bluuebunny/crossref_metadata_2025 huggingface dataset:
Robust performance design of a state predictive controller on parameter space
Authors: Saeki Masami , Assi Mouhammad , Wada Nobutaka
Published: December 2013

Robust performance against a multiplicative uncertainty is an important measure for closed‐loop performance. In this article, a parameter space design method of a state predictive controller is proposed for second‐order time‐delay systems. The boundaries of two permissible regions of state feedback gains and observer gains that satisfy the robust performance condition at each frequency are obtained. An appropriate solution can be found after a few iterations by drawing the regions on the two parameter planes, alternatively. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Ingestion of fat tissue from wolf prey species and its influence on fatty‐acid composition in sled dogs
Authors: Berkley Elizabeth A. , Peckham Scott D. , Sampath Harini , Bodewes Joseph , Ntambi James M. , Van Deelen Timothy R.
Published: December 2013

We conducted feeding experiments on Canadian Inuit sled dogs (Canis familiaris borealis) as a surrogate for wolves (Canis lupus) to examine whether fatty‐acid signatures could be used to estimate relative intake of common prey in the Great Lakes area, USA. We obtained fat tissue from white‐tailed deer (Odocoileus virginianus), moose (Alces alces), beaver (Castor canadensis), and domestic cow (Bos spp.), and provided 8 treatments of prescribed proportions to 6–7 dogs/treatment (total 50 dogs) over a period of 60 days. Pre and post‐treatment fat‐tissue samples from dogs were collected by biopsy to examine fatty‐acid composition. Approximately 10 60‐mg samples of fat from each prey species were analyzed using gas chromatography to develop a database of fatty‐acid signatures for each prey species. Fatty‐acid signatures of these 4 prey species were distinct. Fatty‐acid signatures of sled dogs changed with diet consistent with prescribed treatments. However, we could not reliably reconstruct their actual diet using Iverson et al.'s (2004) model. This study demonstrates that analysis of both prey and predator's fatty‐acid composition may be an innovative method to estimate dietary history of a terrestrial predator, such as wolves, but additional work is needed to make dietary predictions. © 2013 The Wildlife Society
Perceived Risk Following Melanoma Genetic Testing: A 2‐Year Prospective Study Distinguishing Subjective Estimates from Recall
Authors: Aspinwall Lisa G. , Taber Jennifer M. , Kohlmann Wendy , Leaf Samantha L. , Leachman Sancy A.
Published: December 2013

A major goal of predictive genetic testing is to alert people to their risk before illness onset; however, little is known about how risk perceptions change following genetic testing and whether information is recalled accurately over time. In the United States, a CDKN2A/p16 mutation confers 76 % lifetime risk of melanoma. Following genetic counseling and test reporting, subjective risk estimates and recall of counselor‐provided risk estimates were assessed 5 times over the next 2 years among 60 adult members of 2 extended CDKN2A/p16 kindreds. No sustained changes from baseline in risk perceptions were reported. Unaffected carriers (n = 15) consistently reported significantly lower subjective risk estimates (46 %) than they were actually given (76 %, p < 0.001) or recalled having been given (60 %, p < 0.001). Noncarriers’ (n = 27) risk estimates decreased following results disclosure, but rebounded, with both subjective and recalled estimates subsequently exceeding what they were told by the counselor (both ps < 0.001). Affected carriers’ (n = 18) risk estimates for developing a new melanoma corresponded well to counselor‐provided information (p = 0.362). For all 3 patient groups, results were consistent across multiple risk measures and remained similar when demographic, phenotypic, and baseline behavioral contributors to melanoma risk were statistically controlled. These findings are consistent with other studies of risk perception, but additional studies of more diverse populations are needed to understand the reasons behind both the persistence of initial risk estimates and their divergence from information provided by the counselor during genetic counseling. Additionally, determining whether holding subjective risk perceptions that differ from counselor‐provided information ultimately affects adherence to management recommendations will help guide the presentation of risk information in genetic counseling practice.
Peroxynitrite chemistry derived from nitric oxide reaction with a Cu(ii)–OOH species and a copper mediated NO reductive coupling reaction
Authors: Kim Sunghee , Siegler Maxime A. , Karlin Kenneth D.
Published: December 2013

New peroxynitrite–copper chemistry ensuesviaaddition of ˙NO(g)to a CuII–hydroperoxo species; the ligand–Cu(i) complex was shown to effect ˙NO(g)reductive coupling.
Activation of gaseous PH3 with low coordinate diaryltetrylene compounds
Authors: Dube Jonathan W. , Brown Zachary D. , Caputo Christine A. , Power Philip P. , Ragogna Paul J.
Published: December 2013

Two modes of reactivity are observed when pyrophoric phosphine gas reacts with diaryltetrylenes, representing unique main-group P–H bond activation.
Surface-assisted cis–trans isomerization of an alkene molecule on Cu(110)
Authors: Sun Qiang , Zhang Chi , Wang Likun , Li Zhiwen , Hu Aiguo , Tan Qinggang , Xu Wei
Published: December 2013

Interplay of STM imaging and DFT calculations demonstrates the isomerization of an alkene molecule on Cu(110) under ultrahigh vacuum conditions. We show that the on-surfacecis–transisomerization could efficiently occur well below room temperature, in which the surface is speculated to play a key role in assisting this isomerization process.
A series of metal–organic frameworks containing diverse secondary building units derived from a flexible triazine-based tetracarboxylic ligand
Authors: Li Jie , Sheng Tianlu , Bai Songyan , Hu Shengmin , Wen Yuehong , Fu Ruibiao , Huang Yihui , Xue Zhenzhen , Wu Xintao
Published: December 2013

Five new coordination polymers containing diverse SBUs derived from a flexible triazine-based tetracarboxylic acid have been solvothermally synthesized and characterized.
High performance Pd nanocrystals supported on SnO2-decorated graphene for aromatic nitro compound reduction
Authors: Li Hongyan , Gan Shiyu , Han Dongxue , Ma Weiguang , Cai Bin , Zhang Wei , Zhang Qixian , Niu Li
Published: December 2013

We reported a hybrid material of ultrafine Pd nanocrystals grown on an excellent support of SnO2-decorated graphene nanosheets for the highly efficient reduction of a representative aromatic nitro compound.
A star-shaped bipolar host material based on carbazole and dimesitylboron moieties for fabrication of highly efficient red, green and blue electrophosphorescent devices
Authors: Shi Heping , Xin Dehua , Dong Xiuqing , Dai Jian-xin , Wu Xiaohuan , Miao Yanqin , Fang Li , Wang Hua , Choi Martin M. F.
Published: December 2013

PhOLEDs fabricated from a new bipolar host material with high triplet energy exhibit reasonably good performances.
Dynamics of Gαq-protein–p63RhoGEF interaction and its regulation by RGS2
Authors: Bodmann Eva-Lisa , Rinne Andreas , Brandt Dominique , Lutz Susanne , Wieland Thomas , Grosse Robert , Bünemann Moritz
Published: December 2013

Some G-protein-coupled receptors regulate biological processes via Gα12/13- or Gαq/11-mediated stimulation of RhoGEFs (guanine-nucleotide-exchange factors). p63RhoGEF is known to be specifically activated by Gαq/11 and mediates a major part of the acute response of vascular smooth muscle cells to angiotensin II treatment. In order to gain information about the dynamics of receptor-mediated activation of p63RhoGEF, we developed a FRET-based assay to study interactions between Gαq–CFP and Venus–p63RhoGEF in single living cells. Upon activation of histaminergic H1 or muscarinic M3 receptors, a robust FRET signal occurred that allowed for the first time the analysis of the kinetics of this interaction in detail. On- and off-set kinetics of Gαq–p63RhoGEF interactions closely resembled the kinetics of Gαq activity. Analysis of the effect of RGS2 (regulator of G-protein signalling 2) on the dynamics of Gαq activity and their interaction with p63RhoGEF showed that RGS2 is able to accelerate both deactivation of Gαq proteins and dissociation of Gαq and p63RhoGEF to a similar extent. Furthermore, we were able to detect activation-dependent FRET between RGS2 and p63RhoGEF and observed a reduced p63RhoGEF-mediated downstream signalling in the presence of RGS2. In summary, these observations support the concept of a functional activation-dependent p63RhoGEF–Gαq–RGS2 complex.
A structure-guided fragment-based approach for the discovery of allosteric inhibitors targeting the lipophilic binding site of transcription factor EthR
Authors: Surade Sachin , Ty Nancy , Hengrung Narin , Lechartier Benoit , Cole Stewart T. , Abell Chris , Blundell Tom L.
Published: December 2013

A structure-guided fragment-based approach was used to target the lipophilic allosteric binding site of Mycobacterium tuberculosis EthR. This elongated channel has many hydrophobic residues lining the binding site, with few opportunities for hydrogen bonding. We demonstrate that a fragment-based approach involving the inclusion of flexible fragments in the library leads to an efficient exploration of chemical space, that fragment binding can lead to an extension of the cavity, and that fragments are able to identify hydrogen-bonding opportunities in this hydrophobic environment that are not exploited in Nature. In the present paper, we report the identification of a 1 μM affinity ligand obtained by structure-guided fragment linking.
Analysis of an opportunistic large array line network with Bernoulli node deployment
Authors: Hassan Syed Ali , Ingram Mary Ann
Published: December 2013

A linear multi‐hop cooperative network is considered where the relay nodes are deployed in a random fashion according to a Bernoulli random process. The transmission from one hop to another is modelled as a discrete‐time Markov process while taking into account the random locations of the participating nodes along with the Rayleigh fading channel model. Quasi‐stationary theory of Markov chains has been applied to study the various properties of the network under consideration, including successful probability of hops as well as network coverage. It is shown that there is a loss of one‐hop success probability when the random deployment is done compared to a regular deployment. However, an additional signal‐to‐noise ratio margin has also been quantified for obtaining a desired quality of service and one‐hop success probability.
Switch‐filter wavelength selector: simulation and experiment
Authors: Stabile Ripalta , Calabretta Nicola , Williams Kevin A.
Published: December 2013

A lossless programmable wavelength selector using a chain of switched optical filter cells is studied. One of N wavelength channels can be selected with log2 N switching cells, allowing a sub‐linear scaling for electrode number with channel number. Each filter cell is based on the sequence of an amplifying Mach‐Zehnder interferometer and an optical switch. Fine wavelength tuning and digital wavelength selection are demonstrated in a loss‐compensating circuit, which allows the fast tuning of the filter pass‐bands to select channels. A model is implemented and experimentally verified against an integrated circuit implementation for the case of a 200 GHz grid selector to verify the operating characteristics and study scaling. Channel selection is modelled with two different methods: pass‐band selection and null‐rejection. The alignment of the filter nulls to reject unwanted wavelengths is observed to improve adjacent cross‐talk performance by 19 dB. This enhanced mode of operation allows a five‐stage selector for a 32‐channel, 100 GHz grid wavelength selector to perform with worst‐case cross‐talk below −25.7 dB with a control current tolerance of greater than 0.6 mA and an integrated cross‐talk of −21.3 dB at the optimal control current.
Ion source and injection line for high intensity medical cyclotron
Authors: Jia XianLu , Guan Fengping , Yao Hongjuan , Zhang TianJue , Yang Jianjun , Song Guofang , Ge Tao , Qin Jiuchang
Published: December 2013

A 14 MeV high intensity compact cyclotron, CYCIAE-14, was built at China Institute of Atomic Energy (CIAE). An injection system based on the external H− ion source was used on CYCIAE-14 so as to provide high intensity beam, while most positron emission tomography cyclotrons adopt internal ion source. A beam intensity of 100 μA/14 MeV was extracted from the cyclotron with a small multi-cusp H− ion source (CIAE-CH-I type) and a short injection line, which the H− ion source of 3 mA/25 keV H− beam with emittance of 0.3π mm mrad and the injection line of with only 1.2 m from the extraction of ion source to the medial plane of the cyclotron. To increase the extracted beam intensity of the cyclotron, a new ion source (CIAE-CH-II type) of 9.1 mA was used, with maximum of 500 μA was achieved from the cyclotron. The design and test results of the ion source and injection line optimized for high intensity acceleration will be given in this paper.
Improvement of uniformity of the negative ion beams by tent-shaped magnetic field in the JT-60 negative ion source
Authors: Yoshida Masafumi , Hanada Masaya , Kojima Atsushi , Kashiwagi Mieko , Grisham Larry R. , Akino Noboru , Endo Yasuei , Komata Masao , Mogaki Kazuhiko , Nemoto Shuji , Ohzeki Masahiro , Seki Norikazu , Sasaki Shunichi , Shimizu Tatsuo , Terunuma Yuto
Published: December 2013

Non-uniformity of the negative ion beams in the JT-60 negative ion source with the world-largest ion extraction area was improved by modifying the magnetic filter in the source from the plasma grid (PG) filter to a tent-shaped filter. The magnetic design via electron trajectory calculation showed that the tent-shaped filter was expected to suppress the localization of the primary electrons emitted from the filaments and created uniform plasma with positive ions and atoms of the parent particles for the negative ions. By modifying the magnetic filter to the tent-shaped filter, the uniformity defined as the deviation from the averaged beam intensity was reduced from 14% of the PG filter to ∼10% without a reduction of the negative ion production.
Equivalent circuit of radio frequency-plasma with the transformer model
Authors: Nishida K. , Mochizuki S. , Ohta M. , Yasumoto M. , Lettry J. , Mattei S. , Hatayama A.
Published: December 2013

LINAC4 H− source is radio frequency (RF) driven type source. In the RF system, it is required to match the load impedance, which includes H− source, to that of final amplifier. We model RF plasma inside the H− source as circuit elements using transformer model so that characteristics of the load impedance become calculable. It has been shown that the modeling based on the transformer model works well to predict the resistance and inductance of the plasma.
Molecular insight into conformational transmission of human P-glycoprotein
Authors: Chang Shan-Yan , Liu Fu-Feng , Dong Xiao-Yan , Sun Yan
Published: December 2013

P-glycoprotein (P-gp), a kind of ATP-binding cassette transporter, can export candidates through a channel at the two transmembrane domains (TMDs) across the cell membranes using the energy released from ATP hydrolysis at the two nucleotide-binding domains (NBDs). Considerable evidence has indicated that human P-gp undergoes large-scale conformational changes to export a wide variety of anti-cancer drugs out of the cancer cells. However, molecular mechanism of the conformational transmission of human P-gp from the NBDs to the TMDs is still unclear. Herein, targeted molecular dynamics simulations were performed to explore the atomic detail of the conformational transmission of human P-gp. It is confirmed that the conformational transition from the inward- to outward-facing is initiated by the movement of the NBDs. It is found that the two NBDs move both on the two directions (x and y). The movement on the x direction leads to the closure of the NBDs, while the movement on the y direction adjusts the conformations of the NBDs to form the correct ATP binding pockets. Six key segments (KSs) protruding from the TMDs to interact with the NBDs are identified. The relative movement of the KSs along the y axis driven by the NBDs can be transmitted through α-helices to the rest of the TMDs, rendering the TMDs to open towards periplasm in the outward-facing conformation. Twenty eight key residue pairs are identified to participate in the interaction network that contributes to the conformational transmission from the NBDs to the TMDs of human P-gp. In addition, 9 key residues in each NBD are also identified. The studies have thus provided clear insight into the conformational transmission from the NBDs to the TMDs in human P-gp.
Tensor decomposition in post-Hartree–Fock methods. II. CCD implementation
Authors: Benedikt Udo , Böhm Karl-Heinz , Auer Alexander A.
Published: December 2013

In a previous publication, we have discussed the usage of tensor decomposition in the canonical polyadic (CP) tensor format for electronic structure methods. There, we focused on two-electron integrals and second order Møller-Plesset perturbation theory (MP2). In this work, we discuss the CP format for Coupled Cluster (CC) theory and present a pilot implementation for the Coupled Cluster Doubles method. We discuss the iterative solution of the CC amplitude equations using tensors in CP representation and present a tensor contraction scheme that minimizes the effort necessary for the rank reductions during the iterations. Furthermore, several details concerning the reduction of complexity of the algorithm, convergence of the CC iterations, truncation errors, and the choice of threshold for chemical accuracy are discussed.
Approaching the complete-basis limit with a truncated many-body expansion
Authors: Richard Ryan M. , Lao Ka Un , Herbert John M.
Published: December 2013

High-accuracy electronic structure calculations with correlated wave functions demand the use of large basis sets and complete-basis extrapolation, but the accuracy of fragment-based quantum chemistry methods has most often been evaluated using double-ζ basis sets, with errors evaluated relative to a supersystem calculation using the same basis set. Here, we examine the convergence towards the basis-set limit of two- and three-body expansions of the energy, for water clusters and ion–water clusters, focusing on calculations at the level of second-order Møller-Plesset perturbation theory (MP2). Several different corrections for basis-set superposition error (BSSE), each consistent with a truncated many-body expansion, are examined as well. We present a careful analysis of how the interplay of errors (from all sources) influences the accuracy of the results. We conclude that fragment-based methods often benefit from error cancellation wherein BSSE offsets both incompleteness of the basis set as well as higher-order many-body effects that are neglected in a truncated many-body expansion. An n-body counterpoise correction facilitates smooth extrapolation to the MP2 basis-set limit, and at n = 3 affords accurate results while requiring calculations in subsystems no larger than trimers.
Existence of global weak solution for a reduced gravity two and a half layer model
Authors: Guo Zhenhua , Li Zilai , Yao Lei
Published: December 2013

We investigate the existence of global weak solution to a reduced gravity two and a half layer model in one-dimensional bounded spatial domain or periodic domain. Also, we show that any possible vacuum state has to vanish within finite time, then the weak solution becomes a unique strong one.
Approximate photochemical dynamics of azobenzene with reactive force fields
Authors: Li Yan , Hartke Bernd
Published: December 2013

We have fitted reactive force fields of the ReaxFF type to the ground and first excited electronic states of azobenzene, using global parameter optimization by genetic algorithms. Upon coupling with a simple energy-gap transition probability model, this setup allows for completely force-field-based simulations of photochemical cis→trans- and trans→cis-isomerizations of azobenzene, with qualitatively acceptable quantum yields. This paves the way towards large-scale dynamics simulations of molecular machines, including bond breaking and formation (via the reactive force field) as well as photochemical engines (presented in this work).
Direct current force sensing device based on compressive spring, permanent magnet, and coil-wound magnetostrictive/piezoelectric laminate
Authors: Leung Chung Ming , Or Siu Wing , Ho S. L.
Published: December 2013

A force sensing device capable of sensing dc (or static) compressive forces is developed based on a NAS106N stainless steel compressive spring, a sintered NdFeB permanent magnet, and a coil-wound Tb0.3Dy0.7Fe1.92/Pb(Zr, Ti)O3 magnetostrictive/piezoelectric laminate. The dc compressive force sensing in the device is evaluated theoretically and experimentally and is found to originate from a unique force-induced, position-dependent, current-driven dc magnetoelectric effect. The sensitivity of the device can be increased by increasing the spring constant of the compressive spring, the size of the permanent magnet, and/or the driving current for the coil-wound laminate. Devices of low-force (20 N) and high-force (200 N) types, showing high output voltages of 262 and 128 mV peak, respectively, are demonstrated at a low driving current of 100 mA peak by using different combinations of compressive spring and permanent magnet.
Cascaded spin motive force driven by the dynamics of the skyrmion lattice
Authors: Ohe Jun-ichiro , Shimada Yuhki
Published: December 2013

We numerically investigate the spin motive force (SMF) driven by the dynamics of a Skyrmion lattice. The rotating mode of the Skyrmion core excited by the AC magnetic field induces the large spin-dependent electric field near the core. Due to the collective dynamics of Skyrmion lattice, the measurable voltage is enhanced by the cascade effect of the SMF. The amplitude of the AC voltage is estimated to 30 μV in a macroscopic sample, where 100 Skyrmions exist between two probes. We also investigate the SMF due to the dynamics of the helical magnetic state, where the enhancement of the SMF does not occur.
Generalized Stoner-Wohlfarth model accurately describing the switching processes in pseudo-single ferromagnetic particles
Authors: Cimpoesu Dorin , Stoleriu Laurentiu , Stancu Alexandru
Published: December 2013

We propose a generalized Stoner-Wohlfarth (SW) type model to describe various experimentally observed angular dependencies of the switching field in non-single-domain magnetic particles. Because the nonuniform magnetic states are generally characterized by complicated spin configurations with no simple analytical description, we maintain the macrospin hypothesis and we phenomenologically include the effects of nonuniformities only in the anisotropy energy, preserving as much as possible the elegance of SW model, the concept of critical curve and its geometric interpretation. We compare the results obtained with our model with full micromagnetic simulations in order to evaluate the performance and limits of our approach.
Theoretical investigation of spin-filtering in CrAs/GaAs heterostructures
Authors: Stickler B. A. , Ertler C. , Pötz W. , Chioncel L.
Published: December 2013

The electronic structure of bulk zinc-blende GaAs, zinc-blende and tetragonal CrAs, and CrAs/GaAs supercells, computed within linear muffin-tin orbital (LMTO) local spin-density functional theory, is used to extract the band alignment for the [1,0,0] GaAs/CrAs interface in dependence of the spin orientation. With the lateral lattice constant fixed to the experimental bulk GaAs value, a local energy minimum is found for a tetragonal CrAs unit cell with a longitudinal ([1,0,0]) lattice constant reduced by ≈2%. Due to the identified spin-dependent band alignment, half-metallicity of CrAs no longer is a key requirement for spin-filtering. Based on these findings, we study the spin-dependent tunneling current in [1,0,0] GaAs/CrAs/GaAs heterostructures within the non-equilibrium Green's function approach for an effective tight-binding Hamiltonian derived from the LMTO electronic structure. Results indicate that these heterostructures are promising candidates for efficient room-temperature all-semiconductor spin-filtering devices.
First principles study of Fe in diamond: A diamond-based half metallic dilute magnetic semiconductor
Authors: Benecha E. M. , Lombardi E. B.
Published: December 2013

Half-metallic ferromagnetic ordering in semiconductors, essential in the emerging field of spintronics for injection and transport of highly spin polarised currents, has up to now been considered mainly in III–V and II–VI materials. However, low Curie temperatures have limited implementation in room temperature device applications. We report ab initio Density Functional Theory calculations on the properties of Fe in diamond, considering the effects of lattice site, charge state, and Fermi level position. We show that the lattice sites and induced magnetic moments of Fe in diamond depend strongly on the Fermi level position and type of diamond co-doping, with Fe being energetically most favorable at the substitutional site in p-type and intrinsic diamond, while it is most stable at a divacancy site in n-type diamond. Fe induces spin polarized bands in the band gap, with strong hybridization between Fe-3d and C-2s,2p bands. We further consider Fe-Fe spin interactions in diamond and show that substitutional Fe+1 in p-type diamond exhibits a half-metallic character, with a magnetic moment of 1.0 μB per Fe atom and a large ferromagnetic stabilization energy of 33 meV, an order of magnitude larger than in other semiconductors, with correspondingly high Curie temperatures. These results, combined with diamond's unique properties, demonstrate that Fe doped p-type diamond is likely to be a highly suitable candidate material for spintronics applications.
Fabrication of faceted nanopores in magnesium
Authors: Wu Shujing , Cao Fan , Zheng He , Sheng Huaping , Liu Chun , Liu Yu , Zhao Dongshan , Wang Jianbo
Published: December 2013

In this paper, using high resolution transmission electron microscopy, we showed the fabrication of faceted nanopores with various shapes in magnesium by focused electron beam (e-beam). The characteristics of nanopore shapes and the crystallographic planes corresponding to the edges of the nanopores were discussed in detail. Interestingly, by manipulating the e-beam (e.g., irradiation direction and duration), the nanopore shape and size could be effectively controlled along different directions. Our results provide important insight into the nanopore patterning in metallic materials and are of fundamental importance concerning the relevant applications, such as nanopore-based sensor, etc.
Enhanced thermoelectric figure of merit in nanostructured ZnO by nanojunction effect
Authors: Wu Zi-Hua , Xie Hua-Qing , Zhai Yong-Biao
Published: December 2013

We report in this letter the synthesis and thermoelectric properties of Zn1−xNixO/polyparaphenylene (Zn1−xNixO/PPP) organic-inorganic hybrid materials. Compared to the inorganic ZnO-based materials, hybrid materials exhibit dual effects of increased power factor consistent with the molecular junction effect and a reduction in thermal conductivity by the incorporation of conductive PPP. As a result, the greatest ZT = 0.54 of hybrid materials was obtained at 1173 K, which corresponds to a 6-fold enhancement compared to that of the best inorganic Zn0.97Ni0.03O sample (ZT = 0.09) at 1000 K.
Band gaps in InN/GaN superlattices: Nonpolar and polar growth directions
Authors: Gorczyca I. , Skrobas K. , Suski T. , Christensen N. E. , Svane A.
Published: December 2013

The electronic structures of nonpolar short-period InN/GaN superlattices (SLs) grown in the wurtzite a- and m-directions have been calculated and compared to previous calculations for polar superlattices (grown in the c-direction). The variation of the band gaps with the composition (m, n) of the mInN/nGaN unit cells of the superlattices was examined. The band structures were obtained by self-consistent calculations based on the local density approximation to the density functional theory using the Linear-Muffin-Tin-Orbital method with a semi-empirical correction for the band gaps. The calculated band gaps and their pressure coefficients for nonpolar superlattices are similar to those calculated for bulk InGaN alloys with an equivalent In/Ga concentration ratio. This is very different from what has been found in polar superlattices where the band gaps are much smaller and vanish when the number m of InN layers in the unit cell exceeds three. A strong internal electric field is responsible for this behavior of polar structures. Experimental photoluminescence data for polar SLs agree very well with gaps calculated for the nonpolar structures. It is suggested that this is caused by screening of the electric field in the polar structures by carriers originating from unintentional defects.
Direct measurement of the kinetics of volume and enthalpy relaxation of an Au-based bulk metallic glass
Authors: Bünz J. , Wilde G.
Published: December 2013

Structural relaxation of glasses below their glass transition is a well-studied phenomenon that still poses several open issues. With the advent of bulk metallic glasses with exceptionally low glass transition temperatures, new options are available that are based on the experimental assessment of the time dependence of several different thermodynamic quantities by direct measurements with high accuracy. In this contribution the first direct measurement of the isothermal relaxation of the volume and the enthalpy of an Au-based bulk metallic glassformer are reported and discussed with respect of the characteristics describing the underlying processes.
Reduction of NOx emission on NiCrAl-Titanium Oxide coated direct injection diesel engine fuelled with radish (Raphanus sativus) biodiesel
Authors: Ravikumar V. , Senthilkumar D.
Published: December 2013

The main aim of this study is the experimental investigation of single cylinder DI diesel engine with and without coating. Diesel and radish (Raphanus sativus) oil Methyl Ester are used as fuels and the results are compared to find the effect of biodiesel in a thermal barrier coating engine. For this purpose, engine cylinder head, valves, and piston crown are coated with 100 μm of nickel-chrome-aluminium bond coat and 450 μm of TiO2 by the plasma spray method. Radish oil methyl ester is produced by the transesterification process method. From the experimental investigation, slight increase in specific fuel consumption in thermal barrier coating engine is observed when compared with the uncoated engine, whereas NOx, HC, Smoke, and CO emissions decreased with coated engine for all test fuels used in the coated engine when compared with that of the uncoated engine.
Amplification of interference color by using liquid crystal for protein detection
Authors: Zhu Qingdi , Yang Kun-Lin
Published: December 2013

Micrometer-sized, periodic protein lines printed on a solid surface cause interference color which is invisible to the naked eye. However, the interference color can be amplified by using a thin layer of liquid crystal (LC) covered on the surface to form a phase diffraction grating. Strong interference color can thus be observed under ambient light. By using the LC-amplified interference color, we demonstrate naked-eye detection of a model protein—immunoglobulin G (IgG). Limit of detection can reach 20 μg/ml of IgG without using any instrumentation. This detection method is potentially useful for the development of low-cost and portable biosensors.
Surface morphology and electrical transport of rapid thermal annealed chromium-doped indium zinc oxides: The influence of zinc interstitials and out-diffusion
Authors: Hsu C. Y.
Published: December 2013

We investigate the complex impedance (CI) spectra of chromium-doped indium zinc oxide (CIZO) films with different rapid thermal annealing (RTA) temperatures. The CI spectra drawn from the impedance contributions of Zn-O and In-O bondings in CIZO films were analyzed by two sets of parallel resistance and capacitance components in series. The result demonstrates that zinc interstitials controls electron concentration and transition of electrical transport from semiconducting to metallic. At higher RTA temperature, high-density zinc interstitial promotes Zn atom diffusion from the surface, modifying surface morphology.
Study of microstructure and semiconductor to metallic conductivity transition in solid state sintered Li0.5Mn0.5Fe2O4−δ spinel ferrite
Authors: Bhowmik R. N. , Vijayasri G.
Published: December 2013

Li0.5Mn0.5Fe2O4 ferrite has been prepared by solid state sintering route. XRD pattern showed single phased cubic spinel structure. The samples exhibited typical character of plastoferrite with ring shaped surface microstructure. New feature observed in the present ferrite is the frequency activated conductivity transition from semiconductor to metallic state above 800 K. The increase of conductivity with frequency in the semiconducting regime follows Jonscher power law, while decrease of conductivity in metallic regime obeys Drude equation. The conductivity in semiconductor regime has been understood by hopping mechanism of localized charge carriers among the cations in B sites of cubic spinel structure. At higher temperatures, overlapping of electronic orbitals from neighbouring ions and free particle like motion of lighter Li+ ions among interstitial lattices contributed metallic conductivity. The samples provided evidence of localized nature of the charge carriers at lower temperatures and increasing delocalized character with the increase of measurement temperature. From application point of view, such ferrites behave as semiconductor at low temperature and allow electromagnetic wave to pass through, but transform into a metallic reflector with negative dielectric constant at high temperature.
Photonic crystal slab quantum cascade detector
Authors: Reininger Peter , Schwarz Benedikt , Harrer Andreas , Zederbauer Tobias , Detz Hermann , Maxwell Andrews Aaron , Gansch Roman , Schrenk Werner , Strasser Gottfried
Published: December 2013

In this Letter, we demonstrate the design, fabrication, and characterization of a photonic crystal slab quantum cascade detector (PCS-QCD). By employing a specifically designed resonant cavity, the performance of the photodetector is improved in three distinct ways. The PCS makes the QCD sensitive to surface normal incident light. It resonantly enhances the photon lifetime inside the active zone, thus increasing the photocurrent significantly. And, the construction form of the device inherently decreases the noise. Finally, we compare the characteristics of the PCS-QCD to a PCS - quantum well infrared photodetector and outline the advantages for certain fields of applications.
A two-dimensional broadband vibration energy harvester using magnetoelectric transducer
Authors: Yang Jin , Wen Yumei , Li Ping , Yue Xihai , Yu Qiangmo , Bai Xiaoling
Published: December 2013

In this study, a magnetoelectric vibration energy harvester was demonstrated, which aims at addressing the limitations of the existing approaches in single dimensional operation with narrow working bandwidth. A circular cross-section cantilever rod, not a conventional thin cantilever beam, was adopted to extract vibration energy in arbitrary in-plane motion directions. The magnetic interaction not only resulted in a nonlinear motion of the rod with increased frequency bandwidth, but also contributed to a multi-mode motion to exhibit double power peaks. In energy harvesting with in-plane directions, it showed a maximum bandwidth of 4.4 Hz and power of 0.59 mW, with acceleration of 0.6 g (with g = 9.8 m s−2).
Autophagy proteins stabilize pathogen-containing phagosomes for prolonged MHC II antigen processing
Authors: Romao Susana , Gasser Nathalie , Becker Andrea C. , Guhl Bruno , Bajagic Milica , Vanoaica Danusia , Ziegler Urs , Roesler Joachim , Dengjel Jörn , Reichenbach Janine , Münz Christian
Published: December 2013

Antigen preservation for presentation is a hallmark of potent antigen-presenting cells. In this paper, we report that in human macrophages and dendritic cells, a subset of phagosomes gets coated with Atg8/LC3, a component of the molecular machinery of macroautophagy, and maintains phagocytosed antigens for prolonged presentation on major histocompatibility complex class II molecules. These Atg8/LC3-positive phagosomes are formed around the antigen with TLR2 agonists and require reactive oxygen species production by NOX2 for their generation. A deficiency in the NOX2-dependent formation of these antigen storage phagosomes could contribute to compromise antifungal immune control in chronic granulomatous disease patients.
Tuning solubility and stability of hydrochlorothiazide co-crystals
Authors: Sanphui Palash , Rajput Lalit
Published: December 2013

Hydrochlorothiazide (HCT), C7H8ClN3O4S2, is a diuretic BCS (Biopharmaceutics Classification System) class IV drug which has primary and secondary sulfonamide groups. To modify the aqueous solubility of the drug, co-crystals with biologically safe co-formers were screened. Multi-component molecular crystals of HCT were prepared with nicotinic acid, nicotinamide, succinamide,p-aminobenzoic acid, resorcinol and pyrogallol using liquid-assisted grinding. The co-crystals were characterized by FT-IR spectroscopy, powder X-ray diffraction (PXRD) and differential scanning calorimetry. Single crystal structures were obtained for four of them. The N—H...O sulfonamide catemer synthons found in the stable polymorph of pure HCT are replaced in the co-crystals by drug-co-former heterosynthons. Isostructural co-crystals with nicotinic acid and nicotinamide are devoid of the common sulfonamide dimer/catemer synthons. Solubility and stability experiments were carried out for the co-crystals in water (neutral pH) under ambient conditions. Among the six binary systems, the co-crystal withp-aminobenzoic acid showed a sixfold increase in solubility compared with pure HCT, and stability up to 24 h in an aqueous medium. The co-crystals with nicotinamide, resorcinol and pyrogallol showed only a 1.5–2-fold increase in solubility and transformed to HCT within 1 h of the dissolution experiment. An inverse correlation is observed between the melting points of the co-crystals and their solubilities.
Microclimate modelling at macro scales: a test of a general microclimate model integrated with gridded continental‐scale soil and weather data
Authors: Kearney Michael R. , Shamakhy Alireza , Tingley Reid , Karoly David J. , Hoffmann Ary A. , Briggs Peter R. , Porter Warren P.
Published: December 2013

The microclimate experienced by organisms is determined by local weather conditions. Yet the environmental data available for predicting the effect of climate on the distribution and abundance of organisms are typically in the form of long‐term average monthly climate measured at standardized heights above the ground.

Here, we demonstrate how hourly microclimates can be modelled mechanistically over decades at the continental scale with biologically suitable accuracy.

We extend the microclimate model of the software package niche mapper to capture spatial and temporal variation in soil thermal properties and integrate it with gridded soil and weather data for Australia at 0·05° resolution.

When tested against historical observations of soil temperature, the microclimate model predicted 85% of the variation in hourly soil temperature across 10 years from the surface to 1 m deep with an accuracy of 2–3·3 °C (c. 10% of the temperature range at a given depth) across an extremely climatically diverse range of sites.

This capacity to accurately and mechanistically predict hourly local microclimates across continental scales creates new opportunities for understanding how organisms respond to changes in climate.
Do Motives Matter in Male Circumcision? ‘Conscientious Objection’ Against the Circumcision of a Muslim Child with a Blood Disorder
Authors: Ahmad Ayesha
Published: December 2013

Whilst there have been serious attempts to locate the practice of male circumcision for religious motives in the context of the (respective) religion's narrative and community, the debate, when referring to a clinical context, is often more nuanced. This article will contribute further to the debate by contextualising the Islamic practice of male circumcision within the clinical setting typical of a contemporary hospital. It specifically develops an additional complication; namely, the child has a pre‐existing blood disorder. As an approach to contributing to the circumcision debate further, the ethics of a conscientious objection for secular motives towards a religiously‐motivated clinical intervention will be explored. Overall, the discussion will provide relevance for such debates within the value‐systems of a multi‐cultural society. This article replicates several approaches to deconstructing a request for conscientious refusal of non‐therapeutic circumcision by a Clinical Ethics Committee (CEC), bringing to light certain contradictions that occur in normatively categorizing motives for performing the circumcision.
‘Oh my god, we're not doing nothing’: Young people's experiences of spatial regulation
Authors: Gray Debra , Manning Rachel
Published: December 2013

Social psychologists have become increasingly concerned with examining the ways in which social practices are interrelated with their location. Critical perspectives have highlighted the traditional lack of attention given to both the collective aspects of spatial identities, together with the discursive practices that construct the relationships between people and places. In this article, we draw together the developing discursive work on place with work on children's geographies, in order to examine young people's accounts of spatial regulation. Adopting a discursive approach to the analysis of focus group discussion, we illustrate a variety of concerns managed in relation to spatial practices by 41 young people living in a large city in the South of England. Our findings suggest that everyday use of public space by young people is constructed at a nexus of competing concerns around childhood/adulthood, freedom, and citizenship, and illustrate the dynamic nature of place, and its regulation, as a resource for constructing identities.
Holocene fire disturbance in the boreal forest of central Sweden
Authors: Brown Kendrick J. , Giesecke Thomas
Published: December 2013

Holocene fire disturbance and vegetation history were reconstructed using macroscopic charcoal and pollen accumulation rates from two lake sediment records (Holtjärnen and Klotjärnen) collected in the boreal forest of central Sweden. The records were used to examine the potential drivers associated with changes in fire regime. Climate, vegetation and human activity were all identified as factors variously influencing the fire regime. In the early Holocene, near bicentennial fire return intervals were regionally widespread, suggesting that fire disturbance was largely regulated by climate at that time. In the mid‐ and late Holocene, vegetation exerted an important control on the fire regime. During the mid‐Holocene, the expansion of thermophilous broadleaf vegetation offset the influence of warmer climate by altering the local microclimate and by changing the structure and flammability of the available fuels. During the transition to the late Holocene, thermophilous vegetation decreased in abundance and Pinus increased, resulting in a more flammable forest even though the climate was cooling and moistening. Fire disturbance correspondingly increased. The modern boreal forest was established in the late Holocene as Picea expanded regionally as the climate cooled, moistened, and became increasingly continental. Although no change in the frequency of fire was apparent at this time, increased stand densities likely facilitated greater fuel consumption in subsequent fires. Within the last millennium, human action markedly modified the forested landscape, altering the fire regime.
Linking lack of care in childhood to anxiety disorders in emerging adulthood: the role of attachment styles
Authors: Schimmenti Adriano , Bifulco Antonia
Published: December 2013

Background

Emotional neglect can be characterized as cold or critical parenting and denotes a parent intentionally or unintentionally overlooking the signs that a child needs comfort or attention and ignoring its emotional needs. Parental emotional neglect is widely posited as an antecedent of anxiety disorder, with attachment researchers arguing for anxious–ambivalent attachment style as a mediating factor.

Method

Childhood experience of neglect and abuse, including antipathy (cold, critical parenting), attachment styles, and anxiety disorders were assessed in a high‐risk sample of 160 adolescents and young adults by means of interview measures.

Results

Antipathy was associated with 12‐month prevalence of anxiety disorders in the sample. Anxious–ambivalent attachment scores statistically mediated the relationship between antipathy and anxiety disorders.

Conclusions

Clinicians treating anxiety disorders in youths need to consider that emotional neglect in childhood in the form of antipathy could lead to anxious–ambivalent internal working models operating around fear of rejection and fear of separation.
Gist of Dr. Katsusaburo Yamagiwa's papers entitled “Experimental study on the pathogenesis of epithelial tumors” (I to VI reports)
Authors: Fujiki Hirota
Published: December 2013

The concept of cancer and inflammation has a long history. Virchow's irritation theory based on human cancer engendered the essential role of inflammation in carcinogenesis. Drs. Yamagiwa and Ichikawa first published a comprehensive paper entitled “Experimental study on the pathogenesis of epithelial tumors” (I report) in 1915 in German, and went on to publish five more reports (1915–1924) under the same title. They succeeded in demonstrating that inflammation is an important carcinogenic factor, and the mechanisms are now being investigated by numerous scientists all over the world. In order to introduce Yamagiwa's work to modern cancer researchers, the essentials of their six reports have been translated into English as a short review. Scientists' comments on Yamagiwa's contribution are attached by way of introduction.
Mothers' Cognitive References to 2‐Year‐Olds Predict Theory of Mind at Ages 6 and 10
Authors: Ensor Rosie , Devine Rory T. , Marks Alex , Hughes Claire
Published: December 2013

Mothers' mental‐state references predict individual differences in preschoolers' false‐belief (FB) understanding; less is known about the origins of corresponding variation in school‐age children. To address this gap, 105 children completed observations with their mothers at child ages 2 and 6, threeFBtasks and a verbal comprehension test at age 3, and fiveFBtasks at age 6. Seventy‐seven of these children completed five Strange Stories at age 10. Individual differences in mothers' cognitive references at child age 2 predicted variation in children'sFBunderstanding at age 6 and Strange Stories scores at age 10 (controlling for number of mothers' turns and children's mental‐state references, verbal comprehension andFBunderstanding at age 3, and mothers' cognitive references at child age 6).