bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel combination of DLS-optical microrheology and low frequency Raman spectroscopy to reveal underlying biopolymer self-assembly and gelation mechanisms
Authors: Amin S. , Blake S. , Kenyon S. M. , Kennel R. C. , Lewis E. N.
Published: December 2014

The connectivity between gelation and increasing water confinement and structuring within nanopores of a thermally induced gel is demonstrated for the first time through low frequency Raman spectroscopy and optical microrheology measurements. Specifically, the work confirms that increased ordering of individual water molecules can be observed during the gelation of agarose upon cooling. More importantly, it illustrates the ability of the two techniques to provide new insights and a more direct link between intermolecular interactions/microstructure and evolving rheological response in gelling systems.
Recursive polarization of nuclear spins in diamond at arbitrary magnetic fields
Authors: Pagliero Daniela , Laraoui Abdelghani , Henshaw Jacob D. , Meriles Carlos A.
Published: December 2014

We introduce an alternate route to dynamically polarize the nuclear spin host of nitrogen-vacancy (NV) centers in diamond. Our approach articulates optical, microwave, and radio-frequency pulses to recursively transfer spin polarization from the NV electronic spin. Using two complementary variants of the same underlying principle, we demonstrate nitrogen nuclear spin initialization approaching 80% at room temperature both in ensemble and single NV centers. Unlike existing schemes, our approach does not rely on level anti-crossings and is thus applicable at arbitrary magnetic fields. This versatility should prove useful in applications ranging from nanoscale metrology to sensitivity-enhanced NMR.
Mechanical 144 GHz beam steering with all-metallic epsilon-near-zero lens antenna
Authors: Pacheco-Peña V. , Torres V. , Orazbayev B. , Beruete M. , Navarro-Cía M. , Sorolla M. , Engheta N.
Published: December 2014

An all-metallic steerable beam antenna composed of an ε-near-zero (ENZ) metamaterial lens is experimentally demonstrated at 144 GHz (λ0 = 2.083 mm). The ENZ lens is realized by an array of narrow hollow rectangular waveguides working just near and above the cut-off of the TE10 mode. The lens focal arc on the xz-plane is initially estimated analytically as well as numerically and compared with experimental results demonstrating good agreement. Next, a flange-ended WR-6.5 waveguide is placed along the lens focal arc to evaluate the ENZ-lens antenna steerability. A gain scan loss below 3 dB is achieved for angles up to ±15°.
Two-fluid turbulence including electron inertia
Authors: Andrés Nahuel , Gonzalez Carlos , Martin Luis , Dmitruk Pablo , Gómez Daniel
Published: December 2014

We present a full two-fluid magnetohydrodynamic (MHD) description for a completely ionized hydrogen plasma, retaining the effects of the Hall current, electron pressure, and electron inertia. According to this description, each plasma species introduces a new spatial scale: the ion inertial length λi and the electron inertial length λe, which are not present in the traditional MHD description. In the present paper, we seek for possible changes in the energy power spectrum in fully developed turbulent regimes, using numerical simulations of the two-fluid equations in two-and-a-half dimensions. We have been able to reproduce different scaling laws in different spectral ranges, as it has been observed in the solar wind for the magnetic energy spectrum. At the smallest wavenumbers where plain MHD is valid, we obtain an inertial range following a Kolmogorov k−5∕3 law. For intermediate wavenumbers such that λi−1≪k≪λe−1, the spectrum is modified to a k−7∕3 power-law, as has also been obtained for Hall-MHD neglecting electron inertia terms. When electron inertia is retained, a new spectral region given by k>λe−1 arises. The power spectrum for magnetic energy in this region is given by a k−11∕3 power law. Finally, when the terms of electron inertia are retained, we study the self-consistent electric field. Our results are discussed and compared with those obtained in the solar wind observations and previous simulations.
Development of a semi-adiabatic isoperibol solution calorimeter
Authors: Venkata Krishnan R. , Jogeswararao G. , Parthasarathy R. , Premalatha S. , Prabhakar Rao J. , Gunasekaran G. , Ananthasivan K.
Published: December 2014

A semi-adiabatic isoperibol solution calorimeter has been indigenously developed. The measurement system comprises modules for sensitive temperature measurement probe, signal processing, data collection, and joule calibration. The sensitivity of the temperature measurement module was enhanced by using a sensitive thermistor coupled with a lock-in amplifier based signal processor. A microcontroller coordinates the operation and control of these modules. The latter in turn is controlled through personal computer (PC) based custom made software developed with LabView. An innovative summing amplifier concept was used to cancel out the base resistance of the thermistor. The latter was placed in the dewar. The temperature calibration was carried out with a standard platinum resistance (PT100) sensor coupled with an 8½ digit multimeter. The water equivalent of this calorimeter was determined by using electrical calibration with the joule calibrator. The experimentally measured values of the quantum of heat were validated by measuring heats of dissolution of pure KCl (for endotherm) and tris (hydroxyl methyl) amino-methane (for exotherm). The uncertainity in the measurements was found to be within ±3%.
Enhanced hydrogen evolution rates at high pH with a colloidal cadmium sulphide–platinum hybrid system
Authors: Schneider Julian , Vaneski Aleksandar , Pesch Georg R. , Susha Andrei S. , Yang Teoh Wey , Rogach Andrey L.
Published: December 2014

We demonstrate enhanced hydrogen generation rates at high pH using colloidal cadmium sulphide nanorods decorated with Pt nanoparticles. We introduce a simplified procedure for the decoration and subsequent hydrogen generation, reducing both the number of working steps and the materials costs. Different Pt precursor concentrations were tested to reveal the optimal conditions for the efficient hydrogen evolution. A sharp increase in hydrogen evolution rates was measured at pH 13 and above, a condition at which the surface charge transfer was efficiently mediated by the formation of hydroxyl radicals and further consumption by the sacrificial triethanolamine hole scavenger.
Deep-level transient spectroscopy of Al/a-Si:H/c-Si structures for heterojunction solar cell applications
Authors: Simoen E. , Ferro V. , O'Sullivan B. J.
Published: December 2014

A Deep-Level Transient Spectroscopy study is performed on Metal-Insulator-Semiconductor capacitors with a 70 nm amorphous silicon (a-Si:H) passivation layer, in order to study the electrically active defects present at the n- or p-type crystalline silicon (c-Si)/a-Si:H heterojunction. Trap filling kinetics identify two types of traps, namely, Pb0 dangling bond centers at the Si(100) interface and similar D centers in the a-Si:H, which are in close proximity to the interface and giving rise to a dominant peak around silicon midgap. The distinction between both kinds of deep levels is based on the carrier capture behavior, which is more point-defect-like for the Pb0 centers and varies according to the logarithm of the voltage pulse duration for the D defects, indicating capture of majority carriers from the substrate by tunneling into a-Si:H, the densities of which are correlated with capacitance-voltage measurements. This directly demonstrates that the recombination properties of the c-Si/a-Si:H interface are both determined by Pb0 and D defect states.
Quantized spin waves in single Co/Pt dots detected by anomalous Hall effect based ferromagnetic resonance
Authors: Kikuchi N. , Furuta M. , Okamoto S. , Kitakami O. , Shimatsu T.
Published: December 2014

Anomalous Hall effect (AHE) based ferromagnetic resonance (FMR) measurements were carried out on perpendicularly magnetized Co/Pt multilayer single dots of 0.4–3 μm in diameter. The resonance behavior was measured by detecting the decrease of perpendicular magnetization component due to magnetization precession. Resonance behavior was observed as a clear decrease of Hall voltages, and the obtained resonance fields were consistent with the results of vector-network-analyzer FMR. Spin-waves with cylindrical symmetry became significant by decreasing the dot diameter, and quantized multiple resonances were observed in the dot of 0.4 μm in diameter. The AHE based FMR proposed here is a powerful method to approach magnetization dynamics including spin waves and non-linear behavior excited in a finite nanostructure.
Goos-Hänchen effect and bending of spin wave beams in thin magnetic films
Authors: Gruszecki P. , Romero-Vivas J. , Dadoenkova Yu. S. , Dadoenkova N. N. , Lyubchanskii I. L. , Krawczyk M.
Published: December 2014

For magnon spintronic applications, the detailed knowledge of spin wave (SW) beam dispersion, transmission (reflection) of SWs passing through (reflected from) interfaces, or borders or the scattering of SWs by inhomogeneities is crucial. These wave properties are decisive factors on the usefulness of a particular device. Here, we demonstrate, using micromagnetic simulations supported by an analytical model, that the Goos-Hänchen (GH) shift exists for SW reflecting from thin film edge and that with the effect becomes observable. We show that this effect will exist for a broad range of frequencies in the dipole-exchange range, with the magnetization degree of pinning at the film edge as the crucial parameter, whatever its nature. Moreover, we have also found that the GH effect can be accompanied or even dominating by a bending of the SW beam due to the inhomogeneity of the internal magnetic field. This inhomogeneity, created by demagnetizing field taking place at the film edge, causes gradual change of SWs refractive index. The refraction of the SW beams by the non-uniformity of the magnetic field enables the exploration of graded index magnonics and metamaterial properties for the transmission and processing of information at nanoscale.
The role of residual charges in the repeatability of the dynamics of atmospheric pressure room temperature plasma plume
Authors: Wu S. , Lu X.
Published: December 2014

To better understand the role of residual electrons in the repeatability of an atmospheric pressure plasma plume, the characteristics of a helium plasma jet from the 1st, 2nd,… until the repeatable discharge pulse are investigated for the first time. It's found that the longest plasma plume is achieved in the 1st discharge pulse. The length of the plasma plume becomes shorter and shorter and reaches a constant value in the 3rd discharge pulse and keeps the same for the following pulses. The dynamics of the 1st discharge pulse show that the plasma bullet appears random in nature. Two photomultiplier tubes are used to distinguish the two potential factors that could result in the stochastic dynamics of the plasma bullet, i.e., stochastic ignition of the plasma and the stochastic propagation velocity. The results show that the stochastic propagation velocity occurs only in the 1st and the 2nd discharge pulses, while the stochastic ignition of the plasma presents until the 100th pulse. The dynamics of the plasma propagation become repeatable after about 100 pulses. Detail analysis shows that the repeatability of plasma bullet is due to the residual electrons density. The residual electron density of 109 cm−3 or higher is needed for repeatable discharges mode.
Large-sized out-of-plane stretchable electrodes based on poly-dimethylsiloxane substrate
Authors: Chou Namsun , Lee Jongho , Kim Sohee
Published: December 2014

This paper describes a reliable fabrication method of stretchable electrodes based on poly-dimethylsiloxane (PDMS) substrate. The electrode traces and pads were formed in out-of-plane structures to improve the flexibility and stretchability of the electrode array. The suspended traces and pads were attached to the PDMS substrate via parylene posts that were located nearby the traces and under the pads. As only conventional micro-electro-mechanical systems techniques were used, the out-of-plane electrode arrays were clearly fabricated at wafer level with high yield and reliability. Also, bi-layer out-of-plane electrodes were formed through additional fabrication steps in addition to mono-layer out-of-plane electrodes. The mechanical characteristics such as the stretchability, flexibility, and foldability of the fabricated electrodes were evaluated, resulting in stable electrical connection of the metal traces with up to 32.4% strain and up to 360° twist angle over 25 mm. The durability in stretched condition was validated by cyclic stretch test with 10% and 20% strain, resulting in electrical disconnection at 8600 cycles when subjected to 20% strain. From these results, it is concluded that the proposed fabrication method produced highly reliable, out-of-plane and stretchable electrodes, which would be used in various flexible and stretchable electronics applications.
Laser doping for ohmic contacts in n-type Ge
Authors: Chiodi F. , Chepelianskii A. D. , Gardès C. , Hallais G. , Bouchier D. , Débarre D.
Published: December 2014

We achieved ohmic contacts down to 5 K on standard n-doped Ge samples by creating a strongly doped thin Ge layer between the metallic contacts and the Ge substrate. Thanks to the laser doping technique used, gas immersion laser doping, we could attain extremely large doping levels above the solubility limit, and thus reduce the metal/doped Ge contact resistance. We tested independently the influence of the doping concentration and doped layer thickness and showed that the ohmic contact improves when increasing the doping level and is not affected when changing the doped thickness. Furthermore, we characterised the doped Ge/Ge contact, showing that at high doping its contact resistance is the dominant contribution to the total contact resistance.
Frequency jumps in single chip microwave LC oscillators
Authors: Gualco Gabriele , Grisi Marco , Boero Giovanni
Published: December 2014

We report on the experimental observation of oscillation frequency jumps in microwave LC oscillators fabricated using standard complementary metal-oxide-semiconductor technologies. The LC oscillators, operating at a frequency of about 20 GHz, consist of a single turn planar coil, a metal-oxide-metal capacitor, and two cross-coupled metal-oxide-semiconductor field effect transistors used as negative resistance network. At 300 K as well as at 77 K, the oscillation frequency is a continuous function of the oscillator bias voltage. At 4 K, frequency jumps as large as 30 MHz are experimentally observed. This behavior is tentatively attributed to the emission and capture of single electrons from defects and dopant atoms.
Visible light illumination-induced phase transition to the intermediate states between the metallic and insulating states for the LaAlO3/SrTiO3 interfaces
Authors: Lei Y. , Sun J. R.
Published: December 2014

Photoexcitation usually drives the LaAlO3/SrTiO3 interface from the insulating state into a totally metallic state, without experiencing any intermediate states. Here, we reported on an illumination-induced transition of the insulating LaAlO3(3uc)/SrTiO3 interface to a series of state between a totally insulating state and a totally metallic state. We found that appropriate light illumination can cause an insulator-to-semiconductor transition in the temperature range above ∼150 K and an insulator-to-metal transition below ∼60 K, while the original state recovers immediately after the removal of the illumination, without persistent photoconductivity as previously reported. Moreover, a remarkable resistive anomaly corresponding to the structural transition of SrTiO3 at ∼105 K appears, indicating a phase-transition-induced carrier density change.
Enhancement of the electrical characteristics of metal-free phthalocyanine films using cold isostatic pressing
Authors: Matsushima Toshinori , Esaki Yu , Adachi Chihaya
Published: December 2014

Spatial gaps between grains and other grains, substrates, or electrodes in organic electronic devices are one of the causes of the reduction in the electrical characteristics. In this study, we demonstrate that cold isostatic pressing (CIP) is an effective method to crush the gaps and enhance the electrical characteristics. CIP of metal-free phthalocyanine (H2PC) films induced a decrease in the film thickness by 34%–40% because of the gap crush. The connection of smaller grains into a larger grain and planarization of the film surface were also observed in the CIP film. The crystal axes of the H2PC crystallites were rearranged from the a-axis to the c-axis of the α-phase crystal structure in a direction perpendicular to the substrate by CIP, indicating favorable hole injection and transport in this direction because of a better overlap of π orbitals. Thermally stimulated current measurements showed that deep hole traps disappeared and the total hole-trap density decreased after CIP. These CIP-induced changes of the film thicknesses, crystal axes and the hole traps lead to a marked increase in the hole mobility of the H2PC films from 2.0 × 10−7 to 4.0 × 10−4 cm2/V s by 2000 times in the perpendicular direction. We believe that these findings are important for unveiling the underlying carrier injection and transport mechanisms of organic films and for enhancing the performance of future organic electronic devices.
Thermal-cycling-dependent magnetostructural transitions in a Ge-free system Mn0.5Fe0.5Ni(Si,Al)
Authors: Zhang C. L. , Shi H. F. , Nie Y. G. , Ye E. J. , Han Z. D. , Wang D. H.
Published: December 2014

Magnetostructural transitions from low-temperature TiNiSi-type phases to high-temperature Ni2In-type phases had been observed in some MnCoGe-based and MnNiGe-based intermetallic systems. In this work, the TiNiSi-to-Ni2In-type magnetostructural transitions, which are associated with large changes in magnetization and large anisotropy lattice distortion, were obtained in a Ge-free system Mn0.5Fe0.5Ni(Si,Al) in the vicinity of room temperature. Thermal-cycling-dependent properties were observed in the as-prepared bulk polycrystalline samples. This phenomenon could be attributed to the presence of anisotropy internal stress and its release by spontaneously cracking across the thermally activated magnetostructural transitions.
Gelatin as a new humidity sensing material: Characterization and limitations
Authors: Shapardanis Steven , Hudpeth Mathew , Kaya Tolga
Published: December 2014

The goal of this work is to assert the utility of collagen and its denatured counterpart gelatin as cost-effective alternatives to existing sensing layers comprised of polymers. Rather than producing a material that will need to be discarded or recycled, collagen, as a by-product of the meat and leather industry, could be repurposed. This work examines the feasibility of using collagen as a sensing layer. Planar electrodes were patterned with lift-off process to work with the natural characteristics of gelatin by utilizing metal vapor deposition, spin coating, and photolithography. Characterization methods have also been optimized through the creation of specialized humidity chambers that isolate specific characteristics such as response time, accuracy, and hysteresis. Collagen-based sensors are found to have a sensitivity to moisture in the range of 0.065 pF/%RH. Diffusion characteristics were also analyzed with the diffusion coefficient found to be 2.5 × 10−5 cm2/s. Absorption and desorption times were found to be 20 seconds and 8 seconds, respectively. Hysteresis present in the data is attributed to temperature cross-sensitivity. Ultimately, the utility of collagen as a dielectric sensing material is, in part, due to its fibrous macrostructures as well its hydrophilic sites along the peptide chains. Gelatin was patterned between and below interdigitated copper electrodes and tested as a relative humidity sensor. This work shows that gelatin, which is inexpensive, widely available, and easy to process, can be an effective dielectric sensing polymer for capacitive-type relative humidity sensors.
Magnetic anisotropy of Au/Co/Au/MgO heterostructure: Role of the gold at the Co/MgO interface
Authors: Gladczuk L. , Aleshkevych P. , Lasek K. , Przyslupski P.
Published: December 2014

The influence of Au interlayer on the out-of-plane magnetic anisotropy of Au/Co/Au/MgO/Au heterostructures with ultra-thin Co wedge-shaped film was investigated by means of ferromagnetic resonance. It was found that introduction of a single Au monolayer enhances the surface anisotropy of the Co/MgO interface. An occurrence of a large perpendicular anisotropy with respect to the Co overlayer suggests that the largest contribution to the interface anisotropy energy originates from the Au/Co interface as a result of strong Au and Co orbitals hybridization.
Microstructural and ionic transport studies of hydrothermally synthesized lanthanum fluoride nanoparticles
Authors: Patro L. N. , Kamala Bharathi K. , Ravi Chandra Raju N.
Published: December 2014

This article presents the structural and transport characteristics of hydrothermally synthesized LaF3 nanoparticles with an average crystallite size of 35nm. The phase formation of the material is confirmed by both X-ray diffraction and transmission electron microscopy techniques. In addition, phase purity of the LaF3 nanoparticles is corroborated by micro-Raman spectroscopy studies. The complex impedance plots at different temperatures reveal that the conductivity is predominantly due to the intrinsic bulk grains and the conductivity relaxation is non-Debye in nature. The frequency variation of conductivity exhibits dispersion at higher frequencies that can be explained with the frame work of Almond-West formalism. The conduction process is controlled by the mobility of the charge carriers and the charge of transport of mobile fluoride ions occur through hopping mechanism. The scaling behavior of both frequency dependence of conductivity and complex impedance plots at different temperatures confirm that the relaxation mechanism of the mobile fluoride ions is independent of temperature.
Influence of spin injection on the critical current density in La0.7Sr0.3MnO3/La1.85Sr0.15CuO4 heterostructure
Authors: Zhang M. J. , Teng M. L. , Hao F. X. , Yin Y. W. , Li X. G. , Zeng Z.
Published: December 2014

The anisotropic polarized spin injection effect on the critical current density Jc of La0.7Sr0.3MnO3/La1.85Sr0.15CuO4 heterostructure is systematically investigated. It is found that the contribution of δTc pinning mechanism is enhanced with spin injection. The angle dependent Jc(θ) near H//c can be scaled by the Ginzburg-Landau (G-L) expression, while for H//ab the intrinsic pinning drives the data to deviate from the G-L fitting. The relative changes of Jc affected by spin injection show opposite variation trends with increasing fields for H//ab and H//c, which is probably related to the different suppressions of injected spins on different flux pinnings.
Synthesis, Characterisation, and Antifungal Activities of Novel Benzodiazaborines
Authors: Yang Jiyoung , Johnson Brandon J. , Letourneau Allan A. , Vogels Christopher M. , Decken Andreas , Baerlocher Felix J. , Westcott Stephen A.
Published: December 2014

Eight new fluoro- and methoxy-substituted benzodiazaborines have been prepared by a simple condensation reaction in high-to-excellent yields. All new compounds have been characterised by several physical methods, including X-ray diffraction studies on three examples. All new compounds were examined for antifungal activities against five species of potentially pathogenic fungi (Aspergillus niger, Aspergillus fumigatus, Rhizoctonia solani, Verticillium albo-atrum, and Verticillium dahliae). While substitution of the aromatic group derived from the 2-formylphenylboronic acid group had an effect on bioactivities, substitution on the parent thioamide C(=S)NH2 group of the starting thiosemicarbazide greatly reduced activities.
Comparison of forest burned areas in mainland China derived from MCD45A1 and data recorded in yearbooks from 2001 to 2011
Authors: Li Jianfeng , Song Yu , Huang Xin , Li Mengmeng
Published: December 2014

Forest burning, which emits large amounts of trace gases and particulate matter into the atmosphere, produces great impacts on air quality and climate change. In this study, the MODIS (Moderate-Resolution Imaging Spectroradiometer) burned area product (MCD45A1) and GlobCover land-cover product were integrated to estimate the forest burned areas in mainland China from 2001 to 2011. The results were compared with the official data from China Forestry Yearbooks and China Forestry Statistical Yearbooks. On the national scale, the MCD45A1 data were comparable with the official data. However, great gaps exist between the MCD45A1-derived provincial and regional forest burned areas and the corresponding values from the Forestry Statistical Yearbooks. In particular, the MCD45A1-derived areas were higher than the Forestry Statistical Yearbooks in north-east China and significantly lower in south-west China. Moreover, it was indicated that the MCD45A1 algorithm was unsuitable for retrieving the burned areas of small forest fires. Nevertheless, the MCD45A1 exhibited excellent performance in retrieving seasonal patterns of forest fire, with high fire occurrence in spring and autumn. On balance, more studies are required to assess and improve the MCD45A1 product and more precise data on forest burned areas in China are urgently needed.
Unveiling the morphology of the acetabulum in octopus suckers and its role in attachment
Authors: Tramacere Francesca , Pugno Nicola M. , Kuba Michael J. , Mazzolai Barbara
Published: December 2014

In recent years, the attachment mechanism of the octopus sucker has attracted the interest of scientists from different research areas, including biology, engineering, medicine and robotics. From a technological perspective, the main goal is to identify the underlying mechanisms involved in sucker attachment for use in the development of new generations of artificial devices and materials. Recently, the understanding of the morphology of the sucker has been significantly improved; however, the mechanisms that allow attachment remain largely unknown. In this work, we present new anatomical findings: specifically, a protuberance in the acetabular roof in five different octopus species; previously, this protuberance was identified by the authors inOctopus vulgaris. Moreover, we discuss the role of the protuberance and other anatomical structures in attachment with minimal energy consumption.
You are what you eat: diet-induced chemical crypsis in a coral-feeding reef fish
Authors: Brooker Rohan M. , Munday Philip L. , Chivers Douglas P. , Jones Geoffrey P.
Published: December 2014

The vast majority of research into the mechanisms of camouflage has focused on forms that confound visual perception. However, many organisms primarily interact with their surroundings using chemosensory systems and may have evolved mechanisms to ‘blend in’ with chemical components of their habitat. One potential mechanism is ‘chemical crypsis' via the sequestration of dietary elements, causing a consumer's odour to chemically match that of its prey. Here, we test the potential for chemical crypsis in the coral-feeding filefish,
Oxymonacanthus longirostris
, by examining olfactory discrimination in obligate coral-dwelling crabs and a predatory cod. The crabs, which inhabit the corals consumed by
O. longirostris
, were used as a bioassay to determine the effect of coral diet on fish odour. Crabs preferred the odour of filefish fed their preferred coral over the odour of filefish fed a non-preferred coral, suggesting coral-specific dietary elements that influence odour are sequestered. Crabs also exhibited a similar preference for the odour of filefish fed their preferred coral and odour directly from that coral, suggesting a close chemical match. In behavioural trials, predatory cod were less attracted to filefish odour when presented alongside the coral it had been fed on, suggesting diet can reduce detectability. This is, we believe, the first evidence of diet-induced chemical crypsis in a vertebrate.
PECTIN METHYLESTERASE48 Is Involved in Arabidopsis Pollen Grain Germination
Authors: Leroux Christelle , Bouton Sophie , Kiefer-Meyer Marie-Christine , Fabrice Tohnyui Ndinyanka , Mareck Alain , Guénin Stéphanie , Fournet Françoise , Ringli Christoph , Pelloux Jérôme , Driouich Azeddine , Lerouge Patrice , Lehner Arnaud , Mollet Jean-Claude
Published: December 2014

Germination of pollen grains is a crucial step in plant reproduction. However, the molecular mechanisms involved remain unclear. We investigated the role of PECTIN METHYLESTERASE48 (PME48), an enzyme implicated in the remodeling of pectins in Arabidopsis (Arabidopsis thaliana) pollen. A combination of functional genomics, gene expression, in vivo and in vitro pollen germination, immunolabeling, and biochemical analyses was used on wild-type and Atpme48 mutant plants. We showed that AtPME48 is specifically expressed in the male gametophyte and is the second most expressed PME in dry and imbibed pollen grains. Pollen grains from homozygous mutant lines displayed a significant delay in imbibition and germination in vitro and in vivo. Moreover, numerous pollen grains showed two tips emerging instead of one in the wild type. Immunolabeling and Fourier transform infrared analyses showed that the degree of methylesterification of the homogalacturonan was higher in pme48−/− pollen grains. In contrast, the PME activity was lower in pme48−/−, partly due to a reduction of PME48 activity revealed by zymogram. Interestingly, the wild-type phenotype was restored in pme48−/− with the optimum germination medium supplemented with 2.5 mm calcium chloride, suggesting that in the wild-type pollen, the weakly methylesterified homogalacturonan is a source of Ca2+ necessary for pollen germination. Although pollen-specific PMEs are traditionally associated with pollen tube elongation, this study provides strong evidence that PME48 impacts the mechanical properties of the intine wall during maturation of the pollen grain, which, in turn, influences pollen grain germination.
Steered migration in hard rock environments
Authors: Tertyshnikov Konstantin , Pevzner Roman , Bóna Andrej , Alonaizi Faisal , Gurevich Boris
Published: December 2014

Hard rock seismic exploration normally has to deal with rather complex geological environments. These types of environments are usually characterized by a large number of local heterogeneity (e.g., faults, fracture zones, and steeply dipping interfaces). The seismic data from such environments often have a poor signal‐to‐noise ratio because of the complexity of hard rock geology. To be able to obtain reliable images of subsurface structures in such geological conditions, processing algorithms that are capable of handling seismic data with a low signal‐to‐noise ratio are required for a reflection seismic exploration. In this paper, we describe a modification of the 3D Kirchhoff post‐stack migration algorithm that utilizes coherency attributes obtained by the diffraction imaging algorithm in 3D to steer the main Kirchhoff summation. The application to a 3D synthetic model shows the stability of the presented steered migration to the presence of high level of the random noise. A test on the 3D seismic volume, acquired on a mine site located in Western Australia, reveals the capability of the approach to image steep and sharp objects such as fracture and fault zones and lateral heterogeneity.
Novel interactions between non‐native mammals and fungi facilitate establishment of invasive pines
Authors: Wood Jamie R. , Dickie Ian A. , Moeller Holly V. , Peltzer Duane A. , Bonner Karen I. , Rattray Gaye , Wilmshurst Janet M.
Published: December 2014

The role of novel ecological interactions between mammals, fungi and plants in invaded ecosystems remains unresolved, but may play a key role in the widespread successful invasion of pines and their ectomycorrhizal fungal associates, even where mammal faunas originate from different continents to trees and fungi as in New Zealand.

We examine the role of novel mammal associations in dispersal of ectomycorrhizal fungal inoculum of North American pines (Pinus contorta, Pseudotsuga menziesii), and native beech trees (Lophozonia menziesii) using faecal analyses, video monitoring and a bioassay experiment.

Both European red deer (Cervus elaphus) and Australian brushtail possum (Trichosurus vulpecula) pellets contained spores and DNA from a range of native and non‐native ectomycorrhizal fungi.

Faecal pellets from both animals resulted in ectomycorrhizal infection of pine seedlings with fungal genera Rhizopogon and Suillus, but not with native fungi or the invasive fungus Amanita muscaria, despite video and DNA evidence of consumption of these fungi.

Native L. menziesii seedlings never developed any ectomycorrhizal infection from faecal pellet inoculation.

Synthesis. Our results show that introduced mammals from Australia and Europe facilitate the co‐invasion of invasive North American trees and Northern Hemisphere fungi in New Zealand, while we find no evidence that introduced mammals benefit native trees or fungi. This novel tripartite ‘invasional meltdown’, comprising taxa from three kingdoms and three continents, highlights unforeseen consequences of global biotic homogenization.
Harmful or Benign? Transnational Medical Networks and the Celibacy of Priests
Authors: Verhoeven Timothy
Published: December 2014

This article investigates the nineteenth‐century debate within transnational medical networks about the physiological effects of celibacy for priests. Many doctors, motivated in part by their animosity towards the Catholic Church, argued that the vow of celibacy was not only futile, but responsible for sexual immorality in the church. However, medical opinion was never uniform, and other doctors rallied to the church, defending the celibate vow as largely benign. Both sides shared a willingness to look abroad for support and inspiration. This article investigates this debate as a transnational phenomenon, as key texts were translated and published across Europe and North America, and as several notorious case‐studies emerged to form the focus of international controversy.
European Connections, Obstacles, and the Search for a New Concept of Religion: The Freethought Movement as an Example of Transnational Anti‐Catholicism in the Second Half of the Nineteenth Century
Authors: Dittrich Lisa
Published: December 2014

Freethinkers ranked among the main critics of Catholicism in the second half of the nineteenth century. Whereas the various Western European freethought movements have been relatively well studied on a national level, their cross‐border relationships remain substantially unexplored. A study of these connections can shed new light on transnational anti‐Catholicism in general and moreover help us to conceptualise this phenomenon in a European perspective. In this article, I will use the example of freethinkers in order to illustrate the difficult process of establishing transnational anti‐Catholic networks. The article begins with an outline of the various forms of connections of European anti‐Catholicism, concentrating in the following section on the first major international conference of freethinkers, the so‐called anti‐Council, which took place as a protest against the first Vatican Council (1869–1870). Attention is brought to the international dimensions of the meeting and to the reasons behind its rapid failure. In the third section, transnational anti‐Catholicism is studied in general in France, Spain, and Germany. I will focus especially on one constraint to cross‐border relationships. This will allow me to show that anti‐Catholicism was not only a secular endeavour, but was also inseparable from the widespread search for a religion more suited to a society undergoing rapid changes. This understanding of anti‐Catholicism offers a way of overcoming the still deep gap in historiography between the bi‐confessional countries and the Latin mainly mono‐confessional countries.
Current performance of food safety management systems of dairy processing companies in Tanzania
Authors: Kussaga Jamal B , Luning Pieternel A , Tiisekwa Bendantunguka P M , Jacxsens Liesbeth
Published: December 2014

A food safety management system (FSMS)‐diagnostic instrument was applied in 22 dairy processing companies to analyse the set‐up and operation of core control and assurance activities in view of the risk characteristics of the systems' context. Three clusters of companies were identified differing in levels of set‐up and operation of this FSMS and system outputs, but all operated in a similar moderate‐risk context. Microbiological assessment of products, environmental and hand samples indicated a poor to moderate food safety level. A two stage intervention approach has been proposed to enable commitment and sustainable improvement for the longer term.
Hepatic arterial infusion chemotherapy with cisplatin and sorafenib in hepatocellular carcinoma patients unresponsive to transarterial chemoembolization: A propensity score‐based weighting
Authors: Kondo Masaaki , Morimoto Manabu , Ishii Tomohiro , Nozaki Akito , Fukuda Hiroyuki , Numata Kazushi , Kobayashi Satoshi , Ohkawa Shinichi , Hidaka Hisashi , Nakazawa Takahide , Shibuya Akitaka , Okuse Chiaki , Suzuki Michihiro , Sakamaki Kentaro , Morita Satoshi , Maeda Shin , Tanaka Katsuaki
Published: December 2014

Objective

We aimed to evaluate the efficacy and tolerability of hepatic arterial infusion chemotherapy (HAIC) using cisplatin as an alternative to sorafenib for the treatment of hepatocellular carcinoma (HCC) patients who had not responded to transarterial chemoembolization (TACE).

Methods

Medical records of 127 consecutive HCC patients without extrahepatic metastasis (cisplatin, n = 44; sorafenib, n = 83) who had not responded to prior TACE at four institutions were retrospectively reviewed. An inverse probability of treatment weighting using propensity scoring was used to adjust for the selection bias.

Results

Severe adverse events accounting for treatment discontinuation occurred in 2.3% of the patients in the cisplatin group and 32.5% of those in the sorafenib group. The median overall survival (OS) period was 11.2 months (95% CI 4.8–17.7) in the cisplatin group and 10.2 months (95% CI 8.8–11.5) in the sorafenib group, respectively. After an inverse probability of treatment weighting adjustment, the survival outcome of the HAIC treatment group was not inferior to that of the sorafenib treatment group (hazard ratio 0.758; 95% CI 0.471–1.219, P = 0.253).

Conclusion

HAIC with cisplatin can be an alternative treatment for the selection of HCC patients who have not responded to prior TACE and cannot tolerate sorafenib.
The influence of childhood traffic‐related air pollution exposure on asthma, allergy and sensitization: a systematic review and a meta‐analysis of birth cohort studies
Authors: Bowatte G. , Lodge C. , Lowe A. J. , Erbas B. , Perret J. , Abramson M. J. , Matheson M. , Dharmage S. C.
Published: December 2014

The impact of early childhood traffic‐related air pollution (TRAP) exposure on development of asthma and allergies remains unclear. Birth cohort studies are the best available study design to answer this question, but the evidence from such studies has not been synthesized to date. We conducted a systematic review and meta‐analyses of published birth cohort studies to understand the association between early childhood TRAP exposure, and subsequent asthma, allergies and sensitization. Increased longitudinal childhood exposure to PM2.5 and black carbon was associated with increasing risk of subsequent asthma in childhood (PM2.5: OR 1.14, 95%CI 1.00 to 1.30 per 2 μg/m3 and black carbon: OR 1.20, 95%CI 1.05 to 1.38 per 1 × 10−5 m−1). Also, early childhood exposure to TRAP was associated with development of asthma across childhood up to 12 years of age. The magnitude of these associations increased with age, and the pattern was prominent for PM2.5. Increasing exposure to PM2.5 was associated with sensitization to both aero‐ and food allergens. There was some evidence that TRAP was associated with eczema and hay fever. In summary, exposure to TRAP was related to asthma and allergic diseases. However, the substantial variability across studies warrants long‐term birth cohort studies with regular repeated follow‐ups to confirm these findings.
Total serum IgE level influences oral food challenge tests for IgE‐mediated food allergies
Authors: Horimukai K. , Hayashi K. , Tsumura Y. , Nomura I. , Narita M. , Ohya Y. , Saito H. , Matsumoto K.
Published: December 2014

Probability curves predicting oral food challenge test (OFC) results based on specific IgE levels are widely used to prevent serious allergic reactions. Although several confounding factors are known to affect probability curves, the main factors that affect OFC outcomes are currently unclear. We hypothesized that an increased total IgE level would reduce allergic reactivity. Medical records of 337 and 266 patients who underwent OFCs for 3.5 g boiled hen's egg white and 3.1 ml raw cow's milk, respectively, were examined retrospectively. We subdivided the patients into three groups based on total IgE levels and age by percentile (<25th, 25–75th, and >75th percentiles), and logistic regression analyses were performed on each group. Patients with higher total IgE levels were significantly less responsive. In addition, age did not significantly affect the OFC results. Therefore, total IgE levels should be taken into account when predicting OFC results based on food‐specific IgE levels.
Altered faecal and mucosal microbial composition in post‐infectious irritable bowel syndrome patients correlates with mucosal lymphocyte phenotypes and psychological distress
Authors: Sundin J. , Rangel I. , Fuentes S. , Heikamp‐de Jong I. , Hultgren‐Hörnquist E. , de Vos W. M. , Brummer R. J.
Published: December 2014

Background

A subset of irritable bowel syndrome (IBS) patients, denoted post‐infectious IBS (PI‐IBS), develop symptoms after an enteric infection. Bacterial dysbiosis and mucosal inflammation have been proposed to be involved in the pathophysiology of this entity.

Aim

To characterise the mucosal and faecal microbiota in PI‐IBS, general IBS and healthy controls, and to investigate associations between the microbiota and the mucosal immune system.

Methods

Mucosal biopsies and faeces were collected from 13 PI‐IBS patients, 19 general IBS patients and 16 healthy controls. Global bacterial composition was determined by generating 16S rRNA amplicons that were examined by phylogenetic microarray hybridisation, principal component and redundancy analysis. We correlated previously reported lymphocyte proportions with the microbiota.

Results

Faecal microbiota composition of PI‐IBS patients differed significantly from both general IBS patients and healthy controls (P < 0.02). Both mucosal (P < 0.01) and faecal (P = 0.05) microbial diversity were reduced in PI‐IBS compared to healthy controls.

In the intraepithelial lymphocytes the previously published proportion of CD8+ CD45RA+ was negatively correlated with mucosal microbial diversity (P < 0.005). The previously published number of lamina propria lymphocytes was negatively correlated with mucosal microbial diversity (P < 0.05). Faecal microbial diversity was significantly negatively correlated with the Hospital Anxiety and Depression scale (P < 0.05).

Conclusions

We present data that distinguishes the intestinal microbiota of PI‐IBS patients from that of both general IBS patients and HC. The microbial composition is significantly associated with the HADs score and alterations in lymphocyte subsets proportions.
Me and my cellphone: constructing change from the inside through cellphilms and participatory video in a rural community
Authors: Mitchell Claudia , de Lange Naydene , Moletsane Relebohile
Published: December 2014

Drawing on fieldwork with rural teachers inSouthAfrica, this article highlights the significance of cellphone technology in participatory video and its potential to alter the research environment. To date much of the work in the area of participatory visual methodologies (including participatory video) and particularly in the context of working with marginalized communities, has relied on researcher‐led projects wherein it is the research team who as outsiders bring cameras for research with the community. In most cases the team departs, taking the cameras with them, but even in cases where the video cameras are left behind, sustainability is still an issue. In the case of cellphones and the production of cellphilms, the dynamics change. We reflect on our fieldwork in two rural schools, where all of the teachers had cellphones and regularly used them for various forms of communication including texting and accessingFacebook. None however, prior to the project had ever produced cellphilms, and only one had used a cellphone in any pedagogical way. In considering critical issues of using participatory video, we addressTouraine andDuff's (1981The voice and the eye: an analysis of social movements CambridgeUniversityPress,Cambridge) notion of the sociological intervention, and ask questions such as: Can this work with cellphones be regarded as a non‐interventionist intervention? How does the widespread use of cellphone technology alter the power dynamics related to ownership of both the production and the recording device? To what extent do some of the ethical concerns of previous work become obsolete and to what extent are there new ethical concerns (for example, distribution) to be addressed?
Kinder cuts and passionate modesties: the complex ecology of the invitation in participatory research
Authors: Franks Aaron
Published: December 2014

This paper draws on a series of applied theatre and popular education workshops in Glasgow, Scotland in 2010–11. While the workshop content involved participatory applied theatre and popular education as tools for community environmental and social justice organising, the performance‐based methods of these workshops also troubled assumptions of the participating subject as singular and self‐reflexive. In the paper I propose that the question of subjectivity in participatory research might be fruitfully linked to the ‘content’ of environmental and social justice in two ways. First, applied theatre is presented as a distinctively mediated participatory space that can rely on an unrealisable conception of subjectivity. I argue that exploring the tensions within this mediated space can illuminate such tensions in participatory research generally, and further a ‘passionate modesty’ – a shared reckoning of limitations that can enrich the potential for praxis of participatory research. ‘Passionate modesty’ is brought to bear on activist research, asking us not to bypass in our writing the complexities and costs of participating in relations of solidarity and resistance. This participatory space is further explored as one of important ecological consequence for the co‐production of knowledge. Barad and Bell's work on making the ‘cuts’ that determine what we include (and exclude) in our attentions is used to argue that participatory research, and creative methods in particular, can orient our attention to social–nature relations in distinct and powerful ways. An ecological perspective is proposed, where acknowledging the asymmetry of encounter and the co‐performance of responsibility might ‘cut’ such research more modestly but perhaps more generatively. In a concluding response to this invitation, I return to the content of the Glasgow workshops on environmental and social justice, and the complex relationship between the politics of grappling with injustices and a participatory politics of co‐learning.