bluuebunny/crossref_metadata_2025 huggingface dataset:
Wars, inflation and stock market returns in France, 1870–1945
Authors: Le Bris David
Published: September 2012

This article undertakes a comparative study of the effects of three wars upon the French stock market. Periods of war are highly turbulent financial times and trigger multiple factors to act upon stock prices. The article presents evidence suggesting that stock price behaviour is influenced by the specific way each war is financed. Financed solely by regular long-term debt, the Franco-Prussian War exhibited stock prices that only reflected real activity. On the other hand, both world wars were partially financed by monetary creation but differed with regard to the extent of financial repression. In the case of World War II, monetary creation within a closed repressed economy led to a paradoxical, short-lived increase in stock prices. The article also examines how war affected the characteristics of the market. The Franco-Prussian War caused a durable high interest rate; World War I smoothed out most of the public services firms and increased volatility; whilst World War II affected the components of the stock market. Overall, mainly due to market values being destroyed during the world wars, the importance of the stock market in the economy decreased.
BEYOND ATHEISM
Authors: Glendinning Simon
Published: September 2012

This essay defends the idea of drawing a distinction between two modes of not being religious today: between what I will call atheist disbelief, on the one hand, and a-theist non-belief on the other. The former is the mode which is most often in the news. It is the position that pitches itself against religion. The latter is perhaps easily confused with agnosticism as that is popularly understood. Agnosticism in this sense is a position in which you declare yourself undecided or unsure: one is not sufficiently convinced that God does not exist to affirm a full-blooded atheism, but equally, spiritual conceptions, for example as determined by the Christian Churches, do not persuade you either. The situation as regards what I am calling a-theist non-belief is different again: it is not so much a ‘position’ at all as a non-religious ‘habitus’: the understanding of the world and the significance of your life that characterises the a-theist life is one in which religion and religious beliefs, for the most part, just do not figure or play a part. The a-theist does not have positional stance towards religious beliefs – namely a stance of disbelief – but rather, for the most part, simply has no thoughts about God. While not agnostic, the a-theist resembles the agnostic is this respect: conceptually speaking the a-theist is no closer to atheism than he or she is to religious faith. In my view, while the a-theist habitus is incredibly widespread today it is nevertheless typically overlooked in discussions of contemporary faith and atheism. Perhaps this is because it seems so comparatively unreflective and uncommitted. Nevertheless, I will champion it in this essay.
MATHEMATICS: DISCOVERY OR INVENTION?
Authors: Fine Kit
Published: September 2012

Mathematics has been the most successful and is the most mature of the sciences. Its first great master work – Euclid's ‘Elements’ – which helped to establish the field and demonstrate the power of its methods, was written about 2400 years ago; and it served as a standard text in the mathematics curriculum well into the twentieth century. By contrast, the first comparable master work of physics – Newton's Principia – was written 300 odd years ago. And the juvenile science of biology only got its first master work – Darwin's ‘On the Origin of Species’ – a mere 150 years ago. The development of the subject has also been extraordinarily fertile, particularly in the last three centuries, and it is perhaps only in the last century that the other sciences have begun to approach mathematics in the steady accumulation of knowledge that it has been able to offer. There has, moreover, been almost universal agreement on its methods and how they are to be applied. What we require is proof; and, in practice, there is very little disagreement over whether or not we have it. The other sciences, by contrast, tend to get mired in controversy over the significance of this or that experimental finding or over whether one theory is to be preferred to another.
Pex5p stabilizes Pex14p: a study using a newly isolated pex5 CHO cell mutant, ZPEG101
Authors: Natsuyama Ryuichi , Okumoto Kanji , Fujiki Yukio
Published: September 2012

Pex5p [PTS (peroxisome-targeting signal) type 1 receptor] plays an essential role in peroxisomal matrix protein import. In the present study, we isolated a novel PEX5-deficient CHO (Chinese-hamster ovary) cell mutant, termed ZPEG101, showing typical peroxisomal import defects of both PTS1 and PTS2 proteins. ZPEG101 is distinct from other known pex5 CHO mutants in its Pex5p expression. An undetectable level of Pex5p in ZPEG101 results in unstable Pex14p, which is due to inefficient translocation to the peroxisomal membrane. All of the mutant phenotypes of ZPEG101 are restored by expression of wild-type Pex5pL, a longer form of Pex5p, suggesting a role for Pex5p in sustaining the levels of Pex14p in addition to peroxisomal matrix protein import. Complementation analysis using various Pex5p mutants revealed that in the seven pentapeptide WXXXF/Y motifs in Pex5pL, known as the multiple binding sites for Pex14p, the fifth motif is an auxiliary binding site for Pex14p and is required for Pex14p stability. Furthermore, we found that Pex5p–Pex13p interaction is essential for the import of PTS1 proteins as well as catalase, but not for that of PTS2 proteins. Therefore ZPEG101 with no Pex5p would be a useful tool for investigating Pex5p function and delineating the mechanisms underlying peroxisomal matrix protein import.
Control of amyloid assembly by autoregulation
Authors: Landreh Michael , Johansson Jan , Rising Anna , Presto Jenny , Jörnvall Hans
Published: September 2012

The assembly of proteins into amyloid fibrils can be an element of both protein aggregation diseases and a functional unit in healthy biological pathways. In both cases, it must be kept under tight control to prevent undesired aggregation. In normophysiology, proteins can self-chaperone amyloidogenic segments by restricting their conformational flexibility in an overall stabilizing protein fold. However, some aggregation-prone segments cannot be controlled in this manner and require additional regulatory elements to limit fibrillation. The present review summarizes different molecular mechanisms that proteins use to control their own assembly into fibrils, such as the inclusion of a chaperoning domain or a blocking segment in the proform, the controlled release of an amyloidogenic region from the folded protein, or the adjustment of fibrillation propensity according to pH. Autoregulatory elements can control disease-related as well as functional fibrillar protein assemblies and distinguish a group of self-regulating amyloids across a wide range of biological functions and organisms.
Expression of a glycosylphosphatidylinositol-anchored ligand, growth hormone, blocks receptor signalling
Authors: Guesdon François , Kaabi Yahia , Riley Aiden H. , Wilkinson Ian R. , Gray Colin , James David C. , Artymiuk Peter J. , Sayers Jon R. , Ross Richard J.
Published: September 2012

We have investigated the interaction between GH (growth hormone) and GHR (GH receptor). We previously demonstrated that a truncated GHR that possesses a transmembrane domain but no cytoplasmic domain blocks receptor signalling. Based on this observation we investigated the impact of tethering the receptor's extracellular domain to the cell surface using a native lipid GPI (glycosylphosphatidylinositol) anchor. We also investigated the effect of tethering GH, the ligand itself, to the cell surface and demonstrated that tethering either the ecGHR (extracellular domain of GHR) or the ligand itself to the cell membrane via a GPI anchor greatly attenuates signalling. To elucidate the mechanism for this antagonist activity, we used confocal microscopy to examine the fluorescently modified ligand and receptor. GH–GPI was expressed on the cell surface and formed inactive receptor complexes that failed to internalize and blocked receptor activation. In conclusion, contrary to expectation, tethering an agonist to the cell surface can generate an inactive hormone receptor complex that fails to internalize.
Importance and estimation of mismatch uncertainty for RF parameters in calibration laboratories
Authors: Patel K. , Negi P.S.
Published: September 2012

A number of calibration techniques are used in Radio Frequency (RF) calibration for power, attenuation and impedance parameters. Mismatch uncertainty plays a major role in these measurements and in estimation of combined uncertainty according to ISO/IEC 17025:2005 and GUM document. Formulas to evaluate the mismatch uncertainty in terms of reflection coefficient, voltage standing wave ratio and scattering parameters have been evaluated earlier and are being used in RF calibration. The present paper summarizes the mismatch formulas previously studied and the modified ones suitable to the measurement system and techniques available today. For power and attenuation calibration in the particular frequency range, an establishment of traceability for one-port measurement in the same frequency range is required. The methods to reduce and control this uncertainty component and their limitations are also discussed forbest measurements practices in the calibration laboratories.
Analytic calculation of Witten index in D = 2 supersymmetric Yang-Mills quantum mechanics
Authors: Korcyl Piotr
Published: September 2012

We evaluate analytically the Witten index of D = 2 supersymmetric Yang-Mills quantum mechanics. We rederive a known result for the SU(2) gauge group and generalize it to any SU(N) gauge group.
1.5D quasilinear model and its application on beams interacting with Alfvén eigenmodes in DIII-D
Authors: Ghantous K. , Gorelenkov N. N. , Berk H. L. , Heidbrink W. W. , Van Zeeland M. A.
Published: September 2012

We propose a model, denoted here by 1.5D, to study energetic particle (EP) interaction with toroidal Alfvenic eigenmodes (TAE) in the case where the local EP drive for TAE exceeds the stability limit. Based on quasilinear theory, the proposed 1.5D model assumes that the particles diffuse in phase space, flattening the pressure profile until its gradient reaches a critical value where the modes stabilize. Using local theories and NOVA-K simulations of TAE damping and growth rates, the 1.5D model calculates the critical gradient and reconstructs the relaxed EP pressure profile. Local theory is improved from previous study by including more sophisticated damping and drive mechanisms such as the numerical computation of the effect of the EP finite orbit width on the growth rate. The 1.5D model is applied on the well-diagnosed DIII-D discharges #142111 [M. A. Van Zeeland et al., Phys. Plasmas 18, 135001 (2011)] and #127112 [W. W. Heidbrink et al., Nucl. Fusion. 48, 084001 (2008)]. We achieved a very satisfactory agreement with the experimental results on the EP pressure profiles redistribution and measured losses. This agreement of the 1.5D model with experimental results allows the use of this code as a guide for ITER plasma operation where it is desired to have no more than 5% loss of fusion alpha particles as limited by the design.
Puffin: A three dimensional, unaveraged free electron laser simulation code
Authors: Campbell L. T. , McNeil B. W. J.
Published: September 2012

An unaveraged 3D model of the free electron laser (FEL) is presented which is capable of modelling electron interactions with broad bandwidth radiation that includes electron beam shot-noise and coherent spontaneous emission effects. Non-localised electron transport throughout the beam is modelled self-consistently allowing better modelling of systems where a larger electron energy range is required. The FEL interaction can be modelled with undulator fields of variable polarisation. A modular undulator system allows insertion of other magnetic structures, such as chicanes. A set of working equations that describe the model are derived, the parallel numerical method that solves them described, and some example FEL interactions presented.
Influence of carbon content and nitrogen vacancies on the bonding structure and mechanical performance of graphite-like BCxN thin films
Authors: Caretti Ignacio , Jiménez Ignacio
Published: September 2012

X-ray absorption near edge structure (XANES) was used to investigate two sets of graphite-like BCxN thin films with similar B:C:N ratios but different amounts of nitrogen vacancies, which become oxygen-filled in the surface-most region. The two sets of samples were grown on Si (100) at room temperature by ion beam assisted deposition using two different ion/atom ratios. Nitrogen vacancy defects were detected in the B1s XANES spectra due to an oxygen decoration mechanism taking place at the film surface, which is correctly described by a core-level shift model. Analysis of the O1s XANES spectra showed two different types of oxygen incorporation in the samples under study. The tribomechanical properties of the BCxN samples were tested by the pin-on-disk technique, revealing the substantial role played by both the carbon intake in the hexagonal BCN planes and the concentration of nitrogen vacancies generated during the growth.
One-dimensional plate impact experiments on the cyclotetramethylene tetranitramine (HMX) based explosive EDC32
Authors: Burns Malcolm J. , Gustavsen Richard L. , Bartram Brian D.
Published: September 2012

Eight one-dimensional plate impact experiments have been performed to study both the Shock to Detonation Transition and Hugoniot state in the cyclotetramethylene tetranitramine (HMX) based explosive EDC32. The experiments covered shock pressures ranging from 0.59 to 7.5 GPa with sustained shocks, double shocks, and short pulse shocks. Experiments were instrumented with embedded magnetic particle velocity gauges. Results include; (1) wave profiles of particle velocity vs. time vs. depth in the explosive, (2) time-distance coordinates for onset of detonation vs. initial shock pressure (aka the Pop-plot), (3) a reactants Hugoniot, and (4) measurement of the Hugoniot Elastic Limit of 0.22.GPa.
Microparticles deep in the plasma sheath: Coulomb “explosion”
Authors: Antonova T. , Du C.-R. , Ivlev A. V. , Annaratone B. M. , Hou L.-J. , Kompaneets R. , Thomas H. M. , Morfill G. E.
Published: September 2012

A cloud of microparticles was trapped deep in the sheath of a radio-frequency (rf) discharge, very close to the lower (grounded) electrode of the plasma chamber. This was achieved by employing a specifically designed rf-driven segment integrated in the lower electrode, which provided an additional confinement compressing the cloud to a very high density. After switching the rf-driven segment off, the cloud “exploded” due to mutual interparticle repulsion. By combining a simple theoretical model with different numerical simulation methods, some basic properties of complex plasmas in this highly non-equilibrium regime were determined.
Development of miniaturized, portable magnetic resonance relaxometry system for point-of-care medical diagnosis
Authors: Peng Weng Kung , Chen Lan , Han Jongyoon
Published: September 2012

A novel, compact-sized (19 cm × 16 cm) and portable (500 g) magnetic resonance relaxometry system is designed and developed. We overcame several key engineering barriers so that magnetic resonance technology can be potentially used for disease diagnosis-monitoring in point-of-care settings, directly on biological cells and tissues. The whole system consists of a coin-sized permanent magnet (0.76 T), miniaturized radio-frequency microcoil probe, compact lumped-circuit duplexer, and single board 1-W power amplifier, in which a field programmable gate array -based spectrometer is used for pulse excitation, signal acquisition, and data processing. We show that by measuring the proton transverse relaxation rates from a large pool of natural abundance proton-nuclei presence in less than 1 μL of red blood cells, one can indirectly deduce the relative magnetic susceptibility of the bulk cells within a few minutes of signal acquisition time. Such rapid and sensitive blood screening system can be used to monitor the fluctuation of the bulk magnetic susceptibility of the biological cells (e.g., human blood cells), where unusual state of the bulk magnetic susceptibility is related to a number of diseases.
Electrically induced enormous magnetic anisotropy in Terfenol-D/lead zinc niobate-lead titanate multiferroic heterostructures
Authors: Liu Ming , Li Shandong , Zhou Ziyao , Beguhn Shawn , Lou Jing , Xu Feng , Jian Lu Tian , Sun Nian X.
Published: September 2012

Electric field (E-field) tunable multiferroic devices such as tunable RF devices and memory storage mediums require strong magnetoelectric interactions. In this paper, we demonstrated a Terfenol-D/lead zinc niobate-lead titanate composite bilayer structure with an E-field-induced magnetic anisotropy field of 3500 Oe and a magnetoelectric coefficient of 580 Oe cm/kV. This is the largest E-field induced anisotropy reported to date, resulting in a strong dependence of magnetization process and tunable ferromagnetic resonance in both amorphous and crystalline Terfenol-D films. In addition, the magnetostriction constants of crystalline and amorphous Terfenol-D were estimated to be 420 ppm and 320 ppm, respectively, which are close to report values. Electrically manipulating magnetic performance holds great potential for future ultra-low power, lightweight, tunable magnetic devices, and memory storage.
Adaptive node-to-node pinning synchronization control of complex networks
Authors: Turci Luiz Felipe R. , Macau Elbert. E. N.
Published: September 2012

In this work, we propose an adaptive node-to-node pinning control strategy. In this approach, both the coupling strength among nodes and the pinning control gains are adaptively changed according to well chosen adaptation laws that take into account the specificities of the oscillators and the network topology. Proof of stability and performance comparison is also shown in this paper.
Label-free and real-time detections of the interactions of swine IgG with goat anti-swine IgG by oblique-incidence reflectivity difference technique
Authors: Wang J. Y. , Dai J. , He L. P. , Sun Y. , Lu H. B. , Jin K. J. , Yang G. Z.
Published: September 2012

With the oblique-incidence reflectivity difference (OIRD) technique, we successfully label-free detected the interaction of swine IgG with different concentrations of 0.125, 0.25, 0.5, 1 mg/ml, and 5 μg/ml goat anti-swine IgG, and real-time detected the reaction dynamic processes of 0.5 mg/ml swine IgG and goat anti-swine IgG with different concentration of 5, 10, and 20 μg/ml, respectively. The interaction times are about 2043, 1828, and 1347 s for the reactions of 0.5 mg/ml swine IgG and goat anti-swine IgG of 5, 10, and 20 μg/ml, respectively. By fitting the reaction dynamic curves, we obtained that the association constant of swine IgG and goat anti-swine IgG is 1620.77 M−1·S−1 at temperature about 22 °C. The experimental results demonstrate that the OIRD is a promising and competing method for label-free and real time detecting the biomolecular interactions and achieving the quantitative information of reaction kinetics.
A molecular analysis of carbon nanotori formation
Authors: Chang I-Ling , Chou Jiu-Wen
Published: September 2012

This study uses molecular dynamics simulation to examine the geometric criteria and stability of forming a perfect carbon nanotorus without pentagon-heptagon defects or surface buckles. Various nanotube diameters and nanoring diameters of both armchair and zigzag nanotori were relaxed at room temperature, and the equilibrated atomic configurations were inspected. This study uses the coordinate parameter, which illustrates the atomic arrangement around each atom, as an indicator of buckles to avoid misjudgment caused by transient or thermal disturbance. For each nanotube diameter, there exists a critical nanoring diameter beyond which the perfect carbon nanotori can form. This study examines the binding potential energy and deformation energy of the relaxed nanotorus model, showing that the critical nanoring diameter cannot be easily predicted through critical energy consideration because buckling is a form of structural instability. Results show that the structural stability of a perfect nanoring primarily depends on the nanotube diameter and nanoring diameter, whereas its chirality has little effect, and one empirical relation is fitted to determine the critical nanoring diameters.
Critical effect of spin-dependent transport in a tunnel barrier on enhanced Hanle-type signals observed in three-terminal geometry
Authors: Uemura Tetsuya , Kondo Kenji , Fujisawa Jun , Matsuda Ken-ichi , Yamamoto Masafumi
Published: September 2012

The MgO thickness dependence of Hanle signals in Co50Fe50/MgO/n-Si tunnel junctions was investigated using a three-terminal geometry. The observed Hanle signal is several orders of magnitude stronger than the predicted value by conventional theory as reported in many literatures. Furthermore, the magnitude of the spin signal depends on the junction resistance rather than the channel resistance, implying that the largest part of the observed Hanle signal is not caused by spin accumulation in the semiconductor region. A possible origin of the observed strong Hanle signal is due to a modulation of the tunneling resistance by a magnetic field, which is induced by the spin precession in localized states formed in the vicinity of the Co50Fe50/MgO interface.
Creeping of minor hysteresis loops in Co thin films
Authors: Meilikhov E. Z. , Farzetdinova R. M.
Published: September 2012

In the framework of the Kolmogorov crystallization model, the non-repeatability of successive remagnetization cycles for ultrathin Co/M (M = Pt, Pd, Au) films is considered. That model has been shown to be suitable for describing magnetic relaxation processes in such systems with a “memory.” To this end some additional elements should be included in the model: it is necessary (i) to take into account that every cycle starts from the state left “heritably” by the preceding state and (ii) to suppose that the velocity of the new magnetic phase expansion depends on the cycle number. In the framework of such a model, we have succeeded to outline adequately (including quantitative description) all features of the successive magnetic relaxation cycles along with the astonishing effect of the cumulative growth of minor hysteresis loops.
Approaching intrinsic performance in ultra-thin silicon nitride drum resonators
Authors: Adiga V. P. , Ilic B. , Barton R. A. , Wilson-Rae I. , Craighead H. G. , Parpia J. M.
Published: September 2012

We have fabricated circular silicon nitride drums of varying diameter (20 μm to 1 mm) and thickness (15 nm–75 nm) using electron beam lithography and measured the dissipation (Q−1) of these amorphous silicon nitride resonators using optical interferometric detection. We observe that the dissipation is strongly dependent on mode type for relatively large, thick membranes as predicted by the current models of dissipation due to clamping loss. However, this dependence is drastically reduced for smaller or thinner resonators, with thinner resonators showing higher quality factors, for low order modes. Highest quality factors that can be reached for these thin resonators seems be limited by an intrinsic mechanism and scales linearly with the diameter of the membrane. Our results are promising for mass sensing and optomechanical applications where low mass and high Qs are desirable.
Performance of a permanent-magnet helicon source at 27 and 13 MHz
Authors: Chen Francis F.
Published: September 2012

A small helicon source is used to create dense plasma and inject it into a large chamber. A permanent magnet is used for the dc magnetic field (B-field), making the system very simple and compact. Though theory predicts that better antenna coupling will occur at 27.12 MHz, it was found that 13.56 MHz surprisingly gives even higher density due to practical effects not included in theory. Complete density n and electron temperature Te profiles are measured at three distances below the source. The plasma inside the source is also measured with a special probe, even under the antenna. The density there is lower than expected because the plasma created is immediately ejected, filling the experimental chamber. The advantage of helicons over inductively coupled plasmas (with no B-field) increases with RF power. At high B-fields, edge ionization by the Trivelpiece-Gould mode can be seen. These results are useful for design of multiple-tube, large-area helicon sources for plasma etching and deposition because problems are encountered which cannot be foreseen by theory alone.
Quasi-bichromatic laser for a lin⊥lin coherent population trapping clock produced by vertical-cavity surface-emitting lasers
Authors: Yun Peter , Tan Bozhong , Deng Wei , Yang Jing , Gu Sihong
Published: September 2012

With two vertical-cavity surface-emitting lasers working under the master-slave sideband injection-locking configuration, we have realized a quasi-bichromatic laser beam with residual phase noise Δϕ2 < 0.282 rad2. The two wanted frequency components share more than 96% power of the beam. With the realized beam, we have carried out coherent population trapping (CPT) resonance experiment with 87Rb in the lin⊥lin CPT scheme, and recorded CPT resonance signal with contrast of 60%. Such laser system is promising to realize a lin⊥lin CPT clock with high performance and low power consumption.
Magnetic reconnection in space
Authors: Boozer Allen H.
Published: September 2012

Models of magnetic reconnection in space plasmas generally consider only a segment of the magnetic field lines. The consideration of only a segment of the lines is shown to lead to paradoxical results in which reconnection can be impossible even in a magnetic field constrained to be curl free or can be at an Alfvén rate even when the plasma is a perfect conductor. A model of reconnecting magnetic fields is developed which shows the smallness of the interdiffusion distance δd of magnetic field lines does not limit the speed of reconnection but does provide a reconnection trigger. When the reconnection region has a natural length Lr, the spatial scale of the gradient of magnetic field across the magnetic field lines must reach Lg≈0.3Lr/ln(Lr/δd) for fast reconnection to be triggered, which implies a current density j≈B/μ0Lg that is far lower than that usually thought required for fast reconnection. The relation between magnetic reconnection in space and in toroidal laboratory plasmas is also discussed.
Giant magnetocaloric effect in magnetically frustrated EuHo2O4 and EuDy2O4 compounds
Authors: Midya A. , Khan N. , Bhoi D. , Mandal P.
Published: September 2012

We have investigated the magnetic and magnetocaloric properties of EuHo2O4 and EuDy2O4 by magnetization and heat capacity measurements down to 2 K. These compounds undergo a field-induced antiferromagnetic to ferromagnetic transition and exhibit a huge entropy change. For a field change of 0-8 T, the maximum magnetic entropy and adiabatic temperature changes are 30 (25) J kg−1 K−1 and 12.7 (16) K, respectively, and the corresponding value of refrigerant capacity is 540 (415) J kg−1 for EuHo2O4 (EuDy2O4). These magnetocaloric parameters also remain large down to lowest temperature measured and are even larger than that for some of the potential magnetic refrigerants reported in the same temperature range. Moreover, these materials are highly insulating and exhibit no thermal and field hysteresis, fulfilling the necessary conditions for a good magnetic refrigerant in the low-temperature region.
Giant electrocaloric effect in ferroelectric poly(vinylidenefluoride-trifluoroethylene) copolymers near a first-order ferroelectric transition
Authors: Li Xinyu , Qian Xiao-Shi , Gu Haiming , Chen Xiangzhong , Lu S. G. , Lin Minren , Bateman Fred , Zhang Q. M.
Published: September 2012

We present directly measured electrocaloric effect (ECE) from the poly(vinylidenefluoride-trifluoroethylene) 65/35 mol. % copolymer. The data reveal a large difference in the ECE between that measured in applying and in removing the electric field. The difference is significantly reduced by modifying the copolymer with 20 Mrad of high energy electron irradiation. Moreover, an isothermal entropy change ΔSint = 160 J kg−1 K−1 and an adiabatic temperature change ΔTint = 35 °C can be induced in the irradiated copolymer. These results demonstrate the promise of achieving a significant ECE in ferroelectric polymers near first-order ferroelectric-paraelectric transition where multiple intermediate phases can exist.
Specular Vision-Touch Synaesthesia: Two Reference Frames
Authors: White Rebekah C , Davies Anne M Aimola
Published: September 2012

Two subtypes of vision-touch synaesthesia (VTS) have been identified. For anatomical VTS, sight of touch on another person elicits synaesthetic tactile sensation at the same location on the observer's own body (eg viewed touch on the left cheek elicits sensation on the observer's left cheek). For specular VTS, sight of touch on another person elicits synaesthetic tactile sensation at the mirror-reflected location (eg viewed touch on the left cheek elicits sensation on the observer's right cheek). Here we report two distinctly different patterns of sensation within the specular subtype. Both participants experienced synaesthetic tactile sensation on their right hand when they viewed unidirectional brushstrokes administered to a prosthetic left hand (positioned with fingers pointing toward the participant), but the direction of sensation matched the viewed touch in a hand-centred (spatial) reference frame for RS and in an external (viewer-centred) reference frame for NC. Competing reference frames affect how individuals with specular VTS experience synaesthetic tactile sensation.
The lizard fauna of litter mats in the stony desert of the southern Northern Territory
Authors: McDonald Peter J. , Pavey Chris R. , Fyfe Greg
Published: September 2012

The formation of Australia’s stony deserts 2–4 million years ago will have reduced the availability of suitable habitat for lizards extant at that time, particularly for fossorial species. For such taxa, mats of litter, which form underneath woody vegetation, may offer the only suitable refuge sites in a greater matrix of unsuitable stony and compacted clay habitat. The integrity of litter mats in Australia’s stony deserts is potentially threatened by trampling by large introduced herbivores and by surface flows during flood events. Here we assess the importance of litter mats as habitat for lizards in these stony deserts and determine the suitability of the mats in relation to disturbance regimes. We surveyed 85 sites in the stony desert in the extreme south of the Northern Territory, using hand-raking as the sampling technique. We located 85 individuals of eight lizard species from three families, including 18 individuals of the nationally vulnerable monotypic pygopodid Ophidiocephalus taeniatus, establishing the significance of this limited microhabitat. Lizards were located underneath mats produced from the litterfall of four species of Acacia shrubs, though were not evenly distributed across these four mat types. Our results also provide the first evidence of the impact of large introduced herbivores on the suitability of litter mats. Although this was not statistically significant, lizards were more likely to be located at sites without disturbance from large herbivores, and were located only under individual mats that exhibited no sign of disturbance.
Structural evolution of the membrane-coating module of the nuclear pore complex
Authors: Liu Xiaoping , Mitchell Jana M. , Wozniak Richard W. , Blobel Günter , Fan Jie
Published: September 2012

The coatomer module of the nuclear pore complex borders the cylinder-like nuclear pore-membrane domain of the nuclear envelope. In evolution, a single coatomer module increases in size from hetero-heptamer (
Saccharomyces cerevisiae
) to hetero-octamer (
Schizosaccharomyces pombe
) to hetero-nonamer (Metazoa). Notably, the heptamer–octamer transition proceeds through the acquisition of the nucleoporin Nup37. How Nup37 contacts the heptamer remained unknown. Using recombinant nucleoporins, we show that Sp-Nup37 specifically binds the Sp-Nup120 member of the hetero-heptamer but does not bind an Sc-Nup120 homolog. To elucidate the Nup37–Nup120 interaction at the atomic level, we carried out crystallographic analyses of Sp-Nup37 alone and in a complex with an N-terminal, ∼110-kDa fragment of Sp-Nup120 comprising residues 1–950. Corroborating structural predictions, we determined that Nup37 folds into a seven-bladed β-propeller. Several disordered surface regions of the Nup37 β-propeller assume structure when bound to Sp-Nup120. The N-terminal domain of Sp-Nup120
1–950
also folds into a seven-bladed propeller with a markedly protruding 6D–7A insert and is followed by a contorted helical domain. Conspicuously, this 6D–7A insert contains an extension of 50 residues which also is highly conserved in Metazoa but is absent in Sc-Nup120. Strikingly, numerous contacts with the Nup37 β-propeller are located on this extension of the 6D–7A insert. Another contact region is situated toward the end of the helical region of Sp-Nup120
1–950
. Our findings provide information about the evolution and the assembly of the coatomer module of the nuclear pore complex.
On Kähler structures over symmetric products of a Riemann surface
Authors: Biswas Indranil
Published: September 2012

Given a positive integer

n
n

and a compact connected Riemann surface

X
X

, we prove that the symmetric product

S
n

(
X
)

S^n(X)

admits a Kähler form of nonnegative holomorphic bisectional curvature if and only if

genus
(
X
)

≤

1

\text {genus}(X)\, \leq \, 1

. If

n
n

is greater than or equal to the gonality of

X
X

, we prove that

S
n

(
X
)

S^n(X)

does not admit any Kähler form of nonpositive holomorphic sectional curvature. In particular, if

X
X

is hyperelliptic, then

S
n

(
X
)

S^n(X)

admits a Kähler form of nonpositive holomorphic sectional curvature if and only if

n

=

1

≤

genus
(
X
)

n\,=\,1\, \leq \, \text {genus}(X)

.
Retinal horizontal cells lackingRb1sustain persistent DNA damage and survive as polyploid giant cells
Authors: Donovan Stacy L. , Corbo Joseph C.
Published: September 2012

The retinoblastoma tumor susceptibility gene, Rb1, is a key regulator of the cell cycle, and mutations in this gene have been found in many human cancers. Prior studies showed that retina-specific knockout of Rb1 in the mouse results in the formation of abnormally large horizontal cells, but the development, fate, and genomic status of these cells remain unknown. In this study, we conditionally inactivate Rb1 in early retinal progenitors and show that the loss of Rb1 leads to the rapid degeneration of most retinal cells except horizontal cells, which persist as giant cells with aberrant centrosome content, DNA damage, and polyploidy/aneuploidy. We observed inappropriate cell cycle entry of Rb1-deficient horizontal cells during the first postnatal weeks, which dropped off abruptly by P30. Despite extensive DNA damage in Rb1-deficient horizontal cells, these cells can still enter mitosis. Adult Rb1-deficient horizontal cells display elevated DNA content (5N–34N) that varied continuously, suggesting the presence of aneuploidy. We also found evidence of supernumerary and disoriented centrosomes in a rare population of mitotic cells in the mutant retinas. Overall our data demonstrate that horizontal cells are a remarkably robust cell type and can survive for months despite extensive DNA damage and elevated genome content.
CTTNBP2, but not CTTNBP2NL, regulates dendritic spinogenesis and synaptic distribution of the striatin–PP2A complex
Authors: Chen Yi-Kai , Chen Chiung-Ya , Hu Hsiao-Tang , Hsueh Yi-Ping
Published: September 2012

Cortactin-binding protein 2 (CTTNBP2) interacts with cortactin to regulate cortactin mobility and control dendritic spine formation. CTTNBP2 has also been associated with autistic spectrum disorder. The regulation of dendritic spinogenesis could explain the association of CTTNBP2 with autism. Sequence comparison has indicated that CTTNBP2 N-terminal–like protein (CTTNBP2NL) is a CTTNBP2 homologue. To confirm the specific effect of CTTNBP2 on dendritic spinogenesis, here we investigate whether CTTNBP2NL has a similar function to CTTNBP2. Although both CTTNBP2 and CTTNBP2NL interact with cortactin, CTTNBP2NL is associated with stress fibers, whereas CTTNBP2 is distributed to the cortex and intracellular puncta. We also provide evidence that CTTNBP2, but not CTTNBP2NL, is predominantly expressed in the brain. CTTNBP2NL does not show any activity in the regulation of dendritic spinogenesis. In addition to spine morphology, CTTNBP2 is also found to regulate the synaptic distribution of striatin and zinedin (the regulatory B subunits of protein phosphatase 2A [PP2A]), which interact with CTTNBP2NL in HEK293 cells. The association between CTTNBP2 and striatin/zinedin suggests that CTTNBP2 targets the PP2A complex to dendritic spines. Thus we propose that the interactions of CTTNBP2 and cortactin and the PP2A complex regulate spine morphogenesis and synaptic signaling.
SpolPred: rapid and accurate prediction of Mycobacterium tuberculosis spoligotypes from short genomic sequences
Authors: Coll Francesc , Mallard Kim , Preston Mark D. , Bentley Stephen , Parkhill Julian , McNerney Ruth , Martin Nigel , Clark Taane G.
Published: September 2012

Summary: Spoligotyping is a well-established genotyping technique based on the presence of unique DNA sequences in Mycobacterium tuberculosis (Mtb), the causal agent of tuberculosis disease (TB). Although advances in sequencing technologies are leading to whole-genome bacterial characterization, tens of thousands of isolates have been spoligotyped, giving a global view of Mtb strain diversity. To bridge the gap, we have developed SpolPred, a software to predict the spoligotype from raw sequence reads. Our approach is compared with experimentally and de novo assembly determined strain types in a set of 44 Mtb isolates. In silico and experimental results are identical for almost all isolates (39/44). However, SpolPred detected five experimentally false spoligotypes and was more accurate and faster than the assembling strategy. Application of SpolPred to an additional seven isolates with no laboratory data led to types that clustered with identical experimental types in a phylogenetic analysis using single-nucleotide polymorphisms. Our results demonstrate the usefulness of the tool and its role in revealing experimental limitations.

Availability and implementation: SpolPred is written in C and is available from www.pathogenseq.org/spolpred.

Contact:  francesc.coll@lshtm.ac.uk

Supplementary information:  Supplementary data are available at Bioinformatics Online.
Development of Tools for the Biochemical Characterization of the Symbiotic Receptor-Like Kinase DMI2
Authors: Riely Brendan K. , Larrainzar Estíbaliz , Haney Cara H. , Mun Jeong-Hwan , Gil-Quintana Erena , González Esther M. , Yu Hee-Ju , Tricoli David , Ehrhardt David W. , Long Sharon R. , Cook Douglas R.
Published: September 2012

The Medicago truncatula DMI2 gene encodes a leucine-rich repeat receptor-like kinase that is essential for symbiosis with nitrogen-fixing rhizobia. While phenotypic analyses have provided a description for the host's responses mediated by DMI2, a lack of tools for in vivo biochemical analysis has hampered efforts to elucidate the mechanisms by which DMI2 mediates symbiotic signal transduction. Here, we report stably transformed M. truncatula lines that express a genomic DMI2 construct that is fused to a dual-affinity tag containing three copies of the hemagglutinin epitope and a single StrepII tag (gDMI2:HAST). gDMI2: HAST complements the dmi2-1 mutation, and transgenic plants expressing this construct behave similarly to wild-type plants. We show that the expression patterns of gDMI2:HAST recapitulate those of endogenous DMI2 and that we can detect and purify DMI2:HAST from microsomal root and nodule extracts. Using this line, we show that DMI2 resides in a high–molecular weight complex, which is consistent with our observation that DMI2:GFP localizes to plasma membrane–associated puncta and cytoplasmic vesicles. We further demonstrate that Nod factor (NF) perception increases the abundance of DMI2 vesicles. These tools should be a valuable resource for the Medicago community to dissect the biochemical function of DMI2.
First Report of Erwinia amylovora on Firethorn (Pyracantha coccinea) and Mountainash (Sorbus sp.) in Turkey
Authors: Bastas K. K.
Published: September 2012

Fire blight, caused by the bacterium Erwinia amylovora, is a serious disease of apples (Malus spp.) and pears (Pyrus spp.) but can also infect many ornamental species in the Rosaceae family. In the summers of 2009 and 2010, leaf and shoot blight and reddish colored cankers were observed on firethorn (Pyracantha coccinea) and brown discolored leaves and necrotic stem lesions on mountain ash (Sorbus sp.) both from the landscape areas of Konya province. Investigation of these symptoms showed that in an 85-ha area, disease incidence was estimated at 1.5% and 1% on firethorn and mountain ash, respectively. Bacteria were consistently isolated from both leaf and lesions onto nutrient sucrose agar medium. Nine representative bacterial colonies from firethorn isolations and six from mountain ash isolations purified and characterized as gram-negative, rod-shaped, mucoid, fermentative, yellow-orange on Miller & Scroth medium, positive for levan formation and acetoin production, no growth at 36°C, positive for gelatin and esculin hydrolysis, and negative for indole, urease, oxidase, arginine dehydrolase, reduction of nitrate, and acid production from lactose and inositol (2). Two reference strains of E. amylovora (EaP28 and NCPPB 2791) obtained from culture collection at Selcuk University, Department of Plant Protection, Konya, Turkey, were used as positive controls. All strains induced a hypersensitive response in tobacco (Nicotiana tobaccum cv. White Burley) and produced ooze when stab inoculated on immature pear fruits. In addition, all strains and the references were identified as E. amylovora on the basis of a 1-kb DNA fragment amplification with a species-specific primer set, A/B (1) in PCR. Pathogenicity tests were performed by injecting a bacterial suspension (108 CFU ml–1) into the shoot tips of 3-year-old firethorn and mountain ash seedlings, resulting in leaf and shoot blight symptoms observed 10 to 15 days after inoculation. No symptoms were observed on control plants treated with sterile water. E. amylovora was positively reisolated from leaf and shoot lesions from the inoculated seedlings and identified as described above. To our knowledge, this is the first report of E. amylovora on P. coccinea and Sorbus sp. in Turkey.

References: (1) S. Bereswill et al. Appl. Environ. Microbiol. 58:3522, 1992 (2) A. L. Jones and K. Geider. Page 40 in: Laboratory Guide for Identification of Plant Pathogenic Bacteria, 2001.
First Report of Fire Blight Disease on Blackberry in Turkey
Authors: Bastas K. K. , Sahin F.
Published: September 2012

During 2008 and 2009, a new disease on blackberry (Rubus fruticosus cv. Chester) causing leaf and shoot blight and cankers with brown discoloration of necrotic tissues on mature branches was observed in Isparta and Konya provinces of Turkey. Disease incidence was estimated to be 4% for the two years. Isolations were made from lesions on leaves and shoots on nutrient sucrose agar (NSA) medium. Bacteria consistently isolated from the diseased tissues were identified on the basis of biochemical, physiological (2), and molecular tests (1). Eleven representative bacterial strains were gram-negative, rod-shaped, mucoid, fermentative, yellow-orange on Miller and Scroth (MS) medium, positive for levan formation and acetoin production, no growth at 36°C, positive for gelatin hydrolysis, and negative for esculin hydrolysis, indole, urease, catalase, oxidase, arginine dehydrolase, reduction of nitrate, acid production from lactose, and inositol. Two reference strains of Erwinia amylovora (EaP28 and NCPPB 2791) obtained from the culture collection unit of Selcuk University were used as positive controls. All strains induced a hypersensitive response in tobacco (Nicotiana tobaccum cv White Burley) 24 h after inoculation with a 108 CFU/ml bacterial suspension in water. All strains were identified as E. amylovora using the species-specific primers set A/B (1), which amplified a 1-kb DNA fragment in PCR, and fatty acid methyl ester (FAME) profiles determined by Sherlock Microbial Identification System software (TSBA 6 v. 6.00; Microbial ID, Newark, DE) with similarity indices ranging from of 79 to 99%. Pathogenicity was confirmed by injecting bacterial suspensions (108 CFU/ml–1) in sterile distilled water into the shoot tips of 2-year-old R. fruticosus cv. Chester and the first blighting symptoms were observed on leaves within 3 days and also 10 days later after inoculation on shoots. Sterile distilled water was used as a negative control. No symptoms were observed on control plants. All tests were repeated three times. The bacterium was reisolated from inoculated plants and identified as. E. amylovora. To our knowledge, this is the first report of E. amylovora on blackberry in Turkey. Phytosanitary measures are needed to prevent any further spread of the bacterium to new blackberry areas.

References: (1) S. Bereswill et al. App. Environ. Microbiol. 58:3522, 1992. (2) A. L. Jones and K. Geider. Lab. Guide for Identification of Plant Pathological Bacteria, 40, 2001.
An Analysis of the Genomic Variability of the Phytopathogenic Mollicute Spiroplasma kunkelii
Authors: Carpane Pablo , Melcher Ulrich , Wayadande Astri , de la Paz Gimenez Pecci María , Laguna Graciela , Dolezal William , Fletcher Jacqueline
Published: September 2012

Corn stunt disease has become a factor limiting maize production in some areas of the Americas in recent years. Although resistant maize genotypes have been developed in the past, this resistance has been unstable over time or in some geographical locations. To better understand disease components that could affect the stability of host resistance, we assessed the genome variability of the etiologic agent, Spiroplasma kunkelii. Isolates were obtained from a number of areas, and characterized molecularly by amplification of several regions of the spiroplasma chromosome and sequencing of specific gene fragments. The degree of polymorphism between isolates of different geographic origins was low, and the level of genomic variability was similar within isolates of different countries. Polymorphism among isolates was found in viral insertions and in the sequence of Skarp, a gene that encodes a membrane protein implicated in attachment to insect cells. The results suggest that the genome composition of this species is highly conserved among isolates. Hence, it is unlikely that the instability of maize resistance is due to generation of new pathotypes of S. kunkelii. Instead, other components of this complex pathosystem could account for the breakdown of resistance.