bluuebunny/crossref_metadata_2025 huggingface dataset:
Concise synthesis of atorvastatin lactone under high-speed vibration milling conditions
Authors: Estévez Verónica , Villacampa Mercedes , Menéndez J. Carlos
Published: April 2014

A Hantzsch-type multicomponent reaction under high-speed vibration milling conditions followed by acid treatment afforded atorvastatin lactone in 38% overall yield.
One-pot synthesis of cuboid WO3 crystal and its gas sensing properties
Authors: Wang Chong , Li Xin , Wang Biao , Ma Jian , Cao Yang , Sun Yanfeng , Lu Geyu
Published: April 2014

A simple solvothermal method was used for the synthesis of WO3, which exhibited a good response to NO2.
Depolymerization of polycarbonate with catalyst in hot compressed water in fused silica capillary and autoclave reactors
Authors: Pan Zhiyan , Hu Zhichao , Shi Yinghai , Shen Yuan , Wang Junliang , Chou I-Ming
Published: April 2014

The phase behavior of polycarbonate (PC) with or without catalyst in water during heating, reaction, and cooling processes was studied in the FSCR under a microscope and recorded using a digital camera and a computer.
Ruthenium-catalyzed cross-metathesis with electron-rich phenyl vinyl sulfide enables access to 2,3-dideoxy-d-ribopyranose ring system donors
Authors: Boutureira Omar , Isabel Matheu M. , Díaz Yolanda , Castillón Sergio
Published: April 2014

Microwave irradiation effectively accelerates the cross-metathesis reaction of 2-deoxy-d-ribose hydroxyalkene and derivatives with electron-rich phenyl vinyl sulfide using commercially available ruthenium-based catalysts, thus providing a flexible metal-mediated route to 2,3-dideoxy-d-ribopyranose ring system donors.
A rapid and modified approach for C-7 amination and amidation of 4-methyl-7-nonafluorobutylsulfonyloxy coumarins under microwave irradiation
Authors: Joy M. Nibin , Bodke Yadav D. , Khader K. K. Abdul , Ali Padusha M. Syed , Sajith Ayyiliyath M. , Muralidharan A.
Published: April 2014

A rapid approach for the synthesis of an array of 4-methyl-7-substituted coumarins has been developed.
Electrochemically prepared nanoporous gold as a SERS substrate with high enhancement
Authors: Fang Cheng , Shapter Joseph George , Voelcker Nicolas Hans , Ellis Amanda Vera
Published: April 2014

Gold films were electrochemically etched into nanoporous substrates with tuneable pore sizes down to approximately 2 nm. The SERS enhancement as a result of changes in valley and ligament widths of the nanoporous gold was investigated. Compared to the conventional de-alloyed nano-gold, the etched gold showed a lower limit of detection (2 × 10−9 M vs. 1 × 10−7 M Rhodamine 6G).
Organic hydroperoxide formation in the acid-catalyzed heterogeneous oxidation of aliphatic alcohols with hydrogen peroxide
Authors: Liu Qifan , Wang Weigang , Liu Ze , Wang Tianhe , Wu Lingyan , Ge Maofa
Published: April 2014

We present detailed mechanisms for the formation and degradation of organic hydroperoxide during the acid-catalyzed heterogeneous oxidation of aliphatic alcohols with hydrogen peroxide.
Deproto-metallation using mixed lithium–zinc and lithium–copper bases and computed CH acidity of 2-substituted quinolines
Authors: Marquise Nada , Bretel Guillaume , Lassagne Frédéric , Chevallier Floris , Roisnel Thierry , Dorcet Vincent , Halauko Yury S. , Ivashkevich Oleg A. , Matulis Vadim E. , Gros Philippe C. , Mongin Florence
Published: April 2014

The metallated quinolines were functionalized by iodolysis or aroylation.
Co-crystallized fullerene and a mixed (phthalocyaninato)(porphyrinato) dysprosium double-decker SMM
Authors: Wang Hailong , Qian Kang , Qi Dongdong , Cao Wei , Wang Kang , Gao Song , Jiang Jianzhuang
Published: April 2014

Investigation into a series of C60–[Dy(Pc)(TClPP)] cocrystallates reveals the inter-molecular interactions between C60 and [Dy(Pc)(TClPP)] molecules, which influence the SMM properties.
Assessing the potential of metal oxide semiconducting gas sensors for illicit drug detection markers
Authors: Hernández P. Tarttelin , Naik A. J. T. , Newton E. J. , Hailes Stephen M. V. , Parkin I. P.
Published: April 2014

Port security with a focus on drug trafficking prevention requires inexpensive and portable systems for on-site analysis of containers in order to minimise transit delays.
Improved dehydrogenation performance of LiBH4 by confinement into porous TiO2 micro-tubes
Authors: Liu Huiqiao , Jiao Lifang , Zhao Yanping , Cao Kangzhe , Liu Yongchang , Wang Yijing , Yuan Huatang
Published: April 2014

Porous TiO2 micro-tubes were fabricated by a solvothermal method, and the effect of TiO2 micro-tubes on the hydrogen desorption properties of LiBH4 was systematically investigated.
Design of liquid crystals with ‘de Vries-like’ properties: carbosilane-terminated 5-phenylpyrimidine mesogens suitable for chevron-free FLC formulations
Authors: Schubert Christopher P. J. , Bogner Andreas , Porada Jan H. , Ayub Khurshid , Andrea Tamer , Giesselmann Frank , Lemieux Robert P.
Published: April 2014

Carbosilane-terminated 5-phenylpyrimidine mesogens rank among the best ‘de Vries-like’ liquid crystals.
Non‐fragile state‐feedback control of uncertain piecewise‐affine slab systems with input constraints: a convex optimisation approach
Authors: Dadkhah Navid , Rodrigues Luis
Published: April 2014

The main contribution of this work is to propose a design technique for state‐feedback control of continuous‐time piecewise‐affine (PWA) systems that is robust not only to the system uncertainties, but also to variations of the controller gains. More specifically, this study presents sufficient conditions to synthesise a robust non‐fragile PWA controller that exponentially stabilises the closed‐loop equilibrium point. Furthermore, these conditions are cast as an optimisation problem subject to a set of linear matrix inequalities (LMIs), which can then be solved efficiently. In addition, a set of LMI conditions are derived to ensure that the control input will always meet a pre‐assigned upper bound. Simulation results demonstrate the effectiveness of the proposed approach.
Adaptive neural observer‐based backstepping fault tolerant control for near space vehicle under control effector damage
Authors: Jiang Bin , Xu Dezhi , Shi Peng , Lim Cheng Chew
Published: April 2014

In this study, a theoretical framework for reconfigurable flight control is developed and applied to near space vehicle (NSV) attitude dynamics. First, NSV reentry mode is described. Second, an adaptive neural network observer is proposed, which ensures asymptotic convergence of the state observer error to zero under control effector damage and uncertainty. Next, a reconfigurable command‐filter backstepping controller is designed based on the adaptive neural network observer. The authors focus is on the accommodation of the control effector damage, uncertainty and resulting disturbances. It is shown that the presented new control design results in asymptotic convergence of the attitude tracking error to zero. Finally, simulation results are given to demonstrate the effectiveness and potential of the proposed fault tolerant control scheme.
Single electron states in polyethylene
Authors: Wang Y. , MacKernan D. , Cubero D. , Coker D. F. , Quirke N.
Published: April 2014

We report computer simulations of an excess electron in various structural motifs of polyethylene at room temperature, including lamellar and interfacial regions between amorphous and lamellae, as well as nanometre-sized voids. Electronic properties such as density of states, mobility edges, and mobilities are computed on the different phases using a block Lanczos algorithm. Our results suggest that the electronic density of states for a heterogeneous material can be approximated by summing the single phase density of states weighted by their corresponding volume fractions. Additionally, a quantitative connection between the localized states of the excess electron and the local atomic structure is presented.
The rigorous stochastic matrix multiplication scheme for the calculations of reduced equilibrium density matrices of open multilevel quantum systems
Authors: Chen Xin
Published: April 2014

Understanding the roles of the temporary and spatial structures of quantum functional noise in open multilevel quantum molecular systems attracts a lot of theoretical interests. I want to establish a rigorous and general framework for functional quantum noises from the constructive and computational perspectives, i.e., how to generate the random trajectories to reproduce the kernel and path ordering of the influence functional with effective Monte Carlo methods for arbitrary spectral densities. This construction approach aims to unify the existing stochastic models to rigorously describe the temporary and spatial structure of Gaussian quantum noises. In this paper, I review the Euclidean imaginary time influence functional and propose the stochastic matrix multiplication scheme to calculate reduced equilibrium density matrices (REDM). In addition, I review and discuss the Feynman-Vernon influence functional according to the Gaussian quadratic integral, particularly its imaginary part which is critical to the rigorous description of the quantum detailed balance. As a result, I establish the conditions under which the influence functional can be interpreted as the average of exponential functional operator over real-valued Gaussian processes for open multilevel quantum systems. I also show the difference between the local and nonlocal phonons within this framework. With the stochastic matrix multiplication scheme, I compare the normalized REDM with the Boltzmann equilibrium distribution for open multilevel quantum systems.
DNA strand breaks and crosslinks induced by transient anions in the range 2-20 eV
Authors: Luo Xinglan , Zheng Yi , Sanche Léon
Published: April 2014

The energy dependence of the yields of single and double strand breaks (SSB and DSB) and crosslinks induced by electron impact on plasmid DNA films is measured in the 2-20 eV range. The yield functions exhibit two strong maxima, which are interpreted to result from the formation of core-excited resonances (i.e., transient anions) of the bases, and their decay into the autoionization channel, resulting in π → π* electronic transitions of the bases followed by electron transfer to the C–O σ* bond in the phosphate group. Occupancy of the σ* orbital ruptures the C–O bond of the backbone via dissociative electron attachment, producing a SSB. From a comparison of our results with those of other works, including theoretical calculations and electron-energy-loss spectra of the bases, the 4.6 eV peak in the SSB yield function is attributed to the resonance decay into the lowest electronically excited states of the bases; in particular, those resulting from the transitions 13A′ (π2 → π3*) and 13A″ (n2 → π3*) of thymine and 13A′ (π → π*) of cytosine. The strongest peak at 9.6 eV in the SSB yield function is also associated with electron captured by excited states of the bases, resulting mostly from a multitude of higher-energy π → π* transitions. The DSB yield function exhibits strong maxima at 6.1 and 9.6 eV. The peak at 9.6 eV is probably related to the same resonance manifold as that leading to SSB, but the other at 6.1 eV may be more restricted to decay into the electronic state 13A′ (π → π*) of cytosine via autoionization. The yield function of crosslinks is dominated by a broad peak extending over the 3.6-11.6 eV range with a sharper one at 17.6 eV. The different line shape of the latter function, compared to that of SSB and DSB, appears to be due to the formation of reactive radical sites in the initial supercoiled configuration of the plasmid, which react with the circular form (i.e., DNA with a SSB) to produce a crosslink.
Pressure induced magneto-structural phase transitions in layered RMn2X2 compounds (invited)
Authors: Kennedy Shane , Wang Jianli , Campbell Stewart , Hofmann Michael , Dou Shixue
Published: April 2014

We have studied a range of pseudo-ternaries derived from the parent compound PrMn2Ge2, substituting for each constituent element with a smaller one to contract the lattice. This enables us to observe the magneto-elastic transitions that occur as the Mn-Mn nearest neighbour distance is reduced and to assess the role of Pr on the magnetism. Here, we report on the PrMn2Ge2−xSix, Pr1−xYxMn2Ge2, and PrMn2−xFexGe2 systems. The pressure produced by chemical substitution in these pseudo-ternaries is inherently non-uniform, with local pressure variations dependent on the local atomic distribution. We find that concentrated chemical substitution on the R or X site (e.g., in Pr0.5Y0.5Mn2Ge2 and PrMn2Ge0.8Si1.2) can produce a separation into two distinct magnetic phases, canted ferromagnetic and canted antiferromagnetic, with a commensurate phase gap in the crystalline lattice. This phase gap is a consequence of the combination of phase separation and spontaneous magnetostriction, which is positive on transition to the canted ferromagnetic phase and negative on transition to the canted antiferromagnetic phase. Our results show that co-existence of canted ferromagnetic and antiferromagnetic phases depends on chemical pressure from the rare earth and metalloid sites, on local lattice strain distributions and on applied magnetic field. We demonstrate that the effects of chemical pressure bear close resemblance to those of mechanical pressure on the parent compound.
Topologically massive Yang-Mills: A Hamilton-Jacobi constraint analysis
Authors: Bertin M. C. , Pimentel B. M. , Valcárcel C. E. , Zambrano G. E. R.
Published: April 2014

We analyse the constraint structure of the topologically massive Yang-Mills theory in instant-form and null-plane dynamics via the Hamilton-Jacobi formalism. The complete set of hamiltonians that generates the dynamics of the system is obtained from the Frobenius’ integrability conditions, as well as its characteristic equations. As generators of canonical transformations, the hamiltonians are naturally linked to the generator of Lagrangian gauge transformations.
Analytical model for the effects of wetting on thermal boundary conductance across solid/classical liquid interfaces
Authors: Caplan Matthew E. , Giri Ashutosh , Hopkins Patrick E.
Published: April 2014

We develop an analytical model for the thermal boundary conductance between a solid and a liquid. By infusing recent developments in the phonon theory of liquid thermodynamics with diffuse mismatch theory, we derive a closed form model that can predict the effects of wetting on the thermal boundary conductance across an interface between a solid and a classical liquid. We account for the complete wetting (hydrophilicity), or lack thereof (hydrophobicity), of the liquid to the solid by considering varying contributions of transverse mode interactions between the solid and liquid interfacial layers; this transverse coupling relationship is determined with local density of states calculations from molecular dynamics simulations between Lennard-Jones solids and a liquids with different interfacial interaction energies. We present example calculations for the thermal boundary conductance between both hydrophobic and hydrophilic interfaces of Al/water and Au/water, which show excellent agreement with measured values reported by Ge et al. [Z. Ge, D. G. Cahill, and P. V. Braun, Phys. Rev. Lett. 96, 186101 (2006)]. Our model does not require any fitting parameters and is appropriate to model heat flow across any planar interface between a solid and a classical liquid.
Nonlinear buckling analyses of a small-radius carbon nanotube
Authors: Liu Ning , Wang Yong-Gang , Li Min , Jia Jiao
Published: April 2014

Carbon nanotube (CNT) was first discovered by Sumio Iijima. It has aroused extensive attentions of scholars from all over the world. Over the past two decades, we have acquired a lot of methods to synthesize carbon nanotubes and learn their many incredible mechanical properties such as experimental methods, theoretical analyses, and computer simulations. However, the studies of experiments need lots of financial, material, and labor resources. The calculations will become difficult and time-consuming, and the calculations may be even beyond the realm of possibility when the scale of simulations is large, as for computer simulations. Therefore, it is necessary for us to explore a reasonable continuum model, which can be applied into nano-scale. This paper attempts to develop a mathematical model of a small-radius carbon nanotube based on continuum theory. An Isotropic circular cross-section, Timoshenko beam model is used as a simplified mechanical model for the small-radius carbon nanotube. Theoretical part is mainly based on modified couple stress theory to obtain the numerical solutions of buckling deformation. Meanwhile, the buckling behavior of the small radius carbon nanotube is simulated by Molecular Dynamics method. By comparing with the numerical results based on modified couple stress theory, the dependence of the small-radius carbon nanotube mechanical behaviors on its elasticity constants, small-size effect, geometric nonlinearity, and shear effect is further studied, and an estimation of the small-scale parameter of a CNT (5, 5) is obtained.
Temperature-dependent Raman and ultraviolet photoelectron spectroscopy studies on phase transition behavior of VO2 films with M1 and M2 phases
Authors: Okimura Kunio , Hanis Azhan Nurul , Hajiri Tetsuya , Kimura Shin-ichi , Zaghrioui Mustapha , Sakai Joe
Published: April 2014

Structural and electronic phase transitions behavior of two polycrystalline VO2 films, one with pure M1 phase and the other with pure M2 phase at room temperature, were investigated by temperature-controlled Raman spectroscopy and ultraviolet photoelectron spectroscopy (UPS). We observed characteristic transient dynamics in which the Raman modes at 195 cm−1 (V-V vibration) and 616 cm−1 (V-O vibration) showed remarkable hardening along the temperature in M1 phase film, indicating the rearrangements of V-V pairs and VO6 octahedra. It was also shown that the M1 Raman mode frequency approached those of invariant M2 peaks before entering rutile phase. In UPS spectra with high energy resolution of 0.03 eV for the M2 phase film, narrower V3d band was observed together with smaller gap compared to those of M1 phase film, supporting the nature of Mott insulator of M2 phase even in the polycrystalline film. Cooperative behavior of lattice rearrangements and electronic phase transition was suggested for M1 phase film.
University of Lodz an electron spectrometer—A new conversion-electron spectrometer for “in-beam” measurements
Authors: Perkowski J. , Andrzejewski J. , Janiak Ł. , Samorajczyk J. , Abraham T. , Droste Ch. , Grodner E. , Hadyńska-Klęk K. , Kisieliński M. , Komorowska M. , Kowalczyk M. , Kownacki J. , Mierzejewski J. , Napiorkowski P. , Korman A. , Srebrny J. , Stolarz A. , Zielińska M.
Published: April 2014

The designed and constructed at the University of Lodz an electron spectrometer is devoted to “in-beam” measurements. The apparatus is characterized by high efficiency up to 9%, good energy resolution (FWHM = 5 keV at 482 keV) and, what is very important good suppression of delta electrons, positrons, and photons emitted by the targets. This achievement was obtained using a combination of magnetic field in two different layouts: perpendicular and parallel to the axis of the spectrometer being orthogonal to the beamline. The conversion-electron spectrometer coupled to the EAGLE array was successfully tested in an “in-beam” measurement.
Comparison of direct simulation Monte Carlo chemistry and vibrational models applied to oxygen shock measurements
Authors: Wysong Ingrid , Gimelshein Sergey , Bondar Yevgeniy , Ivanov Mikhail
Published: April 2014

Validation of three direct simulation Monte Carlo chemistry models—total collision energy, Quantum Kinetic, and Kuznetsov state specific (KSS)—is conducted through the comparison of calculated vibrational temperatures of molecular oxygen with measured values inside a normal shock wave. First, the 2D geometry and numerical approach used to simulate the shock experiments is verified. Next, two different vibrational relaxation models are validated by comparison with data for the M = 9.3 case where dissociation is small in the nonequilibrium region of the shock and with newly obtained thermal rates. Finally, the three chemistry model results are compared for M = 9.3 and 13.4 in the region where the vibrational temperature is greatly different from the rotational and translational temperature, and thus nonequilibrium dissociation is important. It is shown that the peak vibrational temperature is very sensitive to the initial nonequilibrium rate of reaction in the chemistry model and that the vibrationally favored KSS model is much closer to the measured peak, but the post-peak behavior indicates that some details of the model still need improvement.
Experimental study of fluid flows in a precessing cylindrical annulus
Authors: Lin Yufeng , Noir Jerome , Jackson Andrew
Published: April 2014

The flow inside a precessing fluid cavity has been given particular attention since the end of the 19th century in geophysical and industrial contexts. The present study aims at shedding light on the underlying mechanism by which the flow inside a precessing cylindrical annulus transitions from laminar to multiple scale complex structures. We address this problem experimentally using ultrasonic Doppler velocimetry to diagnose the fluid velocity in a rotating and precessing cylindrical annulus. When precession is weak, the flow can be described as a superposition of forced inertial modes. Above a critical value of the precession rate, the forced flow couples with two free inertial modes satisfying triadic resonance conditions, leading to the classical growth and collapse. Using a Bayesian approach, we extract the wavenumber, frequency, growth rate, and amplitude of each mode involved in the instability. In some cases, we observe for the first time ever experimentally two pairs of free modes coexisting with the forced flow. At larger precession rates, we do not observe triadic resonance any more, instead we observe several harmonics whose frequencies are integer multiples of the rotation frequency.
Some improvements in the theory of plasma relaxation
Authors: Hameiri Eliezer
Published: April 2014

Taylor's relaxation theory is extended to plasmas with mass flow by using the cross helicity as a conserved quantity, similar to the magnetic helicity. Indeed, it is shown that the conservation of the cross helicity in magnetohydrodynamics is the result of the conservation of two magnetic-like helicities in two-fluid plasmas. In addition, the usually ignored toroidal flux is also held to be conserved. We also view plasma relaxation as attaining a maximum entropy state rather than Taylor's minimum energy state, but prove that maximizing the entropy subject to a given amount of energy is equivalent to minimizing the energy subject to a given amount of entropy. The resulting relaxed state is similar to the one discussed by Finn and Antonsen [Phys. Fluids 26, 3540 (1983)], and involves flow parallel to the magnetic field and constant temperature, but non-constant pressure. We show how to construct an asymptotic solution to the relaxed state based on the smallness of the Alfven Mach number of the flow.
Efficient modeling of photonic crystals with local Hermite polynomials
Authors: Boucher C. R. , Li Zehao , Albrecht J. D. , Ram-Mohan L. R.
Published: April 2014

Developing compact algorithms for accurate electrodynamic calculations with minimal computational cost is an active area of research given the increasing complexity in the design of electromagnetic composite structures such as photonic crystals, metamaterials, optical interconnects, and on-chip routing. We show that electric and magnetic (EM) fields can be calculated using scalar Hermite interpolation polynomials as the numerical basis functions without having to invoke edge-based vector finite elements to suppress spurious solutions or to satisfy boundary conditions. This approach offers several fundamental advantages as evidenced through band structure solutions for periodic systems and through waveguide analysis. Compared with reciprocal space (plane wave expansion) methods for periodic systems, advantages are shown in computational costs, the ability to capture spatial complexity in the dielectric distributions, the demonstration of numerical convergence with scaling, and variational eigenfunctions free of numerical artifacts that arise from mixed-order real space basis sets or the inherent aberrations from transforming reciprocal space solutions of finite expansions. The photonic band structure of a simple crystal is used as a benchmark comparison and the ability to capture the effects of spatially complex dielectric distributions is treated using a complex pattern with highly irregular features that would stress spatial transform limits. This general method is applicable to a broad class of physical systems, e.g., to semiconducting lasers which require simultaneous modeling of transitions in quantum wells or dots together with EM cavity calculations, to modeling plasmonic structures in the presence of EM field emissions, and to on-chip propagation within monolithic integrated circuits.
Measuring size dependent electrical properties from nanoneedle structures: Pt/ZnO Schottky diodes
Authors: Mao Shimin , Shang Tao , Park Byoungnam , Anderson Daniel D. , Dillon Shen J.
Published: April 2014

This work reports the fabrication and testing of nanoneedle devices with well-defined interfaces that are amenable to a variety of structural and electrical characterization, including transmission electron microscopy. Single Pt/ZnO nanoneedle Schottky diodes were fabricated by a top down method using a combination of electro-polishing, sputtering, and focused ion beam milling. The resulting structures contained nanoscale planar heterojunctions with low ideality factors, the dimensions of which were tuned to study size-dependent electrical properties. The diameter dependence of the Pt/ZnO diode barrier height is explained by a joule heating effect and/or electronic inhomogeneity in the Pt/ZnO contact area.
Micro-electro-mechanically tunable metamaterial with enhanced electro-optic performance
Authors: Pitchappa Prakash , Pei Ho Chong , Lin Yu-Sheng , Kropelnicki Piotr , Huang Chia-Yi , Singh Navab , Lee Chengkuo
Published: April 2014

We experimentally demonstrate a micro-electro-mechanically tunable metamaterial with enhanced electro-optical performance by increasing the number of movable cantilevers in the symmetrical split ring resonator metamaterial unit cell. Simulations were carried out to understand the interaction of the incident terahertz radiation with out-of-plane deforming metamaterial resonator. In order to improve the overall device performance, the number of released cantilever in a unit cell was increased from one to two, and it was seen that the tunable range was doubled and the switching contrast improved by a factor of around five at 0.7 THz. This simple design approach can be adopted for a wide range of high performance electro-optical devices such as continuously tunable filters, modulators, and electro-optic switches to enable future photonic circuit applications.
Voltage noise across a metal/metal sliding contact as a probe of the surface state
Authors: Chevallier E. , Bourny V. , Bouzerar R. , Fortin J. , Durand-Drouhin O. , Da Ros V.
Published: April 2014

We report a complete experimental study and a physical modelling of the long-term evolution of the main electrical properties of a metal ring/wire sliding contact, the wire, and the ring being coated with a thin Au film. The long-term evolution of the Au/Au sliding contact was characterized through the measurement and tracking of relevant quantities such as the voltage noise across the contact, revealing the ageing of the contact. A phenomenological approach to the sliding contact, coupling both electrical and mechanical aspects, allows a sensible interpretation of the experimental results. This approach retains three contributions to the voltage noise operating at different scales, namely the rings surface geometry, chemical composition fluctuations of the coated rings, and the mesoscopic structure of the contact. A fundamental distinction between these sources is established, owing to their effects relying on either the mechanical contact losses or resistance fluctuations. We finally show that the determination and tracking of these noise sources using reasonable specific indexes lead to reliable criterions of the electrical contact quality.
Vertical force acting on partly submerged spindly cylinders
Authors: Zhang Xinbin , Yan Jihong , Zhao Jie , Wang Yanan , Pan Qinmin
Published: April 2014

When an object is placed on a water surface, the air-water interface deforms and a meniscus arises due to surface tension effects, which in turn produces a lift force or drag force on the partly submerged object. This study aims to investigate the underlying mechanism of the vertical force acting on spindly cylinders in contact with a water surface. A simplified 2-D model is presented, and the profile of the curved air-water interface and the vertical force are computed using a numerical method. A parametric study is performed to determine the effects of the cylinder center distance, inclined angle, static contact angle, and radius on the vertical force. Several key conclusions are derived from the study: (1) Although the lift force increases with the cylinder center distance, cylinders with smaller center distances can penetrate deeper below the water surface before sinking, thereby obtaining a larger maximum lift force; (2) An increase in the inclined angle reduces the lift force, which can enable the lower cylinders fall more deeply before sinking; (3) While the effect of static contact angle is limited for angles greater than 90°, hydrophobicity allows cylinders to obtain a larger lift force and load capacity on water; (4) The lift force increases rapidly with cylinder radius, but an increase in radius also increases the overall size and weight of cylinders and decreases the proportion of the surface tension force. These findings may prove helpful in the design of supporting legs of biologically-inspired miniature aquatic devices, such as water strider robots.
The Ruth First Papers Project: digitising the Ruth First archive
Authors: Rockel Vanessa , Mahon Matt
Published: April 2014

Soon after Ruth First was murdered in 1982 an appeal went out for funds to create a Trust in Ruth's name. In the 1980s the Trust found a home for Ruth's papers and documents at the Institute of Commonwealth Studies (ICwS) in London under Shula Marks' directorship. The hope was that the archive would be part of a centre that would study southern African liberation, continuing work that had been brutally cut short by Ruth's murder in Maputo. In 2012 the ICwS launched the Ruth First Papers Project, which aims to digitise the archive of Ruth's papers. A dedicated website was established where the first selection of documents has been made available for anyone (anywhere) to consult. In this brief introduction, Rockel and Mahon – researchers on the project – describe the process of selecting documents for digitisation and the experience of encountering Ruth in the archives.
Remembering Ruth First at the CEA
Authors: Darch Colin
Published: April 2014

Ruth changed in Mozambique; she softened. I think she belonged in Mozambique in a way that she never belonged to England. It was her home, and she meant something to that society. (Gillian Slovo, interview, 1989)

This article traces the evolution of research at the Centro de Estudos Africanos (CEA) from before the time of Ruth First's arrival. It divides her work there into two periods: the work on the Mozambican Miner, in which she was heavily involved personally, and the later period when she was much more involved in recruiting permanent staff and in creating conditions for successful research, including building up the Documentation Centre within the CEA. This objective included work on maintaining the administrative independence of the CEA within the university to ensure flexibility in responding to rapidly changing research conditions. Research was not simply determined by political priorities, although it engaged with them. The evolution of the key Development Course is also traced, and the work of the Oficina de Historia (History Workshop) is briefly described.
Building an alternative consensus for political action: Ruth First as journalist and activist
Authors: Pinnock Don
Published: April 2014

Ruth First's early work as a journalist and political activist in South Africa became an inspiration for later generations of journalists and political writers. Here Don Pinnock, himself a journalist by trade, recounts how he rediscovered her writing of the 1950s in a new phase of political questioning and revolutionary activity in the 1980s. He pinpoints her talent as a reporter of events and conditions of the times to create an alternative consensus about race and class in South Africa.
‘Today is human rights day’: Ruth First, human rights and the United Nations
Authors: Harlow Barbara
Published: April 2014

It is not well known that Ruth First found an opening to debates on the world stage by working as a consultant for the United Nations whilst she was still in South Africa and whilst in exile. The author describes the projects she was engaged on and her motivation in this work. She links Ruth's participation to the emergence of human rights discourse, seen as a means to condemn apartheid in South Africa, whilst also regarded sceptically.
Transient expression analysis revealed the importance of VTC2 expression level in light/dark regulation of ascorbate biosynthesis in Arabidopsis
Authors: Yoshimura Kazuya , Nakane Tomono , Kume Seina , Shiomi Yuki , Maruta Takanori , Ishikawa Takahiro , Shigeoka Shigeru
Published: April 2014

Ascorbate (AsA) is an important antioxidant and an enzyme cofactor involved in various metabolic pathways. In this study, we investigated the effects of estrogen (ES)-inducible transient expression of genes encoding enzymes involved in the d-mannose/l-galactose (d-Man/l-Gal) pathway for plant AsA biosynthesis on AsA levels under light and dark conditions. No significant difference was observed in AsA levels between Arabidopsis plants transiently expressing phosphomannose isomerase (PMI1), GDP-d-Man pyrophosphorylase (GMP/VTC1), GDP-Man-3′,5′-epimerase (GME), and l-Gal 1-phosphate phosphatase (GPP/VTC4), but AsA levels in the plants transiently expressing GDP-l-Gal phosphorylase (GGP/VTC2) were 2.5-fold higher than those in control plants 7 d after ES treatment. The increase in AsA levels under continuous light conditions and the decrease in AsA levels under dark conditions were enhanced and suppressed, respectively, in the ES-treated plants. These results suggest that GGP/VTC2 acts as a rate-limiting step regulating AsA biosynthesis in response to light and dark conditions.
Effects of heparin and cholesterol sulfate on the activity and stability of human matrix metalloproteinase 7
Authors: Samukange Vimbai , Yasukawa Kiyoshi , Inouye Kuniyo
Published: April 2014

Sulfated glycosaminoglycans and sulfated lipids are involved in the biological functions of human matrix metalloproteinase 7 (MMP-7). In this study, the effects of heparin and cholesterol sulfate (CS) on the activity and stability of MMP-7 in the hydrolysis of a synthetic substrate, (7-methoxycoumarin-4-yl)acetyl-l-Pro-l-Leu-Gly-l-Leu-[N3-(2,4-dinitrophenyl)-l-2,3-diaminopropionyl]-l-Ala-l-Arg-NH2, were examined. Heparin increased activity by decreasing Km, and the Km values for 0 and 50 μM heparin were 57 ± 8 and 19 ± 5 μM, respectively. CS decreased activity in a non-competitive inhibitory manner with a Ki value of 11 ± 3 μM. In thermal incubation at 50−70 °C, heparin increased relative activity (the ratio of kcat/Km of MMP-7 with incubation to that without it), while CS decreased relative activity. These results indicate that heparin increases the activity and stability of MMP-7, while CS decreases them.
Characterization of chimeric and mutated isocitrate lyases of a mesophilic nitrogen-fixing bacterium, Azotobacter vinelandii, and a psychrophilic bacterium, Colwellia maris
Authors: Hayashi Tomofumi , Matsuzaki Wataru , Takada Yasuhiro
Published: April 2014

Chimeric enzymes between a cold-adapted isocitrate lyase (ICL) of a psychrophilic bacterium, Colwellia maris, (CmICL) and a mesophilic ICL of a nitrogen-fixing bacterium, Azotobacter vinelandii, (AvICL) were constructed by dividing the ICL genes into four regions of almost equal length and exchanging regions in various combinations. The chimeric ICL, which was replaced C-terminal region 4 of AvICL by the corresponding region of CmICL, showed much lower specific activity and lower optimum temperature and thermostability for activity than wild-type AvICL, indicating that region 4 is involved in its thermal properties. Furthermore, mutual substitution between the Met501 residue in region 4 of CmICL and the corresponding Ile504 residue of AvICL influenced the temperature dependence of their activities, suggesting that these amino acid residues are important to the respective mesophilic and cold-adapted properties of AvICL and CmICL.
Acyl-homoserine lactones suppresses IEC-6 cell proliferation and increase permeability of isolated rat colon
Authors: Joe Ga-Hyun , Andoh Midori , Nomura Mikako , Iwaya Hitoshi , Lee Jae-Sung , Shimizu Hidehisa , Tsuji Youhei , Maseda Hideaki , Miyazaki Hitoshi , Hara Hiroshi , Ishizuka Satoshi
Published: April 2014

We investigated to determine whether a variety of acyl-homoserine lactones (AHLs) influences epithelial cell proliferation and mucosal permeability. 3-Oxo-C12-homoserine lactone (HSL) and 3-oxo-C14-HSL significantly suppressed IEC-6 cell proliferation. A significant increase in mucosal permeability was observed in isolated rat colon tissue exposed to C12-HSL, 3-oxo-C12-HSL, and 3-oxo-C14-HSL. These data indicate that AHLs suppress epithelial proliferation and disrupt barrier function in intestinal mucosa.
Genetic and biochemical analysis of the antibiotic biosynthetic gene clusters on the Streptomyces linear plasmid
Authors: Arakawa Kenji
Published: April 2014

We extensively analyzed the giant linear plasmid pSLA2-L in Streptomyces rochei 7434AN4, a producer of two structurally unrelated polyketide antibiotics, lankacidin and lankamycin. It was found that amine oxidase LkcE oxidizes an acyclic amine to an imine, which is in turn converted to the 17-membered carbocyclic lankacidin. Heterologous expression and translational fusion experiments indicated the modular-iterative mixed polyketide biosynthesis of lankacidin. Concerning to lankamycin biosynthesis, starter unit biosynthesis and the post-PKS modification pathway were elucidated by feeding and gene inactivation experiments. It was shown that pSLA2-L contains many regulatory genes, which constitute the signaling molecule/receptor system for antibiotic production and morphological differentiation in this strain. Two signaling molecules, SRB1 and SRB2, that induce production of lankacidin and lankamycin were further isolated and their structures were elucidated. Each contains a 2,3-disubstituted butenolide skeleton, and the stereochemistry at C-1′ position is crucial for inducing activity.
Administered chrysanthemum flower oil attenuates hyperuricemia: mechanism of action as revealed by DNA microarray analysis
Authors: Honda Shinichi , Kawamoto Seiji , Tanaka Hozumi , Kishida Hideyuki , Kitagawa Masayasu , Nakai Yuji , Abe Keiko , Hirata Dai
Published: April 2014

We applied Chrysanthemum flower oil (CFO) to a hyperuricemia model by feeding rats a hyperuricemia-inducing diet (HID) and investigated its effect on serum uric acid (SUA) levels and its mode of action. CFO is the oily fraction that contains polyphenols derived from chrysanthemum flowers. Oral administration of CFO to HID-fed rats significantly decreased their SUA levels. It also inhibited xanthine oxidase activities in the liver and increased urine uric acid levels. The effects of CFO on the renal gene expressions that accompanied the induction of hyperuricemia were comprehensively confirmed by DNA microarray analysis. The analysis showed up-regulation of those genes for uric acid excretion by CFO administration. These results suggest that CFO suppresses the increase in SUA levels via two mechanisms: suppression of uric acid production by inhibition of xanthine oxidase in the liver and acceleration of its excretion by up-regulation of uric acid transporter genes in the kidney.
Terpenoids from Tripterygium hypoglaucum and their inhibition of LPS-induced NO production
Authors: Zhao Peng , Wang Hao , Jin Da-Qing , Ohizumi Yasushi , Xu Jing , Guo Yuanqiang
Published: April 2014

One new (1) and three known (2–4) sesquiterpenes and four known diterpenes (5–8) were isolated from the root bark of Tripterygium hypoglaucum. Their structures were elucidated on the basis of extensive spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D-NMR, and 2D-NMR). The inhibitory activity toward LPS-induced NO production of these terpenoids was evaluated, all the compounds showing inhibitory effects.
Phenolic components from the stem of Acanthopanax koreanum and their inhibitory effects on NF-kappa B
Authors: Sun Ya Nan , Li Wei , Yan Xi Tao , Yang Seo Young , Song Seok Bean , Kim Young Ho
Published: April 2014

Two novel phenolic glucosides (1–2), as well as seven known compounds (3–9), were isolated from the stem of Acanthopanax koreanum; their chemical structures were determined by chemical and spectroscopic methods and subsequently compared with previously reported data. Their inhibition of nuclear factor kappa B (NF-κB) was measured in human embryonic kidney (293T) cells by using an NF-κB luciferase assay.
Theasaponin E1 as an effective ingredient for anti-angiogenesis and anti-obesity effects
Authors: Kim Jong-Deog , Chaudhary Narendra , Seo Hyo-Jin , Kim Min-Yong , Shin Tai-Sun
Published: April 2014

Theasaponin E1 (TSE1) has been suggested to have higher biological activity than other saponins present in tea seed. Saponins have recently been considered as a potential chemotherapeutic agent for treating cancer. We examined the anti-angiogenic and anti-obesity properties of TSE1 contributing to anti-cancer efficacy. Treating with a 10 μg/mL concentration of TSE1 completely inhibited tube formation in human umbilical vein endothelial cells (HUVECs). TSE1 showed toxicity toward cancer cells and inhibited in vivo growth of the tumor. The vascular endothelial growth factor (VEGF) receptor complex was suppressed, leading to the inhibition of protein kinase B (Akt) expression and down-regulation of nuclear factor-kappa B (NF-kB) activation. The differentiating 3T3-L1 cells treated with TSE1 had decreased lipid droplet formation measured by Oil Red O staining. Reduced weight was measured in mice fed with a TSE1 plus high-fat diet. The results taken together, and particularly the NF-kB inhibition, suggest that TSE1 may have multi-target action for treating cancer as a novel chemotherapeutic agent.
What Defendants Say in Response to Their Offenses
Authors: Gruber M. Catherine
Published: April 2014

This chapter examines the ways in which defendants developed the topic of their offense. In general, they either focused on the offense itself, such as by making a critical assessment of their actions, or they offered a response to the offense, perhaps with a conventional apology (e.g., “I’m sorry”). The chapter argues that speaking in more performative ways (Austin 1962) indexes defendants as seeking to accomplish a particular goal. In the context of sentencing, that goal is understood as sentence related. The interest that defendants are understood as having in the sentence, however, undermines the sincerity necessary for a sincere-sounding apology. In addition, defendants’ references to their offenses were strikingly vague. Depending on the lens that is applied, expressions such as “what I did” and “my actions” can be understood as either a defensive strategy or a natural consequence of a focus on a different element of the utterance.
Spanish Imposters and Verbal Agreement
Authors: Dudley Rachel
Published: April 2014

Chapter 3 provides evidence for a subject clitic doubling mechanism in Spanish by bringing together two different empirical observations. The first observation comes from new research on agreement with Spanish imposters that singular imposters like un servidor — “a servant” — allow only third-person verbal agreement and that plural imposters like unos servidores — “some servants” — optionally allow both first- and third-person agreement. The second observation comes from a fresh look at analyses of Spanish verbal morphology, which indicates that apparent inflectional morphemes on plural verb forms might actually be incorporated subject clitics. The argument is that observed singular/plural asymmetries in both domains (agreement with imposters and verbal paradigms) can be derived from the same underlying asymmetry in clitic doubling.
The Syntax of Indonesian Imposters
Authors: Kaufman Daniel
Published: April 2014

The languages of West Indonesia shed a unique and valuable light on imposter phenomena in comprising the only attested case of imposters being treated differently from homophonous non-imposters in the overt syntax. This chapter looks at the best studied of these languages, Indonesian. Indonesian takes part in the widely attested East Asian sprachbund phenomenon of employing titles and terms of kin as polite pronouns. Unlike the vast majority of other East Asian languages, however, Indonesian shows incipient person agreement on verbs. Entire referring expressions are employed as agreement markers, procliticizing to the verb on analogy with regular person prefixes. Because agreement only takes place with local ([+1], [+2]) persons, a positional difference arises between referring expressions that have a third person reference, and those that have a first or second person reference, with only the latter procliticizing. The chapter examines the syntax of this proclisis and its consequences for the theory of imposters.
The intonational phonology of Tamil
Authors: Keane Elinor
Published: April 2014

This chapter presents a first survey of the intonational phonology of Tamil within the Autosegmental-Metrical framework. It analyzes the rising F0 contours characteristic of declarative sentences and examines how interrogativity and focus are marked intonationally. It also describes collection of an intonational speech database designed to accommodate diglossia in Tamil.
An Autosegmental-Metrical analysis of Georgian intonation
Authors: Vicenik Chad , Jun Sun-Ah
Published: April 2014

This chapter proposes an intonational model of Georgian positing three prosodic units above the word, marked by a boundary tone. Additionally, it is claimed that previously described High tones on the antepenultimate syllable are a property of an Accentual Phrase, and not linked to a stressed syllable of the word.
The marked accentuation pattern of Curaçao Papiamentu
Authors: Remijsen Bert , Martis Farienne , Severing Ronnie
Published: April 2014

The variety of the Caribbean Creole language Papiamentu that is spoken on Curaçao has some lexical specification of tone, which combines with intonation. Certain sentence types (negations, wh-questions, most imperatives) are pronounced with a tonal pattern that replaces both the lexical specification of tone and the unmarked intonational pattern.
Complex intonation near the tonal isogloss in the Netherlands
Authors: Gussenhoven Carlos
Published: April 2014

The tonal dialect of Helden (Limburgish) has a low rise interrogative by the side of a high rise interrogative, but the dialect of Venlo employs this distinction to signal different lexical tones. To signal the lexical tone distinction, Helden’s rising interrogative contours have a contrastive pitch dip in the post-focal stretch. With four intonations contours, these two dialects, spoken in locations some 15 km apart on the north-western edge of the Franconian tonal area, have the largest number of intonation contours reported to date for these tonal dialects.