bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical Sensing of Stress in Polymers
Authors: Göstl R. , Clough J. M. , Sijbesma R. P.
Published: October 2017

This chapter discusses recent approaches towards the optical detection of stress and deformation in polymeric materials, an important tool in monitoring material integrity and in the study of failure mechanisms of polymeric materials. Optical sensing has specific advantages based on the ease of detection, high sensitivity and spectral resolution of light. In this chapter, a classification of sensing mechanisms is used that distinguishes between the molecular phenomena of isomerization, bond scission, change in conjugation and collective phenomena such as changes in chromophore aggregation and photonic band gap tuning. Molecular mechanisms are discussed that have been used to obtain stress-induced changes in absorption and fluorescence properties and recent work is presented in which the chain scission of dioxetanes is used to produce a luminescent signal with high detectability. Pi-conjugated systems play an important role in optical detection of stress and damage in polymers because their optical properties are very sensitive to changes in conformation and aggregation state. Finally, photonic band gap polymers and cholesteric liquid crystals are discussed, in which the periodic organization of structural features at the scale of the wavelength of light leads to strain-dependent reflection and absorption bands.
ProxyPhos sensors for the detection of negatively charged membranes
Authors: Murcar-Evans Bronte I. , Cabral Aaron D. , Toutah Krimo , de Araujo Elvin D. , Lai Angel , Macdonald Peter M. , Berger-Becvar Angelika , Kraskouskaya Dziyana , Gunning Patrick T.
Published: October 2017

ProxyPhos sensors selectively detect negatively charged phospholipid membranes.
The first synthesis of meso-dicycloalkylporphycenes: ring strain effects on structural and optical properties of isomeric porphyrins
Authors: Ono Toshikazu , Koga Daiki , Yoza Kenji , Hisaeda Yoshio
Published: October 2017

Two novel meso-dicycloalkylporphycenes were synthesized for the first time, which showed remarkable ring-strain-induced switching of their fluorescence behaviors in the solution phase.
A halogen-bonding-catalyzed Michael addition reaction
Authors: Gliese Jan-Philipp , Jungbauer Stefan H. , Huber Stefan M.
Published: October 2017

The first application of synthetic halogen bond donors as catalysts in a Michael addition reaction is described.
Fluorogenic diazaborine formation of semicarbazide with designed coumarin derivatives
Authors: Cambray Samantha , Bandyopadhyay Anupam , Gao Jianmin
Published: October 2017

Fluorogenic diazaborine conjugation enables facile labeling of bacterial pathogens.
Significant improvement of multi-seed method of diamond synthesis by adjusting the lateral cooling water temperature
Authors: Li Yadong , Wang Chunxiao , Chen Ning , Chen Liangchao , Guo Longsuo , Jia Xiaopeng , Ma Hong-an
Published: October 2017

In this work, we use a multi-seed arrangement assembly with an annular carbon source to synthesize large single-crystals of diamond and investigate the influence of the external environment on the synthesis of diamonds.
Observation of hidden atomic order at the interface between Fe and topological insulator Bi2Te3
Authors: Sánchez-Barriga Jaime , Ogorodnikov Ilya I. , Kuznetsov Mikhail V. , Volykhov Andrey A. , Matsui Fumihiko , Callaert Carolien , Hadermann Joke , Verbitskiy Nikolay I. , Koch Roland J. , Varykhalov Andrei , Rader Oliver , Yashina Lada V.
Published: October 2017

The first compelling evidence of unique atomic order at the ferromagnet Fe/topological insulator Bi2Te3 interface.
Multiconfiguration pair-density functional theory for doublet excitation energies and excited state geometries: the excited states of CN
Authors: Bao Jie J. , Gagliardi Laura , Truhlar Donald G.
Published: October 2017

MC-PDFT is more accurate than CR-EOM-CCSD(T) or TDDFT when averaged over the first four adiabatic excitation energies of CN.
Mechanism and reactivity in the Morita–Baylis–Hillman reaction: the challenge of accurate computations
Authors: Liu Zhen , Patel Chandan , Harvey Jeremy N. , Sunoj Raghavan B.
Published: October 2017

A systematic density functional theory exploration of various reactive steps together with benchmark coupled cluster results are used to propose an accurate model of the mechanism of the Morita–Baylis–Hillman (MBH) reaction in organic chemistry.
Ab initiothermodynamic properties and their uncertainties for crystalline α-methanol
Authors: Červinka Ctirad , Beran Gregory J. O.
Published: October 2017

To investigate the performance of quasi-harmonic electronic structure methods for modeling molecular crystals at finite temperatures and pressures, thermodynamic properties are calculated for the low-temperature α polymorph of crystalline methanol and their computational uncertainties are analyzed.
Unravelling the mechanisms of CO2 hydrogenation to methanol on Cu-based catalysts using first-principles multiscale modelling and experiments
Authors: Huš Matej , Kopač Drejc , Štefančič Neja Strah , Jurković Damjan Lašič , Dasireddy Venkata D. B. C. , Likozar Blaž
Published: October 2017

Multi-scale modelling of various copper-based catalysts showed how and why different catalysts perform in methanol synthesis via carbon dioxide hydrogenation.
Facile generation of iridium PCcarbeneP pincer complexes via water elimination from an alcohol proligand
Authors: Sung Simon , Young Rowan D.
Published: October 2017

We report the facile generation of Ir PCcarbeneP pincer systems.
Estimating the probability of illness due to swimming in recreational water with a mixture of human- and gull-associated microbial source tracking markers
Authors: Brown Kendra I. , Graham Katherine E. , Soller Jeffrey A. , Boehm Alexandria B.
Published: October 2017

The risk of swimming in water contaminated with gull feces and human wastewater was determined using quantitative microbial risk assessment.
Construction of the tetrahydroquinoline spiro skeleton via cascade [1,5]-hydride transfer-involved C(sp3)–H functionalization “on water”
Authors: Zhu Shuai , Chen Chunqi , Xiao Mingyan , Yu Liping , Wang Liang , Xiao Jian
Published: October 2017

Water enabled a highly atom- and step-economical, redox-neutral 4-step cascade process, including SNAr/Knoevenagel condensation/[1,5]-hydride transfer cyclization, to construct pharmaceutically important tetrahydroquinoline spiro compounds efficiently.
Synthesis of ethanol via a reaction of dimethyl ether with CO2 and H2
Authors: Qian Qingli , Cui Meng , Zhang Jingjing , Xiang Junfeng , Song Jinliang , Yang Guanying , Han Buxing
Published: October 2017

Ethanol is very efficiently produced from dimethyl ether, CO2 and H2 by homogeneous catalysis under mild conditions.
Improving the photocatalytic activity of polyaniline and a porphyrin via oxidation to obtain a salt and a charge-transfer complex
Authors: Gottam Ramesh , Srinivasan Palaniappan , La Duong Duc , Bhosale Sheshanath V.
Published: October 2017

Simple, efficient, and one-step polymerization of aniline to a novel polyaniline salt consisting of sulfate and porphyrin dopants as an efficient photocatalyst for dyes.
Oxidation route dependent proton conductivities of oxidized fullerenes
Authors: Rabin Nurun Nahar , Karim Mohammad Razaul , Islam Md. Saidul , Omagari Hitomi , Kameda Narumi , Shudo Yuta , Ohtani Ryo , Nakamura Masaaki , Hayami Shinya
Published: October 2017

Proton conductivities of oxidized fullerenes from different types of oxidizing agents were measured. Among all, NaOH treated fullerenes were showed higher proton conductivity.
Transition-metal-free, visible-light-mediated cyclization of o-azidoarylalkynes with aryl diazonium salts
Authors: Jin Cheng , Su Lianzheng , Ma Daxi , Cheng Mingrong
Published: October 2017

A visible-light promoted transformation of o-azidoarylalkynes and aryl diazonium salts for the synthesis of unsymmetrical 2,3-diaryl-substituted indoles under transition-metal-free conditions was described.
Efficient ring-opening polymerization (ROP) of ε-caprolactone catalysed by isomeric pyridyl β-diketonate iron(iii) complexes
Authors: Lee Sze-Ling , Hu Fei-Long , Shang Xiu-Juan , Shi Yi-Xiang , Tan Ai Ling , Mizera Jens , Clegg Jack K. , Zhang Wen-Hua , Young David J. , Lang Jian-Ping
Published: October 2017

A series of FeL3 complexes of dipyridyl β-diketones were structurally characterized and their catalytic properties investigated.
Phonon coupling and transport in individual polyethylene chains: a comparison study with the bulk crystal
Authors: Wang Xinjiang , Kaviany Massoud , Huang Baoling
Published: October 2017

Using the first-principles-based anharmonic lattice dynamics, we calculate the thermal conductivities (κ) of both bulk and single-chain polyethylene (PE) and characterize the mode-wise phonon transport and scattering channels.
Total syntheses of all tri-oxygenated 16-phytoprostane classes via a common precursor constructed by oxidative cyclization and alkyl–alkyl coupling reactions as the key steps
Authors: Smrček Jakub , Pohl Radek , Jahn Ullrich
Published: October 2017

A parallel total synthesis of 16-F1t-, 16-E1-phytoprostanes and a first synthesis of 16-D1t-phytoprostanes based on a common precursor are described.
Self-condensing reversible complexation-mediated copolymerization for highly branched polymers with in situ formed inimers
Authors: Yang Hongjun , Wang Zhongrui , Cao Lei , Huang Wenyan , Jiang Qiming , Xue Xiaoqiang , Song Yiye , Jiang Bibiao
Published: October 2017

In this work, reversible complexation-mediated polymerization (RCMP) was modified to suit self-condensing vinyl polymerization (SCVP) aimed at the synthesis of highly branched polymers.
Hidden complexity of synergistic roles of Dopa and lysine for strong wet adhesion
Authors: Li Ying , Liang Chao , Gao Ling , Li Shiyu , Zhang Yizhe , Zhang Jiang , Cao Yi
Published: October 2017

Dopa and lysine are widely found in mussel foot proteins and are suggested to play synergistic roles in wet adhesion; yet, the detailed molecular mechanism remains unclear.
Synthesis, structure and optical performance of red-emitting phosphor Ba5AlF13:Mn4+
Authors: Qin Lin , Cai Peiqing , Chen Cuili , Wang Jing , Seo Hyo Jin
Published: October 2017

A novel Ba5AlF13:Mn4+red phosphor which shows significant anti-thermal quenching behavior.
Radical polymers as interfacial layers in inverted hybrid perovskite solar cells
Authors: Zheng Luyao , Mukherjee Sanjoy , Wang Kai , Hay Martha E. , Boudouris Bryan W. , Gong Xiong
Published: October 2017

We report high performance hybrid perovskite solar cells engineered by a UV crosslinkable radical polymer.
Anomalous enhancement in magnetization upon interstitial doping due to spin reversal in magnetic materials
Authors: Singh Nidhi , Anand Kritika , Christopher Nithya , Bhattacharya Amrita , Srivastava A. K.
Published: October 2017

Present work reports a novel strategy for enhancing the magnetic properties employing interstitial doping.
Using Experience Books to Foster the Narrative Skills of English Learners
Authors: Gabas Clariebelle , Wofford Mary Claire , Wood Carla
Published: October 2017

The need to address the language and literacy development of children from culturally and linguistically diverse (CLD) backgrounds continues to rise with the increasing number of English learners (ELs) in schools throughout the United States. One area of concern is the need for culturally sensitive methods of assessment and intervention for ELs with language disorders. Oral language skills are widely considered an essential component of later reading success. Although narratives are commonly used to foster children's oral language skills, narrative development in children from CLD backgrounds can be highly variable. Broader socialization and cultural practices can influence and shape the way children tell stories (Melzi, Schick, & Kennedy, 2011). One approach to facilitate the development of narrative skills in ELs with language disorders is the use of experience books, which are personalized stories that depict daily routines or meaningful events situated from the child's perspective. Experience books can provide a natural foundation of rich linguistic interactions between children and caregivers, increase children's exposure to print and enjoyment of books, and encourage family involvement. The following tutorial will guide speech-language pathologists on how to adapt experience books as culturally sensitive tools to help meet the needs and interests of CLD children and families.
Homoserine and Threonine Peptide Assembly
Authors: Pirrung Michael , Bakas Nicole
Published: October 2017

Drawing on our recent success with reagent-less peptide-bond formation through serine-based assembly reactions in organic solvent, their range has been expanded to threonine and homoserine (an aspartic acid precursor) in the N-terminal peptide. Amino acid scope available at the assembly C-terminus includes bulky residues not amenable to classical ligation methods, such as cysteine-based NCL in aqueous media. The method was used to assemble a snakebite-toxin-neutralizing peptide from opossums.
Racial/Ethnic Differences in Labor Induction in a Contemporary US Cohort: A Retrospective Cohort Study
Authors: Reddy Uma , Huang Chun-Chih , Driggers Rita , Landy Helain , Grantz Katherine , Singh Jasbir
Published: October 2017

Objective To examine labor induction by race/ethnicity and factors associated with disparity in induction.

Study Design This is a retrospective cohort study of 143,634 women eligible for induction ≥24 weeks' gestation from 12 clinical centers (2002–2008). Rates of labor induction for each racial/ethnic group were calculated and stratified by gestational age intervals: early preterm (240/7–336/7), late preterm (340/7–366/7), and term (370/7–416/7 weeks). Multivariable logistic regression examined the association between maternal race/ethnicity and induction controlling for maternal characteristics and pregnancy complications. The primary outcome was rate of induction by race/ethnicity. Inductions that were indicated, non-medically indicated, or without recorded indication were also compared.

Results Non-Hispanic black (NHB) women had the highest percentage rate of induction, 44.6% (p < 0.001). After adjustment, all racial/ethnic groups had lower odds of induction compared with non-Hispanic white (NHW) women. At term, NHW women had the highest percentage rate (45.4%) of non-medically indicated or induction with no indication (p < 0.001).

Conclusion Compared with other racial/ethnic groups, NHW women were more likely to undergo non-medically indicated induction at term. As labor induction may avoid the occurrence of stillbirth, whether this finding explains part of the increased risk of stillbirth for NHB women at term merits further research.
Telemedizinische Assistenzsysteme in der Rehabilitation und Nachsorge –
Anwendungsbereiche und aktuelle Studienergebnisse
Authors: John M. , Einhaus J
Published: October 2017

Die Angebote der medizinischen Rehabilitation müssen flexibler ausgestaltet, stärker auf die
individuellen Bedürfnisse der Betroffenen ausgerichtet und über die Sektorengrenzen hinweg
mit den angrenzenden Bereichen der Akutversorgung und der Nachsorge vernetzt werden. Um
diese Anforderungen erfüllen zu können, ist ein sinnvoller Einsatz Telemedizinischer
Assistenzsysteme sowohl in der eigentlichen Rehabilitations- als auch in der
anschließenden Nachsorgephase erforderlich. Nur dadurch können die angebotenen Leistungen
unter Wahrung einer hohen Behandlungsqualität auf Dauer bezahlbar gestaltet werden.

Dieser Beitrag zeigt auf, in welchen Bereichen Telemedizinische Assistenzsysteme bereits
eingesetzt werden und welche Vorteile sich dadurch ergeben. Dabei wird jeweils sowohl für
die drei großen Bereiche der kardiologischen, neurologischen und orthopädischen
Rehabilitation als auch für sonstige Indikationen ein strukturierter Überblick zur
Studienlage geboten.
Herausnehmbare Implantatkonzepte bei Zahnlosen – Literaturübersicht
Authors: Brandstaeter Sebastian , Tschernitschek Harald , Pott Philipp-Cornelius
Published: October 2017

Konzepte zur herausnehmbaren, implantatgetragenen Versorgung des zahnlosen Kiefers sind stetiger Bestandteil wissenschaftlicher Diskussionen. Dabei beschäftigen sich Experten und Fachgesellschaften in ihren Publikationen, Stellungnahmen und Leitlinien insbesondere mit der notwendigen Anzahl der Implantate, deren Positionierung im Kiefer und der Verwendung unterschiedlicher Verankerungselemente. Ziel dieser Arbeit war es, den derzeitigen Stand der relevanten Fachliteratur zusammenzufassen und bezüglich der Evidenzen zu beurteilen.
Liver Fat Content in People with Pituitary Diseases: Influence of Serum IGF1 Levels
Authors: Nguyen Amandine , Ricolfi Fréderic , Lemogne Brivel , Aho Serge , Lemaire Stéphanie , Bouillet Benjamin , Duvillard Laurence , Denimal Damien , Fourmont Coralie , Loffroy Romaric , Cercueil Jean , Verges Bruno , Petit Jean
Published: October 2017

Non-alcoholic fatty liver disease (NAFLD) is commonly associated with obesity, metabolic syndrome, and type 2 diabetes. NAFLD is also seen in patients with endocrinopathies. However, the relationship between endocrine diseases and the development of NAFLD is not well known. In this study, we set out to determine whether liver fat content (LFC) was associated with IGF1 levels in people with pituitary diseases (PD). Eighty-nine patients with pituitary diseases and 74 healthy controls were included in this study. LFC was measured using MRI. Hepatic steatosis was defined as LFC>5.5%. Patients with PD were older, and had a higher BMI than healthy controls. LFC was significantly higher in people with PD than in controls (6.5% vs. 3.2%; p<0.001). LFC was negatively associated with the IGF1 level. The prevalence of steatosis was higher in PD patients than in controls (36.3% vs. 14.8%; p=0.002). In multivariate analysis, which included patients and controls, the predictive variables for steatosis were age, BMI and IGF1 levels, whereas the presence of pituitary diseases and gender were not associated with steatosis. Our data showed that LFC was strongly associated with IGF1 levels. These results suggest that steatosis associated with PD is probably a consequence of a low IGF1 level in these patients.
Dilatancy and compaction effects on the submerged granular column collapse
Authors: Wang Chun , Wang Yongqi , Peng Chong , Meng Xiannan
Published: October 2017

The effects of dilatancy on the collapse dynamics of granular materials in air or in a liquid are studied experimentally and numerically. Experiments show that dilatancy has a critical effect on the collapse of granular columns in the presence of an ambient fluid. Two regimes of the collapse, one being quick and the other being slow, are observed from the experiments and the underlying reasons are analyzed. A two-fluid smoothed particle hydrodynamics model, based on the granular-fluid mixture theory and the critical state theory, is employed to investigate the complex interactions between the solid particles and the ambient water. It is found that dilatancy, resulting in large effective stress and large frictional coefficient between solid particles, helps form the slow regime. Small permeability, representing large inter-phase drag force, also retards the collapse significantly. The proposed numerical model is capable of reproducing these effects qualitatively.
Class-A mode-locked lasers: Fundamental solutions
Authors: Kovalev Anton V. , Viktorov Evgeny A.
Published: October 2017

We consider a delay differential equation (DDE) model for mode-locked operation in class-A semiconductor lasers containing both gain and absorber sections. The material processes are adiabatically eliminated as these are considered fast in comparison to the delay time for a long cavity device. We determine the steady states and analyze their bifurcations using DDE-BIFTOOL [Engelborghs et al., ACM Trans. Math. Software 28, 1 (2002)]. Multiple forms of coexistence, transformation, and hysteretic behavior of stable steady states and fundamental periodic regimes are discussed in bifurcation diagrams.
Performance evaluation of a permanent ring magnet based helicon plasma source for negative ion source research
Authors: Pandey Arun , Bandyopadhyay M. , Sudhir Dass , Chakraborty A.
Published: October 2017

Helicon wave heated plasmas are much more efficient in terms of ionization per unit power consumed. A permanent magnet based compact helicon wave heated plasma source is developed in the Institute for Plasma Research, after carefully optimizing the geometry, the frequency of the RF power, and the magnetic field conditions. The HELicon Experiment for Negative ion-I source is the single driver helicon plasma source that is being studied for the development of a large sized, multi-driver negative hydrogen ion source. In this paper, the details about the single driver machine and the results from the characterization of the device are presented. A parametric study at different pressures and magnetic field values using a 13.56 MHz RF source has been carried out in argon plasma, as an initial step towards source characterization. A theoretical model is also presented for the particle and power balance in the plasma. The ambipolar diffusion process taking place in a magnetized helicon plasma is also discussed.
Self-consistent self-interaction corrected density functional theory calculations for atoms using Fermi-Löwdin orbitals: Optimized Fermi-orbital descriptors for Li–Kr
Authors: Kao Der-you , Withanage Kushantha , Hahn Torsten , Batool Javaria , Kortus Jens , Jackson Koblar
Published: October 2017

In the Fermi-Löwdin orbital method for implementing self-interaction corrections (FLO-SIC) in density functional theory (DFT), the local orbitals used to make the corrections are generated in a unitary-invariant scheme via the choice of the Fermi orbital descriptors (FODs). These are M positions in 3-d space (for an M-electron system) that can be loosely thought of as classical electron positions. The orbitals that minimize the DFT energy including the SIC are obtained by finding optimal positions for the FODs. In this paper, we present optimized FODs for the atoms from Li–Kr obtained using an unbiased search method and self-consistent FLO-SIC calculations. The FOD arrangements display a clear shell structure that reflects the principal quantum numbers of the orbitals. We describe trends in the FOD arrangements as a function of atomic number. FLO-SIC total energies for the atoms are presented and are shown to be in close agreement with the results of previous SIC calculations that imposed explicit constraints to determine the optimal local orbitals, suggesting that FLO-SIC yields the same solutions for atoms as these computationally demanding earlier methods, without invoking the constraints.
Local-metrics error-based Shepard interpolation as surrogate for highly non-linear material models in high dimensions
Authors: Lorenzi Juan M. , Stecher Thomas , Reuter Karsten , Matera Sebastian
Published: October 2017

Many problems in computational materials science and chemistry require the evaluation of expensive functions with locally rapid changes, such as the turn-over frequency of first principles kinetic Monte Carlo models for heterogeneous catalysis. Because of the high computational cost, it is often desirable to replace the original with a surrogate model, e.g., for use in coupled multiscale simulations. The construction of surrogates becomes particularly challenging in high-dimensions. Here, we present a novel version of the modified Shepard interpolation method which can overcome the curse of dimensionality for such functions to give faithful reconstructions even from very modest numbers of function evaluations. The introduction of local metrics allows us to take advantage of the fact that, on a local scale, rapid variation often occurs only across a small number of directions. Furthermore, we use local error estimates to weigh different local approximations, which helps avoid artificial oscillations. Finally, we test our approach on a number of challenging analytic functions as well as a realistic kinetic Monte Carlo model. Our method not only outperforms existing isotropic metric Shepard methods but also state-of-the-art Gaussian process regression.
Influence of Kohn singularity on the occurrence scattering time in degenerate quantum collisional plasmas
Authors: Lee Myoung-Jae , Jung Young-Dae
Published: October 2017

The influence of Kohn singularity on the occurrence scattering time for the electron-ion interaction is investigated in degenerate quantum collisional plasmas. The first-order eikonal analysis is used to obtain the scattering amplitude and the occurrence scattering time. The result shows that the Friedel oscillation due to the Kohn singularity suppresses the advance phenomena of occurrence scattering time in both forward and backward scattering domains. It is shown that the increase of plasmon energy would reduce the time advance for both forward and backward scattering domains. However, the increase of Fermi energy would enhance the phenomena of time advance. It is also found that the time advance with high collision frequency is larger than that with low collision frequency for the forward scattering domain and vice versa for the backward scattering domain. We have shown that the time advance is stronger in general for the forward scattering domain than that for the backward scattering domain.
Evidence of a topological Hall effect in Eu1−xSmxTiO3
Authors: Ahadi Kaveh , Galletti Luca , Stemmer Susanne
Published: October 2017

We report on the observation of a possible topological Hall effect in thin films of the itinerant ferromagnet Eu1−xSmxTiO3. EuTiO3 and Eu0.955Sm0.045TiO3 films were grown by molecular beam epitaxy. The EuTiO3 film is insulating. The Hall resistivity of the Eu0.955Sm0.045TiO3 films exhibits the anomalous Hall effect below the Curie temperature of ∼5 K and additional features that appear at 2 K. It is shown that these features are magnetic in origin and consistent with the topological Hall effect seen in material systems with topologically nontrivial spin textures such as skyrmions. The results open up interesting possibilities for epitaxial hybrid heterostructures that combine topological magnetic states, tunable carrier densities, and other phenomena.
Construction and evaluation of an ultrahigh-vacuum-compatible sputter deposition source
Authors: Lackner Peter , Choi Joong Il Jake , Diebold Ulrike , Schmid Michael
Published: October 2017

A sputter deposition source for the use in ultrahigh vacuum (UHV) is described, and some properties of the source are analyzed. The operating principle is based on the design developed by Mayr et al. [Rev. Sci. Instrum. 84, 094103 (2013)], where electrons emitted from a filament ionize argon gas and the Ar+ ions are accelerated to the target. In contrast to the original design, two grids are used to direct a large fraction of the Ar+ ions to the target, and the source has a housing cooled by liquid nitrogen to reduce contaminations. The source has been used for the deposition of zirconium, a material that is difficult to evaporate in standard UHV evaporators. At an Ar pressure of 9×10−6 mbar in the UHV chamber and moderate emission current, a highly reproducible deposition rate of ≈1 ML in 250 s was achieved at the substrate (at a distance of ≈50 mm from the target). Higher deposition rates are easily possible. X-ray photoelectron spectroscopy shows a high purity of the deposited films. Depending on the grid voltages, the substrate gets mildly sputtered by Ar+ ions; in addition, the substrate is also reached by electrons from the negatively biased sputter target.
Crossing conditions in coupled cluster theory
Authors: Kjønstad Eirik F. , Myhre Rolf H. , Martínez Todd J. , Koch Henrik
Published: October 2017

We derive the crossing conditions at conical intersections between electronic states in coupled cluster theory and show that if the coupled cluster Jacobian matrix is nondefective, two (three) independent conditions are correctly placed on the nuclear degrees of freedom for an inherently real (complex) Hamiltonian. Calculations using coupled cluster theory on a 21A′/31A′ conical intersection in hypofluorous acid illustrate the nonphysical artifacts associated with defects at accidental same-symmetry intersections. In particular, the observed intersection seam is folded about a space of the correct dimensionality, indicating that minor modifications to the theory are required for it to provide a correct description of conical intersections in general. We find that an accidental symmetry allowed 11A″/21A″ intersection in hydrogen sulfide is properly described, showing no artifacts as well as linearity of the energy gap to first order in the branching plane.
Stability and carrier mobility of organic-inorganic hybrid perovskite CH3NH3PbI3 in two-dimensional limit
Authors: Huang Kui , Lai Kang , Yan Chang-Lin , Zhang Wei-Bing
Published: October 2017

Recently, atomically thin organic-inorganic hybrid perovskites have been synthesized experimentally, which opens up new opportunities for exploring their novel properties in the 2D limit. Based on the comparative density functional theory calculation with and without spin-orbit coupling effects, the stability, electronic structure, and carrier mobility of the two-dimensional organic-inorganic hybrid perovskites MAPbI3 (MA = CH3NH3) have been investigated systemically. Two single-unit-cell-thick 2D MAPbI3 terminated by PbI2 and CH3NH3I are constructed, and their thermodynamic stabilities are also evaluated using the first-principles constrained thermodynamics method. Our results indicate that both 2D MAPbI3 with different terminations can be stable under certain conditions and have a suitable direct bandgap. Moreover, they are also found to have termination-dependent band edge and carrier mobility. The acoustic-phonon-limited carrier mobilities estimated using the deformation theory and effective mass approximation are on the order of thousands of square centimeters per volt per second and also highly anisotropic. These results indicate that 2D MAPbI3 are competitive candidates for low-dimensional photovoltaic applications.
Investigating the origin of third harmonic generation from diabolo optical antennas
Authors: Shi Liping , Andrade José R. C. , Kim Hyunwoong , Han Seunghwoi , Nicolas Rana , Franz Dominik , Boutu Willem , Heidenblut Torsten , Segerink Frans B. , Bastiaens Bert , Merdji Hamed , Kim Seung-Woo , Morgner Uwe , Kovačev Milutin
Published: October 2017

We propose to use diabolo nanoantennas for experimentally investigating the origin of the enhanced third harmonic generation by localized surface plasmon polaritons. In such a geometry, the opposing apexes of bowties are electrically connected by a thin gold nanorod, which has two important functions in discriminating the point of harmonic generation. First, the inserted gold nanorod shifts the field enhancement area to be far away from the dielectric substrate material. Next, the accumulation of free charges at the adjacent bowtie tips produces a strong electric field inside the gold nanorod. The diabolo nanoantennas allow us to examine the contribution of the bare gold susceptibility to the third harmonic conversion. Our results reveal that the bare gold does not significantly enhance the harmonic generation at high pump intensity. From this, we deduce that in regular bowtie antennas, the enhanced harmonic photons mainly arise from the substrate sapphire that is located in the feedgap of the bowtie, where the electric near-field is significantly enhanced by the localized surface plasmons.
Engineering the magnetic anisotropy axes in epitaxial half-Heusler NiMnSb by Pt and Ta capping
Authors: Gerhard F. , Baussenwein M. , Scheffler L. , Kleinlein J. , Gould C. , Molenkamp L. W.
Published: October 2017

The magnetic anisotropy in NiMnSb has been found to be highly sensitive to layer parameters, such as Mn concentration or thickness. Here, we report on the magnetic anisotropy of thin epitaxial single crystal quality NiMnSb films (3–40 nm) in combination with different capping layer materials, Ru, Pt, and Ta. We observe that the easy axis of the magnetic anisotropy is forced into the [11¯0] crystal direction for Pt capped and into the [110] crystal direction for Ta capped NiMnSb, irrespective of the original anisotropy of the NiMnSb film. This effect is independent of the thickness of the capping layer and even present in multilayers with a Cu interlayer (few nanometers) between the NiMnSb and Pt cap, indicating that it is not related to interface chemistry and possibly pointing to it originating from the strong spin-orbit coupling in the capping layers.
Second sound tracking system
Authors: Yang Jihee , Ihas Gary G. , Ekdahl Dan
Published: October 2017

It is common that a physical system resonates at a particular frequency, whose frequency depends on physical parameters which may change in time. Often, one would like to automatically track this signal as the frequency changes, measuring, for example, its amplitude. In scientific research, one would also like to utilize the standard methods, such as lock-in amplifiers, to improve the signal to noise ratio. We present a complete He ii second sound system that uses positive feedback to generate a sinusoidal signal of constant amplitude via automatic gain control. This signal is used to produce temperature/entropy waves (second sound) in superfluid helium-4 (He ii). A lock-in amplifier limits the oscillation to a desirable frequency and demodulates the received sound signal. Using this tracking system, a second sound signal probed turbulent decay in He ii. We present results showing that the tracking system is more reliable than those of a conventional fixed frequency method; there is less correlation with temperature (frequency) fluctuation when the tracking system is used.
The number of eigenvalues of the matrix Schrödinger operator on the half line with general boundary conditions
Authors: Weder Ricardo
Published: October 2017

We prove a bound, of the Bargmann-Birman-Schwinger type, on the number of eigenvalues of the matrix Schrödinger operator on the half line, with the most general self-adjoint boundary condition at the origin, and with selfadjoint matrix potentials that are integrable and have a finite first moment.
A new experimental scheme for nuclear γ-resonance time-domain interferometry
Authors: Caporaletti F. , Chumakov A. I. , Rüffer R. , Monaco G.
Published: October 2017

Time-domain interferometry (TDI) based on nuclear resonant scattering of synchrotron radiation by Mössbauer nuclei is a promising technique to study slow dynamics at the interatomic length scale. In order to improve the efficiency of this technique, a new TDI scheme is developed involving the use of a nuclear absorber with a two-line energy spectrum combined with a single-line spectrum. Different from other TDI setups, the issue of external vibrations is much reduced since the two absorbers are at rest and no velocity transducer is used. This allows measuring beating patterns with satisfying statistical accuracy and contrast up to 350 ns. We report here the characterization of the experimental setup necessary for the implementation of this new scheme. The model required for the description of the beating pattern produced by a three-line spectrum system is also discussed in detail. Finally, we report some results for the dynamics of the prototypical glass-former ortho-terphenyl to demonstrate the possibilities offered by this new scheme.
Laboratory simulation of the formation of an ionospheric depletion using Keda Space Plasma EXperiment (KSPEX)
Authors: Yu Pengcheng , Liu Yu , Cao Jinxiang , Lei Jiuhou , Zhang Zhongkai , Zhang Xiao
Published: October 2017

In the work, the formation of an ionospheric depletion was simulated in a controlled laboratory plasma. The experiment was performed by releasing chemical substance sulfur hexafluoride (SF6) into the pure argon discharge plasma. Results indicate that the plasma parameters change significantly after release of chemicals. The electron density is nearly depleted due to the sulfur hexafluoride-electron attachment reaction; and the electron temperature and space potential experience an increase due to the decrease of the electron density. Compared to the traditional active release experiments, the laboratory scheme can be more efficient, high repetition rate and simpler measurement of the varying plasma parameter after chemical releasing. Therefore, it can effective building the bridge between the theoretical work and real space observation.
High aspect ratio silver grid transparent electrodes using UV embossing process
Authors: Kim Dong Jin , Lim Mikyung , Lee Seung S. , Kim Jin-Ha
Published: October 2017

This study presents a UV embossing process to fabricate high aspect ratio silver grid transparent electrodes on a polymer film. Transparent electrodes with a high optical transmittance (93 %) and low sheet resistance (4.6 Ω/sq) were fabricated without any high temperature or vacuum processes. The strong adhesion force between the UV resin and the silver ink enables the fabrication of silver microstructures with an aspect ratio higher than 3. The high aspect ratio results in a low sheet resistance while maintaining a high optical transmittance. Multi-layer transparent electrodes were fabricated by repeating the proposed UV process. Additionally, a large-area of 8-inch touch panel was fabricated with the proposed UV process. The proposed UV process is a relatively simple and low cost process making it suitable for large-area production as well as mass production.
NTRC-dependent redox balance of 2-Cys peroxiredoxins is needed for optimal function of the photosynthetic apparatus
Authors: Pérez-Ruiz Juan Manuel , Naranjo Belén , Ojeda Valle , Guinea Manuel , Cejudo Francisco Javier
Published: October 2017

Significance

Chloroplasts harbor a complex redox network formed by two systems, the FTR- thioredoxins (Trxs), which relies on photoreduced ferredoxin (Fd), and the NADPH-dependent Trx reductase C NTRC. Thus, an important issue in chloroplast biology is to establish the relationship between these redox pathways. Here we propose that the Fd-FTR-Trxs and NTRC redox systems are integrated via the redox balance of 2-Cys peroxiredoxins (Prxs), which therefore has a key role in chloroplast function. NTRC controls the redox balance of 2-Cys Prxs, which maintains the reducing capacity of the pool of chloroplast Trxs and, consequently, proper regulation of photosynthetic carbon assimilation enzymes. Therefore, redox regulation of chloroplast enzymes and hydrogen peroxide reduction are linked by the action of the NTRC-2-Cys Prxs system.
Intercellular mRNA trafficking via membrane nanotube-like extensions in mammalian cells
Authors: Haimovich Gal , Ecker Christopher M. , Dunagin Margaret C. , Eggan Elliott , Raj Arjun , Gerst Jeffrey E. , Singer Robert H.
Published: October 2017

Significance

mRNA molecules convey genetic information within cells, beginning from genes in the nucleus to ribosomes in the cell body, where they are translated into proteins. Here we show a mode of transferring genetic information from one cell to another. Contrary to previous publications suggesting that mRNAs transfer via extracellular vesicles, we provide visual and quantitative data showing that mRNAs transfer via membrane nanotubes and direct cell-to-cell contact. We predict that this process has a major role in regulating local cellular environments with respect to tissue development and maintenance and cellular responses to stress, interactions with parasites, tissue transplants, and the tumor microenvironment.
Ultraaccurate genome sequencing and haplotyping of single human cells
Authors: Chu Wai Keung , Edge Peter , Lee Ho Suk , Bansal Vikas , Bafna Vineet , Huang Xiaohua , Zhang Kun
Published: October 2017

Significance

Accurate sequencing and haplotyping of diploid genomes of single cells are intrinsically difficult due to the small amount of starting materials and limited read lengths of current DNA sequencing methods. In SISSOR (single-stranded sequencing using microfluidic reactors), we aim to improve sequencing accuracy and haplotype assembly by taking advantage of the redundant complementary sequence information in the double-stranded DNA and by partitioning megabase-size single-stranded DNA fragments from the homologous chromosome pairs into multiple compartments for amplification by MDA (multiple displacement amplification) and subsequent sequencing using short-read DNA sequencing platforms. We report the demonstration of the most accurate single-cell genome sequencing to date with data from three single human cells. Our approach can simultaneously provide higher accuracy and longer haplotypes than existing approaches.
Necroptosis controls NET generation and mediates complement activation, endothelial damage, and autoimmune vasculitis
Authors: Schreiber Adrian , Rousselle Anthony , Becker Jan Ulrich , von Mässenhausen Anne , Linkermann Andreas , Kettritz Ralph
Published: October 2017

Significance

In this report, we provide evidence of a mechanistic link between antineutrophil cytoplasmic antibody (ANCA)-induced neutrophil activation, regulated necrosis (necroptosis), generation of neutrophil extracellular traps, complement activation, and endothelial cell damage with consecutive vasculitis and glomerulonephritis in autoimmune ANCA-induced vasculitis (AAV). We now show that inhibition of necroptosis-inducing kinases completely prevents ANCA vasculitis and establish a link to activation of the complement system. We suggest that these findings significantly extend our understanding of the pathogenesis of AAV and especially the tight regulation of neutrophil cell death therein. In addition, specific necroptosis inhibitors are currently being evaluated in clinical studies and can possibly complement existing therapeutic strategies in AAV.
Human hippocampal theta power indicates movement onset and distance travelled
Authors: Bush Daniel , Bisby James A. , Bird Chris M. , Gollwitzer Stephanie , Rodionov Roman , Diehl Beate , McEvoy Andrew W. , Walker Matthew C. , Burgess Neil
Published: October 2017

Significance

Rodent hippocampal theta-band oscillations are observed throughout translational movement, implicating theta in the encoding of self-motion. Interestingly, increases in theta power are particularly prominent around movement onset. Here, we use intracranial recordings from epilepsy patients navigating in a desktop virtual reality environment to demonstrate that theta power is also increased in the human hippocampus around movement onset and throughout the remainder of movement. Importantly, these increases in theta power are greater both before and during longer paths, directly implicating human hippocampal theta in the encoding of translational movement. These findings help to reconcile previous studies of rodent and human hippocampal theta oscillations and provide additional insight into the mechanisms of spatial navigation in the human brain.
Dual origin of enteric neurons in vagal Schwann cell precursors and the sympathetic neural crest
Authors: Espinosa-Medina Isabel , Jevans Ben , Boismoreau Franck , Chettouh Zoubida , Enomoto Hideki , Müller Thomas , Birchmeier Carmen , Burns Alan J. , Brunet Jean-François
Published: October 2017

Significance

The enteric nervous system of vertebrates arises mostly from a rostral portion of the neural crest, encapsulated by the term “vagal.” We show that the “vagal crest” is in fact a juxtaposition of two completely different types of cells: Schwann cell precursors associated with the vagus nerve, which provide esophageal neurons, and the rostral-most trunk crest, which also forms sympathetic ganglia and locally overshoots the aorta to colonize most of the gut. Moreover, in line with the known dependency of both Schwann cell precursors and trunk crest on the ErbB3 tyrosine receptor kinase and its ligand Neuregulin1, we discover that the enteric nervous system is also atrophic in
ErbB3
mutants, with potential relevance to Hirschsprung disease, a congenital hypoganglionosis.
A unique surface on Pat1 C-terminal domain directly interacts with Dcp2 decapping enzyme and Xrn1 5′–3′ mRNA exonuclease in yeast
Authors: Charenton Clément , Gaudon-Plesse Claudine , Fourati Zaineb , Taverniti Valerio , Back Régis , Kolesnikova Olga , Séraphin Bertrand , Graille Marc
Published: October 2017

Significance

Control of mRNA synthesis and decay is crucial for cells to adapt to their environment and for proper development. The 5′ end of eukaryotic mRNAs is modified by a structure called cap that protects them from rapid and uncontrolled decay. During mRNA decay, this cap is removed by a specialized and finely regulated multiprotein factory called decapping complex. Our results support a model in which the two major enzymes responsible for mRNA decapping (Dcp2) and decay (Xrn1) are sequentially recruited to mRNAs by the same surface from Pat1, a scaffolding protein central for decapping. As this Pat1 region is important for growth and specific to fungi, this is a potential target for the development of drugs against pathogenic yeasts.
Algorithm for cellular reprogramming
Authors: Ronquist Scott , Patterson Geoff , Muir Lindsey A. , Lindsly Stephen , Chen Haiming , Brown Markus , Wicha Max S. , Bloch Anthony , Brockett Roger , Rajapakse Indika
Published: October 2017

Significance

Reprogramming the human genome toward any desirable state is within reach; application of select transcription factors drives cell types toward different lineages in many settings. We introduce the concept of data-guided control in building a universal algorithm for directly reprogramming any human cell type into any other type. Our algorithm is based on time series genome transcription and architecture data and known regulatory activities of transcription factors, with natural dimension reduction using genome architectural features. Our algorithm predicts known reprogramming factors, top candidates for new settings, and ideal timing for application of transcription factors. This framework can be used to develop strategies for tissue regeneration, cancer cell reprogramming, and control of dynamical systems beyond cell biology.
Framework and resource for more than 11,000 gene-transcript-protein-reaction associations in human metabolism
Authors: Ryu Jae Yong , Kim Hyun Uk , Lee Sang Yup
Published: October 2017

Significance

Alternative splicing is a regulatory mechanism by which multiple protein isoforms can be generated from one gene. Despite its biological importance, there has been no systematic approach that facilitates characterizing functional roles of protein isoforms in human metabolism. To this end, we present a systematic framework for the generation of gene-transcript-protein-reaction associations (GeTPRA) in human metabolism. The framework involves a generic human genome-scale metabolic model (GEM) that is an excellent framework to investigate genotype–phenotype associations. We show that a biochemically consistent and transcript-level data-compatible human GEM can be used to generate GeTPRA, which can be deployed to further upgrade the human GEM. Personal GEMs generated with GeTPRA information enabled more accurate simulation of cancer metabolism and prediction of anticancer targets.