bluuebunny/crossref_metadata_2025 huggingface dataset:
Parametric energy conversion of thermoacoustic vibrations
Authors: Guthy C. , Van Neste C. W. , Mitra S. , Bhattacharjee S. , Thundat T.
Published: May 2012

We demonstrate a parametric energy conversion method of thermoacoustic (TA) vibrations into electrical oscillations of a LC circuit. The inductance modulation necessary to excite the parametric oscillations is achieved by varying the air gap between two halves of a ferrite E-core coil. As a proof-of-concept, the parametric converter was attached to a Sondhauss tube that converts the heat into acoustic vibrations. The maximum total acoustic power output of this thermoacoustic engine was ∼5.3 mW. A flexible metallic membrane capping the Sondhauss tube connected to the moving half E-core served as a mechanical oscillator. The resonance frequency of the membrane was matched with the operating frequency (130 Hz) of the Sondhauss tube for resonant energy extraction. We have characterized the power output of the complete system as a function of electrical load. The maximum electrical power of 2.3 mW produced by the system corresponds to an acoustic-to-electric conversion efficiency of 44%.
Controlled faceting in 〈110〉 germanium nanowire growth by switching between vapor-liquid-solid and vapor-solid-solid growth
Authors: Kolíbal Miroslav , Kalousek Radek , Vystavěl Tomáš , Novák Libor , Šikola Tomáš
Published: May 2012

We show that the hexagonal cross-section of germanium nanowires grown in the 〈110〉 direction by physical vapor deposition is a consequence of minimization of surface energy of the collector droplet. If the droplet is lost or solidified, two {001} sidewall facets are quickly overgrown and the nanowire exhibits a rhomboidal cross-section. This process can be controlled by switching between the liquid and solid state of the droplet, enabling the growth of nanowires with segments having different cross-sections. These experiments are supported by in-situ microscopic observations and theoretical model.
Manipulation of a single electron spin in a quantum dot without magnetic field
Authors: Bednarek S. , Pawłowski J. , Skubis A.
Published: May 2012

In this paper, we propose the construction of a nanodevice performing the spin rotations of an electron confined in an electrostatic quantum dot without the use of a magnetic field. Sinusoidally varying voltage applied in different phases to four gates causes the electron to move along a two-dimensional closed path. The spin-orbit interaction that is present in the structure induces spin rotations. For a properly adjusted AC signal duration, the logical NOT operation or the Hadamard quantum gate can be performed on the electron spin. We perform a simulation of the nanodevice’s time evolution.
Reevaluation of the beneficial effect of Cu(In,Ga)Se2 grain boundaries using Kelvin probe force microscopy
Authors: Zhang Zhenhao , Tang Xiaochen , Kiowski Oliver , Hetterich Michael , Lemmer Uli , Powalla Michael , Hölscher Hendrik
Published: May 2012

Potential variations at grain boundaries are analyzed on the surface and on untreated cross sections of the absorber in a Cu(In,Ga)Se2 solar cell applying Kelvin probe force microscopy. We observe three different types of potential variations between grain boundaries (dip-, step-, or peak-shape). The potential variations on cross sections are smaller than that on surfaces. Since the properties of grain boundaries on cross sections can be expected to resemble more closely the ones buried in the bulk as those on absorber surfaces, it is important to interpret functionalities of grain boundaries based on observations on cross sections.
Variation of the intersublattice exchange coupling due to hydrogen absorption in Er2Fe14B: A high-field magnetization study
Authors: Tereshina E. A. , Tereshina I. S. , Kuz’min M. D. , Skourski Y. , Doerr M. , Chistyakov O. D. , Telegina I. V. , Drulis H.
Published: May 2012

Single crystals of a series of hydrides Er2Fe14BHx (x ≤ 2.5) have been produced and studied in pulsed magnetic fields up to 60 T. The magnetization curve of Er2Fe14B in the easy direction [100] features a stepwise anomaly at about 45 T, corresponding to the first-order phase transition. A similar magnetization jump is also present in the curve along [110], but at a higher field, ∼52 T. The [100] data of the parent and hydrogen-charged Er2Fe14BHx with x = 0.25, 1.5, 2.5 were used to deduce the Er-Fe molecular field Hmol as a function of hydrogen content x. After moderate initial decrease, Hmol(x) drops abruptly above x = 1.5. Hydrogenation results in a 12% reduction of the Er-Fe molecular field in Er2Fe14BH2.5 as compared to Er2Fe14B. For reference, influence of hydrogen on Hmol in an Er2Fe17-H system is also presented.
Frequency-selective contrast on variably doped p-type silicon with a scanning microwave microscope
Authors: Imtiaz A. , Wallis T. M. , Lim S.-H. , Tanbakuchi H. , Huber H.-P. , Hornung A. , Hinterdorfer P. , Smoliner J. , Kienberger F. , Kabos P.
Published: May 2012

We report on frequency-dependent contrast in d(S11)/dV measurements of a variably doped p-type silicon sample in the frequency range from 2 GHz to 18 GHz. The measurements were conducted with a scanning microwave microscope. The measurements were done at selected frequencies while varying the DC tip voltage. The measured d(S11)/dV signal shows a maximum for doping concentrations (NA) of 1015 cm−3−1016 cm−3 at 2.3 GHz. As the microscope operating frequency is increased, this maximum sequentially “switches” through the regions of increasing dopant concentration, displaying a maximum for NA of 1017 cm−3−1018 cm−3 at 17.9 GHz. The frequency dependent “switching” is attributed to the physics of tip-to-sample interaction, particularly as related to the frequency-dependent local surface resistance and the depletion capacitance that control the RC time constant of tip-to-sample interaction. This provides a unique platform for local, frequency-selective, spatially resolved microwave spectroscopy of semiconducting materials.
First-principle description for the high-harmonic generation in a diamond by intense short laser pulse
Authors: Otobe T.
Published: May 2012

We present a first-principles description for the electron excitation and the high-harmonic generation (HHG) in a diamond by intense laser pulse irradiation and their laser parameter dependence. Above band gap harmonics are generated after the peak of the incident laser pulse and have duration much shorter than the laser pulse. The intensity of individual harmonic peaks increases as laser intensity increases nonlinearly, and we find the blue shift of the HHG spectrum when the optical breakdown occurs.
Near threshold all-optical backaction amplifier
Authors: McRae Terry G. , Bowen Warwick P.
Published: May 2012

A near threshold all-optical backaction amplifier is realized. Operating near threshold in an integrated micron scale architecture allows a nearly three orders of magnitude improvement in both gain and optical power requirements over the only previous all-optical implementation, with 37 dB of gain achieved for only 12 μW of input power. Minor parameter adjustment allows narrowband optical filtering.
A versatile and reconfigurable setup for all-terahertz time-resolved pump-probe spectroscopy
Authors: Elezzabi A. Y. , Maraghechi P.
Published: May 2012

A versatile optical setup for all-terahertz (THz) time resolved pump-probe spectroscopy was designed and tested. By utilizing a dual THz pulse generator emitter module, independent and synchronized THz radiation pump and probe pulses were produced, thus eliminating the need for THz beam splitters and the limitations associated with their implementation. The current THz setup allows for precise control of the electric fields splitting ratio between the THz radiation pump and probe pulses, as well as in-phase, out-of-phase, and polarization dependent pump-probe spectroscopy. Since the present THz pump-probe setup does not require specialized THz radiation optical components, such as phase shifters, polarization rotators, or wide bandwidth beam splitters, it can be easily implemented with minimal alterations to a conventional THz time domain spectroscopy system. The present setup is valuable for studying the time dynamics of THz coherent phenomena in solid-state, chemical, and biological systems.
Domain tuning in mixed-phase BiFeO3 thin films using vicinal substrates
Authors: You Lu , Yasui Shintaro , Ehara Yoshitaka , Zou Xi , Ding Hui , Chen Zuhuang , Chen Weigang , Chen Lang , Funakubo Hiroshi , Wang Junling
Published: May 2012

The structural and ferroelectric domain variants of highly strained BiFeO3 films grown on vicinal LaSrAlO4 substrates were studied by piezoelectric force microscopy and high-resolution x-ray reciprocal space mapping. Through symmetry breaking of the substrate surface, ferroelastic domain variants in the highly strained MC phase BiFeO3 can be greatly reduced in thinner, purely tetragonal-like films. More interestingly, in thicker, mixed phase films, the structural variants can also be tailored by substrate vicinality. These findings lead to better understanding of the phase evolution and polarization rotation process in the strain-driven polymorphic phase system.
Ring-shaped NdFeB-based magnetic tweezers enables oscillatory microrheology measurements
Authors: Lin Jun , Valentine Megan T.
Published: May 2012

We present the design and characterization of a magnetic tweezers device that employs a ring-shaped neodymium iron boron (NdFeB) magnet. Because the gradient of the magnetic field generated by ring magnets changes sign along its symmetry axis, magnetic tweezers devices that employ ring magnets can both push and pull on microscale magnetic beads, opening new avenues for the micromanipulation of soft materials. We demonstrate the application of such a device to oscillatory microrheology measurements of soft networks of microtubules, an essential cellular biopolymer.
Direct evidence of n-type doping in organic light-emitting devices: N free Cs doping from CsN3
Authors: Lee Jeihyun , Lee Hyunbok , Jeon Pyungeun , Jeong Kwangho , Gun Kim Tae , Won Kim Jeong , Yi Yeonjin
Published: May 2012

Cesium azide (CsN3) is confirmed to be decomposed during thermal evaporation. Only Cs could be deposited on tris(8-hydroxyquinolinato)aluminum (Alq3) and n-type doping is easily achieved. Organic light-emitting devices with CsN3 show highly improved current density-luminance-voltage characteristics compared to the control device without CsN3. To understand the origin of the improvements, in situ x-ray and UV photoemission spectroscopy measurements were carried out and a remarkable reduction in electron injection barrier is verified with successive deposition of Al on CsN3 on Alq3. CsN3 has a potential as alternative to doping the electron transport layer by replacing the direct deposition of alkali metals.
Internal dynamics of Newtonian and viscoplastic fluid avalanches down a sloping bed
Authors: Andreini Nicolas , Epely-Chauvin Gaël , Ancey Christophe
Published: May 2012

We experimentally investigated the spreading of fluid avalanches (i.e., fixed volumes of fluid) down an inclined flume. Emphasis was given to the velocity field within the head. Using specific imaging techniques, we were able to measure velocity profiles within the flowing fluid far from the sidewalls. We studied the behavior of Newtonian and viscoplastic fluids for various flume inclinations and initial masses. For the Newtonian fluids tested (glycerol and Triton X100), we compared the measured velocity field with that predicted by lubrication theory. Provided that the flow Reynolds number Re was sufficiently low (typically Re < 1), there was excellent agreement between theory and experiment except for the very thin region just behind the contact line. For higher Reynolds numbers (typically Re ∼ 10), the discrepancy between theory and experiment was more marked (relative errors up to 17% for the body). As viscoplastic materials, we used Carbopol ultrez 10. For the body, agreement between theoretical and measured velocity profiles was fairly satisfactory whereas it was very poor for the tip region as the curvature of the free surface became more pronounced: the velocities were not only much lower than those predicted by lubrication theory, but there was also evidence of slipping in the flow part adjacent to the contact line.
Migration mechanism for atomic hydrogen in porous carbon materials
Authors: Narayanan Badri , Zhao Yufeng , Ciobanu Cristian V.
Published: May 2012

To explain the fast kinetics of H in porous carbon, we propose that the migration relies on H hopping from a carbon nanotube (CNT) to another. Using density functional theory, we have found that the barrier for H hopping becomes smaller than that for diffusion along a tube for certain CNT separations, decreasing to less than 0.5 eV for separations of ∼3.1 Å. Such significant reduction occurs irrespective of radius, chirality, registry, and orientation of the two CNTs: the diffusion is thus facilitated by the porous nature of the material itself. The mechanism proposed is applicable for any porous carbon-based nanomaterials.
Experimental study of light output power for vertical GaN-based light-emitting diodes with various textured surface and thickness of GaN layer
Authors: Kwack Ho-Sang , Lim Hyun Soo , Song Hyun-Don , Jung Sung-Hoon , Cho Hyun Kyong , Kwon Ho-Ki , Oh Myeong Seok
Published: May 2012

The light output power (LOP) of vertical-type GaN-based light emitting diodes (LED) with surface roughness (texture) can be changed by texture size, density, and thickness of GaN film or by the combined effects of texture formation and thickness of GaN film. We have investigated these changes experimentally and note that the enhancement of the LOP by a factor of 2.4 can be improved with optimum texturing parameters as compared to that without texturing. In addition, the LOP of GaN-based LEDs under the same texture density increase slightly as thickness of GaN film decreases. Base on these results, we have evidently demonstrated that the enhancement factors of LOP are related to the correlation between texture size (density) and thickness of GaN film.
Towards a cognitive pragmatics of collective remembering
Authors: Bietti Lucas M.
Published: May 2012

This article aims to provide a cognitive and discourse based theory to collective memory research. Despite the fact that a large proportion of studies in collective memory research in social, cognitive, and discourse psychology are based on investigations of (interactional) cognitive and discourse processes, neither linguistics nor cognitive and social psychologists have proposed an integrative, interdisciplinary and discursive-based theory to memory research. I argue that processes of remembering are always embodied and action oriented reconstructions of the past, which are highly dynamic and malleable by means of communication and context. This new approach aims to provide the grounds for a new ecologically valid theory on memory studies which accounts for the mutual interdependencies between communication, cognition, meaning, and interaction, as guiding collective remembering processes in the real-world activities.
On local bars and imported beer
Authors: Vallée Richard
Published: May 2012

“Imported” is a member of a large family of adjectives, including “enemy”, “domestic”, “local”, “exported”, “foreign”. Call these terms contextuals. Contextuals are prima facie context-sensitive expressions in that the same contextual sentence can have different truth-values, and hence different truth-conditions, from utterance to utterance. I use Perry’s multipropositionalist framework to get a new angle on contextuals. I explore the idea that the lexical linguistic meaning of contextual adjectives introduces two conditions to the cognitive significance of an utterance. These conditions contain a variable, y, that does not correspond to any lexical component in the sentence. This is the available tool for letting the speakers’ intentions, or what the speakers have in mind, play a semantic role. My view focuses on the complex condition that linguistic meaning (as type) sometimes semantically determines.
Speech acts, attitudes, and scientific practice
Authors: McKaughan Daniel J.
Published: May 2012

There are certain illocutionary acts (such as hypothesizing, conjecturing, speculating, guessing, and the like) that, contrary to John Searle’s (1969, 1975, 1979) speech act theory, cannot be correctly classified as assertives. Searle’s sincerity and essential conditions on assertives require, plausibly, that we believe our assertions and that we are committed to their truth. Yet it is a commonly accepted scientific practice to propose and investigate an hypothesis without believing it or being at all committed to its truth. Searle’s attempt to accommodate such conjectural acts by claiming that the degree of belief and of commitment expressed by some assertives “may approach or even reach zero” (1979: 13) is unsuccessful, since it evacuates his thesis that these are substantive necessary conditions on assertives of any force. The illocutionary acts in question are central to scientific activity and so cannot be plausibly ignored by a theory of speech acts. The problem is not limited simply to Searle’s theory, since even theories which depart markedly from Searle’s in other respects are often committed to similar characterizations of assertion.
Evaluative meaning
Authors: Finkbeiner Rita
Published: May 2012

Linguistic evaluation has become an important area of inquiry in recent years. In the traditions of, e.g., lexical semantics, phraseology, corpus linguistics, and interactional linguistics, a large inventory of linguistic means have been identified by which speakers can express evaluative meanings. However, the class of German sentential idioms, e.g., Das kannst du dir in die Haare schmieren (lit. ‘You can smear that into your hair’, fig. ‘That is useless’), has not gained much attention. This paper explores how the evaluative meaning of German sentential idioms is constructed syntactically, semantically, and pragmatically. In particular, it is investigated how the meaning of these idioms interacts with the context in which they are used. A context model of evaluation is developed in which the cognitive category of cause plays a central role. The model is applied to contextualized examples, the findings supporting the hypothesis that cause is one of the core categories of evaluation.
Linguistic synaesthesia, perceptual synaesthesia, and the interaction between multiple sensory modalities
Authors: Ronga Irene , Bazzanella Carla , Rossi Ferdinando , Iannetti Giandomenico
Published: May 2012

Recent studies on cortical processing of sensory information highlight the importance of multisensory integration, and define precise rules governing reciprocal influences between inputs of different sensory modalities. We propose that psychophysical interactions between different types of sensory stimuli and linguistic synaesthesia share common origins and mechanisms. To test this hypothesis, we compare neurophysiological findings with corpus-based analyses relating to linguistic synaesthesia. Namely, we present Williams’ hypothesis and its recent developments about the hierarchy of synaesthetic pairings, and examine critical aspects of this theory concerning universality, directionality, sensory categories, and usage of corpora. These theoretical issues are verified against linguistic data derived from corpus-based analyses of Italian synaesthetic pairings related to auditory and tactile modalities. Our findings reveal a strong parallel between linguistic synaesthesia and neurophysiological interactions between different sensory stimuli, suggesting that linguistic synaesthesia is affected by tendencies similar to the rules underlying the perceptual association of distinct sensory modalities.
The cognitive representation of nature in language
Authors: Romero-Trillo Jesús , Espigares Tíscar
Published: May 2012

The present article proposes a taxonomy of features to describe the grammar of natural landscapes with the parameters that can account for the preferences of speakers in the description of nature. The taxonomy is the theoretical foundation designed for the Corpus of Language and Nature (CLAN Corpus),1 compiled worldwide, whose aim is to describe the cognitive and emotional preferences in the observation of nature by speakers of different languages. For this purpose, we have delineated the basic visual features deemed essential to read natural landscapes in order to create a network of cognitive variables in the perception of nature with its various components and features. These features of landscapes are complemented with a description of the cognitive variables that mould the individual’s perception of nature and the emotions enacted after its contemplation.
Firms’ linkages with universities and public research institutes in Argentina: factors driving the selection of different channels
Authors: Arza Valeria , Vazquez Claudia
Published: May 2012

Knowledge flows between public research organisations (PROs) and firms may occur through various channels. Channel selection may have different drivers and effects. Although much research has been carried out on the drivers of firms and researchers to connect with each other, less attention has been paid to the determinants of the selection of different channels of interaction. This research analysis factors driving firms’ selection of different channels of interactions with public research organisations (PROs), both public research institutes (PRIs) and universities (UNIs). The paper estimates bi-variate probit models with sample selection using micro data for 2007 from a representative survey of Argentinean firms. The classification of channels is based on previous research for Latin America and includes four types according to the main goals that firms and public research organisations seek when interacting: traditional, service, commercial and bi-directional channels. We find that factors driving the selection of the bi-directional channel are different from those driving selection of the others. In particular, firms choosing this channel employ a more skilled workforce and generally interact with PRIs and UNIs in order to benefit their own innovative activities. Thus, this commitment to knowledge capabilities and innovation when firms use the bi-directional channel may enhance the potential of PRO–firm interactions to upgrade the national innovation system (NIS).
Is the Italian Government effective in relaxing the financial constraints of high technology firms?
Authors: Colombo Massimo
                      G. , Croce Annalisa , Guerini Massimiliano
Published: May 2012

The present work analyses the effect of public finance on firm investments in a longitudinal sample of 293 Italian unlisted owner-managed, new technology-based firms (NTBFs), observed over a 10-year period from 1994 to 2003. We find that large, old NTBFs and those located in the north of Italy are not financially constrained, while small, young NTBFs and those located in the south of Italy rely significantly on internal capital to finance their investments. Public finance may play a prominent role for these latter firms. Indeed, empirical evidence shows that receipt of public subsidies by financially constrained NTBFs results in a reduction of investment–cash flow sensitivity in the long run. We interpret these results as an indication of the relaxation of financial constraints. Moreover, we find that, after receiving public finance, young and small firms increase their investment rate while NTBFs located in the southern regions do not. Nonetheless, small and young NTBFs benefit greatly from public intervention, but are less likely to obtain public support than their larger and older peers. Italian policy measures have also paid particular attention to NTBFs located in the south of Italy, but we find that public finance has no effect on the investment rate for southern NTBFs. This evidence raises some doubts about the overall efficacy of Italian governmental intervention in this domain.
Tks5-dependent formation of circumferential podosomes/invadopodia mediates cell–cell fusion
Authors: Oikawa Tsukasa , Oyama Masaaki , Kozuka-Hata Hiroko , Uehara Shunsuke , Udagawa Nobuyuki , Saya Hideyuki , Matsuo Koichi
Published: May 2012

Osteoclasts fuse to form multinucleated cells during osteoclastogenesis. This process is mediated by dynamic rearrangement of the plasma membrane and cytoskeleton, and it requires numerous factors, many of which have been identified. The underlying mechanism remains obscure, however. In this paper, we show that Tks5, a master regulator of invadopodia in cancer cells, is crucial for osteoclast fusion downstream of phosphoinositide 3-kinase and Src. Expression of Tks5 was induced during osteoclastogenesis, and prevention of this induction impaired both the formation of circumferential podosomes and osteoclast fusion without affecting cell differentiation. Tyrosine phosphorylation of Tks5 was attenuated in Src−/− osteoclasts, likely accounting for defects in podosome organization and multinucleation in these cells. Circumferential invadopodia formation in B16F0 melanoma cells was also accompanied by Tks5 phosphorylation. Co-culture of B16F0 cells with osteoclasts in an inflammatory milieu promoted the formation of melanoma–osteoclast hybrid cells. Our results thus reveal an unexpected link between circumferential podosome/invadopodium formation and cell–cell fusion in and beyond osteoclasts.
Spectraplakins: Master orchestrators of cytoskeletal dynamics
Authors: Suozzi Kathleen C. , Wu Xiaoyang , Fuchs Elaine
Published: May 2012

The dynamics of different cytoskeletal networks are coordinated to bring about many fundamental cellular processes, from neuronal pathfinding to cell division. Increasing evidence points to the importance of spectraplakins in integrating cytoskeletal networks. Spectraplakins are evolutionarily conserved giant cytoskeletal cross-linkers, which belong to the spectrin superfamily. Their genes consist of multiple promoters and many exons, yielding a vast array of differential splice forms with distinct functions. Spectraplakins are also unique in their ability to associate with all three elements of the cytoskeleton: F-actin, microtubules, and intermediate filaments. Recent studies have begun to unveil their role in a wide range of processes, from cell migration to tissue integrity.
First Report of Ascochyta rabiei Causing Ascochyta Blight of Chickpea in Argentina
Authors: Viotti G. , Carmona M. A. , Scandiani M. , Formento A. N. , Luque A.
Published: May 2012

In November 2011, lesions similar to those reported for Ascochyta blight (1) were observed on Cicer arietinum L. (chickpea) plants growing in three commercial fields located at Río Primero and Río Segundo (Cordoba Province) and Lobería (Buenos Aires Province), Argentina. Disease incidence (percentage of plants affected) was 100% in all fields surveyed. Plants showed leaves, petioles, stems, and pods with brown lesions. Symptoms on leaves and pods were circular to oval (2 to 14 mm) while in the stems the lesions were elongated (2 to 30 mm). Seeds appeared small and shriveled with brown discoloration. Morphology of the fungi was examined on infected tissues. Numerous black pycnidia measuring 94.6 to 217.9 μm (145.9 ± 28.8 μm), arranged in concentric rings, were observed within of all the lesions. Conidia were predominantly aseptate, straight, hyaline with blunt ends, and measured 9.3 to 12.9 (11.3 ± 1.12) × 3.3 to 5.0 μm (4.2 ± 0.51). Morphological characteristics of the pathogen were similar to those described for Ascochyta rabiei (Pass.) Labrousse (teleomorph Didymella rabiei (Kovacheski) v. Arx (= Mycosphaerella rabiei Kovacheski)) (2). Fungus from infected leaf tissues was isolated on potato dextrose agar. Pathogenicity tests were conducted on seedlings of the susceptible cultivar by spraying leaves of each of 100 seedling plants with 10 ml of a conidial suspension (2 × 104 conidia/ml) of the isolated pathogen with a handheld atomizer. Plants were covered with plastic bags and placed in a growing chamber at 20 to 25°C for 3 days. The plastic bags were removed and the plants were maintained in high humidity at the same temperature. Noninoculated plants were used as controls. After 5 days, all inoculated plants showed typical symptoms. Foliar and stem lesions symptoms were similar to those originally observed in the field. Control plants remained healthy. Koch's postulates were fulfilled by isolating A. rabiei from inoculated plants. The colonies and the morphology of conidia were the same as those of the original isolates. To our knowledge, this is the first report of A. rabiei infecting chickpeas in Argentina. The outbreak of Ascochyta blight in Argentina is of concern because of its severity and the possibility that the pathogen was introduced on seed. This report underscores the need for further research on effective management programs for Ascochyta blight.

References: (1) B. Bayaa and W. Chen. Compendium of Chickpea and Lentil Diseases and Pests The American Phytopathological Society, St. Paul, MN, 2011. (2) E. Punithalingam and P. Holliday. Page 337 in: CMI Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1972.
Elytra boost lift, but reduce aerodynamic efficiency in flying beetles
Authors: Johansson L. Christoffer , Engel Sophia , Baird Emily , Dacke Marie , Muijres Florian T. , Hedenström Anders
Published: May 2012

Flying insects typically possess two pairs of wings. In beetles, the front pair has evolved into short, hardened structures, the elytra, which protect the second pair of wings and the abdomen. This allows beetles to exploit habitats that would otherwise cause damage to the wings and body. Many beetles fly with the elytra extended, suggesting that they influence aerodynamic performance, but little is known about their role in flight. Using quantitative measurements of the beetle's wake, we show that the presence of the elytra increases vertical force production by approximately 40 per cent, indicating that they contribute to weight support. The wing-elytra combination creates a complex wake compared with previously studied animal wakes. At mid-downstroke, multiple vortices are visible behind each wing. These include a wingtip and an elytron vortex with the same sense of rotation, a body vortex and an additional vortex of the opposite sense of rotation. This latter vortex reflects a negative interaction between the wing and the elytron, resulting in a single wing span efficiency of approximately 0.77 at mid downstroke. This is lower than that found in birds and bats, suggesting that the extra weight support of the elytra comes at the price of reduced efficiency.
A long-time limit for world subway networks
Authors: Roth Camille , Kang Soong Moon , Batty Michael , Barthelemy Marc
Published: May 2012

We study the temporal evolution of the structure of the world's largest subway networks in an exploratory manner. We show that, remarkably, all these networks converge to a shape that shares similar generic features despite their geographical and economic differences. This limiting shape is made of a core with branches radiating from it. For most of these networks, the average degree of a node (station) within the core has a value of order 2.5 and the proportion of
k
= 2 nodes in the core is larger than 60 per cent. The number of branches scales roughly as the square root of the number of stations, the current proportion of branches represents about half of the total number of stations, and the average diameter of branches is about twice the average radial extension of the core. Spatial measures such as the number of stations at a given distance to the barycentre display a first regime which grows as
r
2
followed by another regime with different exponents, and eventually saturates. These results—difficult to interpret in the framework of fractal geometry—confirm and yield a natural explanation in the geometric picture of this core and their branches: the first regime corresponds to a uniform core, while the second regime is controlled by the interstation spacing on branches. The apparent convergence towards a unique network shape in the temporal limit suggests the existence of dominant, universal mechanisms governing the evolution of these structures.
Effects of polymorphisms in the porcine microRNA MIR206/MIR133B cluster on muscle fiber and meat quality traits
Authors: Lee Jun‐Seong , Kim Jun‐Mo , Lim Kyu‐Sang , Hong Jae‐Sang , Hong Ki‐Chang , Lee Young Sik
Published: May 2012

MicroRNAs are a class of small non‐coding RNA molecules that repress gene expression primarily at the post‐transcriptional level. Genetic variations in microRNA genes may contribute to phenotypic differences by altering the expression of microRNAs and their targets. Here, we identified 12 single nucleotide polymorphisms (SNPs) in the genomic region of the porcine
MIR206
/
MIR133B
cluster, 10 and 2 of which were associated with
MIR206
and
MIR133B
respectively. All 12 SNPs were located within primary microRNAs. Allele frequency determination in different pig breeds (Berkshire, n = 153; Landrace, n = 125; Yorkshire, n = 173) and association studies of muscle fiber characteristics, lean meat production and meat quality traits were performed on the
MIR206
and
MIR133B SNPs. The
MIR206 SNPs were associated with the percentage of type IIa and IIb fibers for muscle fiber area composition, meat quality traits including drip loss and lightness, and backfat thickness, a parameter of lean meat production. In addition, we found significant association of the
MIR133B SNPs with total muscle fiber number, loin eye area, and muscle pH. Furthermore, these SNPs significantly affected the levels of mature
MIR206
and
MIR133B
, respectively, primarily by regulating the processing of primary microRNAs into precursor microRNAs. Interestingly, altered
MIR206
levels correlated with phenotypic variability among genotypes of the
MIR206 SNP. Our data suggest that polymorphisms in the porcine
MIR206
/
MIR133B
cluster are a genetic factor affecting muscle and meat quality traits.
Detection of copy number variants in the horse genome and examination of their association with recurrent laryngeal neuropathy
Authors: Dupuis M.C. , Zhang Z. , Durkin K. , Charlier C. , Lekeux P. , Georges M.
Published: May 2012

We used the data from a recently performed genome‐wide association study using the Illumina Equine SNP50 beadchip for the detection of copy number variants (CNVs) and examined their association with recurrent laryngeal neuropathy (RLN), an important equine upper airway disease compromising performance. A total of 2797 CNVs were detected for 477 horses, covering 229 kb and seven SNPs on average. Overlapping CNVs were merged to define 478 CNV regions (CNVRs). CNVRs, particularly deletions, were shown to be significantly depleted in genes. Fifty‐two of the 67 common CNVRs (frequency ≥ 1%) were validated by association mapping, Mendelian inheritance, and/or Mendelian inconsistencies. None of the 67 common CNVRs were significantly associated with RLN when accounting for multiple testing. However, a duplication on chromosome 10 was detected in 10 cases (representing three breeds) and two unphenotyped parents but in none of the controls. The duplication was embedded in an 8‐Mb haplotype shared across breeds.
Focused fluid flow systems of the Zhongjiannan Basin and Guangle Uplift, South China Sea
Authors: Sun Qiliang , Wu Shiguo , Cartwright Joseph , Lüdmann Thomas , Yao Genshun
Published: May 2012

In this article, we document a large number of focused fluid escape structures using high quality 2D seismic reflection data and multibeam bathymetry data from a poorly known area at the intersection of the northern South China Sea (SCS) and the western SCS. Three types of focused fluid escape systems are identified and described: mud volcanoes, pipes and associated pockmarks. The mud volcanoes occur singly or as clustered groups. The overpressure driving the mud volcanism is argued herein to be related to the generation of thermogenic hydrocarbons. The clustered distributions are related to localized tectonic uplift in the basin. Pipes mainly occur within the Guangle Uplift or accompany the mud volcano clusters. The pipes located within the Guangle Uplift are attributed to carbonate dissolution caused by hydrothermal fluids. Fluids ascended through these structures and were expelled at the palaeo‐seabed or present seabed forming palaeo‐pockmarks and present‐day pockmarks. Some ‘mega‐pockmarks’ show evidence of enlargement due to bottom currents. The marginal basins of the SCS are petroliferous, with attention gradually shifting to the deep‐water area. Our results show that fluid migration must be taken into account when assessing seabed stability. This analysis also improves our understanding the petroleum geology in the study area, and is also useful for predicating where chemosynthetic ecosystems may be located.
Component‐resolved diagnosis with commercially available D. pteronyssinus Der p 1, Der p 2 and Der p 10: relevant markers for house dust mite allergy
Authors: Bronnert M. , Mancini J. , Birnbaum J. , Agabriel C. , Liabeuf V. , Porri F. , Cleach I. , Fabre A. , Deneux I. , Grandné V. , Grob J.‐J. , Berbis P. , Charpin D. , Bongrand P. , Vitte J.
Published: May 2012

Background

Commercially available house dust mite components may improve routine testing of allergic patients.

Objective

To establish the prevalence and serum levels of IgE to commercial Der p 1, Der p 2, Der p 10 and the carbohydrate MUXF3 in house dust‐mite allergic patients. To compare individual vs. allergen microarray methods.

Methods

Prevalence and serum levels of IgE to Dermatophagoides pteronyssinus extract and components Der p 1, Der p 2, Der p 10 and MUXF3, specific IgG4 to D. pteronyssinus, total serum IgE levels, and clinical features (age, asthma, rhinitis and atopic dermatitis) were determined in 123 patients (64 children) with the ImmunoCAP® method. ImmunoCAP ISAC® was performed in 24 patients.

Results

All patients had serum IgE to D. pteronyssinus. Prevalences of serum IgE to commercial components were Der p 1 93%, Der p 2 77% (Der p 1 or Der p 2 94%), Der p 10 28% and MUXF3 25%. Levels of D. pteronyssinus IgE strongly correlated with Der p 1 and Der p 2 IgE (r = 0.89 and 0.85 respectively), but not Der p 10 and MUXF3. ImmunoCAP® and ImmunoCAP ISAC® were concordant, but the quantitative correlation was poor. No clinical implication for the prevalence, levels, or molecular IgE reactivity profile to house dust mite components was found.

Conclusions and Clinical Relevance

Commercially available Der p 1 and Der p 2 strongly correlate with IgE D. pteronyssinus. The lack of Der p 1 and Der p 2 IgE may help with differential diagnosis. Der p 10 serum IgE prevalence and levels suggest different patterns in food and mite‐related tropomyosin sensitization. Serum IgE to carbohydrate MUXF3, although unexpectedly prevalent, were low and did not modify D. pteronyssinus IgE levels. Follow‐up may be best carried out with individual rather than microarrayed components.
No metabolic impact of surgical normalization of hyperandrogenism in postmenopausal women with ovarian androgen‐secreting tumours
Authors: Pelusi Carla , Forlani Giulia , Zanotti Laura , Gambineri Alessandra , Pasquali Renato
Published: May 2012

Aim

To examine the impact of surgical normalization of testosterone on body weight and on glucose and lipid metabolism and insulin sensitivity in a group of hyperandrogenic women with ovarian androgen‐secreting tumours (OAST).

Methods

Five consecutive postmenopausal hyperandrogenic patients (aged 63 ± 5 years) with a diagnosis of OAST were prospectively evaluated. Clinical signs, symptoms and metabolic and hormonal parameters were collected at the time of the diagnosis and at follow‐up, 12 months after surgical oophorectomy. A group of 15 age‐matched and body mass index‐matched postmenopausal control women served as a reference group.

Results

At baseline, patients with OAST had very high testosterone levels and inappropriately low gonadotrophin levels for their menopausal status. All the women were overweight or obese, and one had a history of polycystic ovary syndrome and Type 2 diabetes. Twelve months after surgical oophorectomy, testosterone and gonadotrophin levels returned to appropriate values for menopausal status in all patients; however, no change in body weight was found. Fasting glucose levels slightly increased (P < 0·05) without any significant change in other metabolic parameters. In the woman with diabetes, a moderate decrease in haemoglobin A1c occurred. Red blood cell count and haematocrit values were normalized (P < 0·05, respectively).

Conclusion

Normalization of androgen levels achieved after surgical oophorectomy did not cause any significant change in body weight and insulin sensitivity. These findings may offer a different perspective on the impact of hyperandrogenaemia on metabolism.
Diagnostic and therapeutic dilemma associated with atypical glandular cells on liquid‐based cervical cytology
Authors: Chummun K. , Fitzpatrick M. , Lenehan P. , Boylan P. , Mooney E. , Flannelly G.
Published: May 2012

K. Chummun, M. Fitzpatrick, P. Lenehan, P. Boylan, E. Mooney and G. Flannelly  Diagnostic and therapeutic dilemma associated with atypical glandular cells on liquid‐based cervical cytology

Background:  In 2008, the management of women in Ireland with atypical glandular cells changed to immediate referral to colposcopy. The optimal management of these women is unclear. A balance between the detection of occult disease and overtreatment is required.

Methods:  Our study aim was to document the experience of this policy at the National Maternity Hospital, Dublin. Information from the computerized data management system was analysed with the statistical package SPSS.

Results:  In 2009, 156 women attended colposcopy following a single atypical glandular cell diagnosis on liquid‐based cytology. The mean age was 41 years. Thirty (19.2%) women had abnormal vaginal bleeding, 31 (19.9%) were smokers and 34 (21.8%) had received previous treatment. The colposcopy was satisfactory in 125 (80.1%) and unsatisfactory in 31 (19.9%). Cervical histology was available for 146 (93.6%) women: 57 excisional procedures and 89 diagnostic biopsies. Abnormal histology was detected in 46 women (31.5%). Four women (2.7%) had invasive cancer, five (3.4%) had adenocarcinoma in situ, 21 (14.4%) had cervical intraepithelial neoplasia (CIN) grade 2 or 3 and 16 (11.0%) had CIN1. No abnormality was detected in 100 women (68.5%), including 35 (61.4%) of those who had undergone excisional procedures. The colposcopic impression in this group was unsatisfactory in 10 women (28.6%), glandular abnormalities in six (17.1%), high‐ and low‐grade changes in 12 (34.2%) and six (17.1%) women, respectively, and normal in one (2.9%). The findings were essentially negative in the remaining 10 women: overall, 30 (19.2%) of the 156 women referred to colposcopy had at least CIN2.

Conclusion:  This study confirmed significant levels of high‐grade disease in women referred to colposcopy with atypical glandular cells on cytology. Concerns about undetected endocervical disease resulted in high levels of negative excisional biopsies. Alternative strategies, including endometrial sampling, human papillomavirus testing and discussion at clinicopathological meeting, should be considered.
Reovirus type‐2 infection in newborn DBA/1J mice reduces the development of late allergic asthma
Authors: Nakashima Tomomi , Hayashi Toshiharu , Mizuno Takuya
Published: May 2012

The aim of the present study was to determine whether or not the development of a helper T (Th) 1 response induced by Reovirus type‐2 (Reo‐2) infection would protect against the development of Th2‐mediated late allergic asthma. This hypothesis was examined by infecting one day old neonatal DB A/1J mice with Reo‐2 in an ovalbumin (OVA)‐induced late asthma model. Compared with the controls (either infected or uninfected mice with or without OVA sensitization and/or OVA challenge), Reo‐2 infection lessened the magnitude of the subsequent allergic Th2‐mediated late asthma. In infected mice with allergic late asthma, there was decreased infiltration of interleukin (IL)‐4+, IL‐5+, IL‐13+ and very late antigen (VLA)‐4+ lymphocytes, and eotaxin‐2+ and VLA‐4+ eosinophils, in both bronchial and bronchiolar lesions. Also the expression of vascular cell adhesion molecule (VCAM)‐1 and eotaxin‐2 on vascular endothelial cells was reduced. Moreover, the systemic production of IL‐4, IL‐5, tumour necrosis factor‐α and OVA‐specific IgE was reduced, whereas systemic IFN‐γ production was increased. In addition, there was no increase in IFN‐α production. Thus the present study suggests that systemic Reo‐2 infection at birth may reduce the development of subsequent late allergic asthma by the induction of a Th1 response. Therefore the potential suppressive mechanism(s) that might be induced by Reo‐2 infection in newborn mice and their effects on the development of late allergic asthma are discussed.
How occupational health care professionals experience evidence‐based guidelines in Finland: a qualitative study
Authors: Kinnunen‐Amoroso Maritta
Published: May 2012

Aims and objectives  Evidence‐based guidelines are currently the most relevant source of information in practice. The adherence to and use of guidelines is often influenced by attitudes towards the guidelines themselves, which have not been sufficiently explored in occupational health. This study examines the attitude of Finnish occupational nurses’ and doctors’ attitudes towards evidence‐based guidelines.

Methods  Ten occupational doctors and eight occupational nurses were interviewed in Southern Finland on their attitudes towards evidence‐based guidelines in 2009.

Results  The nurses were not very familiar with the concept of evidence‐based medicine. Rather, they used recommendations developed in their workplace or by their employer. The evidence base of these recommendations was not clear. The doctors considered the evidence‐based guidelines reliable and practical, but did not always act according to them. Participants felt that they did not have time to check guidelines during their working hours. Participants wished for clearer, shorter guidelines on occupational health care topics, which would help in their practical daily work and clarify roles in teamwork.

Conclusions  Based on these positive attitudes, the use of guidelines may be more common than it seems. The viewpoints of all occupational health professional groups should be taken into account in guideline development, particularly on the availability and usability of the guidelines.
Effects of focused ion beam milling on electron backscatter diffraction patterns in strontium titanate and stabilized zirconia
Authors: SAOWADEE N. , AGERSTED K. , BOWEN J.R.
Published: May 2012

This study investigates the effect of focused ion beam (FIB) current and accelerating voltage on electron backscatter diffraction pattern quality of yttria‐stabilized zirconia (YSZ) and Nb‐doped strontium titanate (STN) to optimize data quality and acquisition time for 3D‐EBSD experiments by FIB serial sectioning. Band contrast and band slope were used to describe the pattern quality. The FIB probe currents investigated ranged from 100 to 5000 pA and the accelerating voltage was either 30 or 5 kV. The results show that 30 kV FIB milling induced a significant reduction of the pattern quality of STN samples compared to a mechanically polished surface but yielded a high pattern quality on YSZ. The difference between STN and YSZ pattern quality is thought to be caused by difference in the degree of ion damage as their backscatter coefficients and ion penetration depths are virtually identical. Reducing the FIB probe current from 5000to 100 pA improved the pattern quality by 20% for STN but only showed a marginal improvement for YSZ. On STN, a conductive coating can help to improve the pattern quality and 5 kV polishing can lead to a 100% improvement of the pattern quality relatively to 30 kV FIB milling. For 3D‐EBSD experiments of a material such as STN, it is recommended to combine a high kV FIB milling and low kV polishing for each slice in order to optimize the data quality and acquisition time.