bluuebunny/crossref_metadata_2025 huggingface dataset:
Apples, Oranges, and the Burden of Proof – Putting Media Violence Findings Into Context
Authors: Warburton Wayne
Published: December 2013

In this comment on Elson and Ferguson (2013) , areas of agreement are noted in terms of the need to thoroughly and scientifically document the boundary conditions under which violent video games most impact players. However it is argued, in contrast to Elson and Ferguson, that violent media generally (and violent video games specifically) can and do increase the likelihood of aggressive behavior and desensitization to violence, and are linked to increases in aggressive attitudes and beliefs. It is also argued that research findings demonstrating these violent video game effects must be considered in terms of both the known impacts of other types of media on human thoughts and behavior, and well-documented psychological processes that have been empirically demonstrated to underlie the acquisition of all types of social behavior, not just aggression. To this end, evidence is provided that other types of media such as advertising are shown to clearly impact human psychology, and psychological mechanisms that potentially underlie media violence effects are discussed. It is further noted that there are no clearly evident reasons as to why violent video games should impact thoughts and behavior less than other media or be subject to different psychological processes. When the research evidence is considered in these contexts, it is concluded that the above-mentioned impacts of violent media exposure on human thought and behavior (including those of violent digital games) are demonstrated to two levels of proof – on the balance of probabilities and beyond reasonable doubt.
Understanding Variance in Pilot Performance Ratings
Authors: Mavin Timothy J. , Roth Wolff-Michael , Dekker Sidney
Published: December 2013

Two studies were designed to investigate how pilots of different rank evaluate flight-deck performance. In each study, the pilots were asked to assess sets of three different videotaped scenarios featuring pilots in a simulator exhibiting poor, average, and good performance. Study 1, which included 92 airline pilots of differing rank, was aimed at comparing how individuals rate performance. The subjects used a standardized assessment form, which included six criteria, each having a 5-point rating scale. Analysis of the first study revealed that there was considerable variance in the performance ratings between flight examiners, captains, and first officers. The second study was designed to better understand the variance. Eighteen pilots (six flight examiners, six captains, and six first officers) working in pairs evaluated performances, in a modified think-aloud protocol. The results showed that there were good reasons for the observed variances. The results are discussed in relation to inter-rater reliability.
Bradykinin Antagonist Counteracts the Acute Effect of Both Angiotensin-Converting Enzyme Inhibition and of Angiotensin Receptor Blockade on the Lower Limit of Autoregulation of Cerebral Blood Flow
Authors: Sigurdsson Sigurdur T , Paulson Olaf B , Høj Nielsen Arne , Strandgaard Svend
Published: December 2013

The lower limit of autoregulation of cerebral blood flow (CBF) can be modulated with both angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARB). The influence of bradykinin antagonism on ARB-induced changes was the subject of this study. CBF was measured in Sprague–Dawley rats with laser Doppler technique. The blood pressure was lowered by controlled bleeding. Six groups of rats were studied: a control group and five groups given drugs intravenously: an ACE inhibitor (enalaprilat), an ARB (candesartan), a bradykinin-2 receptor antagonist (Hoe 140), a combination of enalaprilat and Hoe 140, and a combination of candesartan and Hoe 140. In the control group, the lower limit of CBF autoregulation was 54±9 mm Hg (mean±s.d.), with enalaprilat it was 46±6, with candesartan 39±8, with Hoe 140 53±6, with enalaprilat/Hoe 140 52±6, and with candesartan/Hoe 140 50±7. Both enalaprilat and candesartan lowered the lower limit of autoregulation of CBF significantly. The bradykinin antagonist abolished not only the effect of the ACE inhibitor but surprisingly also the effect of the ARB on the lower limit of CBF autoregulation, the latter suggesting an effect on intravascular bradykinin.
Glycolysis and Oxidative Phosphorylation in Neurons and Astrocytes during Network Activity in Hippocampal Slices
Authors: Ivanov Anton I , Malkov Anton E , Waseem Tatsiana , Mukhtarov Marat , Buldakova Svetlana , Gubkina Olena , Zilberter Misha , Zilberter Yuri
Published: December 2013

Network activation triggers a significant energy metabolism increase in both neurons and astrocytes. Questions of the primary neuronal energy substrate (e.g., glucose vs. lactate) as well as the relative contributions of glycolysis and oxidative phosphorylation and their cellular origin (neurons vs. astrocytes) are still a matter of debates. Using simultaneous measurements of electrophysiological and metabolic parameters during synaptic stimulation in hippocampal slices from mature mice, we show that neurons and astrocytes use both glycolysis and oxidative phosphorylation to meet their energy demands. Supplementation or replacement of glucose in artificial cerebrospinal fluid (ACSF) with pyruvate or lactate strongly modifies parameters related to network activity-triggered energy metabolism. These effects are not induced by changes in ATP content, pHi, [Ca2+]i or accumulation of reactive oxygen species. Our results suggest that during network activation, a significant fraction of NAD(P)H response (its overshoot phase) corresponds to glycolysis and the changes in cytosolic NAD(P)H and mitochondrial FAD are coupled. Our data do not support the hypothesis of a preferential utilization of astrocyte-released lactate by neurons during network activation in slices—instead, we show that during such activity glucose is an effective energy substrate for both neurons and astrocytes.
Dye-sensitized solar cells based on multichromophoric supramolecular light-harvesting materials
Authors: Panda Dillip K. , Goodson Flynt S. , Ray Shuvasree , Saha Sourav
Published: December 2013

Dye-sensitized solar cells comprised of supramolecular light-harvesting zinc-phthalocyanine⋯peryleneimide dyads on TiO2 films generate photoelectricity throughout the 300–650 nm region with the power conversion efficiency reaching up to 2.3% and the incident-photon-to-current-efficiency up to 40% under one-sun conditions.
Crystallization behaviors of ZnxSb100−x thin films for ultralong data retention phase change memory applications
Authors: Chen Yimin , Wang Guoxiang , Shen Xiang , Xu Tiefeng , Wang R. P. , Wu Liangcai , Lu Yegang , Li Junjian , Dai Shixun , Nie Qiuhua
Published: December 2013

ZnSb films have higher crystallization temperature (~257 °C), larger crystalline activation energy (~5.63 eV), better 10 year-data-retention (~201 °C) and lower melting temperature (~500 °C).
Syntheses, structures, and properties of a series of 2D and 3D coordination polymers based on trifunctional pyridinedicarboxylate and different (bis)imidazole bridging ligands
Authors: Fan Liming , Zhang Xiutang , Zhang Wei , Ding Yuanshuai , Fan Weiliu , Sun Liming , Zhao Xian
Published: December 2013

Hydrothermal reactions based on two trifunctional pyridinedicarboxylate carboxylates and transitional metal cations in the presence of three (bis)imidazole bridging ligands afford ten 2D and 3D coordination polymers.
The effect of carrier gas humidity on the vaporization of laser-produced aerosols in inductively coupled plasmas
Authors: Flamigni Luca , Koch Joachim , Günther Detlef
Published: December 2013

The influence the carrier gas humidity has on the vaporization of laser-produced aerosols in inductively coupled plasmas is reported.
Development of CBAP-BPyne, a probe for γ-secretase and presenilinase
Authors: Gertsik Natalya , Ballard T. Eric , am Ende Christopher W. , Johnson Douglas S. , Li Yue-Ming
Published: December 2013

CBAP-BPyne, a dual presenilinase and γ-secretase clickable probe, provides a novel means to investigate the mechanism of endoproteolysis.
Rapid profiling of protein kinase inhibitors by quantitative proteomics
Authors: Golkowski Martin , Brigham Jennifer L. , Perera B. Gayani K. , Romano Guillermo S. , Maly Dustin J. , Ong Shao-En
Published: December 2013

Accelerating kinase inhibitor target profiling using a streamlined proteomic workflow and SILAC.
Simple metal/SiO2/Si planar photodetector utilizing leakage current flows through a SiO2 layer
Authors: Zu Baiyi , Lu Bin , Guo Yanan , Xu Tao , Dou Xincun
Published: December 2013

Metal/SiO2/Si planar photodetectors with superior performance were fabricated conveniently and cost-effectively utilizing leakage current flows through a SiO2 layer.
A combined molecular dynamics/micromechanics/finite element approach for multiscale constitutive modeling of nanocomposites with interface effects
Authors: Yang B. J. , Shin H. , Lee H. K. , Kim H.
Published: December 2013

We introduce a multiscale framework based on molecular dynamic (MD) simulation, micromechanics, and finite element method (FEM). A micromechanical model, which considers influences of the interface properties, nanoparticle (NP) size, and microcracks, is developed. Then, we perform MD simulations to characterize the mechanical properties of the nanocomposite system (silica/nylon 6) with varying volume fraction and size of NPs. By comparing the MD with micromechanics results, intrinsic physical properties at interfacial region are derived. Finally, we implement the developed model in the FEM code with the derived interfacial parameters, and predict the mechanical behavior of the nanocomposite at the macroscopic scale.
Measurements of light absorption efficiency in InSb nanowires
Authors: Jurgilaitis A. , Enquist H. , Harb M. , Dick K. A. , Borg B. M. , Nüske R. , Wernersson L.-E. , Larsson J.
Published: December 2013

We report on measurements of the light absorption efficiency of InSb nanowires. The absorbed 70 fs light pulse generates carriers, which equilibrate with the lattice via electron-phonon coupling. The increase in lattice temperature is manifested as a strain that can be measured with X-ray diffraction. The diffracted X-ray signal from the excited sample was measured using a streak camera. The amount of absorbed light was deduced by comparing X-ray diffraction measurements with simulations. It was found that 3.0(6)% of the radiation incident on the sample was absorbed by the nanowires, which cover 2.5% of the sample.
From sequences to polynomials and back, via operator orderings
Authors: Amdeberhan Tewodros , De Angelis Valerio , Dixit Atul , Moll Victor H. , Vignat Christophe
Published: December 2013

Bender and Dunne [“Polynomials and operator orderings,” J. Math. Phys. 29, 1727–1731 (1988)] showed that linear combinations of words qkpnqn−k, where p and q are subject to the relation qp − pq = ı, may be expressed as a polynomial in the symbol \documentclass[12pt]{minimal}\begin{document}$z = \frac{1}{2}(qp+pq)$\end{document}z=12(qp+pq). Relations between such polynomials and linear combinations of the transformed coefficients are explored. In particular, examples yielding orthogonal polynomials are provided.
Wavelet analysis of molecular dynamics: Efficient extraction of time-frequency information in ultrafast optical processes
Authors: Prior Javier , Castro Enrique , Chin Alex W. , Almeida Javier , Huelga Susana F. , Plenio Martin B.
Published: December 2013

New experimental techniques based on nonlinear ultrafast spectroscopies have been developed over the last few years, and have been demonstrated to provide powerful probes of quantum dynamics in different types of molecular aggregates, including both natural and artificial light harvesting complexes. Fourier transform-based spectroscopies have been particularly successful, yet “complete” spectral information normally necessitates the loss of all information on the temporal sequence of events in a signal. This information though is particularly important in transient or multi-stage processes, in which the spectral decomposition of the data evolves in time. By going through several examples of ultrafast quantum dynamics, we demonstrate that the use of wavelets provide an efficient and accurate way to simultaneously acquire both temporal and frequency information about a signal, and argue that this greatly aids the elucidation and interpretation of physical process responsible for non-stationary spectroscopic features, such as those encountered in coherent excitonic energy transport.
Some aspects of the orientational order distribution of flexible chains in a diblock mesophase
Authors: Lorthioir Cédric , Randriamahefa Solo , Deloche Bertrand
Published: December 2013

The segmental motions of flexible chains in the lamellar structure of a strongly segregated poly(styrene)-poly(dimethylsiloxane) (PS-PDMS) diblock were investigated over a time scale of a few tens of microseconds. 2H NMR experiments were performed on the PDMS block, selectively perdeuterated. Transverse relaxation measurements show that the main part of the PDMS repeat units display anisotropic reorientational motions within the diblock lamellae and such a segmental ordering essentially results from interchain steric repulsions. 2H double quantum-based experiments evidenced a non-uniform local stretching of PDMS chains and enabled the underlying distribution of the orientational order parameter to be determined quantitatively. Besides, a fraction of the PDMS chain segments, about 14%, were found to display isotropic – or nearly isotropic – reorientations, which could be assigned to repeat units located within a thin sublayer (about 1–2 nm) at the lamellae midplane, but also deeper in the lamellae, close to folded parts of the chains. These experimental results were confronted to theoretical descriptions of opposing polymer brushes and, in particular, to the strong-stretching theory (SST) including the entropic contribution of free chain ends.
Ground penetrating detection using miniaturized radar system based on solid state microwave sensor
Authors: Yao B. M. , Fu L. , Chen X. S. , Lu W. , Guo H. , Gui Y. S. , Hu C.-M.
Published: December 2013

We propose a solid-state-sensor-based miniaturized microwave radar technique, which allows a rapid microwave phase detection for continuous wave operation using a lock-in amplifier rather than using expensive and complicated instruments such as vector network analyzers. To demonstrate the capability of this sensor-based imaging technique, the miniaturized system has been used to detect embedded targets in sand by measuring the reflection for broadband microwaves. Using the reconstruction algorithm, the imaging of the embedded target with a diameter less than 5 cm buried in the sands with a depth of 5 cm or greater is clearly detected. Therefore, the sensor-based approach emerges as an innovative and cost-effective way for ground penetrating detection.
Ward identities and chiral anomalies for coupled fermionic chains
Authors: Costa L. C. , Ferraz A. , Mastropietro Vieri
Published: December 2013

Coupled fermionic chains are usually described by an effective model written in terms of bonding and anti-bonding fermionic fields with linear dispersion in the vicinities of the respective Fermi points. We derive for the first time exact Ward Identities (WI) for this model, proving the existence of chiral anomalies which verify the Adler-Bardeen non-renormalization property. Such WI are expected to play a crucial role in the understanding of the thermodynamic properties of the system. Our results are non-perturbative and are obtained analyzing Grassmann functional integrals by means of constructive quantum field theory methods.
Strain effect on the adsorption, diffusion, and molecular dissociation of hydrogen on Mg (0001) surface
Authors: Lei Huaping , Wang Caizhuang , Yao Yongxin , Wang Yangang , Hupalo Myron , McDougall Dan , Tringides Michael , Ho Kaiming
Published: December 2013

The adsorption, diffusion, and molecular dissociation of hydrogen on the biaxially strained Mg (0001) surface have been systematically investigated by the first principle calculations based on density functional theory. When the strain changes from the compressive to tensile state, the adsorption energy of H atom linearly increases while its diffusion barrier linearly decreases oppositely. The dissociation barrier of H2 molecule linearly reduces in the tensile strain region. Through the chemical bonding analysis including the charge density difference, the projected density of states and the Mulliken population, the mechanism of the strain effect on the adsorption of H atom and the dissociation of H2 molecule has been elucidated by an s-p charge transfer model. With the reduction of the orbital overlap between the surface Mg atoms upon the lattice expansion, the charge transfers from p to s states of Mg atoms, which enhances the hybridization of H s and Mg s orbitals. Therefore, the bonding interaction of H with Mg surface is strengthened and then the atomic diffusion and molecular dissociation barriers of hydrogen decrease accordingly. Our works will be helpful to understand and to estimate the influence of the lattice deformation on the performance of Mg-containing hydrogen storage materials.
A first-principles study of structural and elastic properties of bulk SrRuO3
Authors: Masys Š. , Jonauskas V.
Published: December 2013

We present a first-principles investigation of structural and elastic properties of experimentally observed phases of bulk SrRuO3 – namely orthorhombic, tetragonal, and cubic – by applying density functional theory (DFT) approximations. First, we focus our attention on the accuracy of calculated lattice constants in order to find out DFT approaches that best represent the crystalline structure of SrRuO3, since many important physical quantities crucially depend on change in volume. Next, we evaluate single-crystal elastic constants, macroscopic elastic parameters, and mechanical stability trying to at least partially compensate for the existing lack of information about these fundamental features of SrRuO3. Finally, we analyze the anomalous behavior of low-temperature orthorhombic phase under C44 related shear deformation. It turns out that at critical strain values the system exhibits a distinct deviation from the initial behavior which results in an isosymmetric phase transition. Moreover, under C44 related shear deformation tetragonal SrRuO3 becomes mechanically unstable raising an open question of what makes it experimentally observable at high temperatures.
Synthesis and mechanical behavior of nanoporous nanotwinned copper
Authors: Liu Ran , Zheng Shijian , Kevin Baldwin Jon , Kuthuru Mary , Mara Nathan , Antoniou Antonia
Published: December 2013

We synthesize nanoporous copper (NP Cu) through electrochemical dealloying of amorphous Cu0.41Si0.59 under compressive residual stress. Transmission Electron Microscopy reveals that struts are nanocrystalline with grain size equal to the strut thickness. Moreover, a significant population of twins with spacing ∼7 nm is present within each imaged grain. The hardness of this nanocrystalline, nanotwinned NP Cu is approximately one order of magnitude greater than reports on NP Cu in the literature. The yield strength of individual struts inferred through dimensional analysis is approximately an order of magnitude greater than bulk copper and compares well with other nanostructured copper systems.
Optimizing moderator dimensions for neutron scattering at the spallation neutron source
Authors: Zhao J. K. , Robertson J. L. , Herwig Kenneth W. , Gallmeier Franz X. , Riemer Bernard W.
Published: December 2013

In this work, we investigate the effect of neutron moderator dimensions on the performance of neutron scattering instruments at the Spallation Neutron Source (SNS). In a recent study of the planned second target station at the SNS facility, we have found that the dimensions of a moderator play a significant role in determining its surface brightness. A smaller moderator may be significantly brighter over a smaller viewing area. One of the immediate implications of this finding is that for modern neutron scattering instrument designs, moderator dimensions and brightness have to be incorporated as an integrated optimization parameter. Here, we establish a strategy of matching neutron scattering instruments with moderators using analytical and Monte Carlo techniques. In order to simplify our treatment, we group the instruments into two broad categories: those with natural collimation and those that use neutron guide systems. For instruments using natural collimation, the optimal moderator selection depends on the size of the moderator, the sample, and the moderator brightness. The desired beam divergence only plays a role in determining the distance between sample and moderator. For instruments using neutron optical systems, the smallest moderator available that is larger than the entrance dimension of the closest optical element will perform the best (assuming, as is the case here that smaller moderators are brighter).
Resonant stimulation of Raman scattering from single-crystal thiophene/phenylene co-oligomers
Authors: Yanagi Hisao , Marutani Yusuke , Matsuoka Naoki , Hiramatsu Toru , Ishizumi Atsushi , Sasaki Fumio , Hotta Shu
Published: December 2013

Amplified Raman scattering was observed from single crystals of thiophene/phenylene co-oligomers (TPCOs). Under ns-pulsed excitation, the TPCO crystals exhibited amplified spontaneous emission (ASE) at resonant absorption wavelengths. With increasing excitation wavelength to the 0-0 absorption edge, the stimulated resonant Raman peaks appeared both in the 0-1 and 0-2 ASE band regions. When the excitation wavelength coincided with the 0-1 ASE band energy, the Raman peaks selectively appeared in the 0-2 ASE band. Such unusual enhancement of the 0-2 Raman scattering was ascribed to resonant stimulation via vibronic coupling with electronic transitions in the uniaxially oriented TPCO molecules.
Theory of substrate, Zeeman, and electron-phonon interaction effects on the quantum capacitance in graphene
Authors: Tahir M. , Sabeeh K. , Shaukat A. , Schwingenschlögl U.
Published: December 2013

Since the discovery of graphene, a lot of interest has been attracted by the zeroth Landau level, which has no analog in the conventional two dimensional electron gas. Recently, lifting of the spin and valley degeneracies has been confirmed experimentally by capacitance measurements, while in transport experiments, this is difficult due to the scattering in the device. In this context, we model interaction effects on the quantum capacitance of graphene in the presence of a perpendicular magnetic field, finding good agreement with experiments. We demonstrate that the valley degeneracy is lifted by the substrate and by Kekule distortion, whereas the spin degeneracy is lifted by Zeeman interaction. The two cases can be distinguished by capacitance measurements.
Luminescent, dielectric, and ferroelectric properties of Pr doped Bi7Ti4NbO21 multifunctional ceramics
Authors: Zou Hua , Hui Xinwei , Wang Xusheng , Peng Dengfeng , Li Jun , Li Yanxia , Yao Xi
Published: December 2013

Pr doped Bi7Ti4NbO21 (BTN) multifunctional ceramics were prepared by a conventional sintering technique and their luminescent, dielectric, and ferroelectric properties were investigated. The X-ray diffraction data showed that the samples were single phase, and the scanning electron microscopy image indicated that the ceramics had flake-like grains with uniform thickness. The red emission was observed under the ultraviolet and blue light excitation at room temperature. The thermal quench of luminescence was measured and the result indicated that Pr doped BTN ceramics might be potentially applied in luminescent probes and temperature sensors. With the increasing Pr3+ content, the intensity of the photoluminescence increased initially and then decreased due to concentration quenching; The Curie temperature Tc was slightly shifted to the lower temperature; the ferroelectric properties was almost unchanged by doping. As a new multifunctional material, the Pr doped BTN ceramics could be used for a wide range of application, such as integrated electro-optical devices.
Nanoscale compositional banding in binary thin films produced by ion-assisted deposition
Authors: Mark Bradley R.
Published: December 2013

During the ion-assisted deposition of a binary material, the ion beam can induce the formation of nanoscale ripples on the surface of the growing thin film and compositional banding within its bulk. We demonstrate that this remains true even if the curvature dependence of the sputter yields and ballistic mass redistribution are negligible, and the two atomic species are completely miscible. The concentration of the species with the lower of the two sputter yields is higher at the crests of the ripples than at their troughs. Depending on the angles of incidence of the two atomic species, the incident flux of atoms with the higher sputter yield can either stabilize or destabilize the initially flat surface of the thin film.
The “accumulation effect” of positrons in the stack of foils, detected by measurements of the positron implantation profile
Authors: Dryzek Jerzy , Siemek Krzysztof
Published: December 2013

The profiles of positrons implanted from the radioactive source 22Na into a stack of foils and plates are the subject of our experimental and theoretical studies. The measurements were performed using the depth scanning of positron implantation profile method, and the theoretical calculations using the phenomenological multi-scattering model (MSM). Several stacks consisting of silver, gold and aluminum foils, and titanium and germanium plates were investigated. We notice that the MSM describes well the experimental profiles; however when the stack consisting of silver and gold foils, the backscattering and linear absorption coefficients differ significantly from those reported in the literature. We suggest the energy dependency of the backscattering coefficient for silver and gold. In the stacks which comprise titanium and germanium plates, there were observed the features, which indicate the presence of the “accumulation effect” in the experimental implantation profile. This effect was previously detected in implantation profiles in Monte Carlo simulations using the GEANT4 tool kit, and it consists in higher localization of positrons close the interface. We suppose that this effect can be essential for positron annihilation in any heterogeneous materials.
Propagation of surface waves on a semi-bounded quantum magnetized collisional plasma
Authors: Niknam A. R. , Taheri Boroujeni S. , Khorashadizadeh S. M.
Published: December 2013

The propagation of surface waves on a semi-bounded quantum plasma in the presence of the external magnetic field and collisional effects is investigated by using quantum magnetohydrodynamics model. A general analytical expression for the dispersion relation of surface waves is obtained by considering the boundary conditions. It is shown that, in some special cases, the obtained dispersion relation reduces to the results reported in previous works. It is also indicated that the quantum, external magnetic field and collisional effects can facilitate the propagation of surface waves on a semi-bounded plasma. In addition, it is found that the growth rate of the surface wave instability is enhanced by increasing the collision frequency and plasmonic parameter.
Comparative thermal conductivity measurement of chemical vapor deposition grown graphene supported on substrate
Authors: Sidorov Anton N. , Benjamin Daniel K. , Foy Christopher
Published: December 2013

We develop a comparative thermal conductivity measurement technique based on miniature differential thermocouples and measure the temperature dependence of the thermal conductivity of chemical vapor deposition grown graphene supported on glass or SiO2 substrate in the temperature range of 180–420 K. For all 28 investigated samples, the obtained room temperature values of the thermal conductivity are bounded between 1800 and 2200 W/m K. Compared with other techniques, we find that a significant improvement in accuracy of our measurements is because of the absence of chemical doping/contamination from micro-fabrication procedures. Our results are confirmed using scanning thermal microscopy.
Voltage dependent displacement current as a tool to measure the vacuum level shift caused by self-assembled monolayers on aluminum oxide
Authors: Nyman Mathias , Sandberg Oskar , Martínez Hardigree Josué F. , Kola Srinivas , Katz Howard E. , Österbacka Ronald
Published: December 2013

We present charge extraction by a linearly increasing voltage measurements on diodes based on an n-channel naphthalenetetracarboxylic acid diimide semiconductor and an aluminum oxide blocking layer. Results show a large displacement current (roughly 15 times that expected from the geometrical capacitance), which we associate with trap filling in the oxide. The trap density is calculated to be on the order of 1019 cm−3, in agreement with preceding work. We present a way of using the displacement current as a tool for probing the vacuum level shift caused by modifying the oxide surface with self-assembled monolayers in operating devices.
Scalable evaluation of platelet aggregation by the degree of blood migration
Authors: Song Suk-Heung , Lim Chae-Seung , Shin Sehyun
Published: December 2013

Platelet aggregation plays a key role in vascular thrombosis. Antiplatelet drug therapy is commonly used for the prevention of abnormal platelet aggregation. So, measuring platelet aggregation function is critically important in clinical field. Here, we introduce a scalable evaluation method of platelet aggregation measured with the degree of blood migration through microchannel in a microfluidic chip. Unlike conventional methods that require expertise with system physics to operate devices, our approach is using microfluidics system, which requires only a syringe vacuum. The scalable migration factors, migration distance and touchdown time, are capable of distinguishing various antiplatelet drug effects under microfluidics and would be effective for the quick and easy evaluation of quantitative platelet aggregation.
A micrometer-size movable light emitting area in a resonant tunneling light emitting diode
Authors: Pettinari G. , Balakrishnan N. , Makarovsky O. , Campion R. P. , Polimeni A. , Capizzi M. , Patanè A.
Published: December 2013

We report on the fabrication of a micrometer-size movable light emitting area in a GaAs/AlAs quantum well resonant tunneling p-i-n diode. The spatial position of the micrometer-size light emitting area shifts linearly with increasing applied bias, up to 30 μm for a bias increment of 0.2 V. Also, the simultaneous resonant tunneling injection of both electrons and holes into the quantum well states is achieved at specific positions of the diode, thus resulting in a tenfold increase of the electroluminescence intensity.
Limit for thermal transport reduction in Si nanowires with nanoengineered corrugations
Authors: Sullivan Sean E. , Lin Keng-Hua , Avdoshenko Stanislav , Strachan Alejandro
Published: December 2013

Non-equilibrium molecular dynamics simulations reveal that the thermal conductance of Si nanowires with periodic corrugations is lower than that of smooth wires with cross-sections equivalent to the constricted portions. This reduction in conductance is up to 30% and tends to plateau with increasing corrugation height. Spatially resolved temperature and heat current maps provide a microscopic understanding of this effect; we find that 80% of the heat current is carried through the constricted area even for high-amplitude corrugations. More importantly, we show that temperature gradient inversion and heat current vortices at the ridge peaks establish fundamental limits on maximum conductance reduction.
Observation of thermal Barkhausen effect in ferroelectric films of poly(vinylidene fluoride/trifluoroethylene) copolymer
Authors: Mai Manfang , Kliem Herbert
Published: December 2013

Thermal Barkhausen effect is observed in poly(vinylidene fluoride/trifluoroethylene) [P(VDF-TrFE)] copolymer films for the first time. Barkhausen pulses arise at phase transition close to the Curie point during both heating and cooling without an external electric field. Three types of current pulses are obtained associated with nucleation and domain wall motion. The switched dipole number under one pulse is generally much less than 1% of the sample's total dipoles.
Field-driven sense elements for chirality-dependent domain wall detection and storage
Authors: Bowden S. R. , Unguris J.
Published: December 2013

A method for locally sensing and storing data of transverse domain wall chirality in planar nanowire logic and memory systems is presented. Patterned elements, in close proximity to the nanowires, respond to the asymmetry in the stray field from the domain wall to produce a chirality-dependent response. When a bias field is applied, a stray field-assisted reversal of the element magnetization results in a reversed remanent state, measurable by scanning electron microscopy with polarization analysis (SEMPA). The elements are designed as triangles with tips pointing toward the nanowire, allowing the shape anisotropy to be dominated by the base but having a portion with lower volume and lower energy barrier closest to the domain wall. Micromagnetic modeling assists in the design of the nanowire-triangle systems and experiments using SEMPA confirm the importance of aspect ratio and spacing given a constant bias field magnitude.
Integrated ultrasonic particle positioning and low excitation light fluorescence imaging
Authors: Bernassau A. L. , Al-Rawhani M. , Beeley J. , Cumming D. R. S.
Published: December 2013

A compact hybrid system has been developed to position and detect fluorescent micro-particles by combining a Single Photon Avalanche Diode (SPAD) imager with an acoustic manipulator. The detector comprises a SPAD array, light-emitting diode (LED), lenses, and optical filters. The acoustic device is formed of multiple transducers surrounding an octagonal cavity. By stimulating pairs of transducers simultaneously, an acoustic landscape is created causing fluorescent micro-particles to agglomerate into lines. The fluorescent pattern is excited by a low power LED and detected by the SPAD imager. Our technique combines particle manipulation and visualization in a compact, low power, portable setup.
Coupled double-layer Fano resonance photonic crystal filters with lattice-displacement
Authors: Shuai Yichen , Zhao Deyin , Singh Chadha Arvinder , Seo Jung-Hun , Yang Hongjun , Fan Shanhui , Ma Zhenqiang , Zhou Weidong
Published: December 2013

We present here ultra-compact high-Q Fano resonance filters with displaced lattices between two coupled photonic crystal slabs, fabricated with crystalline silicon nanomembrane transfer printing and aligned e-beam lithography techniques. Theoretically, with the control of lattice displacement between two coupled photonic crystal slabs layers, optical filter Q factors can approach 211 000 000 for the design considered here. Experimentally, Q factors up to 80 000 have been demonstrated for a filter design with target Q factor of 130 000.
Thermal fluctuations and critical behavior in a magnetized, anisotropic plasma
Authors: Hazeltine R. D. , Mahajan S. M.
Published: December 2013

Thermal fluctuations in a magnetized, anisotropic plasma are studied by applying standard methods, based on the Einstein rule, to the known thermodynamic potential of the system. It is found in particular that magnetic fluctuations become critical when the anisotropy p∥−p⊥ changes sign. By examining the critical region, additional insight on the equations of state for near-critical anisotropic plasma is obtained.
Electronic excitation as a mode of heat dissipation in laser-driven cluster plasmas
Authors: Rajeev R. , Rishad K. P. M. , Madhu Trivikram T. , Krishnamurthy M.
Published: December 2013

Electrons streaming out of laser plasma are known for non-local heat transport and energy deposition by the ionization wave. At 100 eV electron temperature, since the electronic excitation cross section is comparable to that of ionization for Ar and CO2, a non-local excitation wave akin to the ionization wave is envisaged where energy deposition in excitations forms a excited cluster sheath beyond the laser focus. Here, we show that nano-cluster systems have the right parameters to form such an exciton sheath and experimentally demonstrate this via charge transfer reactions.
A C70-carbon nanotube complex for bulk heterojunction photovoltaic cells
Authors: Lau Xinbo C. , Wang Zhiqian , Mitra Somenath
Published: December 2013

A C70 fullerene-multi-walled carbon nanotube (C70-CNT) complex has been used as a component of the photoactive layer in a bulk heterojunction photovoltaic cell. As compared to a control device with only C70, the addition of CNTs led to improvements in short circuit current density (Jsc), open circuit voltage (Voc), and power conversion efficiency by 31.8, 17.5, and 69.5%, respectively. This device takes advantage of both the electron accepting feature of C70 and the high electron transport capability of CNTs. These results indicate that C70 decorated CNT is a promising additive for performance enhancement of polymer photovoltaic cells.
On quantitative analysis of interband recombination dynamics: Theory and application to bulk ZnO
Authors: Lettieri S. , Capello V. , Santamaria L. , Maddalena P.
Published: December 2013

The issue of the quantitative analysis of time-resolved photoluminescence experiments is addressed by developing and describing two approaches for determination of unimolecular lifetime, bimolecular recombination coefficient, and equilibrium free-carrier concentration, based on a quite general second-order expression of the electron-hole recombination rate. Application to the case of band-edge emission of ZnO single crystals is reported, evidencing the signature of sub-nanosecond second-order recombination dynamics for optical transitions close to the interband excitation edge. The resulting findings are in good agreement with the model prediction and further confirm the presence, formerly evidenced in literature by non-optical methods, of near-surface conductive layers in ZnO crystals with sheet charge densities of about 3–5×1013 cm−2.
Near-field microwave microscopy of high-κ oxides grown on graphene with an organic seeding layer
Authors: Tselev Alexander , Sangwan Vinod K. , Jariwala Deep , Marks Tobin J. , Lauhon Lincoln J. , Hersam Mark C. , Kalinin Sergei V.
Published: December 2013

Near-field scanning microwave microscopy (SMM) is used for non-destructive nanoscale characterization of Al2O3 and HfO2 films grown on epitaxial graphene on SiC by atomic layer deposition using a self-assembled perylene-3,4,9,10-tetracarboxylic dianhydride seeding layer. SMM allows imaging of buried inhomogeneities in the dielectric layer with a spatial resolution close to 100 nm. The results indicate that, while topographic features on the substrate surface cannot be eliminated as possible sites of defect nucleation, the use of a vertically heterogeneous Al2O3/HfO2 stack suppresses formation of large outgrowth defects in the oxide film, ultimately improving lateral uniformity of the dielectric film.
In-situ x-ray diffraction study of the growth of highly strained epitaxial BaTiO3 thin films
Authors: Sinsheimer J. , Callori S. J. , Ziegler B. , Bein B. , Chinta P. V. , Ashrafi A. , Headrick R. L. , Dawber M.
Published: December 2013

In-situ synchrotron x-ray diffraction was performed during the growth of BaTiO3 thin films on SrTiO3 substrates using both off-axis RF magnetron sputtering and pulsed laser deposition techniques. It was found that the films were ferroelectric during the growth process, and the presence or absence of a bottom SrRuO3 electrode played an important role in the growth of the films. Pulsed laser deposited films on SrRuO3 displayed an anomalously high tetragonality and unit volume, which may be connected to the previously predicted negative pressure phase of BaTiO3.
Experimentally observed field–gas interaction in intense optical lattices
Authors: Graul Jacob S. , Cornella Barry M. , Ketsdever Andrew D. , Lilly Taylor C. , Shneider Mikhail N.
Published: December 2013

When a gas perturbed by a laser interference pattern, an optical lattice, exhibits a periodic modulation of its refractive index, strong Bragg diffraction of the perturbing light can occur. This scattering reduces the field's ability to further manipulate the gas. Experimental observations of Bragg scattering, evidence of a two-way coupling, are compared to the evolution of the light fields calculated by solutions to the wave equation. Comparison indicates momentum deposition as a prime contributor to the shape of the scattering function vs. lattice velocity, a rationale further supported through additional direct simulation Monte Carlo simulation.
PI3K regulates MEK/ERK signaling in breast cancer via the Rac-GEF, P-Rex1
Authors: Ebi Hiromichi , Costa Carlotta , Faber Anthony C. , Nishtala Madhuri , Kotani Hiroshi , Juric Dejan , Della Pelle Patricia , Song Youngchul , Yano Seiji , Mino-Kenudson Mari , Benes Cyril H. , Engelman Jeffrey A.
Published: December 2013

Significance

Genetic alterations targeting the PI3K pathway are highly prevalent in breast cancers. Although breast cancers harboringPIK3CAmutation andHER2amplification have enhanced sensitivity to PI3K inhibitors, the mechanism underlying this sensitivity is unknown. This study shows that PI3K inhibitors suppress MEK/ERK pathway in these cancers, and inhibition of both AKT and ERK pathways is necessary for maximal antitumoral activity. We elucidate a unique mechanistic link between PI3K and ERK via PI3K-dependent regulation of P-Rex1, which in turn regulates the Rac1/PAK/c-RAF/MEK/ERK pathway. Importantly, expression levels of the Rac-GEF, P-Rex1, correlate with sensitivity to PI3K inhibitors among these breast cancer cell lines, indicating its potential utility as a biomarker to identify cancers that will respond to PI3K inhibitors.
Cholinergic left-right asymmetry in the habenulo-interpeduncular pathway
Authors: Hong Elim , Santhakumar Kirankumar , Akitake Courtney A. , Ahn Sang Jung , Thisse Christine , Thisse Bernard , Wyart Claire , Mangin Jean-Marie , Halpern Marnie E.
Published: December 2013

Significance

The forebrain habenular nuclei (Hb) and their connections to the midbrain interpeduncular nucleus (IPN) have emerged as a valuable model to study left-right differences in the zebrafish brain. However, whether this pathway is enriched in the neurotransmitter acetylcholine and involved in nicotine addiction as in mammals is unresolved. We discovered a duplicated cholinergic gene locus that is predominantly expressed in the right Hb at larval stages. Through electrophysiology and pharmacology, we show that this asymmetrical cholinergic pathway is functional. Moreover, specific nicotinic acetylcholine receptor subunits localize to the same subregions of the IPN that are activated by exposure of adults to nicotine. Our study firmly establishes the zebrafish as a valid model to study how Hb-IPN circuitry influences nicotine addiction.
Forage Fish Interactions: a symposium on “Creating the tools for ecosystem-based management of marine resources”
Authors: Peck Myron A. , Neuenfeldt Stefan , Essington Timothy E. , Trenkel Verena M. , Takasuka Akinori , Gislason Henrik , Dickey-Collas Mark , Andersen Ken H. , Ravn-Jonsen Lars , Vestergaard Niels , Kvamsdal Sturla F. , Gårdmark Anna , Link Jason , Rice Jake C.
Published: December 2013

Peck, M. A., Neuenfeldt, S., Essington, T. E., Trenkel, V. M., Takasuka, A., Gislason, H., Dickey-Collas, M., Andersen, K. H., Ravn-Jonsen, L., Vestergaard, N., Kvamsdal, S., Gårdmark, A., Link, J., and Rice, J. Forage Fish Interactions: a symposium on “Creating the tools for ecosystem-based management of marine resources”. – ICES Journal of Marine Science, 71: . Forage fish (FF) have a unique position within marine foodwebs and the development of sustainable harvest strategies for FF will be a critical step in advancing and implementing the broader, ecosystem-based management of marine systems. In all, 70 scientists from 16 nations gathered for a symposium on 12–14 November 2012 that was designed to address three key questions regarding the effective management of FF and their ecosystems: (i) how do environmental factors and predator–prey interactions drive the productivity and distribution of FF stocks across ecosystems worldwide, (ii) what are the economic and ecological costs and benefits of different FF management strategies, and (iii) do commonalities exist across ecosystems in terms of the effective management of FF exploitation?
Effect of Germination and UV‐C Radiation on the Accumulation of Flavonoids and Saponins in Black Bean Seed Coats
Authors: Guajardo‐Flores Daniel , Serna‐Guerrero Delia , Serna‐Saldívar Sergio O. , Jacobo‐Velázquez Daniel A.
Published: December 2013

In the present study, we evaluated UV‐C radiation and germination treatments as an approach to increase the concentration of bioactive molecules in black bean seed coats. Black beans were germinated for 20 h under UV‐C radiation. Germination rate was higher in seeds radiated with UV‐C light compared with the control (nonirradiated seeds). Flavonoid content was increased twofold in seed coats of beans germinated for 10 h under UV‐C compared with the control. Quercetin‐3O‐glucoside was the major flavonoid identified in stressed seed coats. Furthermore, the application of UV‐C radiation during germination increased the content of soyasaponin Af, Ba, and αg, and it induced the de novo biosynthesis of soyasaponins (phaseoside I, soyasaponin deacetyl Af, and soyasaponin deactyl Ah) not present in the control. Germination of black beans under UV‐C radiation was an effective and simple approach to increase the concentration of bioactive molecules in black bean seed coats.
Translocation and Functional Analysis ofPseudomonas savastanoipv.savastanoiNCPPB 3335 Type III Secretion System Effectors Reveals Two Novel Effector Families of thePseudomonas syringaeComplex
Authors: Matas Isabel M. , Castañeda-Ojeda M. Pilar , Aragón Isabel M. , Antúnez-Lamas María , Murillo Jesús , Rodríguez-Palenzuela Pablo , López-Solanilla Emilia , Ramos Cayo
Published: December 2013

Pseudomonas savastanoi pv. savastanoi NCPPB 3335 causes olive knot disease and is a model pathogen for exploring bacterial infection of woody hosts. The type III secretion system (T3SS) effector repertoire of this strain includes 31 effector candidates plus two novel candidates identified in this study which have not been reported to translocate into plant cells. In this work, we demonstrate the delivery of seven NCPPB 3335 effectors into Nicotiana tabacum leaves, including three proteins from two novel families of the P. syringae complex effector super-repertoire (HopBK and HopBL), one of which comprises two proteins (HopBL1 and HopBL2) that harbor a SUMO protease domain. When delivered by P. fluorescens heterologously expressing a P. syringae T3SS, all seven effectors were found to suppress the production of defense-associated reactive oxygen species. Moreover, six of these effectors, including the truncated versions of HopAA1 and HopAZ1 encoded by NCPPB 3335, suppressed callose deposition. The expression of HopAZ1 and HopBL1 by functionally effectorless P. syringae pv. tomato DC3000D28E inhibited the hypersensitive response in tobacco and, additionally, expression of HopBL2 by this strain significantly increased its competitiveness in N. benthamiana. DNA sequences encoding HopBL1 and HopBL2 were uniquely detected in a collection of 31 P. savastanoi pv. savastanoi strains and other P. syringae strains isolated from woody hosts, suggesting a relevant role of these two effectors in bacterial interactions with olive and other woody plants.