bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetized electron emission from a small spherical dust grain in fusion related plasmas
Authors: Autricque A. , Fedorczak N. , Khrapak S. A. , Couëdel L. , Klumov B. , Arnas C. , Ning N. , Layet J.-M. , Grisolia C.
Published: December 2017

The effect of magnetic field on the electron emission yield from a small spherical dust grain immersed in a plasma is investigated. It is demonstrated that, due to their gyromotion, some electrons can be promptly recollected on the grain's surface, which can reduce the emitted electron flux. The consequences are discussed mainly in the context of fusion-related applications, where the dust floating potential can be significantly reduced when positive while the dust lifetime remains weakly affected. In particular, we suggest that this effect should be included in the codes used to model the dust transport in tokamaks.
Comparative study of organic transistors with different graphene electrodes fabricated using a simple patterning method
Authors: Kang Narae , Smith Christian W. , Ishigami Masa , Khondaker Saiful I.
Published: December 2017

The performance of organic field-effect transistors (OFETs) can be greatly limited due to the inefficient charge injection caused by the large interfacial barrier at the metal/organic semiconductor interface. To improve this, two-dimensional graphene films have been suggested as alternative electrode materials; however, a comparative study of OFET performances using different types of graphene electrodes has not been systematically investigated. Here, we present a comparative study on the performance of pentacene OFETs using chemical vapor deposition (CVD) grown graphene and reduced graphene oxide (RGO) as electrodes. The large area electrodes were patterned using a simple and environmentally benign patterning technique. Although both the CVD graphene and RGO electrodes showed enhanced device performance compared to metal electrodes, we found the maximum performance enhancement from CVD grown graphene electrodes. Our study suggests that, in addition to the strong π-π interaction at the graphene/organic interface, the higher conductivity of the electrodes also plays an important role in the performance of OFETs.
High-intensity discharge lamp and Duffing oscillator—Similarities and differences
Authors: Baumann Bernd , Schwieger Joerg , Stein Ulrich , Hallerberg Sarah , Wolff Marcus
Published: December 2017

The processes inside the arc tube of high-intensity discharge lamps are investigated using finite element simulations. The behavior of the gas mixture inside the arc tube is governed by differential equations describing mass, energy, and charge conservation, as well as the Helmholtz equation for the acoustic pressure and the Reynolds equations for the flow driven by buoyancy and Reynolds stresses. The model is highly nonlinear and requires a recursion procedure to account for the impact of acoustic streaming on the temperature and other fields. The investigations reveal the presence of a hysteresis and the corresponding jump phenomenon, quite similar to a Duffing oscillator. The similarities and, in particular, the differences of the nonlinear behavior of the high-intensity discharge lamp to that of a Duffing oscillator are discussed. For large amplitudes, the high-intensity discharge lamp exhibits a stiffening effect in contrast to the Duffing oscillator. It is speculated on how the stiffening might affect hysteresis suppression.
Thermal imitators with single directional invisibility
Authors: Wang Ruizhe , Xu Liujun , Huang Jiping
Published: December 2017

Thermal metamaterials have been intensively studied during the past years to achieve the long-standing dream of invisibility, illusion, and other inconceivable thermal phenomena. However, many thermal metamaterials can only exhibit omnidirectional thermal response, which take on the distinct feature of geometrical isotropy. In this work, we theoretically design and experimentally fabricate a pair of thermal imitators by applying geometrical anisotropy provided by elliptical/ellipsoidal particles and layered structures. This pair of thermal imitators possesses thermal invisibility in one direction, while having thermal opacity in other directions. This work may open a gate in designing direction-dependent thermal metamaterials.
Photo-induced persistent enhancement of dielectric permittivity in Zn:BaAl2O4
Authors: Nagai Takayuki , Yamada Yasusei , Tanabe Kenji , Terasaki Ichiro , Taniguchi Hiroki
Published: December 2017

Photo-induced persistent enhancement of dielectric permittivity has been demonstrated in Ba(Al0.97Zn0.03)2O4−δ (BAZ) with a stuffed-tridymite-type structure under photo-irradiation with an energy of 3.4 eV (365 nm). The dielectric permittivity is enhanced by more than 20% and shows a weak frequency dependency. The dielectric loss (tanδ) shows only a slight increment for frequencies up to 1 MHz, indicating that the incremental change in dielectric permittivity of BAZ is not caused by photoconduction. This enhancement persists on termination of photo-irradiation. The results of this study suggest that the origin of the enhancement of dielectric permittivity is related to the dielectric response of the photo-excited dipole moments, which are composed of photo-excited electrons trapped in in-gap states and photo-excited holes generated in the valence band maximum. These findings shed light on the development of devices that can control dielectric properties by photo-irradiation.
Ab initio simulations of bond breaking in sulfur crosslinked isoprene oligomer units
Authors: Gehrke Sascha , Alznauer Hans Tobias , Karimi-Varzaneh Hossein Ali , Becker Jörg August
Published: December 2017

Sulfur crosslinked polyisoprene (rubber) is used in important material components for a number of technical tasks (e.g., in tires and sealings). If mechanical stress, like tension or shear, is applied on these material components, the sulfur crosslinks suffer from homolytic bond breaking. In this work, we have simulated the bond breaking mechanism of sulfur crosslinks between polyisoprene chains using Car-Parrinello molecular dynamic simulations and investigated the maximum forces which can be resisted by the crosslinks. Small model systems with crosslinks formed by chains of N = 1 to N = 6 sulfur atoms have been simulated with the slow growth-technique, known from the literature. The maximum force can be thereby determined from the calculated energies as a function of strain (elongation). The stability of the crosslink under strain is quantified in terms of the maximum force that can be resisted by the system before the crosslink breaks. As shown by our simulations, this maximum force decreases with the sulfur crosslink length N in a step like manner. Our findings indicate that in bridges with N = 1, 2, and 3 sulfur atoms predominantly, carbon-sulfur bonds break, while in crosslinks with N > 3, the breaking of a sulfur-sulfur bond is the dominant failure mechanism. The results are explained within a simple chemical bond model, which describes how the delocalization of the electrons in the generated radicals can lower their electronic energy and decrease the activation barriers. It is described which of the double bonds in the isoprene units are involved in the mechanochemistry of crosslinked rubber.
Blocking germanium diffusion inside silicon dioxide using a co-implanted silicon barrier
Authors: Barba D. , Wang C. , Nélis A. , Terwagne G. , Rosei F.
Published: December 2017

We investigate the effect of co-implanting a silicon sublayer on the thermal diffusion of germanium ions implanted into SiO2 and the growth of Ge nanocrystals (Ge-ncs). High-resolution imaging obtained by transmission electron microscopy and energy dispersive spectroscopy measurements supported by Monte-Carlo calculations shows that the Si-enriched region acts as a diffusion barrier for Ge atoms. This barrier prevents Ge outgassing during thermal annealing at 1100 °C. Both the localization and the reduced size of Ge-ncs formed within the sample region co-implanted with Si are observed, as well as the nucleation of mixed Ge/Si nanocrystals containing structural point defects and stacking faults. Although it was found that the Si co-implantation affects the crystallinity of the formed Ge-ncs, this technique can be implemented to produce size-selective and depth-ordered nanostructured systems by controlling the spatial distribution of diffusing Ge. We illustrate this feature for Ge-ncs embedded within a single SiO2 monolayer, whose diameters were gradually increased from 1 nm to 5 nm over a depth of 100 nm.
Autophoretic locomotion in weakly viscoelastic fluids at finite Péclet number
Authors: Natale Giovanniantonio , Datt Charu , Hatzikiriakos Savvas G. , Elfring Gwynn J.
Published: December 2017

In this work, we numerically investigate the dynamics of a self-propelling autophoretic Janus particle in a weakly viscoelastic fluid. The self-propulsion is achieved by an asymmetry in the properties of the surface of the Janus particle that drives a surface slip velocity and bulk flow. Here we investigate the effect of viscoelasticity on this advection-diffusion problem over a range of Péclet and Damköhler numbers. Particles are found to swim faster, or slower, in viscoelastic fluids, and we show how reaction and diffusion rates affect the viscoelastic stresses that lead to changes in propulsion.
Maskless regrowth of GaN for trenched devices by MOCVD
Authors: Agarwal Anchal , Koksaldi Onur , Gupta Chirag , Keller Stacia , Mishra Umesh K.
Published: December 2017

Blanket regrowth studies were performed on GaN trenches with varying widths and optimized for two types of devices—those that required the profile of the trench to be maintained and those that required the complete filling of trenches, i.e., a planar surface after regrowth. Low temperature Al0.22Ga0.78N growth was optimized and used as the marker layer for SEM. GaN deposition at a medium temperature of 950 °C and using N2 as carrier gas resulted primarily in growth on the (0001) plane, while the growth on the sidewalls was governed by the formation of slow growing semi-polar planes. This gave a conformal profile to the regrown GaN—useful for regrown GaN interlayer based vertical trench MOSFETs. In contrast, high temperature (1150 °C) growth in H2 resulted in high lateral growth rates. The planar surface was achieved under these conditions—a very promising result for CAVET-type devices.
Effect of Cr-N codoping on structural phase transition, Raman modes, and optical properties of TiO2 nanoparticles
Authors: Hassnain Jaffari G. , Tahir Adnan , Ali Naveed Zafar , Ali Awais , Qurashi Umar S.
Published: December 2017

Noncompensated cation-anion codoping in TiO2 nanoparticles has been achieved by a chemical synthesis route. Significant reduction in the optical bandgap and enhancement in the absorption of visible light have been observed. Structural phase transformation has been tracked in detail as a function of doping and heat treatment temperature. Anatase to rutile phase transition temperature for doped samples was higher in comparison to the pure TiO2 nanoparticles. Nitrogen and chromium addition increases the phase transformation barrier, where the effect of the former dopant is of more significance. The Raman results showed an increase in the oxygen content with higher post annealing temperatures. With Cr incorporation, the peak associated with the Eg mode has been found to shift towards a higher wave number, while with nitrogen incorporation, the shift was towards a lower wave number. A decrease in reflectance with N co-doping for all samples, irrespective of phase and annealing temperatures, has been observed. In compositions with nitrogen of the same content, bandgap reduction was higher in the rutile phase in comparison to the anatase phase. In general, overall results revealed that with a higher loading fraction of ammonia, the N content increases, while Cr addition prevents nitrogen loss even up to high post annealing temperatures, i.e., 850 °C.
A strategy for high specific power pyroelectric energy harvesting from a fluid source
Authors: Maheux E. , Hrebtov M. Yu. , Sukhorukov G. , Kozyulin N. N. , Bobrov M. S. , Dobroselsky K. G. , Chikishev L. M. , Dulin V. M. , Yudin P. V.
Published: December 2017

Conversion of waste heat into usable electricity is now one of the important strategies for saving natural resources and minimizing impact on the environment. In contrast to Seebeck devices, utilizing a temperature gradient, pyroelectric scavengers use temporal temperature oscillations. Here, optimal strategies for pyroelectric energy harvesting are theoretically investigated from the point of view of non-stationary heat exchange for the application-relevant case of harvesting with a pyroelectric lamella from a fluid heat source. It is shown that for a fixed lamella thickness by choosing appropriate phase shift between the temperature oscillations and the voltage on the pyroelectric lamella, one can effectively operate at high frequencies and achieve a two to three-fold increase in specific power with respect to the classical Olsen cycle. A further increase in specific power is achieved by thinning down the lamella. For devices with a thickness down to a few hundreds of nanometers, specific power linearly increases with the inverse thickness. Further scaling down of the device is hampered with the heat exchange in the boundary layer. Our simulations for a representative pyroelectric Pb(Zr0,5Ti0,5)O3 predict harvestable powers of the order of kW/kg for a device with a thickness in the range from 100 nm to 1 μm, operating at hundreds of Hz.
Structural modification through pressurized sub-Tg annealing of metallic glasses
Authors: Foroughi A. , Ashuri H. , Tavakoli R. , Stoica M. , Şopu D. , Eckert J.
Published: December 2017

The atomic structure of metallic glasses (MGs) plays an important role in their physical and mechanical properties. Numerous molecular dynamics (MD) simulations have been performed to reveal the structure of MGs at the atomic scale. However, the cooling rates utilized in most of the MD simulations (usually on the order of 109–1012 K/s) are too high to allow the structure to relax into the actual structures. In this study, we performed long-term pressurized sub-Tg annealing for up to 1 μs using MD simulation to systematically study the structure evolution of Cu50Zr50 MG. We find that from relaxation to rejuvenation, structural excitation of MGs and transition during sub-Tg annealing depend on the level of hydrostatic pressure. At low hydrostatic pressures, up to 2 GPa in this alloy, the relaxation rate increases with the increasing pressure. The lowest equivalent cooling rate reaches 3.3 × 106 K/s in the sample annealed at 2 GPa hydrostatic pressure, which is in the order of the cooling rate in melt spinning experiments. Higher pressures retard the relaxation rate or even rejuvenate the sample. Structural relaxation at low hydrostatic pressure during sub-Tg annealing is governed by short-range atomic rearrangements through annihilation of free volume and anti-free volume defects. In contrast, at high hydrostatic pressures, most of the atoms just experience thermal vibration rather than real atomic jumps. The formation of anti-free volume defects is the main source of structural instability at the high pressure region.
Ionic solvation and solvent-solvent interaction effects on the charge and potential distributions in electric double layers
Authors: Vangara R. , van Swol F. , Petsev D. N.
Published: December 2017

Electric double layers are complex systems that involve a wide variety of interactions between the different components of the electrolyte solutions and with the charged interface. While the role of all Coulombic types of interactions is clear, that of the non-Coulombic forces is less obvious. The focus in the present study is on the effect of bulk solvation interactions on the properties of the electric double layer. The analysis is based on classical density functional theory. This approach allows us to account for the correlations between all charged (ionic) and uncharged (solvent) species in the solution. The surface charge at the boundary of the electric double layer is derived from the surface chemistry pertinent to the system. The surface is sensitive to the concentration of potential determining ions, which in turn depends on the correlations and activities of all remaining components. The analysis shows that the solvation forces have a profound effect on the charge and potential distributions in an electric double layer. This is true not just for the solvation of the potential determining ions, but for all species. Even varying the solvent-solvent interaction has a significant impact on the charge and potential distributions in the electric double layer.
Direct imaging of sketched conductive nanostructures at the LaAlO3/SrTiO3 interface
Authors: Jiang Zhanzhi , Wu Xiaoyu , Lee Hyungwoo , Lee Jung-Woo , Li Jianan , Cheng Guanglei , Eom Chang-Beom , Levy Jeremy , Lai Keji
Published: December 2017

Nanoscale control of the quasi-two-dimensional electron gas at the LaAlO3/SrTiO3 (LAO/STO) interface by a conductive probe tip has triggered the development of a number of electronic devices. While the spatial distribution of the conductance is crucial for such devices, it is challenging to directly visualize the local electrical properties at the buried interface. Here, we demonstrate conductivity imaging of sketched nanostructures at the LAO/STO interface by microwave impedance microscopy (MIM) with a lateral resolution on the order of 100 nm. The sheet conductance extracted from the MIM data agrees with the transport measurement. The tip-induced insulator-to-metal transition is observed above a threshold voltage of +4 V. Our work paves the way for studying emergent phenomena at oxide interfaces by probing nanoscale conductance distribution.
Note: Micro-channel array crucible for isotope-resolved laser spectroscopy of high-temperature atomic beams
Authors: Lebedev Vyacheslav , Bartlett Joshua H. , Malyzhenkov Alexander , Castro Alonso
Published: December 2017

We present a novel compact design for a multichannel atomic oven which generates collimated beams of refractory atoms for fieldable laser spectroscopy. Using this resistively heated crucible, we demonstrate spectroscopy of an erbium sample at 1300 °C with improved isotopic resolution with respect to a single-channel design. In addition, our oven has a high thermal efficiency. By minimizing the surface area of the crucible, we achieve 2000 °C at 140 W of applied electrical power. As a result, the design does not require any active cooling and is compact enough to allow for its incorporation into fieldable instruments.
Perturbed path integrals in imaginary time: Efficiently modeling nuclear quantum effects in molecules and materials
Authors: Poltavsky Igor , DiStasio Robert A. , Tkatchenko Alexandre
Published: December 2017

Nuclear quantum effects (NQE), which include both zero-point motion and tunneling, exhibit quite an impressive range of influence over the equilibrium and dynamical properties of molecules and materials. In this work, we extend our recently proposed perturbed path-integral (PPI) approach for modeling NQE in molecular systems [I. Poltavsky and A. Tkatchenko, Chem. Sci. 7, 1368 (2016)], which successfully combines the advantages of thermodynamic perturbation theory with path-integral molecular dynamics (PIMD), in a number of important directions. First, we demonstrate the accuracy, performance, and general applicability of the PPI approach to both molecules and extended (condensed-phase) materials. Second, we derive a series of estimators within the PPI approach to enable calculations of structural properties such as radial distribution functions (RDFs) that exhibit rapid convergence with respect to the number of beads in the PIMD simulation. Finally, we introduce an effective nuclear temperature formalism within the framework of the PPI approach and demonstrate that such effective temperatures can be an extremely useful tool in quantitatively estimating the “quantumness” associated with different degrees of freedom in the system as well as providing a reliable quantitative assessment of the convergence of PIMD simulations. Since the PPI approach only requires the use of standard second-order imaginary-time PIMD simulations, these developments enable one to include a treatment of NQE in equilibrium thermodynamic properties (such as energies, heat capacities, and RDFs) with the accuracy of higher-order methods but at a fraction of the computational cost, thereby enabling first-principles modeling that simultaneously accounts for the quantum mechanical nature of both electrons and nuclei in large-scale molecules and materials.
On the non-stationary generalized Langevin equation
Authors: Meyer Hugues , Voigtmann Thomas , Schilling Tanja
Published: December 2017

In molecular dynamics simulations and single molecule experiments, observables are usually measured along dynamic trajectories and then averaged over an ensemble (“bundle”) of trajectories. Under stationary conditions, the time-evolution of such averages is described by the generalized Langevin equation. By contrast, if the dynamics is not stationary, it is not a priori clear which form the equation of motion for an averaged observable has. We employ the formalism of time-dependent projection operator techniques to derive the equation of motion for a non-equilibrium trajectory-averaged observable as well as for its non-stationary auto-correlation function. The equation is similar in structure to the generalized Langevin equation but exhibits a time-dependent memory kernel as well as a fluctuating force that implicitly depends on the initial conditions of the process. We also derive a relation between this memory kernel and the autocorrelation function of the fluctuating force that has a structure similar to a fluctuation-dissipation relation. In addition, we show how the choice of the projection operator allows us to relate the Taylor expansion of the memory kernel to data that are accessible in MD simulations and experiments, thus allowing us to construct the equation of motion. As a numerical example, the procedure is applied to Brownian motion initialized in non-equilibrium conditions and is shown to be consistent with direct measurements from simulations.
Using machine learning to replicate chaotic attractors and calculate Lyapunov exponents from data
Authors: Pathak Jaideep , Lu Zhixin , Hunt Brian R. , Girvan Michelle , Ott Edward
Published: December 2017

We use recent advances in the machine learning area known as “reservoir computing” to formulate a method for model-free estimation from data of the Lyapunov exponents of a chaotic process. The technique uses a limited time series of measurements as input to a high-dimensional dynamical system called a “reservoir.” After the reservoir's response to the data is recorded, linear regression is used to learn a large set of parameters, called the “output weights.” The learned output weights are then used to form a modified autonomous reservoir designed to be capable of producing an arbitrarily long time series whose ergodic properties approximate those of the input signal. When successful, we say that the autonomous reservoir reproduces the attractor's “climate.” Since the reservoir equations and output weights are known, we can compute the derivatives needed to determine the Lyapunov exponents of the autonomous reservoir, which we then use as estimates of the Lyapunov exponents for the original input generating system. We illustrate the effectiveness of our technique with two examples, the Lorenz system and the Kuramoto-Sivashinsky (KS) equation. In the case of the KS equation, we note that the high dimensional nature of the system and the large number of Lyapunov exponents yield a challenging test of our method, which we find the method successfully passes.
Hybrid setup for micro- and nano-computed tomography in the hard X-ray range
Authors: Fella Christian , Balles Andreas , Hanke Randolf , Last Arndt , Zabler Simon
Published: December 2017

With increasing miniaturization in industry and medical technology, non-destructive testing techniques are an area of ever-increasing importance. In this framework, X-ray microscopy offers an efficient tool for the analysis, understanding, and quality assurance of microscopic samples, in particular as it allows reconstructing three-dimensional data sets of the whole sample’s volume via computed tomography (CT). The following article describes a compact X-ray microscope in the hard X-ray regime around 9 keV, based on a highly brilliant liquid-metal-jet source. In comparison to commercially available instruments, it is a hybrid that works in two different modes. The first one is a micro-CT mode without optics, which uses a high-resolution detector to allow scans of samples in the millimeter range with a resolution of 1 μm. The second mode is a microscope, which contains an X-ray optical element to magnify the sample and allows resolving 150 nm features. Changing between the modes is possible without moving the sample. Thus, the instrument represents an important step towards establishing high-resolution laboratory-based multi-mode X-ray microscopy as a standard investigation method.
Multicomponent solitons present an optical realization of parity-time-symmetric dynamical systems
Authors: Woo Marcus
Published: December 2017

Researchers find stable solitons of coupled nonlinear Schrödinger equations with parity-time-symmetric potentials with a reverse engineering method.
Role of activin C in normal ovaries and granulosa cell tumours of mice and humans
Authors: Reader Karen L. , Marino Francesco E. , Nicholson Helen D. , Risbridger Gail P. , Gold Elspeth J.
Published: December 2017

Activins and inhibins play important roles in the development, growth and function of the ovary. Mice lacking inhibin develop granulosa cell tumours in their ovaries that secrete activin A, and these tumours are modulated by increased activin C expression. The aim of the present study was to identify where activin C is expressed in mouse and human ovaries and whether overexpression of activin C modulates normal follicular development in mice. Immunohistochemical staining for the activin βC subunit was performed on sections from mouse and human ovaries and human adult granulosa cell tumours. Stereology techniques were used to quantify oocyte and follicular diameters, and the percentage of different follicular types in ovaries from wild-type mice and those underexpressing inhibin α and/or overexpressing activin C. Staining for activin βC was observed in the oocytes, granulosa cells, thecal cells and surface epithelium of mouse and human ovaries, and in the granulosa-like cells of adult granulosa cell tumours. Overexpression of activin C in mice did not alter follicular development compared with wild-type mice, but it did modulate the development of abnormal early stage follicles in inhibin α-null mice. These results provide further evidence of a role for activin C in the ovary.
Student movements in Kosova (1981): academic or nationalist?
Authors: Hetemi Atdhe
Published: December 2017

The 1980s caught Albanians in Kosova in interesting social, political, and psychological circumstances. Two diametrically opposed dogmatic dilemmas took shape: “illegal groups” – considerably supported by students – demanded the proclamation of the Republic of Kosova and/or Kosova's unification with Albania. On the other side of the spectrum, “modernists” – gathering, among others, the political and academic elites – pushed for the improvement of rights of Kosovars guaranteed under the “brotherhood and unity” concept advocated within the Socialist Federal Republic of Yugoslavia (SFRY). This paper outlines the nature of demonstrations that took place in March and April 1981 and the corresponding responses of political and academic elites. Stretching beyond symbolic academic reasons – demands for better food and dormitory conditions – the study points to the intense commitment of the students to their demands, often articulated in nationalistic terms. Was it inevitable that the structure of the SFRY would lead to those living in Kosova as a non-Slavic majority in a federation of “Southern Slavs” to articulate demands for national self-rule? It is necessary to highlight these political and social complexities through analytical approaches in order to track the students' goals and to reexamine assumptions behind the “modernist” agenda. In that vein, the paper analyzes the conceptual connections and differences between student reactions and modernists' positions during the historical period under discussion here.
Isogloiosiphone B, a novel acetal, and hydrophobic compounds as β-glucuronidase inhibitors derived from the red alga Neodilsea yendoana
Authors: Zhang Duo , Kurihara Hideyuki
Published: December 2017

A novel acetal named isogloiosiphone B was isolated from the red alga Neodilsea yendoana, along with three known hydrophobic compounds as β-glucuronidase inhibitors. The acetal was determined as a naturally occurring compound from the extraction experiments with several kinds of solvent. The acetal showed the highest inhibition against β-glucuronidase among the compounds examined.
First synthesis of (S)-(+)-hymenoic acid, a DNA polymerase λ inhibitor isolated from Hymenochaetaceae sp
Authors: Takahashi Kensuke , Matsui Miki , Kuse Masaki , Takikawa Hirosato
Published: December 2017

Hymenoic acid, isolated from cultures of the fungus, Hymenochaetaceae sp., is a specific inhibitor of DNA polymerase λ. The first synthesis of (S)-(+)-hymenoic acid was achieved by starting from trans-1,4-cyclohexanedimethanol and methyl (R)-(−)-3-hydroxyisobutyrate, and Julia–Kocienski olefination was employed as the key step.
Enhancement of natural killer activity and IFN-γ production in an IL-12-dependent manner by aBrassica rapaL.
Authors: Yamamoto Kana , Furuya Kanon , Yamada Kazuki , Takahashi Fuka , Hamajima Chisato , Tanaka Sachi
Published: December 2017

Certain food components possess immunomodulatory effects. The aim of this study was to elucidate the mechanism of the immunostimulatory activity of Brassica rapa L. We demonstrated an enhancement of natural killer (NK) activity and interferon (IFN)-γ production in mice that were orally administered an insoluble fraction of B. rapa L. The insoluble fraction of B. rapa L. significantly induced IFN-γ production in mouse spleen cells in an interleukin (IL)-12-dependent manner, and NK1.1+ cells were the main cells responsible for producing IFN-γ. Additionally, the results suggested that the active compounds in the insoluble fraction were recognized by Toll-like receptor (TLR) 2, TLR4, and C-type lectin receptors on dendritic cells, and they activated signaling cascades such as MAPK, NF-κB, and Syk. These findings suggest that B. rapa L. is a potentially promising immuno-improving material, and it might be useful for preventing immunological disorders such as infections and cancers by activating innate immunity.
Legal Rhetoric and the Ambiguous Shape of the King’s Two Bodies in Calvin’s Case (1608)
Authors: Franz Margaret
Published: December 2017

This essay examines how Francis Bacon’s speech in Calvin’s Case (1608) and Edward Coke’s report on the case engage with the doctrine of the king’s two bodies. While both texts portray the subject as perpetually obligated to the king’s personal body, the ambiguity of the doctrine combined with the topical resources of early-modern legal rhetoric allowed for disparate constructions of the king’s two bodies that could at once support and displace the absolute sovereignty of the king’s personal body. In the end, I argue that both texts offer distinct contributions to the early-modern era’s budding anti-royalist discourse.
Aristotle’s Rhetorical Energeia: An Extended Note
Authors: Westin Monica
Published: December 2017

In Book III of the Rhetoric, Aristotle focuses at length on the effect of lexical energeia. Scholarship on energeia in this passage almost always associates it with with analysis of enargeia in later texts. However, it is not clear that these two are used as equivalents in Aristotle. Here I survey Aristotle’s conceptions of energeia across the corpus in order to understand Aristotle’s use of energeia in the Rhetoric more precisely. I argue that Aristotle’s model of energeia has a consistent fundamental meaning, even as it crosses many topoi, and that Aristotle’s rhetorical energeia cannot be conflated with enargeia.
Affine zigzag algebras and imaginary strata for KLR algebras
Authors: Kleshchev Alexander , Muth Robert
Published: December 2017

KLR algebras of affine

ADE

\texttt {ADE}

types are known to be properly stratified if the characteristic of the ground field is greater than some explicit bound. Understanding the strata of this stratification reduces to semicuspidal cases, which split into real and imaginary subcases. Real semicuspidal strata are well understood. We show that the smallest imaginary stratum is Morita equivalent to Huerfano-Khovanov’s zigzag algebra tensored with a polynomial algebra in one variable. We introduce affine zigzag algebras and prove that these are Morita equivalent to arbitrary imaginary strata if the characteristic of the ground field is greater than the bound mentioned above.
3. Industry
Authors: Nowell-Smith Geoffrey
Published: December 2017

The cinema is an industry, but it did not become an industry overnight, nor did it do so as an automatic consequence of its technological base. What set cinema on the road to becoming an industry in the early years were the needs of commerce, as the new medium spread rapidly across the globe. ‘Industry’ describes the development of the Hollywood studio system and how that practice was imitated in Europe and Asia. It goes on to outline how the structure of world cinema changed through trade liberalization and mass migration. Despite numerous changes, the world’s film industries continue to follow the template set down nearly a century ago, in the 1920s.
6. Conclusion: seven epochs of cinema
Authors: Nowell-Smith Geoffrey
Published: December 2017

The cinema has not developed in a straight line, nor has it simply progressed to greater and greater achievements. Instead, it developed in different ways in different places at different times, under conflicting pressures and serving changing needs. The Conclusion brings the separate threads discussed throughout this VSI together—technology, industry, artistic forms, and interaction with the outside world—and divides the history of the cinema to date into seven epochs, each of approximately fifteen years’ duration: 1900–14, from cinematograph to cinema; 1915–29, the heyday of the silent; 1930–44, the talkies; 1945–59, after World War II; 1960–74, the new waves; 1975–89; and 1990 to the present.
1. What are miracles?
Authors: Nagasawa Yujin
Published: December 2017

The concept of a miracle is elusive. We all know roughly what a miracle is, yet we struggle to state a precise definition. The proper definition of a miracle has been disputed among philosophers for centuries. ‘What are miracles?’ considers a wide range of concrete examples that represent or misrepresent miracles, and examines which conditions are necessary or sufficient for the concept to apply. It looks at ‘miracles’ in sport, technology, and nature; coincidences and religious signs as miracles; and the concept of impossibility. It concludes that a miracle is a violation of the laws of nature that is caused by an intentional agent and has religious significance.
4. Is it rational to believe in miracles?
Authors: Nagasawa Yujin
Published: December 2017

‘Is it rational to believe in miracles?’ considers the most crucial question concerning miracles by scrutinizing existing arguments against belief in miracles. The best-known critic of belief in miracles is David Hume, an 18th-century Scottish philosopher. Hume makes two main claims against miracles: (i) in fact, there has never been enough evidence for miracles; (ii) on principle, it is always unreasonable to believe in miracles. Even if Hume’s arguments fail, it may be that gathering enough evidence for miracles is practically impossible. Therefore, even if we directly encountered a miracle, we would struggle to convince others and even ourselves that a miracle had really taken place.
3. Adaptive immunity: a voyage of (non-)self-discovery
Authors: Klenerman Paul
Published: December 2017

How does the immune system respond to such diverse threats, including viruses never encountered previously by us as a species? The inherent diversity in the immune system can be explained by examining how the adaptive immune system is built, in particular the receptors on B and T lymphocytes. ‘The adaptive immune system: a voyage of (non-)self-discovery’ describes B and T cells, receptors, and the creation of antibodies. Antibody genes are not created as a single unit but are made up from smaller parts, generating many more possible combinations. The antibodies that are created from the genetic template are further honed, becoming highly specific to their target.
4. Making memories
Authors: Klenerman Paul
Published: December 2017

The ability of the immune system to sense pathogens and how they can be targeted specifically needs to be tightly coordinated in space and over time. ‘Making memories’ considers how the immune response develops following exposure to a virus. To make effective memory, the immune response needs to be induced correctly or ‘primed’ during the initial stages of an infection. The first step is for the immune system to develop a response relating to the activation of the innate immune system. Without this, the adaptive response is often subsequently overwhelmed. The mechanics of memory formation and how this is then harnessed in current vaccines are described.
6. Too much immunity: auto-immunity and allergic diseases
Authors: Klenerman Paul
Published: December 2017

Given the capacity to cause tissue damage and inflammation, every immune response must be appropriately and specifically tuned. Failure to tune appropriately leads to a range of immunologically driven diseases that, given the general improvements in health status and many major infections in Western populations, have taken on increasing significance. ‘Too much immunity: auto-immunity and allergic diseases’ considers how the immune system acts to turn off unwanted responses, and what goes wrong when this fails. This includes looking at classical auto-immune diseases, other diseases where there is excessive inflammation, and allergic diseases where there is an exaggerated response to harmless antigens, dominated by a particular style of immunity.
3. Colonial India: religious and caste divides
Authors: Jeffrey Craig
Published: December 2017

India is often identified as a Hindu country, but there are many other religions in India including Buddhism, Jainism, Islam, Sikhism, Zoroastrianism, Judaism, and Christianity. ‘Colonial India: religious and caste divides’ explains India’s religious diversity and the inequalities that are associated with the assumed ‘Hindu-ness’ of India. It also describes the Partition of India into three new nations in 1947 and the accompanying violence. A sharply hierarchical caste system is not necessarily a natural feature of Indian society. Caste is rather a social institution that has changed historically in response to economic and political forces. The imperial power introduced or exacerbated social contradictions that continue to mark the lives of low castes in modern India.
5. Rethinking India
Authors: Jeffrey Craig
Published: December 2017

The period between 1989 and 1992—roughly the period during which the National Front Government presided over India—was pivotal in the development of the country. Two key shifts were especially important. First, caste reservations became a major political issue and low castes became much more powerful within politics. Second was the rise of Hindu nationalism and the Bharatiya Janata Party. ‘Rethinking India’ also describes economic reforms in the early 1990s and the rising prominence of India on the global stage. The economic reforms have reduced poverty, but not as effectively as might have been expected; they have also exacerbated inequalities between the urban and the rural.
7. Youth
Authors: Jeffrey Craig
Published: December 2017

One in ten people in the world are an Indian youth aged under 30. This enormous population is poised to make a major contribution to the future of their country and the world. In India, as elsewhere, the hopes of the nation are projected onto youth. But are the conditions in India conducive to young people fulfilling societal hopes? If not, what can young people do to improve the situation in which they live? A large young adult population can be a ‘demographic dividend’ for a country, but only if the institutional and infrastructural environment is right. ‘Youth’ considers the state of education and healthcare in India today along with employment prospects for the young and youth politics.
Introduction
Authors: Beaney Michael
Published: December 2017

One claim often made about analytic philosophy is that it places great emphasis on clarity of thinking, precision of expression, and rigour of argumentation. But other intellectual virtues that might be considered are creativity, fruitfulness, and systematicity. The Introduction aims to give some sense of the conceptual creativity of analytic philosophy and the bigger picture in which its fruitfulness and systematic ambitions can be appreciated. Analytic philosophy is called ‘analytic’ because of the emphasis placed on analysis. But this just raises the question of what is meant by ‘analysis’, and what forms of analysis are employed in analytic philosophy. This is best answered by considering a range of philosophical questions.
How can we speak of what does not exist?
Authors: Beaney Michael
Published: December 2017

Statements that purportedly refer to something that does not exist, whether fictional or not, have been especially problematic in the history of philosophy. ‘How can we speak of what does not exist?’ suggests that in order to understand existential statements, we need to recall Frege’s claim that number statements are assertions about concepts. Existential statements are really just a type of number statement. When we make an existential claim, we are not attributing a first-level concept to an object, but a second-level concept to a first-level concept. The work of Bertrand Russell (1872–1970) is also discussed along with the Russell Paradox and his Theory of Descriptions.
Are there limits to what we can say or think?
Authors: Beaney Michael
Published: December 2017

‘Are there limits to what we can say and think?’ considers the possible limits of our language and whether we can have thoughts that outstrip our ability to say what they are. It introduces Ludwig Wittgenstein (1889–1951), arguably the greatest philosopher of the 20th century, and his publication, Tractatus Logico-Philosophicus (1921), which describes his philosophical ideas. The paradox of inference is discussed along with how Wittgenstein distinguishes between senselessness and nonsense. It concludes that there are indeed limits to what we can say or think, and while there may be difficulties in saying what they are, they can certainly be shown by carefully elucidating the complex workings of language.
So what is analytic philosophy?
Authors: Beaney Michael
Published: December 2017

There are various similarities and differences between the respective approaches to analytic philosophy of Frege, Russell, Moore, Wittgenstein, and Stebbing. But is there anything in common that could be taken to characterize analytic philosophy as a whole? ‘So what is analytic philosophy?’ explains that analytic philosophy is ‘analytic’ in an extra special sense because it made use of modern logic together with all the new techniques that emerged in its wake and the greater understanding of the relationship between logic and language that this generated. It looks at later analytic philosophy—ordinary language philosophy, ideal language philosophy, and scientific philosophy—before considering what is wrong and good about analytic philosophy.
1. The data explosion
Authors: Holmes Dawn E.
Published: December 2017

‘The data explosion’ introduces the reader to the diversity of data in general before explaining how the digital age has led to changes in the way we define data. Big data is introduced informally through the idea of the data explosion, involving computer science, statistics, and the interface between them. It discusses search engine data, healthcare data, astronomical data, and real-time data such as the information provided by Global Positioning Systems. But what use is all this data? The ultimate aim of working with big data is to extract useful information. Combining traditional statistics and computer science allows large datasets to be analysed to search for key patterns.
2. Why is big data special?
Authors: Holmes Dawn E.
Published: December 2017

The rapid growth in computing power and storage has led to progressively more data being collected. Big datasets are certainly large and complex, but in order to fully define ‘big data’ we need first to understand ‘small data’ and its role in statistical analysis. ‘Why is big data special?’ considers the four main characteristics of big data: volume, variety, velocity, and veracity, which present a considerable challenge in data management. The advantages we expect to gain from meeting this challenge and the questions we hope to answer with big data can be understood through data mining. The use of big data mining in credit card fraud detection is discussed.
3. Storing big data
Authors: Holmes Dawn E.
Published: December 2017

The amount of data generated is approximately doubling every two years. How do we store and manage these colossal amounts of data? ‘Storing big data’ considers database storage and the idea of distributing tasks across clusters of computers. Relational database management systems are used to create, maintain, access, and manipulate structured data, whereas distributed file systems provide effective and reliable storage for unstructured data across many servers. NoSQL databases and their architecture are discussed along with the CAP Theorem and Cloud storage. The difference between lossless compression for text files and lossy data compression for sound and image files is also explained.
5. Big data and medicine
Authors: Holmes Dawn E.
Published: December 2017

Big data analysis is changing the world of healthcare. Its potential has yet to be fully realized, but includes medical diagnosis, epidemic prediction, gauging public response to government health warnings, and the reduction in costs. ‘Big data and medicine’ considers healthcare informatics, which uses big data to provide improved patient care and reduce costs. Mining social media data for public health related research is now a recognized practice within the academic community. Google Flu Trends is discussed along with the Watson medical system, which retrieves and analyses structured and unstructured data. Big data use in healthcare evidently has great potential, but what about the privacy of the individual’s medical data?
The Role of a Neuropsychologist on a Movement Disorders Deep Brain Stimulation Team
Authors: Kubu Cynthia S
Published: December 2017

The term movement disorders is misleading in the implication that the symptoms are limited to motor problems. Most movement disorders include a variety of neurobehavioral and neurocognitive symptoms that require neuropsychological expertise. The goal of this paper is to provide a rationale and practical roadmap for neuropsychologists’ involvement in a Movement Disorders team with a specific focus on pre-operative deep brain stimulation (DBS) evaluations. Pragmatic recommendations regarding requisite skills, clinical practice, recommendations, communication, and benefits are outlined.