bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping the near-field propagation of surface plasmons on terahertz metasurfaces
Authors: Xu Yuehong , Zhang Xueqian , Tian Zhen , Gu Jianqiang , Ouyang Chunmei , Li Yanfeng , Han Jiaguang , Zhang Weili
Published: July 2015

Controlling the propagation of surface plasmon polaritons is essential in developing highly integrated photonic devices. By using near-field scanning terahertz microscopy, we experimentally demonstrate that polarization-controlled tunable surface plasmons (SPs) could be directionally excited on a metal surface with carved columns of aperture resonators under special arrangement. The experimental results reveal that terahertz SPs could be unidirectionally launched in opposite directions owning to destructive and constructive interferences on the two sides with circularly polarized incident waves of opposite handedness. Meanwhile, the linearly polarized wave is able to excite the terahertz SPs along either side of the structures. The presented results would be useful to implement functional terahertz plasmonic devices.
Realization of multifunctional shape-memory ferromagnets in all-d-metal Heusler phases
Authors: Wei Z. Y. , Liu E. K. , Chen J. H. , Li Y. , Liu G. D. , Luo H. Z. , Xi X. K. , Zhang H. W. , Wang W. H. , Wu G. H.
Published: July 2015

Heusler ferromagnetic shape-memory alloys (FSMAs) normally consist of transition-group d-metals and main-group p-elements. Here, we report the realization of FSMAs in Heusler phases that completely consist of d metals. By introducing the d-metal Ti into NiMn alloys, cubic B2-type Heusler phase is obtained and the martensitic transformation temperature is decreased efficiently. Strong ferromagnetism is established by further doping Co atoms into the B2-type antiferromagnetic Ni-Mn-Ti austenite. Based on the magnetic-field-induced martensitic transformations, collective multifunctional properties are observed in Ni(Co)-Mn-Ti alloys. The d metals not only facilitate the formation of B2-type Heusler phases but also establish strong ferromagnetic coupling and offer the possibility to tune the martensitic transformation.
Study of oscillation performance characteristics of unidirectional photorefractive ring resonators: Cavity detuning dependence
Authors: Singh Ruchi , Yadav R. A. , Singh D. P.
Published: July 2015

Single unidirectional photorefractive ring resonator (SUPRR) and coupled unidirectional photorefractive ring resonator (CUPRR) were considered with BaTiO3 and LiNbO3 crystals as inter-cavity photorefractive media. The relative oscillation intensity and oscillation frequency shift of two SUPRRs with BaTiO3 and LiNbO3 crystals in their cavities, and four CUPRRs with BaTiO3-BaTiO3, LiNbO3-LiNbO3, BaTiO3-LiNbO3 and LiNbO3-BaTiO3 combinations were analysed relative to cavity detuning parameters and compared the oscillation performance of SUPRR with that of CUPRR. In SUPRR, maximum value of relative oscillation intensity is found for BaTiO3 as compared to that of LiNbO3 for zero cavity detuning. In CUPRR, the oscillation intensity in secondary cavity increases with increasing cavities detuning whereas in primary cavity it decreases with increasing cavities detuning. Major finding of this study is that the BaTiO3-LiNbO3 combination of the coupled system provides the highest relative oscillation intensity.
Synergistic effect of alloying elements doping and external pressure on the elastic property of Ni3Al: A first-principles study
Authors: Li C. , Shang J. , Kou L. , Yue Z.
Published: July 2015

In this paper, the basic electronic structures and elastic properties of Ni3Al doping with alloying elements (Re, Cr, and Mo) under different pressures have been investigated using first-principles calculations based on density functional theory. It is shown that both alloying elements and external applied pressure contribute positively to the elastic properties of Ni3Al, and the configurations of the compounds remain almost unchanged. The calculated elastic constants and moduli increase linearly with the pressure increasing from 0 and 40 GPa. Among the alloying elements studied in the present work, Re exhibits the most significant effect compared with the other elements, showing its practical importance. Especially, if both alloying elements doping and pressure effects are considered simultaneously, which has not been considered previously, the studied compounds exhibit an even better elastic property than the simple superposition of the two influences. Such synergistic effect demonstrates promising applications of Ni-based single crystal superalloys in possible extreme mechanical environments.
Exchange spring behaviour in SrFe12O19-CoFe2O4 nanocomposites
Authors: Roy Debangsu , Anil Kumar P. S.
Published: July 2015

Nanocomposites of hard (SrFe12O19) and soft ferrite (CoFe2O4) are prepared by mixing individual ferrite components at appropriate weight ratio and subsequent heat treatment. The magnetization of the composites showed hysteresis loop that is characteristic of the exchange spring system. The variation of Jr/Jr(∞) vs. Jd/ Jr(∞) for these nanocomposites are investigated to understand the presence of both the interacting field and the disorder in the system. This is further corroborated with the First Order Reversal Curve analysis (FORC) on the nanocomposites of 1:4 (Cobalt Ferrite: Strontium Ferrite) and 1:16 (Cobalt Ferrite: Strontium Ferrite). The FORC distribution reveals that the pinning mechanism is stronger in the nanocomposite of 1:4 compared to 1:16. However, the nanocomposite of 1:16 exhibit superior exchange coupling strength in contrast to 1:4. The asymmetric nature of the FORC distribution at Hc = 0 Oe for both the nanocomposites validates the intercoupling between the reversible and irreversible magnetization.
Composite Cathode Based on Redox-Reversible Nb2TiO7 for Direct High-Temperature Steam Electrolysis
Authors: Li Shi-song , Cheng Ji-gui , Zhang Xu-cheng , Wang Yu , Xie Kui
Published: July 2015

Ni/YSZ fuel electrodes can only operate under strongly reducing conditions for steam electrolysis in an oxide-ion-conducting solid oxide electrolyzer (SOE). In atmosphere with a low content of H2 or without H2, cathodes based on redox-reversible Nb2TiO7 provide a promising alternative. The reversible changes between oxidized Nb2TiO7 and reduced Nb1.33Ti0.67O4 samples are systematically investigated after redox-cycling tests. The conductivities of Nb2TiO7 and reduced Nb1.33Ti0.67O4 are studied as a function of temperature and oxygen partial pressure and correlated with the electrochemical properties of the composite electrodes in a symmetric cell and SOE at 830 °C. Steam electrolysis is then performed using an oxide-ion-conducting SOE based on a Nb1.33Ti0.67O4 composite fuel electrode at 830 °C. The current-voltage and impedance spectroscopy tests demonstrate that the reduction and activation of the fuel electrode is the main process at low voltage; however, the steam electrolysis dominates the entire process at high voltages. The Faradic efficiencies of steam electrolysis reach 98.9% when 3%H2O/Ar/4%H2 is introduced to the fuel electrode and 89% for that with introduction of 3%H2O/Ar.
Desulfurization Mechanism of Cysteine in Synthesis of Polypeptides
Authors: Tian Yan , Wang Li , Shi Jing , Yu Hai-zhu
Published: July 2015

The free-radical-based selective desulfurization of cysteine residue is an efficient protocol to achieve ligations at alanine sites in the synthesis of polypeptide and proteins. In this work, the mechanism of desulfurization process has been studied using the density functional theory methods. According to the calculation results, the desulfurization of the thiol group occurs via a three-steps mechanism: the abstraction of hydrogen atom on the thiol group with the radical initiator VA-044 (2,2′-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride), the removal of S atom under the reductant TCEP (tris(2-carboxyethyl)phosphine), and the formation of RH molecule (with the regeneration of RS radical). The second step (desulfurization step) is the rate-determining step, and the adduct t-BuSH facilitates the desulfurization of cysteine via benefiting the formation of the precursor of the desulfurization step.
Biodiesel Production from Waste Cooking Oil over Mesoporous SO42−/Zr-SBA-15
Authors: Zhang Ji-long , Lei Zhi-jie , Zhang Xiao-chao , Zhang Qi , Yi Qun , Li Rui-feng
Published: July 2015

Biodiesel production from waste cooking oils over SO42−/Zr-SBA-15 catalyst was successfully carried out and investigated. SO42−/Zr-SBA-15 catalyst was prepared by one-step process using anhydrous zirconium nitrate as zirconium resource, and endowed with the strong Lewis acid sites formed by supporting the zirconium species onto the SBA-15 surface. The as-prepared SO42−/Zr-SBA-15 showed excellent triglyceride conversion efficiency of 92.3% and fatty acid methyl esters (FAME) yield of 91.7% for the transesterification of waste cooking oil with methanol under the optimized reaction conditions: the methanol/oil molar ratio of 30, the reaction temperature of 160 °C, the reaction time of 12 h and 10wt% of catalyst. It was noticed that the as-prepared SO42−/Zr-SBA-15 materials with the higher area surface of mesoporous framework and the surface acidity displayed excellent stability and reusability, maintaining high FAME yield of (74±1)% after seven runs of reaction.
Ab initio Predictions of Structural and Thermodynamic Properties of Zr2AlC Under High Pressure and High Temperature
Authors: Luo Fen , Guo Zhi-cheng , Zhang Xiu-lu , Yuan Chang-ying , Cai Ling-cang
Published: July 2015

The structural and thermodynamic properties of Zr2AlC at high pressure and high temperature are investigated by first principles density functional theory method. The calculated lattice parameters of Zr2AlC are in good agreement with the available theoretical data. The pressure dependences of the elastic constants, bulk modulus, shear modulus, Young's modulus, and Vickers hardness of Zr2AlC are successfully obtained. The elastic anisotropy is examined through the computation of the direction dependence of Young's modulus. By using the quasiharmonic Debye model, the thermodynamic properties including the Debye temperature, heat capacity, volume thermal expansion coefficient, and Grüneisen parameter at high pressure and temperature are predicted for the first time.
Multi-Physics Modeling of Solid Oxide Fuel Cell Fueled by Methane and Analysis of Carbon Deposition
Authors: Wang Bao-xuan , Jiang Zhu , Lin Zi-jing
Published: July 2015

Internal reformation of low steam methane fuel is important for the high efficiency and low cost operation of solid oxide fuel cell. Understanding and overcoming carbon deposition is crucial for the technology development. Here a multi-physics model is established for the relevant experimental cells. Balance of electrochemical potentials for the electrochemical reactions, generic rate expression for the methane steam reforming, dusty gas model in a form of Fick's model for anode gas transport are used in the model. Excellent agreement between the theoretical and experimental current-voltage relations is obtained, demonstrating the validity of the proposed theoretical model. The steam reaction order in low steam methane reforming reaction is found to be 1. Detailed information about the distributions of physical quantities is obtained by the numerical simulation. Carbon deposition is analyzed in detail and the mechanism for the coking inhibition by operating current is illustrated clearly. Two expressions of carbon activity are analyzed and found to be correct qualitatively, but not quantitatively. The role of anode diffusion layer on reducing the current threshold for carbon removal is also explained. It is noted that the current threshold reduction may be explained quantitatively with the carbon activity models that are only qualitatively correct.
Theoretical Analysis on Optical Limiting Properties of Newly Synthesized Graphene Oxide-Porphyrin Composites
Authors: Zhang Yu-jin , Yang Wen-jing , Fan Jian-zhong , Song Yu-zhi , Wang Chuan-kui
Published: July 2015

Optical limiting (OL) properties and two-photon absorption (TPA) of a series of covalently linked graphene oxide-porphyrin composite materials have been investigated by numerically solving the rate equations and field intensity equation with an iterative predictor-corrector finite-difference time-domain technique in nanosecond time domain. Our results show that graphene oxide-porphyrin composites exhibit enhanced OL behavior and possess larger TPA cross section compared with individual porphyrins. Interestingly, unlike the previous result that porphyrin with heavier central metal shows better nonlinear abilities than that without metal substitute, graphene oxide-metal free porphyrin composite has stronger nonlinear absorption properties compared with graphene oxide-metal porphyrin composite. The computational results are in reasonable agreement with the experimental ones. Special attention has been paid to the influence of thickness of the medium and pulse width on TPA cross sections, which presents that larger TPA cross sections are obtained as the medium is thicker or the pulse duration is wider.
Reaction Kinetics of Trans-Sobrerol and 8-p-Menthen-1,2-diol with Hydroxyl Radical in Aqueous Solution: A Combined Experimental and Theoretical Study
Authors: Long Yan , Tong Xin , Ma Tong-mei , Wang Li-ming
Published: July 2015

Trans-sobrerol (Sob) and 8-p-menthen-1,2-diol (Limo-diol) are the primary products in the atmospheric oxidation of β-pinene and limonene, respectively. Because of their low volatility, they associate more likely to the liquid particles in the atmosphere, where they are subject to the aqueous phase oxidation by the atmospheric oxidants. In this work, through experimental and theoretical study, we first provide the rate constants of Sob and Limo-diol reacting with hydroxyl radical (·OH) in aqueous solution at room temperature of 304±3 K and 1 atm pressure, which are (3.05±0.5)×109 and (4.57±0.2)×109 L/(mol·s), respectively. Quantum chemistry calculations have also been employed to demonstrate the solvent effect on the rate constants in aqueous phase and the calculated results agree well with the measurements. Some reaction products have been identified based on liquid chromatography combined with mass spectroscopy and theoretical calculations.
Population Genetic Structure of Southern Flounder Inferred from Multilocus DNA Profiles
Authors: Wang Verena H. , McCartney Michael A. , Scharf Frederick S.
Published: July 2015

Determination of stock structure is an important component of fisheries management; incorporation of molecular genetic data is an effective method for assessing differentiation among putative populations. We examined genetic variation in Southern Flounder Paralichthys lethostigma within and between the U.S. South Atlantic and Gulf of Mexico basins to improve our understanding of the scale of population structure in this wide-ranging species. Analysis of amplified fragment length polymorphism (AFLP) fingerprints and analysis of mitochondrial DNA (mtDNA) control region sequences found clear divergence between ocean basins. Based on mtDNA sequences, no genetic differentiation was detected within the U.S. South Atlantic at spatial scales that were broad (among states: North Carolina, South Carolina, Georgia, and Florida) or fine (among estuarine regions within North Carolina). Increased genetic resolution was observed with AFLP fingerprint data, and we found significant subdivision between nearly all Southern Flounder geographic populations, suggesting the presence of finer-scale genetic population structure within the U.S. South Atlantic. However, AFLP genetic cluster analysis also revealed evidence for a high degree of mixing within the Atlantic basin; patterns of variation, which included genetic similarity between South Carolina and Gulf of Mexico samples, were not aligned closely with geography. We examined the partitioning of genetic variation among groups by using analyses of molecular variance and found no evidence that North Carolina Southern Flounder, which are managed on the state level as a unit stock, are differentiated from the remainder of U.S. South Atlantic Southern Flounder. Our findings indicate only weak structure and the potential for basinwide mixing among Atlantic Southern Flounder, suggesting that cooperation among U.S. South Atlantic states will be essential for the effective assessment of stock dynamics and future management plans.
Contributions of epsinR and gadkin to clathrin-mediated intracellular trafficking
Authors: Hirst Jennifer , Edgar James R. , Borner Georg H. H. , Li Sam , Sahlender Daniela A. , Antrobus Robin , Robinson Margaret S.
Published: July 2015

The precise functions of most of the proteins that participate in clathrin-mediated intracellular trafficking are unknown. We investigated two such proteins, epsinR and gadkin, using the knocksideways method, which rapidly depletes proteins from the available pool by trapping them onto mitochondria. Although epsinR is known to be an N-ethylmaleimide–sensitive factor attachment protein receptor (SNARE)-specific adaptor, the epsinR knocksideways blocked the production of the entire population of intracellular clathrin-coated vesicles (CCVs), suggesting a more global function. Using the epsinR knocksideways data, we were able to estimate the copy number of all major intracellular CCV proteins. Both sides of the vesicle are densely covered, indicating that CCVs sort their cargo by molecular crowding. Trapping of gadkin onto mitochondria also blocked the production of intracellular CCVs but by a different mechanism: vesicles became cross-linked to mitochondria and pulled out toward the cell periphery. Both phenotypes provide new insights into the regulation of intracellular CCV formation, which could not have been found using more conventional approaches.
Karect: accurate correction of substitution, insertion and deletion errors for next-generation sequencing data
Authors: Allam Amin , Kalnis Panos , Solovyev Victor
Published: July 2015

Motivation: Next-generation sequencing generates large amounts of data affected by errors in the form of substitutions, insertions or deletions of bases. Error correction based on the high-coverage information, typically improves de novo assembly. Most existing tools can correct substitution errors only; some support insertions and deletions, but accuracy in many cases is low.

Results: We present Karect, a novel error correction technique based on multiple alignment. Our approach supports substitution, insertion and deletion errors. It can handle non-uniform coverage as well as moderately covered areas of the sequenced genome. Experiments with data from Illumina, 454 FLX and Ion Torrent sequencing machines demonstrate that Karect is more accurate than previous methods, both in terms of correcting individual-bases errors (up to 10% increase in accuracy gain) and post de novo assembly quality (up to 10% increase in NGA50). We also introduce an improved framework for evaluating the quality of error correction.

Availability and implementation: Karect is available at: http://aminallam.github.io/karect.

Contact:  amin.allam@kaust.edu.sa

Supplementary information:  Supplementary data are available at Bioinformatics online.
Readability assessment of patient-provider electronic messages in a primary care setting
Authors: Mirsky Jacob B , Tieu Lina , Lyles Courtney , Sarkar Urmimala
Published: July 2015

Background The high prevalence of limited health literacy among patients threatens the success of secure electronic messaging between patients from diverse populations and their providers.

Objective The purpose of this study is to generate hypotheses about the readability of patient and provider electronic messages.

Methods We collected 31 patient-provider e-mail exchanges ( n = 119 total messages) from a safety-net primary care clinic. We compared the messages’ mean word count and Flesch-Kincaid Grade Levels (FKGLs), calculated the frequency of provider messages below an FKGL = 8, and assessed readability concordance between patients’ and providers’ messages.

Results Patients used more words in their initial e-mails compared to providers, but the FKGLs were similar, and 68% of provider messages were written below an FKGL = 8. Of 31 exchanges, 9 (29%) contained at least one patient message with an FKGL > 3 grade levels lower than the corresponding provider message(s).

Conclusion Our study demonstrates that most providers are able to respond to patient electronic messages with a matching reading level.
Brain Maturation in Neonatal Rodents Is Impeded by Sevoflurane Anesthesia
Authors: Makaryus Rany , Lee Hedok , Feng Tian , Park June-Hee , Nedergaard Maiken , Jacob Zvi , Enikolopov Grigori , Benveniste Helene
Published: July 2015

AbstractAbstract

Sevoflurane reduced the increase in N-acetylaspartate (NAA) that is apparent in the normal brain from postnatal day (PND) 8 to PND9. The relevant reduction in NAA was not observed in rodents exposed to sevoflurane at PND15. Sevoflurane increased neuronal apoptosis when exposure occurred at PND7 but not at PND15. Apoptosis and reduction in NAA were correlated. The data indicate that magnetic resonance spectroscopy can detect subtle changes in brain metabolism on anesthetic exposure. Importantly, magnetic resonance spectroscopy can be used to noninvasively evaluate anesthetic neurotoxicity in the developing brain.

Background:

A wealth of data shows neuronal demise after general anesthesia in the very young rodent brain. Herein, the authors apply proton magnetic resonance spectroscopy (1HMRS), testing the hypothesis that neurotoxic exposure during peak synaptogenesis can be tracked via changes in neuronal metabolites.

Methods:

1HMRS spectra were acquired in the brain (thalamus) of neonatal rat pups 24 and 48 h after sevoflurane exposure on postnatal day (PND) 7 and 15 and in unexposed, sham controls. A repeated measure ANOVA was performed to examine whether changes in metabolites were different between exposed and unexposed groups. Sevoflurane-induced neurotoxicity on PND7 was confirmed by immunohistochemistry.

Results:

In unexposed PND7 pups (N = 21), concentration of N-acetylaspartate (NAA; [NAA]) increased by 16% from PND8 to PND9, whereas in exposed PND7 pups (N = 19), [NAA] did not change and concentration of glycerophosphorylcholine and phosphorylcholine ([GPC + PCh]) decreased by 25%. In PND15 rats, [NAA] increased from PND16 to PND17 for both the exposed (N = 14) and the unexposed (N = 16) groups. Two-way ANOVA for PND7 pups demonstrated that changes over time observed in [NAA] (P = 0.031) and [GPC + PCh] (P = 0.024) were different between those two groups.

Conclusions:

The authors demonstrated that normal [NAA] increase from PND8 to PND9 was impeded in sevoflurane-exposed rats when exposed at PND7; however, not impeded when exposed on PND15. Furthermore, the authors showed that noninvasive 1HMRS is sufficiently sensitive to detect subtle differences in developmental time trajectory of [NAA]. This is potentially clinically relevant because 1HMRS can be applied across species and may be useful in providing evidence of neurotoxicity in the human neonatal brain.
Introducer Development for Coronary Sinus Access from Parasternal Mediastinotomy
Authors: Spotnitz Henry M. , Yeager Keith J. , Cabreriza Santos E. , Vunjak-Novakovic Gordana , Wang Daniel Y. , Pearson Gregory D.N.
Published: July 2015

Objective

Right parasternal mediastinotomy with right atriotomy has been used clinically for pacemaker insertion. A similar approach might facilitate access to the coronary sinus for biventricular pacing and other manipulations when more conventional approaches are not feasible. The primary barrier to this is lack of appropriate introducers and techniques.

Methods

Anatomically derived introducers were developed in 2 anesthetized domestic pigs using data from computerized axial thoracic tomography. Each digitized tomogram defined a unique introducer shape and was constructed using 3-dimensional (3D) modeling software and printing. Each parent pig then underwent surgery demonstrating coronary sinus lead insertion, using its custom-configured introducer. Next, with institutional review board approval, 65 patients were identified who had undergone conventional endocardial coronary sinus lead insertion followed by thoracic scanning. These tomograms were used to design appropriately curved introducers for human anatomy.

Results

Fifty-one introducer paths were defined following anatomic pathways and avoiding bends inconsistent with materials used for commercial peel-away introducers. Each path was defined by a bend and distance toward the coronary sinus ostium and a hook and twist out of plane to align with the local orientation of the coronary sinus. The average dimensions were the following: distance, 67 mm; bend angle, 47 degrees; hook angle, 39 degrees; and twist angle, 20 degrees. A prototype cannula was tested for fit in a fresh frozen postmortem human specimen.

Conclusions

Parasternal mediastinotomy access to the coronary sinus for cardiac resynchronization, mitral annuloplasty, and instrumentation is feasible. Human computerized tomographic scans can be used to define curvatures and dimensions for marketed introducers.
Transcriptional repression by PRC1 in the absence of H2A monoubiquitylation
Authors: Pengelly Ana Raquel , Kalb Reinhard , Finkl Katja , Müller Jürg
Published: July 2015

Histone H2A monoubiquitylation (H2Aub) is considered to be a key effector in transcriptional repression by Polycomb-repressive complex 1 (PRC1). We analyzed Drosophila with a point mutation in the PRC1 subunit Sce that abolishes its H2A ubiquitylase activity or with point mutations in the H2A and H2Av residues ubiquitylated by PRC1. H2Aub is essential for viability and required for efficient histone H3 Lys27 trimethylation by PRC2 early in embryogenesis. However, H2Aub-deficient animals fully maintain repression of PRC1 target genes and do not show phenotypes characteristic of Polycomb group mutants. PRC1 thus represses canonical target genes independently of H2Aub.
A signal detection theory analysis of behavioral pattern separation paradigms
Authors: Loiotile Rita E. , Courtney Susan M.
Published: July 2015

Behavioral pattern separation (BPS) paradigms ask participants to discriminate previously encoded (old) stimuli from highly similar (lure) and categorically distinct (novel) stimuli. The lure-old discrimination, thought to uniquely reflect pattern separation in the hippocampal formation, is typically pitted against the traditional novel-old discrimination. However, BPS paradigms have measured lure-old discrimination neither consistently across studies nor in such a way that allows for accurate comparison to novel-old discrimination. Therefore, we advocate for signal detection theory (SDT) as a unified framework. Moreover, we compare SDT with previously used measures of lure-old discrimination, indicating how other formulas’ inaccuracies can lead to erroneous conclusions.
Binding among select episodic elements is altered via active short-term retrieval
Authors: Bridge Donna J. , Voss Joel L.
Published: July 2015

Of the many elements that comprise an episode, are any disproportionately bound to the others? We tested whether active short-term retrieval selectively increases binding. Individual objects from multiobject displays were retrieved after brief delays. Memory was later tested for the other objects. Cueing with actively retrieved objects facilitated memory of associated objects, which was associated with unique patterns of viewing behavior during study and enhanced ERP correlates of retrieval during test, relative to other reminder cues that were not actively retrieved. Active short-term retrieval therefore enhanced binding of retrieved elements with others, thus creating powerful memory cues for entire episodes.
A two-dimensional anionic CdIIpolymer constructed through dicyanamide coordination bridges
Authors: Wang Hui-Ting , Zhou Lin , Wang Xiao-Li
Published: July 2015

In the search for potential ferroelectric materials, molecular-based one-, two- and three-dimensional cadmium(II) organic–inorganic compounds have been of interest as they often display solid–solid phase transitions induced by a variation in temperature. A new cadmium dicyanamide complex, poly[4-dimethylamino-1-ethylpyridin-1-ium [tri-μ-dicyanamido-κ6N1:N5-cadmium(II)]], {(C9H15N2)[Cd(C2N3)3]}n, was synthesized by the reaction of 4-dimethylamino-1-ethylpyridin-1-ium bromide, cadmium nitrate tetrahydrate and sodium dicyanamide in aqueous solution. In the crystal structure, each CdIIcation is octahedrally coordinated by six terminal N atoms from six anionic dicyanamide (dca) ligands. Neighbouring CdIIcations are linked together by dicyanamide bridges to form a two-dimensional coordination polymer. The organic cations are not involved in the formation of the supramolecular network.
Crystal structure of (1S,3R,8R,9R,10S)-2,4,6-tris(2,2-dichloro-3,7,7,10-tetramethyltricyclo[6.4.0.01,3]dodec-9-yl)cyclotriboroxane
Authors: Benharref Ahmed , El Ammari Lahcen , Saadi Mohamed , Mazoir Noureddine , Berraho Moha
Published: July 2015

The title compound, C48H75B3Cl6O3, was synthesized in two steps from β-himachalene (3,5,5,9-tetramethyl-2,4a,5,6,7,8-hexahydro-1H-benzocycloheptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The molecule consists of an almost planar cyclotriboroxane ring [maximum deviation = 0.036 (2) Å] linked to three identical fused ring systems with different conformations. Each of the three attached ring systems is built up from a seven-membered ring to which a six- and a three-membered ring are fused. The three six-membered rings have a twist-boat conformation, whereas the seven-membered rings display boat, chair and twist-boat conformations. The dihedral angles between the central boroxane ring and the mean planes of the attached six-membered rings are 63.67 (18), 54.89 (2) and 56.57 (19)°. The crystal packing is governed only by van der Waals interactions.
Multi-stage and multi-attribute risk group decision-making method based on grey information
Authors: Luo Dang , Li Yuwen
Published: July 2015

Purpose

– For the multi-stage and multi-attribute risk group decision-making problem, the attribute weight, decision-maker weight and time weight are unknown. The attribute value is grey information. The purpose of this paper is to discuss a decision-making method.

Design/methodology/approach

– Analysis techniques and the theory about distance degree are used to determine the decision-maker weight within single stage. Grey relational analysis method is applied to determine the attribute weight. Moreover, the uncertainty of time weight and the proximity between the attribute value and positive/negative value are taken into account. A multi-objective optimization model is established based on maximum entropy to obtain time weights, so the comprehensive value is determined.

Findings

– An example shows the effectiveness and practicability.

Originality/value

– For a decision-making process, the results are different in different periods. This method is computationally very simple, easily comprehensible.
A Fourier residual modified Nash nonlinear grey Bernoulli model for forecasting the international trade of Chinese high-tech products
Authors: Wang Zhengxin , Pei Lingling
Published: July 2015

Purpose

– Although the Nash nonlinear grey Bernoulli model (NNGBM(1, 1)) is incomparable with respect to its flexibility over traditional grey models, errors are still inevitable in forecasting. The purpose of this paper is to propose a Fourier residual modified Nash nonlinear grey Bernoulli model (FNNGBM(1, 1)) and use it to forecast the nonlinear time series of the international trade of Chinese high-tech products.

Design/methodology/approach

– A Fourier series is used to modify the forecasting residual of the NNGBM(1, 1) model, so as to improve its forecasting ability. The parameters optimization of FNNGBM(1, 1) is formulated as a combinatorial optimization problem and is solved collectively using the concept of Nash equilibrium.

Findings

– The simulation and practical application to fluctuation data both prove that FNNGBM(1, 1) could offer a more precise forecast than NNGBM(1, 1) and the Fourier residual GM(1, 1) (FGM(1, 1)). The import/export data of Chinese high-tech products will maintain rapid growth, with corresponding trade balance enlargement; however, there will be a concomitant decrease in the trade specialization coefficient.

Research limitations/implications

– This study is deliberately general in its scope and outlook: its focus is mainly on the overall condition of Chinese high-tech products trade. Future research is recommended to analyze specific industrial trade sectors and extraneous influencing factors.

Originality/value

– An effective method is proposed to enhance the accuracy of NNGBM(1, 1) model in forecasting a small sample, nonlinear time series.
Grey systems theory in economics – bibliometric analysis and applications’ overview
Authors: Camelia Delcea
Published: July 2015

Purpose

– The purpose of this paper is to synthesize the review of the existing literature attached to the grey economic system theory and applications and aims to offer a comprehensive picture of the contribution brought by the researchers to this particular field. Also, the paper underlines the main research areas within the grey economic theory and applications and serves as an informative summary kit for future research works and research directions.

Design/methodology/approach

– For appreciating the scientific progress made since the grey systems theory has been initiated to the present, with an accent on the literature dedicated to the economic field, a bibliometrics analysis has been conducted. The Perish or Publish software was used for extracting the needed data from Google Scholar for the entire period since the appearance of grey systems to now-a-days. In addition, an ISI Web of Science (WoS) search has been performed for extracting the grey economic papers. As the main focus is on the economic subject area of the grey systems, only the papers related to this field have been selected.

Findings

– The total number of grey economic paper from both Google Scholar and ISI WoS database, the number of authors, some citation metrics, H-index, authors’ provenience country, papers’ language, etc., have been presented and analysed. Also, a list with the most cited papers in the grey economic relational analysis, grey economic prediction models and grey economic incidence is putted forward.

Practical implications

– Through the bibliometric analysis on grey economic papers written over time, a qualitative analysis was performed on this field in order to underline the main research direction, to analyse what has been done in this field and to determine which can be the next research directions that can emerge from here.

Originality/value

– The paper succeeds in enlarging the view regarding the usage of grey systems theory in the economic field, offering a suitable analysis on the considered areas. Even though bibliometrics analysis have been conducted on the grey systems theory field, a grey economic bibliometric analysis has not been done yet, to the authors’ knowledge. Therefore, a synthesized of the existing literature attached to the grey economic system theory and applications is presented in order to offer a more comprehensive picture of the contribution brought by the researchers to this particular field.
An analysis of intermediate inputs influencing the gross products of agriculture and its composition based on grey incidence analysis
Authors: Zhan Huibin , Liu Sifeng
Published: July 2015

Purpose

– Taking Huangshan City as an example, the purpose of this paper is to explore the relationship between gross products of agriculture (GPA), its main composition as well as their influential intermediate inputs, followed by some suggestion, in order to optimize agricultural industrial structure and distribute the ratio of various inputs in agriculture, farming, forestry, animal husbandry and fishery, so as to improve GPA of Huangshan City.

Design/methodology/approach

– This paper is characterized by an exploratory research by using the grey incidence analysis based on the grey systems theory initiated by Chinese professor Julong Deng. The original data processed in the model are quoted from the Statistical Yearbook of Huangshan City.

Findings

– This paper draws some important conclusions. First, in terms of large, intermediate inputs in animal husbandry production and fishery production are two important aspects which affect the growth potentiality of agricultural gross products in Huangshan City. This also reflects that the development potentialities of fishery and animal husbandry are larger. Second, the level of agricultural modernization is relatively low in Huangshan City, the growth of agricultural output relies on a large number of inputs such as fertilizers, pesticides, but it also reflects the agriculture production system has huge potentiality to increase in Huangshan City from the side. Third, agriculture producer services as a whole is still relatively weak in Huangshan City. It is difficult to adapt to the development of modern agriculture and agricultural modernization. Finally, the results show that intermediate inputs have different influence on farming, forestry, animal husbandry and fishery.

Originality/value

– Suggestion are also proposed to the related policy makers as follows: to vigorously develop animal husbandry and fishery in order to optimize agricultural industrial structure of Huangshan City, to improve agricultural modernization level, to speed up the service support system construction of agriculture production, to optimize the allocation of inputs in farming, forestry, animal husbandry and fishery reasonably.
Grey system based novel approach for stock market forecasting
Authors: Rathnayaka R.M. Kapila Tharanga , Seneviratna D.M.K.N , Jianguo Wei
Published: July 2015

Purpose

– Making decisions in finance have been regarded as one of the biggest challenges in the modern economy today; especially, analysing and forecasting unstable data patterns with limited sample observations under the numerous economic policies and reforms. The purpose of this paper is to propose suitable forecasting approach based on grey methods in short-term predictions.

Design/methodology/approach

– High volatile fluctuations with instability patterns are the common phenomenon in the Colombo Stock Exchange (CSE), Sri Lanka. As a subset of the literature, very few studies have been focused to find the short-term forecastings in CSE. So, the current study mainly attempted to understand the trends and suitable forecasting model in order to predict the future behaviours in CSE during the period from October 2014 to March 2015. As a result of non-stationary behavioural patterns over the period of time, the grey operational models namely GM(1,1), GM(2,1), grey Verhulst and non-linear grey Bernoulli model were used as a comparison purpose.

Findings

– The results disclosed that, grey prediction models generate smaller forecasting errors than traditional time series approach for limited data forecastings.

Practical implications

– Finally, the authors strongly believed that, it could be better to use the improved grey hybrid methodology algorithms in real world model approaches.

Originality/value

– However, for the large sample of data forecasting under the normality assumptions, the traditional time series methodologies are more suitable than grey methodologies; especially GM(1,1) give some dramatically unsuccessful results than auto regressive intergrated moving average in model pre-post stage.
The hybrid intelligent systems design using grey systems theory
Authors: Emil Scarlat , Mărăcine Virginia
Published: July 2015

Purpose

– The purpose of this paper is to discuss how tacit and explicit knowledge determine grey knowledge and how these are stimulated through interactions within networks, forming the grey hybrid intelligent systems (HISs). The feedback processes and mechanisms between internal and external knowledge determine the apparition of grey knowledge into an intelligent system (IS). The extension of ISs is determined by the ubiquity of the internet but, in our framework, the grey knowledge flows assure the viability and effectiveness of these systems.

Design/methodology/approach

– Some characteristics of the Hybrid Intelligent Knowledge Systems are put forward along with a series of models of hybrid computational intelligence architectures. More, relevant examples from the literature related to the hybrid systems architectures are presented, underlying their main advantages and disadvantages.

Findings

– Due to the lack of a common framework it remains often difficult to compare the various HISs conceptually and evaluate their performance comparatively. Different applications in different areas are needed for establishing the best combinations between models that are designed using grey, fuzzy, neural network, genetic, evolutionist and other methods. But all these systems are knowledge dependent, the main flow that is used in all parts of every kind of system being the knowledge. Grey knowledge is an important part of the real systems and the study of its proprieties using the methods and techniques of grey system theory remains an important direction of the researches.

Originality/value

– The paper discusses the differences among the three types of knowledge and how they and the grey systems theory can be used in different hybrid architectures.
Grey incidence between KPIs and hospital performance
Authors: Bradea Ioana , Mărăcine Virginia
Published: July 2015

Purpose

– Performance indicates how well the activities, operations and business processes of an enterprise are performed. In health care, performance illustrates the quality of medical services and targets the strategic objectives, the efficiency and effectiveness and the obtaining of the desired financial results. In economic analysis, the key performance indicators (KPIs) offers real, relevant and accurate information regarding the performance, using analysis and diagnosis techniques. The purpose of this paper is to discuss grey systems theory in order to bridge the KPIs and the hospital’s performance.

Design/methodology/approach

– Using the grey systems theory, the impact of seven selected KPIs (the beds utilization rate, the average length of hospitalization, the average cost of hospitalization/day, the proportion of physicians in total staff, the nosocomial infection rate, the death rate and the diagnostic concordance) on the hospital’s turnover is determined.

Findings

– By analyzing the grey incidence between turnover and several KPIs, for a period of six years, it has been concluded that the greatest impact on performance has the diagnostic concordance and the percent of the physicians in the total staff, followed by the nosocomial infection rate, the average bed utilization rate and the death rate.

Research limitations/implications

– The considered case study should be extended by including a greater number of hospitals into the analysis.

Originality/value

– The usage of the grey systems theory in an uncertain and limited information field such as the medical one, is a premier in this field. According to the grey incidence analysis results, the performance of health care institutions depends mainly on the quality of medical staff (that influence the diagnostic concordance, the nosocomial infection rate and the death rate) and on the management ability to attract competent and well-trained physicians, which can conduct in a new approach that should be considered by the hospitals’ managerial staff.
Where are the Europeans? A longitudinal analysis of the world’s largest TMT companies
Authors: Curwen Peter , Sadowski Bert , Whalley Jason
Published: July 2015

Purpose

– This paper aims to identify the number of European companies among the world’s largest telecommunication, media and technology (TMT) companies. Through this, industry trends will be discerned and light shed on whether European companies are losing out to their rivals based in the USA and Asia in relation to the new highly technological economy that is emerging.

Design/methodology/approach

– The paper begins by outlining the context for the study before detailing the data sources used in the analysis of the world’s largest TMT companies. The data are drawn from successive annual lists of the world’s largest companies published by theFinancial Times.

Findings

– The paper highlights the limited European presence among the world’s largest TMT companies. A significant proportion of these companies provide telecommunication services.

Research limitations/implications

– The paper draws on annual lists compiled by theFinancial Times. The categorisation adopted in these lists changes over time and does not facilitate the identification of TMT operations in companies where the main activities are in other sectors.

Practical implications

– There is a need for more data to be available in the public domain. One aspect of this relates to the need to extend the analysis to include smaller TMT companies, while another is the need for more detailed information regarding companies operating in more than one sector.

Originality/value

– The paper extends existing research into structural change within the TMT sector by focussing on Europe. A longitudinal approach is adopted, with the companies uniquely divided into six lines of business.
An acceptance model for smart watches
Authors: Kim Ki Joon , Shin Dong-Hee
Published: July 2015

Purpose

– The purpose of this paper is to identify the key psychological determinants of smart watch adoption (i.e. affective quality (AQ), relative advantage (RA), mobility (MB), availability (AV), subcultural appeal) and develops an extended technology acceptance model (TAM) that integrates the findings into the original TAM constructs.

Design/methodology/approach

– An online survey assessed the proposed psychological determinants of smart watch adoption. Confirmatory factor analysis (CFA) and structural equation modeling (SEM) were conducted on collected data (n=363) using the AMOS 22 statistical software. The reliability and validity of the measurement assessing the proposed factor structure were examined via CFA, while the strength and direction of the hypothesized causal paths among the constructs were analyzed via SEM.

Findings

– The AQ and RA of smart watches were found to be associated with perceived usefulness, while the sense of MB and AV induced by smart watches led to a greater perceived ease of the technology’s use. The results also indicated that the devices’ subcultural appeal and cost were notable antecedents of user attitude (AT) and intention to use, respectively.

Originality/value

– Though smart watches are becoming increasingly popular, empirical studies on user perceptions of and ATs toward – them remain preliminary. This paper is one of the first scholarly attempts at a systematic prediction of smart watch usage, with implications for the adoption of future wearable technology.