bluuebunny/crossref_metadata_2025 huggingface dataset:
Joint Raman spectroscopic and quantum chemical analysis of the vibrational features of Cs2RuO4
Authors: Naji M. , Di Lemma F. , Kovács A. , Beneš O. , Manara D. , Colle J.‐Y. , Pagliosa G. , Raison P. , Konings R. J. M.
Published: April 2015

The Raman spectroscopic characterization of the orthorhombic phase of Cs2RuO4 was carried out by means of group theory and quantum chemical analysis. Multiple models based on ruthenate (VI+) tetrahedra were tested, and characterization of all the active Raman modes was achieved. A comparison of Raman spectra of Cs2RuO4, Cs2MoO4, and Cs2WO4 was also performed. Raman laser heating induced a phase transition from an ordered to a disordered structure. The temperature‐phase transition was calculated from the anti‐Stokes/Stokes ratio and compared with the ones measured at macroscopic scale. The phase transition is connected with tilting and/or rotations of RuO4 tetrahedra, which lead to a disorder at the RuO4 sites. © 2015 The Authors. Journal of Raman Spectroscopy published by John Wiley & Sons Ltd.
Polymer Interphase Self‐Reinforcement and Strengthening Mechanisms in Low‐Loaded Nanocomposite Fibers
Authors: Song Kenan , Zhang Yiying , Minus Marilyn L.
Published: April 2015

The effect of filler concentration on understanding structure–property relationships in polymer composites with low nanocarbon (nC) loadings (<1 wt%) is investigated. The presence of the carbon nanochips (CNC) filler induces the formation of highly ordered self‐reinforcing interphase regions within the composite fibers. The influence of these regions on the structure and properties of the fibers is analyzed by both theoretical and experimental methods. Analysis of the filled polyvinyl alcohol (PVA) fibers demonstrates that the presence of the nC influences the organization and formation of crystalline and amorphous polymer lamellae stacking in the fibers, leading to variations in grain structure for the composites. These structural developments contribute specifically to the property increases (i.e., elastic modulus increased by 222% and tensile strength increased by 186%) for the PVA/CNC composites in comparison to control PVA fibers.

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A compact orthogonal wideband printed mimo antenna for WiFi/WLAN/LTE applications
Authors: Marzudi W. N. N. W. , Abidin Z. Z. , Dahlan S. H. , Yue Ma , Abd‐Alhameed Raed A. , Child M. B.
Published: April 2015

This article presents a wideband multiple‐input‐multiple‐output (MIMO) antenna assembly for combined WiFi/WLAN/LTE applications. The antenna consists of two radiating triangular patches placed in a mutually orthogonal configuration. Two T‐slots and a rectangular slot were cut on the ground plane to improve the return loss and isolation. The surface footprint of the antenna is 30 × 30 mm2. The antenna impedance bandwidth is 101.7% between 2280 and 7000 MHz; the reflection coefficient and mutual coupling are better than −10 dB, and −14 dB, respectively. The MIMO antenna performance characteristics are given in terms of the scattering parameters, envelope correlation coefficient, total active reflection coefficient, capacity loss, channel capacity, VSWR, antenna gain and radiation patterns. Analysis of these characteristics indicates that the design is appropriate for the target WiFi/WLAN/LTE terminal applications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1733–1738, 2015
Circularly polarized bowtie‐shaped dielectric resonator antenna excited with asymmetric cross slot
Authors: Chauthaiwale Prachi , Chaudhary Raghvendra Kumar , Srivastava Kumar Vaibhav
Published: April 2015

A circularly polarized bowtie‐shaped dielectric resonator antenna (DRA) excited by an asymmetric cross‐shaped slot, fed by a microstrip line has been proposed in this article. The proposed antenna structure achieves a 3‐dB axial ratio bandwidth of 7.4%. An impedance bandwidth of 43.8% has been obtained for circularly polarized bowtie‐shaped DRA. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1723–1727, 2015
An efficient approach to generate microwave vector‐vortex fields based on metasurface
Authors: Tan Yunhua , Li Lianlin , Ruan Henxin
Published: April 2015

This study presents a simple but efficient approach to generate microwave vector‐vortex beams based on the metasurface composed of quasi‐periodic aperture‐coupled patch elements. We demonstrate that the vector‐vortex field with or without spiral phase can be achieved by changing the polarization of incident wave. Moreover, the spiral phase and/or polarization angle of produced vector‐vortex beams can be manipulated by tuning the topological charge τ. Results obtained using the commercial software CST Microwave Studio 2012 are presented to verify our methodology. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1708–1713, 2015
3.6‐GHz 10‐antenna array for mimo operation in the smartphone
Authors: Wong Kin‐Lu , Lu Jun‐Yu
Published: April 2015

A 10‐antenna array operating in the 3.6‐GHz band (3400–3800 MHz) for multi‐input multi‐output (MIMO) operation in the smartphone is presented. Each antenna in the proposed array is a microstripline‐fed open‐slot antenna with same small dimensions of 3 × 8 mm2 (0.036λ × 0.096λ, λ is the wavelength at 3.6 GHz). The proposed array consists of two symmetric five‐antenna arrays disposed, respectively, along two long side edges of the system ground plane of the smartphone. The proposed array is expected to be placed in the narrow spacing between the display panel and the long side edges of the smartphone. Acceptable isolation (better than about 10 dB) and good envelop correlation coefficient (ECC) of less than 0.1 for any two antennas in the proposed array is obtained. The maximum channel capacity of the proposed array in a 10 × 10 MIMO system is calculated to reach about 47 bps/Hz at 20‐dB signal‐to‐noise ratio, which is larger than four times that (11.5 bps/Hz) of the upper limit of an ideal 2 × 2 MIMO system with 100% antenna efficiency and zero ECC between antennas. Details of the proposed 10‐antenna array are described, and the experimental results are presented and discussed. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1699–1704, 2015
1.1 GBIT/S white lighting LED‐based visible light link with pulse amplitude modulation and Volterra DFE equalization
Authors: Stepniak Grzegorz , Maksymiuk Lukasz , Siuzdak Jerzy
Published: April 2015

We report a visible light communication link that uses a white phosphorescent LED as transmitter and a p‐i‐n photodiode combined with blue optical filter as a receiver. Multilevel pulse amplitude modulation (PAM) is used for data transmission. It is shown that a receiver with a decision feedback equalizer and nonlinear second‐order Volterra feed‐forward section allows for 1.1 Gbit/s throughput at BER = 10–3 when used with PAM‐4. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1620–1622, 2015
Comparison of the repeatability of GABA‐edited magnetic resonance spectroscopy with and without macromolecule suppression
Authors: Mikkelsen Mark , Singh Krish D. , Sumner Petroc , Evans C. John
Published: April 2015

Purpose

The inhibitory neurotransmitter γ‐aminobutyric acid (GABA) can be measured in vivo using edited magnetic resonance spectroscopy (MRS), but quantification suffers from contamination by macromolecules (MM). It is possible to suppress this contamination using symmetric editing, but this procedure potentially compromises reliability of the GABA measurement. The aim of this study was to compare the repeatability of GABA‐edited MRS with and without MM suppression.

Methods

GABA′ (non‐MM contaminated) and GABA′+MM (MM‐contaminated) concentration was measured in the occipital lobe (OCC) and anterior cingulate (AC) using symmetric and standard editing (n = 15). Each method was performed twice in each region.

Results

Within‐participant coefficients of variation for each technique were 4.0% (GABA′+MM) and 8.6% (GABA′) in the OCC and 14.8% (GABA′+MM) and 12.6% (GABA′) in the AC. Intraclass correlation coefficients were better for the suppression method than standard editing in both the OCC (0.72 versus 0.67) and AC (0.41 versus 0.16). These findings were replicated in the OCC of a second cohort (n = 15).

Conclusion

Symmetric suppression is shown to be comparable in repeatability to standard GABA‐editing. Measuring a purer quantification of GABA becomes increasingly important as more research is conducted on links between GABA concentration, pathology and healthy behavior. Magn Reson Med 75:946–953, 2016. © 2015 Wiley Periodicals, Inc.
Interventions targeting absences increase adherence and reduce abandonment of childhood cancer treatment in El Salvador
Authors: Salaverria Carmen , Rossell Nuria , Hernandez Angelica , Fuentes Alabi Soad , Vasquez Roberto , Bonilla Miguel , Lam Catherine G. , Ribeiro Raul C.
Published: April 2015

Background

In El Salvador, about 200 new cases of pediatric cancer are diagnosed each year, and survival rates approach 70%. Although treatment is available at no cost, abandonment of therapy has remained at a steady yearly rate of 13% during the past decade. A time sensitive adherence tracking procedure (TS‐ATP) was recently implemented to detect missed appointments, identify their causes, and intervene promptly.

Procedure The study team was informed daily of patient/family failure to attend medical appointments in the pediatric oncology unit; the families were contacted and interviewed to ascertain and address the reasons. Patients who did not return after this initial contact were contacted again through local health clinics and municipalities. Law enforcement was a last resort for patients undergoing frontline treatment with a good prognosis., The system was adapted to clinical urgency: families of patients undergoing induction therapy were contacted within 24 hr, those in other therapy phases, within 48 hr, and those who had completed treatment, within one week. Reasons for absence were obtained by telephone or in person.

Results

The annual rate of abandonment was reduced from 13–3% during the 2 years period. There were 1,111 absences reported and 1,472 contacts with caregivers and institutions. The three main reasons for absences were financial needs (165, 23%), unforeseen barriers (116, 16%), and domestic needs (86, 12%).

Conclusions

Use of the treatment adherence tracking system to locate and communicate with patients/families after missed appointments and the allocated aid stemming from these interviews substantially reduced abandonment and non‐adherence. Pediatr Blood Cancer 2015;62:1609–1615. © 2015 Wiley Periodicals, Inc.
Relating gas phase to solution conformations: Lessons from disordered proteins
Authors: Beveridge Rebecca , Phillips Ashley S. , Denbigh Laetitia , Saleem Hassan M. , MacPhee Cait E. , Barran Perdita E.
Published: April 2015

In recent years both mass spectrometry (MS) and ion mobility mass spectrometry (IM‐MS) have been developed as techniques with which to study proteins that lack a fixed tertiary structure but may contain regions that form secondary structure elements transiently, namely intrinsically disordered proteins (IDPs). IM‐MS is a suitable method for the study of IDPs which provides an insight to conformations that are present in solution, potentially enabling the analysis of lowly populated structural forms. Here, we describe the IM‐MS data of two IDPs; α‐Synuclein (α‐Syn) which is implicated in Parkinson's disease, and Apolipoprotein C‐II (ApoC‐II) which is involved in cardiovascular diseases. We report an apparent discrepancy in the way that ApoC‐II behaves in the gas phase. While most IDPs, including α‐Syn, present in many charge states and a wide range of rotationally averaged collision cross sections (CCSs), ApoC‐II presents in just four charge states and a very narrow range of CCSs, independent of solution conditions. Here, we compare MS and IM‐MS data of both proteins, and rationalise the differences between the proteins in terms of different ionisation processes which they may adhere to.
Developmental roles of protein N‐terminal acetylation
Authors: Silva Rui D. , Martinho Rui G.
Published: April 2015

Discovered more than 50 years ago, N‐terminal acetylation (N‐Ac) is one of the most common protein modifications. Catalyzed by different N‐terminal acetyltransferases (NATs), N‐Ac was originally believed to mostly promote protein stability. However, several functional consequences at substrate level were recently described that yielded important new insights about the distinct molecular functions for this modification. The ubiquitous and apparent irreversible nature of this protein modification leads to the assumption that N‐Ac mostly executes constitutive functions. In spite of the large number of substrates for each NAT, recent studies in multicellular organisms have nevertheless indicated very specific phenotypes after NAT loss. This raises the hypothesis that in vivo N‐Ac is only functionally rate limiting for a small subset of substrates. In this review, we will discuss the function of N‐Ac in the context of a developing organism. We will propose that some rate limiting NAT substrates may be tissue‐specific leading to differential functions of N‐Ac during development of multicellular organisms. Moreover, we will also propose the existence of tissue and developmental‐specific mechanisms that differentially regulate N‐Ac.
Electron transmission through step‐like potential in armchair and zigzag graphene nanoribbons: Comparison of different interfaces
Authors: Onipko Alexander , Malysheva Lyuba
Published: April 2015

We present the one‐electron spectrum and eigenstates of bounded graphene nanoribbons that describe electron dynamics in terms of transverse and longitudinal motion. On this basis, we find the transmission coefficients for armchair graphene nanoribbons and polyacene under step‐like electronic potential. The problem is solved for different interfaces between the regions with zero and nonzero site energies. The obtained results have numerous applications to the construction of multi‐terminal graphene‐based electronic devices.
Spectral dependence of light extraction efficiency of high‐power III‐nitride light‐emitting diodes
Authors: Karpov Sergey Yu. , Binder Michael , Galler Bastian , Schiavon Dario
Published: April 2015

Using the recently suggested method of processing the data on external quantum efficiency as a function of output optical power, we have estimated the dependence of light extraction efficiency of high‐power light‐emitting diodes (LEDs) on their emission wavelength varied between 425 nm and 540 nm. The extraction efficiency is found to increase with the wavelength from ∼80% to ∼85% in this spectral range and to correlate with the wavelength dependence of reflectivity of the large‐area p‐electrode being the essential unit of the LED chip design. The correlation found identifies the incomplete reflection of emitted light from the electrode as the major mechanism eventually controlling the spectral dependence of the efficiency of light extraction from the LEDs.

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Spectral dependence of light extraction efficiency of the UX:3TM LED chip: comparison of experiment and modelling results.

(© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
Theoretical prediction of the optical rotation of chiral molecules in ordered media: A computational study of (Ra)‐1,3‐dimethylallene, (2R)‐2‐methyloxirane, and (2R)‐N‐methyloxaziridine
Authors: Caputo Maria C. , Pelloni Stefano , Lazzeretti Paolo
Published: April 2015

A theoretical procedure has been developed and implemented to calculate the optical rotation of chiral molecules in ordered phase via origin‐independent diagonal components
,
of the optical activity tensor and origin‐independent components
, for
, of the mixed electric dipole‐electric quadrupole polarizability. Origin independence was achieved by referring these tensors to the principal axis system of the electric dipole dynamic polarizability
at the same laser frequency ω. The approach has been applied, allowing for alternative quantum mechanical methods based on different gauges, to estimate near Hartree–Fock values for three chiral molecules, (2R)‐N‐methyloxaziridine C2NOH5, (2R)‐2‐methyloxirane (also referred to as propylene oxide) C3OH6, and (
)‐1,3‐dimethylallene C5H8, at two frequencies. The theoretical predictions can be useful for an attempt at measuring correspondent experimental values in crystal phase. © 2015 Wiley Periodicals, Inc.
A Classification of Stream Water Temperature Regimes in the Conterminous USA
Authors: Maheu A. , Poff N. L. , St‐Hilaire A.
Published: April 2015

Temporal variability in water temperature plays an important role in aquatic ecosystems, yet the thermal regime of streams has mainly been described in terms of mean or extreme conditions. In this study, annual and diel variability in stream water temperature was described at 135 unregulated, gauged streams across the USA. Based on magnitude, amplitude and timing characteristics of daily water temperature records ranging from 5 to 33 years, we classified thermal regimes into six distinct types. This classification underlined the importance of including characteristics of variability (amplitude and timing) in addition to aspects of magnitude to discriminate thermal regimes at the continental scale. We used a classification tree to predict thermal regime membership of the six classes and found that the annual mean and range in the long‐term air temperature average along with spring flows were important variables defining the thermal regime types at the continental scale. This research provides a framework for a comprehensive characterization of the thermal regimes of streams that could provide a basis for future assessment of changes in water temperature caused by anthropogenic activities such as dams, land use changes and climate change. Copyright © 2015 John Wiley & Sons, Ltd.
A Finite Mixture of Nonlinear Random Coefficient Models for Continuous Repeated Measures Data
Authors: Kohli Nidhi , Harring Jeffrey R. , Zopluoglu Cengiz
Published: April 2015

Nonlinear random coefficient models (NRCMs) for continuous longitudinal data are often used for examining individual behaviors that display nonlinear patterns of development (or growth) over time in measured variables. As an extension of this model, this study considers the finite mixture of NRCMs that combine features of NRCMs with the idea of finite mixture (or latent class) models. The efficacy of this model is that it allows the integration of intrinsically nonlinear functions where the data come from a mixture of two or more unobserved subpopulations, thus allowing the simultaneous investigation of intra-individual (within-person) variability, inter-individual (between-person) variability, and subpopulation heterogeneity. Effectiveness of this model to work under real data analytic conditions was examined by executing a Monte Carlo simulation study. The simulation study was carried out using an R routine specifically developed for the purpose of this study. The R routine used maximum likelihood with the expectation–maximization algorithm. The design of the study mimicked the output obtained from running a two-class mixture model on task completion data.
The Use of a Single Volar Locking Plate for AO C3-Type Distal Radius Fractures
Authors: Earp Brandon E. , Foster Brian , Blazar Philip E.
Published: April 2015

Background

A single volar locking plate (VLP) is now frequently used for open reduction and internal fixation (ORIF) of many types of distal radius fractures. Comminuted intra-articular distal radius fractures (AO C3-type) are typically the most challenging to surgically treat. No studies directly address the adequacy of a VLP alone for maintaining reduction of AO C-type fractures. We hypothesized that a single VLP provides an effective method for maintaining reduction for these fractures.

Methods

We retrospectively evaluated radiographs of a series of AO C-type fractures. Seventy-seven patients with 77 AO C3-type fractures were identified from billing records and were eligible for the study. All patients were treated by fellowship-trained hand surgeons. Radiographs at the time of union were compared to those from immediately postoperatively.

Results

Sixty-nine of 77 (89.6 %) fractures treated with VLP fixation alone for AO C3-type distal radius fractures united without loss of reduction. Eight of 77 (10.4 %) patients treated with VLP for AO C3 fractures lost reduction. The most common fracture fragment to lose reduction was the lunate fossa (5 of 8); loss of reduction of the scaphoid fossa die-punch fragment (2 of 8) and the radial styloid (1 of 8) were also seen.

Conclusions

The majority (89.6 %) of AO C3-type fractures treated with a single volar locking plate come to union without loss of reduction. Level of evidence: Level IV.
The Relationship Between Microstructural Evolution and Mechanical Properties of Heavy Plate of Low-Mn Steel During Ultra Fast Cooling
Authors: Wang Bin , Wang Zhao-dong , Wang Bing-xing , Wang Guo-dong , Misra R. D. K.
Published: April 2015

We describe here the electron microscopy and mechanical property studies that were conducted in an industrially processed 20- and 40-mm C-Mn thick plates that involved a new approach of ultrafast cooling (UFC) together with significant reduction in Mn-content of the steel by ~0.3 to 0.5 pct, in relation to the conventional C-Mn steels, with the aim of cost-effectiveness. The study demonstrated that nanoscale cementite precipitation occurred during austenite transformation in the matrix of heavy plate during UFC, providing significant precipitation strengthening. With decrease in UFC stop temperature and consequent increase in the degree of undercooling, there was a transition in the morphology of cementite from lamellar to irregular-shaped nanoscale particles in the 20 mm heavy plate. With the increase in plate thickness, nanoscale cementite precipitated in bainitic lath at the surface of 40 mm heavy plate, which significantly increased the strength and decreased the elongation. Simultaneously, microstructural evolution in hot-rolled sheets was studied via simulation experiments using laboratory rolling mill to define the limits of microstructural evolution that can obtained in the UFC process and develop an understanding of the evolved microstructure in terms of process parameters.
Targeting histone deacetylase 6 mediates a dual anti‐melanoma effect: Enhanced antitumor immunity and impaired cell proliferation
Authors: Woan K.V. , Lienlaf M. , Perez-Villaroel P. , Lee C. , Cheng F. , Knox T. , Woods D.M. , Barrios K. , Powers J. , Sahakian E. , Wang H.W. , Canales J. , Marante D. , Smalley K.S.M. , Bergman J. , Seto E. , Kozikowski A. , Pinilla-Ibarz J. , Sarnaik A. , Celis E. , Weber J. , Sotomayor E.M. , Villagra A.
Published: April 2015

The median survival for metastatic melanoma is in the realm of 8–16 months and there are few therapies that offer significant improvement in overall survival. One of the recent advances in cancer treatment focuses on epigenetic modifiers to alter the survivability and immunogenicity of cancer cells. Our group and others have previously demonstrated that pan‐HDAC inhibitors induce apoptosis, cell cycle arrest and changes in the immunogenicity of melanoma cells. Here we interrogated specific HDACs which may be responsible for this effect. We found that both genetic abrogation and pharmacologic inhibition of HDAC6 decreases in vitro proliferation and induces G1 arrest of melanoma cell lines without inducing apoptosis. Moreover, targeting this molecule led to an important upregulation in the expression of tumor associated antigens and MHC class I, suggesting a potential improvement in the immunogenicity of these cells. Of note, this anti‐melanoma activity was operative regardless of mutational status of the cells. These effects translated into a pronounced delay of in vivo melanoma tumor growth which was, at least in part, dependent on intact immunity as evidenced by the restoration of tumor growth after CD4+ and CD8+ depletion. Given our findings, we provide the initial rationale for the further development of selective HDAC6 inhibitors as potential therapeutic anti‐melanoma agents.
Political Ties of Listed Chinese Companies, Performance Effects, and Moderating Institutional Factors
Authors: Arnoldi Jakob , Villadsen Anders R.
Published: April 2015

Although development in China is quite heterogeneous across regions, little research has explored how the value of Chinese firms’ political ties is contingent on the institutional and economic development of firms’ regional environment. This article explores some of the factors that moderate the benefit of political ties, differentiating between ties to central and local government. The study investigates how benefits of ties to central and local government are moderated by regional market and economic development, respectively. The study is based on a quantitative analysis of 858 listed Chinese firms. The results suggest that firms enjoy a positive effect of political ties but mainly ties to central government. The analysis, furthermore, finds these ties to be less valuable in economically well-developed regions. Market development, on the other hand, does not moderate the effects of local or central government ties.
SHAPIRO’S UNCERTAINTY PRINCIPLE IN THE DUNKL SETTING
Authors: GHOBBER SAIFALLAH
Published: April 2015

The Dunkl transform ${\mathcal{F}}_{k}$ is a generalisation of the usual Fourier transform to an integral transform invariant under a finite reflection group. The goal of this paper is to prove a strong uncertainty principle for orthonormal bases in the Dunkl setting which states that the product of generalised dispersions cannot be bounded for an orthonormal basis. Moreover, we obtain a quantitative version of Shapiro’s uncertainty principle on the time–frequency concentration of orthonormal sequences and show, in particular, that if the elements of an orthonormal sequence and their Dunkl transforms have uniformly bounded dispersions then the sequence is finite.
Neue Westpolitik: The Clandestine Campaign to Westernize the SPD in Cold War Berlin, 1948–1958
Authors: Krause Scott H.
Published: April 2015

This article focuses on the joint campaign of “remigrés” and American authorities to “westernize” the local Social Democratic Party (SPD) in Berlin during the early Cold War. The years 1948 to 1958 witnessed one of postwar Germany's most bitter intraparty struggles for leadership within the Berlin SPD, where a faction of remigrés led by Ernst Reuter and Willy Brandt wrestled for control with the so-calledKeulenriegearound Franz Neumann. Examining clandestine American support for the remigré faction, which included favorable media coverage and considerable financial contributions, this article focuses in particular on the political maneuvering of a German-American network around Shepard Stone, political advisor to U.S. Commissioner John McCloy. An investigation of the postwar power struggle within the Berlin SPD offers fresh perspectives on three related subjects: the role of remigrés in postwar Germany history; the political clout of informal German-American networks; and West Berlin as an alternative laboratory of German democratization.
Ball lightning with the nonrelativistic electrons of the core
Authors: Shmatov M. L.
Published: April 2015

The lifetimes, volume densities of energy, electron and ion densities and other parameters of ball lightning cores with the nonrelativistic electrons are estimated. The model according to which the motion of the electrons of the ball lightning core is the superposition of the oscillatory motion and the thermal motion in the directions perpendicular to those of the oscillations is proposed. Some problems related to isolation of the ball lightning core from the atmosphere and the transfer of the atmospheric pressure on it are considered.
Intermittency and random matrices
Authors: Sokoloff Dmitry , Illarionov E. A.
Published: April 2015

A spectacular phenomenon of intermittency, i.e. a progressive growth of higher statistical moments of a physical field excited by an instability in a random medium, attracted the attention of Zeldovich in the last years of his life. At that time, the mathematical aspects underlying the physical description of this phenomenon were still under development and relations between various findings in the field remained obscure. Contemporary results from the theory of the product of independent random matrices (the Furstenberg theory) allowed the elaboration of the phenomenon of intermittency in a systematic way. We consider applications of the Furstenberg theory to some problems in cosmology and dynamo theory.
Diagnostics of peak laser intensity based on the measurement of energy of electrons emitted from laser focal region
Authors: Kalashnikov M. , Andreev A. , Ivanov K. , Galkin A. , Korobkin V. , Romanovsky M. , Shiryaev O. , Schnuerer M. , Braenzel J. , Trofimov V.
Published: April 2015

A new method to determine the peak intensity of focused relativistic laser pulses is experimentally justified. It is based on the measurement of spectra of electrons, accelerated in the beam waist. The detected electrons were emitted from the plasma, generated by nonlinear ionization of low-density gases (helium, argon, and krypton) in the focal area of a laser beam with the peak intensity >1020 W/cm2. The measurements revealed generation of particles with the maximum energy of a few MeV, observed at a small angle relative to the beam axis. The results are supported by numerical particle-in-cell simulations of a laser–low-density plasma interaction. The peak intensity in the focal region derived from experimental data reaches the value of 2.5 × 1020 W/cm2.
Path Planning and scheduling for a fleet of autonomous vehicles
Authors: Xidias Elias , Zacharia Paraskevi , Nearchou Andreas
Published: April 2015

This paper presents a new solution approach for managing the motion of a fleet of autonomous vehicles (AVs) in indoor factory environments. AVs are requested to serve a number of workstations (WS) (following a specified desired production plan for materials requirements) while taking into account the safe movement (collisions avoidance) in the shop floor as well as time duration and energy resources. The proposed approach is based on the Bump-Surface concept to represent the 2D environment through a single mathematical entity. The solution of the combined problem of path planning and task scheduling is searched on a higher-dimension B-surface (in our case 3D) in such a way that its inverse image into the robot environment satisfies the given objectives and constraints. Then, a modified Genetic Algorithm (GA) is used to search for a near-optimum solution. The objective of the fleet coordination consists of determining the best feasible paths for the AVs so that all the WS are served at the lowest possible cost. The efficiency of the developed method is investigated and discussed through characteristic simulated experiments concerning a variety of operating environments.
Dual arm-angle parameterisation and its applications for analytical inverse kinematics of redundant manipulators
Authors: Xu Wenfu , Yan Lei , Mu Zonggao , Wang Zhiying
Published: April 2015

An S-R-S (Spherical-Revolute-Spherical) redundant manipulator is similar to a human arm and is often used to perform dexterous tasks. To solve the inverse kinematics analytically, the arm-angle was usually used to parameterise the self-motion. However, the previous studies have had shortcomings; some methods cannot avoid algorithm singularity and some are unsuitable for configuration control because they use a temporary reference plane. In this paper, we propose a method of analytical inverse kinematics resolution based on dual arm-angle parameterisation. By making use of two orthogonal vectors to define two absolute reference planes, we obtain two arm angles that satisfy a specific condition. The algorithm singularity problem is avoided because there is always at least one arm angle to represent the redundancy. The dual arm angle method overcomes the shortcomings of traditional methods and retains the advantages of the arm angle. Another contribution of this paper is the derivation of the absolute reference attitude matrix, which is the key to the resolution of analytical inverse kinematics but has not been previously addressed. The simulation results for typical cases that include the algorithm singularity condition verified our method.
Consumers' perception-oriented product form design using multiple regression analysis and backpropagation neural network
Authors: Chen Hung-Yuan , Chang Hua-Cheng
Published: April 2015

Consumers' psychological perceptions of a product are significantly influenced by its appearance aesthetics, and thus product form plays an essential role in determining the commercial success of a product. The evolution of a product's form during the design process is typically governed by the designer's individual preferences and creative instincts. As a consequence, there is a risk that the product form may fail to satisfy the consumers' expectations or may induce an unanticipated consumer response. This study commences developing an integrated design approach based on the numerical definition of product form. A series of evaluation trials are then performed to establish the correlation between the product form features and the consumers' perceptions of the product image. The results of the evaluation trials are used to construct three different types of mathematical model (a multiple regression analysis model, a backpropagation neural network model, and a multiple regression analysis with a backpropagation neural network model) to predict the likely consumer response to any arbitrary product form. The feasibility of an integrated design approach is demonstrated using a three-dimensional knife form. Although this study takes an example for illustration and verification purposes, the methodology proposed in the present study is equally applicable to any form of consumer product.
SEABIRD: Scalable search for systematic biologically inspired design
Authors: Vandevenne Dennis , Verhaegen Paul-Armand , Dewulf Simon , Duflou Joost R.
Published: April 2015

As more and more people are increasingly turning to nature for design inspiration, tools and methodologies are developed to support the systematic bioideation process. State-of-the-art approaches struggle with expanding their knowledge bases because of interactive work required by humans per biological strategy. As an answer to this persistent challenge, a scalable search for systematic biologically inspired design (SEABIRD) system is proposed. This system leverages experience from the product aspects in design by analogy tool that identifies candidate products for between-domain design by analogy. SEABIRD is based on two conceptual representations, product and organism aspects, extracted from, respectively, a patent and a biological database, that enable leveraging the ever growing body of natural-language biological texts in the systematic bioinspired design process by eliminating interactive work by humans during corpus expansion. SEABIRD's search is illustrated and validated with three well-known biologically inspired design cases.
The effect of sarcopenic obesity on cardiovascular disease and all-cause mortality in older people
Authors: Atkins Janice L , Wannamethee S Goya
Published: April 2015

Obesity is a major public health problem with increasing prevalence worldwide. It is well recognized as a risk factor for cardiovascular morbidity and mortality in adult populations. Obesity prevalence is also increasing with age, and this may be particularly important in an ageing population. Ageing is associated with an increase in visceral fat and a progressive loss of muscle mass. Sarcopenia has been defined as the age-associated loss of skeletal muscle mass and has been associated with metabolic impairment, cardiovascular disease (CVD) risk factors, physical disability and mortality. Sarcopenia is often associated with obesity. Sarcopenic obesity is a new category of obesity in older adults who have high adiposity coupled with low muscle mass. Thus sarcopenia with obesity may synergistically increase their effect on metabolic disorders, CVD and mortality. This review focuses on the effects of sarcopenic obesity on the risk of cardiovascular disease and mortality in older adults.
Electron Microprobe and Raman Spectroscopy Investigation of an Oxygen-Bearing Pt–Fe–Pd–Ni–Cu Compound from Nurali Chromitite (Southern Urals, Russia)
Authors: Zaccarini Federica , Garuti Giorgio , Bakker Ronald J. , Pushkarev Evgeny
Published: April 2015

One grain, about 100×80μm in size, occurring in chromitite associated with the layered sequence of the Nurali mafic-ultramafic complex (Southern Urals, Russia) was investigated by electron-microprobe analyses and Raman spectroscopy. The grain is characterized by a spotty, rugged appearance and chemical zoning from which two compositions were calculated: (Pt0.35Pd0.26Fe0.22Cu0.01Ni0.05)0.98O1.02and (Fe0.90Pt0.58Ni0.28Pd0.13Cu0.08Rh0.01)1.98O1.02. In the lack of X-ray data, Raman spectroscopy established the presence of a diffuse 500–700 band and a sharp peak at 657 cm−1of relative wavenumber that strongly resemble the Raman spectra of synthetic PtO and PdO (palladinite). It is concluded that the Nurali grain probably represents a platinum group element (PGE) oxide, and does not consist of a mixture of PGE alloys with Fe oxide or hydroxide as reported for other natural PGE-O compounds.
A spatial analysis of incomes and institutional quality: evidence from US metropolitan areas
Authors: BOLOGNA JAMIE , YOUNG ANDREW T. , LACOMBE DONALD J.
Published: April 2015

We use the Stansel (2013) metropolitan area economic freedom index and 25 conditioning variables to analyze the spatial relationships between institutional quality and economic outcomes across 381 U.S. metropolitan areas. Specifically, we allow for spatial dependence in both the dependent and independent variables and estimate how economic freedom impacts both per capita income growth and per capita income levels. We find that economic freedom and per capita income growth and income levels are directly and positively related. Furthermore, we find that the total (direct plus indirect) effects on all metropolitan areas are positive and larger in magnitude than the direct effects alone, indicating that freedom-enhancing reforms in one metropolitan area lead to positive-sum games with neighboring metropolitan areas.
The output legitimacy of international organizations and the global public interest
Authors: Steffek Jens
Published: April 2015

In this article I seek to expand our understanding of the output legitimacy of international organizations (IOs). At the conceptual level, I refute the widespread view that output legitimacy is just a synonym for organizational effectiveness or efficiency. I argue instead that output legitimacy has an important democratic dimension. The touchstone of ‘democratic output legitimacy’ is the extent to which systems of governance produce results that cater to the public interest. Accordingly, the democratic output legitimacy of IOs can be understood in terms of their ability to safeguard the global public interest. This ability hinges upon their capacity to keep powerful factions in check, protect human rights, and safeguard a high epistemic quality of decisions. Attaining these qualities may require shielding IOs to some extent from the input dimension of the international political process. I do not, however, unconditionally praise de-politicization of IOs. I engage with the problem of technocratic paternalism, which is imminent when decision-making based on assumed citizen interests escapes confrontation with articulated citizen interests. The challenge is to devise global governance arrangements that enable an encompassing debate over the substance of the global public interest when needed, while keeping pressure from powerful factions at bay.
Change in and through practice: Pierre Bourdieu, Vincent Pouliot, and the end of the Cold War
Authors: Schindler Sebastian , Wille Tobias
Published: April 2015

The end of the Cold War led to intense debates about how change happens in international politics. In this article, we argue that practice theory has great potential for illuminating this question. Drawing on Vincent Pouliot’s empirical analysis of NATO-Russia relations after the end of the Cold War, we elaborate how change happens in and through practice. We show that post-Cold War security practices are inherently unstable, because there is a fundamental uncertainty about whether the Cold War is really over or whether the Cold War logic of bipolar confrontation still applies. Uncertainty about the meaning of the past destabilizes present practices and thus makes sudden and drastic change possible. To date, many contributions to the literature on international practices have, however, failed to grasp the inherent instability of practice. We argue that this failure is due to a particular conception of change that can be found in the works of Pierre Bourdieu. Through a close reading of Pouliot’s Bourdieusian analysis of post-Cold War politics, we demonstrate the limitations of such a perspective, notably that it is unable to grasp how change originates in practice.
Subcortical ischemic vascular disease: Roles of oligodendrocyte function in experimental models of subcortical white-matter injury
Authors: Shindo Akihiro , Liang Anna C , Maki Takakuni , Miyamoto Nobukazu , Tomimoto Hidekazu , Lo Eng H , Arai Ken
Published: April 2015

Oligodendrocytes are one of the major cell types in cerebral white matter. Under normal conditions, they form myelin sheaths that encircle axons to support fast nerve conduction. Under conditions of cerebral ischemia, oligodendrocytes tend to die, resulting in white-matter dysfunction. Repair of white matter involves the ability of oligodendrocyte precursors to proliferate and mature. However, replacement of lost oligodendrocytes may not be the only mechanism for white-matter recovery. Emerging data now suggest that coordinated signaling between neural, glial, and vascular cells in the entire neurovascular unit may be required. In this mini-review, we discuss how oligodendrocyte lineage cells participate in signaling and crosstalk with other cell types to underlie function and recovery in various experimental models of subcortical white-matter injury.
Detecting bit-flip errors in a logical qubit using stabilizer measurements
Authors: Ristè D. , Poletto S. , Huang M.-Z. , Bruno A. , Vesterinen V. , Saira O.-P. , DiCarlo L.
Published: April 2015

Quantum data are susceptible to decoherence induced by the environment and to errors in the hardware processing it. A future fault-tolerant quantum computer will use quantum error correction to actively protect against both. In the smallest error correction codes, the information in one logical qubit is encoded in a two-dimensional subspace of a larger Hilbert space of multiple physical qubits. For each code, a set of non-demolition multi-qubit measurements, termed stabilizers, can discretize and signal physical qubit errors without collapsing the encoded information. Here using a five-qubit superconducting processor, we realize the two parity measurements comprising the stabilizers of the three-qubit repetition code protecting one logical qubit from physical bit-flip errors. While increased physical qubit coherence times and shorter quantum error correction blocks are required to actively safeguard the quantum information, this demonstration is a critical step towards larger codes based on multiple parity measurements.
Nanoscale surface chemistry directs the tunable assembly of silver octahedra into three two-dimensional plasmonic superlattices
Authors: Lee Yih Hong , Shi Wenxiong , Lee Hiang Kwee , Jiang Ruibin , Phang In Yee , Cui Yan , Isa Lucio , Yang Yijie , Wang Jianfang , Li Shuzhou , Ling Xing Yi
Published: April 2015

A major challenge in nanoparticle self-assembly is programming the large-area organization of a single type of anisotropic nanoparticle into distinct superlattices with tunable packing efficiencies. Here we utilize nanoscale surface chemistry to direct the self-assembly of silver octahedra into three distinct two-dimensional plasmonic superlattices at a liquid/liquid interface. Systematically tuning the surface wettability of silver octahedra leads to a continuous superlattice structural evolution, from close-packed to progressively open structures. Notably, silver octahedra standing on vertices arranged in a square lattice is observed using hydrophobic particles. Simulations reveal that this structural evolution arises from competing interfacial forces between the particles and both liquid phases. Structure-to-function characterizations reveal that the standing octahedra array generates plasmonic ‘hotstrips’, leading to nearly 10-fold more efficient surface-enhanced Raman scattering compared with the other more densely packed configurations. The ability to assemble these superlattices on the wafer scale over various platforms further widens their potential applications.
Ablation of the p16INK4a tumour suppressor reverses ageing phenotypes of klotho mice
Authors: Sato Seidai , Kawamata Yuka , Takahashi Akiko , Imai Yoshinori , Hanyu Aki , Okuma Atsushi , Takasugi Masaki , Yamakoshi Kimi , Sorimachi Hiroyuki , Kanda Hiroaki , Ishikawa Yuichi , Sone Saburo , Nishioka Yasuhiko , Ohtani Naoko , Hara Eiji
Published: April 2015

The p16INK4a tumour suppressor has an established role in the implementation of cellular senescence in stem/progenitor cells, which is thought to contribute to organismal ageing. However, since p16INK4a knockout mice die prematurely from cancer, whether p16INK4a reduces longevity remains unclear. Here we show that, in mutant mice homozygous for a hypomorphic allele of the α-klotho ageing-suppressor gene (klkl/kl), accelerated ageing phenotypes are rescued by p16INK4a ablation. Surprisingly, this is due to the restoration of α-klotho expression in klkl/kl mice and does not occur when p16INK4a is ablated in α-klotho knockout mice (kl−/−), suggesting that p16INK4a is an upstream regulator of α-klotho expression. Indeed, p16INK4a represses α-klotho promoter activity by blocking the functions of E2Fs. These results, together with the observation that the expression levels of p16INK4a are inversely correlated with those of α-klotho throughout ageing, indicate that p16INK4a plays a previously unrecognized role in downregulating α-klotho expression during ageing.
Metazoans evolved by taking domains from soluble proteins to expand intercellular communication network
Authors: Nam Hyun-Jun , Kim Inhae , Bowie James U. , Kim Sanguk
Published: April 2015

A central question in animal evolution is how multicellular animals evolved from unicellular ancestors. We hypothesize that membrane proteins must be key players in the development of multicellularity because they are well positioned to form the cell-cell contacts and to provide the intercellular communication required for the creation of complex organisms. Here we find that a major mechanism for the necessary increase in membrane protein complexity in the transition from non-metazoan to metazoan life was the new incorporation of domains from soluble proteins. The membrane proteins that have incorporated soluble domains in metazoans are enriched in many of the functions unique to multicellular organisms such as cell-cell adhesion, signaling, immune defense and developmental processes. They also show enhanced protein-protein interaction (PPI) network complexity and centrality, suggesting an important role in the cellular diversification found in complex organisms. Our results expose an evolutionary mechanism that contributed to the development of higher life forms.