bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptive synchronisation for a class of output‐coupling complex networks with output feedback nodes
Authors: Li Qingbo , Guo Jin , Sun Chang‐Yin , Wu Yuanyuan
Published: September 2017

This study investigates the synchronisation problem of a class of output‐coupling complex networks whose nodes are in the output feedback form and contain unknown non‐linear functions. To tackle the unknown parameters in the non‐linear nodes, adaptive dynamic output feedback controllers are designed. By employing the linear matrix inequality technique, several sufficient conditions are derived to ensure the global asymptotic synchronisation for the resulting closed‐loop systems. An illustrative numerical example is given to show the effectiveness of the main results.
State‐feedback controller design for disturbance decoupling of Boolean control networks
Authors: Zou Yunlei , Zhu Jiandong , Liu Yurong
Published: September 2017

This paper investigates the disturbance decoupling problem for Boolean control networks. Firstly, using the matrix semi‐tensor product, the logical dynamic equations of Boolean control networks are converted into discrete time linear equations. Secondly, the solvability of the disturbance decoupling problem is analyzed based on the structure matrices of BCNs, and a method for design state‐feedback controllers is put forward to deal with this problem. Two necessary and sufficient conditions for the disturbance decoupling problem of BCNs are obtained. Then an algorithm is provided to design controllers for calculating the disturbance decoupling forms of Boolean control networks. Finally, an illustrative example is given to describe the proposed algorithm.
Boundary supply capability for distribution systems: concept, indices and calculation
Authors: Xiao Jun , Zhang Miaomiao , Bai Linquan , She Buxin , Zhang Baoqiang
Published: September 2017

This study proposes the concept, indices and calculation method of boundary supply capability (BSC), which is the first capability curve for distribution networks. BSC describes the supply capability of distribution networks under various loading conditions. First, BSC is defined as a total load of an operating point on the security boundary. The BSC set of all boundary points represents the overall capability of a distribution network; while the total supply capability is the maximum value in a BSC set. Second, a method is proposed to calculate the BSC and its related indices. This method consists of three steps: (i) obtain a set of boundary points by sampling, (ii) calculate the BSC value of each point, and (iii) analyse the BSC set and obtain the following information: sorted BSC curve, BSC proportion distribution curve, mean value, lower bound, upper bound and so on. Finally, extended IEEE‐RTBS‐BUS4 cases are used to illustrate the proposed concept and demonstrate the effectiveness of the proposed BSC method. It is demonstrated that BSC can describe the supply capability distribution of distribution networks under N  − 1 security comprehensively.
Junction temperature estimation of IGBT module via a bond wires lift‐off independent parameter VgE‐np
Authors: Peng Yingzhou , Zhou Luowei , Du Xiong , Sun Pengju , Wang Kaihong , Cai Jie
Published: September 2017

An electrical method for junction temperature estimation of insulated‐gate bipolar transistors (IGBTs) is presented in this study. Owing to the parasitic inductance between bond wire and main emitter terminal LE. The temperature‐dependent falling collector current during turn‐off transition would cause a negative voltage drop in the gate‐main emitter voltage waveform vgE. Therefore, this negative voltage drop VgE‐np is proportional to the junction temperature. A double‐pulse test circuit is developed to verify the accuracy and feasibility of the proposed method. The impacts of collector–emitter voltage Vce, collector current Ic and bond‐wires cut‐off are also be discussed theoretically and experimentally. The experimental results show that the proposed VgE‐np has a linear relationship with junction temperature as theoretical analysis and it is a bond‐wires cut‐off independent parameter in some special test point, which offers an effective way to estimate junction temperature without package destruction. The advantages of the proposed method include good linearity, bond‐wires failure immunity and adequate sensitivity with junction temperature.
XMM-Newton X-ray and HST weak gravitational lensing study of the extremely X-ray luminous galaxy cluster Cl J120958.9+495352 (z = 0.902)
Authors: Thölken Sophia , Schrabback Tim , Reiprich Thomas H. , Lovisari Lorenzo , Allen Steven W. , Hoekstra Henk , Applegate Douglas , Buddendiek Axel , Hicks Amalia
Published: September 2017

Context. Observations of relaxed, massive, and distant clusters can provide important tests of standard cosmological models, for example by using the gas mass fraction. To perform this test, the dynamical state of the cluster and its gas properties have to be investigated. X-ray analyses provide one of the best opportunities to access this information and to determine important properties such as temperature profiles, gas mass, and the total X-ray hydrostatic mass. For the last of these, weak gravitational lensing analyses are complementary independent probes that are essential in order to test whether X-ray masses could be biased.

Aims. We study the very luminous, high redshift (z = 0.902) galaxy cluster Cl J120958.9+495352 using XMM-Newton data. We measure global cluster properties and study the temperature profile and the cooling time to investigate the dynamical status with respect to the presence of a cool core. We use Hubble Space Telescope (HST) weak lensing data to estimate its total mass and determine the gas mass fraction.

Methods. We perform a spectral analysis using an XMM-Newton observation of 15 ks cleaned exposure time. As the treatment of the background is crucial, we use two different approaches to account for the background emission to verify our results. We account for point spread function effects and deproject our results to estimate the gas mass fraction of the cluster. We measure weak lensing galaxy shapes from mosaic HST imaging and select background galaxies photometrically in combination with imaging data from the William Herschel Telescope.

Results. The X-ray luminosity of Cl J120958.9+495352 in the 0.1–2.4 keV band estimated from our XMM-Newton data is LX = (13.4−1.0+1.2) × 1044 erg/s and thus it is one of the most X-ray luminous clusters known at similarly high redshift. We find clear indications for the presence of a cool core from the temperature profile and the central cooling time, which is very rare at such high redshifts. Based on the weak lensing analysis, we estimate a cluster mass of M500 / 1014 M⊙ = 4.4−2.0+2.2(star.) ± 0.6(sys.) and a gas mass fraction of fgas,2500 = 0.11−0.03+0.06 in good agreement with previous findings for high redshift and local clusters.
Long-Term Outcomes of Small for Gestational Age Twins Born at 34 Weeks or Later
Authors: Herlihy Nola , Odom Elizabeth , Cohen Natalie , Stroustrup Annemarie , Rebarber Andrei , Fox Nathan
Published: September 2017

Objective This article aims to compare long-term neurodevelopmental and health outcomes of twins born at 34 weeks or later, based on the presence of small for gestational age (SGA).

Study Design This study is a mail-based survey of twin gestations delivered by a single practice. We compared twins with and without SGA delivered at ≥34 weeks. There were two primary outcomes for this study: a composite of major adverse outcomes (death; cerebral palsy; necrotizing enterocolitis; chronic renal, heart, or lung disease) and a composite of minor adverse outcomes (learning disability, speech therapy, occupational therapy, physical therapy). Regression analysis was performed to control for clustering of outcomes within twin pairs.

Results A total of 712 children were included. Comparing twins with birthweights <10% to ≥10%, there were no significant differences in rates of composite major morbidities (3.2 vs. 1.4%, p = 0.109) or composite minor morbidities (43.6 vs. 39.3%, p = 0.279). Comparing twins with birthweights <5% to ≥5%, the rates of major morbidities were low in both groups, but significantly higher in the group with birthweights <5% (4.4 vs. 1.6%, p = 0.046). There were no significant differences seen in the composite minor morbidities (46.7 vs. 39.7%, p = 0.134). Twins with birthweights <5% were significantly more likely to have childhood cardiac disease (2.9 vs. 0.7%, p = 0.041).

Conclusion Twins with SGA <10% born at ≥34 weeks have similar long-term neurodevelopmental and health outcomes compared with twins with normal birthweights. Birthweight less than 5th percentile is associated with an increased risk of major morbidity, specifically cardiac disease, but the absolute risk is low.
Organerhaltende Therapie beim Peniskarzinom
Authors: Protzel Chris , Hakenberg Oliver W.
Published: September 2017

Die organerhaltende Therapie des Peniskarzinoms erscheint als eine sichere Methodik in der Behandlung des Primärtumors. Sie spielt aufgrund
der enormen psychoonkologischen und sozialen Tragweite der Chirurgie am äußeren Genitale eine entscheidende Rolle für die Lebensqualität der
Patienten. Die organerhaltende Therapie sollte stadienadaptiert erfolgen. Eine intraoperative Kontrolle der Tumorfreiheit der Schnittränder
erscheint effizient.
Ein verstrahltes Leben
Authors: Hardinghaus Christian
Published: September 2017

19 Folgen dieser chronologisch aufgebauten Serie hat es gedauert, bis wir heute die erste Frau vorstellen können. Und dabei ist Marie Curie
keine Ärztin, hat sich aber in besonderem Maße für die Medizin verdient gemacht. Gleichzeitig stellt Marie Curie auch die erste weibliche
Nobelpreisträgerin. Außerdem ist sie bis heute die einzige Wissenschaftlerin, die diesen bedeutenden Preis gleich zweimal in
unterschiedlichen Disziplinen gewinnen konnte. 1903 gemeinsam mit ihrem Mann Pierre den Nobelpreis für Physik und 1911 den für Chemie.
Verliehen für ihre Entdeckungen der chemischen Elemente Polonium und Radium. Curie prägte auch den Begriff Radioaktivität. Die Polin
behandelte als Radiologin verwundete Soldaten im Ersten Weltkrieg, setzte sich für die Förderung von Frauen in der Wissenschaft ein und
wagte Versuche, mit denen sie ihr eigenes Leben aufs Spiel setzte. Mit nur 67 Jahren starb Curie an den Langzeitfolgen durch radioaktive
Strahlung.
Effects of Aldosterone on Chemerin Expression And Secretion in 3T3-L1 Adipocytes
Authors: Ma Junhua , Sun Fei , Wang Jingnan , Jiang He , Lu Jiancan , Wang Xing , Zhang Jichen , Shi Chao , You Wen , Li Xiangqi , Zhu Hongling , Gu Mingjun
Published: September 2017

Aldosterone plays a pivotal role in the pathogenesis of metabolic syndrome and cardiovascular disease; however, the underlying mechanisms have not been clarified. Chemerin has been characterized as an adipokine with crucial roles in obesity-associated disorders and cardiovascular homeostasis. The aim of the present study was to investigate the direct effects of aldosterone on chemerin expression and secretion in 3T3-L1 adipocytes and to identify the potential signalling pathways involved. Chemerin mRNA levels were measured using real-time PCR, whereas the levels of secreted chemerin in the culture media were determined using ELISA. Treatment with aldosterone induced time- and dose-dependent increases of chemerin gene expression and protein secretion, and effect that was mediated through the mineralocorticoid receptor. Signalling studies suggested that the NF-κB pathway is involved in aldosterone-induced chemerin expression. Taken together, our data demonstrate a direct interaction between aldosterone and chemerin in adipocytes, which may be an underlying mechanism linking aldosterone-associated metabolic abnormalities and cardiovascular disease.
Improvement of Radiological Teaching – Effects of Focusing of Learning Targets and Increased Consideration of Learning Theory Knowledge
Authors: Wirth Stefan , William York-Alexander , Paolini Marco , Wirth Kathrin , Maxien Daniel , Reiser Maximilian , Fischer Martin
Published: September 2017

Purpose Based on evaluation and examination results of students, a necessity for improvement of so far purely instructor-based radiological teaching at the local institution was determined. Aim of our study was to use one out of eight seminars to exemplify adaptation of the teaching concept according to learning theory knowledge, to determine the resulting effects and to interpret them.

Materials and methods The institutional review board approved the prospective study of the seminar conversion, which was performed after the end of the winter semester 2015/2016. Didactically, this included a course split into online preparation, attendance phase and online follow-up with integration of interactive scaffolding, practice-oriented clinical teaching according to Stanford, Peyton skills transfer and extensive feedback into the attendance phase. At the beginning and at the end of each course, each student filled in identical, standardized questionnaires (n = 256 before and after conversion) using a 5-point Likert scale (1: very good; to 5: deficient) and additionally answered two randomly chosen written examination questions from a content-adapted questionnaire pool of the last five years. For statistical evaluation, the Mann-Whitney U-Test was used for evaluation data and Fisher's Exact test for exam questions.

Results Before/after conversion, the subjective total evaluation score of students was 3.22 (mean value) ± 1.51 (standard deviation) / 1.66 ± 0.78 (p < 0.001) and the objective proportion of correctly answered examination questions in the respective cohort at the beginning of the seminar 37.7/53.9 % and at the end of the seminar 55.1/84.6 % (p < 0.001).

Conclusion The conversion of the test seminar resulted in both a better evaluation of the teaching unit by the students (evaluation) and a considerably higher rate of correctly answered examination questions from past state examinations (learning success). This supports transferring the concept to comparable teaching units.

Key points 

Citation Format
Three-body interactions and the elastic constants of hcp solid 4He
Authors: Barnes Ashleigh L. , Hinde Robert J.
Published: September 2017

The effect of three-body interactions on the elastic properties of hexagonal close packed solid 4He is investigated using variational path integral (VPI) Monte Carlo simulations. The solid’s nonzero elastic constants are calculated, at T = 0 K and for a range of molar volumes from 7.88 cm3/mol to 20.78 cm3/mol, from the bulk modulus and the three pure shear constants C0, C66, and C44. Three-body interactions are accounted for using our recently reported perturbative treatment based on the nonadditive three-body potential of Cencek et al. Previous studies have attempted to account for the effect of three-body interactions on the elastic properties of solid 4He; however, these calculations have treated zero point motions using either the Einstein or Debye approximations, which are insufficient in the molar volume range where solid 4He is characterized as a quantum solid. Our VPI calculations allow for a more accurate treatment of the zero point motions which include atomic correlation. From these calculations, we find that agreement with the experimental bulk modulus is significantly improved when three-body interactions are considered. In addition, three-body interactions result in non-negligible differences in the calculated pure shear constants and nonzero elastic constants, particularly at higher densities, where differences of up to 26.5% are observed when three-body interactions are included. We compare to the available experimental data and find that our results are generally in as good or better agreement with experiment as previous theoretical investigations.
Multi-phase ionization dynamics of carbon thin film irradiated by high power short pulse laser
Authors: Kawahito Daiki , Kishimoto Yasuaki
Published: September 2017

The ionization dynamics of a carbon thin film irradiated by a high power short pulse laser in the range of 1019−20 W/cm2 are studied using the extended particle-based integrated code (EPIC), which includes atomic and collisional processes. Two types of ionization dynamics exhibiting different spatio-temporal structures are found to predominantly regulate the process, and arise depending on the laser amplitude. The first is a fast convective propagation for charge states up to C4+, which keeps a steep ionization front. The velocity of the front is of the order of the speed of light. The front formation results from the localized longitudinal electrostatic field and associated field ionization, which in turn propagates inside the film. This convective propagation is triggered when the laser field becomes high enough that electron bunches accelerated by the laser ponderomotive force reach relativistic energies and penetrate inside the film across the surface. The second dynamics is a fast non-diffusive propagation of ionization showing a long plasma density scale length for C5+ and C6+. This process results predominantly from electron impact ionization by high energy electron bunches successively produced by the laser. These electron bunches also excite wake fields that propagate inside the film and contribute to ionizing the film to higher charge states, i.e., C5+ and C6+, especially near the front surface. The effect of field ionization loss, which sensitively influences the ionization dynamics in the relatively low laser power regime, is also discussed.
Slip avalanche in nanoscratching of metallic glasses
Authors: Han D. X. , Wang G. , Ren J. L. , Song S. X. , Li J. , Yi J. , Jia Y. D. , Xu H. , Chan K. C. , Liaw P. K.
Published: September 2017

Slip avalanches, similar to discrete earthquake events, of Zr-, Co-, and Ce-based metallic glasses during nanoscratching were investigated. Differing from the conventional continuum approach, mean-field theory, which is an inherently-discrete model, was applied to analytically compute intermittent slip avalanches. Mean-field theory was first connected with the potential energy barrier and concentration of free volume in order to study the stick-slip behavior. The results suggest that the motion behavior of free volume affects the critical slip avalanche size.
Continuous wave laser for tailoring the photoluminescence of silicon nanoparticles produced by laser ablation in liquid
Authors: Popovic Dusan M. , Kushima Akihiro , Bogdanovic Milena I. , Chai Jong Seo , Kasalica Becko , Trtica Milan , Stasic Jelena , Zekic Andrijana A.
Published: September 2017

Silicon nanoparticles (SiNPs) are attracting attention for applications in various fields, from energy storage to bio-imaging. One of their main advantages is good photoluminescence (PL) properties combined with the relatively high bio-compatibility. Here, we fabricated SiNPs by the laser ablation of silicon single crystal in de-ionized water, employing simultaneously the picosecond pulse laser (150 ps, 1064 nm, 7 mJ/pulse) and a continuous wave (CW) laser (532 nm, 270 mW). TEM analysis (bright field TEM, HRTEM, HAADF, EDS) clearly shows that the introduction of the CW laser significantly increases the crystallinity of the produced nanoparticles, which may be crucial for many optical and electronic applications. The obtained SiNPs exhibit good blue photoluminescence properties, and the introduction of the CW laser into the fabrication process leads to the considerable increases in the photoluminescence. Additionally, we conducted a detailed analysis on the aging-time dependence and the excitation wavelength-dependent PL. The results indicate that the blue photoluminescence may be ascribed to quantum confinement effect, interface related states, and defect in the O-containing layer (shell) of the nanoparticles. We demonstrate that the relative share of these mechanisms in overall PL is significantly affected by the introduction of the CW laser to the pulse laser ablation and it may improve the applicability of the Si nanoparticles produced to a wide variety of fields.
Transition of vertically aligned liquid crystal driven by fan-shaped electric field
Authors: Tsung J. W. , Ting T. L. , Chen C. Y. , Liang W. L. , Lai C. W. , Lin T. H. , Hsu W. H.
Published: September 2017

Interdigital electrodes are implemented in many commercial and novel liquid crystal devices to align molecules. Although many empirical principles and patents apply to electrode design, only a few numerical simulations of alignment have been conducted. Why and how the molecules align in an ordered manner has never been adequately explained. Hence, this investigation addresses the Fréedericksz transition of vertically aligned liquid crystal that is driven by fishbone electrodes, and thereafter identifies the mechanism of liquid crystal alignment. Theoretical calculations suggest that the periodic deformation that is caused by the fan-shaped fringe field minimizes the free energy in the liquid crystal cell, and the optimal alignment can be obtained when the cell parameters satisfy the relation p/2d=k11/k33, where p is the spatial period of the strips of the electrode; d denotes the cell gap; and k11 and k33 are the splay and bend elastic constants of the liquid crystal, respectively. Polymer-stabilized vertical alignment test cells with various p values and spacings between the electrodes were fabricated, and the process of liquid crystal alignment was observed under an optical microscope. The degree of alignment was evaluated by measuring the transmittance of the test cell. The experimental results were consistent with the theoretical predictions. The principle of design, p/2d=k11/k33, greatly improves the uniformity and stability of the aligned liquid crystal. The methods that are presented here can be further applied to cholesteric liquid crystal and other self-assembled soft materials.
Color atomic force microscopy: A method to acquire three independent potential parameters to generate a color image
Authors: Allain P. E. , Damiron D. , Miyazaki Y. , Kaminishi K. , Pop F. V. , Kobayashi D. , Sasaki N. , Kawakatsu H.
Published: September 2017

Atomic force microscopy has enabled imaging at the sub-molecular level, and 3D mapping of the tip-surface potential field. However, fast identification of the surface still remains a challenging topic for the microscope to enjoy widespread use as a tool with chemical contrast. In this paper, as a step towards implementation of such function, we introduce a control scheme and mathematical treatment of the acquired data that enable retrieval of essential information characterizing this potential field, leading to fast acquisition of images with chemical contrast. The control scheme is based on the tip sample distance modulation at an angular frequency ω, and null-control of the ω component of the measured self-excitation frequency of the oscillator. It is demonstrated that this control is robust, and that effective Morse Parameters that give satisfactory curve fit to the measured frequency shift can be calculated at rates comparable to the scan. Atomic features with similar topography were distinguished by differences in these parameters. The decay length parameter was resolved with a resolution of 10 pm. The method was demonstrated on quenched silicon at a scan rate comparable to conventional imaging.
Model of vertical plasma motion during the current quench
Authors: Kiramov D. I. , Breizman B. N.
Published: September 2017

Tokamak disruptions impair plasma position control, which allows the plasma column to move and hit the wall. These detrimental events enhance thermal and mechanical loads due to halo currents and runaway electron losses. Their fundamental understanding and prevention is one of the high-priority items for ITER.
Novel target design for enhanced laser driven proton acceleration
Authors: Dalui Malay , Kundu M. , Tata Sheroy , Lad Amit D. , Jha J. , Ray Krishanu , Krishnamurthy M.
Published: September 2017

We demonstrate a simple method of preparing structured target for enhanced laser-driven proton acceleration under target-normal-sheath-acceleration scheme. A few layers of genetically modified, clinically grown micron sized E. Coli bacteria cell coated on a thin metal foil has resulted in an increase in the maximum proton energy by about 1.5 times and the total proton yield is enhanced by approximately 25 times compared to an unstructured reference foil at a laser intensity of 1019 W/cm2. Particle-in-cell simulations on the system shows that the structures on the target-foil facilitates anharmonic resonance, contributing to enhanced hot electron production which leads to stronger accelerating field. The effect is observed to grow as the number of structures is increased in the focal area of the laser pulse.
Tunable bandgap in halogen doped 2D nitrogenated microporous materials
Authors: Pimachev Artem , Proshchenko Vitaly , Dahnovsky Yuri
Published: September 2017

The quest for new materials with extraordinary electronic, magnetic, and optical properties leads to the synthesis of 2D nitrogenated microporous materials with the hole diameter of 1.16 nm. We computationally study the evolution of the energy bandgaps, optical, and transport properties with the following substituents: hydrogen, fluorine, chlorine, and iodine. We find that such a small perturbation by these atoms has a tremendous impact on the electronic properties of these materials. Indeed, the direct energy bandgaps can be tuned from 1.64 to 0.96 eV by the substituents from hydrogen to iodine. The optical gaps demonstrate similar dependence. From the transport properties, we calculate the effective masses of π-conjugated microporous polymers and find that the conduction electron effective masses are insensitive to halogen substituents while for some low-lying energy valence bands the effective masses can be drastically increased from 0.71 to 2.98 me and 0.28 to 0.58 me for the heavy and light holes, respectively. The application of the nitrogenated microporous materials is very broad. They can be useful as sensitizers in solar cells, for water splitting catalysis, in biomedicine, and for gas and energy storage.
Evaluating the correlation between liquid fragility and glass-forming ability in the extremely strong Ce-based bulk metallic glasses
Authors: Zhao Y. , Zhang B.
Published: September 2017

This investigation focuses on liquid fragility (m) and its correlation with glass-forming ability (GFA) of Ce-Ga-Cu, Ce-Al-Cu-Ni and newly developed Ce-Ga-Cu-Ni bulk metallic glass (BMG) systems. The present Ce-based BMGs belong to the extremely strong glass-forming system, whose fragility m values lie in a strong liquid range of 18–33. The quantitative correlation between m and GFA in the present Ce-based BMGs cannot be described well by previous criteria proposed by Senkov [Phys. Rev. B 76, 104202 (2007)], Wang [Appl. Phys. Lett. 100, 261913 (2012)], and Johnson [Nat. Commun. 7, 10313 (2016)]. By considering both the stability of the liquid phase and the stability of the competing crystalline phases, it is found that the stability of the competing crystalline phases plays a dominant role in the determination of GFA of strong Ce-based BMGs. And, the influence of reduced glass transition temperature (Trg) on GFA would be submerged by that of fragility m when m is below ∼30. The results help in further understanding the underlying correlation between fragility and GFA in metallic glasses, especially for the strong glass-forming liquids.
Spin polarization and magnetic characteristics at C6H6/Co2MnSi(001) spinterface
Authors: Sun Meifang , Wang Xiaocha , Mi Wenbo
Published: September 2017

Organic materials with mechanical flexibility, low cost, chemical engineering, and long spin lifetime attract considerable attention for building spintronic devices. Here, a C6H6/Co2MnSi(001) spinterface is investigated by first-principles calculations and spin-polarized scanning tunneling microscopy simulations. Several high symmetry adsorption sites are discussed, together with two possible surface terminations of Co2MnSi(001). An inversion of the spin polarization is induced near EF even in the case of an external electric field, indicating that C6H6 can act as a spin filter to exploit the spin injection efficiency in organic spintronic devices. Unlike previous studies on molecule/ferromagnet interfaces, this inversion is closely related to the electronic structure of the atoms in the subsurface layer of Co2MnSi according to the orbital symmetry analysis. Furthermore, the magnetic moment and magnetic anisotropic energy (MAE) in the outermost Co2MnSi layer are studied. Particularly, in the most stable configuration, the sign of MAE is inversed due to hybridization between C p and Co dz2 orbitals, which suggests that a greater modification on MAE can be achieved by the use of a highly chemically reactive organic molecule. These findings improve the study on the engineering of magnetic properties at molecule/ferromagnetic interfaces through a single π-conjugated organic molecule.
Hybrid 2D patterning using UV laser direct writing and aerosol jet printing of UV curable polydimethylsiloxane
Authors: Obata Kotaro , Schonewille Adam , Slobin Shayna , Hohnholz Arndt , Unger Claudia , Koch Jürgen , Suttmann Oliver , Overmeyer Ludger
Published: September 2017

The hybrid technique of aerosol jet printing and ultraviolet (UV) laser direct writing was developed for 2D patterning of thin film UV curable polydimethylsiloxane (PDMS). A dual atomizer module in an aerosol jet printing system generated aerosol jet streams from material components of the UV curable PDMS individually and enables the mixing in a controlled ratio. Precise control of the aerosol jet printing achieved the layer thickness of UV curable PDMS as thin as 1.6 μm. This aerosol jet printing system is advantageous because of its ability to print uniform thin-film coatings of UV curable PDMS on planar surfaces as well as free-form surfaces without the use of solvents. In addition, the hybrid 2D patterning using the combination of UV laser direct writing and aerosol jet printing achieved selective photo-initiated polymerization of the UV curable PDMS layer with an X-Y resolution of 17.5 μm.
Temperature dependence of the band gap of zinc nitride observed in photoluminescence measurements
Authors: Trapalis A. , Farrer I. , Kennedy K. , Kean A. , Sharman J. , Heffernan J.
Published: September 2017

We report the photoluminescence properties of DC sputtered zinc nitride thin films in the temperature range of 3.7–300 K. Zinc nitride samples grown at 150 °C exhibited a narrow photoluminescence band at 1.38 eV and a broad band at 0.90 eV, which were attributed to the recombination of free carriers with a bound state and deep-level defect states, respectively. The high-energy band followed the Varshni equation with temperature and became saturated at high excitation powers. These results indicate that the high-energy band originates from shallow defect states in a narrow bandgap. Furthermore, a red-shift of the observed features with increasing excitation power suggested the presence of inhomogeneities within the samples.
An ab initio study of the electronic structure of indium and gallium chalcogenide bilayers
Authors: Ayadi T. , Debbichi L. , Said M. , Lebègue S.
Published: September 2017

Using first principle calculations, we have studied the structural and electronic properties of two dimensional bilayers of indium and gallium chalcogenides. With density functional theory corrected for van der Waals interactions, the different modes of stacking were investigated in a systematic way, and several of them were found to compete in energy. Then, their band structures were obtained with the GW approximation and found to correspond to indirect bandgap semiconductors with a small dependency on the mode of stacking. Finally, by analysing the electron density, it appeared that GaSe–InS is a promising system for electron-hole separation.
Magnetization, ESR, and giant magnetocaloric effects in nanocrystals of Haldane-chain compound Gd2BaNiO5
Authors: Ruan M. Y. , Ouyang Z. W. , Wang Z. X. , Xia Z. C. , Rao G. H.
Published: September 2017

The magnetization and electron spin resonance (ESR) in nanocrystals of Haldane-chain antiferromagnet Gd2BaNiO5 have been investigated. It is revealed that a reduction in crystal size results in an enhancement of magnetization due to a large number of paramagnetic Gd3+ and Ni2+ ions forming on the surfaces of nanocrystals. The smallest nanoparticles with an average size of 45 nm behave like a paramagnet, as evidenced by our ESR data. Upon application of an external magnetic field, the weakly coupled spins can be well aligned along the direction of the magnetic field, giving rise to a giant entropy change of −ΔSm = 36 J⋅kg−1⋅K−1 at 2 K in a field range of 0–7 T. This value is larger than those of most rare-earth-based compounds reported. The large value of −ΔSm, together with the absence of thermal and field hysteresis, makes Gd2BaNiO5 nanocrystals very promising candidates for low-temperature magnetic refrigeration.
A qualitative quantum rate model for hydrogen transfer in soybean lipoxygenase
Authors: Jevtic S. , Anders J.
Published: September 2017

The hydrogen transfer reaction catalysed by soybean lipoxygenase (SLO) has been the focus of intense study following observations of a high kinetic isotope effect (KIE). Today high KIEs are generally thought to indicate departure from classical rate theory and are seen as a strong signature of tunnelling of the transferring particle, hydrogen or one of its isotopes, through the reaction energy barrier. In this paper, we build a qualitative quantum rate model with few free parameters that describes the dynamics of the transferring particle when it is exposed to energetic potentials exerted by the donor and the acceptor. The enzyme’s impact on the dynamics is modelled by an additional energetic term, an oscillatory contribution known as “gating.” By varying two key parameters, the gating frequency and the mean donor-acceptor separation, the model is able to reproduce well the KIE data for SLO wild-type and a variety of SLO mutants over the experimentally accessible temperature range. While SLO-specific constants have been considered here, it is possible to adapt these for other enzymes.
The kinetic energy operator for distance-dependent effective nuclear masses: Derivation for a triatomic molecule
Authors: Khoma Mykhaylo , Jaquet Ralph
Published: September 2017

The kinetic energy operator for triatomic molecules with coordinate or distance-dependent nuclear masses has been derived. By combination of the chain rule method and the analysis of infinitesimal variations of molecular coordinates, a simple and general technique for the construction of the kinetic energy operator has been proposed. The asymptotic properties of the Hamiltonian have been investigated with respect to the ratio of the electron and proton mass. We have demonstrated that an ad hoc introduction of distance (and direction) dependent nuclear masses in Cartesian coordinates preserves the total rotational invariance of the problem. With the help of Wigner rotation functions, an effective Hamiltonian for nuclear motion can be derived. In the derivation, we have focused on the effective trinuclear Hamiltonian. All necessary matrix elements are given in closed analytical form. Preliminary results for the influence of non-adiabaticity on vibrational band origins are presented for H3+.
Pulsed laser deposition of piezoelectric lead zirconate titanate thin films maintaining a post-CMOS compatible thermal budget
Authors: Schatz A. , Pantel D. , Hanemann T.
Published: September 2017

Integration of lead zirconate titanate (Pb[Zrx,Ti1-x]O3 – PZT) thin films on complementary metal-oxide semiconductor substrates (CMOS) is difficult due to the usually high crystallization temperature of the piezoelectric perovskite PZT phase, which harms the CMOS circuits. In this work, a wafer-scale pulsed laser deposition tool was used to grow 1 μm thick PZT thin films on 150 mm diameter silicon wafers. Three different routes towards a post-CMOS compatible deposition process were investigated, maintaining a post-CMOS compatible thermal budget limit of 445 °C for 1 h (or 420 °C for 6 h). By crystallizing the perovskite LaNiO3 seed layer at 445 °C, the PZT deposition temperature can be lowered to below 400 °C, yielding a transverse piezoelectric coefficient e31,f of −9.3 C/m2. With the same procedure, applying a slightly higher PZT deposition temperature of 420 °C, an e31,f of −10.3 C/m2 can be reached. The low leakage current density of below 3 × 10−6 A/cm2 at 200 kV/cm allows for application of the post-CMOS compatible PZT thin films in low power micro-electro-mechanical-systems actuators.
Optimizing GaInN/GaN light-emitting diode structures under piezoelectric polarization
Authors: Elsaesser David R. , Durniak Mark T. , Bross Adam S. , Wetzel Christian
Published: September 2017

We model and optimize various light emitting diode structures under bias voltage to maximize emission efficiency with particular respect to piezoelectric polarization. We compare polar and non-polar structures, namely, wurtzite c-plane, a-plane, (11–22) semi-polar, and (001) cubic crystal orientations in self-consistent Schrödinger-Poisson and drift-diffusion models. We consider both structures strained to a GaN pn-junction and strain-reduced systems based on GaInN templates. In light of numerous experimental findings of the actual electric field strength, we find it necessary to reduce the piezoelectric coefficients over those commonly cited. A weaker variation with composition or wavelength is the consequence. For the non-polar and cubic systems, we find a 22% increase of the electron-hole overlap and an 18% increase for the c-plane strain-reduced system at an InN fraction of x = 0.30 when compared to standard c-plane structures. For the green and longer wavelength range, we find that strain-reduced and cubic GaN systems should hold particular promise for higher radiative efficiency.
3D PIC-MCC simulations of positive streamers in air gaps
Authors: Jiang M. , Li Y. , Wang H. , Liu C.
Published: September 2017

Simulation of positive streamer evolution is important for understanding the microscopic physical process in discharges. Simulations described in this paper are done using a 3D Particle-In-Cell, Monte-Carlo-Collision code with photoionization. Three phases of a positive streamer evolution, identified as initiation, propagation, and branching are studied during simulations. A homogeneous electric field is applied between parallel-flat electrodes forming a millimeter air gap to make simulations and analysis more simple and general. Free electrons created by the photoionization process determine initiation, propagation, and branching of the streamers. Electron avalanches form a positive streamer tip, when the space charge of ions at the positive tip dominates the local electric field. The propagation of the positive tip toward a cathode is the result of combinations of the positive tip and secondary avalanches ahead of it. A curved feather-like channel is formed without obvious branches when the electric field between electrodes is 50 kV/cm. However, a channel is formed with obvious branches when the electric field increases up to 60 kV/cm. In contrast to the branches around a sharp needle electrode, branches near the flat anode are formed at a certain distance away from it. Simulated parameters of the streamer such as diameter, maximum electric field, propagation velocity, and electron density at the streamer tip are in a good agreement with those published earlier.
Homodyne phase sensitive terahertz spectrometer
Authors: Rumyantsev S. , Liu X. , Kachorovskii V. , Shur M.
Published: September 2017

We present the theory of a field effect transistor (FET) operating as a THz or far infrared detector. We demonstrate that the detected signal is enhanced by orders of magnitudes by using a homodyne detection scheme involving the interference of a weak incoming signal and a strong signal of a local oscillator with the close frequency. We developed a theory valid for the arbitrary relationship between the amplitude of the local oscillator and the gate voltage swing. Remarkably, the response saturates at a high local oscillator intensity at the value which depends on the phase difference between the signals. The observed gain in this regime is over 100, and the predicted maximum gain in this operating regime is on the order of 105. These results show that a FET could be used as a sensitive spectrometer and/or interferometer when exposed to a strong tunable local oscillator signal with the varying frequencies and phases. This regime of the detector operation is very promising for the interferometric and spectroscopic applications in the subterahertz and terahertz ranges.
An enhanced theory for nonlinear and irreversible thermodynamics
Authors: Blaustein Rich
Published: September 2017

Two theorists build upon seminal irreversible thermodynamic theory and add the effects of microscopic fluctuations and stochasticity.
Seasonal hogget grazing as a potential alternative grazing system for the Qinghai-Tibetan plateau: weight gain and animal behaviour under continuous or rotational grazing at high or low stocking rates
Authors: Du W. C. , Yan T. , Chang S. H. , Wang Z. F. , Hou F. J.
Published: September 2017

The traditional transhumance grazing system on the Qinghai-Tibetan Plateau (QTP) is being replaced by a system in which pastoralists are allocated fixed areas for grazing. In this context, we conducted experiments to evaluate a possible change to seasonal grazing of young animals for weight gain, and the effects of grazing management (continuous grazing (CG) vs rotational grazing (RG)) and stocking rate (SR) on the performance and behaviour of Oura-type Tibetan sheep. In Experiment 1 (June–December 2014), 72 Tibetan sheep (initial bodyweight (BW) 32.2 ± 3.37 kg) were allocated to one of three treatments: (1) CG24 – eight sheep grazed continuously in a single 2-ha plot for the entire duration of the experiment; (2) RG24 – eight sheep grazed in a 1-ha plot from June to September (growing season), and then moved to a new plot for September–December grazing (early cold season); (3) RG48 – eight sheep grazed in a 0.5-ha plot, but otherwise as for RG24. All treatments had three replicates. In Experiment 2 (September–December 2014), 48 Tibetan sheep (initial BW 46.3 ± 1.62 kg) were used to repeat the RG24 and RG48 treatments imposed in the early cold season of the Experiment 1. In both experiments, increasing SR significantly reduced bodyweight gain (BWG) per head and increased BWG per ha in the RG treatments. In Experiment 1, RG, compared with CG, did not significantly affect BWG per head, BWG per ha, or feed utilisation efficiency. In both experiments weight gain was small or negative in the early cold season. These results indicate that removal of sheep at the onset of the cold season will be important for retention of the weight gain achieved in the growing season but choice between a CG and RG grazing system is unimportant for the production efficiency in the proposed grazing system of Tibetan sheep.
Performance of improved sweetpotato (Ipomoea batatas L.) cultivars under different soil types of Samoa
Authors: Siose Taniela K. , Guinto Danilo F.
Published: September 2017

There is need to diversify crop production in Samoa which currently depends mainly on taro crop, that has proved to be susceptible to fungus and other diseases, to as safeguard against risks of crop failures and adapt to climatic changes. The potential of introducing sweetpotato as a second staple food in Samoa is explored in this study. The study analyses the suitability of sweetpotato cultivars in Samoan agro-environment and major soil types. For this purpose a twenty week pot experiment was conducted to investigate the performance of three improved sweetpotato cultivars (IB/PR/12, IB/PR/13 and IB/PH/03) on four different types of soils in Samoa (Savaia calcareous sandy loam, Matafa’a red acidic, Faleula silty clay and Saleimoa silty clay) in a factorial arrangement of treatments in randomised complete block design with three replications. Results revealed that soil type had a significant effect on vine growth, and storage root yield with the best yield obtained in the silty clay soils having high K content. Retarded plant growth observed under the acidic soil having low K content resulted in lowest storage root yield. A significant varietal difference was recorded in sweetpotato growth and yield. IB/PH/03 was inferior in vine length, but produced comparatively highest number of vines per plant, and storage root yield attesting its adaptability in all the four tested soil types of Samoa and has potentiality to be promoted for wider adoption. A follow-up field study is needed to verify our preliminary results under pot culture on different soil types of Samoa.
Disconnecting structure and dynamics in glassy thin films
Authors: Sussman Daniel M. , Schoenholz Samuel S. , Cubuk Ekin D. , Liu Andrea J.
Published: September 2017

Significance

Do glassy dynamics depend strongly on local structure? In bulk systems, a quantitative answer to this question exists and is affirmative. The dynamical behavior of nanometrically thin glassy films is strikingly different from bulk systems, and it is natural to ask whether this difference stems from local structural differences. Using machine learning techniques, we show that altered dynamics near an interface do not stem from changes of local structure near the interface. Rather, the dynamics depend on the simultaneous occurrence of two independent processes, one that depends on structure but not position within the film, and an Arrhenius process that does not depend on structure but depends sensitively on position.
Structure insight of GSDMD reveals the basis of GSDMD autoinhibition in cell pyroptosis
Authors: Kuang Siyun , Zheng Jun , Yang Hui , Li Suhua , Duan Shuyan , Shen Yanfang , Ji Chaoneng , Gan Jianhua , Xu Xue-Wei , Li Jixi
Published: September 2017

Significance

The protein gasdermin D (GSDMD) is the physiological substrate of inflammatory caspases and plays key roles in cell pyroptosis upon microbial infection and associated danger signals. GSDMD, as well as other gasdermin members, can bind lipid and form pore structures to induce pyroptosis. However, detailed structural information for GSDMD remains unknown. We have determined the crystal structure of the C-terminal domain of human GSDMD. The structure reveals that the first loop inserts into the N-terminal domain to help stabilize the full-length GSDMD conformation. Furthermore, we identify that one short segment is sufficient to kill bacteria and can act as a potential antimicrobial peptide. Thus, these findings offer a perspective for understanding the mechanism of GSDMD in innate immune defense.
Topological semimetal in honeycomb lattice LnSI
Authors: Nie Simin , Xu Gang , Prinz Fritz B. , Zhang Shou-cheng
Published: September 2017

Significance

We show that fruitful topological states can be realized in a special honeycomb lattice model. Guided by this model, we find that GdSI, the long perceived ideal Weyl semimetal, has only two pairs of Weyl nodes and that LuSI (YSI) is a topological insulator with the right-handed helical surface states. Our work provides a mechanism to study topological semimetals and proposes a platform for exploring the physics of Weyl semimetals as well as related device designs.