ravikiran , Mishra Vikash , Rajput Parasmani , Sagdeo Archna , Kumar Rajesh , Sagdeo P. R.
Published: March 2016

Shifting of tan δ-peaks (100 Hz to 1 MHz) towards higher temperature; featuring dielectric relaxation.
Bioinspired polydopamine-layered double hydroxide nanocomposites: controlled synthesis and multifunctional performance
Authors: Nam Hye Jin , Park Eun Bi , Jung Duk-Young
Published: March 2016

Interlayer polymerization of dopamine into a LDH layer enabled the preparation of multifunctional hybrid nanostructures with strong adhesion and high specific capacitance.
Biomaterials for pluripotent stem cell engineering: from fate determination to vascularization
Authors: Seale Nailah M. , Varghese Shyni
Published: March 2016

Recent advancements in materials science and engineering may hold the key to overcoming reproducibility and scalability limitations currently hindering the clinical translation of stem cell therapies.
Alkylsulfuric acid ionic liquids: a promising class of strongly acidic room-temperature ionic liquids
Authors: Dupont David , Renders Evelien , Binnemans Koen
Published: March 2016

Alkylsulfuric acid ILs are simple to make and offer a more strongly acidic alternative to sulfonic acid ILs for applications in catalysis, metal extraction and dissolution of metal oxides.
Polydopamine-coated open cell polyurethane foams as an inexpensive, flexible yet robust catalyst support: a proof of concept
Authors: Pardieu Elodie , Chau Nguyet Trang Thanh , Dintzer Thierry , Romero Thierry , Favier Damien , Roland Thierry , Edouard David , Jierry Loïc , Ritleng Vincent
Published: March 2016

A novel type of robust yet flexible structured catalytic support, easily accessible via an inexpensive and green process, is described.
A photosensitizing decatungstate-based MOF as heterogeneous photocatalyst for the selective C–H alkylation of aliphatic nitriles
Authors: Shi Dongying , He Cheng , Sun Wenlong , Ming Zheng , Meng Changgong , Duan Chunying
Published: March 2016

A photosensitizing decatungstate-based MOF with 1D channels was achieved for light-driven the β- or γ-site C–H alkylation of aliphatic nitriles, which offered an environmental-friendly route in both the laboratory and industry.
Highly crystalline covalent organic frameworks from flexible building blocks
Authors: Xu Liqian , Ding San-Yuan , Liu Junmin , Sun Junliang , Wang Wei , Zheng Qi-Yu
Published: March 2016

Highly crystalline covalent organic frameworks were synthesized from flexible 2,4,6-triaryloxy-1,3,5-triazine building blocks on a gram scale, and the cooperative weak interactions play a key role in the formation of porous frameworks.
Defects in the calcium-binding region drastically affect the cadherin-like domains of RET tyrosine kinase
Authors: Gao Chunxia , Grøtli Morten , Eriksson Leif A.
Published: March 2016

Changes in the calcium binding region of the cadherin-like domain of RET tyrosine kinase alters protein structure and function.
Thermal optical non-linearity of nematic mesophase enhanced by gold nanoparticles – an experimental and numerical investigation
Authors: Kurochkin O. , Murugesan Y. K. , Bennett T. P. , D'Alessandro G. , Reznikov Y. , Tang B. J. , Mehl G. H. , Kaczmarek M.
Published: March 2016

In this work the mechanisms leading to the enhancement of optical nonlinearity of nematic liquid crystalline materials through localized heating by doping the liquid crystals (LCs) with gold nanoparticles (GNPs) are investigated.
Probing the reactivity of pentaphenylborole with N–H, O–H, P–H, and S–H bonds
Authors: Yruegas Sam , Huang Kexuan , Wilson David J. D. , Dutton Jason L. , Martin Caleb D.
Published: March 2016

The reactions of molecules containing E–H functionalities (E = Group 15 or 16 element) and pentaphenylborole were investigated revealing diverse outcomes.
Unique trapping of paddlewheel copper(ii) carboxylate by ligand-bound {Cu2} fragments for [Cu6] assembly
Authors: Chattopadhyay Krishna , Shaw Bikash Kumar , Saha Shyamal Kumar , Ray Debashis
Published: March 2016

Trapping of paddlewheel {Cu2(carboxylate)4} by ligand-bound {Cu2(μ-H2L)}3+ units resulted in dumbbell-shaped [Cu6] complexes modulating the tetracarboxylate bridged Cu⋯Cu separations.
Isopentatungstate-supported metal carbonyl derivative: synthesis, characterization, and catalytic properties for alkene epoxidation
Authors: Li Jie , Guo Jipeng , Jia Jiage , Ma Pengtao , Zhang Dongdi , Wang Jingping , Niu Jingyang
Published: March 2016

An isopentatungstate-supported metal carbonyl derivative has been synthesized and characterized, and can efficiently catalyze alkene epoxidation with high activity.
Multinuclear silver(i) XPhos complexes with cyclooctatetraene: photochemical C–C bond cleavage of acetonitrile and cyanide bridged Ag cluster formation
Authors: Grirrane A. , Álvarez E. , Albero J. , García H. , Corma A.
Published: March 2016

Fluxional cationic multi-silver(i) complexes [(XPhos-Ag)n(COT)][SbF6]n and Ag clusters [(XPhos-Ag)2(μ-CN)n(μ-Ag)n−1] (n = 1, 2, 3, 4) have been isolated and fully characterized.
Allylic borylation of tertiary allylic alcohols: a divergent and straightforward access to allylic boronates
Authors: Harada Kohei , Nogami Marina , Hirano Keiichi , Kurauchi Daisuke , Kato Hisano , Miyamoto Kazunori , Saito Tatsuo , Uchiyama Masanobu
Published: March 2016

A novel method for the preparation of diverse allylic boronates from simple allylic alcohols is reported.
Superhydrophilicity and spontaneous spreading on zwitterionic surfaces: carboxybetaine and sulfobetaine
Authors: Wu Cyuan-Jhang , Huang Chun-Jen , Jiang Shaoyi , Sheng Yu-Jane , Tsao Heng-Kwong
Published: March 2016

Wetting behavior of zwitterionic surfaces fabricated by grafting sulfobetaine silane (SBSi) and carboxybetaine silane (CBSi) on glass slides.
Evaluation of the antimicrobial activity of Moringa oleifera seed extract as a sustainable solution for potable water
Authors: Dasgupta Saumyadeb , Kumar Gunda Naga Siva , Mitra Sushanta K.
Published: March 2016

We have provided a detailed antimicrobial study of the seed extract ofMoringa oleifera, a common medicinal plant.
Slow-binding inhibition of acetylcholinesterase by an alkylammonium derivative of 6-methyluracil: mechanism and possible advantages for myasthenia gravis treatment
Authors: Kharlamova Alexandra D. , Lushchekina Sofya V. , Petrov Konstantin A. , Kots Ekaterina D. , Nachon Florian , Villard-Wandhammer Marielle , Zueva Irina V. , Krejci Eric , Reznik Vladimir S. , Zobov Vladimir V. , Nikolsky Evgeny E. , Masson Patrick
Published: March 2016

Inhibition of human AChE (acetylcholinesterase) and BChE (butyrylcholinesterase) by an alkylammonium derivative of 6-methyluracil, C-547, a potential drug for the treatment of MG (myasthenia gravis) was studied. Kinetic analysis of AChE inhibition showed that C-547 is a slow-binding inhibitor of type B, i.e. after formation of the initial enzyme·inhibitor complex (Ki=140 pM), an induced-fit step allows establishment of the final complex (Ki*=22 pM). The estimated koff is low, 0.05 min−1. On the other hand, reversible inhibition of human BChE is a fast-binding process of mixed-type (Ki=1.77 μM; Ki′=3.17 μM). The crystal structure of mouse AChE complexed with C-547 was solved at 3.13 Å resolution. The complex is stabilized by cation–π, stacking and hydrogen-bonding interactions. Molecular dynamics simulations of the binding/dissociation processes of C-547 and C-35 (a non-charged analogue) to mouse and human AChEs were performed. Molecular modelling on mouse and human AChE showed that the slow step results from an enzyme conformational change that allows C-547 to cross the bottleneck in the active-site gorge, followed by formation of tight complex, as observed in the crystal structure. In contrast, the related non-charged compound C-35 is not a slow-binding inhibitor. It does not cross the bottleneck because it is not sensitive to the electrostatic driving force to reach the bottom of the gorge. Thus C-547 is one of the most potent and selective reversible inhibitors of AChE with a long residence time, τ=20 min, longer than for other reversible inhibitors used in the treatment of MG. This makes C-547 a promising drug for the treatment of this disease.
Miniaturised active integrated antennas: a co‐design approach
Authors: Sharawi Mohammad S. , Dhar Sagar K. , Hammi Oualid , Ghannouchi Fadhel M.
Published: March 2016

A co‐design methodology for antenna miniaturisation with an integrated radio frequency (RF) amplifier is proposed for power‐efficient and compact RF front‐ends. This approach relaxes the standalone antenna matching requirement which is of interest in miniaturised antenna design. The detailed design and measurement procedure is presented and the concept is demonstrated with two examples for both narrowband and wideband scenarios considering transmitting and receiving front‐ends. The amplifiers and the antennas are co‐designed so that optimum performance is achieved in terms of gain, noise figure and efficiency. The antenna has the size of 0.033λ02 at 2.45 GHz. It is miniaturised from its natural resonance frequency of 3.5–2.45 GHz which provides 51% of size reduction. The minimum bandwidth of the integrated antenna is found to be 37 and 150 MHz, respectively, for the narrowband and wideband designs. The active integrated antenna (AIA) efficiency is more than 47% when operating in the band of 2.45–2.6 GHz. The gain and noise figure of the AIA systems are optimised along with the antenna performance and found to be >10 dB and <2 dB, respectively. Measurement results are presented which are in well agreement with the design procedure and simulations.
Research on DC voltage balancing control method of star connection cascaded H‐bridge static var generator
Authors: He Yingjie , Duan Wenyan , Fu Yabin
Published: March 2016

In‐depth study of the DC side voltage control of the star connection cascaded H‐bridge multilevel static var generator has been made in this study. Moreover, a three‐layer DC side voltage control system has been established. The first layer is overall DC side voltage control. The overall DC side voltage of three phases A, B and C is maintained constant through generating fundamental positive sequence active current. The second layer is balancing control between three phases. Through injecting zero sequence voltage into the voltage command, the authors can redistribute three‐phase active power, in order to maintain three‐phase DC side voltages balanced; in this method, fast dynamic control can be achieved through feeding forward the power that grid voltage and converter current produce. The third layer is balancing control between modules of each phase. Through adjusting voltage commands of H‐bridge modules of each phase along the direction of the converter current, they can redistribute the active power absorbed by each module, in order to ensure that DC side voltages of modules of each phase are equal to each other. Experimental results verify the correctness and reliability of the proposed control system in the end.
On-chip three-dimensional tissue histology for microbiopsies
Authors: Narciso Cody , Cowdrick Kyle R. , Zellmer Victoria , Brito-Robinson Teresa , Brodskiy Pavel , Hoelzle David J. , Zhang Siyuan , Zartman Jeremiah J.
Published: March 2016

We report a novel approach that generates a high resolution, three-dimensional (3D) fluorescent staining atlas of tissue microbiopsies in a microfluidic device without destroying the tissue. We demonstrate that this method preserves tissue architecture for multiple murine organs by comparing traditional 2D slices to an optically sectioned 3D H&E-mimic. The H&E-mimic slices show a close qualitative match to traditional H&E. The 3D spatial and molecular information obtainable from this method significantly increases the amount of data available for evaluating both tissue morphology and specific biomarkers in a wide range of both research and clinically driven applications and is amenable to automation.
Relating spatially resolved maps of the Schottky barrier height to metal/semiconductor interface composition
Authors: Balsano Robert , Durcan Chris , Matsubayashi Akitomo , Narasimham Avyaya J. , LaBella Vincent P.
Published: March 2016

The Schottky barrier height (SBH) is mapped with nanoscale resolution at pure Au/Si(001) and mixed Au/Ag/Si(001) interfaces utilizing ballistic electron emission microscopy by acquiring and fitting spectra every 11.7 nm × 11.7 nm over a 1 μm × 1 μm area. The SBH distributions for the mixed interfaces are about four times broader than the pure gold interface and have a complex structure arising from the incomplete intermixing and its effects on the scattering of hot electrons. The maps of the barrier heights and amplitudes for the mixed samples are inhomogeneous with localization attributed to the disordered mixture of the Au and Ag. A method to calculate ratio of the Au to Ag Schottky barrier heights is presented and discussed in relationship to the interface composition. These results demonstrate how the Schottky barrier height is a function of position at the interface, and how mapping can capture the electrostatic nature of these and possibly other mixed metal–semiconductor interfaces.
Defect chemistry and electronic transport in low-κ dielectrics studied with electrically detected magnetic resonance
Authors: Mutch Michael J. , Lenahan Patrick M. , King Sean W.
Published: March 2016

Defect mediated electronic transport phenomena in low-κ dielectric films are of great technological interest for state-of-the-art and next generation microprocessors. At the present time, the leading low-κ interlayer dielectrics and etch-stop layers are based upon a-SiOC:H and a-SiCN:H, respectively. In this study, we utilize electrically detected magnetic resonance (EDMR), a derivative of electron paramagnetic resonance, to provide physical insight into electronic transport, as well as the nature and origin of defects in dense and porous a-SiOC:H and dense a-SiCN:H films. Resonance measurements are performed before and after the removal of sacrificial porogens via UV treatments to understand the role of specific defect centers in electronic transport in a-SiOC:H systems, and the nature of defects created by UV treatments. Unfortunately, a-SiOC:H and a-SiCN:H EDMR spectra are relatively broad and featureless. These featureless spectra are consistent with fairly complex a-SiOC:H and a-SiCN:H systems. We argue that physical insight may be gleaned from featureless spectra via multiple frequency EDMR. Baseline multiple frequency EDMR measurements are performed in a-Si:H and a-C:H to illustrate the nature of line broadening mechanisms of silicon and carbon related defects.
Evaluation of the lifting line vortex model approximation for estimating the local blade flow fields in horizontal-axis wind turbines
Authors: Sant T. , del Campo V. , Micallef D. , Ferreira C. S.
Published: March 2016

Lifting line vortex models have been widely used to predict flow fields around wind turbine rotors. Such models are known to be deficient in modelling flow fields close to the blades due to the assumption that blade vorticity is concentrated on a line and consequently the influences of blade geometry are not well captured. The present study thoroughly assessed the errors arising from this approximation by prescribing the bound circulation as a boundary condition on the flow using a lifting line free-wake vortex approach. The bound circulation prescribed to free-wake vortex model was calculated from two independent sources using (1) experimental results from SPIV and (2) data generated from a 3D panel free-wake vortex approach, where the blade geometry is fully modelled. The axial and tangential flow fields around the blades from the lifting line vortex model were then compared with those directly produced by SPIV and the 3D panel model. The comparison was carried out for different radial locations across the blade span. The study revealed the cumulative probability error distributions in lifting line model estimations for the local aerofoil flow field under both 3D rotating and 2D non-rotating conditions. It was found that the errors in a 3D rotating environment are considerably larger than those for a wing of infinite span in 2D flow. Finally, a method based on the Cassini ovals theory is presented for defining regions around rotating blades for which the lifting line model is unreliable for estimating the flow fields.
Optimizing the magnitude of the magnetoresistance observed in ferromagnet/superconductor/ferromagnet trilayers: A formula to combine all involved parameters
Authors: Aristomenopoulou E. , Zeibekis M. , Stamopoulos D.
Published: March 2016

The competitive nature of ferromagnetism and superconductivity in Ferromagnet/Superconductor (FM/SC) hybrids has attracted much interest in the last decades. In particular, the superconducting magnetoresistance (SMR) observed in FM/SC/FM trilayers (TLs) is related to the manipulation of the transport properties of the SC interlayer by the magnetic domain structure of the FM outer layers with out-of-plane anisotropy. In our recent work [Sci. Rep. 5, 13420 (2015)], a phenomenological model was proposed that describes successfully the scaling of the SMR magnitude with the relevant macroscopic parameters and microscopic length scales of the SC and FM structural units. Based on this model, here we investigate the contribution of the parameters that affect indirectly the SMR magnitude and do not appear in the original model. To this end, the parameters of both the SC interlayer (i.e., the thickness, dSC, the mean free path, l, the coherence length, ξ(0), etc.) and the FM outer layers (i.e., the thickness, dFM) are examined. The theoretical simulations presented here and experimental data unveil the indirect contribution of these parameters on the magnitude of the SMR and confirm the predictive power of the original phenomenological model. Accordingly, this model can be employed as a generic formula to combine successfully all involved parameters in every kind of FM/SC/FM TLs, ultimately optimizing the magnitude of the SMR.
Effects of inter-subband couplings on bound and extended states of terahertz cascade structures
Authors: Ndebeka-Bandou C. , Carosella F. , Bastard G.
Published: March 2016

We theoretically analyze the effect of inter-subband couplings on the eigenstates of a terahertz heterostructure in the presence of coulombic donors. We find that the inter-subband electron-donor interaction causes a drastic reorganization of the eigenenergies and a strong admixture between the subbands that decisively influences the optical absorption spectrum of the structure. These results illustrate the importance of the inter-subband couplings in the formulation of the eigenstates of imperfect terahertz heterostructures.
Recombination kinetics of photogenerated electrons in InGaAs/InP quantum wells
Authors: Tito M. A. , Pusep Yu. A. , Gold A. , Teodoro M. D. , Marques G. E. , LaPierre R. R.
Published: March 2016

The electron transport and recombination processes of photoexcited electron-hole pairs were studied in InGaAs/InP single quantum wells. Comprehensive transport data analysis reveals a asymmetric shape of the quantum well potential where the electron mobility was found to be dominated by interface-roughness scattering. The low-temperature time-resolved photoluminescence was employed to investigate recombination kinetics of photogenerated electrons. Remarkable modification of Auger recombination was observed with variation of the electron mobility. In high mobility quantum wells, the increasing pump power resulted in a new and unexpected phenomenon: a considerably enhanced Auger non-radiative recombination time. We propose that the distribution of the photoexcited electrons over different conduction band valleys might account for this effect. In low mobility quantum wells, disorder-induced relaxation of the momentum conservation rule causes inter-valley transitions to be insignificant; as a consequence, the non-radiative recombination time is reduced with the increase in pump power. Thus, interface-roughness scattering was found responsible for both transport properties and dynamic optical response in InGaAs/InP quantum wells.
Influence of oval defects on transport properties in high-mobility two-dimensional electron gases
Authors: Bockhorn L. , Velieva A. , Hakim S. , Wagner T. , Rugeramigabo E. P. , Schuh D. , Reichl C. , Wegscheider W. , Haug R. J.
Published: March 2016

Rare macroscopic growth defects next to a two-dimensional electron gas influence transport properties and cause a negative magnetoresistance. On the basis of this, we show that the number of oval defects seen on the material surface is comparable with the density of macroscopic growth defects determined from the negative magnetoresistance. We examine several materials with different densities of oval defects nS which were grown in one cycle under the same conditions to verify our observations. Paradoxically, the material with the largest number of oval defects has also the highest electron mobility.
Analytical and experimental investigation of electrical characteristics of a metallic insulation GdBCO coil
Authors: Yang D. G. , Choi Y. H. , Kim Y. G. , Song J. B. , Lee H. G.
Published: March 2016

This paper presents results, experimental and analytical, of the electrical characteristics of GdBCO single-pancake coils co-wound with a brass tape as metallic insulation (MI coil). The GdBCO pancakes were subjected to sudden discharge, charge-discharge, and over-current tests. The sudden discharge and charge-discharge test results of the MI coil demonstrated that MI coils can be charged and discharged significantly faster than non-insulated coils that are wound only with GdBCO tape. In over-current tests at 150 A (1.25Ic), the MI coil exhibited better electrical behavior, i.e., self-protecting features, than its counterpart co-wound with Kapton tape, an insulator. Moreover, the experimental and analytical results are in agreement, validating the use of a concise equivalent parallel-RL circuit model for the MI coil to characterize its electrical behavior. Overall, the MI winding technique is highly promising to help build compact, mechanically robust, and self-protecting magnets composed of REBCO pancake coils. With no organic material in the winding, MI REBCO pancakes will be immune to neutron radiation damage, making the MI winding technique a viable option for fusion reactors, such as for toroidal field, poroidal field magnets, and central solenoid.
Atomically flat reconstructed rutile TiO2(001) surfaces for oxide film growth
Authors: Wang Y. , Lee S. , Vilmercati P. , Lee H. N. , Weitering H. H. , Snijders P. C.
Published: March 2016

The availability of low-index rutile TiO2 single crystal substrates with atomically flat surfaces is essential for enabling epitaxial growth of rutile transition metal oxide films. The high surface energy of the rutile (001) surface often leads to surface faceting, which precludes the sputter and annealing treatment commonly used for the preparation of clean and atomically flat TiO2(110) substrate surfaces. In this work, we reveal that stable and atomically flat rutile TiO2(001) surfaces can be prepared with an atomically ordered reconstructed surface already during a furnace annealing treatment in air. We tentatively ascribe this result to the decrease in surface energy associated with the surface reconstruction, which removes the driving force for faceting. Despite the narrow temperature window where this morphology can initially be formed, we demonstrate that it persists in homoepitaxial growth of TiO2(001) thin films. The stabilization of surface reconstructions that prevent faceting of high-surface-energy crystal faces may offer a promising avenue towards the realization of a wider range of high quality epitaxial transition metal oxide heterostructures.
Observation of magnetoelectric effects in a S=12 frustrated spin chain magnet SrCuTe2O6
Authors: Koteswararao B. , Yoo Kyongjun , Chou F. C. , Kim Kee Hoon
Published: March 2016

The magnetoelectric effects are investigated in a cubic compound SrCuTe2O6, in which uniform Cu2+ (S = 1/2) spin chains with considerable spin frustration exhibit a concomitant antiferromagnetic transition and dielectric constant peak at TN ≈ 5.5 K. Pyroelectric Jp(T) and magnetoelectric current JME(H) measurements in the presence of a bias electric field are used to reveal that SrCuTe2O6 shows clear variations of Jp(T) across TN at constant magnetic fields. Furthermore, isothermal measurements of JME(H) also develop clear peaks at finite magnetic fields, of which traces are consistent with the spin-flop transitions observed in the magnetization studies. As a result, the anomalies observed in Jp(T) and JME(H) curves match well with the field-temperature phase diagram constructed from magnetization and dielectric constant measurements, demonstrating that SrCuTe2O6 is a new magnetoelectric compound with S = 1/2 spin chains.
High Ms Fe16N2 thin film with Ag under layer on GaAs substrate
Authors: Zhang Xiaowei , Jiang Yanfeng , Yang Meiyin , Allard Lawrence F. , Wang Jian-Ping
Published: March 2016

(001) textured Fe16N2 thin film with Ag under layer is successfully grown on GaAs substrate using a facing target sputtering (FTS) system. After post annealing, chemically ordered Fe16N2 phase is formed and detected by X-ray diffraction (XRD). High saturation magnetization (Ms) is measured by a vibrating sample magnetometer (VSM). In comparison with Fe16N2 with Ag under layer on MgO substrate and Fe16N2 with Fe under layer on GaAs substrate, the current layer structure shows a higher Ms value, with a magnetically softer feature in contrast to the above cases. In addition, X-ray photoelectron spectroscopy (XPS) is performed to characterize the binding energy of N atoms. To verify the role of strain that the FeN layer experiences in the above three structures, Grazing Incidence X-ray Diffraction (GIXRD) is conducted to reveal a large in-plane lattice constant due to the in-plane biaxial tensile strain.
Synthesis and microwave absorbing characteristics of functionally graded carbonyl iron/polyurethane composites
Authors: Yang R. B. , Liang W. F. , Wu C. H. , Chen C. C.
Published: March 2016

Radar absorbing materials (RAMs) also known as microwave absorbers, which can absorb and dissipate incident electromagnetic wave, are widely used in the fields of radar-cross section reduction, electromagnetic interference (EMI) reduction and human health protection. In this study, the synthesis of functionally graded material (FGM) (CI/Polyurethane composites), which is fabricated with semi-sequentially varied composition along the thickness, is implemented with a genetic algorithm (GA) to optimize the microwave absorption efficiency and bandwidth of FGM. For impedance matching and broad-band design, the original 8-layered FGM was obtained by the GA method to calculate the thickness of each layer for a sequential stacking of FGM from 20, 30, 40, 50, 60, 65, 70 and 75 wt% of CI fillers. The reflection loss of the original 8-layered FGM below –10 dB can be obtained in the frequency range of 5.12∼18 GHz with a total thickness of 9.66 mm. Further optimization reduces the number of the layers and the stacking sequence of the optimized 4-layered FGM is 20, 30, 65, 75 wt% with thickness of 0.8, 1.6, 0.6 and 1.0 mm, respectively. The synthesis and measurement of the optimized 4-layered FGM with a thickness of 4 mm reveal a minimum reflection loss of –25.2 dB at 6.64 GHz and its bandwidth below – 10 dB is larger than 12.8 GHz.
Fabrication and physical properties of [Fe/Fe4N]N multilayers with high saturation magnetization
Authors: Yu B. , Lin L. , Ma B. , Zhang Z. Z. , Jin Q. Y. , Wang J. P.
Published: March 2016

[Fe/Fe4N]N multilayers with high saturation magnetization were prepared on MgO(200) substrate, by the DC reactive magnetron sputtering and then annealed at higher temperature. Their structural and magnetic properties were investigated. Epitaxial growth of α-Fe and γ’-Fe4N were demonstrated on MgO, and then excellent [Fe/Fe4N]N was obtained. Though the saturation magnetizations of the as-deposited [Fe/Fe4N]N are slightly below the average value of those of α-Fe and γ’-Fe4N, the saturation magnetization of the annealed [Fe(3.04 nm)/Fe4N(3.04 nm)]5 increases up to 1850 emu/cc, 32 % larger than that of α-Fe film. N atom diffusion from the γ’-Fe4N to the α-Fe layer at high temperature greatly improves the saturation magnetization.
Room temperature giant magnetoimpedance in polycrystalline La0.75Ba0.25MnO3
Authors: Kumar Pawan , Rubi Km , Mahendiran R.
Published: March 2016

We report the magnetic field dependence of electrical impedance Z in polycrystalline La0.75Ba0.25MnO3 a function of frequency from f = 1 MHz to 1 GHz at room temperature. The magnetoimpedance [MI = ΔZ/Z(0) where ΔZ = Z(H)-Z(0)] is −37.5 % (-58.5%) at 1(10) MHz for H = 1.2 kOe, which far exceeds mere -1.15% dc magnetoresistance. As f increases above 10 MHz, MI decreases in magnitude and changes sign from negative to positive. The change in sign of MI results from the transition of a single peak at H = 0 to two peaks at H = ± Hp accompanied by a minimum at the origin. Hp shifts towards higher field with increasing frequency. The occurrence of giant radio-frequency magnetoimpedance is promising for low-field sensor applications.
Electronic structures of nanocrystalline Fe90-xCuxSi10-yBy soft magnets
Authors: Park Jihoon , Hong Yang-Ki , Lee Woncheol , Bae Seok , Kim Seong-Gon , Choi Chul-Jin
Published: March 2016

We have calculated electronic structures of nanocrystalline Fe90−xCuxSi10−yBy using first principles calculations based on density functional theory (DFT) to obtain saturation magnetic flux density (Bs). The Bs of crystalline (Fe3Si) and amorphous (Fe-B) phases in Fe90−xCuxSi10−yBy were separately calculated, and the total Bs of Fe90−xCuxSi10−yBy was derived by the summation of the Bs for the Fe3Si and Fe-B phases. The calculated Bs of Fe3Si is 1.35 T, and that of Fe-B varies from 2.08 to 2.22 T based on Fe to B ratios. Therefore, a total Bs higher than 1.80 T can be obtained with y ≥ 4 for both x = 1 and 2 in Fe90−xCuxSi10−yBy.
Is the melting Arctic changing midlatitude weather?
Authors: Overland James E.
Published: March 2016

According to model simulations, a warming Arctic can shift the circulation patterns of the polar jet stream and bring frigid air southward. But has it?
The vocal microphone: Technology and practice
Authors: Case Alexander
Published: March 2016

Evolving technologies for converting acoustic pressure into an electrical signal have driven changes in the performance practice and sound of pop singers.
Blackleg disease of canola in Australia
Authors: Van De Wouw A. P. , Marcroft S. J. , Howlett B. J.
Published: March 2016

Blackleg disease caused by the fungus Leptosphaeria maculans is the most important disease of canola worldwide. The impact of this disease on the development of the Australian canola industry, particularly over the last 20 years, is discussed. Deployment of a range of disease control measures has resulted in a thriving canola industry with production now approaching 4 million tonnes annually. Discoveries about disease mechanisms and key plant and fungal genes are described. Analysis of the L. maculans genome sequence has enabled an understanding of how fungal populations can evolve rapidly to overcome disease resistance bred into canola cultivars.