bluuebunny/crossref_metadata_2025 huggingface dataset:
A digital receiver module with direct data acquisition for magnetic resonance imaging systems
Authors: Tang Weinan , Sun Hongyu , Wang Weimin
Published: October 2012

A digital receiver module for magnetic resonance imaging (MRI) with detailed hardware implementations is presented. The module is based on a direct sampling scheme using the latest mixed-signal circuit design techniques. A single field-programmable gate array chip is employed to perform software-based digital down conversion for radio frequency signals. The modular architecture of the receiver allows multiple acquisition channels to be implemented on a highly integrated printed circuit board. To maintain the phase coherence of the receiver and the exciter in the context of direct sampling, an effective phase synchronization method was proposed to achieve a phase deviation as small as 0.09°. The performance of the described receiver module was verified in the experiments for both low- and high-field (0.5 T and 1.5 T) MRI scanners and was compared to a modern commercial MRI receiver system.
Effects of carbon nanofillers on enhancement of polymer composites
Authors: Chen Wen-Jia , Zhu Yue-Feng , Wang Sheng-Xi , Pei Wen-Fei , Jiang Yin
Published: October 2012

Different carbon nanofillers derived from carbon nanotubes and graphite were fabricated and characterized to investigate their effects on enhancement of polymer composites. It could be concluded that a better enhancement effect would be achieved when the nanofillers possessed a higher O/C ratio and more wrinkled surface. As another key factor affecting the mechanical properties of composites, the dispersion status of nanofillers in matrix was quantitatively characterized by measuring the relative transmittance (RT) of the suspension. The RT curve varying with time was fitted by a sigmoidal growth function and a key parameter was calculated to discribe the dispersibility of the nanofillers. It was found that the dispersibility of nanofillers was approximately proportional to the enhancement effect on the resulted composites. So, the mechanical properties of the composites could be estimated by investigating the dispersibility of nanofillers in matrix.
A generalized Irving–Kirkwood formula for the calculation of stress in molecular dynamics models
Authors: Yang Jerry Zhijian , Wu Xiaojie , Li Xiantao
Published: October 2012

In non-equilibrium molecular dynamics simulations, continuum mechanics quantities can be computed from the position and momentum of the particles based on the classical Irving–Kirkwood formalism. For practical purposes, the implementations of Irving–Kirkwood formulas often involve a spatial averaging using a smooth kernel function. The resulting formula for the stress has been known as Hardy stress. Usually results obtained this way still need to be further processed to reduce the fluctuation, e.g., by ensemble or time averaging. In this paper we extend Hardy's formulas by systematically incorporating both spatial and temporal averaging into the expression of continuum quantities. The derivation follows the Irving–Kirkwood formalism, and the average quantities still satisfy conservation laws in continuum mechanics. We will discuss the selection of kernel functions and present several numerical tests.
High temperature finite-size effects in the magnetic properties of Ni nanowires
Authors: López-Ruiz R. , Magén C. , Luis F. , Bartolomé J.
Published: October 2012

The magnetic response of nickel nanowires embedded in porous alumina has been investigated in a wide temperature range, from 5 K up to 700 K. Hysteresis loops and magnetization isotherms were measured on samples of Ni nanowires with different sizes and morphologies up to the Curie temperature. At room temperature, the magnetic response shows evidences of a particle-to-wire crossover above an aspect ratio L/D = 4.3. The magnetic coercivity of high aspect ratio Ni nanowires in the direction parallel to the nanowires has a maximum at T ≈ 400 K, while in the parallel direction Hc decreases continuously with increasing temperature. It is explained in terms of competing anisotropies, magnetocrystalline and magnetoelastic. The expansion of the aluminium support of the membrane plays a fundamental role in the temperature dependence of the coercive field. We find also that TC progressively decreases due to a finite-size effect as the wire's diameter decreases.
Nanoscale ferroelectric tunnel junctions based on ultrathin BaTiO3 film and Ag nanoelectrodes
Authors: Gao X. S. , Liu J. M. , Au K. , Dai J. Y.
Published: October 2012

In this work, Ag nanoisland electrodes (nanoelectrodes) have been deposited on top of ultrathin ferroelectric BaTiO3 (BTO) films to form a nanoscale metal-ferroelectric-metal tunnel junction by integrating growth techniques of nanocluster beam source and laser-molecular beam epitaxy. The ultrathin BTO films (∼3 nm thick) exhibit both apparent ferroelectric polarization reversal and ferroelectric tunneling related resistive switching behaviors. The introducing of Ag nanoislands (∼20 nm in diameter) as top electrode substantially enhances the tunneling current and alters the symmetry of I-V hysteresis curves. The enhanced tunneling current is likely due to the reduction in tunneling barrier height and an increase in effective tunneling area by Ag nano-electrodes, while the improved symmetric in I-V curve may be attributed to the variation of electrode-oxide contact geometry.
Colossal low-frequency resonant magnetomechanical and magnetoelectric effects in a three-phase ferromagnetic/elastic/piezoelectric composite
Authors: Liu Guoxi , Li Xiaotian , Chen Jianguo , Shi Huaduo , Xiao Wenlei , Dong Shuxiang
Published: October 2012

Colossal low-frequency resonant magnetomechanical (MM) and magnetoelectric (ME) coupling effects have been found in a three-phase composite made of Pb(Zr,Ti)O3 ceramic fibers/phosphor copper-sheet unimorph and NdFeB magnets. The experimental results revealed that the ferromagnetic/elastic/piezoelectric three-phase composite with a cantilever beam structure could show huge bending MM coefficient of ∼145.9 × 10−3/Oe (unit in bending radian per Oe) and ME voltage coefficient of ∼16 000 V/cm·Oe at the first-order bending resonance frequency of ∼5 Hz. The achieved results related to ME effect are at least one order of magnitude higher over those of other ME materials and devices reported ever. The extremely strong MM and ME couplings in the three-phase composite are due to strong magnetic force moment effect induced by the interaction between NdFeB magnets and the applied magnetic field, and further resonant enhancement via the strain-mediated phosphor copper-sheet with a relatively high mechanical quality factor.
Nonlinear optical mass sensor with an optomechanical microresonator
Authors: Li Jin-Jin , Zhu Ka-Di
Published: October 2012

Mechanical oscillators have been widely used in mass sensing due to the direct relationship of the frequency-shift and mass-change. A conventional method for detecting the mass of deposited sample is to exploit the frequency variation of mechanical resonator in the linear optical regime. In the present letter, we demonstrate a nonlinear optical mass sensor with an optomechanical microresonator which will provide a route towards the use of cavity optomechanical system in biomedical sensors, deposition monitors, chemical reaction monitors and other nonlinear measurement fields. Based on the current experimental conditions, the nonlinear optical mass sensor proposed here can be achieved by experiments.
Slow magnetic dynamics in the K3M3IIM2IIIF15 multiferroic system
Authors: Pajić Damir , Jagličić Zvonko , Trontelj Zvonko
Published: October 2012

K 3 Fe 5 F 15 is a multiferroic material belonging to the K3M3IIM2IIIF15 family. Zero-field cooled and field cooled magnetization measured as a function of temperature demonstrate magnetic transition in K3Fe5F15, K3Fe3Cr2F15, and K3Cu3Fe2F15. Complementary to this, the magnetic behavior below the magnetic transition was studied via magnetic relaxation at different temperatures after switching magnetic field from H to −H. A slow change of magnetization on the hours time scale was observed and it was best described by a logarithmic time dependence for all three compounds over a broad temperature and field range. It follows that a distribution of magnetic moments over anisotropy barriers, which block the magnetic moments against reorientation, is present. We introduced a model of thermal activation of the magnetic moments of regions distributed over the barriers to describe the temperature and field dependence of the relaxation parameters. The dimensions of these magnetic regions were estimated to be of nanometer size.
Kinetics of interdiffusion in semiconductor ternary quantum dots
Authors: Han Xu , Pandey Sumeet C. , Maroudas Dimitrios
Published: October 2012

We develop a one-dimensional transient model of species transport in ternary quantum dots (QDs) and implement the model for analysis of group-VI species interdiffusion kinetics in ZnSe1−xSx nanocrystals. We use the model results for the interpretation of x-ray photoelectron spectroscopy data for the group-VI species near-surface concentration evolution during thermal annealing of ZnSe1−xSx QDs with a ZnSe/ZnS core/shell initial configuration. The model provides an excellent fitting of the experimental data, which is used to derive transport coefficients and thermal activation barriers for diffusion in the ternary QDs.
Effect of a short weak prepulse on laser-triggered front-surface heavy-ion acceleration
Authors: Bochkarev S. G. , Golovin G. V. , Uryupina D. S. , Shulyapov S. A. , Andriyash A. V. , Bychenkov V. Yu. , Savel'ev A. B.
Published: October 2012

A suppression of light-ion acceleration (from surface water contaminants) was observed when a moderate-intensity subpicosecond laser pulse was focused on a thick metal target. Simultaneously, an effective generation of high-energy multicharge ions of the target material (Fe) was experimentally observed. A numerical simulation based on the Boltzmann–Vlasov–Poisson model revealed that this is due to the very specific regime of cleaning contaminants from the target surface by the short weak prepulse preceding the main pulse by more than 10 ns and having an intensity below the surface breakdown threshold. Because this prepulse causes the contaminant layer to boil explosively, a low-density gap forms above the target surface. These conditions are consequently favorable for boosting the energy of heavy ions.
Trapping of diffusing germanium by silicon excess co-implanted into fused silica
Authors: Barba D. , Demarche J. , Martin F. , Terwagne G. , Ross G. G.
Published: October 2012

The trapping of germanium by silicon atoms, successively implanted into fused silica, is evidenced after thermal annealing at 1150 °C. Rutherford backscattering spectroscopy and Raman measurements reveal a linear increase of remaining Ge concentration with the co-implanted Si fluence, accompanied by an increase of the Ge-Ge bond density, respectively. Comparison of Ge concentration profiles with scanning electron microscopy images shows the formation of nanoclusters, resulting from the accumulation of Ge within the region containing a greater concentration of co-implanted Si, whereas nanocavities, indicative of Ge release from nanostructures, are dominant in deeper sample region of lower Si excess concentration.
Communication: Explicitly correlated four-component relativistic second-order Møller-Plesset perturbation theory
Authors: Ten-no Seiichiro , Yamaki Daisuke
Published: October 2012

We propose explicitly correlated Ansatz for four-component relativistic methods within the framework of the no-pair approximation. Kinetically balanced geminal basis is derived to satisfy the cusp conditions in the non-relativistic limit based on the Lévy-Leblend-like equation. Relativistic variants of strong-orthogonality projection operator (Ansätze 2α and 2β) suitable for practical calculations are introduced by exploiting the orthogonal complement of the large-component basis. A pilot implementation is performed for the second order Møller-Plesset perturbation theory.
Communication: On the isotope anomaly of nuclear quadrupole coupling in molecules
Authors: Filatov Michael , Zou Wenli , Cremer Dieter
Published: October 2012

The dependence of the nuclear quadrupole coupling constants (NQCC) on the interaction between electrons and a nucleus of finite size is theoretically analyzed. A deviation of the ratio of the NQCCs obtained from two different isotopomers of a molecule from the ratio of the corresponding bare nuclear electric quadrupole moments, known as quadrupole anomaly, is interpreted in terms of the logarithmic derivatives of the electric field gradient at the nuclear site with respect to the nuclear charge radius. Quantum chemical calculations based on a Dirac-exact relativistic methodology suggest that the effect of the changing size of the Au nucleus in different isotopomers can be observed for Au-containing molecules, for which the predicted quadrupole anomaly reaches values of the order of 0.1%. This is experimentally detectable and provides an insight into the charge distribution of non-spherical nuclei.
Optical toroidal dipolar response by an asymmetric double-bar metamaterial
Authors: Dong Zheng-Gao , Zhu J. , Rho Junsuk , Li Jia-Qi , Lu Changgui , Yin Xiaobo , Zhang X.
Published: October 2012

We demonstrate that the toroidal dipolar response can be realized in the optical regime by designing a feasible nanostructured metamaterial, comprising asymmetric double-bar magnetic resonators assembled into a toroid-like configuration. It is confirmed numerically that an optical toroidal dipolar moment dominates over other moments. This response is characterized by a strong confinement of an E-field component at the toroid center, oriented perpendicular to the H-vortex plane. The resonance-enhanced optical toroidal response can provide an experimental avenue for various interesting optical phenomena associated with the elusive toroidal moment.
Influence of target composition and deposition temperature on the domain structure of BiFeO3 thin films
Authors: Guo Rui , You Lu , Motapothula M. , Zhang Zhen , Breese M. B. H. , Chen Lang , Wu Di , Wang Junling
Published: October 2012

Domain structure of BiFeO3 thin films can be controlled by adjusting the target composition or the substrate temperature during pulsed laser deposition. Decreasing Bi content in the target or increasing substrate temperature changes the domain structure of BiFeO3 from 71° to 109°. We suggest that a combination of interface effect and defect induced internal field causes this evolution.
Carrier recombination lifetime in InAs thin films bonded on low-k flexible substrates
Authors: Suzuki Toshi-kazu , Takita Hayato , Nguyen Cong Thanh , Iiyama Koichi
Published: October 2012

We investigated carrier recombination in InAs thin films obtained by epitaxial lift-off and van der Waals bonding on low-k flexible substrates. Photoconductors are fabricated from the InAs thin films bonded on flexible substrates, and also from films grown on GaAs(001) substrates. By irradiation of 1.55-μm-wavelength laser light with intensity modulation, we characterized frequency responses of the InAs photoconductors by S-parameter measurements. From an analysis of the frequency dependence of the S-parameters, we obtained carrier recombination lifetimes, which are long for the InAs thin films bonded on flexible substrates in comparison with those grown on GaAs(001), attributed to the lower dislocation density in the former.
Hydrodynamics coalescence collision of three liquid drops in 3D with smoothed particle hydrodynamics
Authors: Acevedo-Malavé Alejandro
Published: October 2012

The Smoothed Particle Hydrodynamics method (SPH) has been useful to model continuous fluid. This method is employed to obtain approximate numerical solutions of the equations in fluid dynamics by replacing the fluid with a set of particles. These particles may be interpreted as corresponding to interpolation points from which properties of the fluid can be determined. The SPH method is particularly useful when the fluid motion produces a big deformation and a large velocity of the whole fluid. In this study, the SPH method is applied to simulate for the first time the hydrodynamic collision of three equal-size liquid drops in the three-dimensional space. Ranges of value for the droplets collision velocity are chosen giving rise to the following different results for the collision: permanent coalescence, fragmentation, and flocculation of the drops. The velocity vector fields formed inside the drops during the collision process are presented. Three possible scenarios for fragmentation of liquid drops are shown. Multiple satellite drops arise from the ligaments on the surface of the formed bigger drop.
Species diversity and genetic differentiation of stygofauna (Syncarida:Bathynellacea) across an alluvial aquifer in north-eastern Australia
Authors: Cook B. D. , Abrams K. M. , Marshall J. , Perna C. N. , Choy S. , Guzik M. T. , Cooper S. J. B.
Published: October 2012

Recent research suggests that alluvial aquifers in southern and eastern Australia may contain a diverse subterranean aquatic fauna (i.e. stygofauna). However, to date only a limited number of alluvial aquifers have been studied and little molecular data are available to assess species-level diversity and spatial patterns of genetic variation within stygofaunal species. In this paper, we present the initial results of a stygofaunal survey of the Burdekin River alluvial aquifer in Queensland, extending the northern range of alluvial aquifers along the east coast of Australia that have been investigated. The survey resulted in the collection of bathynellid stygofauna (Syncarida: Bathynellacea) and genetic analyses were conducted to determine species level diversity using the mitochondrial cytochrome oxidase subunit I (COI) gene. We further investigated the phylogenetic relationships of the species with bathynellids from western and southern Australia to assess the generic status of species. Four highly divergent COI lineages within the Parabathynellidae and one lineage within the Bathynellidae were found. These lineages did not group within any described genera, and phylogenetic analyses indicated that both local radiations and the retention of a lineage that was more apical in the genealogy account for the diversity within the Parabathynellidae in the Burdekin River alluvial aquifer. Most COI lineages were sampled from only a single bore, although one taxon within the Parabathynellidae was found to be more widespread in the aquifer. Haplotypes within this taxon were not shared among bores (ΦST = 0.603, P < 0.001). Overall, the high species diversity for bathynellaceans from an alluvial aquifer reported here, and surveys of bathynellaceans in several other alluvial systems in south-eastern Australia, suggests that groundwater ecosystems of eastern Australia may contain high stygofaunal diversity by Australian and world standards, particularly at the generic level for parabathynellids.
Role of protons in sugar binding to LacY
Authors: Smirnova Irina , Kasho Vladimir , Sugihara Junichi , Vázquez-Ibar José Luis , Kaback H. Ronald
Published: October 2012

WT lactose permease of
Escherichia coli
(LacY) reconstituted into proteoliposomes loaded with a pH-sensitive fluorophore exhibits robust uphill H
+
translocation coupled with downhill lactose transport. However, galactoside binding by mutants defective in lactose-induced H
+
translocation is not accompanied by release of an H
+
on the interior of the proteoliposomes. Because the p
K
a
value for galactoside binding is ∼10.5, protonation of LacY likely precedes sugar binding at physiological pH. Consistently, purified WT LacY, as well as the mutants, binds substrate at pH 7.5–8.5 in detergent, but no change in ambient pH is observed, demonstrating directly that LacY already is protonated when sugar binds. However, a kinetic isotope effect (KIE) on the rate of binding is observed, indicating that deuterium substitution for protium affects an H
+
transfer reaction within LacY that is associated with sugar binding. At neutral pH or pD, both the rate of sugar dissociation (k
off
) and the forward rate (k
on
) are slower in D
2
O than in H
2
O (KIE is ∼2), and, as a result, no change in affinity (
K
d
) is observed. Alkaline conditions enhance the effect of D
2
O on k
off
, the KIE increases to 3.6–4.0, and affinity for sugar increases compared with H
2
O. In contrast, LacY mutants that exhibit pH-independent high-affinity binding up to pH 11.0 (e.g., Glu325 → Gln) exhibit the same KIE (1.5–1.8) at neutral or alkaline pH (pD). Proton inventory studies exhibit a linear relationship between k
off
and D
2
O concentration at neutral and alkaline pH, indicating that internal transfer of a single H
+
is involved in the KIE.
Prédire la position de l’adjectif épithète en français
Authors: Thuilier Juliette , Fox Gwendoline , Crabbé Benoît
Published: October 2012

The paper provides a quantitative study (on the syntax) of the placement alternation for the adjective within the noun phrase in French. Taking the hypothesis that position constraints are mostly preferential as a starting point, we develop a methodology based on statistical inference in order to provide a formal account of the relative importance of three different groups of constraints: combinatorial, frequency and length, and lexical constraints. The study highlights the clear importance of lexical constraints for deciding the effective position of the adjective within the noun phrase. We conclude the paper by bringing some elements of discussion for two issues: the interaction between lexicon and grammar (or storage versus computation) and the underlying methodology for a probability-based study of syntax.
Le statut des séquences “N+N à N2 productif”
Authors: Van Goethem Kristel
Published: October 2012

This article investigates the status of French N+N constructions in which the N2 productively combines with different N1’s (e.g. réunion marathon ‘marathon meeting’, examen marathon ‘marathon exam’, plaidoyer marathon ‘marathon plea’, etc). In the literature, this construction has been analyzed in very different ways, going from regular N+N compounding to the syntactic combination of a noun with a second noun converted into an adjective. In a first section, the arguments in favour of these different analyses are discussed. The second section is devoted to a specific case study in which the construction N-clé ‘key N’ (mot-clé ‘key word’, fonction-clé ‘key function’, élément-clé ‘key element’, etc.) is subjected to a profound semantic, orthographic, morphological and syntactic analysis. It will be observed that in recent uses the N-clé construction has developed some new syntactic properties that might be accounted for by a process of degrammaticalization.
How English-origin nouns (do not) pluralize in French
Authors: Saugera Valérie
Published: October 2012

While French and English share the same pluralization morpheme, a dictionary corpus sanctioned by press usage reveals that a small set of nominal anglicisms, particularly compounds, fail to receive inflection in French (e.g., des black-jack
s
, des happy end
s
, des beagle
s vs. des black-out, des has been, des people). This study interprets patterns of inflectional variation and reveals inflection-inhibiting constraints for these bare borrowings and thus contributes to explaining the little-researched morphology of anglicisms in French. The findings clearly demonstrate that the absence of inflection, seemingly atypical, is systematically rooted in the parameters of French morphology. The analysis simultaneously though secondarily documents phases, mechanisms, and processes of integration for contemporary borrowing — e.g., patterns of simplification with regularization of irregularities, a well-attested contact phenomenon; borrowing as a non-homogeneous phenomenon (English loans vs. other-language loans); and anglicisms as tools for creative, playful language.
Syntomic cohomology and Beilinson’s Tate conjecture for 𝐾₂
Authors: Asakura Masanori , Sato Kanetomo
Published: October 2012

We study Beilinson’s Tate conjecture forK2K_2using the theory of syntomic cohomology. As an application, we construct integral indecomposable elements ofK1K_1of elliptic surfaces. Moreover, we give the first example of a surfaceXXwithpg≠0p_g\ne 0over app-adic field such that the torsion ofCH0(X)\mathrm {CH}_0(X)is finite.
Histology shows that elongated neck ribs in sauropod dinosaurs are ossified tendons
Authors: Klein Nicole , Christian Andreas , Sander P. Martin
Published: October 2012

The histology of cervical ribs of Sauropoda reveals a primary bone tissue, which largely consists of longitudinally oriented mineralized collagen fibres, essentially the same tissue as found in ossified tendons. The absence of regular periosteal bone and the dominance of longitudinal fibres contradict the ventral bracing hypothesis (VBH) postulated for sauropod necks. The VBH predicts histologically primary periosteal bone with fibres oriented perpendicular to the rib long axis, indicative of connective tissue between overlapping hyperelongated cervical ribs. The transformation of the cervical ribs into ossified tendons makes the neck more flexible and implies that tension forces acted mainly along the length of the neck. This is contrary to the VBH, which requires compressive forces along the neck. Tension forces would allow important neck muscles to shift back to the trunk region, making the neck much lighter.
In the eye of the beholder: visual mate choice lateralization in a polymorphic songbird
Authors: Templeton Jennifer J. , Mountjoy D. James , Pryke Sarah R. , Griffith Simon C.
Published: October 2012

Birds choose mates on the basis of colour, song and body size, but little is known about the mechanisms underlying these mating decisions. Reports that zebra finches prefer to view mates with the right eye during courtship, and that immediate early gene expression associated with courtship behaviour is lateralized in their left hemisphere suggest that visual mate choice itself may be lateralized. To test this hypothesis, we used the Gouldian finch, a polymorphic species in which individuals exhibit strong, adaptive visual preferences for mates of their own head colour. Black males were tested in a mate-choice apparatus under three eye conditions: left-monocular, right-monocular and binocular. We found that black male preference for black females is so strongly lateralized in the right-eye/left-hemisphere system that if the right eye is unavailable, males are unable to respond preferentially, not only to males and females of the same morph, but also to the strikingly dissimilar female morphs. Courtship singing is consistent with these lateralized mate preferences; more black males sing to black females when using their right eye than when using their left. Beauty, therefore, is in therighteye of the beholder for these songbirds, providing, to our knowledge, the first demonstration of visual mate choice lateralization.
The debt of John Ray and Martin Lister to Guillaume Rondelet of Montpellier
Authors: Lewis Gillian
Published: October 2012

The fame of its medical university and its reputation for field botany attracted visitors from all over Europe to seventeenth-century Montpellier. It was there that Martin Lister first made the acquaintance of John Ray in 1665. Twenty years later, in London, they cooperated in the production of the ambitious and lavishly illustrated
Historia Piscium
based on the notes of the late Francis Willughby. Ray, Lister and others contributed additional material. In their own work on fishes, cetaceans and shellfish Ray and Lister were considerably indebted to the
Libri de piscibus marinis
of an earlier Montpellier professor, Guillaume Rondelet, whose Aristotelian/Galenic approach to the study of medicine and living things was distinguished by a quite exceptional level of knowledge about aquatic species, based on a secure grasp of the classical and contemporary literature, but above all on his own observations in rivers, lakes, lagoons and the open sea, and his domestication (and dissection) of marine species in ponds and aquaria at his country house. Rondelet's book proved useful to Ray and to Lister as a work of reference, as a stimulus for reflection on biological problems, as an aid to nomenclature, as a source of precise descriptions of species, in both words and pictures, as a model to be improved upon in taxonomy, as a warning against reliance on hearsay, and as a valuable account of observations and experiments. Ray used it in much the same way as he used the work of those sixteenth-century botanists who met with his approval. Several of these had been Rondelet's pupils.
Bat echolocation calls facilitate social communication
Authors: Knörnschild Mirjam , Jung Kirsten , Nagy Martina , Metz Markus , Kalko Elisabeth
Published: October 2012

Bat echolocation is primarily used for orientation and foraging but also holds great potential for social communication. The communicative function of echolocation calls is still largely unstudied, especially in the wild. Eavesdropping on vocal signatures encoding social information in echolocation calls has not, to our knowledge, been studied in free-living bats so far. We analysed echolocation calls of the polygynous batSaccopteryx bilineataand found pronounced vocal signatures encoding sex and individual identity. We showed experimentally that free-living males discriminate approaching male and female conspecifics solely based on their echolocation calls. Males always produced aggressive vocalizations when hearing male echolocation calls and courtship vocalizations when hearing female echolocation calls; hence, they responded with complex social vocalizations in the appropriate social context. Our study demonstrates that social information encoded in bat echolocation calls plays a crucial and hitherto underestimated role for eavesdropping conspecifics and thus facilitates social communication in a highly mobile nocturnal mammal.
How far bowalization affects phytodiversity, life forms and plant morphology in Sub‐humid tropic in West Africa
Authors: Padonou Elie A. , Assogbadjo Achille E. , Bachmann Yvonne , Sinsin Brice
Published: October 2012

Bowal or ferricrete, the final of land degradation, occurred only in tropical region. This study aimed at assessing the effects of bowalization on phytodiversity, life forms and morphological response of plant species using Combretum nigricans Leprieur ex Guill. & Perr. as a case study. Morphological parameters (height, number of stems, number of branches, diameter at breast height and crown diameter) of C. nigricans were determined in the sub‐humid zone of Benin. Plant communities were determined according to Multi‐Response Permutation Procedures analysis. Plant communities were more diversified on sand‐clay and concretion soils (control) compared with those described on bowal. C. nigricans developed more stems (3.6 ± 1.4 stems vs. 1.3 ± 0.4 stems), more branches (5.9 ± 2.4 branches vs. 3.2 ± 0.6 branches) and large crown diameter (5 ± 1.48 m vs. 3.4 ± 1.2 m) on bowal than on sand‐clay soil. The best adapted life forms on bowal were therophytes. Bowalization induced loss of phytodiversity, changes in species life forms and provoked local adaptation of tree species.
Case report and literature review of chronic neuropathic pain associated with peripheral venous cannulation
Authors: Gohil S. , Balasubramanian S.
Published: October 2012

We report a case of neuropathic pain following peripheral venous cannulation for an elective surgical procedure and discuss the various mechanisms by which this could occur. The mostly likely trigger in this case is phlebitis as the onset of symptoms coincided with the local infection. Neuropathic pain can occur following innocent interventions and its impact on the patient’s quality of life may be reduced by timely recognition and management.
Hepatitis B virus infection is associated with deletion of chromosome 8p in multiple myeloma
Authors: Becker Nikolaus , Byl Anne , Friedrich Susanne , Jauch Anna , Schnitzler Paul , Egerer Gerlinde , Ho Anthony D , Goldschmidt Hartmut , Neben Kai
Published: October 2012

Serological analyses within epidemiological cohort and case‐control studies indicate to an association between HBV infection and risk of multiple myeloma (MM). To verify the relationship with an independent approach, we investigated the correlation between HBV positivity and chromosomal aberrations within 680 patients of the National Center for Tumor Diseases Heidelberg for which the serological HBV status (HBsAg and anti‐HBc) and FISH data for five gains (1q21, 9q34, 11q23, 15q22, 19q13), five losses (6q21, 8p21, 13q14, 17p13, 22q11), and three IgH translocations [t(4,14), t(11,14), t(14,16)] were available. Deletion of 8p21 and 13q14 were shown associated with HBV positivity within hepatocellular carcinoma in other investigations. In the present evaluation, the odds ratio for loss of 8p21 was significantly elevated (OR = 2.74, 95% CL = 1.36–5.50, P = 0.0048) and for loss of 13q14 non‐significantly increased (OR = 1.40, 95% CL = 0.74–2.65) in anti‐HBc positive patients. The results provide further support for a role of HBV infection in the pathogenesis of MM.
A novel TRB@/NOTCH1 fusion gene in T‐cell lymphoblastic lymphoma with t(7;9)(q34;q34)
Authors: Yamamoto Katsuya , Nakamachi Yuji , Yakushijin Kimikazu , Miyata Yoshiharu , Okamura Atsuo , Kawano Seiji , Matsuoka Hiroshi , Minami Hironobu
Published: October 2012

Background: In T‐cell acute lymphoblastic leukemia/lymphoma (T‐ALL/LBL), activating mutations of NOTCH1 are observed in more than 50% of cases, whereas the t(7;9)(q34;q34) involving NOTCH1 at 9q34 and TRB@ at 7q34 is an extremely rare but recurrent translocation. Patient: A 41‐year‐old male with a large mediastinal mass, pleural effusion, and lymphadenopathy was diagnosed as having T‐LBL. Lymphoma cells were positive for CD4, CD8, CD2, CD3, CD5, CD7, CD10, and TdT. Results: G‐banding and spectral karyotyping of pleural effusion cells showed 47,XY,dup(1)(q21q32),t(7;9)(q34;q34),+20. Genomic polymerase chain reaction (PCR) revealed that the 5′ end of TRB@ J1‐5 was connected with the middle of NOTCH1 exon 25 (434 bp downstream from its 5′ end) in a ‘head‐to‐head’ configuration on the der(9)t(7;9), although nine extra bases were inserted between the two genes. Reverse transcription‐PCR confirmed expression of the TRB@/NOTCH1 fusion transcripts. Similarly, the 5′ end of J1‐5 was fused to the shortened exon 25 with nine extra bases. The NOTCH1 breakpoint in exon 25 was very close to transcription start sites of deleted Notch1 in murine T‐ALL. Conclusions: The TRB@/NOTCH1 fusion gene with a NOTCH1 breakpoint in exon 25, which has not previously been detected in four other reported cases with t(7;9), could lead to aberrant expression of the truncated NOTCH1 by TRB@ enhancer elements. The resultant NOTCH1 receptor deleting most of the extracellular domain may be implicated in the pathogenesis of T‐LBL by ligand‐independent, constitutive activation of the NOTCH1 pathway, suggesting avenues for future therapy with γ‐secretase inhibitors.
A sprayable luminescent pH sensor and its use for wound imaging in vivo
Authors: Schreml Stephan , Meier Robert J. , Weiß Katharina T. , Cattani Julia , Flittner Dagmar , Gehmert Sebastian , Wolfbeis Otto S. , Landthaler Michael , Babilas Philipp
Published: October 2012

Non‐invasive luminescence imaging is of great interest for studying biological parameters in wound healing, tumors and other biomedical fields. Recently, we developed the first method for 2D luminescence imaging of pH in vivo on humans, and a novel method for one‐stop‐shop visualization of oxygen and pH using the RGB read‐out of digital cameras. Both methods make use of semitransparent sensor foils. Here, we describe a sprayable ratiometric luminescent pH sensor, which combines properties of both these methods. Additionally, a major advantage is that the sensor spray is applicable to very uneven tissue surfaces due to its consistency. A digital RGB image of the spray on tissue is taken. The signal of the pH indicator (fluorescein isothiocyanate) is stored in the green channel (G), while that of the reference dye [ruthenium(II)‐tris‐(4,7‐diphenyl‐1,10‐phenanthroline)] is stored in the red channel (R). Images are processed by rationing luminescence intensities (G/R) to result in pseudocolor pH maps of tissues, e.g. wounds.
Net greenhouse gas balance in response to nitrogen enrichment: perspectives from a coupled biogeochemical model
Authors: Lu Chaoqun , Tian Hanqin
Published: October 2012

Increasing reactive nitrogen (N) input has been recognized as one of the important factors influencing climate system through affecting the uptake and emission of greenhouse gases (GHG). However, the magnitude and spatiotemporal variations of N‐induced GHG fluxes at regional and global scales remain far from certain. Here we selected China as an example, and used a coupled biogeochemical model in conjunction with spatially explicit data sets (including climate, atmospheric CO2, O3, N deposition, land use, and land cover changes, and N fertilizer application) to simulate the concurrent impacts of increasing atmospheric and fertilized N inputs on balance of three major GHGs (CO2, CH4, and N2O). Our simulations showed that these two N enrichment sources in China decreased global warming potential (GWP) through stimulating CO2 sink and suppressing CH4 emission. However, direct N2O emission was estimated to offset 39% of N‐induced carbon (C) benefit, with a net GWP of three GHGs averaging −376.3 ± 146.4 Tg CO2 eq yr−1 (the standard deviation is interannual variability of GWP) during 2000–2008. The chemical N fertilizer uses were estimated to increase GWP by 45.6 ± 34.3 Tg CO2 eq yr−1 in the same period, and C sink was offset by 136%. The largest C sink offset ratio due to increasing N input was found in Southeast and Central mainland of China, where rapid industrial development and intensively managed crop system are located. Although exposed to the rapidly increasing N deposition, most of the natural vegetation covers were still showing decreasing GWP. However, due to extensive overuse of N fertilizer, China's cropland was found to show the least negative GWP, or even positive GWP in recent decade. From both scientific and policy perspectives, it is essential to incorporate multiple GHGs into a coupled biogeochemical framework for fully assessing N impacts on climate changes.
The ALK translocation in advanced non‐small‐cell lung carcinomas: preapproval testing experience at a single cancer centre
Authors: Conde Esther , Angulo Bárbara , Izquierdo Elisa , Muñoz Luna , Suárez‐Gauthier Ana , Plaza Carlos , Dominguez Nuria , Torres Maribel , Madrigal Luis , Rubio‐Viqueira Belén , Belda‐Iniesta Cristobal , Hidalgo Manuel , López‐Ríos Fernando
Published: October 2012

Aims

To study the ALK translocation in patients with advanced non‐small‐cell lung carcinomas (NSCLCs) seen at a European cancer centre, and its association with EGFR mutations, KRAS mutations and MET amplification.

Methods and results

The study included samples from 86 patients diagnosed with advanced NSCLC. ALK fluorescence in‐situ hybridization (FISH) was performed using the ALK break‐apart probe set (Vysis). ALK FISH‐positive cases were defined as those with more than 15% break‐apart signals or isolated red signals in 50 cells. EGFR and KRAS mutations were determined by direct sequencing. All ALK‐positive cases were analysed retrospectively for MET amplification using a FISH assay, and for ALK mutations by sequencing. We found nine (10.5%) ALK‐positive cases, all in adenocarcinomas and the majority in female patients (88.9%). Signet ring cells were observed in four (44.4%) of the nine patients. None of the ALK translocated cases showed MET amplifications or EGFR, KRAS and ALK mutations.

Conclusions

The prevalence of ALK translocation in an unselected population of European patients with advanced NSCLCs was 10%. This alteration was mutually exclusive with EGFR and KRAS mutations, as well as with MET amplification. If multiplexing is considered at the preanalytical phase, lung biopsy specimens are sufficient for performing several predictive assays.
Hotspots of exotic free‐spawning sex: man‐made environment facilitates success of an invasive seastar
Authors: Ling Scott D. , Johnson Craig R. , Mundy Craig N. , Morris Alice , Ross D. Jeff
Published: October 2012

1. The introduction of exotic species to new areas poses a major threat to the environment. For those introduced species that establish and survive beyond the short term, the opportunities to manage the risk of continuing spread often rest with limiting reproductive output. The introduced northern Pacific seastar Asterias amurensis is an ecologically important pest that has established in the Derwent Estuary (Australia). Driven by oversupply of bivalve prey, it is persistent, abundant and fecund when associated with man‐made structures such as docks, marinas, jetties and piers, that is, ‘wharves’.

2. As a free‐spawning invertebrate, fertilization by A. amurensis is a critical life‐history stage constrained by strong Allee effects. Eggs must be released in close proximity to sperm sources because the chances of achieving fertilization drastically reduce with increasing distances of spawner separation.

3. Investigation of zygote production in the Derwent Estuary using a spatially explicit model of free‐spawning fertilization shows that A. amurensis at wharves, while representing <10% of the total population in the estuary and concentrated in <0·1% of the total area, may contribute >90% of total zygote production. Given the seastars’ long‐lived and highly dispersive larvae, we show that wharves not only represent important sites of invasion but also facilitate propagule pressure promoting secondary invasions.

4. Synthesis and applications. In the absence of effective pest control solutions, focusing on reproductive hotspots has the potential to reduce further spread of established marine pests and to alleviate ongoing ecological impacts. In the case of the northern Pacific seastar, elimination of highly localized wharf populations annually prior to spawning can reduce overall zygote production by up to estimated ∼90%. The long‐term protection of key sources of larval production is a common goal for marine reserve design and fisheries management. However, the same concept but in reverse, whereby larval production is minimized at key sources, could be effective in the management of introduced pests in subtidal marine environments.
Multi‐level functional responses for wildlife conservation: the case of threatened caribou in managed boreal forests
Authors: Moreau Guillaume , Fortin Daniel , Couturier Serge , Duchesne Thierry
Published: October 2012

1. The selection for particular habitat patches can vary as a function of local and regional levels of anthropogenic disturbance. Although such functional responses can better reveal habitat loss for species of precarious status faced with dwindling resources, they remain rarely used in conservation planning. We show that functional responses can occur at multiple levels, even as nested hierarchies, and that they can explain the plasticity in habitat selection observed in threatened forest‐dwelling caribou Rangifer tarandus caribou, within and among home‐ranges.

2. Twenty‐seven caribou were followed with global positioning system collars between 2005 and 2010. Generalized linear mixed models served as the basis from which we built multi‐level functional responses characterizing how caribou alter their selection for closed‐canopy conifer forests, depending upon the availability of these forests and the amount of cutovers and roads.

3. Caribou increased their selection for closed‐canopy conifer forests in areas of their home‐range that were comprised of a high proportion of recent cutovers during calving and summer and of high closed‐canopy conifer forests during winter. Also, caribou that were established in highly disturbed areas displayed an overall stronger selection for conifer forests. These individuals further adjusted their selection for conifer forests in areas of their home‐ranges that were largely comprised of recent cutovers. This concurrent response to local and global anthropogenic disturbances provides evidence of nested‐hierarchical functional responses.

4. Synthesis and applications. Reliable characterization of disturbance effects on animals is necessary for conservation planning. Multi‐level functional responses can accurately describe animal distribution, and we provided a framework for modelling these responses. Our multi‐level functional responses indicate that fixing habitat requirements based on patterns of habitat selection for the average amount of disturbance can be misleading because it overlooks plasticity in the response of animals to habitat heterogeneity. For example, selection of closed‐canopy conifer forests by caribou generally became stronger with increasing disturbance levels. Anthropogenic disturbance thus could not only lead to the functional loss of residual habitat, but it can also increase the ‘relative value’ of residual patches. Our study provides a tool for more thorough assessments of spatial variation in the attractiveness of resource patches and, presumably, in the fitness benefits.
Cost–benefit analysis of ecological networks assessed through spatial analysis of ecosystem services
Authors: Newton Adrian C. , Hodder Kathy , Cantarello Elena , Perrella Lorretta , Birch Jennifer C. , Robins James , Douglas Sarah , Moody Christopher , Cordingley Justine
Published: October 2012

1. The development of ecological networks could enhance the ability of species to disperse across fragmented landscapes and could mitigate against the negative impacts of climate change. The development of such networks will require widespread ecological restoration at the landscape scale, which is likely to be costly. However, little information is available regarding the cost‐effectiveness of restoration approaches.

2. We address this knowledge gap by examining the potential impact of landscape‐scale habitat restoration on the value of multiple ecosystem services across the catchment of the River Frome in Dorset, England. This was achieved by mapping the market value of four ecosystem services (carbon storage, crops, livestock and timber) under three different restoration scenarios, estimating restoration costs, and calculating net benefits.

3. The non‐market value of additional services (cultural, aesthetic and recreational value) was elicited from local stakeholders using an online survey tool. Flood risk was assessed using a scoring approach. Spatial Multi‐Criteria Analysis (MCA) was conducted, incorporating both market and non‐market values, to evaluate the relative benefits of restoration scenarios. These were compared with impacts of restoration on biodiversity value.

4. Multi‐Criteria Analysis results consistently ranked restoration scenarios above a non‐restoration comparator, reflecting the increased provision of multiple ecosystem services. Restoration scenarios also provided benefits to biodiversity, in terms of increased species richness and habitat connectivity. However, restoration costs consistently exceeded the market value of ecosystem services.

5. Synthesis and applications. Establishment of ecological networks through ecological restoration is unlikely to deliver net economic benefits in landscapes dominated by agricultural land use. This reflects the high costs of ecological restoration in such landscapes. The cost‐effectiveness of ecological networks will depend on how the benefits provided to people are valued, and on how the value of non‐market benefits are weighted against the costs of reduced agricultural and timber production. Future plans for ecological restoration should incorporate local stakeholder values, to ensure that benefits to people are maximised.